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Background/Aims: Surgical resection, transplantation, and radiofrequency ablation (RFA) are generally accepted as amenable treatments for small hepatocellular carcinoma (HCC). Recently drug-eluting beads (DEB) which had several treatment advantages were introduced for transarterial chemoembolization (TACE). The aim of this study was to evaluate feasibility and safety of DEB-TACE compared with RFA for the treatment of single small HCC.Methods: In this pilot non-randomized trial, we assessed retrospective data of 40 patients who underwent DEB-TACE (n=21) or RFA (n=19) for single small (≤3 centimeter in greatest dimension) HCC. The primary outcomes were tumor response and time to recurrence. The secondary outcome was treatment-related complications.Results: Complete response rate to DEB-TACE and RFA after first follow-up assessment was 90.5% and 94.7%, respectively (P=1.000). During mean follow-up of 87.6 months (95% confidence interval: 74.4-102), 7 patients experienced local recurrence. The 6- and 12-month cumulative local recurrence rate was 5.0% and 21.8% in DEB-TACE vs. 11.1% and 17.0% in RFA group (P=0.877). A total 14 distant intrahepatic recurrences were developed and 12- and 24-month cumulative distant intrahepatic recurrence rate was 20.6% and 42.7% in DEBTACE vs. 17.2% and 36.3% in RFA group (P=0.844). Two patients experienced gangrenous cholecystitis after DEB-TACE requiring cholecystectomy as treatment-related adverse event.Conclusions: Tumor response and recurrence rate after single session of DEB-TACE or RFA were similar. DEB-TACE could be applied selectively in patients with a single small HCC if the other therapeutic modality is unfeasible.

The Smart Culture Lens developed in this study is an application developed by utilizing the visual element classification system of ceramic and AI technology. The user can analyze the visual elements of the ceramic photo taken with a smartphone and search for similar ceramics related to each visual element. For this development, as a first step, visual elements such as color, form, material, and pattern were defined as criteria for classifying ceramic appearance, and the visual element classification system of ceramics was organized. In the second step, 19,610 images of 7,346 ceramics were collected through museum visit photography and web, and a database was built by annotating these images with a visual element classification system. In the third step, representative object detection models, Faster R-CNN and Mask R-CNN were trained based on a ceramic classification system. Through those trained object detection models, visual elements and masks of the input image were recognized, and representative colors of the area were extracted using the k-means algorithm through the recognized masks. The performance of the trained object detection models (Average precision of Form / Material / Pattern 1st-level category = 0.87 / 0.89 / 0.72) shows that the amount of collected data and the established classification system are useful. Finally, by applying the above development results, a mobile application called ’Smart Culture Lens’ was developed, and the usefulness of this application was confirmed through a user experience test. This study combines AI technology into cultural heritage so that people can intuitively explore artifacts from a new perspective, which differs from traditional artifact exploring methods. All the detailed processes of this development will be a guide to how to apply AI technology to the cultural heritage.

In this article, a half-bridge (HB) integrated phase-shifted full-bridge (PSFB) converter with a new center-tapped clamp circuit is proposed to achieve high efficiency in electric vehicle battery charging systems. The proposed converter has the benefits of HB integrated PSFB converters, such as the extended zero-voltage-switching range and the reduced conduction loss on the primary side. In addition, by using a new center-tapped clamp circuit, which consists of two diodes and one capacitor, the proposed converter can solve the drawbacks of conventional PSFB converters, such as the substantial circulating current, the severe voltage stress and switching loss in the secondary full-bridge rectifier, and a large output inductor. With these improvements, the efficiency is fairly increased, and the volume of the output inductor is reduced. In order to validate the feasibility of the proposed converter, a 3.3-kW prototype was built and tested.

Background and Objectives: The purpose of this study was to investigate the effects of microcurrent stimulation on pain, shoulder function, and grip strength in patients with rotator cuff repair. Materials and Methods: This randomized single-blind controlled trial was conducted on inpatients of the rehabilitation department, and included 28 patients who underwent rotator cuff repair. Participants were randomly assigned to the experimental group (n = 14), treated with microcurrent stimulation, and the control group (n = 14), treated with false microcurrent stimulation. The microcurrent stimulation administered to the experimental group underwent general physical therapy and microcurrent stimulation three times a week for 4 weeks. Results: Changes in pain, range of motion in shoulder, simple shoulder test, and grip strength were assessed before and after the intervention. Both groups showed a significant decrease in pain and shoulder function (t = 27.412, 22.079, 19.079, and 18.561, p &lt, 0.001), and grip strength showed a significant increase (t = −8.251 and −9.946, 0.001). The experimental group that underwent microcurrent stimulation exhibited a significant effect on pain, shoulder function, and grip strength compared with the control group that underwent false microcurrent stimulation (t = −2.17, −2.22, and 2.213, p = 0.039, 0.035, and 0.036). Conclusions: This study confirmed that microcurrent stimulation is effective for the treatment of rotator cuff repair patients.

The purpose of this study was to investigate the effect of the combined isotonic technique (CIT) for proprioceptive neuromuscular facilitation and taping intervention on pain and grip strength in patients with lateral epicondylitis (LE). Twenty subjects with LE were treated 5 times a week for 4 weeks. Patients were randomized to an experimental group (n=10) with taping after CIT and a control group (n=10) with taping after stretching. A visual analogue scale (VAS) was used to measure changes in pain. A hand dynamometer was used to measure grip strength. A paired t-test was performed to compare differences after the intervention. We used an independent t-test to compare the differences between experimental and control groups. All statistical significance levels were set at α=0.05. Within-group changes in VAS and grip strength were significantly different in both the experimental and control groups (P

In this paper, a new LLC converter for series-connected, high-voltage LEDs is proposed. The proposed LLC converter consists of two stacked, single-ended rectifiers and one balancing capacitor, to compensate for the current deviation of two individual LED strings. The proposed LLC LED driver can use a diode with low voltage stress, even if the secondary LED is connected in series to have a high driving voltage. In addition, even if several series-connected LEDs are changed into two-stacked structures, the balancing capacitor can compensate for the current deviation of the two separated LEDs, as well as the difference in leakage inductance of the two stacked single-ended rectifiers. The balancing capacitor can be made equal to the voltage tolerance of the stacked, single-ended rectifier diodes. The proposed circuit can be easily extended to a series channel LED driver circuit, without increasing the voltage stress. To verify the characteristics and operation of the proposed LLC LED driver, a 260W high-power LED driver is implemented.

Traditional attempts at alleviating photoaging-associated facial pigmentation conditions such as melasma, mottled hyperpigmentation, and post-inflammatory hyperpigmentation have yielded disfiguring cosmetic results. Laser toning using a low-fluence Q-switched 1064-nm neodymium-doped yttrium aluminum garnet (Nd:YAG) laser has been more commonly applied to date. However, the treatment efficacy and safety of this approach have not been widely reported. This study therefore evaluated the efficacy and safety of picosecond 1064-nm Nd:YAG laser application for photoaging-associated facial pigmentation treatment in Korean subjects. Forty-seven Korean subjects with photoaging-associated facial pigmentation underwent picosecond 1064-nm laser application. The clinical improvement of 17 patients was assessed by objective measurements such as melanin and erythema indices. All subjects received six biweekly treatments with the laser in a three-pass fashion delivering approximately 2000 to 2500 shots using a zoom handpiece with a spot size of 7 mm, fluence ranging from 0.4 to 0.7 J/cm2, and a repetition rate of 10 Hz. Clinicians evaluated the improvement of pigmentation using the pigmentation area and severity index (PSI), and subjects reported their satisfaction level on a four-point scale. Statistical analyses were performed using the SPSS version 19.0 for Windows software program (IBM Corp., Armonk, NY, USA). Forty-seven subjects (45 females and two males) completed this study with a 12-week follow-up period. The average decrease in PSI value at 12 weeks after treatment was 6.85 ± 6.35 points (p

BACKGROUND The purpose of this study was to investigate the immediate effect of transcranial direct current stimulation (tDCS) on walking speed, functional strength of lower limbs, and balance in healthy older adults. Through this study, we intend to introduce a new method to improve the physical function of older adults. MATERIAL AND METHODS This was a randomized, controlled, double-blind study in which participants and evaluators were blinded. Among 57 healthy adults (aged 65 years or older), 31 underwent tDCS, while 26 received sham stimulation. For the pre-test, participants performed a 10-meter walk test, functional strength test of lower limbs, and static and dynamic balance tests. Next, the primary motor cortex area was subjected to tDCS for 20 min. Tests were repeated as post-tests. RESULTS There were significant differences in group-by-time interaction for 10-meter walk speed, functional strength of lower limbs, and static balance on the left side (P0.05). There was not a significant group-by-time interaction for dynamic and static balance on the right side (P0.05). There were significant differences in the main effect of time for 10-meter walk speed, functional strength of lower limbs, static balance on the right side, and dynamic balance (P0.05). CONCLUSIONS Results showed tDCS was effective in improving gait and functional strength of the lower limbs in older adults. We recommend tDCS as a safe and effective way to improve motor performance and increase physical function, including walking and functional strength of lower limbs, in older adults.

This paper proposes a soft-switched interleaved boost converter with minimal conduction loss increment and removed reverse-recovery problem. The soft-switching operation is enabled by a soft-switching cell composed of passive components in which an auxiliary coupled inductor and a dc-link capacitor are connected between the switch legs of the interleaved boost modules and output stage. Every MOSFET switch of the proposed boost converter operates with zero-voltage switching turn-on using the coupled inductor current. Consequently, the switching loss of the proposed interleaved boost converter is greatly reduced. In addition, the reduced circulating current in the auxiliary circuit minimizes the increment of the conduction loss. The proposed soft-switched interleaved boost converter operation is verified with 500-W experimental results.

Ultra-wideband (UWB) technology has emerged as a solution for the wireless interface between medical sensors and personal servers in future telemedicine systems. The WiMedia Alliance has specified a distributed medium access control protocol based on UWB for high-rate WPANs. In the cases of some applications, data traffic between the source device and destination device is transmitted via one or more intermediate links before it reaches the destination device. However, when all data frames do not transmit in the current DRP reservation block, a relay device cannot transmit the received data frame from the source device in the current DRP policy, until the next DRP duration reserved for forwarding to the destination device begins. This policy increases end-to-end latency between the source device and destination device significantly. Therefore, in this paper, we propose a novel reservation-based routing protocol to minimize the end-to-end delay between source and destination. The proposed routing protocol utilizes the number of medium access slots and hop-count to decide the optimal route between the source device and destination device. The simulation results show that the proposed protocol can enhance the throughput and delay performance and improve energy efficiency by minimizing the packet drop and collision.

Inhibition of the CXXC5–DVL interaction is a potential therapeutic strategy for height enhancement of children with growth retardation., Longitudinal bone growth ceases with growth plate senescence during puberty. However, the molecular mechanisms of this phenomenon are largely unexplored. Here, we examined Wnt-responsive genes before and after growth plate senescence and found that CXXC finger protein 5 (CXXC5), a negative regulator of the Wnt/β-catenin pathway, was gradually elevated with reduction of Wnt/β-catenin signaling during senescent changes of rodent growth plate. Cxxc5−/− mice demonstrated delayed growth plate senescence and tibial elongation. As CXXC5 functions by interacting with dishevelled (DVL), we sought to identify small molecules capable of disrupting this interaction. In vitro screening assay monitoring CXXC5–DVL interaction revealed that several indirubin analogs were effective antagonists of this interaction. A functionally improved indirubin derivative, KY19382, elongated tibial length through delayed senescence and further activation of the growth plate in adolescent mice. Collectively, our findings reveal an important role for CXXC5 as a suppressor of longitudinal bone growth involving growth plate activity.

The majority of mobile apps use credentials to provide an automatic login function. Credentials are security tokens based on a user's ID and password information. They are created for initial authentication, and this credential authentication then replaces user verification. However, because the credential management of most Android apps is currently very insecure, the duplication and use of another user's credentials would allow an attacker to view personal information stored on the server. Therefore, in this paper, we analyze the vulnerability of some major mobile SNS apps to credential duplication that would enable access to personal information. To address the identified weaknesses, we propose a secure credential management scheme. The proposed scheme first differentiates the credential from the smart device using an external device. Using a security mechanism, the credential is then linked with the smart device. This ensures that the credential will be verified by the special smart device. Furthermore, based on experimental results using a prototype security mechanism, the proposed scheme is shown to be a very useful solution because of its minimal additional overhead.

Since the World Trade Center and Pentagon attacks in 2001, terror bombings, military attacks and man-made disasters have frequently induced impacts, explosions and fire on civil infrastructure. However, research into the structural behaviour of major prestressed concrete (PSC) infrastructure (e.g. bridges, tunnels, prestressed concrete containment vessels (PCCVs) and liquefied natural gas (LNG) storage tanks) under extreme loading is limited due to the difficulties involved in conducting studies on instantaneous extreme loading scenarios. In particular, research into possible secondary fire scenarios on concrete structures after a bomb explosion or accidental collision has not been performed, while most previous research is related to extreme isolated loading scenarios on structures. Due to a great deal of public concern and anxiety over potential collision accidents on major infrastructure, a study on PSC structural behaviour from an impact-induced fire scenario was undertaken. Bi-directional PSC panels of size 1400 × 1000 × 300 mm subjected to a 430 kN prestressing force using unbonded prestressing thread bars were tested for an impact–fire loading scenario. More specifically, using a drop weight test facility in Korea, tests were performed using a 14 kN impactor with drop heights of 10 m and 3·5 m to apply impact loading to the PSC panels. RABT fire loading was then applied to the impact-damaged PSC panels. After the impact–fire test, a three-point line loading test was performed on various undamaged and damaged reinforced concrete and PSC panels to evaluate and compare their residual bending strengths. The results obtained from the study can be used as basic data for the protective design of PSC panel structures such as PCCVs and LNG tanks for real impact accident scenarios.

Wireless power transfer technologies typically include inductive coupling, magnetic resonance, and capacitive coupling methods. Among these methods, capacitive coupling wireless power transfer (CCWPT) has been studied to overcome the drawbacks of other approaches. CCWPT has many advantages such as having a simple structure, low standing power loss, reduced electromagnetic interference (EMI) and the ability to transfer power through metal barriers. In this paper, the CCWPT system with 6.78MHz class D inverter is proposed and analyzed. The proposed system consists of a 6.78MHz class D inverter with a LC low pass filter, capacitor between a transmitter and a receiver, and impedance transformers. The system is verified with a prototype for charging mobile devices.

High-efficiency dual half-bridge converters are analyzed to achieve a zero voltage switching (ZVS) with a wide load range for a large sized plasma display panel (PDP) sustaining power module. The circuit consists of the dual half-bridge configuration in a primary side, two voltage doublers rectifiers in a secondary side, and the ZVS tank. The ZVS operation of the primary switches can be obtained with the ZVS tank irrespective of a load condition. In addition, although the proposed converter does not have the output inductive filter, a root mean square (RMS) current stress of the output capacitor can be reduced by the complementary operation. An experimental prototype of 900 W power converter is constructed and tested to verify the features of the proposed converter. As a result, the proposed sustaining power circuit can achieve more than 92% of high efficiency at 10% load condition and the ZVS operation is achieved at the light load condition.

Although the number of terror-and explosion-related incidents associated with military and terrorist activities is increasing globally, the existing design procedure for civil infrastructures does not consider a protective design for extreme loading scenarios such as blast, impact, and fire loading. Major infrastructure, for example bridges, tunnels, prestressed concrete containment vessels (PCCVs), and liquefied natural gas (LNG) storage tanks are often constructed using prestressed concrete, because it enhances the structural capacity. Concrete is often used as a construction material because of its low thermal conductivity, which makes it a good fire resistant material. However, the fire-resistant behavior of the high-strength concrete (HSC) and prestressing (PS) tendons used in prestressed concrete (PSC) is different than that of ordinary reinforced concrete (RC). Also, there has been limited research comparing PSC to RC under extreme loading conditions. This study presents experimental testing of unbonded bi-directionally prestressed concrete panels with dimensions 1000×1400×300 mm 3 that were tested under RABT fire loading to simulate a jet aircraft crash-fire accident. A prestressing force of 430 kN was applied to the PSC specimens using unbonded threaded bars. After a RABT fire test, residual flexural strength tests were performed on the fire-damaged PSC and on RC specimens for comparison. Results of the RABT fire and residual flexural strength tests indicated that the fire-damaged PSC specimens showed severe thermal spalling damage induced by PS relaxation and deterioration of strength/stiffness, respectively. These study results can be used as basic research data for future research in numerical simulation of fire and the design of PSC structures under the fire scenario.

This paper presents a ZVT(zero-voltage-transition) interleaved synchronous buck converter with passive soft-switching cell to achieve ZVS(zero-voltage-switching) of MOSFET switches. The proposed interleaved buck converter is composed of two synchronous buck converter modules and passive soft-switching cell. The passive soft-switching cell consists of coupled-inductor and DC-link capacitor. All switches operate with ZVS by the current of auxiliary coupled-inductor. Comparing the conventional interleaved buck converter, the proposed interleaved buck converter reduces the switching loss and increases the efficiency by using only passive components. In this paper, mode analysis and design consideration is described in detail for operating the ZVS. The proposed ZVT interleaved synchronous buck converter is verified with experimental results.

3) Defense Systems Test Center-3, Agency for Defense Development, Pocheon 486-859, Korea ABSTRACT In recent years, frequent terror or military attacks by explosion or impact accidents have occurred. Examplary case of these attacks were World Trade Center collapse and US Department of Defense Pentagon attack on Sept. 11 of 2001. These attacks of the civil infrastructure have induced numerous casualties and property damage, which raised public concerns and anxiety of potential terrorist attacks. However, a existing design procedure for civil infrastructures do not consider a protective design for extreme loading scenario. Also, the extreme loading researches of prestressed concrete (PSC) member, which widely used for nuclear containment vessel, gas tank, bridges, and tunnel, are insufficient due to experimental limitations of loading characteristics. To protect concrete structures against extreme loading such as explosion and impact with high strain rate, understanding of the effect, characteristic, and propagation mechanism of extreme loadings on structures is needed. Therefore, in this paper, to evaluate the impact resistance capacity and its protective performance of bi-directional unbonded prestressed concrete member, impact tests were carried out on 1400 mm×1000 mm×300 mm for reinforced concrete (RC), prestressed concrete without rebar (PS), prestressed concrete with rebar (PSR, general PSC) specimens. According to test site conditions, impact tests were performed with 14 kN impactor with drop height of 10 m, 5 m, 4 m for preliminary tests and 3.5 m for main tests. Also, in this study, the procedure, layout, and measurement system of impact tests were established. The impact resistance capacity was measured using crack patterns, damage rates, measuring value such as displacement, acceleration, and residual structural strength. The results can be used as basic research references for related research areas, which include protective design and impact numerical simulation under impact loading.

A Capacitive coupling wireless power transfer (WPT) circuit with a compensated L is proposed. Two pairs of small area metal electrodes are used to produce two coupling capacitors and a resonant inductor is employed for the capacitive coupling wireless power transfer. By adding one parallel inductor to the series resonant circuit, an output voltage gain greater than 1 can be achieved. In addition, zero voltage switching (ZVS), zero current switching (ZCS), and higher output voltage can be obtained using the compensated inductor even at high frequency operation. A 6.3W Capacitive coupling WPT system is implemented with an approximately 700pF coupling capacitance by two 108cm2 copper plates and 6.78MHz operation for charging a small power electric device. The experimental results confirm the ZVS and ZCS operation, higher efficiency, and larger output voltage.

A highly efficient sustaining driver is proposed for plasma display panels (PDPs). When the PDP is charged and discharged, the proposed sustaining driver employs an address voltage source used in an addressing period. A voltage source is used for fully charging the panel to the sustaining voltage, and an initial inductor current helps the panel discharge to 0 V. The resonance between the panel and an inductor is made by shifting the voltage and current bias level when charging and discharging the panel. As a result, the proposed circuit can reduce power consumption, switching loss, heat dissipation, and production cost. Experimental results of a 42-inch PDP are provided to verify the operation and features of the proposed circuit.

Plasma display panel (PDP) televisions are facing to have a new chance to receive attention along with a boom in 3-D software and contents because PDP can provide the comfortable and realistic 3-D images. The PDP has three driving circuit boards such as X, Y and addressing boards. Cost effective driving waveform has already been reported to decrease the number of driving circuit board. Half bridge based sustaining driver can remove a sustaining driver in the X board. However, the biasing circuit in the X driving boards cannot be reduced because there are some drawbacks such as unstable gas discharge condition and unreliability of an address driver IC. In this paper, the half bridge based sustaining driver is considered and a simple address driver is proposed to remove one driving board, X driving board. The stable gas discharge condition, reliability of the address driver IC and the low cost can be obtained by the proposed circuit.

Commercial home appliances using remotely controlled systems consume electric power while in standby mode to prepare for receiving a remote turn-on signal. The proposed power system can significantly reduce standby power consumption without increasing cost. Furthermore, since a Electronic Double Layer Capacitor (EDLC) is used as an auxiliary power storage element, the life cycle is longer and system reliability can be better than with existing approaches. When the energy of the EDLC is not sufficient for turning on the appliance, the power system charges the EDLC without affecting the main system. The proposed power system is verified with a commercial LCD TV and a 3.93mW standby consumption is obtained. This standby consumption can be regarded as zero standby equipment according to the IEC-62031 standard.

Recently, major infrastructure such as bridges, tunnels, PCCVs (Prestressed Concrete Containment Vessel), and gas tanks are Prestressed Concrete (PSC) structure types, which improve their safety by using confining effect from prestressing. Gen- erally, concrete is known to be an outstanding fire resistant construction material. Because of this reason, researches related to extreme fire loaded PSC member behaviors are not often conducted even though PSC behavior under extreme fire loading is sig- nificantly different than that of ordinary reinforced concrete (RC) behavior. Therefore, in this study, RABT fire loading tests were performed on bi-directionally prestressed concrete panels with 1000×1400×300 mm dimensions. The prestressed specimens were applied with 430 kN prestressing (PS) force using unbonded PS thread bars. Also, residual strength structural tests of fire tested PSC and ordinary RC structures were performed for comparison. The study results showed that PSC behavior under fire loading is significantly different than that of RC behavior.

This paper presents a new parallel output LLC DC/DC converter for electric vehicle. There are a high voltage battery for the power train of the vehicle and a low voltage battery for the vehicle electric system in the electric vehicle. The new LLC converter with the input voltage compensation is proposed for the high voltage input and the low voltage output DC/DC converter to charge the low voltage battery from the high voltage battery. The proposed circuit has two LLC converters with the series input voltage from the battery for the power train and the parallel output low battery voltage for the vehicle electric system. Also, the input series voltage compensation capacitor is used for balancing the input current in the two LLC converters. The proposed converter has an equal electric stress of the semiconductor parts and the reactive components, high efficiency and good heat dissipation. Features of the proposed circuit are verified with a simulation result.

Wireless power transfer (WPT) technologies are magnetic and capacitive coupling methods, typically. The capacitive coupling WPT has many advantages such as simple structure, low electromagnetic interference and transferring with metal barrier. However, it is hard to reduce the impedance of coupling capacitor for sufficient received output voltage in the capacitive coupling WPT. Therefore, in this paper, 6.78MHz high frequency operation and glass dielectric layers can make an impedance of the coupling capacitance small and it is possible to transfer power easily. In addition, less switching loss can be obtained for high efficiency and low electromagnetic interference (EMI) noise with the LLC resonant tank. It results in high efficiency and sufficient output power. Features of the proposed converter are verified with a 4.2W prototype for charging a mobile device.

This paper proposes a soft-switching interleaved boost converter using an auxiliary coupled inductor to achieve zero voltage switching (ZVS) of MOSFET switches and zero current switching (ZCS) of the body diodes of the switches. The proposed interleaved boost converter is comprised of two synchronous boost converter modules and the auxiliary coupled inductor and DC-link capacitor connected between main switches of each boost converter module and output stage. All MOSFET switches of the proposed boost converter operate with ZVS turn-on by using the current of the coupled inductor. Furthermore, the current of the coupled inductor enables the ZCS turn-off of the MOSFET body-diodes to eliminate their reverse-recovery process. Consequently, the switching loss of the proposed interleaved boost converter can be greatly reduced. The operation of the proposed soft-switching interleaved boost converter is verified with experimental results.

Wireless power transfer (WPT) technologies are typically inductive coupling, magnetic resonance, and electric field methods. Among them, electric field WPT has been studied to overcome the drawbacks of other approaches. The electric field WPT has many advantages, such as a simple structure, low standing power loss, reduced EMI (Electromagnetic Interference), and the ability to transfer power through metal barriers. Therefore, this paper proposes the electric field WPT system at 6.78MHz. The proposed WPT system was composed of a 6.78MHz class D inverter with a LC low pass filter, a capacitor between the transmitter and the receiver, and an impedance transformer. The system was verified using a 5.5W prototype for charging mobile devices.

Recent advances in nanotechnology research have been applied to improve the durability, serviceability, and safety of ultra-high performance concrete (UHPC). Furthermore, improvements in the compressive strength of concrete have allowed concrete structural member size and self-weight to be significantly reduced, which has in turn resulted in cost reduction and structural aesthetic enhancement. Among many UHPCs currently available on the market, the most representative ones are ultra-high strength concrete (UHSC) and reactive powder concrete (RPC). Even though UHSC and RPC have compressive strengths of over 100 MPa, their safety has been questioned due to possible ultra-brittle failure behavior and unfavorable cost-to-performance efficiency. The blast-resistant capacities of UHSC and RPC were experimentally evaluated to determine the possibility of using UHSC and RPC in concrete structures susceptible to terrorist attacks or accidental impacts. Slump flow, compressive strength, split tensile strength, elastic modulus, and flexure strength tests were carried out. In addition, ANFO blast tests were performed on reinforced UHSC and RPC panels. Incidental and reflected pressures, as well as maximum and residual displacements and the strains of rebar and concrete were measured. Blast damage and failure modes of the reinforced panel specimens were recorded. Our results showed that UHSC and RPC have better blast explosion resistance than normal strength concrete. The study results are discussed in detail.

A new address energy recovery (AER) circuit of ac plasma display panel (PDP) (AC-PDP) is proposed. The proposed circuit converter shows the load-adaptive characteristics, which can minimize the unnecessary power consumption of AER circuit according to the displayed image. Moreover, the proposed circuit, employing a p-channel MOSFET which does not require a complex floating gate driver, can be implemented with low cost. Based on the estimated equivalent capacitance of PDP, the proposed AER circuit is designed to implement the prototype for 50-in high-definition PDP. The load-adaptive AER operation and the address-power-saving characteristic are verified experimentally. Therefore, the proposed circuit is very suitable for the low-cost AER circuit of AC-PDP.

Isomeric pyridyl-substituted diaminotriazines 2a–c and elongated analogue 3 are designed to adopt flattened structures with features that favor adsorption on surfaces and participation in multiple intermolecular interactions. In particular, pyridyl and diaminotriazinyl groups have strong affinities for graphite, and both form coplanar hydrogen-bonded adducts with alkanecarboxylic acids according to reliable motifs. Together, these properties predispose compounds 2a–c and 3 to be coadsorbed with alkanecarboxylic acids on graphite and to cocrystallize as structures built from hydrogen-bonded sheets. Comparison of the 2D structures of the ordered adlayers (as determined by scanning tunneling microscopy) with the 3D structures of the cocrystals (as determined by X-ray diffraction) showed striking homology, typically with quantitatively similar structural parameters. Together, these results illustrate how a series of related compounds can be engineered to form ordered adlayers and crystalline solids with close...

Recently, the probability of collision accident between vehicles or vessels and infrastructures are increasing at alarming rate. Particularly, collision impact load can be detrimental to sub-structures such as piers and columns. The damaged pier from an impact load of a vehicle or a vessel can lead to member damages, which make the member more vulnerable to impact load due to other accidents which. In extreme case, may cause structural collapse. Therefore, in this study, the vehicle impact load on concrete compression member was considered to assess the quantitative design resistance capacity to improve, the existing design method and to setup the new damage assessment method. The case study was carried out using the LS-DYNA, an explicit finite element analysis program. The parameters for the case study were cross-section variation of pier, impact load angle, permanent axial load and axial load ratio, concrete strength, longitudinal and lateral rebar ratios, and slenderness ratio. Using the analysis results, the performance based resistance capacity evaluation method for impact load using satisfaction curve was developed using Bayesian probabilistic method, which can be applied to reinforced concrete column design for impact loads.

A new high-efficient multilevel half-bridge converter is proposed in this paper. The proposed converter regulates the output voltage by adjusting applied voltage on the main transformer with an auxiliary circuit while main switches are operated at both fixed duty ratio and switching frequency. Therefore, no magnetizing dc offset current exists on the main transformer and all switches can be operated with zero voltage switching condition. Furthermore, multilevel voltage shown at the output filter reduces the output inductance significantly. To verify these features of the proposed circuit, operational principle and experimental results will be presented with the 700 W prototype.

Most PET bottles used as beverage containers become waste after their usage, causing environmental problems. To address this issue, a method to recycle wasted PET bottles is presented, in which short fibers made from recycled PET are used within structural concrete. To verify the performance capacity of recycled PET fiber reinforced concrete, it was compared with that of polypropylene (PP) fiber reinforced concrete for fiber volume fractions of 0.5%, 0.75%, and 1.0%. Appropriate tests were performed to measure material properties such as compressive strength, elastic modulus, and restrained drying shrinkage strain. Flexural tests were performed to measure the strength and ductility capacities of reinforced concrete (RC) members cast with recycled PET fiber reinforced concrete. The results show that compressive strength and elastic modulus both decreased as fiber volume fraction increased. Cracking due to drying shrinkage was delayed in the PET fiber reinforced concrete specimens, compared to such cracking in non-reinforced specimens without fiber reinforcement (NF), which indicates crack controlling and bridging characteristics of the recycled PET fibers. Regarding structural member performance, ultimate strength and relative ductility of PET fiber reinforced RC beams are significantly larger than those of companion specimens without fiber reinforcement.

An improved dual-path energy recovery circuit (ERC) using a current source and a voltage source for plasma display panel (PDP) is proposed. The proposed ERC uses the voltage source to charge a panel and the current source to discharge the panel. Thus, the proposed circuit can make the panel charge to a sustaining voltage VS and fully discharge to 0 V, and it is possible to achieve zero-voltage switching for all switches in an H-bridge inverter and zero-current switching for all switches in the ERC. Moreover, it has less conduction and switching loss in ERC devices by the dual energy recovery paths for charging and discharging the panel. Furthermore, it has the features of canceling the gas discharge current, high performance, and the low-cost ERC components. The operation principle and features of the proposed ERC are presented in detail and verified with 42-in standard definition (SD) PDP.

An LLC series-resonant converter has many unique characteristics and improvements over pulsewidth-modulation topologies. However, many output capacitors are needed in parallel to satisfy an output voltage ripple and a rated ripple current of the capacitors. This paper deals with a novel two-phase interleaved LLC resonant converter using a phase of the resonant capacitor. The proposed converter satisfies low output-voltage ripple requirement and meets the rated ripple of output capacitor's current with few output capacitors. The operation and features are considered in detail, and a prototype with a 12-V-100-A output is investigated.

A comparative study of a single sustaining driver (SSD) with single- and dual-energy recovery paths for plasma display panels (PDPs) is shown in this paper. The cost of PDPs is still very high and half of the cost includes the driving circuit. Therefore, it is important to have cost-effective driving waveform and the SSD to reduce the cost and size of the driving circuit. The SSD has fewer switching devices and reactive components and can be developed with single- and dual-path energy recovery circuits for charging and discharging PDPs. We shall evaluate the performance of these circuits in this paper. Since the dual-path energy recovery circuit has low power consumption, low surge current, and high performance. We shall verify these results using a 42-in high-definition panel.

A new dual sustaining driver using two different energy recovery circuits (ERCs) for large-sized plasma display panels (PDPs) is proposed. The proposed sustaining driver has two H-bridge inverters to be used in splitting a panel into two. Two ERCs are employed to compensate energy for charging or discharging the panel. When PDPs with the two divided panels are driven by the proposed driver, there are good uniformity in gas discharge and reduction of power consumption by the two different ERCs used in charging and discharging the panel. As results, the proposed sustaining driver has low conduction loss, diminished switching loss of all main power switches, and decrease of reactive power consumption for recovering energy. Moreover, production cost can be reduced because of the simplified ERC for discharging the panel and no additional driving circuits. To verify the operation of the proposed circuit, experimental results will be shown by using a 42-in panel.

A simple and highly efficient energy recovery circuit (ERC) for a plasma display panel (PDP) is proposed. The main concept of the proposed circuit is the use of the current source type to charge and discharge the panel. As a result, all H-bridge switches can achieve zero voltage switching and every auxiliary switch can also do zero current switching. Moreover, since the inductor current can compensate for the large gas-discharge current, current stress in the main H-bridge switches can be reduced. Although the current source type is used to recover energy in the PDP, there is also very low freewheeling current. This means that the proposed ERC has higher efficiency, a simpler structure, less mass, less cost, and lower electromagnetic interference than those of many prior circuits.

Integrated studies using scanning tunneling microscopy and X-ray crystallography have established that 4,5,9,10-tetrahydropyrene-2,7-dicarboxylic acid and pyrene-2,7-dicarboxylic acid crystallize in 2D and 3D with striking homology. Different behavior is shown by related biphenyls that lack the planarizing conformational constraints of the pyrenyl core and the directing effects of intermolecular hydrogen bonding. The results of these studies show that molecules specifically designed to engage in multiple strong directional interadsorbate interactions are promising tools for imposing particular nanopatterns on surfaces and for revealing subtle aspects of crystallization.

The present study demonstrates broadband UV-B-induced damage of cultured human retinal pigment epithelial cells as an effort to develop an in vitro model that can be used, along with in vivo research and other in vitro efforts, to evaluate the need for retinal UV protection in humans after cataract removal. The human retinal pigment epithelial cell line, ARPE-19, was cultured in two groups: control and treated. Treated cells were irradiated with three broadband UVB radiations at energy levels of 0.05, 0.1 and 0.2 J/cm 2 . After irradiation, cells were incubated for 48 h while cellular viability, morphology, and phagocytotic activity were analyzed using the Alamar blue assay, confocal microscopy, and fluorescent microspheres. Confocal analysis concentrated on the study of the cell nuclei and mitochondria. The Alamar blue assay of UV-B-exposed cells showed dose and time-dependent decreases in cellular viability in comparison to control cells. Loss of cell viability was measured at the two higher energy levels (0.2 and 0.1 J/cm 2 ), but the cell group exposed to 0.05 J/cm 2 showed no significant viability change at 1-h time point. Morphological evaluation also showed dose and time-dependent degradation of mitochondria and nucleic acids. Cells exposed with 0.05 J/cm 2 UVB did not show significant degradation of mitochondria and nucleic acids during the entire culture period. Phagocytotic activity assay data for UVB-exposed cells showed dose-dependent decreases in phagocytotic activity in comparison with the control cells. The control cells have significantly greater capacities for uptake than the 0.1 and 0.2 J/cm 2 UV-B-exposed cells, while the 0.05 J/cm 2 UV-B-exposed cell group showed no significant difference from the control cell group. The findings suggest that UVB radiation-induced cultured RPE cell damage can be evaluated by assays that probe cellular viability, morphological change, and phagocytotic activity, and that these assay methods together provide a valuable in vitro model for ultraviolet radiation-induced retinal toxicology research.

Mitochondria play an important role in many cellular and physiologic functions. Mitochondria are dynamic organelles, and their fusion and fission regulate cellular signaling, development, and mitochondrial homeostasis. The most common complaint of human immunodeficiency virus (HIV)-sensory neuropathy is pain on the soles in patients with HIV, but the exact molecular mechanisms of HIV neuropathic pain are not clear. In the present study, we investigated the role of mitochondrial dynamin-related protein 1 (Drp1, a GTPase that mediates mitochondrial fission) in the perineural HIV coat glycoprotein gp120-induced neuropathic pain state.Neuropathic pain was induced by the application of recombinant HIV-1 envelope protein gp120 into the sciatic nerve. Mechanical threshold was tested using von Frey filaments. The mechanical threshold response was assessed over time using the area under curves. Intrathecal administration of antisense oligodeoxynucleotide (ODN) against Drp1, mitochondrial division inhibitor-1 (mdivi-1), or phenyl-N-tert-butylnitrone (a reactive oxygen species scavenger) was given. The expression of spinal Drp1 was examined using western blots. The expression of mitochondrial superoxide in the spinal dorsal horn was examined using MitoSox imaging.Intrathecal administration of either antisense ODN against Drp1 or mdivi-1 decreased mechanical allodynia (a sensation of pain evoked by nonpainful stimuli) in the gp120 model. Intrathecal ODN or mdivi-1 did not change basic mechanical threshold in sham surgery rats. Intrathecal Drp1 antisense ODN decreased the spinal expression of increased Drp1 protein induced by peripheral gp120 application. Intrathecal phenyl-N-tert-butylnitrone reduced mechanical allodynia. Furthermore, both intrathecal Drp1 antisense ODN and mdivi-1 reversed the upregulation of mitochondrial superoxide in the spinal dorsal horn in the gp120 neuropathic pain state.These data suggest that mitochondrial division plays a substantial role in the HIV gp120-related neuropathic pain state through mitochondrial reactive oxygen species and provides evidence for a novel approach to treating chronic pain in patients with HIV.

As the number of smart device users has increased, PC-based smart work environments of businesses and public institutions have opted to adopt mobile offices to support their employees. However, with the trend of BYOD (Bring Your Own Device), security problems such as the leaking of confidential information of businesses and important contents have also developed. Thus, the paper proposes utilization of Portable MDM as the solution to such security threats.

To log in to a mobile social network service (SNS) server, users must enter their ID and password to get through the authentication process. At that time, if the user sets up the automatic login option on the app, a sort of security token is created on the server based on the user’s ID and password. This security token is called a credential. Because such credentials are convenient for users, they are utilized by most mobile SNS apps. However, the current state of credential management for the majority of Android SNS apps is very weak. This paper demonstrates the possibility of a credential cloning attack. Such attacks occur when an attacker extracts the credential from the victim’s smart device and inserts it into their own smart device. Then, without knowing the victim’s ID and password, the attacker can access the victim’s account. This type of attack gives access to various pieces of personal information without authorization. Thus, in this paper, we analyze the vulnerabilities of the main Android-based SNS apps to credential cloning attacks, and examine the potential leakage of personal information that may result. We then introduce effective countermeasures to resolve these problems.

Mitochondria provide energy generated by oxidative phosphorylation and at the same time play a central role in apoptosis and aging. As a byproduct of respiration, the electron transport chain is known to be the major intracellular site for the generation of reactive oxygen species (ROS). Exposure to solar and occupational ultraviolet (UV) radiation, and thus production of ROS and subsequent cell death, has been implicated in a large spectrum of skin and ocular pathologies, including cataract. Retinal pigment epithelial cell apoptosis generates photoreceptor dysfunction and ultimately visual impairment. The purpose of this article was to characterize in vitro changes following oxidative stress with UV-B radiation in (a) ocular lens optics and cellular function in terms of mitochondrial dynamics of bovine lens epithelium and superficial cortical fiber cells and (b) human retinal pigment epithelial (ARPE-19) cells. Cultured bovine lenses and confluent cultures of ARPE-19 cells were irradiated with broadband UV-B radiation at energy levels of 0.5 and 1.0 J/cm(2). Lens optical function (spherical aberration) was monitored daily up to 14 days using an automated laser scanning system that was developed at the University of Waterloo. This system consists of a single collimated scanning helium-neon laser source that projects a thin (0.05 mm) laser beam onto a plain mirror mounted at 45 degrees on a carriage assembly. This mirror reflects the laser beam directly up through the scanner table surface and through the lens under examination. A digital camera captures the actual position and slope of the laser beam at each step. When all steps have been made, the captured data for each step position is used to calculate the back vertex distance for each position and the difference in that measurement between beams. To investigate mitochondrial movement, the mitochondria-specific fluorescent dye Rhodamine 123 was used. Time series were acquired with a Zeiss 510 (configuration Meta 18) confocal laser scanning microscope equipped with an inverted Axiovert 200 M microscope and 40-x water-immersion C-Apochromat objective (NA 1.2). The optical analysis showed energy level-dependent increases in back vertex distance variability (loss of sharp focus) from 0.39 +/- 0.04 mm (control, n = 11) to 1.63 +/- 0.33 mm (1.0 J/cm(2), n = 10) and 0.63 +/- 0.13 mm (0.5 J/cm(2), n = 9). Confocal laser scanning microscopy analysis of both bovine lenses and ARPE-19 cells showed that following treatment at 0.5 J/cm(2) the mitochondria stopped moving immediately whereas at 1.0 J/cm(2) not only did the mitochondria stop moving, but fragmentation and swelling was seen. Untreated control tissue exhibited up to 15 microm/min of movement of the mitochondria. This could represent normal morphological change, presumably allowing energy transmission across the cell from regions of low to regions of high ATP demand. Lack of mitochondrial movement, fragmentation, and swelling of mitochondria may represent early morphological changes following oxidative stress that may lead to activation of caspase-mediated apoptotic pathways.

Retinoblastoma is a pediatric retinal tumor caused by mutational inactivation of the tumor suppressor pRb. Additional genetic changes, as yet unidentified, are believed to be required for tumor initiation. Mutations in the Wnt signaling pathway have been implicated in the pathogenesis of many cancers. Multiple Wnt pathway genes are expressed in the retina and the pRb and Wnt pathways interact biochemically, raising the possibility that alterations in the Wnt pathway contribute to retinoblastoma. Our studies showed that Wnt signaling activation significantly decreased the viability of retinoblastoma cell lines by inducing cell cycle arrest, which was associated with upregulated p53. Furthermore, immunolocalization of the Wnt signaling mediator β-catenin in human and mouse retinoblastoma tissue indicated that canonical Wnt signaling is suppressed in tumors in vivo. These studies are consistent with the Wnt pathway acting as a tumor suppressor in retinoblastoma and suggest that loss of Wnt signaling is tumorigenic in the retina.

We have successfully developed an "all-laser" processing for the localized growth of suspended single-wall carbon nanotubes (SWCNTs) on prepatterned SiO/sub 2//Si substrates. Our "all-laser" process stands out by its exclusive use of the same KrF excimer laser, first, to deposit the embedded-catalyst electrodes with a controllable architecture and, second, to grow SWCNTs through the pulsed laser ablation of a pure graphite target. Under the optimal growth conditions, the suspended SWCNTs are shown to bridge laterally adjacent electrodes separated by a gap of /spl sim/2 /spl mu/m. These SWCNTs (having diameters in the 1.25-1.64-nm range) generally tend to auto-assemble into bundles of /spl sim/5--15 nm in diameter. The "all-laser" process here developed offers the advantage of a direct integration of the SWCNTs into field-effect-transistor-like devices with no postprocessing, thereby permitting the investigation of their electrical transport properties. Thus, the suspended SWCNT bundles are shown to behave collectively as an ambipolar transistor with ON/OFF switching ratios as high as /spl sim/10/sup 4/.