281 results on '"Ki-Han Kim"'
Search Results
2. Comparison of Neural Activation Area in Primary Somatosensory Cortex and Brodmann Area 3 According to Finger and Phalange High-Frequency Vibration Stimulation
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Hyung-Sik Kim, Ji-Hun Jo, Je-Hyeop Lee, Jin-Ju Jung, Ki-Han Kim, Jin-Su An, Ye-Jin Kim, Mi-Hyun Choi, and Soon-Cheol Chung
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high-frequency vibrotactile stimulation ,finger and phalange ,neuronal activation ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
In this study, we measured neuronal activation in the primary somatosensory area (S1) and Brodmann area 3 (BA3) using 3T functional magnetic resonance imaging (fMRI) while presenting a 250-Hz high-frequency vibrational stimulus to each of three phalanges (distal, intermediate, and proximal) of four fingers of the right hand (index, middle, ring, and little). We compared the nerve activation area between each finger and each phalange. Ten healthy male college students (26.6 ± 2.5 years old) participated in this study. One session consisted of three blocks: a rest (30 s), stimulation (30 s), and response phase (9 s). In the rest phase, the vibrational stimulus was not presented. In the stimulation phase, the vibrational stimulation was presented at any one of the three phalanges of the selected finger. In the response phase, subjects were instructed to press a button corresponding to the phalange that they thought had received the vibration. The subtraction method was used to extract the activation area. The activation area in the S1 was the largest when the little finger was stimulated (for the finger comparison), and largest when the second phalange was stimulated (for the phalange comparison). The BA3 showed similar trends, and there was no statistically significant difference.
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- 2020
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3. Sequences of acetyl CoA carboxylase promoter for tumour necrosis factor action
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Keerang Park, Michael E. Pape, and Ki-Han Kim
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Pathology ,RB1-214 - Abstract
Tumour necrosis factor (TNF) inhibits the accumulation of acetyl CoA carboxylase (ACC) mRNA by decreasing the rate of ACC gene transcription. The ACC mRNA species found in 30A5 cells are generated from promoter II and TNF inhibits the accumulation of class 2 type mRNAs. By using 5' deletion mutants of promoter II fused to the bacterial chloramphenicol acetyltransferase (CAT) gene, the DNA mobility shift assay and the DNase I footprinting assay, the authors have identified the 30 bp from −389 to −359 as the TNF responsive element in promoter II. TNF treatment causes a decrease in the binding activity of nuclear protein(s) specific to the TNF responsive element. When the fragment containing the TNF responsive element was incorporated into the thymidine kinase promoter, the chimeric gene exhibited TNF induced inhibition of expression.
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- 1993
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4. Amorphous ITZO-Based Selector Device for Memristor Crossbar Array
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Ki Han Kim, Min-Jae Seo, and Byung Chul Jang
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memristor crossbar array ,amorphous In-Sn-Zn-O (a-ITZO) ,selector device ,Mechanical engineering and machinery ,TJ1-1570 - Abstract
In the era of digital transformation, a memristor and memristive circuit can provide an advanced computer architecture that efficiently processes a vast quantity of data. With the unique characteristic of memristor, a memristive crossbar array has been utilized for realization of nonvolatile memory, logic-in-memory circuit, and neuromorphic system. However, the crossbar array architecture suffers from leakage of current, known as the sneak current, which causes a cross-talk interference problem between adjacent memristor devices, leading to an unavoidable operational error and high power consumption. Here, we present an amorphous In-Sn-Zn-O (a-ITZO) oxide semiconductor-based selector device to address the sneak current issue. The a-ITZO-selector device is realized with the back-to-back Schottky diode with nonlinear current-voltage (I-V) characteristics. Its nonlinearity is dependent on the oxygen plasma treatment process which can suppress the surface electron accumulation layer arising on the a-ITZO surface. The a-ITZO-selector device shows reliable characteristics against electrical stress and high temperature. In addition, the selector device allows for a stable read margin over 1 Mbit of memristor crossbar array. The findings may offer a feasible solution for the development of a high-density memristor crossbar array.
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- 2023
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5. Tissue Ablation Using Irreversible Electrolytic Electroporation with Reduced Voltage
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Kim, Ki-Han Kim, Jinsu An, Young-Jin Park, Jung-Hoon Park, Hong Bae Kim, Jeong-Han Yi, and Hyung-Sik
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thermal tissue ablation ,electrical energy-inducing irreversible electroporation ,electrolysis ,ablation area ,synergistic effect - Abstract
Thermal tissue ablation may damage surrounding healthy tissue and cause pain. In this study, tissue ablation with the sequential application of electrical energy-inducing irreversible electroporation (IRE) and electrolysis (EL) (IRE + EL = IREEL) was investigated. An IREEL device was designed to control five output pulse parameters: voltage level (VL), pulse width (PW), pulse interval (PI), pulse number (PN), and pulse tail time (PTT). IREEL experiments were conducted on vegetable tissue. The results indicated that by increasing the VL and PTT, the ablation area increased, whereas the impedance was reduced significantly. Almost no ablation area was observed when only EL or IRE at 500 V and 1000 V, respectively, were applied. The ablation area observed with IRE alone at 1500 V was defined as 100%. In the case of IREEL at 500 V and 1000 V, ablation was induced even with the use of micro-second level PTT, and ablation areas of 91% and 186% were achieved, respectively. For IREEL at a voltage of 1500 V, the ablation area expanded to 209% and the maximum temperature was 48.7 °C, whereas the temperature did not exceed 30 °C under other conditions. A change in pH was also observed in an agar-gel phantom experiment which was conducted to examine and confirm whether IREEL induced electrolysis. IREEL was able induce ablation at low voltages owing to the synergistic effect of applying IRE and EL sequentially. Moreover, the ablation areas at high voltages could be increased compared to the areas observed when IRE and EL were applied independently.
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- 2023
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6. Multicenter Phase 2 Study about the Safety of No Antimicrobial Prophylaxis Use in Low-Risk Patients Undergoing Laparoscopic Distal Gastrectomy for Gastric Carcinoma (KSWEET-01 Study)
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Oh Jeong, Mi Ran Jung, Seong Yeob Ryu, Young-Kyu Park, Min Chan Kim, Ki Han Kim, Seung Wan Ryu, In Gyu Kwon, and Young Gil Son
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Diseases of the digestive system. Gastroenterology ,RC799-869 - Abstract
Background. Recent studies have shown a lower risk of surgical site infections (SSI) after laparoscopic distal gastrectomy compared to open surgery. This is a phase 2 study aiming to determine the incidence of SSI after laparoscopic distal gastrectomy without using antimicrobial prophylaxis (AMP). Methods. cT1N0 gastric cancers that were subject to laparoscopic distal gastrectomy were enrolled. Based on the unacceptable SSI incidence of ≥12.5% and the target SSI incidence of ≤5%, 105 patients were enrolled with an α of 0.05 and a power of 80% (ClinicalTrials.gov, NCT02200315). Results. In intention-to-treat analysis, patients did not reach the target SSI rate (12.4%, 95% confidence interval=6.8%–19.8%). Of patients, 44 patients had a protocol violation, such as extended lymph node dissection (LND) or inappropriate nonpharmacological SSI prevention measures. Per-protocol analysis excluding these patients (n=61) showed a SSI rate of 4.9%, which was within the target SSI range. Multivariate analysis revealed that extracorporeal anastomosis and extended LND were independent risk factors for SSI. Conclusions. This study failed to reach the target SSI rate without using AMP. However, per-protocol analysis suggests that no AMP might be feasible when limited LND and adequate SSI prevention measures were performed.
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- 2017
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7. An 8.5-Gb/s/Pin 12-Gb LPDDR5 SDRAM With a Hybrid-Bank Architecture, Low Power, and Speed-Boosting Techniques
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Jeong-Don Ihm, Byongwook Na, Hye-In Choi, Kim Sang-Yun, Seung-Jun Bae, Jae-Hoon Jung, Jin-Seok Heo, Seung-Jun Lee, Dae Hyun Kim, Junghwan Park, Won-Il Bae, Ki-Han Kim, Seouk-Kyu Choi, Jin-Hun Jang, Hangi-Jung, Duk-ha Park, Jung-Bae Lee, Seungki Hong, Young-Il Lim, Isak Hwang, Dong-Hun Lee, Kyungryun Kim, Nam Sung Kim, Dae-Hyun Kwon, Chang-Kyo Lee, Dongkeon Lee, Hyung-Joon Chi, and Geun-Tae Park
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Synchronization (alternating current) ,Interleaving ,Computer science ,Duty cycle ,Control theory ,Skew ,Electrical and Electronic Engineering ,Dram ,Electronic circuit ,Voltage ,Power (physics) - Abstract
An 8.5-Gb/s/pin (Gb/s) 12-Gb LPDDR5 SDRAM is implemented in a second-generation 10-nm DRAM process with a hybrid-bank architecture that provides a power-optimized bank solution depending on the bank modes (4B/4BG, 16B-merged bank, 8B-split bank). Based on the specified bank modes, vertical and horizontal skew-cancel schemes for high density and an RBUS-based DBI ac to minimize data transition are newly proposed. Thus, the switching power of RBUS DBI ac is saved by 8.9% compared to that of DBI ac “OFF.” To improve the rank interleaving efficiency with a current increase, partially enabled WCK (PE-WCK) mode is proposed, which minimizes the number of enabled circuits for maintaining the WCK2CK synchronization. Therefore, the current can be saved by 62% without a timing constraint compared to the WCK always-ON mode. To achieve high-speed operation beyond 6.4 Gb/s, speed-boosting techniques, namely, the two-step duty corrector, active resonant load (ARL), and one-tap decision feedback equalizer (DFE) with offset calibration, are newly adopted. In the coarse step in the two-step duty corrector, the value of the duty error decreases to below 5% by suppressing the dc signal. In the fine step, the remaining duty error is further reduced within 2.5 ps by the duty cycle monitor (DCM) and duty cycle adjustor (DCA). Moreover, the skew increase beyond 6.4 Gb/s due to the bandwidth limit by the heavy loading of four-phase WCK signals is alleviated by the ARL, where the four-phase skew is within 5 ps irrespective of process, voltage, and temperature (PVT) variations. The direct feedback DFE enables fast feedback (< 118 ps) for tap coefficient control, and offset calibration reduces the three-sigma offset of the four dynamic latches in DQ within 5 mV.
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- 2021
8. A 1.6V 1.4Gb/s/pin consumer DRAM with self-dynamic voltage-scaling technique in 44nm CMOS technology.
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Hyun-Woo Lee, Ki-Han Kim, Young-Kyoung Choi, Ju-Hwan Shon, Nak-Kyu Park, Kwan-Weon Kim, Chulwoo Kim, Young-Jung Choi, and Byong-Tae Chung
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- 2011
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9. Early experience of laparoscopic resection and comparison with open surgery for gastric gastrointestinal stromal tumor: a multicenter retrospective study
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Shin-Hoo Park, Hyuk-Joon Lee, Min-Chan Kim, Jeong-Hwan Yook, Tae-Sung Sohn, Woo-Jin Hyung, Seung-Wan Ryu, Yukinori Kurokawa, Young-Woo Kim, Sang-Uk Han, Hyung-Ho Kim, Do-Joong Park, Wook Kim, Sang-Il Lee, Haruhiko Cho, Gyu-Seok Cho, Jin-Jo Kim, Ki-Han Kim, Moon-Won Yoo, and Han-Kwang Yang
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Male ,Multidisciplinary ,Gastrointestinal Stromal Tumors ,Science ,Length of Stay ,Middle Aged ,Postoperative Complications ,Treatment Outcome ,Risk Factors ,Stomach Neoplasms ,Medicine ,Humans ,Multicenter Studies as Topic ,Female ,Laparoscopy ,Neoplasm Recurrence, Local ,Digestive System Surgical Procedures ,Aged ,Proportional Hazards Models ,Retrospective Studies - Abstract
The advantages of laparoscopic resection over open surgery in the treatment of gastric gastrointestinal stromal tumor (GIST) are not conclusive. This study aimed to evaluate the postoperative and oncologic outcome of laparoscopic resection for gastric GIST, compared to open surgery. We retrospectively reviewed the prospectively collected database of 1019 patients with gastric GIST after surgical resection at 13 Korean and 2 Japanese institutions. The surgical and oncologic outcomes were compared between laparoscopic and open group, through 1:1 propensity score matching (PSM). The laparoscopic group (N = 318) had a lower rate of overall complications (3.5% vs. 7.9%, P = 0.024) and wound complications (0.6% vs. 3.1%, P = 0.037), shorter hospitalization days (6.68 ± 4.99 vs. 8.79 ± 6.50, P
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- 2021
10. A 1.6V 3.3Gb/s GDDR3 DRAM with dual-mode phase- and delay-locked loop using power-noise management with unregulated power supply in 54nm CMOS.
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Hyun-Woo Lee, Won-Joo Yun, Young-Kyoung Choi, Hyang-Hwa Choi, Jong-Jin Lee, Ki-Han Kim, Shin-Deok Kang, Ji-Yeon Yang, Jae-Suck Kang, Hyeng-Ouk Lee, Dong-Uk Lee, Sujeong Sim, Young-Ju Kim 0001, Won-Jun Choi, Keun-Soo Song, Sang-Hoon Shin, Hyung-Wook Moon, Seung-Wook Kwack, Jung-Woo Lee, Nak-Kyu Park, Kwan-Weon Kim, Young-Jung Choi, Jin-Hong Ahn, and Byong-Tae Chung
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- 2009
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11. A simple method for removing initial irregularity of an electrocardiogram during a transient state of a power supply in a defibrillator
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Jeong-Han Yi, Jin-Su Ahn, Ki-Han Kim, and Hyung Sik Kim
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Transient state ,Computer science ,0206 medical engineering ,Biomedical Engineering ,Biophysics ,Health Informatics ,Bioengineering ,02 engineering and technology ,electrocardiogram ,Electric Capacitance ,Electromagnetic interference ,law.invention ,galvanic isolation ,Biomaterials ,03 medical and health sciences ,Electrocardiography ,Defibrillator ,0302 clinical medicine ,Electric Power Supplies ,law ,Humans ,Computer Simulation ,Biosignal ,irregularity ,transient state ,business.industry ,Electrical engineering ,Equipment Design ,020601 biomedical engineering ,Power (physics) ,Capacitor ,Transient (oscillation) ,Ground noise ,business ,Galvanic isolation ,Electromagnetic Phenomena ,030217 neurology & neurosurgery ,Information Systems ,Defibrillators ,Research Article - Abstract
BACKGROUND: The defibrillator is a device that instantaneously discharges the high energy stored in the capacitor to the human body to help revitalize the heart. The circuit for charging the capacitor uses the same power source as the biosignal measurement unit. Therefore, variation in main power supply voltage, ground noise, and electromagnetic interference from the charging circuit can induce distortion into the biosignal at the initial stage of charging. OBJECTIVE: In this study, a simple method is proposed for removing the initial irregularity of an electrocardiogram due to the transient state of a power supply. METHODS: To evaluate the method, a 1-channel electrocardiogram measurement unit and peripheral units were separated from the main control module using galvanic isolation. An isolated push-pull converter was designed to power the secondary side. The method was tested under steady-state and transient conditions. RESULTS: The obtained results proved that biosignal distortion can be significantly reduced. CONCLUSION: This method could be another simple implementation approach for solving signal distortions due to the transient status of power supplies used in medical devices.
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- 2020
12. A simple segmentation and quantification method for numerical quantitative analysis of cells and tissues
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Ki-Han Kim, Hong-Bae Kim, Hyun-Kyu Kang, Jin-Su Ahn, Hyung-Sik Kim, and Jeong-Han Yi
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Microscope ,Computer science ,Swine ,Cells ,0206 medical engineering ,microscope image ,Biomedical Engineering ,Biophysics ,image process ,Color ,Health Informatics ,Bioengineering ,Image processing ,02 engineering and technology ,Grayscale ,law.invention ,Pattern Recognition, Automated ,Biomaterials ,03 medical and health sciences ,0302 clinical medicine ,Segmentation ,law ,Image Processing, Computer-Assisted ,Animals ,Decellularization ,business.industry ,Binary image ,Numerical analysis ,Pattern recognition ,020601 biomedical engineering ,Aortic Valve ,Outlier ,decellularization ,Artificial intelligence ,business ,030217 neurology & neurosurgery ,Algorithms ,Information Systems ,Research Article - Abstract
Background Microscopic image analysis based on image processing is required for quantitative evaluation of decellularization. Existing methods are not widely used because of expensive commercial software, and machine learning-based techniques lack generality for decellularization because many high-resolution image data has to be processed. Objective In this study, we developed an image processing algorithm for quantitative analysis of tissues and cells in a general microscopic image. Methods The proposed method extracts the color images obtained by the microscope into reference images consisting of grayscale, red (R), green (G), and blue (B) information and transforms each into a binary image. The transformed images were extracted by separating the cells and tissues through outlier noise elimination, logical multiplication and labeling. In order to verify the method, decellularization of porcine arotic valve was performed by the electrical method. Slice samples were obtained by time and the proposed method was applied. Results The experimental results show that the segmentation of cells and tissues, and quantitative analysis of the number of cells and changes in tissue area during the decellularization process was possible. Conclusions The proposed method shows that cell and tissue extraction and quantitative numerical analysis were possible in different brightness of microscopic images.
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- 2020
13. 22.2 An 8.5Gb/s/pin 12Gb-LPDDR5 SDRAM with a Hybrid-Bank Architecture using Skew-Tolerant, Low-Power and Speed-Boosting Techniques in a 2nd generation 10nm DRAM Process
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Kim Sang-Yun, Junghwan Park, Soo-bong Chang, Won-Il Bae, Ki-Won Park, Hyuck-Joon Kwon, Seung-Jun Bae, Geun-Tae Park, Hyung-Joon Chi, Kyung-Ho Lee, Hye-In Choi, Ji-Suk Kwon, Gil-Young Kang, Seung-Jun Lee, Hyunyoon Cho, Jin-Seok Heo, Young-Soo Sohn, Lim Suk-Hyun, Kyung Ryun Kim, Kwang-Il Park, Daesik Moon, Chang-Kyo Lee, Jae-Hoon Jung, Dongkeon Lee, Chang-Ho Shin, Cheol Kim, Jung-Bae Lee, Young-Il Lim, Dae Hyun Kim, Jinsol Park, Seouk-Kyu Choi, Jin-Hun Jang, Ki-Han Kim, Young Hoon Son, Byongwook Na, Isak Hwang, Duk-ha Park, Su-Yeon Doo, and Choi Yeon-Kyu
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Boosting (machine learning) ,business.industry ,Computer science ,law ,Transistor ,Skew ,Process (computing) ,business ,Computer hardware ,Dram ,Power (physics) ,Jitter ,law.invention - Abstract
Energy efficiency in mobile devices is a pivotal criteria from the overall system point of view, Although the 7,5Gb/s 8Gb LPDDR5 [1], with low-power schemes (internal data copy, dynamic-voltage-frequency scaling (DVFS), and a deep-sleep mode (DSM)), achieves improved energy efficiency compared to the previous LPDDR4X [2], the market demands for higher density and speed gradually increase for high-end applications including hand-held artificial intelligence (AI) and advanced driver assistance system (ADAS), To achieve higher density and speed in a power-efficient manner, this paper proposes a 8,5Gb/s 12Gb LPDDR5 with a hybrid bank architecture (split/merged bank), a skew-tolerant scheme, bus-based ROBI AC, and speed-boosting techniques based on 2nd generation 10nm DRAM process, Adopting a hybrid bank architecture and skew-tolerant scheme enables high speed and power-optimization for each bank-mode in high density memories, Moreover, bus-based RDBI AC achieves 2,1 % current gain and command-based WCK control scheme achieves 36mA saving at WCK-always-on mode, The speed-boosting techniques (duty-cycle correction (DCC), an active-resonant load, and at-tap DFE receiver) provide improved operating speeds from 7,5Gb/s to 8,5Gb/s@VDD2H = 1, 05V, where the read/write DQ valid windows are 0,60UI and 0.64UI (1UI = 118ps).
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- 2020
14. A 5Gb/s/pin 16Gb LPDDR4/4X Reconfigurable SDRAM with Voltage-High Keeper and a Prediction-based Fast-tracking ZQ Calibration
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Daesik Moon, Jung-Hwan Choi, Seok-Hun Hyun, Jung-Bae Lee, Sung-Woo Yoon, Su-Jin Park, Dong-Hoon Lee, Jin-Hyeok Baek, Seung-Jun Bae, Y.S. Park, Hui-Kap Yang, Ki-Han Kim, Hyuck-Joon Kwon, Young-Soo Sohn, Chang-Kyo Lee, Bok-Gue Park, Young-Jae Kim, Jin-Seok Heo, Kyungryun Kim, Soobong Jang, Ki-Ho Kim, Joung-Wook Moon, Kwang-Il Park, and Jae-Hyung Lee
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Computer science ,PHY ,business.industry ,Voltage control ,Detector ,business ,Dram ,Computer hardware ,Fast tracking ,Voltage - Abstract
A 5Gb/s/pin 16Gb LPDDR4/4X reconfigurable SDRAM with a self-mode detection scheme, a voltage-high keeper (VHK) for un-terminated load and a prediction-based fast-tracking ZQ algorithm is implemented in 10nm class ($2^{nd}$ generation) DRAM process. Providing a reconfigurable LVSTL with a mode detection scheme to support two different DRAM interface standards (LPDDR4/4X) depending on I/O supply voltage $(V_{DDQ})$, a proposed design can maintain the system compatibility and longevity to the legacy controller and the PHY structure. The VHK for LPDDR4 enables the 3.2Gb/s operation in the un-terminated load similar to LPDDR4X by alleviating the inter symbol interference (ISI) through the controlled leakage current. In a ZQ calibration, the proposed ZQ algorithm achieves fast ZQ code searching, the calibration time can be reduced by 30% in PVT variation. Moreover, an internal ZQ calibration (IZQC) is newly adopted to minimize the variation of the driver strength to PVT variation.
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- 2019
15. Enhancing light-extraction efficiency of OLEDs with high- and low-refractive-index organic–inorganic hybrid materials
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Ki-Han Kim and Soo-Young Park
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Materials science ,02 engineering and technology ,010402 general chemistry ,Methacrylate ,01 natural sciences ,Biomaterials ,chemistry.chemical_compound ,Materials Chemistry ,OLED ,Copolymer ,Organic chemistry ,Electrical and Electronic Engineering ,Methyl methacrylate ,Sol-gel ,chemistry.chemical_classification ,General Chemistry ,Polymer ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,Tetraethyl orthosilicate ,chemistry ,Chemical engineering ,0210 nano-technology ,Hybrid material - Abstract
High- and low-refractive-index hybrid materials were prepared by an in situ acid-free sol–gel process for internal and external light-extraction layers in organic light-emitting diodes (OLEDs). A random copolymer of methyl methacrylate (MMA) and 3-(trimethoxysilyl) propyl methacrylate (MSMA), poly(MMA-co-MSMA), which was capped with trialkoxysilane in MSMA units, was used as a precursor. The precursor was further reacted with titanium(IV) isopropoxide (TTIP) and tetraethyl orthosilicate (TEOS) to synthesize the high- and low-refractive-index hybrid materials, respectively, in which TiO2 and SiO2 nanoparticles were well dispersed, respectively, in the polymer matrix. After the reactions with TTIP and TEOS, the refractive index increased to 1.81 and decreased to 1.44 from 1.50 of the precursor, respectively. The luminance, power, and current efficiency of the OLED with an external light-extraction layer were enhanced by 21.3, 28.6, and 29.1%, respectively, those of the OLED with an internal light-extraction layer were increased by 62.4, 76.9, and 59.2%, respectively, and those of the device with combined ELEL and ILEL were enhanced by 62.7, 77.2, and 59.3%, respectively, when compared to values for the reference OLED without an internal or external light-extraction layer. These results indicate that high- and low-refractive-index materials are desirable for enhancement in light-extraction efficiency, and they can provide practical solutions for various applications such as OLED displays and lighting.
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- 2016
16. Afferent Loop Syndrome After Subtotal Gastrectomy With Billroth-II Reconstruction: Etiology and Treatment
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Jong-Young Oh, Ki-Han Kim, Min Chan Kim, and Sung-Heun Kim
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Billroth II ,medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,030218 nuclear medicine & medical imaging ,Surgery ,03 medical and health sciences ,0302 clinical medicine ,030220 oncology & carcinogenesis ,medicine ,Etiology ,Subtotal gastrectomy ,Gastrectomy ,business ,Afferent loop syndrome - Abstract
The aim of this study was to evaluate the clinical characteristics, treatment, and prognosis of afferent loop syndrome (ALS) following radical subtotal gastrectomy with B-II reconstruction in gastric cancer patients. ALS is an infrequent mechanical complication, which occurs after reconstruction of Billroth-II (B-II) gastrojejunostomy or Roux-en-Y esophagojejunosotomy. From 2002 through 2010, 672 patients who had undergone subtotal gastrectomy with B-II reconstruction for gastric cancer were enrolled. Clinical data, symptom interval, cause, and treatment of 13 ALS patients were reviewed. The body mass index (BMI) of patients who suffered ALS was significantly less than that of patients who did not (P = 0.0244). And, there were significant differences in rates of recurrence (P = 0.0032) and follow-up duration (P = 0.0119) between the two groups. Acute ALS within 1 month occurred in 5 patients (38.5%). Obstructive jaundice or acute pancreatitis occurred in 4 patients (30.1%). The most frequent cause was anastomosis inflammation (6 patients). Only 2 patients required surgery. Most patients with ALS were treated conservatively with or without percutaneous transhepatic biliary drainage (PTBD). Clinical suspicion is of significant importance because ALS is not common and the symptoms are nonspecific. ALS occurs more frequently in low BMI patients than high. PTBD can be considered as a primary treatment option for ALS if rupture of the afferent loop is not present.
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- 2016
17. Role of Percutaneous Transhepatic Biliary Drainage in Patients With Complications After Gastrectomy
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Min Chan Kim, Ho Byoung Lee, Ghap Joong Jung, Sung Heun Kim, and Ki Han Kim
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medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Malignancy ,medicine.disease ,Surgery ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Duodenum ,Medicine ,030211 gastroenterology & hepatology ,Gastrectomy ,In patient ,Percutaneous transhepatic biliary drainage ,Radiologic Procedure ,business ,Afferent loop syndrome ,Proximal duodenum - Abstract
The aim of this study was to elucidate the role of percutaneous transhepatic biliary drainage (PTBD) in patients with duodenal stump leakage (DSL) and afference loop syndrome (ALS) postgastrectomy for malignancy or benign ulcer perforation. Percutaneous transhepatic biliary drainage (PTBD) is an interventional radiologic procedure used to promote bile drainage. Duodenal stump leakage (DSL) and afferent loop syndrome (ALS) can be serious complications after gastrectomy. From January 2002 through December 2014, we retrospectively reviewed 19 patients who underwent PTBD secondary to DSL and ALS postgastrectomy. In this study, a PTBD tube was placed in the proximal duodenum near the stump or distal duodenum in order to decompress and drain bile and pancreatic fluids. Nine patients with DSL and 10 patients with ALS underwent PTBD. The mean hospital stay was 34.3 days (range, 12 to 71) in DSL group and 16.4 days (range, 6 to 48) in ALS group after PTBD. A liquid or soft diet was started within 2.6 days (range, 1 to 7) in the ALS group and within 3.4 days (range, 0 to 15) in the DSL group after PTBD. One patient with DSL had PTBD changed, and 2 patients with ALS underwent additional surgical interventions after PTBD. The PTBD procedure, during which the tube was inserted into the duodenum, was well-suited for decompression of the duodenum as well as for drainage of bile and pancreatic fluids. This procedure can be an alternative treatment for cases of DSL and ALS postgastrectomy.
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- 2016
18. Comparison of Neural Activation Area in Primary Somatosensory Cortex and Brodmann Area 3 According to Finger and Phalange High-Frequency Vibration Stimulation
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Je-Hyeop Lee, Ji-Hun Jo, Jin-Ju Jung, Ki-Han Kim, Mi-Hyun Choi, Ye-Jin Kim, Jin-Su An, Soon-Cheol Chung, and Hyung Sik Kim
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high-frequency vibrotactile stimulation ,Stimulation ,Stimulus (physiology) ,Somatosensory system ,lcsh:Technology ,050105 experimental psychology ,lcsh:Chemistry ,03 medical and health sciences ,0302 clinical medicine ,medicine ,0501 psychology and cognitive sciences ,General Materials Science ,lcsh:QH301-705.5 ,Instrumentation ,Fluid Flow and Transfer Processes ,medicine.diagnostic_test ,lcsh:T ,business.industry ,Process Chemistry and Technology ,05 social sciences ,General Engineering ,Anatomy ,Little finger ,Phalanx ,neuronal activation ,Neuronal activation ,lcsh:QC1-999 ,Computer Science Applications ,medicine.anatomical_structure ,lcsh:Biology (General) ,lcsh:QD1-999 ,lcsh:TA1-2040 ,finger and phalange ,lcsh:Engineering (General). Civil engineering (General) ,Functional magnetic resonance imaging ,business ,lcsh:Physics ,030217 neurology & neurosurgery ,Brodmann area - Abstract
In this study, we measured neuronal activation in the primary somatosensory area (S1) and Brodmann area 3 (BA3) using 3T functional magnetic resonance imaging (fMRI) while presenting a 250-Hz high-frequency vibrational stimulus to each of three phalanges (distal, intermediate, and proximal) of four fingers of the right hand (index, middle, ring, and little). We compared the nerve activation area between each finger and each phalange. Ten healthy male college students (26.6 ±, 2.5 years old) participated in this study. One session consisted of three blocks: a rest (30 s), stimulation (30 s), and response phase (9 s). In the rest phase, the vibrational stimulus was not presented. In the stimulation phase, the vibrational stimulation was presented at any one of the three phalanges of the selected finger. In the response phase, subjects were instructed to press a button corresponding to the phalange that they thought had received the vibration. The subtraction method was used to extract the activation area. The activation area in the S1 was the largest when the little finger was stimulated (for the finger comparison), and largest when the second phalange was stimulated (for the phalange comparison). The BA3 showed similar trends, and there was no statistically significant difference.
- Published
- 2020
19. Multicenter Phase 2 Study about the Safety of No Antimicrobial Prophylaxis Use in Low-Risk Patients Undergoing Laparoscopic Distal Gastrectomy for Gastric Carcinoma (KSWEET-01 Study)
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Seung Wan Ryu, Young-Kyu Park, Ki Han Kim, Young Gil Son, Oh Jeong, Seong Yeob Ryu, In Gyu Kwon, Mi Ran Jung, and Min Chan Kim
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medicine.medical_specialty ,Multivariate analysis ,Hepatology ,Article Subject ,business.industry ,Incidence (epidemiology) ,Gastroenterology ,Phases of clinical research ,Anastomosis ,Lower risk ,Extracorporeal ,Surgery ,03 medical and health sciences ,Dissection ,0302 clinical medicine ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,medicine ,Clinical Study ,lcsh:Diseases of the digestive system. Gastroenterology ,030212 general & internal medicine ,lcsh:RC799-869 ,business ,Lymph node - Abstract
Background. Recent studies have shown a lower risk of surgical site infections (SSI) after laparoscopic distal gastrectomy compared to open surgery. This is a phase 2 study aiming to determine the incidence of SSI after laparoscopic distal gastrectomy without using antimicrobial prophylaxis (AMP). Methods. cT1N0 gastric cancers that were subject to laparoscopic distal gastrectomy were enrolled. Based on the unacceptable SSI incidence of ≥12.5% and the target SSI incidence of ≤5%, 105 patients were enrolled with an α of 0.05 and a power of 80% (ClinicalTrials.gov, NCT02200315). Results. In intention-to-treat analysis, patients did not reach the target SSI rate (12.4%, 95% confidence interval=6.8%–19.8%). Of patients, 44 patients had a protocol violation, such as extended lymph node dissection (LND) or inappropriate nonpharmacological SSI prevention measures. Per-protocol analysis excluding these patients (n=61) showed a SSI rate of 4.9%, which was within the target SSI range. Multivariate analysis revealed that extracorporeal anastomosis and extended LND were independent risk factors for SSI. Conclusions. This study failed to reach the target SSI rate without using AMP. However, per-protocol analysis suggests that no AMP might be feasible when limited LND and adequate SSI prevention measures were performed.
- Published
- 2017
20. 23.2 A 5Gb/s/pin 8Gb LPDDR4X SDRAM with power-isolated LVSTL and split-die architecture with 2-die ZQ calibration scheme
- Author
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Hyo-Joo Ahn, Jae-Young Lee, Yoon-Joo Eom, Seok-Hun Hyun, Junha Lee, Kyoung-Ho Kim, Jong-Min Bang, Yong-Cheol Bae, Hye-Ran Kim, Hoon Lee, Jong-Hyuk Kim, Joon-Young Park, Seung-Jun Shin, Ki-Han Kim, Tae-Young Oh, Hanna Park, Hyuck-Joon Kwon, Young-Ryeol Choi, Yoon-Hwan Yoon, In-Dal Song, Youn-sik Park, Su-Jin Park, Soo-bong Chang, Kwang-Il Park, Kyong-Ho Jeon, Jin-Hee Park, Jung-Sik Kim, Chang-Kyo Lee, Young Sang Choi, Yoon-Gyu Song, Hyong-Ryol Hwang, Du-Yeul Kim, Gyo-Young Jin, Ho-Jun Chang, Seong-Jin Jang, Jung-Hwan Choi, and Seung-Jun Bae
- Subjects
Scheme (programming language) ,Engineering ,business.industry ,020208 electrical & electronic engineering ,Power efficient ,02 engineering and technology ,Die (integrated circuit) ,020202 computer hardware & architecture ,Power (physics) ,Embedded system ,0202 electrical engineering, electronic engineering, information engineering ,Calibration ,Architecture ,business ,computer ,Dram ,Wearable technology ,computer.programming_language - Abstract
With growing demand for low-power mobile applications, such as wearable devices, smart phones and tablet PCs, low-power mobile DRAM has been identified as a mandatory requirement for low-power system designs. The recently developed LPDDR4 [1] is still a power efficient solution because of its architectural approaches and low-voltage-swing terminated logic (LVSTL). However, demand for enhanced power-efficiency beyond LPDDR4 is still increasing for mobile applications. In this work, a 5.0Gbp/s/pin 8Gb LPDDR4X memory with power-isolated low-voltage-swing terminated logic (PI-LVSTL) and a split-die architecture is proposed to enhance power-efficiency and mass production yield.
- Published
- 2017
21. Readmissions following elective radical total gastrectomy for early gastric cancer: A case-controlled study
- Author
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Ki-Han Kim, Min Chan Kim, Yoo-Min Kim, Yong-Deok Kim, and Ghap-Joong Jung
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Male ,Reoperation ,medicine.medical_specialty ,medicine.medical_treatment ,Patient Readmission ,Quality of life ,Clinicopathologic feature ,Gastrectomy ,Stomach Neoplasms ,medicine ,Humans ,Aged ,Retrospective Studies ,Hospital stay ,business.industry ,General surgery ,Incidence (epidemiology) ,Case-control study ,General Medicine ,Middle Aged ,After discharge ,Readmission rate ,Early Gastric Cancer ,Surgery ,Total gastrectomy ,Case-Control Studies ,Female ,Gastric cancer ,business ,Readmission - Abstract
Background Readmission after gastrectomy is one of the factors that reflect quality of life. Therefore, we analyzed the several factors related to readmissions after total gastrectomy for early gastric cancer. Methods From January 2002 through December 2009, 102 consecutive patients who underwent radical total gastrectomy for early gastric cancer were enrolled in this study. We evaluated the incidence, cause, time point, and type of treatment for readmission after discharge; we compared the readmission and non-readmission groups in regard to clinicopathologic features and postoperative outcomes. Results The readmission rate during the five years after total gastrectomy was 22 of 102 (21.6%). The most common cause for readmission was esophagojejunostomy stricture (5 cases). The treatment given for 31 readmissions included 23 conservative therapies, 3 radiologic or endoscopic interventions, and 5 re-operations. No significant differences were detected in the clinicopathologic feature, postoperative outcomes, or 5-year survival rates between the readmission and non-readmission group. No specific risk factor was found to be associated with readmission. Conclusion Although we could not determine a specific risk factor associated with readmission after radical total gastrectomy, prevention of readmission by evaluating the causes and treatments after radical total gastrectomy can improve the patient's quality of life.
- Published
- 2014
22. Vertical Alignment Liquid Crystal Device With Reduced Off-Axis Gamma Shift
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Tae-Hoon Yoon, Sung-Tae Shin, Jung-Wook Kim, Ki-Han Kim, and Sun-Wook Choi
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Liquid crystal devices ,Materials science ,business.industry ,Manufacturing process ,Biasing ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,Threshold voltage ,Vertical alignment ,Liquid crystal ,Electrode ,Optoelectronics ,Electrical and Electronic Engineering ,business - Abstract
We propose a vertical alignment (VA) liquid crystal (LC) device with reduced off-axis gamma shift. We can form a multi-domain structure by simply designing the electrode structure . By applying a different bias voltage to each sub-pixel, we obtained a threshold voltage difference of 2.4 V, without any complex manufacturing process. We confirmed that the off-axis gamma shift can be significantly reduced by the proposed method. We believe that the proposed method can be easily applied to reduce the off-axis gamma shift in vertical alignment LC devices.
- Published
- 2013
23. P.103: High Transmittance LC Mode Based on Fringe Field Switching of Vertically-Aligned Negative LCs
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Dong Han Song, Jung-Wook Kim, Ki-Han Kim, and Tae-Hoon Yoon
- Subjects
Condensed Matter::Soft Condensed Matter ,Vertical alignment ,High transmittance ,Optics ,Materials science ,Field (physics) ,business.industry ,Liquid crystal ,Electric field ,Transmittance ,Mode (statistics) ,business - Abstract
In this work we propose a liquid crystal mode in which vertically-aligned negative nematic liquid crystals are switched on by applying a fringe electric field. In the proposed mode, vertically-aligned negative liquid crystals can be switched on by the vertical as well as in-plane components of an applied fringe field so that high transmittance can be achieved. By fabricating a test cell, we experimentally obtained a transmittance of 33.7 %, which is 8.7 % higher than a homogeneously-aligned fringe field switching cell using positive liquid crystals.
- Published
- 2013
24. Fast Fringe-field-switching Liquid Crystal Cell with a Protrusion Structure
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Sung Gu Kang, Jeong Hwan Yoon, Sung-il Park, Tae-Hoon Yoon, Ki-Han Kim, Yu Ri Shim, Byeong Koo Kim, Sun-Wook Choi, Sun Yong Lee, and Dong Han Song
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Liquid-crystal display ,Materials science ,Field (physics) ,business.industry ,fungi ,food and beverages ,Response time ,Atomic and Molecular Physics, and Optics ,law.invention ,Optics ,law ,Liquid crystal ,Electric field ,Electrode ,Transmittance ,Liquid crystal cell ,business - Abstract
We propose a cell structure for the fast switching of liquid crystals by the fringe field. By forming protrusion between patterned electrodes, we can obtain enhancement of response time. The protrusion reduces the effective cell gap, with which a fast response time can be realized. There is little decrease in the transmittance because the protrusion is located between patterned electrodes. We confirmed that the total response time can be decreased by 33% with little loss of the transmittance by optimizing the shape of the protrusion structure.
- Published
- 2013
25. Vertical alignment of liquid crystals without alignment layers
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Hoon Kim, Ki-Han Kim, Sun-Wook Choi, Tae-Hoon Yoon, Ki-Chul Shin, Byung Wok Park, Hee Seop Kim, and Ji-Hoon Lee
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Materials science ,Fabrication ,business.industry ,Mixing (process engineering) ,Nanotechnology ,General Chemistry ,engineering.material ,Condensed Matter Physics ,Manufacturing cost ,Display device ,Vertical alignment ,Coating ,Liquid crystal ,engineering ,Optoelectronics ,General Materials Science ,business ,Polyimide - Abstract
We propose a method for vertical alignment (VA) of liquid crystals (LCs) without alignment layers by mixing only a very low concentration (0.05 wt%) of an organic compound with LCs. The electro-optic characteristics of a VA cell fabricated by the proposed method were almost the same as those of a conventional VA cell with VA layers. Moreover, we used the proposed method to realise a polymer-stabilised VA device with a rapid response time without alignment layers. The proposed method can simplify the fabrication process and reduce the manufacturing cost of LC display devices by removing the need for alignment layers and the alignment process such as coating of polyimide layers and the UV exposure for the photo-alignment. We believe that the proposed method can play an essential role in the fabrication of plastic flexible LC display devices requiring the low-temperature process.
- Published
- 2013
26. Association between Phosphorylated AMP-Activated Protein Kinase and MAPK3/1 Expression and Prognosis for Patients with Gastric Cancer
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Ki Han Kim, Jong Gwang Kim, Min Chan Kim, Sung Yong Oh, Byung Woog Kang, You Jin Lee, Soo Jung Lee, Su-Jin Kim, and Yee Soo Chae
- Subjects
Adult ,Male ,Cancer Research ,medicine.medical_specialty ,Pathology ,Kaplan-Meier Estimate ,AMP-Activated Protein Kinases ,Adenocarcinoma ,Protein Serine-Threonine Kinases ,Gastroenterology ,Disease-Free Survival ,Young Adult ,Stomach Neoplasms ,Internal medicine ,medicine ,Humans ,Phosphorylation ,Protein kinase A ,PI3K/AKT/mTOR pathway ,Aged ,Proportional Hazards Models ,Aged, 80 and over ,Mitogen-Activated Protein Kinase 1 ,Mitogen-Activated Protein Kinase 3 ,Tissue microarray ,Proportional hazards model ,Kinase ,business.industry ,Hazard ratio ,Pyruvate Dehydrogenase Acetyl-Transferring Kinase ,Cancer ,General Medicine ,Middle Aged ,Prognosis ,medicine.disease ,Carcinoembryonic Antigen ,Oncology ,Multivariate Analysis ,Immunohistochemistry ,Female ,business ,Protein Processing, Post-Translational - Abstract
Objectives: Phosphorylated AMP-activated protein kinase (pAMPK) plays a central role in cellular metabolic sensing and energy balance homeostasis, and interacts with various pathways [e.g., TP53, mTOR, NUAK2 (sucrose nonfermenting-like kinase), MAPK3/1 (ERK) and PDK]. Therefore, the present study analyzed the expression of pAMPK, NUAK2, MAPK3/1 and PDK-1 and their effect on the survival of patients with resected gastric cancer. Methods: A total of 621 patients with gastric adenocarcinoma surgically resected with curative intent were enrolled in the study. Immunohistochemical staining for pAMPK, NUAK2, MAPK3/1 and PDK-1 was performed using tissue microarrays of surgical specimens of gastric cancer tissue. Results: Positive pAMPK, NUAK2, MAPK3/1 and PDK-1 expression was observed in 379 (61.0%), 257 (41.4%), 327 (52.7%) and 67 (10.8%) cases, respectively. Multivariate survival analysis showed a significantly better survival for the patients with positive pAMPK or MAPK3/1 expression than for the patients with a negative expression [pAMPK: disease-free survival (DFS), hazard ratio (HR) = 0.750, 95% confidence interval (CI) = 0.568-0.970, p = 0.030; MAPK3/1: DFS, HR = 0.692, 95% CI = 0.720-0.974, p = 0.021), while NUAK2 or PDK-1 expression had no effect on survival. Conclusion: pAMPK or MAPK3/1 expression was found to be an independent prognostic marker for patients with resected gastric cancer.
- Published
- 2013
27. High-transmittance in-plane switching liquid crystal display device driven by three-level voltages
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Dong Han Song, Tae-Hoon Yoon, and Ki-Han Kim
- Subjects
Liquid-crystal display ,Materials science ,Pixel ,business.industry ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,law.invention ,High transmittance ,Optics ,law ,Liquid crystal ,Electric field ,Electrode ,Transmittance ,Optoelectronics ,Electrical and Electronic Engineering ,business ,Voltage - Abstract
We propose a single-layered electrode structure using three voltage levels instead of two to achieve high transmittance in an in-plane switching liquid crystal display device. The proposed structure consists of two pixel electrodes and one common electrode. By using three voltage levels, we can generate an in-plane electric field higher than that in a conventional in-plane switching device. We confirmed that by using the proposed structure, the transmittance of a liquid crystal device can be increased from 29% to 35% at a slightly lower operating voltage without using the double-layered electrode structure required for the fringe-field switching mode. The transmittance of the proposed device is higher than that of the fringe-field switching device.
- Published
- 2013
28. Dark-state Color Shift and Gray Scale Inversion in an In-plane Switching Liquid Crystal Display Device
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Tae-Hoon Yoon, Sung-il Park, Jeong Hwan Yoon, Kyoung-Ho Park, Joun-Ho Lee, Byeong-Hun Yu, Ki-Han Kim, and Byeong Koo Kim
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Physics ,Liquid-crystal display ,Image quality ,business.industry ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Color shift ,Inversion (meteorology) ,Grayscale ,GeneralLiterature_MISCELLANEOUS ,Atomic and Molecular Physics, and Optics ,Computer Science::Other ,law.invention ,Dark state ,Optics ,law ,Liquid crystal ,Computer Science::Computer Vision and Pattern Recognition ,business ,ComputingMethodologies_COMPUTERGRAPHICS ,Poincare sphere - Abstract
Off-axis color shift in the dark state and gray scale inversion in an in-plane switching (IPS) liquid crystal display (LCD) device were investigated. Analyses were performed using the Poincare sphere representation. The results show that color shift in the dark state and gray scale inversion in an IPS LCD can be reduced by using a biaxial film. We confirmed the extent of these improvements by measuring the optical performance of a fabricated IPS LCD.
- Published
- 2012
29. Fascin expression is related to poor survival in gastric cancer
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Jin Seok Jang, Ki Han Kim, Hyuk Chan Kwon, Su-Jin Kim, Yu Mi Kim, Jin Sook Jeong, Ghap Joong Jung, Dae Cheol Kim, and Min Chan Kim
- Subjects
Pathology ,medicine.medical_specialty ,Tissue microarray ,biology ,business.industry ,Lymphovascular invasion ,Cancer ,macromolecular substances ,General Medicine ,medicine.disease ,Pathology and Forensic Medicine ,Metastasis ,Galectin-3 ,Cancer cell ,biology.protein ,Medicine ,Immunohistochemistry ,business ,Fascin - Abstract
Fascin is an actin-binding protein that provides mechanical support and cell motility, and involves cancer cell metastasis. We investigated fascin protein expression in gastric cancer and assessed their relationship with clinicopathologic parameters and survival rates. In addition, we researched galectin-3 protein expression to study fascin action mechanisms. We performed immunohistochemisty with fascin and galectin-3 antibodies in 471 gastric carcinomas, using tissue microarrays. Fascin was positive in 14.9% (70/471) of the samples, and fascin expression was related to worse survival rates (P < 0.001), high clinical stage (P < 0.001), high T stage (P < 0.001), nodal metastasis (P < 0.001), lymphovascular invasion (P= 0.001) and the intestinal type of Lauren classification (P= 0.015). Galectin-3 protein expression was positive in 83.9% (395/471) of the samples and was reversely correlated with fascin protein expression (P= 0.020). Galectin-3 expression was related to low clinical stage (P < 0.001), but not to survival rates in multivariate analysis. In multivariate analysis, fascin expression was related to worse survival rates (HR = 1.56, P= 0.036), and can be an independent poor prognostic factor in gastric cancer.
- Published
- 2012
30. Patient Perception of Natural Orifice Transluminal Endoscopic Surgery in an Endoscopy Screening Program in Korea
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David W. Rattner, Hyuk-Chan Kwon, Jin-Seok Jang, Byoung-Gwon Kim, Min Chan Kim, and Ki-Han Kim
- Subjects
Laparoscopic surgery ,Adult ,Male ,Natural Orifice Endoscopic Surgery ,medicine.medical_specialty ,medicine.medical_treatment ,surgery ,Young Adult ,Surveys and Questionnaires ,medicine ,Humans ,survey ,Cholecystectomy ,endoscopy ,Korea ,medicine.diagnostic_test ,Gastroenterology & Hepatology ,business.industry ,NOTES ,patient perception ,General Medicine ,Natural orifice transluminal endoscopic surgery ,Middle Aged ,Endoscopy ,Surgery ,Patient perceptions ,Original Article ,Female ,Perception ,business - Abstract
Purpose Natural orifice transluminal endoscopic surgery (NOTES) is a new method of accessing intracavitary organs in order to minimize pain by avoiding incisions in the body wall. The aim of this study is to determine patients' acceptance of NOTES in Korea and to compare their views about laparoscopic surgery and NOTES for benign and malignant diseases. Materials and Methods The target number of total subjects was calculated to be 540. The subjects were classified into 18 sub-groups based on age groups, gender, and history of prior surgery. The questionnaire elicited information about demographic characteristics, medical check-ups, diseases, endoscopic and surgical histories, marital status and childbirth, the acceptance of NOTES, and the preferred routes for NOTES. In addition, the subjects chose laparoscopic surgery or NOTES for a hypothetical cholecystectomy and rectal cancer surgery, and responded to questions regarding the acceptable complication rate of NOTES, the appropriate cost of NOTES, and the reason(s) why they did not select NOTES. Results 486 of 540 patients (90.0%) who agreed to participate in this study completed the questionnaire. NOTES was preferred by the following patients: elderly; a history of treatment due to a disease; having regular check-ups; and a history of an endoscopic procedure (p
- Published
- 2012
31. Comparative Study of Laparoscopy-Assisted versus Open Subtotal Gastrectomy for pT2 Gastric Cancer
- Author
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Ghap-Joong Jung, Ki-Han Kim, Min Chan Kim, and Hyun-Tae Chun
- Subjects
Male ,medicine.medical_specialty ,medicine.medical_treatment ,pT2 gastric cancer ,Gastrectomy ,Stomach Neoplasms ,medicine ,Subtotal gastrectomy ,Humans ,Prospective Studies ,Laparoscopy ,Prospective cohort study ,Survival rate ,Lymph node ,subtotal gastrectomy ,Aged ,medicine.diagnostic_test ,business.industry ,Cancer ,General Medicine ,Middle Aged ,medicine.disease ,Surgery ,Early Gastric Cancer ,medicine.anatomical_structure ,Treatment Outcome ,Oncology ,Original Article ,Female ,business - Abstract
Purpose Laparoscopy-assisted distal gastrectomy (LADG) is a widely accepted surgery for early gastric cancer. However, its use in advanced gastric cancer has rarely been studied. The aim of this study is to investigate the feasibility and survival outcomes of LADG for pT2 gastric cancer. Materials and methods Between January 2004 and December 2009, we evaluated 67 and 52 patients who underwent open distal gastrectomy (ODG) and LADG, respectively, with diagnosis of pT2 gastric cancer. The clinicopathological characteristics, postoperative outcomes, and survival were retrospectively compared between the two groups. Results There were statistically significant differences in the proximal margin of the clinicopathological parameters. The operation time was significantly longer in LADG than in ODG (207.7 vs. 159.9 minutes). There were 6 (9.0%) and 5 (9.6%) complications in ODG and LADG, respectively. During follow-up periods, tumor recurrence occurred in 7 (10.4%) patients of the ODG and in 4 (7.7%) patients of the LADG group. The 5-year survival rate of ODG and LADG was 88.6% and 91.3% (p=0.613), respectively. In view of lymph node involvement, 5-year survival rates were 96.0% in ODG versus 97.0% in LADG for patients with negative nodal metastasis (p=0.968) and 80.9% in ODG versus 78.7% in LADG for those with positive nodal metastasis (p=0.868). Conclusion Although prospective study is necessary to compare LADG with open gastrectomy for the treatment of advanced gastric cancer, laparoscopy-assisted distal gastrectomy might be considered as an alternative treatment for some pT2 gastric cancer.
- Published
- 2012
32. Formation of Dual Threshold in a Vertical Alignment Liquid Crystal Device
- Author
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Sun-Wook Choi, Huilian Jin, Ki-Han Kim, Hee Seop Kim, Ji-Hoon Lee, Hoon Kim, Tae-Hoon Yoon, and Ki-Chul Shin
- Subjects
chemistry.chemical_classification ,Materials science ,business.industry ,Polymer ,Atomic and Molecular Physics, and Optics ,Threshold voltage ,Vertical alignment ,Optics ,chemistry ,Liquid crystal ,Optoelectronics ,Dual threshold ,Contrast ratio ,business ,Voltage drop ,Voltage - Abstract
We present a method that enables dual threshold voltages in a vertical alignment liquid crystal device, through which the gamma shift can be reduced with no subsequent decrease in the contrast ratio. By forming polymer layers, the threshold voltage shift is accomplished through the utilization of the voltage drop effect. We expect that the proposed method can be applied to the conventional 4-domain mode in order to achieve an 8-domain mode without the need for complex driving schemes.
- Published
- 2012
33. High-transmittance Multi-domain Vertical Alignment Liquid Crystal Device with Protrusion Structure
- Author
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Hoon Kim, Ki-Han Kim, Dong Han Song, Eun-Young Jeon, Byung Wok Park, Hee Seop Kim, Ki-Chul Shin, Tae-Hoon Yoon, and Sun-Wook Choi
- Subjects
Liquid-crystal display ,Materials science ,business.industry ,Structure (category theory) ,Substrate (electronics) ,Disclination ,Atomic and Molecular Physics, and Optics ,law.invention ,Optics ,Dark state ,Liquid crystal ,law ,Electric field ,Transmittance ,business - Abstract
We propose a high-transmittance multi-domain vertical alignment liquid crystal device with a protrusion structure. Disclination lines, which inevitably appear at the boundaries of domains in a multi-domain structure, can be reduced by adding a protrusion structure on the top substrate. The transmittance was improved by 11% using the proposed structure with no change of either the dark state or the operating voltage.
- Published
- 2012
34. Comparative Study of Hand-Sutured versus Circular Stapled Anastomosis for Gastrojejunostomy in Laparoscopy Assisted Distal Gastrectomy
- Author
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Su Hyun Seo, Min Chan Kim, Ghap Joong Jung, Hong-Jo Choi, and Ki Han Kim
- Subjects
Billroth II ,Stapled anastomosis ,Billroth-II ,Cancer Research ,medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,medicine.medical_treatment ,Distal gastrectomy ,Gastroenterology ,Anastomosis ,Surgery ,Oncology ,medicine ,Clinicopathological features ,In patient ,Gastrectomy ,Original Article ,Laparoscopy ,Staple ,business ,Gastric cancer - Abstract
Purpose: Mechanical stapler is regarded as a good alternative to the hand sewing technique, when used in gastric reconstruction. The circular stapling method has been widely applied to gastrectomy (open orlaparoscopic), for gastric cancer. We illustrated and compared the hand-sutured method to the circular stapling method, for Billroth-II, in patients who underwent laparoscopy assisted distal gastrectomy for gastric cancer. Materials and Methods: Between April 2009 and May 2011, 60 patients who underwent laparoscopy assisted distal gastrectomy, with Billroth-II, were enrolled. Hand-sutured Billroth-II was performed in 40 patients (manual group) and circular stapler Billroth-II was performed in 20 patients (stapler group). Clinicopathological features and post-operative outcomes were evaluated and compared between the two groups. Results: Nosignificant differences were observed in clinicopathologic parameters and post-operative outcomes, except in the operation times. Operation times and anastomosis times were significantly shorter in the stapler group (P=0.004 and P
- Published
- 2012
35. A 1.6 V 1.4 Gbp/s/pin Consumer DRAM With Self-Dynamic Voltage Scaling Technique in 44 nm CMOS Technology
- Author
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Young-Kyoung Choi, Young-Jung Choi, Nak-Kyu Park, Ju-Hwan Shon, Chulwoo Kim, Ki-Han Kim, Byong-Tae Chung, Hyun-woo Lee, and Kwan-Weon Kim
- Subjects
Engineering ,business.industry ,DDR2 SDRAM ,Clock gating ,Dynamic voltage scaling ,Process variation ,CMOS ,Low-power electronics ,Timing margin ,Hardware_INTEGRATEDCIRCUITS ,Electronic engineering ,Electrical and Electronic Engineering ,business ,Dram - Abstract
A 512 Mbit consumer DDR2 SDRAM that uses self-dynamic voltage scaling (SDVS) and adaptive design techniques is introduced in this paper. With the increase in the significance of process variation, higher performance requirements reduce the allowable design margin in DRAM circuits. However, self-dynamic voltage scaling gives a greater timing margin in the circuitry by changing the internal supply voltage in response to the operating frequency and process skew. By changing the internal supply voltage, the life time of the chip increases by more than 23 times when the supply voltage is lowered by 300 mV. The proposed adaptive design techniques include an adaptive bandwidth delay-locked loop and an adaptive clock gating. The former improves the performance by obtaining a wider valid data window and the latter saves on dynamic power consumption in the clock distribution network. The SDVS method reduces the IDD3P by 9.3% and the adaptive clock gating saves 8.8% of the IDD3N when measured at 200 MHz, 25°C The studied consumer DDR2 SDRAM was fabricated using 44 nm standard DRAM process technology. It occupies a 17.7 mm2 die area and operates using a 1.8 V power supply.
- Published
- 2012
36. Comparative Analysis of Five-Year Survival Results of Laparoscopy-Assisted Gastrectomy versus Open Gastrectomy for Advanced Gastric Cancer: A Case-Control Study Using a Propensity Score Method
- Author
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Hyukchan Kwon, Min Chan Kim, Ki-Han Kim, Hongjo Choi, Ghap-Joong Jung, and Jin-Seok Jang
- Subjects
Adult ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,Kaplan-Meier Estimate ,Risk Assessment ,Disease-Free Survival ,Postoperative Complications ,Gastrectomy ,Stomach Neoplasms ,Laparotomy ,Confidence Intervals ,medicine ,Humans ,Neoplasm Invasiveness ,Laparoscopy ,Survival analysis ,Aged ,Neoplasm Staging ,Proportional Hazards Models ,Retrospective Studies ,medicine.diagnostic_test ,Proportional hazards model ,business.industry ,General surgery ,Biopsy, Needle ,Gastroenterology ,Case-control study ,Retrospective cohort study ,Middle Aged ,Advanced gastric cancer ,Immunohistochemistry ,Survival Analysis ,Surgery ,Treatment Outcome ,Case-Control Studies ,Lymph Node Excision ,Female ,Lymph Nodes ,Patient Safety ,business ,Follow-Up Studies - Abstract
The aim of this study was to investigate the surgical and oncologic outcomes of laparoscopy-assisted gastrectomy (LAG) and open gastrectomy (OG) for advanced gastric cancer (AGC) using the case-control method with a sufficient follow-up period.The authors retrospectively analyzed 89 patients who underwent LAG and 345 patients who underwent OG for AGC between August 1999 and June 2007. A total of 176 matched cases were included in the final analysis.Except for tumor size and reconstruction, there were no statistically significant differences in the clinicopathological parameters between the two groups. Although operation time was significantly longer for LAG than OG (228.3 vs. 183.6 min, p0.0001), first flatus time and postoperative hospital stay without complications were significantly shorter in the LAG group (3.2 vs. 3.7 days, p0.0001; 7.0 vs. 10.4 days, p0.0001, respectively). Operation-related complications occurred in 7 cases (8.0%) in both groups. 13 patients (14.8%) in the LAG group and 15 patients (17.1%) in the OG group had recurrence. There was no statistically significant difference in the 5-year and disease-free survival rates between LAG and OG.LAG for AGC might be considered to be a minimally invasive surgery in some selected cases, although a well-designed prospective study comparing LAG with OG for AGC is needed.
- Published
- 2012
37. Vertical alignment nematic liquid crystal cell controlled by double-side in-plane switching with positive dielectric anisotropy liquid crystal
- Author
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Hun Ki Shin, Ki-Han Kim, Tae-Hoon Yoon, and Jae Chang Kim
- Subjects
Anisotropy -- Analysis ,Dielectrics -- Evaluation ,Liquid crystals -- Structure ,Liquid crystals -- Electric properties ,Physics - Abstract
A vertical alignment (VA) liquid crystal cell is proposed that is controlled by double-side in-plane switching (DSIPS) with a positive dielectric anisotropy liquid crystal material. The studies have shown that the DSIPS cell has a large misalignment tolerance and wide viewing angle property with negative C film and the total response time of the DSIPS cell is as fast as that of the conventional VA-IPS cell.
- Published
- 2008
38. Comparative Study of Complete and Partial Omentectomy in Radical Subtotal Gastrectomy for Early Gastric Cancer
- Author
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Min Chan Kim, Ghap Joong Jung, David W. Rattner, and Ki-Han Kim
- Subjects
Male ,medicine.medical_specialty ,Partial omentectomy ,medicine.medical_treatment ,post-operative outcome ,Partial Omentectomy ,Gastroenterology ,Gastrectomy ,Stomach Neoplasms ,Internal medicine ,Medicine ,Humans ,Laparoscopy ,comparative study ,Aged ,Retrospective Studies ,medicine.diagnostic_test ,business.industry ,Stomach ,gastric cancer ,Retrospective cohort study ,General Medicine ,Greater omentum ,Middle Aged ,Surgery ,Early Gastric Cancer ,Omentectomy ,medicine.anatomical_structure ,Treatment Outcome ,Original Article ,Female ,business ,Omentum - Abstract
PURPOSE Curative surgery for patients with advanced or even early gastric cancer can be defined as resection of the stomach and dissection of the first and second level lymph nodes, including the greater omentum. The aim of this study was to evaluate the short- and long- term outcomes of partial omentectomy (PO) as compared with complete omentectomy (CO). MATERIALS AND METHODS Seventeen consecutive open distal gastrectomies with POs were initially performed between February and July in 2006. The patients' clinicopathologic data and post-operative outcomes were retrospectively compared with 20 patients who underwent open distal gastrectomies with COs for early gastric cancer in 2005. RESULTS The operation time in PO group was significantly shorter than that in CO group (142.4 minutes vs. 165.0 minutes, p=0.018). The serum albumin concentration on the first post-operative day in PO group was significantly higher than CO group (3.8 g/dL vs. 3.5 g/dL, p=0.018). Three postoperative minor complications were successfully managed with conservative treatment. Median follow-up period between PO and CO was 38.1 and 37.7 months. All patients were alive without recurrence until December 30, 2009. CONCLUSION PO during open radical distal gastrectomy can be considered a more useful procedure than CO for treating early gastric cancer. To document the long-term technical and oncologic safety of this procedure, a large-scale prospective randomized trial will be needed.
- Published
- 2011
39. Dye-doped liquid crystal device switchable between reflective and transmissive modes
- Author
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Tae-Hoon Yoon, Huilian Jin, Jae Chang Kim, Hye-Jung Jin, and Ki-Han Kim
- Subjects
Optics ,Materials science ,business.industry ,Liquid crystal ,Dichroic dye ,Optoelectronics ,General Materials Science ,Electrical and Electronic Engineering ,Division (mathematics) ,business ,Reflectivity ,Layer (electronics) ,Dye doped - Abstract
A liquid crystal (LC) device switchable between the reflective and transmissive modes without sub-pixel division is proposed. By using dye-doped nematic LCs for the top LC layer, transflective displays with high reflectance were realized. It is expected that the proposed device can be applied to high-reflectance transflective devices for outdoor applications.
- Published
- 2011
40. Clinicopathologic significance of ERCC1, thymidylate synthase and glutathione S-transferase P1 expression for advanced gastric cancer patients receiving adjuvant 5-FU and cisplatin chemotherapy
- Author
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Suee Lee, Hyo-Jin Kim, Hyukchan Kwon, Jin Seok Jang, Ki Han Kim, Sung Yong Oh, Su Jin Kim, Min Chan Kim, Sung-Hyun Kim, and Kyung A Kwon
- Subjects
Adult ,Male ,Oncology ,medicine.medical_specialty ,Health, Toxicology and Mutagenesis ,medicine.medical_treatment ,Clinical Biochemistry ,Biochemistry ,Thymidylate synthase ,Disease-Free Survival ,Young Adult ,GSTP1 ,Stomach Neoplasms ,Internal medicine ,medicine ,Humans ,neoplasms ,Survival analysis ,Aged ,Neoplasm Staging ,Cisplatin ,Chemotherapy ,biology ,business.industry ,Thymidylate Synthase ,Middle Aged ,Endonucleases ,Prognosis ,Survival Analysis ,DNA-Binding Proteins ,Treatment Outcome ,Glutathione S-transferase ,Glutathione S-Transferase pi ,biology.protein ,Female ,Fluorouracil ,Lymph Nodes ,ERCC1 ,business ,Adjuvant ,Biomarkers ,medicine.drug - Abstract
The objective of this study was to determine whether the expressions of the excision cross-complementing (ERCC1), thymidylate synthase (TS) and glutathione S-transferase P1 (GSTP1) are predictive of clinical outcomes in advanced gastric cancer (AGC) patients receiving treatment with adjuvant 5-fluorouracil (5-FU) and cisplatin (FP) chemotherapy. One hundred forty nine patients were included in this study. ERCC1 and GSTP1 expression was correlated significantly with tumor size (p = 0.040, p = 0.018, respectively). Stage and positive lymph node ratio were associated independently with disease free survival (DFS) and overall survival (OS). Both ERCC1 and GSTP1 expression had a significant impact on OS (hazard ratio = 0.069, p = 0.021). TS expression was not related to DFS and OS.
- Published
- 2010
41. Adjuvant chemoradiation versus chemotherapy in completely resected advanced gastric cancer with D2 nodal dissection
- Author
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Sunghyun Kim, Min Chan Kim, Sung Yong Oh, Hyo-Jin Kim, Suee Lee, Kyung A Kwon, Hyuk-Chan Kwon, Ki Han Kim, Jin Seok Jang, and Hyung Sik Lee
- Subjects
Chemotherapy ,medicine.medical_specialty ,Nausea ,business.industry ,medicine.medical_treatment ,Cancer ,General Medicine ,Neutropenia ,medicine.disease ,Surgery ,Capecitabine ,Radiation therapy ,Oncology ,medicine ,Gastrectomy ,medicine.symptom ,business ,Survival rate ,medicine.drug - Abstract
Aim: Adjuvant chemoradiation has become a standard of care in the USA. We evaluated the efficacy and toxicity of adjuvant chemoradiation versus chemotherapy in completely resected locally advanced gastric cancer. Methods: Patients with stage IIIA, IIIB and IV (without metastasis) gastric cancer were treated with chemoradiation and 5-fluorouracil/cisplatin (FP) (arm A) or FP (arm B). Arm A consisted of one cycle of FP followed by 4500 cGY to radiation field with capecitabine. One month after completion of radiotherapy, patients received three additional cycles of FP every 3 weeks. Arm B consisted of six cycles of FP. Results: A total of 61 patients were enrolled, of whom 31 were placed in arm A and 30 in arm B. The median follow-up duration was 77.2 months (range 24–92.8 months). We did not find any difference in 3-year disease-free survival between arm A and B (80.0 vs 75.2%, respectively; P = 0.887). There was no significant difference between the arms in 5-year disease-free survival (76.7 vs 59.1%, respectively; P = 0.222) or overall survival (70.1 vs 70.0%, respectively; P = 0.814). Seven patients (22.6%) relapsed in arm A and 12 patients (40%) relapsed in arm B. Grade 3/4 neutropenia occurred in 48.5% of patients in arm A and 22.9% in arm B. Grade 3 nausea or vomiting occurred in 6% in arm A and 14.6% in arm B. Conclusion: We could not make any conclusion about the benefit of adding radiation to adjuvant chemotherapy.
- Published
- 2010
42. Fast Switching of a Polymer-networked Twisted Nematic Liquid Crystal Cell
- Author
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Jae Chang Kim, Tae-Hoon Yoon, Hye-Jung Jin, Jong-In Baek, and Ki-Han Kim
- Subjects
chemistry.chemical_classification ,Liquid-crystal display ,Materials science ,business.industry ,Cell ,Response time ,Polymer ,law.invention ,Optics ,medicine.anatomical_structure ,chemistry ,law ,Liquid crystal ,Transmittance ,medicine ,Anisotropy ,business ,Backflow - Abstract
We propose a method to enhance the response time of a twisted nematic liquid crystal (TN-LC) cell using an anisotropic polymer. Polymer networks are formed by the phase separation between a LC and a UV-curable polymer. A TN-LC cell is exposed to UV light after the mixture of LC and anisotropic polymer is injected into the TN-LC cell. As a result, turn-off time of a TN-LC cell can be decreased remarkably without any loss of the transmittance. The turn-off time of a TN-LC cell with pure LC was 16 ms, but those of polymer networked TN-LC cells were 12, 11, and 9 ms when the concentration of the polymer was 3, 5, and 10 wt%, respectively. Moreover, by virtue of the polymer network, the backflow effect and the delay time generated during the turn-off process disappeared.
- Published
- 2010
43. Viewing Angle Control of a Hybrid-Aligned Liquid Crystal Display
- Author
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Jong-In Baek, Jae Chang Kim, Tae-Hoon Yoon, and Ki-Han Kim
- Subjects
Liquid-crystal display ,Materials science ,business.industry ,Optical transmittance ,General Chemistry ,Condensed Matter Physics ,Viewing angle ,law.invention ,Optical axis ,Optics ,Tilt (optics) ,law ,Liquid crystal ,Electrode ,General Materials Science ,business - Abstract
A method for viewing angle control of a hybrid-aligned liquid crystal (LC) cell is reported. The viewing angle of proposed structure can be controlled by using vertical switching, by which the tilt angle of LC is controlled, while the optical transmittance can be controlled by using horizontal switching, by which the optic axis (OA) of LC can be rotated. A 3-terminal electrode structure composed of the top common electrode, the bottom grid electrodes, and the bottom common electrode is employed for both the vertical switching and the horizontal one.
- Published
- 2009
44. Possible Correlations among Mountaineering Experiences, Leisure Identity and Psychologic Well-being
- Author
-
Gwang Geol Han and Ki Han Kim
- Subjects
Mountaineering ,Well-being ,Identity (social science) ,Psychology ,Social psychology - Published
- 2008
45. Electromagnetic Design and Performance Evaluation of an MR Valve
- Author
-
Ki-Han Kim, Yun-Joo Nam, and Myeong-Kwan Park
- Subjects
Engineering ,Magnetic reluctance ,business.industry ,Mechanical Engineering ,Acoustics ,Magnetic flux ,Magnetic field ,Magnetic circuit ,Fluid power ,Electromagnetic coil ,Magnetorheological fluid ,Electronic engineering ,business ,Yoke - Abstract
This paper presents an electromagnetic design method for magneto-rheological (MR) valves. Since the apparent viscosity of MR fluids is adjusted by applying magnetic fields, the MR valves can control high-level fluid power without any mechanical moving parts. In order to improve the performances of the MR valve, it is important that the magnetic field is effectively supplied to the MR fluid. For the purpose, the magnetic circuit composed with the yoke for forming magnetic flux path, the electromagnetic coil and the MR fluid should be well designed. In order to improve the static characteristic of the MR valve, the length of the magnetic flux path is decreased by removing the unnecessary bulk of the yoke. Also, in order to improve its dynamic and hysteretic characteristics, the magnetic reluctance of the magnetic circuit should be increased by minimizing the cross-sectional area of the yoke through which the magnetic flux passes. After two MR valves, one is a conventional type valve and the other is the proposed one, are designed and fabricated, their performances are evaluated experimentally.
- Published
- 2008
46. An Optical Configuration for the Normally Black Twisted Nematic Liquid Crystal Cell
- Author
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Jong-In Baek, Ki-Han Kim, Jae Chang Kim, and Tae-Hoon Yoon
- Subjects
Materials science ,Liquid-crystal display ,Dark state ,Optics ,law ,business.industry ,Liquid crystal ,Dispersion (optics) ,Diagram ,Bright state ,Parameter space ,business ,law.invention - Abstract
We propose an optical configuration to compensate dispersion characteristics in the dark state of normally black twisted nematic (NB-TN) liquid crystal display (LCD). We employed a half-wave plate (HWP) and a +A plate to achieve the superior dark state. By using the parameter space diagram (PSD) method, we could obtain the optimum values of parameters and the high contrast-ratio over 500 : 1 could be obtained. Furthermore, excellent dispersion characteristics were also obtained in the bright state. We could confirm the performance of the proposed structure using both the numerical calculations and the experiments.
- Published
- 2008
47. Advanced Experimental and Numerical Techniques for Cavitation Erosion Prediction
- Author
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Ki-Han Kim, Georges Chahine, Jean-Pierre Franc, Ayat Karimi, Ki-Han Kim, Georges Chahine, Jean-Pierre Franc, and Ayat Karimi
- Subjects
- Cavitation erosion, Cavitation
- Abstract
This book provides a comprehensive treatment of the cavitation erosion phenomenon and state-of-the-art research in the field. It is divided into two parts. Part 1 consists of seven chapters, offering a wide range of computational and experimental approaches to cavitation erosion. It includes a general introduction to cavitation and cavitation erosion a detailed description of facilities and measurement techniques commonly used in cavitation erosion studies, an extensive presentation of various stages of cavitation damage (including incubation and mass loss) and insights into the contribution of computational methods to the analysis of both fluid and material behavior. The proposed approach is based on a detailed description of impact loads generated by collapsing cavitation bubbles and a physical analysis of the material response to these loads. Part 2 is devoted to a selection of nine papers presented at the International Workshop on Advanced Experimental and Numerical Techniques for Cavitation Erosion Prediction (Grenoble, France, 1-2 March 2011) representing the forefront of research on cavitation erosion. Innovative numerical and experimental investigations illustrate the most advanced breakthroughs in cavitation erosion research.
- Published
- 2014
48. Analysis of Children's Motivation to Participate in After-School Basketball Class
- Author
-
Jeong Kyeong Kim and Ki Han Kim
- Subjects
Class (computer programming) ,Basketball ,Mathematics education ,Psychology - Published
- 2007
49. Laparoscopic Management of a Primary Small Bowel Volvulus
- Author
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Sung-Heun Kim, Ki-Han Kim, Ki-Jae Park, Min Chan Kim, and Ghap-Joong Jung
- Subjects
Male ,Gangrene ,Torsion Abnormality ,medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Middle Aged ,medicine.disease ,digestive system diseases ,Small intestine ,Surgery ,Peritoneal cavity ,medicine.anatomical_structure ,Small bowel volvulus ,medicine ,Terminal ileum ,Humans ,Laparoscopy ,Tomography, X-Ray Computed ,business ,Intestinal Volvulus ,Abdominal surgery - Abstract
Primary small bowel volvulus in adults is a very rare condition, and it is defined as torsion of all or a large segment of the small intestine and its mesentery in the absence of any preexisting etiologic factors. Proper management of the patients suffering from a strangulated obstruction depends on making an early and accurate diagnosis. Timely treatment is crucial to prevent gangrene. A 49-year-old man who had a history of previous abdominal surgery was admitted to our hospital with complaints of acute abdominal pain. Simple abdominal x-ray showed multiple dilated loops of small intestine in the mid-abdomen. Enhanced abdominal computed tomography showed the distended small bowel loops and longitudinal tapering of the collapsed bowel loops. We carried out diagnostic laparoscopy to confirm the cause of suspected mechanical ileus. It revealed strangulation of the small bowel at the terminal ileum due to clockwise torsion of the bowel loop. There were no adhesions or congenital anomalies in the peritoneal cavity. The torsional segment was spontaneously reduced with minimal handling, and the strangulated portion was resected. The patient was discharged from hospital on postoperative day 6. Primary small bowel volvulus in adults is a very rare malady; if the diagnosis is uncertain, then diagnostic laparoscopy is a valuable tool for making the definitive diagnosis and administering prompt treatment.
- Published
- 2007
50. Traumatic Abdominal Wall Hernia (TAWH): A Case Study Highlighting Surgical Management
- Author
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Sung-Heun Kim, Min Chan Kim, Se-Heun Cho, Ghap-Joong Jung, Hong-Jo Choi, Ki-Jae Park, Ki-Han Kim, Young Hoon Kim, and Hak-Youn Lee
- Subjects
Abdominal pain ,medicine.medical_specialty ,Traumatic abdominal wall hernia ,Case Report ,Abdominal Injuries ,Abdominal wall ,medicine ,Hollow viscus ,Humans ,Hernia ,primary closure ,business.industry ,Abdominal wall defect ,Abdominal Wall ,General Medicine ,Middle Aged ,medicine.disease ,Surgery ,Hernia, Abdominal ,medicine.anatomical_structure ,Treatment Outcome ,Abdomen ,Female ,Radiology ,medicine.symptom ,business ,Tomography, X-Ray Computed ,Abdominal surgery ,Exploratory surgery - Abstract
We report a rare case of traumatic abdominal wall hernia (TAWH) caused by a traffic accident. A 47-year-old woman presented to the emergency room soon after a traffic accident. She complained of diffuse, dull abdominal pain and mild nausea. She had no history of prior abdominal surgery or hernia. We found a bulging mass on her right abdomen. Plain abdominal films demonstrated a protrusion of hollow viscus beyond the right paracolic fat plane. Computed tomography (CT) showed intestinal herniation through an abdominal wall defect into the subcutaneous space. She underwent an exploratory surgery, followed by a layer-by-layer interrupted closure of the wall defect using absorbable monofilament sutures without mesh and with no tension, despite the large size of the defect. Her postoperative course was uneventful.
- Published
- 2007
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