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Hot extrusion is a promising method for producing high-performance thermoelectric bismuth telluride alloys because of its ability to create textured microstructures. However, hot extrusion is less favourable for scaling-up because of temperature and strain gradients along the radial direction, and only -textured thermoelectric legs can be obtained because of the fibre-like texture. We suggest a way to overcome these disadvantages by implementing an additional spark plasma sintering process on a stack of extrudates. Using this combined process, we demonstrate the fabrication of 12 × 15 × 13 mm3 p-type (Bi0.2Sb0.8)2Te3 samples from extrudates that had originally been 3 mm in diameter. The evolution of sheet-like texture revealed by SEM, XRD, and EBSD allows us to obtain both - and -textured thermoelectric legs from a single specimen that are desirable for low- and high-temperature applications, respectively. Our results demonstrate the combined method as an industry-friendly process for fabricating high-performance thermoelectric materials.

Incorporating different wavelength (400 to 1000nm) LEDs, photoplethysmography (PPG) sensors allow wearable devices to monitor various health parameters such as heart rate (HR), oxygen saturation (SpO 2 ), and blood pressure (BP). Nowadays, PPG sensing technology at the wrist is well established. To cope with the large degree of motion turbulence presented at the wrist, PPG sensors use Green (Gr) LEDs together with multiple photodiodes (PD), and they are driven by wide-dynamic-range (DR) current-sensing front-ends [1]. It is attractive to use a near-infra-red (nIR) PPG sensor in a True Wireless Stereo (TWS), as the ear provides the best site to measure heart rhythm (more blood flow, constant distance from the heart, and less motion than at the finger or wrist). However, TWS requires a PPG sensor that is more stringent on size and power consumption (shown in Fig. 28.2.1). A promising solution [2, 3] is integrating an array of PDs with an ADC to dramatically reduce power while also providing monolithic integration. However, the limited DR (

The electrical resistance of a thermoelectric module is an important parameter as well as the thermoelectric figure-of-merit for the application of both waste energy harvesters and solid-state cooling devices. High resistance causes energy dissipation through Joule heating, leading to the degradation of the device's generating or cooling performance. Therefore, it is highly desirable to reduce the electric resistivity of the thermoelectric materials. Here, we report a hot extrusion technique to fabricate p-type bismuth antimony tellurides that has low electrical resistivity. Extrusion is a promising tool to fabricate a fiber-like texture of the microstructure, where the 001 normal vector of grains is pointing perpendicular to the extrusion direction. Such a textured microstructure can enhance the mobility of electrical carriers along the extrusion direction due to the anisotropic nature of electrical transport in bismuth telluride-based alloys. Beyond bismuth telluride-based thermoelectric materials, we believe that our result will offer a simple tool to manipulate physical properties of any two-dimensional, layered materials by controlling microstructure.

Volatile N-Nitrosamines (NAs), including N-nitrosodimethylamine (NDMA), an emerging contaminant in drinking water, have been reported to induce cancer in animal studies. This study aims to investigate the regional and seasonal distributions of the concentrations of NDMA, one of the most commonly found NAs with high carcinogenicity, in municipal tap water in Korea. NDMA in water samples was quantitatively determined using high-performance liquid chromatography-fluorescence detection (HPLC-FLD) as a 5-dimethylamino-1-naphthalenesulfonyl (dansyl) derivative after optimization to dry the SPE adsorbent and remove dimethylamine prior to derivatization. Tap water samples were collected from 41 sites in Korea, each of which was visited once in summer and once in winter. The average (&plusmn, standard deviation) NDMA concentration among all the sites was 46.6 (&plusmn, 22.7) ng/L, ranging from &lt, 0.13 to 80.7 ng/L. Significant NDMA differences in the regions, excluding the Jeju region, were not found, whereas the average NDMA concentration was statistically higher in winter than in summer. A multiple regression analysis for the entire data set indicated a negative relationship between NDMA concentration and water temperature. High levels of NDMA in Korea may pose excessive cancer risks from the consumption of such drinking water.

We propose an analog delay line (ADL) that adopts a current-splitting method (CSM) to reduce power consumption. The proposed ADL employs a pipelined sample-and-hold architecture and includes a buffer in the analog memory cell to prevent a charge sharing problem. The CSM reduces power consumption without distorting the sampled data by dividing the current source of the buffer into a holding current source and a buffering current source, which are, respectively, located inside and outside of the analog memory cell. The simulated power consumption of the proposed ADL without and with the CSM is 1080 and $90~{\mu }\text{W}$ , respectively, indicating that the CSM reduces power consumption by 91.7%. The proposed ADL was fabricated using a 0.18- ${\mu }\text{m}$ CMOS process with a 1.8-V supply voltage and occupies an active area of $120 \times 140~{ \mu }\text{m}^{ 2}$ . The sampling capacitor in the analog memory cell was implemented with MOS capacitors instead of metal-insulator-metal capacitors, resulting in an area per unit delay of the proposed ADL of only $600~{ \mu }\text{m}^{ 2}$ , which is much smaller than that in prior works. The measurement results show that the delay of the proposed ADL is accurately controlled from 25 to 475 ns with a unit delay step of 25 ns at a sampling frequency of 40 MHz.

Precise control of carrier density is essential to synthesize high-performance thermoelectric materials. Doping by impurities is often frustrated in n-type Bi2Te3 alloys by incomplete activation, bipolar doping, the formation of secondary phases, and prevailing intrinsic point defects such as vacancies. This weakens the reproducibility of synthesis processes and reduces the long-term reliability of material's performance, hence aging. Here, we explore an impurity-free doping technique to synthesize n-type bismuth tellurium selenides, combining a cold deformation and a hot extrusion. The cold deformation enables controlling the electron density in the range of ∼1019/cm3 via the formation of intrinsic point defects, and the hot extrusion allows texturing the microstructure to enhance the electrical conductivity, hence a large power factor of >5 × 10−3 W-m−1-K−2. We confirm that our process is very reproducible, and the properties of the samples are stable without aging even after thermal stresses. Using this method, we can decouple the relationship between bandgap, carrier density, and composition to improve the high-temperature thermoelectric property. Moreover, we demonstrate the fabrication of high-performance thermoelectric materials from low-graded, raw materials by modifying the degree of the mechanical deformation to reach an optimum carrier density. Our work provides a promising approach to synthesizing n-type thermoelectric materials in the reproducible and adaptable way.

This paper proposes an analog front-end (AFE) IC using a multiple-frequency driving method (MFDM). The proposed AFE IC achieves a high signal-to-noise ratio (SNR) by using an external noise spectrum and locating the frequencies of the excitation signals in low-noise regions. In addition, it employs the MFDM to increase the frame rate by simultaneously sending excitation signals having multiple frequencies to the touch screen panel (TSP). The proposed AFE IC extracts the coordinates of the finger as well as the coordinates, pressure, and tilt angle of the active stylus with the force gauge and gyro sensor. The proposed AFE IC and active stylus were fabricated in a 0.13- $\mu \text{m}$ standard CMOS process. The measurement results show that the proposed AFE IC achieves a frame rate of 3.9 kHz, and SNRs of 61.0 and 50.1 dB when a finger and active stylus are used, respectively. In addition, the pressure and tilt angle of the active stylus are expressed with 6-bit resolution. A capacitive touch system with the proposed AFE IC is demonstrated with a 65-in $104\times 64$ TSP using ten fingers and the active stylus with the pressure and tilt angle.

We employed a hot rolling process to modulate the n-type Bi2Te2.82Se0.18 microstructure. The as-quenched Bi2Te2.82Se0.18 ingot was hot-rolled immediately after heating at 773 K for 1 h. The reduction ratio in the hot rolling process was controlled by changing the rolling gap in a range from 2 mm to 5 mm. With the increase in reduction ratio, the (00 l) planes of Bi2Te2.82Se0.18, which have a higher carrier mobility, were more aligned parallel to the rolling direction and grain refinement was accelerated. Such changes in structural properties led to a drastic enhancement in carrier mobility and increased electron concentration. Consequently, the electrical conductivity of Bi2Te2.82Se0.18 was enhanced by the hot rolling process.

A concentrating photovoltaic (CPV) cell exhibits the highest conversion efficiency among any solar cells. However, the further enhancement of the CPV efficiency is strongly limited by the heat generation at high solar concentrations. Here, we demonstrate a concentrating photovoltaic/thermoelectric hybrid generator using a single-junction, GaAs-based solar cell and a conventional thermoelectric module as a model system. Our hybrid generator gives rise to the conversion efficiency larger than the single CPV cell by ~3% at the solar concentration of 50 suns. Controlling thermal flow in the hybrid generator and the Peltier cooling effect is the key to achieving high efficiency. Our result provides a framework for designing a highly-efficient hybrid generator using both photo-electric and photo-thermal effects for the clean-energy production.

This paper presents a low-noise amplifier (LNA) using attenuation-adaptive noise control (AANC) for ultrasound imaging systems. The proposed AANC reduces unnecessary power consumption of the LNA, which arises from useless noise floor, by controlling the noise floor of the LNA with respect to the attenuation of the ultrasound. In addition, a current feedback amplifier with a source-degenerated input stage reduces variations of the bandwidth and the closed loop gain, which are caused by the AANC. The proposed LNA was fabricated using a 0.18-[Formula: see text] CMOS process. The input-referred voltage noise density of the fabricated LNA is 1.01 [Formula: see text] at the frequency of 5 MHz. The second harmonic distortion is -53.5 dB when the input signal frequency is 5 MHz and the output voltage swing is 2 [Formula: see text]. The power consumption of the LNA using the AANC is 16.2 mW at the supply voltage of 1.8 V, which is reduced to 64% of that without using the AANC. The noise efficiency factor (NEF) of the proposed LNA is 3.69, to our knowledge, which is the lowest NEF compared with previous LNAs for ultrasound imaging.

This paper proposes a capacitive touch sensing system (CTSS) using an adaptive chopper stabilization (ACS) method to achieve high noise immunity. The proposed ACS method quickly detects and adaptively filters out external noises, thereby achieving high noise immunity in the proposed CTSS. To verify the proposed ACS method, a readout integrated circuit (ROIC) was fabricated using a 0.35- $\mu \text{m}$ CMOS process technology with 18 V high-voltage devices and was measured using a 46-in capacitive touch sensor (CTS). When no external noises are induced into the CTS, the measured signal-to-noise ratio (SNR) of the ROIC is 45.8 dB at a reporting rate of 120 Hz. When external noises are induced into the CTS, the measured SNR of the ROIC using the ACS method is 44.5 dB, which is improved by 22.0 dB compared with the SNR achieved without using the ACS method. Therefore, the proposed ACS method effectively eliminates external noises induced into the CTS of the CTSS.

Flexible thermoelectric modules (TEMs) are often built with a polymer filler as structural support. However, the filler may serve as a thermal bypass, leading to reduced temperature difference across a TEM and degradation of the output. Herein, we present flexible TEMs made of porous PDMS fillers and Bi2Te3-based thermoelectric legs. The heat conduction through the filler is suppressed by leveraging the low thermal conductivity of porous PDMS (0.08 W/m∙K), leading to an increase in the temperature difference across the TEMs. The porous PDMS TEM exhibits 23% enhanced power density and a figure of merit (ZT) of 0.75 around the room temperature. Lastly, the efficacy of the porous PDMS TEM is demonstrated by testing the TEMs with body heat. Our approach would offer a promising insight into the flexible TEM designs.

The thermoelectric figure-of-merit (zT) is a general standard used to evaluate the performance of thermoelectric materials. However, the performance of thermoelectric devices is largely affected by other properties such as electrical conductivity, thermal conductivity, and the power factor, depending on applications and boundary conditions. Therefore, it is beneficial to have a comprehensive map where the full range of thermoelectric properties are presented to design a high performance thermoelectric module optimized for any customized applications. In this study, we explore the thermoelectric properties of the n-type (1-x)Bi2Te3-xBi2Se3 alloys from x = 0.04 to x = 0.20 with various SbI3 doping levels. We used a hot extrusion technique to obtain a textured microstructure of our specimens to take advantage of their strong anisotropic nature. The SbI3 donor dopant enabled the precise control of electron density in the range of ∼1019 cm−3. Using this process, we constructed a thermoelectric property map as a function of the composition of the bismuth tellurium selenides and doping levels, to provide guidance on designing high performance thermoelectric modules for various applications.

Estimating the nonlinear seismic response of structure in earthquake engineering is important. Nonlinear static analysis is a typical method, and a variety of methods and techniques for estimating the stiffness of structural system at a certain analysis stage have been introduced and used in numerical structural analysis. On the other hand, such methods have many difficulties in practical usage because they use time-consuming iterative methods or simplified algorithms for calculating the structural stiffness at specific points in the time of nonlinear static analysis. For this reason, this study suggests an accurate and effective method for estimating the stiffness of a structure in nonlinear static analysis. For this goal, existing theories of an incremental step-by-step solution was investigated first. Subsequently, an algorithm available for calculating the precise stiffness of a structural system, each element of which has a bilinear material model, was developed based on the investigated methods. Finally, a computer program, sNs, was developed with the algorithm used.

Microbial forensics, exploiting bacteria, archaea, and eukaryotes, has been considered as one of the primary fields to trace the postmortem interval from the decaying cadavers. On the other hand, there remain several challenges of laboratory-based analysis for prediction of postmortem interval, including long-time measurement, complicated measuring procedure, and bacterial growth while carrying samples from the scene. Herein, we introduce the Smart Forensic Kit, which consists of a highly sensitive colorimetric gas sensor, a quality control algorithm, and a smartphone-based analysis method, to quantify the bacterial-derived ammonia gas in real-time. As a result, the estimation system of the postmortem interval has a superior selectivity to the ammonia gas with a detection limit of 38.7 ppb, response linearity to the target bacteria (Escherichia coli, Pseudomonas aeruginosa, and Pseudomonas putida), and short measuring time (10 min) with the maximum predicted postmortem interval from the mouse carcass (168 h). Furthermore, thanks to measuring the postmortem interval within 10 min, the negligible increase rate of bacterial concentration was observed. Consequently, the results reflected a high correlation between the ammonia gas emitted from bacteria and the postmortem interval so that we believe the Smart Forensic Kit will be applied for tracing down the decomposition of the cadavers in the near future.

Recently, the free form buildings are constructed frequently. Exterior and interior components of these buildings have the free cross-section and a curved shape. So, There are many usages of classical finite element having tapered section and free-style shape. Some general commercial applications like ETABS, SAP2000, MIDAS are usually used for the safety evaluation of the free form structures. However, there are some limits in the accuracy of structural analysis and the length of analysis time because a very complicated finite element mesh have to be used. Therefore, In this study, a pre and post program module was developed to take advantage of general 3-D curved beam element which has a free-style curved shape and mathematical backgrounds. Pre-post processing module has been developed in this study was developed to control the curvature of the curved members by the NURBS control points. As a result, fast geometric modeling than was possible commercial applications. In addition, realistic depiction of the shape and behavior patterns were possible because of the free-form building allows visual check of the free form.

Ammonia borane (NH 3 BH 3 ), as a source material for energy generation and hydrogen storage, has attracted growing interest due to its high hydrogen content. We have investigated the synthesis of ammonia borane from diborane (B 2 H 6 ) and ammonia (NH 3 ) utilizing a low-temperature process. From our results, a maximum synthetic yield of 92.2% was obtained, for an ammonia borane complex of 0.35 M. The diammoniate diborane (DADB) was detected in about 5–10 mol% within the solid ammonia borane by solid-state 11 B-NMR analysis. The synthesized solid ammonia borane products were studied to characterize hydrogen release upon thermal dehydrogenation.

Thermoelectric devices have attracted a great attention for renewable energy harvesters and solid-state coolers. For practical applications, the mechanical properties of thermoelectric materials become critical for the device reliability, a persistent performance with a long time and high operation cycles. Bi–Te based single-crystals, mostly used in commercial thermoelectric devices, are intrinsically brittle with weak van der Waals bonding, often leading to device failures such as crack and debonding during fabrication and operation. Thus, it is highly desirable to enhance the mechanical property of Bi–Te based alloys as well as the thermoelectric property. Here, we investigate the effect of B 4 C nanoparticles (less than 0.5 wt%) dispersed in p -type Bi 0.4 Sb 1.6 Te 3 matrix on the mechanical properties. X-ray diffraction (XRD) result confirms that B 4 C-dispersed Bi 0.4 Sb 1.6 Te 3 has a single phase. We observe that the grain size of Bi 0.4 Sb 1.6 Te 3 becomes decreased with the B 4 C nanoparticle concentration by electron backscatter diffraction (EBSD) technique. Hardness, Young’s modulus, and flexural strength of B 4 C-dispersed Bi 0.4 Sb 1.6 Te 3 are enhanced, compared to the B 4 C-free Bi 0.4 Sb 1.6 Te 3 polycrystals. On the other hand, the thermoelectric figure-of-merit of B 4 C-dispersed Bi 0.4 Sb 1.6 Te 3 is almost identical to that of the pure Bi 0.4 Sb 1.6 Te 3 . Such enhancements of the mechanical properties of the B 4 C-dispersed Bi 0.4 Sb 1.6 Te 3 are attributed to the grain boundary hardening and second-phase hardening. Beyond thermoelectric materials, our result implies that the grain refinement by nanoparticle dispersion is a simple and promising way to strengthen the mechanical properties of other brittle materials with layered structure.

As the demand for interactive displays continues to increase, capacitive touch systems (CTSs) with stylus-based drawing have become indispensable [1–4]. Passive styli are widely used because of their low-cost implementation, but have low SNR and limited drawing expressions [1]. Active styli have gained interest to solve these problems [4]. The pressure of an active stylus can be expressed using a pressure-to-capacitance transducer [3,4], but the tilt angle has not been reported yet. In addition, analog front-end (AFE) ICs with high frame rates are in demand in response to the fast movements of finger and active styli. Conventional AFE ICs adopt a parallel driving method (PDM) to achieve high SNR, but suffer from low frame rates because the number of rows and columns of the driving matrix increases with the number of TX electrodes [3]. In this paper, an AFE IC with high frame rate using a multiple-frequency driving method (MFDM) is proposed for response to fast movements of fingers and active styli, while expressing both the pressure and tilt angle of the active stylus.

Ammonia borane (), as a source material for energy generation and hydrogen storage, has attracted growing interest due to its high hydrogen content. We have investigated the synthesis of ammonia borane from sodium borohydride () and ammonium chloride () utilizing a low-temperature process. From our results, we obtained a maximum synthetic yield of 98.2% of ammonia borane complex. The diammoniate diborane (DADB) was detected in about 5~10mol% with in the solid ammonia borane by solid-state -NMR analysis. The synthesized solid ammonia borane products were studied to characterize hydrogen release upon thermal dehydrogenation.

Chronic pain caused by myofascial pain syndrome (MPS) results in generalized and debilitating conditions. Trigger-point injection (TPI) is the mainstay of MPS management to reduce acute and localized pain. Other adjunctive intervention to modulate the central pain pathway might be helpful if they are combined with TPI. Transcranial direct-current stimulation (tDCS), which is a form of neurostimulation, has been reported to be safe and effective in treating chronic pain by changing cortical excitability.To determine whether there is an additional effect of tDCS and TPI to reduce pain in patients with MPS.Twenty-one patients with newly diagnosed MPS of shoulder girdle muscles.Patients were randomly assigned into 1 of 3 groups (2 active and 1 sham stimulation groups) and received TPI. Immediately after TPI, tDCS (2 mA for 20 minutes on 5 consecutive days) was administered. For the active stimulation groups, tDCS was applied over 2 different locations (primary motor cortex and dorsolateral prefrontal cortex [DLPFC]).Visual analogue scale (VAS), Pain Threshold Test, and short form of the McGill Pain Questionnaire were measured before and immediately after stimulation for 5 consecutive days.The mean VAS values were decreased in all three groups after 5 days. There was a significant change between before and after stimulation only in the DLPFC group. The significant change in the mean VAS value was shown from after the second stimulation session (p=0.031), and this remained significant until the last stimulation session (p=0.027).This study suggests that tDCS over DLPFC may have additional effects with TPI to reduce pain in patients with MPS. tDCS over DLPFC can be used to reverse central pain pathway by modulating cortical plasticity.

A structural model consists of many types of finite elements, such as truss, beam, plate, shell and solid element, and so on. With the aid of commercial computer programs, field engineers comfortably use these finite elements at the same time for the modelling and analysis of real structure in their new projects. However, it is still difficult to model the connections and interfaces between different types of finite elements because of mutually ill-matched node numbers and degrees of freedom(d.o.f). To settle these problems, Many researchers studied and proposed various solution methods in literatures on FEA(Finite Element Analysis) and the use of transition elements is considered as one of the solutions. This pater presents an isoparametric formulation for three dimensional transition finite element, especially the solid-flat shell transition element. The proposed solid-flat shell transition element is composed of the solid element with 8 nodes, 3 d.o.f and the flat shell element with 4 nodes, 6 d.o.f for the simple formula derivation and the usefulness of practical applications. Basic theories for solid element and flat shell element are studied at first and a possible method for realizing the solid-flat shell transition element is suggested. On the basis of these theoretical backgrounds, the formula which calculates the stiffness matrix of the solid-flat shell transition element is derived in detail and an algorithm available for computer programming is investigated lastly.

Isothermal vapor–liquid equilibrium (VLE) data were measured for the binary systems of octafluoropropane + octafluorocyclobutane and hexafluoropropylene oxide + octafluorocyclobutane system at the ...

In this work, p-type 20%Bi2Te3–80%Sb2Te3 bulk thermoelectric (TE) materials were prepared by mechanical deformation (MD) of pre-melted ingot and by mechanical alloying (MA) of elemental Bi, Sb, and Te granules followed by cold-pressing. The dependence on annealing time of changes of microstructure and TE properties of the prepared samples, including Seebeck coefficient, electrical resistivity, thermal conductivity, and figure-of-merit, was investigated. For both samples, saturation of the Seebeck coefficient and electrical resistivity were observed after annealing for 1 h at 380°C. It is suggested that energy stored in samples prepared by both MA and MD facilitated their recrystallization within short annealing times. The 20%Bi2Te3–80%Sb2Te3 sample prepared by MA followed by heat treatment had higher a Seebeck coefficient and electrical resistivity than specimens fabricated by MD. Maximum figures-of-merit of 3.00 × 10−3/K and 2.85 × 10−3/K were achieved for samples prepared by MA and MD, respectively.

NCW is a new operational concept for modern warfare to improve the ability to conduct combat by connecting command and control system via network. To realize NCW integrating information sharing system between multiple platforms, CDL is considered as a key component for high-speed transmission of ISR data. Accordingly, further studies to enhance the performance of CDL are being performed around the world, and our government has also developed self-reliant CDL, MPI-CDL. However, the maximum data rate and networking performance of current CDL still fall short of the objective to enable multiple systems to share the large ISR data. Therefore, in this paper, we analyze the development flow and international technical trends of CDL, and present an approach for enhancing data rate and networking capacity of the next generation CDL. 논문 14-39C-03-01 Korea Information and Communications Society '14-03 Vol.39C No.03 http://dx.doi.org/10.7840/kics.2014.39C.3.209 209 ※ 본 연구는 2013년도 삼성탈레스(주)의 재원을 지원 받아 수행되었습니다. ° First Author and Corresponding Author : 성균관대학교 정보통신대학 통신시스템 연구실, sylpead@gmail.com, 학생회원 * 성균관대학교 정보통신대학 통신시스템 연구실, azaa@skku.edu, 학생회원, lyky77@skku.edu, 학생회원, hjchoi1@skku.edu, 종신회원 ** 삼성탈레스, dh84.lee@samsung.com, 정회원, sj100jung@samsung.com, 정회원 논문번호:KICS2013-10-439, Received October 11, 2013; Reviewed November 6, 2013; Accepted February 21, 2014 The Journal of Korea Information and Communications Society '14-03 Vol.39C No.03

Sung-Jin Jung Min-Sup LeeAbstractIn this study, we studied how to perform the structural analysis which need a large-capacity flash memory with the computerprogram when the flash memory storage of a personal computer has no enough room for the analysis of structure. As one of thesolutions of this problem, the blocking method of stiffness matrix, which is a method that stiffness matrix is divided by a few blocks and each block is sequentially used for the calculation of matrix decomposition, is proposed and an algorithm available incomputer program is derived on the method. Finally, A structural analysis program (sNs) based on this study is developed and the correctness and efficiency of the algorithm is founded through some examples which are fundamental in structural analysis.Keywords : Structural analysis, Massive matrix decomposition, Blocking method, Stiffness matrix, Algorithm, Structural analysis program

Multi-roofed historic wooden building 'connection' and 'special proportion' of the load according to the delivery system may be different. Layer and the layer again, and that there is a special proportional single layer than building Multi-roofed historic wooden building will be the reason for severe deformation. In this paper, we present a Multi-roofed historic wooden building in Korea in connection with the special classified on the basis of proportional type, susceptible parts to organized the structure, and the techniques used to reinforcement the study aims to. As a result, depending on the type of connection that specific proportion and was able to find similarities and differences.

Objective: To identify baseline risk factors associated with hemiplegic shoulder pain during the first 6 months after a stroke and to investigate changes in these risk factors over time. Design: Longitudinal observational study. Patients: A total of 94 patients with first-ever unilateral stroke lesion within 1 month after stroke. Methods: Clinical, radiological and sonographic evaluations were performed at baseline. Hemiplegic shoulder pain was assessed at 1, 3 and 6 months post-stroke. Associations between baseline factors and hemiplegic shoulder pain during the first 6 months and hemiplegic shoulder pain at 1, 3 and 6 months poststroke were analysed. Results: Poor arm motor function, indicated by a poor National Institutes of Health Stroke Scale item 5 score (odds ratio (OR) = 3.0; 95% confidence interval (CI) = 1.1–7.7) and the presence of supraspinatus tendon pathology (OR = 4.2; 95% CI = 1.4–12.9), were associated with hemiplegic shoulder pain. While patients with adhesive capsulitis, glenohumeral subluxation, or long head of biceps tendon effusion showed a higher prevalence of hemiplegic shoulder pain at 1 month after stroke, those with supraspinatus tendon pathology showed a higher prevalence at 3 and 6 months. Conclusion: Patients at high risk of hemiplegic shoulder pain with severe arm paralysis and supraspinatus tendon pathology require more careful attention during the rehabilitation period.

A high-voltage (HV) switch is proposed which adopts the floating control circuit to reduce area by removing the passive components and reducing the number of laterally diffused metal–oxide semiconductor field effects (LDMOSFETs). The proposed HV switch consists of three LDMOSFETs and three MOSFETs without any passive components. In addition, the routing complexity of the control signals is greatly reduced by sharing all control signals in the array of switches. The proposed HV switch is fabricated using a 0.18 μm CMOS process with 50 V devices and occupies 85 × 65 μm2. The measured off-isolation is −53 dB.

The effects of mechanical deformation and subsequent annealing on the thermoelectric properties and microstructure have been investigated for p-type (Bi0.25Sb0.75)2Te3 alloys prepared by melting followed by quenching. The mechanically deformed pellets were prepared by repetition of cold-pressing of quenched samples at room temperature. Cold-pressed pellets were then annealed at 300°C in vacuum, and the thermoelectric properties and microstructure were traced through the course of the heat treatment. For the heavily deformed samples, the Seebeck coefficient rapidly increased at the very early stage of annealing and did not change as the annealing time increased, due to recrystallization of a new δ-phase which equilibrated at the annealing temperature of 300°C (δ300-phase). At the initial stage of annealing (recovery stage), the electrical resistivity sharply increased, probably due to the interaction of antistructural defects with vacancies produced during the cold-pressing treatment. However, for the lightly deformed samples, recrystallization occurred only at some portion of the grain boundaries, and the newly generated δ300-phase slowly replaced the original, as-solidified δingot-phase.

This paper presents an integrated ultrasound chip (IUC), which adopts a three-side buttable architecture to integrate a large number of capacitive micromachined ultrasonic transducers (CMUTs) and a reconfigurable 16 × 16 transceiver array to configure the transmitting and receiving patterns of a CMUT array. The IUC was fabricated using a silicon-based MEMS process and a 0.35- μm CMOS process with 120 V devices. The transmitting and receiving patterns were controlled to optimize the image SNR and frame rate for a given target image. The proposed area-efficient high-voltage level shifter and digital pulse width control scheme were adopted to implement the reconfigurable transceiver array. Furthermore, a static sequential access memory block was implemented to reduce the loading time of the configuration data, which are used to control the IUC. For a 2 × 8 IUC array with a data rate of 400 Mb/s, the data-loading time was reduced from 123.2 to 1 μs. The image of a spring with a diameter of 1 mm was successfully acquired using the proposed IUC with fully transmitting and receiving array.