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Recently, the NORSOK standards, which regulate noise and vibration on offshore platforms, were strengthened by prohibiting the use of glass wool for environmental and safety reasons. In addition, the use of sound-absorbing materials in panels and silencers was prohibited. Therefore, developing a silencer that does not use sound-absorbing materials is necessary. In this study, a bandgap expressed by acoustic characteristics of a periodic structure was applied to develop a silencer without sound-absorbing materials. The bandgap is formed in a frequency range in which propagation of acoustic waves is suppressed by setting a specific distance between single units based on periodic structural theory. The designed silencer evaluates the noise attenuation effect of the periodic structure based on a fluid-structure coupling finite-element equation for a plane wave in a stationary medium. In addition, the silencer model was selected by analyzing the regenerated noise originating from the periodic structure in the flow duct. This flow noise is used to analyze the propagation of sound waves based on the FW-H equation. This is achieved by employing the Lighthill acoustic analogy to predict the flow-induced sound pressure. Furthermore, compressed air was injected at the end of the duct in the flow noise experiment to perform measurements. The results from the acoustic and flow noise experiments were compared to confirm the effect of the flow in the duct on noise generation. Moreover, the flow noise analysis based on the flow velocity elucidated the effect of the periodic structure on the flow. In addition, the analysis results were used to investigate its performance of the silencer with the periodic rod arrangement considering the flow noise in the duct and predict its acoustic characteristics in the bandgap frequency range.

Time-lapse of user captured video becomes popular in many applications recently, non-uniform sampling and digital video stabilization (VS) are usually two independent steps to keep meaningful contents and provide stabilized output. However, non-uniform sampling may produce large sampling interval and then result in larger motion, this would beyond the stabilization ability of VS and produce unpleasant output. To address this problem, we propose a new auto time-lapse framework, which selects frames not only based on camera motion scenarios, but also refer to the smoothed camera trajectory and considering VS ability according to Field of View (FOV) loss constraint. More specific, we introduce an advanced Markov chain (MC) model, in which smoothed camera trajectory, FOV loss constraint of VS, camera motion scenario, and sampling interval similarity between consecutive frames are encoded as potential functions. Finally, dynamic programming (DP) is employed to find the best non-uniform sampling. Experimental results demonstrate that the proposed method not only achieves pleasant and meaningful non-uniform sampling, but also provides satisfactory stabilization performance. The whole algorithm can work in real time during video recording on mobile device.

[Purpose] This study aimed to compare changes in the center of pressure between healthy subjects and patients with spinal cord injury and to provide basic information to these patients for improving their sitting balance. [Subjects and Methods] A total of 12 healthy subjects without histories of neurological or psychiatric disorders and 12 patients with spinal cord injuries were recruited. In all subjects, a change in the center of pressure during the performance of the modified functional reach test was measured using a Force Sensing Array system while the subjects were seated in a wheelchair. In the spinal cord injury group, the change in the center of pressure was highest when subjects reached forward while holding a gym ball. [Results] In the spinal cord injury group, the change in the center of pressure was highest when subjects reached forward while holding a gym ball. A significant correlation between forward reaching of the upper limbs with shoulders at 90° flexion and a change in the center of pressure was found. [Conclusion] Our findings suggest that the combination of functional reaching and the change in the center of pressure assessment is novel enough to be attempted to achieve sitting balance control in patients with spinal cord injury. The findings can provide clinical interventions that contribute to the improvement in the balance ability of wheelchair-dependent individuals.

[Purpose] The purpose of this study was to evaluate the influence of arm and leg posture elements on symmetrical weight bearing during Sit to Stand tasks in chronic stroke patients. [Subjects and Methods] The subjects were diagnosed with stroke and 22 patients (15 males and 7 females) participated in this study. All participants performed Sit to Stand tasks on three foot postures and two arm postures. Two force plates were used to measure peak of vertical ground reaction force and symmetrical ratio to peak Fz. The data were analyzed using independent t-test and two-way repeated ANOVA. [Results] The results of this study are as follows: 1) Peak Fz placed more weight in non-paretic leg during Sit to Stand. 2) A symmetrical ratio to Peak Fz indicated significant difference between foot and arm posture, and had non-paretic limb supported on a step and paretic at ground level (STP) and grasped arm posture that lock fingers together with shoulder flexion by 90°(GA) (0.79 ± 0.09). [Conclusion] These results suggest that STP posture of the legs and GA posture of the arms should be able to increase the use of the paretic side during Sit to Stand behavior and induce normal Sit to Stand mechanism through the anterior tilt of the hip in clinical practices, by which loads onto the knee joint and the ankle joint can be reduced, and the trunk righting response can be promoted by making the back fully stretched. The outcome of this study is expected to be a reference for exercise or prognosis of Sit to Stand in stroke patients.

Meta-structures composed of honeycomb-shaped unit cells were built to have high sound-proof and heat-exhaust performance. Each unit cell operates as a Helmholtz resonator (HR) and a lumped inertance muffler (LIM), resulting in sound energy dissipation at specific tonal and broadband frequencies and minimal noise transmission. This cover structure allowed heat-exhaust through the open cross-sectional area. The acoustic characteristics of the meta-structure fabricated using ABS were measured by the four microphone method. The bandgap at specific frequencies and noise reduction at high frequencies were investigated. The significant change of negative effective mass density and the purely complex value of the wave speed were measured at the resonant frequency band of HR. The theoretical model was suggested to analyze the noise reduction mechanism. The designed meta-structure was applied as the covers of the refrigerator machine room and the top-loading washing machine for demonstrating a practical noise control applications. The suggested structures were designed to meet same geometric constraints as the original cover both in dimensions and open area for heat exhaust. To evaluate the noise reduction performances, the sound radiations from the operating refrigerator and washing machine were measured. The noise transmitted through the panel was significantly reduced by using the proposed cover in the specific frequency bands. For the washing machine, the efficiency depended on the type of the operating process. Noise reduction was large during the fill and wash process, whereas, minimal during drain and spin process. Because the resonance and cut-off frequencies of HR and LIM were designed as 570 and 300 Hz, respectively, the effectiveness was minimal for low frequency sounds. The temperature of the operating compressor of refrigerator and the spinning motor of washing machine showed minimal increase suggesting identical heat exhaust performances. The suggested meta-structure induced large noise reduction without influencing heat exhaust by similar open area for fluid flows as the original cover.

Cadavers are often used to measure the material properties of muscle via the static tensile loading test. However, the mechanical properties of the cadaver are different from that of in vivo muscle. In this work, a new way to measure the stiffness of in vivo muscle was proposed based on a vibration test combined with measured electromyography (EMG) signals. The stiffness of the biceps brachii muscle during isometric contractions with various weights (0 - 11 kg) was measured from the vibration test utilizing support properties of a spring attached to a mass. The relationship between the load level, the EMG signal, and the muscle stiffness was investigated and a multiple- spring model for biceps brachii muscle was newly suggested. Also, simulation using a commercial bio-mechanics simulation software (LifeMOD) was conducted to verify the developed muscle spring model and the measured stiffness of the in vivo muscle. The in vivo stiffness of the biceps brachii measured experimentally agreed well with the simulation result.

A composite sound absorption structure constructed with fibrous layer and carbon fibers was proposed and its acoustic performance was experimentally studied. Proposed structure’s sound absorption properties depended on the gap of the air cavity between fibrous layers. To increase the absorption efficiency, carbon fiber was applied between the gaps. The normal incidence sound absorption coefficients and specific acoustic impedance were measured with the two-microphone impedance tube method to determine the effects of the carbon fibers on the acoustic properties. Random incidence absorption coefficients were determined from the measured specific acoustic impedances of the proposed structures. The measured results were compared for various fractions of carbon fibers. Modified wave propagation equations with empirical density equations were suggested to predict the acoustic behavior of the proposed absorbers. After application of the carbon fibers, the composite helical-shaped sound absorber showed better sound absorption efficiency under both normal and random incidence conditions. This suggested that the carbon fibers introduced additional sound dissipation when properly distributed along the gap of the sound absorber.

Sound radiation from electric motor-driven vehicles is negligibly small compared to sound radiation from internal combustion engine automobiles. When running on a local road, an artificial sound is required as a warning signal for the safety of pedestrians. In this study, an engine sound was synthesized by combining artificial mechanical and combustion sounds. The mechanical sounds were made by summing harmonic components representing sounds from rotating engine cranks. The harmonic components, including not only magnitude but also phase due to frequency, were obtained by the numerical integration method. The combustion noise was simulated by random sounds with similar spectral characteristics to the measured value and its amplitude was synchronized by the rotating speed. Important parameters essential for the synthesized sound to be evaluated as radiation from actual engines were proposed. This approach enabled playing of sounds for arbitrary engines. The synthesized engine sounds were evaluated for recognizability of vehicle approach and sound impression through auditory experiments.

This paper presents sound absorbing structure constructed using multiple layers of fibrous papers. Sound absorbing materials converts sound wave into thermal energy due to the porosity. The proposed sound absorbing structure has helical-like shapes in layered format with cyclic winding of the mulberry papers and coconut fibers. The acoustic properties changes depending on the thickness of the air cavity between the thin layers and porosity of the layers themselves. Sound absorption coefficients were measured using two-microphone impedance tube in order to investigate the acoustic property variations with porosity. The measured results were compared to predictions utilizing wave propagations through a slit for verification of the sound absorbing mechanism. A simple method for improving the sound absorption with less material by composite structure is proposed and verified through the experiment. Dynamic stiffness and loss factor of the helical-shaped sound absorbers were measured and compared by analyzing supporting properties to the vibrating beam. Depending on the construction method, the frame dynamic properties showed variation even when the sound absorption was identical. This information is required for optimal design of absorbing layers for specific noise control applications.

경두개직류전류자극(tDCS)은 낮은 직류 전류 강도를 사용하여 대뇌피질의 자발적인 신경학적 활동의 흥분성을 증가 또는 감소시키는 신경조절 기법이다. 본 연구의 목적은 tDCS를 적용한 후 다양한 감각 기능의 변화를 측정하는데 있다. tDCS의 효과를 측정하기 위해 CPT 검사를 50명의 건강한 대상자에게 단일 기간(8월4일에서 8월29일), 단일 공간, 단일 맹검법으로 무작위 배정하였다. 신경전도검사는 우세 손의 말초신경 병변을 구별하기 위해 정중 감각과 운동신경을 측정하였다. 대상자들은 각 25명 씩 대뇌피질의 DLPFC의 tDCS 자극군과 대뇌피질의 DLPFC의 tDCS 위자극군으로 2개의 다른 조건 아래서 1 mA의 전류강도로 15분씩 양극 tDCS로 적용하였다. 촉각, 빠른 통증과 느린 통증을 각각 평가하기 위해 우세한 제 2수지에 2000, 250, 그리고 5 Hz의 주파수로 CPT 검사인 Neurometer $^{(R)}$ 를 이용하여 수치들을 기록하였다. DLPFC의 양극 tDCS 자극군의 CPT 수치들에서는 250과 5 Hz에서 통계적으로 유의한 증가를 보였다. 양극 tDCS 위자극군의 모든 CPT 수치들은 감소하였다. 이러한 결과는 DLPFC의 양극 tDCS가 건강한 대상자들의 감각 지각과 통증 역치들을 조절할 수 있다는 것을 보여준다. 따라서 본 연구는 재활과 통증 치료 분야에서 유용한 치료 방법 중 하나로 제시할 수 있을 것으로 생각한다. 【Transcranial direct current stimulation (tDCS) is a neuromodulatory technique that delivers a low-intensity direct current to the cortical areas, thereby facilitating or inhibiting spontaneous neuronal activity. This study was designed to examine the changes in various sensory functions after tDCS. A single-center, single-blinded, randomized trial was conducted to determine the effect of a single session (August 4 to August 29) of tDCS with the current perception threshold (CPT) in 50 healthy volunteers. Nerve conduction studies (NCS) were performed in relation to the median sensory and motor nerves on the dominant hand to discriminate peripheral nerve lesions. The subjects received anodal tDCS with 1mA for 15 minutes under two different conditions, with 25 subjects in each group. The conditions were as follows: tDCS on the dorsolateral prefrontal cortex (DLPFC) and sham tDCS on DLPFC. The parameters of the CPT was recorded with a Neurometer $^{(R)}$ at frequencies of 2000, 250 and 5 Hz in the dominant index finger to assess the tactile sense, fast pain and slow pain, respectively. In the test to measure the CPT values of the DLPFC in the anodal tDCS group, the values increased significantly in all of 250 and 5 Hz. All CPT values decreased for the sham tDCS. These results showed that DLPFC anodal tDCS can modulate the sensory perception and pain thresholds in healthy adult volunteers. This study suggests that tDCS may be a useful strategy for treating central neurogenic pain in rehabilitation medicine.】

We present a CMOS image sensor (CIS) with phase detection auto-focus (PDAF) in all pixels. The size of photodiode (PD) is 0.64μm by 1.28μm, the smallest ever reported and two PDs compose a single pixel. Inter PD isolation was fabricated by deep trench isolation (DTI) process in order to obtain an accurate AF performance. The layout and depth of DTI was optimized in order to eliminate side effects and maximize the performance even at extremely low light condition up to 1lux. In particular the AF performance remains comparable to that of 0.70μm dual PD CIS. By using our unique technology, it seems plausible to scale further down the size of pixels in dual PD CIS without sacrificing AF performance.

The friction between rubber and glass is a primary factor in inducing squeal noises from vehicle wiper systems on automotive windscreens. The squeal noise occurs without periodicity only when specific conditions are met for particular vehicles. In this study, an experimental setup for consistent squeal noise generation was implemented using a wiper blade on a rotating windscreen glass. The waviness of the rotating glass induced variation of the wiper blade sliding velocity and friction coefficients, simultaneously. The squeal noise generation mechanism was investigated by analysing the effects of surrounding temperature and washer fluid on the vibration instability. This analysis provided needed information to design a vehicle wiper system with minimal squeal noise generation during normal operations.

Transcranial direct current stimulation (tDCS) is a neuromodulatory technique that delivers low-intensity direct current to cortical areas, thereby facilitating or inhibiting spontaneous neuronal activity. This study was designed to investigate changes in various sensory functions after tDCS. We conducted a single-center, single-blinded, randomized trial to determine the effect of a single session of tDCS with the current perception threshold (CPT) in 50 healthy volunteers. Nerve conduction studies were performed in relation to the median sensory and motor nerves on the dominant hand to discriminate peripheral nerve lesions. The subjects received anodal tDCS with 1 mA for 15 minutes under two different conditions, with 25 subjects in each groups: the conditions were as follows tDCS on the primary motor cortex (M1) and sham tDCS on M1. We recorded the parameters of the CPT a with Neurometer(R) at frequencies of 2000, 250, and 5 Hz in the dominant index finger to assess the tactile sense, fast pain and slow pain, respectively. In the test to measure CPT values of the M1 in the tDCS group, the values of the distal part of the distal interphalangeal joint of the second finger statistically increased in all of 2000 Hz (p=.000), 250 Hz (p=.002), and 5 Hz (p=.008). However, the values of the sham tDCS group decreased in all of 2000 Hz (p=.285), 250 Hz (p=.552), and 5 Hz (p=.062), and were not statistically significant. These results show that M1 anodal tDCS can modulate sensory perception and pain thresholds in healthy adult volunteers. The study suggests that tDCS may be a useful strategy for treating central neurogenic pain in rehabilitation medicine.

In this paper, we develop pixels with concentric-photogates for applications in time-of-flight 3-D image sensors with single-tap architecture. The pixel uses a buried-channel device and features a reduced effective electron transit length, for the rapid transfer of a signal electron. A reduction in the interpixel irregularity of signal levels and a consequent increase in the demodulation signal amplitude are observed in the single-tap operation mode as opposed to the multitap operation mode. Specifically, we are able to achieve a demodulation contrast higher than 50% from 20 MHz modulation of an 850 nm light-emitting diode illumination. Finally, we construct a sensor composed of 198 × 108 concentric photogate pixels, each with a pitch of 28 μm, and use it to generate a 3-D image conveying gross distance information and detailed object features with a distance error of less than 1% over a range of 1 to 7 m.

The purpose of his study was to analyze the environmental and the medical factors of prematurely discharged patients in a rehabilitation hospital. The subjects were 107 inpatients. The data were collected using self-report questionnaire and analyzed using the SPSS Win 19.0 program. In result, Firstly, general selection of hospitals was the ‘Recommendation‘ 35.5%, Environmental dissatisfaction factors are Hospital facilities 37.4%. Hospital choice is the highest 'Acquaintances' 23.4%. Second, the lowest group about professionalism, kindness, and description of explanation on satisfaction in survey is group of care workers for the sick. The highest group is physical and occupational therapist. Third, the satisfaction regarding medical procedures of administrative work, waiting time and medical expenses is the highest normal. Hospital facilities in one of the highest factors in environmental dissatisfaction is can be considered as an element of patient departure because of not much number of nervous special hospitals. Medical dissatisfaction factors is the lowest satisfaction of care worker even if those spend much time. this is the focus leaving hospital. Therefore, factors care workers on service satisfaction and dissatisfaction in analysis and problem solving is considered that the need to find ways to improve the quality of service care workers

[Purpose] This study assessed vertebral and femoral bone mineral density in adult females. [Subjects and Methods] A total of 314 females in their 40s to 70s were divided into normal, osteopenia, and osteoporosis groups and their vertebral and femoral bone mineral densities were compared. [Results] Comparisons of T scores revealed significant differences among measurements of the third lumbar vertebra, femoral neck, Ward’s triangle, and femoral trochanter. Pearson correlation coefficients were used to assess differences between the vertebral and femoral measurements, and significant differences and positive correlations were observed among third lumbar vertebra, femoral neck, Ward’s triangle, and femur trochanter in the normal group. [Conclusion] Females in the normal, osteopenia, and osteoporosis groups showed significant differences in their third lumbar vertebrae. The lack of significant differences among measurements in the osteoporosis group in this study suggests that patients with osteoporosis require careful and accurate diagnosis.

Nanoscale manipulation of surface charges and their imaging are essential for understanding local electronic behaviors of polar materials and advanced electronic devices. Electrostatic force microscopy and Kelvin probe force microscopy have been extensively used to probe and image local surface charges responsible for electrodynamics and transport phenomena. However, they rely on the weak electric force modulation of cantilever that limits both spatial and temporal resolutions. Here we present a field effect transistor embedded probe that can directly image surface charges on a length scale of 25 nm and a time scale of less than 125 μs. On the basis of the calculation of net surface charges in a 25 nm diameter ferroelectric domain, we could estimate the charge density resolution to be as low as 0.08 μC/cm(2), which is equivalent to 1/20 electron per nanometer square at room temperature.

This paper estimates technical efficiency of industrial water in order to afford some information for improving the efficiency of government water management policy. To estimate technical efficiency, this paper uses data envelopment analysis. The result shows that the average pure technical efficiency of industrial water is 0.407. This estimate is less than the estimates when all inputs are considered as variables in the previous researches. This result means that the managers may have not tried to improve the efficiency of industrial water usage since the cost for industrial water is trivial compared to other inputs. In addition, this result shows that the previous researches which assume that all inputs are used in efficient way may give a biased results.

The resistive probe, which can detect the variation in probe resistance while scanning over positive/negative biased bits, has been considered as the one of the most suitable candidate for used as a high-speed, ultralarge-storage systems. Ultralarge-storage density has been demonstrated by the electrical recording technique in which surface charge is read in ferroelectric materials, which is named as scanning resistive probe microscopy (SRPM). Because of the difficulty of fabricating, the SRPM device little has been previously done on relating probe properties with process parameters. As it is important in probe design to analyze the properties of sensitivity and resolution for different process and device parameters, the parameters of the fabricated microscope are embedded in the simulation performed in this study. To obtain the optimum resistive probe design, we analyze the effect of different process parameters on the properties. In the first part of the paper, the device structure fabricated to identify the electrostatic charge effects between the tip and the poly silicon domain (surface) is presented. In the second part, we explain the process conditions of the resistive probe. In the third part, we present the sensitivity and resolution for different process conditions. The probe is placed in contact with a poly silicon domain (surface) to measure the field sensitivity, and a 0.3% resistance change per voltage applied to the surface is detected with a spatial resolution of less than 1000 nm. The sensitivity and resolution for different implantation doses, wet oxidation time, and resistances in the high-doped n-type region are also presented. We found that there is a correlation between sensitivity and resolution for different implantation doses and annealing times. Although the sensitivity decreases as resistance increases, the change is less than 10% even at a resistance of 200 Ω. Therefore, the resistance of the cantilever can be neglected in our study of probe sensitivity.

본 연구는 수자원정책의 효율성 제고를 위한 판단 자료 제공을 목적으로 업종별 공업용수의 한계생산가치 및 공업용수의 가격탄력성을 추정하였다. 두 가지 형태의 생산함수를 설정하여 추정한 공업용수의 한계가치 및 가격탄력성을 추정 결과를 보면 공업용수의 한계가치는 산업별로 차이가 있으나 공업용수의 평균 가격에...

Grain/domain interaction and its effect on bit formation were performed by piezoelectric force microscopy (PFM) on arrays of poled nanosize domains in Pb(Zr0.4Ti0.6)O3 thin films grown by sol-gel route. In both pulse width variation and pulse voltage variation, bit formation was observed. It was found that the grain boundary plays a role of domain growth stopper. Among two different variations, the pulse width variation only has a linear relationship between pulse width and bit size. The obtained results imply that pulse width variation is much easier to control the bit size in probe-based data storage.

A new two-axis positional error detection algorithm for probe storage is proposed. Using only probes, this algorithm can detect two-axis positions simultaneously and continuously for off-track control and synchronization. Two decomposition signals are multiplied to the probe readback signal while vibrating the scanner in low frequency of the specific value to extract two position error signals from it. In addition, the same algorithm using only one decomposition signal is proposed. Because this algorithm provides very precise positional errors continuously, off-track and synchronization errors can be controlled to zero continuously, and the sensitivities to disturbances can be reduced

Very fast, precise and robust servo algorithm and tracking algorithm for a probe storage system are proposed, which use only probes without any additional high-resolution position sensors. Servo algorithm uses the values read by servo probes as the coordinate of every data bit with one-to-one correspondence so that it provides high accuracy, short seek-time, and robustness. Also the concept of virtual subsection of data field is introduced to reduce the number of the servo probes. Tracking algorithm can detect two-axis position errors used for off-track control and synchronization independently and continuously. By vibrating the scanner and by multiplying two decomposition signals, position errors are modulated and demodulated from probe reading signal. Servo+track code is designed to reduce total number of additional probes for servo and tracking and to have stable noise characteristics.

[Purpose] While recent studies have reported that cardiac rehabilitation is an effective treatment, there have been few studies of its effects in rehabilitation for acute coronary syndrome (ACS). Therefore, the purpose of this study was to identify the effects of a home-based exercise training using a wireless electrocardiogram (ECG) monitoring device on ACS patients. [Subjects] Fifty ACS patients were randomly divided into a experimental group of 25 patients and a control group of 25 patients. [Methods] The experimental group received education on the training before discharge from hospital and started home-based exercise training two weeks after discharge from hospital. The control group received conventional treatments. The left ventricular function was measured in both groups before the intervention at and 12 weeks, at the end of the intervention. [Results] Both the experimental group and the control group showed significant improvements in the left ventricular ejection fraction and number of regional wall motion abnormalities. In the comparison of the two groups, the experimental group showed a significantly greater decline in regional wall motion abnormalities than the control group. [Conclusion] Home-based exercise training implemented with a wireless monitoring device was effective at improving the left ventricular function of ACS patients.

In time-of-flight 3D application, sensors detect modulated light responses for depth calculation. To measure the distance, time-of-flight camera needs 4 phases. Typical method needs to 4 frames to obtain 4 phases which has motion blur, low frame rate. To solve those problems 2-tap operation was considered. But it has a problem in removing fixed pattern noise. In this paper, we propose the phase to reduce disadvantages in typical Time-of-flight camera. We will analyze the mosaic pattern with considering noise. And we compare the performance among mosaic patterns and typical method.

3D time-of-flight depth cameras utilize modulated light sources to detect the distance to objects as phase information. A serious limitation may exist in cases when multiple depth time-of-flight cameras are imaging the same scene simultaneously. The interference caused by the multiple modulated light sources can severely distort captured depth images. To prevent this problem and enable concurrent 3D multi-camera imaging, we propose modulating the camera light source and demodulating the received signal using sequences of pulses, where the phase of each sequence is varied in a pseudo-random fashion. The proposed algorithm is mathematically derived and proved by experiment.

In this paper, we proposed a new technique for demosaicing a unique RGBZ color-depth imaging sensor, which captures color and depth images simultaneously, with a specially designed color-filter-array (CFA) where two out of six RGB color rows are replaced by “Z” pixels that capture depth information but no color information. Therefore, in an RGBZ image, the red, green and blue colors are more sparsely sampled than in a standard Bayer image. Due to the missing rows in the data image, commonly used demosaicing algorithms for the standard Bayer CFA cannot be applied directly. To this end, our method first fills-in the missing rows to reconstruct a full Bayer CFA, followed by a color-selective adaptive demosaicing algorithm that interpolates missing color components. In the first step, unlike common bilinear interpolation approaches that tend to blur edges, our edge-based directional interpolation approach, derived from de-interlacing techniques, emphasizes reconstructing more straight and sharp edges with fewer artifacts and thereby preserves the vertical resolution in the reconstructed the image. In the second step, to avoid using the newly estimated pixels for demosaicing, the bilateral-filter-based approach interpolates the missing color samples based on weighted average of adaptively selected known pixels from the local neighborhoods. Tests show that the proposed method reconstructs full color images while preserving edges details, avoiding artifacts, and removing noise with high efficiency.

We report a resistive probe that detects electric field by field-induced resistance changes in a small resistive region at the apex of the tip and demonstrate a method of imaging ferroelectric domains at high speed, which is named scanning resistive probe microscopy (SRPM). We designed and fabricated the probe by self-aligning process that readily implemented the resistive region at the tip apex. In order to measure the field sensitivity, we contacted the probe with a thermally oxidized silicon sample and detected a 0.3% resistance change per volt applied to the sample. We obtained domain images of freshly cleaved triglycine sulfate (TGS) single crystal by contact mode SRPM. The operating voltage of the probe was 4 V and the scan rate and size were 2 Hz and 40×40 μm2, respectively. We controlled the polarization of Pb(Zr0.4Ti0.6)O3 (PZT) by applying voltage between the resistive tip and the bottom electrode of PZT, and acquired the domain images with the same tip at 2 Hz scan rate. By controlling and dete...

It is important to inspect clamped parts of a produced vehicle in the manufacturing process non-destructively. In this study, a measuring device of axial force is suggested by utilizing relations between wave propagation characteristics of a beam and a clamping force. Experiments were carried out to determine characteristics of vibration signals for the structure designed for inspection. Neodymium magnet was utilized as the components of the device to attach to the joint without any damage to the products. A rectangular parallelepiped magnet was used to detect the change in the wave propagation speeds in the structure. The change in the wave propagation through the bolt was measured and used in estimation of the axial force. The correlation coefficient was calculated to quantify the change in the wave propagation characteristics. The coefficient was utilized to determine the axial force of the bolted joint by the experiment. The proposed method was applied to actual U-bolts to validate the methodology.

This paper presents a BSI(backside-illumination) 14µm-pixel QVGA CMOS image sensor SOC(System On a Chip) measuring TOF(Time-Of-Flight) by 20MHz-intensity modulation of 850nm-wavelength light. The 34% of overall QE(Quantum Efficiency) at 850nm-wavelength is acquired by BSI structure and optimized micro-lens. The DE(Depth Error) less than 1.5% within 6m is achieved with imaging lens of f/1.2 and LED array of which the optical intensity is 0.6W/m2 at 1m-distance. Additionally, the depth linearity is measured as that the coefficient of determination is equal to 0.9999. In order to operate under background light illumination on a scene, dual CG(Conversion Gain) scheme is implemented in each pixel.

We performed piezoelectric force microscopy (PFM) measurements on arrays of poled nanosize domains in 150 nm thick 〈111〉 preferentially oriented Pb(Zr0.4Ti0.6)O3 films grown by chemical solution deposition. Each domain of arrays was characterized by dot, egg, and ring structures depending on the pulse width ranging from 1 to 5 ms. The PFM measurements were followed by heat treatments at successively higher temperatures of 100 °C, 130 °C, and 160 °C for 30 min with rapid cooling down to room temperature before each measurement. The retention loss phenomena of the bits were characterized by measuring the number and dimension change of the remaining data bits. It was concluded that the ring-structured bit arrays, which represent fully penetrating domains through the film thickness, were the most stable form in terms of retention loss characteristics.

A single-tap concentric photogate pixel of 28 µm pitch is developed for application to time-of-flight (ToF) three dimension (3D) image sensors. The 198×108 ToF pixel array exhibits demodulation contrast higher than 50% and distance error less than 1%, over 1 to 7 m range using 20MHz modulation of 850 nm light emitting diode (LED) illumination.

A full-color image is obtained from the interpolated RGB images by use of an appropriate demosaicing algorithms but some interpolation errors can not be avoidable. In this paper, new image capturing system is proposed which has an actuator to move the image sensor in two-axis and very simple image reconstruction algorithm, and can enhance the image quality since it does not involve any demosaicing process.

New bit array pattern and detection algorithm for hard disk drive (HDD) with patterned media are proposed. The width of the reader is larger than a bit width, of which the fabrication cost is lower than a bit-size compatible reader. It can read several sub-tracks simultaneously, in which the bits are patterned with different phase. The readback signal is superposed by each bit response and we can extract the bit information easily because of its phase difference.

Resistive probe can detect the variation of electric field from a media by its current variation. Equivalently it is a variable resistor, which is sensitive to electric field. However, the experimental results show that another mechanism is involved in it and it is considered to have a relationship with the topography of the media. In this paper, this newly observed mechanism is explained as thermal effect with simulation results. This can affect the signal quality as a noise source or detection limitation of the field variation or, in other hand can be used as a highly localized thermal tip sensor.

This paper presents a two-dimensional heat-exhaust and sound-proof acoustic meta-structure exhibiting tunable multi-band negative effective mass density. The meta-structure was composed of periodic funnel-shaped units in a square lattice. Each unit cell operates simultaneously as a Helmholtz resonator (HR) and an extended pipe chamber resonator (EPCR), leading to a negative effective mass density creating bandgaps for incident sound energy dissipation without transmission. This structure allowed large heat-flow through the cross-sectional area of the extended pipe since the resonance was generated by acoustic elements without using solid membranes. The pipes were horizontally directed to a flow source to enable small flow resistance for cooling. Measurements of the sound transmission were performed using a two-load, four-microphone method for a unit cell and small reverberation chamber for two-dimensional panel to characterize the acoustic performance. The effective mass density showed significant frequency dependent variation exhibiting negative values at the specific bandgaps, while the effective bulk modulus was not affected by the resonator. Theoretical models incorporating local resonances in the multiple resonator units were proposed to analyze the noise reduction mechanism. The acoustic meta-structure parameters to create broader frequency bandgaps were investigated using the theoretical model. The negative effective mass density was calculated to investigate the creation of the bandgaps. The effects of design parameters such as length, cross-sectional area, and volume of the HR; length and cross-sectional area of the EPCR were analyzed. To maximize the frequency band gap, the suggested acoustic meta-structure panel, small neck length, and cross-sectional area of the HR, large EPCR length was advantageous. The bandgaps became broader when the two resonant frequencies were similar.

New 2-axis positional error detection algorithm for probe-based data storage is proposed. This algorithm can detect two-axis positions simultaneously and continuously for off-track control and synchronization purposes by vibrating the scanner in low frequency of the specific value. Then two decomposition signals are multiplied to the probe readback signal to extract two position error signals from it. Since this algorithm provides very precise positional errors continuously, off-track error and synchronization error can be controlled to zero continuously and the sensitivities to disturbances can be reduced.

We suggest a new design of resistive probe (RP) for spatial resolution improvement by Si tip shape control. The major change of the new design is wedge-like probe formation rather than pyramidal shape, which results in the reduced removal of high doped volume near the slanting surface of probe. Therefore, we could reduce spatial resolution deterioration mainly due to low doped volume of the sloped surface. The newly designed resistive probe (RP) showed about 40 nm transition (which is assumed to be a distance taken signal rising from 10% to 90% of saturation level) in bit writing and reading experiment on the real ferroelectric media, which is a few times improvement compared to the original one.

The admittance of one-port electrostatic actuator are modeled using the steady-state sinusoidal response. Also the admittance of the differential type actuator is derived taking the practical conditions into consideration, although it has no admittance in ideal case. It is shown as a function of biasing error, driving error, and capacitive mismatch including parasitic capacitors. The validity of the admittance model is proved by comparing between the admittance model and the measured data. At the end, the distortion in the frequency response curve measured by a capacitive sensor is analyzed and it is concluded that the admittance of the actuator is the main cause of this distortion.

In the design of a digital current controller for a 3-phase (3/spl phi/) voltage-source (VS) PWM power converter, its conventional model, i.e., stationary or synchronous reference frame model, is used in obtaining its discretized version. It introduces, however, inherent errors since the following practical problems are not taken into consideration: the characteristics of the space vector-based pulsewidth modulation (SVPWM) and the time delays in the process of sampling and computation. In this paper, the new hybrid reference frame model of the 3/spl phi/ VS PWM converter is proposed considering these problems. In addition, the direct digital current controller based on this model is designed without any prediction or extrapolation algorithm to compensate the time delay. So the control algorithm is made very simple. It represents no steady-state error in input current control and has the optimized transient responses. The validity of the proposed algorithm is proved by computer simulation results.