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In order to overcome the limitations of the A* algorithm in the autonomous control of electromagnetically actuated microrobots, this study introduces three modified path planning algorithms (A*-WAPP, A*-waypoints, A*-WAPP-waypoints) using the concept of Wall Avoiding Path Planning (WAPP) and waypoints. Through the autonomous driving experiment of an electromagnetically actuated microrobot, the three modified path planning algorithms based on A* and the original A* algorithm were evaluated using four performance measures. As a result, it was confirmed whether significant changes exist between the A* algorithm and the A*-based modified algorithms about the fitness for the autonomous driving environment of the electromagnetically actuated microrobot. First, compared to the path of the A* algorithm, A*-WAPP algorithm generated a stable path that dramatically reduced the collision between the microrobot and the obstacle. However, in the autonomous driving of the microrobot, A*-WAPP algorithm increased the driving distance and driving time. On the other hand, A*-waypoints algorithm showed a tendency in reducing the driving distance and driving time of the autonomous driving microrobot by simplifying the generated path, but still showed the collision problem between the microrobot and the obstacle. Finally, the path generated by the A*-WAPP-waypoints algorithm greatly increased the stability of the autonomous driving microrobot and showed great advantages of the decreases in the driving distance and driving time. In conclusion, it was confirmed that the proposed A*-WAPP-waypoints algorithm showed the best path generation results in the autonomous driving microrobot among the three A*-based algorithms.

Studies on morbid obesity have shown remarkable improvement of diabetes in patients who have undergone bariatric operations. It was subsequently shown that these operations induce diabetes remission independent of the resultant weight loss; as a result, surgeons began to investigate whether operations for gastric cancer (GC) could have the same beneficial effect on diabetes as bariatric operations. It was then shown in multiple reports that followed that certain operations for GC were able to improve or even cure type 2 diabetes mellitus (T2DM) in GC patients. This finding gave rise to the concept of "oncometabolic surgery", in which a patient diagnosed with both GC and T2DM undergo a single operation with the purpose of treating both diseases. With the increasing incidence of T2DM, oncometabolic surgery has the potential to improve the quality of life and even extend survival of many GC patients. However, because the GC patient population and the bariatric patient population are wildly different and because different GC operations have different properties, the effect of oncometabolic surgery must be carefully assessed and engineered in order to maximize benefit and avoid harm. This manuscript aims to summarize the findings made so far in the field of oncometabolic surgery and to provide an outlook regarding the possibility of oncometabolic surgery being incorporated into standard clinical practice.

Nostalgia has recently garnered attention in the field of leisure, and a leisure nostalgia scale (LNS) has been developed. However, the LNS was initially developed and validated in one Eastern coun...

This paper presents a low-power stacked CMOS image sensor (CIS) in 65/14nm process. With 14nm process, we could achieve 29% less power consumption than the conventional CIS in 65/28nm process. The measured random telegraph noise (RTN) result shows the 65/14nm stacked CIS to guarantee the commercial sensor image quality even though a fin field-effect transistor (FinFET) process is three-dimension channel structure. The pixel array of the implemented chip consists of 12-mega pixels (Mp) with a dual-photodiode (2PD) in 1.4μm pixel pitch, and the sensor output provides 120 frames per second while it consumes 612mW for 12Mp image and 3Mp auto-focus data via a mobile industry processor interface (MIPI) physical layer (DPHY) up to 6.5Gbps/lane. The measured random noise is 2.2e-at 16× analog gain, and figure-of-merit (FoM) of analog-to-digital converters (ADCs) achieves 0.46e-nJ.

Electronic sport games have gained momentum and been applied to many sport contexts for marketing purposes. However, there has been little knowledge about the influence of electronic sports games. The current study approached the problem from this perspective and examined influence of electronic football games (EFG) on four different engagement with physical football (i.e., attendance, participation, viewership, and expenditure). Using the questionnaire, the study examined how people enjoy EFG and participate in traditional football engagements and eventually how playing EFG influence traditional football engagements. A total of 235 questionnaires were collected at ‘PC Rooms’ and ‘PlayStation Rooms’. In an effort to find out the influence of frequency and time of playing EFG on traditional football engagements, a regression technique was used. The results revealed that frequency of playing EFG positively influenced attendance of both K League and Korea national football team matches and also on TV viewership of K League and foreign football leagues. In addition, frequency was strong predictor of football-related merchandise consumption. Frequency of EFG, however, negatively influenced on actual football participation. On the other hands, the amount of time per each gaming did not explained any unique variance in attendance and actual football participation. However, time of EFG significantly predicted TV viewership of both K League and foreign football leagues. Lastly, expenditure of football-related merchandises was positively influenced by the amount of time of playing EFG.

CMOS Image Sensor(CIS) products need higher voltage device and better analog characteristics than conventional SOC & Logic products. This work presents newly developed 14nm FinFET process with 2.xV high voltage FinFET device characteristics showing excellent analog and low power digital characteristics comparing to 28nm planar process. Gm is improved by 30% and 67% in FinFET process for NMOS and PMOS, respectively. Rout characteristics increased by 40 times and 6 times over 28nm planar process. Interface state density(Nit) improved by more than 40% and flicker noise characteristics also improved by 64% and 42% for NMOS and PMOS, respectively. Digital logic Transistor ion-ioff performance improved by by 32% and by 211% for NMOS and PMOS, respectively compared to 28nm planar device and the chip power consumption of digital logic functional block reduced by 34% in real Si of 12M pixel product. 14nm FinFET process expected to improve power consumption by 42% in 144M pixel density.

The design and buckling behavior of earth retaining system supported by high strength steel pipe and PHC pile under compression is presented in this study. Buckling analysis of various strut system was investigated according to the strut total length(30m, 60m, 90m), three types of built-up columns and connection condition. Buckling loads calculated by F.E analysis was compared with the theoretical solution corresponding to diagonal buckling mode, local and global buckling mode of main strut. The design of the built-up column struts are performed based on design guide for high strength steel pipes and P-M diagram for built-up column with two PHC pile section.

Purpose: Recent studies have shown that the procedure of laparoscopic appendectomy requires a learning curve before mastering. The aim of this study was to investigate the question of whether a surgeon who has been working as a first assistant for training in laparoscopic colorectal surgery can perform laparoscopic appendectomy without previous experience as an operator in laparoscopic appendectomy. Methods: Ninety consecutive patients who underwent laparoscopic appendectomy by a single surgeon were retrospectively enrolled in this study. The operating surgeon completed fellowship training of the colorectal cancer division as a first assistant for two years. The patients were divided into two groups by consecutive order: Group (A) included the initial 45 patients and Group (B) included the next 45 patients. The clinical patient demographics, histological diagnosis, and outcome variables including operation time, conversion to open surgery, complications, and length of hospital stay were compared between the two groups. Results: No difference in operation time was observed between the groups (mean: 58.22 min vs 66.6 min, p=0.097). Open conversion rate and drain insertion rate were similar between the two groups. There was no difference in length of hospital stay. Overall complication rate did not differ between the two groups. Moving average curve showed no specific time shortening point within these 90 enrolled patients. Conclusion: This study demonstrates that laparoscopic appendectomies performed by a surgeon who had achieved a training course as an assistant in laparoscopic colorectal surgery were performed safely without any difficulties during the learning period. This finding needs further validation in additional large-scale studies.

파이토케미칼이 암 세포 성장에 미치는 영향을 확인하기 위하여, 대장암 세포주 HCT116에 네 종류의 파이토케미칼을 각각 25 μM의 농도로 처리하였다. 처리한 파이토케미칼 중 curcumin이 가장 강력하게 세포 성장을 억제하였다. 또한 curcumin은 농도의존적으로 세포 성장을 억제하였다. Curcumin에 의한 대장암 세포주 성장저해 활성에 대한 분자생물학적 기전을 연구하기 위하여 oligo DNA microarray 실험을 수행하였다. 그 결과, 25 μM curcumin 처리에 의해 2배 이상 발현이 증가된 유전자 137개, 발현이 감소된 유전자 141개를 선별하였다. 발현이 증가된 유전자 중, 세포사멸과 밀접한 관련이 있는 것으로 알려진 유전자 3개를 선택하여, RT-PCR을 통해 이들 유전자의 발현이 감소됨을 확인하였다. 처리한 파이토케미칼 중 curcumin은 가장 강력한 ATF3의 유도자였으며, 농도의존적으로 ATF3의 발현을 증가시켰다. 흥미롭게도, curcumin에 의한 성장 저해는 ATF3-siRNA에 의한 ATF3 유전자 발현감소에 의해 성장이 회복되었다. 또한, ATF3 유전자의 과대발현 후 발현이 변화되는 유전자를 선별한 결과, 세포사멸과 관련된 많은 유전자들이 증가됨을 확인하였다. 결론적으로, 대장암 세포주에서 curcumin에 의한 항 성장활성에 있어서 ATF3 유전자가 중요한 역할을 할 것으로 생각된다.

The effects of genistein on cell proliferation and adipogenesis were examined in mouse 3T3-L1 preadipocyte cells. Genistein decreased viability of 3T3-L1 pre-adipocytes in a dose-dependent manner. Oil Red O staining of these cells also indicated that adipogenesis was inhibited by 50 genistein treatment. We investigated the molecular mechanisms involved in the decrease in cell viability in genistein-treated 3T3-L1 cells by conducting an oligo DNA microarray analysis. We selected the sirtuin-1 gene, one of the upregulated genes, for further experimentation because sirtuin-1 belongs to the sirtuin family, which is associated with anti-obesity and anti-inflammation activities. We found that four phytochemicals (resveratrol, capsaicin, daidzein, and genistein) could increase sirtuin-1 expression. Genistein was the strongest inducer of sirtuin-1 among the tested phytochemicals. The inhibition of adipogenesis by genistein was recovered by surtuin-1 siRNA transfection. Overall, these results may further our understanding of the molecular mechanisms underlying the inhibition of proliferation and adipogenesis by genistein in mouse 3T3-L1 cells.

This paper proposes a low-power 240 frames/s 2.1 M-pixel CMOS image sensor with column-shared cyclic (CY) ADCs. Two-column shared CY-ADC architecture and two-level stacked ADC placement are employed for low-power and small pixel pitch design. The proposed CY-ADC uses only one OTA and four capacitors. Distributed clocking scheme using cascaded repeaters is proposed to reduce the required peak current. The prototype sensor was fabricated in a 0.13- μm 1P4M process with pixel pitch of 2.25 μm . The designed 10-bit ADC dissipates only 90 μW/channel with 1.5 V supply. The measured DNL and INL are +0.59/-0.83 LSB and +2.8/-3.6 LSB, respectively. The measured maximum pixel rate is 500 Mpixels/s with total power consumption of 300 mW.

This paper presents a 2.1 M pixel, 120 frame/s CMOS image sensor with column-parallel delta-sigma (ΔΣ) ADC architecture. The use of a second-order ΔΣ ADC improves the conversion speed while reducing the random noise (RN) level as well. The ΔΣ ADC employing an inverter-based ΔΣ modulator and a compact decimation filter is accommodated within a fine pixel pitch of 2.25-μm and improves energy efficiency while providing a high frame-rate of 120 frame/s. A prototype image sensor has been fabricated with a 0.13-μm CMOS process. Measurement results show a RN of 2.4 erms- and a dynamic range of 73 dB. The power consumption of the prototype image sensor is only 180 mW. This work achieves the energy efficiency of 1.7 e-·nJ.

This research aims to develop polymer composites which can be used for PEMFC separators by injection molding process. Considering the moldability and stiffness, we used PPS(Poly(phenylene sulfide)) and PP(Polypropylene) as base resin. In order to improve electrical conductivity and physical properties, we chose glass fiber, carbon fiber, carbon black, and both expanded graphite and synthetic graphite. The 3 type composites are prepared for injection molding of PEMFC separators. and CAE(Computer Aided Engineering) analysis was conducted to optimize injection processing parameters(injection pressure, heat time, mold temperature etc.). We did successfully fabricate the separators by injection molding, and measure the electrical conductivity of the samples by using four point probe device. Conclusively, PP/SG/CB composite showed better both electrical conductivity and moldability than the others. Key Words : PEMFC, Separator, Injection Molding, Compression Injection Molding, E-MOLD, CAE Analysis

In the present study, we investigated anti-proliferative activities of capsaicin and gene expression changes in response to capsaicin treatment in human colorectal HCT116 cells. The results showed that capsaicin decreased cell viabilities in a dose dependent manner and induced global gene expression changes. We found that 103 genes were up-regulated more than twofold, whereas 153 genes were down-regulated more than twofold by capsaicin treatment. Among the up-regulated genes, we selected 4 genes (NAG-1, DDIT3, GADD45A and PCK2) and performed RT-PCR to confirm the microarray data. We found that of capsaicin increased tumor suppressor p53 gene expression. In addition, the results showed that NAG-1, DDIT3 and GADD45A expressions were not dependent on p53 presence, whereas PCK2 expression. The results of this study may help to increase our understandings of the molecular mechanism of anti-proliferative activity mediated by capsaicin in human colorectal cancer cells.

Light-section (LS)-based range finders are commonly used for obstacle recognition in home service robots and autonomous vehicles. This paper proposes a smart CMOS image sensor for LS-based range finding. The proposed sensor can detect the laser light, even under very strong ambient-illumination levels by using a multiple-capture frame-correlated double sampling (F-CDS), which is realized with an inverter-based switched-capacitor F-CDS accumulator. The proposed sensor also includes on-chip winner-take-all circuits that significantly reduce the software and hardware complexity of interpolation for the subpixel resolution. The prototype chip was fabricated using a 0.35-mum CMOS process. The measurement results show that the proposed sensor can detect a laser line with an intensity that is 56.5 dB lower than that of the ambient illumination, providing a spatial resolution of plusmn0.16 pixels.

To investigate whether isoflavone genistein and daidzein could affect cancer cell viability, human colorectal HCT116 cells were incubated with genistein or daidzein in a dose-dependent manner. Genistein decreased cancer cell viability in a dose-dependent manner, whereas daidzein did not show dramatic cytotoxic effects. We also found that 71 genes were up-regulated more than 2-fold, whereas 64 genes were down-regulated more than 2-fold with 24 hr of genistein treatment by our previous microarray data. Among the up-regulated genes, we selected 3 genes (DKK1, ATF3 and NAG-1) and performed RT-PCR to confirm microarray data. The results of RT-PCR were highly correlated with those of the microarray experiment. In addition, we investigated whether a combination treatment of genistein and daidzein could affect cancer cell viability. Surprisingly, the combination treatment did show synergistic cytotoxic effects detected by MTS assay. The results of RT-PCR and real-time PCR indicate that a combination of genistein and daidzein can synergistically induce NAG-1 expression in HCT116 cells. This result implies that NAG-1 induction is highly associated with synergistic cytotoxic effects induced by a combination treatment of genistein and daidzein. Overall, these results may provide a clue in explaining the anti-cancer activity of soy bean in human colorectal cancer.

This paper proposes a column-parallel two-step single-slope (SS) ADC for high-speed CMOS image sensors. Error correction scheme to improve the linearity is proposed as well. A prototype sensor of 320 times 240 pixels has been fabricated with a 0.35-mum CMOS process. Measurement results demonstrate that the proposed ADC can achieve the conversion time of 4 mus , which is ten times faster than the conventional SS ADC. The proposed error correction effectively removes the dead band problem and yields DNL of +0.53/ -0.78 LSB and INL of +1.42/ -1.61 LSB. The power consumption is 36 mW from a supply voltage of 2.8 V.

In this study, the concept of the ultrasonic active fiber sensor (UAFS) system based on the pulse-echo method was newly proposed for several mechanical and environmental sensors. A piezoelectric transducer, which was attached onto the end of the optical fiber, can be used for the ultrasonic wave generator and receiver. The piezoelectric patch was excited at its resonance frequency in the direction of length to generate the longitudinal ultrasonic wave, and was used for sensing the reflected signal on the end of the optical fiber. The emitted ultrasonic wave was propagated along the optical fiber and then reflected by a mechanical stimulus on the way. The time interval of the reflected ultrasonic wave was used to predict the location of the stimulus from the piezoelectric transducer. The UAFS was applied to monitor the cure conditions and to measure liquid level. In terms of the attenuation of the ultrasonic wave by the damping properties and the degree of coupling between the surrounding medium, the cure condition of the solder was successfully monitored and the water level was measured based on the linear relationship between liquid height and output signal.

A piezoelectric ultrasonic sensing system based on an optical fiber has been developed for two-phase flow monitoring. The ultrasonic wave generated from a piezoelectric actuator is guided and propagated in the optical fiber and then sensed by a piezoelectric sensor located at the other end of the fiber. The sensed signal can be influenced by environmental and physical changes around the optical fiber. For this study, the sensitivity of the optical fiber sensor is experimentally studied according to the system parameters, such as fiber coating, frequency, and the number of cycles of the input voltage signal to the piezoelectric actuator. The developed sensing system is applied for monitoring the void fraction of the two-phase flow and the feasibility as a two-phase flow monitoring system is demonstrated.

An eye tracker is a system that detects the point where the user gazes on. The conventional eye tracker using a charge-coupled device (CCD) camera needs many peripherals, software computation causing high cost, computation time and power consumption. This paper proposes a single-chip eye tracker using smart CMOS image sensor (CIS) pixels. The proposed eye tracker does not require additional peripherals and operates at higher speed than the conventional approach. The prototype chip was designed and fabricated for a 32/spl times/32 smart CIS pixels array with a 0.35-/spl mu/m CMOS process. The test results show /spl plusmn/ 1 pixel error at the rate of 125 frame-per-second. The power consumption is 260 mW with 3.3 V supply voltage and the silicon area is 3.8 mm/sup 2/.

This letter proposes a mismatch insensitive switched-capacitor multiply-by-four (4X) amplifier using the voltage addition scheme. The proposed circuit provides 2-times faster speed and about half of silicon area when compared with the cascade of conventional 2X amplifiers. Monte-Carlo simulation results show about 15% gain accuracy improvement over the cascaded 2X- amplifiers.

An image sensor has limited dynamic range while the human eye has a logarithmic response over a wide range of light intensity. Although the sensor gain can be set high to identify details in darker areas on an image, this high gain results in saturation in brighter areas. Therefore, gamma correction is essential to match the human eye response. However, the digital gamma correction degrades image quality, especially for darker areas on the image, due to the limited resolution and dynamic range of the analog-to-digital converter (ADC). In this paper, we propose a complementary metal–oxide–semiconductor (CMOS) image sensor (CIS) with a compact nonlinear ADC which performs analog gamma corrections that use the full dynamic range. A CIS with the proposed nonlinear ADC was fabricated with a 0.35-µm CMOS process. The test results show that the analog gamma correction provides a 2.2 dB peak-signal-to-noise-ratio (PSNR) improved image quality, which is better than conventional digital gamma corrections.

The behavior of the {311} facet, which is observed in the selective epitaxial growth of Si(100), is investigated by ab initio calculations and by tight-binding calculations using the environment-dependent tight-binding Si potential. The most stable structure of the {311} facet in the long range order is found to be 3×2 interstitial structure based on the calculation of the surface energy. By comparing the maximum binding energies of adatoms on various structures of Si(311), it is found that the phase transition observed at ∼700°C is the transition from the 3×2 interstitial to the 3×1 interstitial structure and the phase transition is responsible for the behavior of the {311} facet. By tight-binding molecular dynamics simulation, it is also confirmed that the transition from the 3×2 interstitial to the 3×1 interstitial structure is induced by an adatom at high temperature and it corresponds to the transition from the 3×2 to the 3×1 phase of the Si(311) surface observed in experiment.

Surgical techniques have evolved tremendously over this past century. To maximize the efficacy and minimize the invasiveness of laparoscopic surgery, researchers have sought to implement wider application of robotics. Nevertheless, both optimism without sound evidence and fear of new technology obscure the appropriate uses of robotic surgery. In the present review, we attempted to provide a balanced perspective on the current state of robotic gastrectomy, outlining evidence and opportunities for the use thereof. Although evidence is limited, the use of robotics is feasible for gastric cancer surgery, and less than 10 cases of robotic surgery are needed to become proficient therein. Compared to the clinical impact of laparoscopy on gastric cancer surgery, the additional benefits of robotic surgery to patients seem to be limited. Despite additional costs and longer surgeries, robotic surgery reportedly does not offer surgical outcomes superior to those for laparoscopic surgery, according to a recent multicenter study. Meanwhile, however, our in-depth review of retrospective and prospective reports revealed that robots could expand the indications of minimally invasive gastrectomy for patients requiring total gastrectomy and D2 lymph node dissection. Moreover, we found that robotic gastrectomy is associated with a higher number of retrieved lymph nodes, less bleeding, fewer complications, and shorter hospital stay, compared to laparoscopic gastrectomy. Accordingly, new surgical approaches using advanced technologies, such as near infrared detectors, the Tilepro® multi-input display, dual consoles, and the Single-Site® system, are under investigation. In conclusion, measuring the additional benefits of robotic over laparoscopic surgery would be difficult and clinically insignificant. Thus, developing new surgical procedures that extend the benefits of conventional laparoscopic surgery to patients in whom minimally invasive surgery would not be possible is necessary to justify the greater use of robotic surgery.

Vertical NAND (VNAND) technology relies on polysilicon for channel material. Two intrinsic variation sources of the cell threshold voltage induced by polysilicon traps have been identified and simulated: Random Trap Fluctuation (RTF) and Random Telegraph Noise (RTN). We demonstrate that RTN is enhanced by the polysilicon material and an original model explains the asymmetric RTN distribution observed after endurance. This work enables the prediction of V T distribution for VNAND devices in MLC operation.

We have investigated thin film transistors (TFTs) with ultra-thin polycrystalline silicon (poly-Si) of 77 A – 185 A. The TFT charge transfer characteristics such as ON current and effective mobility are dominated not by the thickness itself but by the grain size of poly-Si channel. When the poly-Si channel thickness is decreased with the same grain size, the sub-threshold TFT characteristics are improved without degradation of ON current and reliability properties. These results give us appropriate criteria to establish an excellent poly-Si channel in vertical NAND flash memory.

Over the last few years, the demands for high-density and high-speed imaging have increased drastically. Since CMOS image sensors have the advantages of low power consumption and easy system integration, they have become dominant over CCDs in the consumer market [1–4]. A column-parallel ADC architecture is the most widely used ADC in CMOS image sensors for high-speed and low-power operation [2–6]. The column-parallel architecture can be classified as: successive-approximation register (SAR) [2], cyclic [3], single-slope (SS) [4], and delta-sigma (ΔΣ) [5,6] ADCs. Although SAR ADCs have been utilized for high-speed imaging, such as UDTV, they require a DAC in a column, whose area is unacceptably large for consumer electronics with a fine pixel pitch. Cyclic ADCs have also been reported in high-speed imaging, but they have high power consumption and high noise levels. Since SS ADCs provide relatively high resolution with minimum area, they have been widely used in CMOS image sensors. However, SS ADCs require very fast clock signals leading to high power consumption in the case of high-speed imaging. Although ΔΣ ADCs have been investigated for low-noise imaging, they have only been applied for low-speed imaging with large pixel pitch because of the complexity of ΔΣ modulators and following decimation filters.