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Much attention has been given to the sun as a source of alternative energy for conserving energy. Recently, solar energy technologies have been linked with IT to reduce the energy consumed in buildings, with proven effectiveness. In this study, we investigate the effectiveness of a light shelf with user-awareness and dimming control features. We assess the efficiency of a light shelf in saving lighting energy by examining each component of the light shelf. A testbed is used to verify the lighting energy-saving effect of this light shelf. In order to determine the energy consumption in different situations, we examine three cases. Case 1 features a light shelf that is user-unaware but with lighting On/Off control. Case 2 features a light shelf that is user-aware with lighting On/Off control. Case 3 features a light shelf that is user-aware with dimming control. Users were classified by target illumination levels according to illumination standards: A (600 lx), B (400 lx), and C (300 lx). The appropriate standards and lighting energy consumption levels for each Case were found through this study, and the lighting energy saving performance of the light shelf that is user-aware and applies light dimming technology proposed here was verified.

Computational fluid dynamics (CFD) is being used in various research fields on the building environment. Target space of the CFD model is divided into a finite number of grids for numerical analysis. Therefore, an optimal grid design is required to obtain accurate results. The grid independence test is generally performed to design an optimal grid. However, given that there is no standardized procedure for gird independence test, most depend on the researcher’s experience and knowledge. In the conventional method, the subjective judgment of the researcher affected the selection of the grid conditions and the criteria for the optimal grid. It can lead to a decrease in the reliability of the simulation results by poor grid design. This study proposed a grid independence test method that applies the grid resolution to improve the conventional method. The grid resolution was calculated by applying the characteristic length. CV(RMSE) and R2 were applied as the criteria for optimal grid. A case study was conducted to evaluate the adequacy of the proposed method. As the characteristic length increased, the optimal grid resolution increased. In particular, for a characteristic length of 0.7 or more, the optimal grid resolution was evaluated as 24. The grid convergence index (GCI) was calculated to verify the suitability of the proposed method. As a result, all of the optimal grid resolution derived from the proposed method was evaluated as the optimal condition.

A window set is defined as a window where the frame and the glass are combined and is used at the part that comes into contact with the air. As the performance evaluation of window sets has gained significance, the need for software that can simulate window set performance has also increased accordingly. However, the simulation of window sets is not carried out efficiently due to the difficulty in the window set modeling. Meanwhile, the design of building information modeling has recently proliferated so that the window set BIM library is distributed online. If such a window set BIM library is utilized in the window set simulation, it is expected that the productivity issue that occurs in the simulation process could be improved. Therefore, this study proposes a method to automatically convert the information required in the simulation of the window set heat transfer coefficient from the BIM. In order to achieve the purpose of this study, the following procedure is carried out. First, the framework for converting the information required in the simulation of the window set heat transfer coefficient from the BIM is suggested. Second, the method to extract and convert BIM data based on the suggested framework is proposed. Lastly, the BIM data conversion program is developed, and its performance is validated by applying the window set BIM case. The case study result showed that the information converted and entered from the window set data BIM conversion program coincided with the information entered in the window set BIM. It is expected that the result of this study will increase the productivity of window set simulations, which will lead to the increased use of certification through these simulations.

The effects of crystal orientation on the optical gain characteristics of blue AlInGaN/InGaN quantum-well (QW) structures with a reduced internal field were investigated by using the non-Markovian model with many-body effects. The AlInGaN/InGaN system has a larger matrix element than the conventional InGaN/GaN system because the former has a smaller internal field than the latter for relatively small crystal angles. As a result, for QW structures with a relatively small crystal angle (θ = 30°), the AlInGaN/InGaN system is shown to have a much larger optical gain than the conventional InGaN/GaN system. On the other hand, in the case of QW structures with a large crystal angle (θ = 90°), the AlInGaN/InGaN system is shown to have a smaller optical gain than the conventional InGaN/GaN system. Hence, we expect that we can obtain high-efficiency optoelectronic devices by using quaternary AlInGaN QW for relatively small crystal angles.

The paper relates to a transmissive electro-absorption modulator and a method of fabricating the optical modulator for 3D image capturing system. For 3D image capturing, the system utilizes Time-of-Flight (TOF) principle by means of high-speed optical shuttering. A 20 MHz-switching high speed optical shutter is realized by GaAs based multi-layer design with electro-absorption layers combining with optical resonance cavity and GaAs micromachining based on the etching process. Thick InGaP (4λ) layer was chosen for the transmissive membrane structure and etch-stop of GaAs wet etching. This layer also was n-type doped to enhance the electrical contact resistance. The transmissive window area is divided into 28 cells for a low device capacitance and a high switching speed, and the polyimide layer with low dielectric constant is embedded between p-pad and n-pad to reduce the leakage and parasitic capacitance. As a result, 49.5% of transmittance variation and above 37.7 MHz of switching speed are obtained to guarantee the functionality of Time-of-Flight operation of 3D camera.

Design and performance test results of a newly developed optically stimulated luminescence (OSL) measurement system are presented in this paper. Generally, different types of optical filters are used in OSL reader system to minimize the interference of the stimulation light in the OSL signal. For optically stimulation of , we have arrived at an optimal combination of the filters, i.e., GG420 filter for filtering the stimulating light source, and a combined UG11 and BG39 filter at the detecting window (PMT). By using a high luminance blue LED (Luxeon V), sufficient luminous intensity could be obtained for optically stimulation. By using various control boards, the OSL reader device was successfully interfaced with a personal computer. A software was developed to deliver required commands to operate the OSL reader by using the LabView program (National Instruments, Inc.). In order to evaluate the reliability and the reproducibility of newly designed-OSL reader. Performance testing of the OSL reader was carried out for OSL efficiency, OSL decay curve and signal to noise ratio of the standard OSL material. It was found to be comparable with that of commercial Riso reader system.

The near-fault ground motion (NFGM) is characterized by a single long period velocity pulse of large magnitude. NFGM`s have been observed in recent strong earthquakes, Izmit Turkey (1999), Kobe Japan (1995), Northridge USA (1994), etc. These strong earthquakes have caused considerable damage to infrastructures because the epicenter was close to the urban area, called as NFGM. Extensive research for the near-fault ground motion (NFGM) have been carried out in strong seismic region, but limited research have been done for NFGM in low or moderate seismic regions because of very few records. The purpose of this study is to investigate and analyze the effect of near-fault ground motions on reinforced concrete (RC) bridge piers with lap-spliced longitudinal reinforcing steels. The seismic performance of four RC bridge piers under near-fault ground motions was investigated on the shake table. In addition, a RC bridge pier is subjected to pseudo-dynamic loadings. Test results showed that large residual displacements were observed in RC bridge piers under NFGM. RC specimens on the shake table failed at relatively low displacement ductility, compared with the displacement ductility of RC bridge pier subjected to pseudo-dynamic loadings.

The purpose of this study is to investigate the seismic behavior of reinforced concrete bridge columns using shaking table tests. A computer program, named RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology), for the analysis of reinforced concrete structures was used. Material nonlinearity is taken into account by comprising tensile, compressive and shear models of cracked concrete and a model of reinforcing steel. Solution of the equations of motion is obtained by numerical integration using Hither-Hughes-Taylor (HMT) algorithm. The proposed numerical method for the seismic behavior of reinforced concrete bridge columns using shaking table tests is verified by comparison with reliable experimental results.

Through lessons in recent earthquakes, the bridge engineering community recognizes the need for new seismic design methodologies based on the inelastic structural performance of RC bridge structures. This study represents results of performance-based fragility analysis of reinforced concrete (RC) bridge. Monte carlo simulation is performed to study nonlinear dynamic responses of RC bridge. Two-parameter log-normal distribution function is used to represent the fragility curves. These two-parameters, referred to as fragility parameters, are estimated by the traditional maximum likelihood procedure, which is treated each event of RC bridge pier damage as a realization of Bernoulli experiment. In order to formulate the fragility curves, five different damage states are described by two practical factors: the displacement and curvature ductility, which are mostly influencing on the seismic behavior of RC bridge piers. Five damage states are quantitatively assessed in terms of these seismic ductilities on the basis of numerous experimental results of RC bridge piers. Thereby, the performance-based fragility curves of RC bridge pier are provided in this paper. This approach can be used in constructing the fragility curves of various bridge structures and be applied to construct the seismic hazard map.

Background and Aim: Although insulin resistance is often considered the link between obesity and non-alcoholic fatty liver disease (NAFLD), the role of insulin resistance, independent of obesity, as a NAFLD risk factor in non-obese men has been less well established. Systemic inflammation may be accompanied by insulin resistance in healthy subjects. The goal of the present study was to examine if insulin resistance and systemic inflammatory markers are independent predictors of NAFLD in non-obese men. Methods: The authors conducted a cross-sectional survey of 120 patients with NAFLD and 240 controls matched by age and body mass index. Controls had no evidence of alcohol abuse, hepatitis B or C, obesity, or previous history of diabetes, fasting hyperglycemia or hypertension. Diagnosis of NAFLD was based on an elevated alanine aminotransferase level and sonographic evidence of a fatty liver. Insulin resistance was determined using a homeostasis model assessment (HOMA-IR). Results: The age-adjusted risk of developing NAFLD was strongly associated with the elevated levels in measurements of uric acid, fasting blood sugar, triglycerides, apolipoprotein B, C-reactive protein (CRP) and HOMA-IR, and decreased levels of high density lipoprotein cholesterol and apolipoprotein A-I. Multivariate analysis based on univariate analysis indicated that an increase in CRP (odds ratio [OR] = 1.37; 95% confidence interval [CI]: 1.06–1.77) per 1 SD (1.48 mg/L) and HOMA-IR (OR = 2.28; 95% CI: 1.67–3.11) per 1 SD (0.63) were independent risk factors for NAFLD. Conclusion: Insulin resistance and systemic inflammatory response are of key importance for inducing NAFLD, particularly in apparently healthy non-obese men.

South Korea, one of East Asia’s most powerful tigers before the 1997 financial crisis, is in the process of extensive corporate governance reform. The excessive debt financing of the chaebol and the lack of accountability prevalent in Korea’s corporate governance system have been blamed for the country’s economy succumbing to the crisis. The current process of reform is taking place within a global agenda for corporate governance harmonisation, reflected in the publication of internationally acceptable principles for “good” corporate governance by, for example, the OECD and CalPERS. In this paper we present and analyse the findings of a questionnaire survey and a series of interviews conducted in Korea which canvassed the views of fund managers. Our findings indicate that Korea’s financial institutions support initiatives to reform the country’s corporate governance system. Further, they agree strongly that: investor relations need to be improved; chaebol’s accountability to shareholders should be improved; and shareholder activism should be encouraged. They also support the view that the chaebol’s activities were chiefly responsible for Korea succumbing to the East Asian crisis.

We report the observation of room temperature photoluminescence (PL) emission from GaAs/GaInAs core-multiple-quantum-well (MQW) shell nanowires (NWs) surrounded by AlGaAs grown by molecular beam epitaxy (MBE) using a self-catalyzed technique. PL spectra of the sample show two PL peaks, originating from the GaAs core NWs and the GaInAs MQW shells. The PL peak from the shell structure red-shifts with increasing well width, and the peak position can be tuned by adjusting the width of the MQW shell. The GaAs/GaInAs core-MQW shell NW surrounded by AlGaAs also shows an enhanced PL intensity due to the improved carrier confinement owing to the presence of an AlGaAs clad layer. The inclined growth of the GaAs NWs produces a core-MQW shell structure having a different PL peak position than that of planar QWs. The PL emission by MQW shell and the ability to tune the PL peak position by varying the shell width make such core-shell NWs highly attractive for realizing next generation ultrasmall light sources and other optoelectronics devices. PACS 81.07.Gf; 81.15.Hi; 78.55.Cr

A time-of-flight (TOF) based three dimensional (3D) image capturing system and its enhanced optical modulating device are presented. The 3D image capturing system includes 850nm IR emitter (typically compact Laser diodes) and high speed image modulator, so called optical shutter. The optical shutter consists of multi-layered optical resonance cavity and electro-absorptive layers. The optical shutter is a solid-state controllable filter which modulates the IR image to extract the phase delay due to TOF of the emitting IR light. This presentation especially addresses robustness issues and solutions when operated under practical environments such as ambient temperature variation and existence of strong ambient light (e.g. outdoors). The wavelength of laser diode varies substantially depending on the ambient temperature, which degrades the modulation efficiency. To get a robust operation, the bandwidth of transmittance of the optical shutter is drastically improved with a novel coupled Fabry-Perot resonance cavity design to come up with the wavelength variation of the laser diode. Also, to suppress the interference of solar irradiance to IR source signal, a novel driving scheme is applied, in which IR light and optical shutter modulation duties are timely localized, i. e. ‘bursted’. Suggested novel optical shutter design and burst driving scheme enable capturing of a full HD resolution of depth image under the realistic usage environments, which so far tackle the commercialization of TOF cameras. Design, fabrication, and evaluation of the optical shutter; and, 3D capturing system prototype, image test results are presented.

We propose and demonstrate a new electro-absorption modulator (EAM) based on coupled tandem cavities (CTC) having asymmetric tandem quantum well (ATQW) structure with separated electrode configuration to achieve large transmittance change over a broad spectral range at low driving voltage for high definition (HD) 3D imaging applications. Our theoretical calculations show that CTC with ATQW structure can provide large transmittance change over a wide spectral range at low driving voltage. By introducing separated electrode configuration, the fabricated EAM having CTC with ATQW structure shows a large transmittance change over 50%, almost three times larger spectral bandwidth compared to that of EAM having single cavity with a single thickness quantum well without significantly increasing the applied voltage. In addition, the CTC with ATQW structure also shows high speed modulation up to 28 MHz for the device having a large area of 2 mm x 0.5 mm. This high transmittance change, large spectral bandwidth and low voltage operation over a large device area for the EAM having CTC with ATQW demonstrates their huge potential as an optical image modulator for HD 3D imaging applications. (C) 2013 Optical Society of America

We suggest a Time-of-Flight (TOF) video camera capturing real-time depth images (a.k.a depth map), which are generated from the fast-modulated IR images utilizing a novel MOEMS modulator having switching speed of 20 MHz. In general, 3 or 4 independent IR (e.g. 850nm) images are required to generate a single frame of depth image. Captured video image of a moving object frequently shows motion drag between sequentially captured IR images, which results in so called ‘motion blur’ problem even when the frame rate of depth image is fast (e.g. 30 to 60 Hz). We propose a novel ‘single shot’ TOF 3D camera architecture generating a single depth image out of synchronized captured IR images. The imaging system constitutes of 2x2 imaging lens array, MOEMS optical shutters (modulator) placed on each lens aperture and a standard CMOS image sensor. The IR light reflected from object is modulated by optical shutters on the apertures of 2x2 lens array and then transmitted images are captured on the image sensor resulting in 2x2 sub-IR images. As a result, the depth image is generated with those simultaneously captured 4 independent sub-IR images, hence the motion blur problem is canceled. The resulting performance is very useful in the applications of 3D camera to a human-machine interaction device such as user interface of TV, monitor, or hand held devices and motion capturing of human body. In addition, we show that the presented 3D camera can be modified to capture color together with depth image simultaneously on ‘single shot’ frame rate.

20 Mega-Hertz-switching high speed image shutter device for 3D image capturing and its application to system prototype are presented. For 3D image capturing, the system utilizes Time-of-Flight (TOF) principle by means of 20MHz high-speed micro-optical image modulator, so called 'optical shutter'. The high speed image modulation is obtained using the electro-optic operation of the multi-layer stacked structure having diffractive mirrors and optical resonance cavity which maximizes the magnitude of optical modulation. The optical shutter device is specially designed and fabricated realizing low resistance-capacitance cell structures having small RC-time constant. The optical shutter is positioned in front of a standard high resolution CMOS image sensor and modulates the IR image reflected from the object to capture a depth image. Suggested novel optical shutter device enables capturing of a full HD depth image with depth accuracy of mm-scale, which is the largest depth image resolution among the-state-of-the-arts, which have been limited up to VGA. The 3D camera prototype realizes color/depth concurrent sensing optical architecture to capture 14Mp color and full HD depth images, simultaneously. The resulting high definition color/depth image and its capturing device have crucial impact on 3D business eco-system in IT industry especially as 3D image sensing means in the fields of 3D camera, gesture recognition, user interface, and 3D display. This paper presents MEMS-based optical shutter design, fabrication, characterization, 3D camera system prototype and image test results.

We report the antireflective property of thin film amorphous silicon (a-Si) solar cell structures based on graded refractive index structure together with theoretical analysis. Optimizations of the index profile are performed using the rigorous coupled-wave analysis method. The graded refractive index structure fabricated by oblique angle deposition suppresses optical reflection over a wide range of wavelength and incident angle, compared to the conventional structure. The average reflectance of thin film a-Si solar cell structure with the graded refractive index structure is suppressed by 54% at normal incidence due to the effective refractive index matching between ITO and a-Si, indicating a reasonable agreement with calculated results.

Although triple combination therapy containing a proton pump inhibitor (PPI) and two antibiotics is considered as a standard regimen for the first-line anti-Helicobacter pylori treatment, there are still debates on the ideal duration of treatment. The aim of this study was to compare the efficacies of 7-day and 14-day PPI-containing triple therapy.This study was performed in a randomized, multicenter, prospective manner. After upper gastrointestinal endoscopy, H. pylori-infected patients with a gastric ulcer and/or a duodenal ulcer were randomly assigned to a PAC7 group (omeprazole 20 mg or equivalent dose of other PPIs, amoxicillin 1000 mg, and clarithromycin 500 mg twice daily for 7 days) or to a PAC14 group (the same regimen as the PAC7 group but for 14 days). H. pylori status was evaluated by (13)C urea breath test 5 weeks after anti-ulcer treatment completion.A total of 598 patients were enrolled; 337 were randomized to the PAC7 group and 261 to the PAC14 group. The two groups were comparable in terms of baseline characteristics. The eradication rates of the PAC7 group were not inferior to those of the PAC14 group in both intention-to-treat analysis (71.2% vs. 75.5%) and per-protocol analysis (83.6% vs. 86.6%). Incidences of adverse events were comparable.Although the 7-day PPI-containing triple anti-H. pylori therapy is not inferior to the 14-day therapy, neither treatment duration provides acceptable eradication rate reaching 90% in per-protocol analysis. New combination regimen with higher efficacy should be developed as a first-line eradication therapy for H. pylori in Korea.

Electronic and optical properties of non-trivial semipolar AlInGaN/InGaN quantum well (QW) structures are investigated by using the multiband effective-mass theory and non-Markovian optical model. On vicinal c-plane GaN substrate miscut by a small angle (θ < 40°) from c-plane, the AlInGaN/InGaN system is shown to have ∼3 times larger spontaneous emission peak intensity than the conventional InGaN/GaN system at green wavelength. It is attributed to much larger optical matrix element of the quaternary AlInGaN/InGaN system, derived from the reduction of internal electric field induced by polarizations. This effect exceeds the performance-degrading factor of smaller quasi-Fermi-level separation for the quaternary AlInGaN/InGaN system than that for the conventional InGaN/GaN system. Results indicate that the use of quaternary III-nitride QWs on vicinal substrates may be beneficial in improving the performance of optical devices emitting green light.

The changes in total P accumulation and P compounds with time in the plough layer in a paddy soil in southern Korea were investigated in relation to the continuous application of chemical fertilizers (NPK), straw based compost (Compost), combination these two (NPK+Compost) for 31 years. Continuous fertilization increased the total and inorganic P contents in plough layers. In NPK, inorganic P fraction did not change with time, but organic P content increased significantly. Long-term application of chemical fertilizer together with compost accelerated the decrease in the organic P fraction, presumably due to promoting microbial activity in the plow layer, and then increased significantly inorganic P fraction. Compost application decreased the residual P and Fe-P fractions and then increased inorganic P fraction, in spite of continuous compost application. Increase in total, inorganic and extractable P with time may be closely related to the increase in the availability of accumulated P for rice growth.

In this paper, we propose a transmission type electro-absorption modulator (EAM) operating at 850 nm having low operating voltage and high absorption change with low insertion loss using a novel three step asymmetric coupled quantum well (3 ACQW) structure which can be used as an optical image shutter for high-definition (HD) three dimensional (3D) imaging. Theoretical calculations show that the exciton red shift of 3 ACQW structure is more than two times larger than that of rectangular quantum well (RQW) structure while maintaining high absorption change. The EAM having coupled cavities with 3 ACQW structure shows a wide spectral bandwidth and high amplitude modulation at a bias voltage of only -8V, which is 41% lower in operating voltage than that of RQW, making the proposed EAM highly attractive as an optical image shutter for HD 3D imaging applications.

High-resolution transmission electron microscopy (HRTEM) images showed that the lattice distortion of as-grown InGaP/InGaAlP multiple quantum wells (MQWs) appeared to be due to the small thickness of the alloyed layers, and that their distortion was relaxed owing to the high atomic mobility. High-angle annular dark-field scanning transmission electron microscopy images demonstrated that the chemical intermixing of Ga and Al atoms between the InAlP and InGaP alloy layers due to thermal annealing relaxed the stress of the InGaAlP layer. The atomic arrangements of the as-grown and annealed MQWs are described on the basis of the experimental results.

We report the enhancement of the minority carrier lifetime of GaInP with a lateral composition modulated (LCM) structure grown using molecular beam epitaxy (MBE). The structural and optical properties of the grown samples are studied by transmission electron microscopy and photoluminescence, which reveal the formation of vertically aligned bright and dark slabs corresponding to Ga-rich and In-rich GaInP regions, respectively, with good crystal quality. With the decrease of V/III ratio during LCM GaInP growth, it is seen that the band gap of LCM GaInP is reduced, while the PL intensity remains high and is comparable to that of bulk GaInP. We also investigate the minority carrier lifetime of LCM structures made with different flux ratios. It is found that the minority carrier lifetime of LCM GaInP is ∼37 times larger than that of bulk GaInP material, due to the spatial separation of electrons and holes by In-rich and Ga-rich regions of the LCM GaInP, respectively. We further demonstrate that the minority carrier lifetime of the grown LCM GaInP structures can easily be tuned by simply adjusting the V/III flux ratio during MBE growth, providing a simple yet powerful technique to tailor the electrical and optical properties at will. The exceptionally high carrier lifetime and the reduced band gap of LCM GaInP make them a highly attractive candidate for forming the top cell of multi-junction solar cells and can enhance their efficiency, and also make them suitable for other optoelectronics devices, such as photodetectors, where longer carrier lifetime is beneficial.

A 20-MHz switching high-speed light-modulating device for three-dimensional (3-D) image capturing and its system prototype are presented. For 3-D image capturing, the system utilizes a time-of-flight (TOF) principle by means of a 20-MHz high-speed micromachined electro-absorptive modulator, the so-called optical shutter. The high-speed modulation is obtained by utilizing the electro-absorption mechanism of the multilayer structure, which has an optical resonance cavity and light-absorption epilayers grown by metal organic chemical vapor deposition process. The optical shutter device is specially designed to have small resistor–capacitor–time constant to get the high-speed modulation. The optical shutter is positioned in front of a standard high-resolution complementary metal oxide semiconductor image sensor. The optical shutter modulates the incoming infrared image to acquire the depth image. The suggested novel optical shutter device enables capturing of a full high resolution-depth image, which has been limited to video graphics array (VGA) by previous depth-capturing technologies. The suggested 3-D image sensing device can have a crucial impact on 3-D–related business such as 3-D cameras, gesture recognition, user interfaces, and 3-D displays. This paper presents micro-opto-electro-mechanical systems-based optical shutter design, fabrication, characterization, 3-D camera system prototype, and image evaluation.

For reliable three dimensional (3D) imaging system, it is necessary for the optical shutter to have a wide spectral bandwidth operation and enhanced modulation depth. We propose an electro-absorption modulator (EAM) based on coupled Fabry-Perot cavities with micro-cavity (CCMC) which uses asymmetric tandem quantum wells (ATQWs) to obtain improved spectral bandwidth and enhanced modulation depth. Several modulator designs are investigated to obtain improved modulation performance such as wider spectral bandwidth and enhanced modulation depth. It was found that among all the studied modulator geometries, CCMC structure with ATQWs provides the widest spectral bandwidth of 9.6nm and high modulation depth in excess of 50% at -24V, which is good agreement with theoretical calculations. These results suggest that EAM has excellent potential as optical shutter for 3D imaging application. (C) 2012 Optical Society of America

Lateral composition modulated (LCM) GaInP structures were grown on (001) GaAs substrate by molecular beam epitaxy with different V/III flux ratios. Band gap of LCM structures could be tuned from 1.93 eV to 1.83 eV by decreasing flux ratio while maintaining the same photoluminescence intensity, enhanced light absorption, and widened absorption spectrum. It is shown that for band gap tuning of LCM structures, flux ratio adjustment is a more viable method compared to growth temperature adjustment.

We report the first experimental demonstration of an active interfacial shear microrheometer (ISMR) that uses a particle trapped by oscillating optical tweezers (OT) to probe the shear modulus G(s)(*)(ω) of a gas/liquid interface. The most significant advantages of the oscillating OT in a rheology study are: (1) very high sensitivity compared to other active microrheology methods and (2) the ability to measure both the real and imaginary components of the complex shear modulus without relying on the use of Kramers-Kronig relation, which can be problematic at low frequencies for most of the passive methods. We demonstrate the utilities of our ISMR in two case studies: (1) a 1,2-dipalmitoyl-sn-glycero-3-phosphocholine monolayer and (2) a composite of poly(styrene sulfonate) and dioctadecyldimethylammonium at the air/water interface in regimes where no other active instruments can explore.

We demonstrate a highly tolerant and highly reflective broadband a-Si distributed Bragg reflector fabricated by oblique angle deposition. By tuning the refractive index of an a-Si film, a high index contrast material system was achieved. The highly tolerant and broadband reflective characteristics of the a-Si distributed Bragg reflector were investigated by calculation and fabrication. A broad stop band (Δλ/λ = 33.7%, R>99%) with only a five-pair a-Si distributed Bragg reflector was achieved experimentally. The size-, feature- and substrate-independent method for highly reflective Bragg reflectors was realized by simple oblique angle evaporation.

Thin ZnO films were directly grown on p-Si(1 0 0) substrates by photoinduced electrodeposition under illumination. In this case, p-Si wafer behaves as a photocathode. At the initial deposition stage, it has been found that the ZnO films grew through three-dimensional instantaneous nucleation followed by diffusion-limited growth mode. In this study, we report that the conductivity type of ZnO films can be changed from n-type to p-type by varying the relative concentration of oxygen in ZnO films through the thermal treatment in air ambient without any doping process. The electrical properties of ZnO/p-Si heterojunctions were investigated via current–voltage (I–V) characteristics. These heterojunctions showed good diode-like, rectifying I–V characteristics and the turn-on voltages of the n-ZnO/p-Si and p-ZnO/p-Si heterojunctions were found to be 0.56 and 0.46 V. From the analysis of temperature dependence of the I–V characteristics, these heterojunctions exhibited that the charge carriers are mainly transported by the activation of the carriers across the barrier height but in a low voltage region under forward bias, transported through the multi-step tunnelling-assisted carrier capture-emission mechanism.

ASSOCIATION BETWEEN LITHOGENESIS AND ANATOMICAL CHARACTERISTICS OF CYSTIC DUCT AND JUXTAPAPILLARY DUODENAL DIVERTICULUM. Hyun Seung Kim, Chang Young Park. Yong Kyun Cho, Woo Kyu Chun, Jung II Son, Byung Ik Kim, Eul Soon Jung, Jun Ho Shin, Hwa Young Lee. Sang Jong Lee, Kangbuk Samsung Hosp Sungkyunkwan Univ Sch of Medicine, Seoul, South Korea; CHA Gen Hosp Pochon CHA Univ Coli of Medicine, Seoul, South Korea.