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The reduction unit is one of the most important components in railway cars, due to the transmission of torque from the motor to the wheels. Faulty reduction gears in high-speed trains result from excessive wear on the gear or damage to the gear. These types of gear defects have a significant effect on high-speed rail operation and safety; thus, a diagnosis system for the reduction unit is needed. Vibration diagnosis technology is one of the most effective diagnostics. In this paper, the vibration parameters of a reduction unit were evaluated during a driving-gear test and a full-vehicle test, using kurtosis and the crest factor. These tests were performed under normal operating conditions; a specimen tester was used to diagnose problems in defective gears.

The 5-HT6R has been considered as an attractive therapeutic target in the brain due to its exclusive expression in the brain. However, the mechanistic linkage between 5-HT6Rs and brain functions remains poorly understood. Here, we examined the effects of 5-HT6R-mediated cell morphological changes using immunocytochemistry, Western blot, and live-cell imaging assays. Our results showed that the activation of 5-HT6Rs caused morphological changes and increased cell surface area in HEK293 cells expressing 5-HT6Rs. Treatment with 5-HT specifically increased RhoA-GTP activity without affecting other Rho family proteins, such as Rac1 and Cdc42. Furthermore, live-cell imaging in hippocampal neurons revealed that activation of 5-HT6Rs using a selective agonist, ST1936, increased the density and size of dendritic protrusions along with the activation of RhoA-GTP activity and that both effects were blocked by pretreatment with a selective 5-HT6R antagonist, SB258585. Taken together, our results show that 5-HT6R plays an important role in the regulation of cell morphology via a RhoA-dependent pathway in mammalian cell lines and primary neurons.

The reduction unit is one of the most important components for railway vehicles because the torque of the motor must be transmitted to the wheels of the vehicle by the reduction unit. The faults in the reduction units of high-speed trains are caused by damage such as gear, fatigue. These have serious impacts on safety of the train during operation. To address this development of a system for monitoring, fault diagnosis of the reduction unit is needed to keep the vehicle running safely. Before that can be accomplished, it is most important to understand the vibration characteristics of the reduction unit in a normal state. Vibration diagnosis technology using characteristic-analysis of vibration waveform and frequency is known to be the most effective method for fault diagnosis. In this paper, we analyzed the vibration characteristics of the reduction units two Korean high-speed trains (KTX and KTX II), under normal conditions, by two test methods (driving gear test, full-vehicle test).

Relocation mechanisms of the circulating tumor cells (CTCs) from the primary site to the secondary site through the blood vessel network cause tumor metastasis. Despite of the importance to diagnose the cancer metastasis by CTCs, still it is formidable challenge to use in the clinical purpose because of the rarity and the heterogeneity of CTCs in the cancer patient's peripheral blood sample. In this study we have developed magnetic force gradient based microfluidic chip (Mag-Gradient Chip) for isolating the total number of CTCs in the sample and characterizing the state of CTCs simultaneously with respect to the epithelial cell adhesion molecule (EpCAM) expression level. We have synthesized magnetic nanoparticles (MNPs) using hydrothermal method and functionalized anti-EpCAM on their surface for the specific binding with CTCs. The Mag-Gradient Chip designed to isolate and classify the CTCs by isolating at the different location in the chip using magnetic force differences depending on the EpCAM expression level. We observed 95.7% of EpCAM positive and 79.3% of EpCAM negative CTCs isolated in the Mag-Gradient Chip. At the same time, the 71.3% of isolated EpCAM positive CTCs were isolated at the first half area whereas the 76.9% of EpCAM negative CTCs were collected at the latter half area. The Mag-Gradient Chip can isolate the 3ml of heterogeneous CTCs sample in 1h with high isolating yield. The EpCAM expression level dose not means essential condition of the metastatic CTCs, but the Mag-Gradient Chip can shorten the date to diagnose the cancer metastasis in clinic.

While the demand for micro-energy harvesters (μEHs) is increasing (for seamless energy source in applications such as wireless sensor node), two major problems still obstruct versatile use of them. The first problem is the self-startup capability. Because many wireless sensor nodes are likely to be located where human-maintenance is difficult, starting them up manually can be as difficult as replacing the battery. Its realization has been difficult because μEHs must be able to turn itself on without any stored energy. Some previous works have reported such a function: some needed high voltage [1] or vibration [2] and one used a transformer as a starter [3]. The other problem is the maximum power point tracking (MPPT) capability. Because it is known that MPPT algorithms usually require considerable power consumption [4], using them in μEHs is impractical. This paper suggests a new boost converter architecture and MPPT control method which can bring μEH into practical use.

This is the first attempt to produce simultaneous surface current field from satellite altimeter data for the entire East Sea and to provide surface current information to users with formal description. It is possible to estimate surface geostrophic current field in near real-time because satellite altimeters and coastal tide gauges supply sea level data for the whole East Sea. Strength and location of the major currents and meso-scale eddies can be identified from the estimated surface geostrophic current field. The mean locations of major surface currents were explicated relative to topographic, ocean-surface and undersea features with schematic representation of surface circulation. In order to demonstrate the practical use of this surface current information, exemplary descriptions of annual, seasonal and monthly mean surface geostrophic current distributions were presented. In order to objectively classify surface circulation patterns in the East Sea, empirical orthogonal function (EOF) analysis was performed on the estimated 16-year (1993-2008) surface current data. The first mode was associated with intensification or weakening of the East Korea Warm Current (EKWC) flowing northward along the east coast of Korea and of the anti-cyclonic circulation southwest of Yamato Basin. The second mode was associated with meandering paths of the EKWC in the southern East Sea with wavelength of 300 km. The first and second modes had inter-annual variations. The East Sea surface circulation was classified as inertial boundary current pattern, Tsushima Warm Current pattern, meandering pattern, and Offshore Branch pattern by the time coefficient of the first two EOF modes.

The existing protocols proposed in network mobility (NEMO) environment can require many computational costs and can bring about a delay of binding update. To solve these problems, in this paper we propose an authentication protocol supporting secure seamless handover in NEMO environment. The proposed protocol can handle quickly mutual authentication between a mobile router (MR) and an access router (AR), which uses group key among ARs and a master key (MK) issuing from key issuing server (KIS) for reducing the time of binding update as much as possible. In performance, the proposed protocol can process quickly binding update with little computational cost comparison with the existing binding update protocols and it results in robustness against existing attacks.

This paper reports a label-free biosensor for the detection of DNA hybridization. The proposed biosensor measures the surface potential on oligonucleotide modified electrodes using a direct charge accumulation method. The sensor directly and repeatedly measures the charges induced in the working electrode, which correspond to intrinsic negative charges in immobilized molecules. The sensor achieves an improved signal-to-noise ratio (SNR), through the oversampling effect of accumulation for charges and the differential architecture. The sensor also shows stable, robust, and reproducible measurement independent of slight changes in the reference voltage, unlike previous ion-sensitive field effect transistors (ISFETs), providing the benefits of choosing a wide variety of reference electrode materials. The proposed device is integrated with working electrodes, a reference electrode and readout circuits into one package via a 0.35 μm complementary metal-oxide-semiconductor (CMOS) process. The sensor achieves a detectable range of 88.3 dB and a detection limit of 36 μV for surface potential. It is demonstrated that the sensor successfully achieves specific detection of oligonucleotide sequences derived from the H5N1 avian influenza virus. The experiments show a limit of detection of 100 pM and include a single-base mismatch test in 18-mer oligonucleotides.

The aim of this paper is to develop a framework of weather information services which is for processing contents and providing proper contents to new-media such as outdoor electronic display, DID (digital information display), and terrestrial multi-channel broadcasting, etc. By introducing the analysis of media use and perception science of human intelligence, the contents producing method to improve recognizing rate for weather information is provide and the layered framework of weather information services for new-media is designed. It integrates many different services to the framework. It can prevent duplicate investment for services and serve a major momentum to technical progress.

Heat pump systems for commercial building with variable refrigerant flow(VRF) are expanding a market due to high energy efficiency, lower maintenance cost and easy installation comparing with the conventional heat pump with the constant refrigerant flow. In general, heat pump systems degrade the energy efficiency in the extremely low temperature regions. In this study, VRF heat pump system with refrigerant heating is experimentally investigated to overcome the low heating performance in the extremely low temperature regions. VRF heat pump system with refrigerant heating is found out the sufficient heating performance in the -25 degree tem-perature condition comparing with the conventional heat pump system and is obtained more than 2,500 kPa high pressure in the evaporator at low temperature.Keywords:VRF(Variable Refrigerant Flow：냉매유량가변), Refrigerant heating(냉매 가열), Building Multi(빌딩 멀티), R410A(냉매 R410A), BLDC Inverter(BLDC 인버터), Burner(버너), Heat source(열원) †Corresponding author Tel.: +82-51-510-2455; fax: +82-51-582-6368 E-mail address: cheeky81@pusan.ac.kr

This paper describes a sensor for label-free, fully electrical detection of DNA hybridization based on capacitive changes in the electrode-electrolyte interface. The sensor measures capacitive changes in real time according to a charging-discharging principle that is limited by the hysteresis window. In addition, a novel autonomous searching technique, which exclusively monitors desorption-free hybridized electrodes among electrode arrays, enhances the performance of the sensor compared with conventional capacitive measurement. The sensor system achieves a detection range of 80 dB. The integrated circuit sensor is fabricated with a 0.35 μm CMOS process. The proposed sensor offers rapid, robust and inexpensive measurement of capacitance with highly integrated detection circuitry. It also facilitates quantitative evaluations of molecular densities on a chip with distinctive impedance variations by monitoring desorption-free hybridized electrodes. Our electrical biosensor has great potential for use with bio analytical tools and point-of-care diagnosis.

In this paper, we have investigated ultrahigh frequency nano-mechanical resonators, made of DWCNTs with various wall lengths, via classical molecular dynamics simulations. We have aimed our analysis on the frequency variations of these resonators with the DWCNT wall lengths. The results show that the variations can be well fitted by either the Pearson VII function when the resonant frequency of normalized by its maximum frequency is plotted as a function of the inner/outer wall length ratio L5/L10 for different values of the outer wall length L10, and the Gauss distribution function when the resonant frequency of normalized by its maximum frequency is plotted as a function of the outer/inner wall length ratio for different values of the inner wall length.

Most of air pollution in a metropolis is the result of exhaust gas emissions from automotive vehicles, and the world-wide regulation against environmental pollution is becoming more strict. Moreover the demand on development and supply of an environment-friendly automobile is increasing and the market share about that is expected to grow rapidly in this time of high oil price. The secondary batteries the most important component to store the electrical energy in hybrid electric vehicle. It needs to the higher power characteristics to emit the energy instantaneous. In this paper, we proposed the system to monitor reliably the charge and discharge states of the secondary batteries for hybrid electric vehicle. The material is about SW and HW module the software and hardware module mounted on the charge and discharge system and the monitoring system to control the charge and discharge performance effectively.

A method of the region extraction and recognition of a traffic light and speed sign board in the real road environment is proposed. Traffic light was recognized by using brightness and color information based on HSI color model. Speed sign board was extracted by measuring red intensity from the HSI color information We improve the recognition rate by performing an incline compensation of the speed sign for directions clockwise and counterclockwise. The proposed algorithm shows a robust recognition rate in the image sequence which includes traffic light and speed sign board.Keywords:Color Segmentation, Sign Recognition, Light Recognition, Template Matching 1. 서 론 * 오늘날 자동차의 보유량은 급격하게 증가하고 있고 이것에 비례하여 교통사고 역시 급격하게 증가하고 있다. 교통사고의 원인으로는 교통 혼잡, 운전자의 노령화, 운전자 계층의 다양화 등이 있다. 과거에는 교통사고 방지를 운전자 개인의 능력에만 의존했다면 현대에는 자동차와 기계, 전자, 통신, 제어, 인공지능 등 각종 첨단 기술을 접목시켜 운전자에게 부담을 덜어주어 운전 미숙에 대한 교통사고를 방지하기 위한 연구인 지능형 교통 시스템(ITS:Intelligent Trans-portation Systems)이 활발히 진행되고 있다. 이러한 지능형 교통 시스템 서비스 중 AVHS(Advanced Vehicle and Highway System)란 서비스는 차량에 교통상황, 장애물 인

A new Class-K* audio amplifier with high-power efficiency and high fidelity is integrated in a 0.35-μm CMOS process. It proposes a new topology connected Class-D amplifier with fast-switching charge-dump (FSCD) amplifier in parallel. The integration of the amplifier requires neither analog buffer amplifier nor a complex compensation circuit needed in hybrid audio amplifier (Class-K). The FSCD amplifier composed of comparators and switches works at a high-switching frequency in order to absorb the distortion caused by Class-D amplifier switching. Thus, this assists the audio amplifier to have good linearity under switching operation. With the proposed topology, the audio amplifier has a flat frequency response with - 3-dB bandwidth of 60 KHz and is capable of delivering up to 257 mW into 4.1-Ω load with maximum efficiency of 81%. A typical total harmonic distortion plus noise (THD+N) is less than 0.1% at the power level over 25 mW within the audio frequency range (20 Hz-20 kHz), and the minimum THD+N is 0.025% with the audio input frequency of 1 kHz at the output power of 114 mW.

Local hidden variable theory has been abandoned because it violates the Bell inequality. However, the Bell inequality does not tell us which assumption, either locality or reality or even both, should be discarded in local hidden variable theory. A recently proposed incompatibility theorem for Leggett-type nonlocal hidden variable theory provides some progress in addressing this question. We propose a very simple incompatibility theorem by inspecting the properties of the singlet state within Leggett-type nonlocal hidden variable theory and discuss the characteristics of the incompatibility.

A method of the region extraction and recognition of a speed sign in the real road environment is proposed. The region of speed sign is extracted by using color information and then numbers are segmented in the region. We improve the recognition rate by performing an incline compensation of the speed sign for directions clockwise and counterclockwise. In image sequences of the real road environment, a robust recognition results are achieved with speed signs at normal condition as well as inclined.

RF (resorcinol formaldehyde) organic aerogels were cost-effectively prepared by solvent exchange using acetone and then ambient drying of RF wet gels obtained from the sol–gel method of the starting solution of RF. The carbon aerogel electrodes for the capacitive deionization (CDI) process with high specific surface area (∼610 m2/g), high specific capacitance (∼220 F/g), high porosity (∼80%), low bulk density (∼0.50 g/cm3), and high electrical conductivity (∼13.2 S/cm) have been synthesized via pyrolyzing RF organic aerogels at 800°C in nitrogen atmosphere. The CDI unit system containing a pair of carbon aerogel electrodes showed the maximum ion removal efficiency when the 50 mg/L NaCl solution was recycled at the volume flow rate of 400 mL/min under the applied voltage in the range of 1.5–1.7 V. Under the optimum operating conditions of the CDI unit system, the NaCl removal efficiency of the CDI stack system composed of 6 unit cells was about 92.8% and 97.6% at 1.5 and 1.7 V, respectively. It was evaluated that the CDI process using carbon aerogel electrodes promised to be an effective technology for desalination.

A biosensor with an alternating current-driven control is realized for label-free detection of biomolecule. This sensor precisely measures the capacitive changes in the electrode-electrolyte interface after hybridization with complementary DNA targets. Conventional capacitive biosensors generally use the excitation method with double current-sources. However these sensors have limitations due to performance-based issues of the DC potential drift and offsets, as well as weakness against common-mode noises. In this paper, the proposed device includes differential electrode pairs that are located in a single current-source line with sensing circuits, which results in the elimination of the effect due to the current mismatch. The device also shows an improved signal-to-noise ratio. Additionally, the individual control of the switch controller in this device offers robust and reproducible measurement capabilities independent of the duty asymmetry and pre-charged initial offset voltage. The device is a hybrid sensor that has both working electrodes and readout circuitry in one-chip using a CMOS process. The prototype successfully demonstrated the specific detection of oligonucleotide sequences. The device consumes 2.34mW from a 3.3 V supply in a 0.35 µm CMOS process.

A self-contained cartridge and an integrated instrument for the automated molecular testing are described. The proposed cylindrical cartridge consists of multiple chambers containing all necessary reagents such as specimens, lysis, wash, and elution buffers. The system provides a chain of automatic processes for the molecular test of sample preparation, amplification, and detection. Sample preparation can be fully conducted inside the cartridge, which includes reagents mixing, nucleic acids capturing, wastes-out, and eluates collection. The system also implements the amplifying and detecting processes of the extracted DNA using the peltier heating and photometry scanner, respectively. All flow movements in the instrument are driven by pneumatic actuations of syringe/piston sets and valve controls based on the motor driving. The molecular tests in the system were evaluated clinically using Salmonella bacteria. The performance of the system was verified successfully by comparing with the results from commercial equipment. The system including the disposable cartridge has the potentials to be applicable for point-of-care testing of molecular diagnostics such as Polymerase Chain Reaction (PCR) or other amplification methods such as isothermal amplification, resulting in an early diagnosis of disease.

Backgrounds/Aims Discovery of new prognostic factors for cases in which the pancreatic cancer scoring and staging system does not result in a clear definition is imperative. We examined the role of Human AlkB homolog H5 (ALKBH5) as a prognostic marker for pancreatic cancer. Methods Patient data were extracted from the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA). The prognostic value of ALKBH5 was confirmed via analysis of ALKBH5 and other clinical factors, such as age, sex, and stage, using the time-dependent area under the curve (AUC) of Uno's C-index, the AUC value of the receiver operating characteristics (ROC) at three years, the Kaplan-Meier survival curve, and multivariate analysis. Results ALKBH5 showed excellent prognosis prediction in comparison with existing markers in the two independent cohorts (n=262). Kaplan-Meier survival analysis showed that ALKBH5 expression was positively associated with overall survival (log-rank test, ICGC, p=0.001; TCGA, p=0.01). Notably, comparison of C-index and AUC values in ROC analysis showed that ALKBH5 was associated with high C-index and AUC values compared with other clinical variables (C-index: ICGC, 0.621; TCGA, 0.614 and AUC at three years: ICGC, 0.609; TCGA, 0.558). Multivariate analysis demonstrated thatALKBH5 is an independent prognostic factor (ICGC, p=0.0123; TCGA, p

5-HT7 receptor (5-HT7R) is a promising target for the treatment of depression and neuropathic pain. 5-HT7R antagonists exhibited antidepressant effects, while the agonists produced strong anti-hyperalgesic effects. In our efforts to discover selective 5-HT7R antagonists or agonists, N-biphenylylmethyl 2-methoxyphenylpiperazinylalkanamides 1 were designed, synthesized, and biologically evaluated against 5-HT7R. Among the synthesized compounds, N-2'-chlorobiphenylylmethyl 2-methoxyphenylpiperazinylpentanamide 1-8 showed the best binding affinity with a Ki value of 8.69nM and it was verified as a novel antagonist according to functional assays. The compound 1-8 was very selective over 5-HT1DR, 5-HT2AR, 5-HT3R, 5-HT5AR and 5-HT6R and moderately selective over 5-HT1AR, 5-HT1BR and 5-HT2CR. The novel 5-HT7R antagonist 1-8 exhibited an antidepressant effect at a dose of 25mg/kg in the forced swimming test in mice and showed a U-shaped dose-response curve which typically appears in 5-HT7R antagonists such as SB-269970 and lurasidone.

We investigate the measurement-induced dephasing of a qubit coupled with a single-mode cavity in the vacuum limit. Dephasing of the qubit state takes place through the ntanglement of the qubit and the single probe photon sent to the cavity, while the cavity mode never occupies a photon. We find that the qubit state is dephased even if the cavity is always in the vacuum state. This dephasing is caused purely by the interaction between the qubit and the vacuum field. We also show that this vacuum-fluctuation-induced dephasing takes place much faster than the spontaneous decay of the qubit excited state, and therefore our prediction is observable in a real experiment., Comment: 6pages, 5 figures

Serotonin (5-HT) receptors of type 6 (5-HT6R) play important roles in mood, psychosis, and eating disorders. Recently, a growing number of studies support the use of 5-HT6R-targeting compounds as promising drug candidates for treating cognitive dysfunction associated with Alzheimer's disease. However, the mechanistic linkage between 5-HT6R and such functions remains poorly understood. By using yeast two-hybrid, GST pull-down, and co-immunoprecipitation assays, here we show that human 5-HT6R interacts with the light chain 1 (LC1) subunit of MAP1B protein (MAP1B-LC1), a classical microtubule-associated protein highly expressed in the brain. Functionally, we have found that expression of MAP1B-LC1 regulates serotonin signaling in a receptor subtype-specific manner, specifically controlling the activities of 5-HT6(R), but not those of 5-HT4R and 5-HT7R. In addition, we have demonstrated that MAP1B-LC1 increases the surface expression of 5-HT6R and decreases its endocytosis, suggesting that MAP1B-LC1 is involved in the desensitization and trafficking of 5-HT6R via a direct interaction. Together, we suggest that signal transduction pathways downstream of 5-HT6R are regulated by MAP1B, which might play a role in 5-HT6R-mediated signaling in the brain.

The 5-HT7 receptor (5-HT7 R) is a promising therapeutic target for the treatment of depression and neuropathic pain. The 5-HT7 R antagonist SB-269970 exhibited antidepressant-like activity, whereas systemic administration of the 5-HT7 R agonist AS-19 significantly inhibited mechanical hypersensitivity and thermal hyperalgesia. In our efforts to discover selective 5-HT7 R antagonists or agonists, aryl biphenyl-3-ylmethylpiperazines were designed, synthesized, and biologically evaluated against the 5-HT7 R. Among the synthesized compounds, 1-([2'-methoxy-(1,1'-biphenyl)-3-yl]methyl)-4-(2-methoxyphenyl)piperazine (28) was the best binder to the 5-HT7 R (pKi =7.83), and its antagonistic property was confirmed by functional assays. The selectivity profile of compound 28 was also recorded for the 5-HT7 R over other serotonin receptor subtypes, such as 5-HT1 R, 5-HT2 R, 5-HT3 R, and 5-HT6 R. In a molecular modeling study, the 2-methoxyphenyl moiety attached to the piperazine ring of compound 28 was proposed to be essential for the antagonistic function.

Plasmonic absorbers with optical cavity are fabricated using deposition of thin gold films on both sides of nanoporous anodic aluminum oxide (AAO) microcantilevers. Photothermal/opto-calorimetric responses of the microcantilevers are investigated with respect to various pore sizes and gold coating thicknesses. Photothermal/opto-calorimetric response of the AAO cantilever is significantly amplified when the thickness of the gold layer is at 40 nm due to scattering and trapping of infrared (IR) radiation in the gold nanomesh/AAO nanochannels/gold layer structure. Unlike previous photothermal IR spectroscopy of adsorbed molecules with a bimetallic AAO cantilever, the reversed IR spectra are obtained due to significantly amplified baseline photothermal signal and IR absorption of free molecules. Molecular detection sensitivity is enhanced by an order of magnitude compared with the previous photothermal IR spectroscopy of adsorbed molecules on a bimetallic AAO cantilever. The acetone vapor molecules are select...

Silicon devices based on impedance measurements offer label-free and direct electrical detection when used to quantify the hybridization of DNA molecules. They show rapid, robust, and inexpensive measurement and compatibility with commercial microfabrication technology. The real-time measurement of the impedance does not require the use of labeling molecules attached to the target DNA in optical and magnetic technology [1,2]. It also has the advantage of miniaturization for point-of-care (PoC) or on-site sensing applications, unlike the 3-electrode topology in electrochemical sensors [3]. Several studies have proposed capacitive biosensors that utilize a nonfaradaic process, which refers to transient currents charging a geometrical capacitor in an electrolyte-electrode interface [4]. Conventional capacitive biosensors using the excitation of the bidirectional current [5,6] can be implemented with a compact design, but they have several issues that degrade the sensitivity of the sensor, such as DC drift in the electrode caused by a charge imbalance, the electrolysis generated by DC voltage across the electrodes, the offset generated by pre-charged initial values, and weakness against common-mode noise. As a solution, we report a fully integrated capacitance-based biosensor that locates two electrodes differentially in a single current source.

We address the ultimate charge detection scheme with a quantum point contact. It is shown that a superposed input state is necessary to exploit the full sensitivity of a quantum point contact detector. The coherence of the input state provides an improvement in charge sensitivity, and this improvement is a result of the fundamental property of the scattering matrix. Further, a quantum-limited (maximally efficient) detection is possible by controlling the interference between the two output waves. Our scheme provides the ultimate sensitivity and efficiency of charge detection with a generic quantum point contact., Comment: 11 pages, 3 figures

We present a scheme for tuning two quantum point contacts as a quantum-limited charge detector. Based on the scattering matrix approach, we analyze a general condition of quantum-limited detection with a single-channel quantum detector possessing time-reversal symmetry. From this analysis we find that quantum-limited detection can be easily realized with two quantum point contacts connected in series, which is not possible if only a single quantum point contact is used. We also discuss the sensitivity enhancement due to multiple reflections of the two point contacts., Comment: 9 pages, 2 figures

This paper describes a label-free and fully electronic detection method of DNA hybridization, which is achieved through the use of a 16 × 8 microarray sensor in conjunction with a new type of impedance spectroscopy constructed with standard complementary metal-oxide-semiconductor (CMOS) technology. The impedance-based method is based on changes in the reactive capacitance and the charge-transfer resistance after hybridization with complementary DNA targets. In previously published label-free techniques, the measured capacitance presented unstable capacitive properties due to the parallel resistance that is not infinite and can cause a leakage by discharging the charge on the capacitor. This paper presents an impedance extraction method that uses excitation by triangular wave voltage, which enables a reliable measurement of both C and R producing a highly sensitive sensor with a stable operation independent of external variables. The system was fabricated in an industrial 0.35-μm 4-metal 2-poly CMOS process, integrating working electrodes and readout electronics into one chip. The integrated readout, which uses a parasitic insensitive integrator, achieves an enlarged detection range and improved noise performance. The maximum average relative variations of C and R are 31.5% and 68.6%, respectively, after hybridization with a 1 μM target DNA. The proposed sensor allows quantitative evaluation of the molecule densities on the chip with distinguishable variation in the impedance. This fully electronic microsystem has great potential for use with bioanalytical tools and point-of-care diagnosis.

This paper provides a complex band-pass filter (BPF) for low-IF conversion digital audio broadcasting (DAB) and terrestrial-digital multimedia broadcasting (T-DMB) tuner with I/Q gain and phase mismatch calibration. This calibration can be implemented in the first stage of complex BPF using feed-through resistor calibration scheme. The automatic tuning circuit with programmable clock is also presented. The measurement results show 1.536 MHz bandwidth with 2.048 MHz IF center frequency and 50 dB stop band attenuation at 0.7 MHz frequency offset. The in-band and out-band 3rd order intermodulation distortion (IMD3) are 55 and 60 dBc, respectively. After I/Q mismatch calibrating, 20 dB image rejection ratio (IRR) improvement is obtained from 38 dB to 58 dB in this work. The automatic tuning circuit guarantees less than +/- 4 % cut-off frequency variation covering the several clock requirements from demodulator ICs. The complex BPF is fabricated in 0.13 mum RF CMOS technology and consumes 9 mA with 1.2 V power supply.

A charge pump drive circuit for LED lighting is proposed. This circuit is realized with repeated use of a compact unit module consisted of a capacitor and diodes. The series-charge and parallel-discharge operation gives the efficiency better than the conventional converters with AC line input. This paper also shows how to minimize the number of modules for a given number of LEDs. A prototype implemented the charge pump drive circuit shows a maximum efficiency of 95% for 22 LEDs in series with the AC line voltage of 220 Vrms.

A fully on-chip CMOS VGA-based load- independent linear amplitude modulator is implemented for class E1, E2 power amplifiers of GSM/EDGE polar transmitter. By utilizing VGA-based 3-path architecture based on capacitor-free low-dropout linear regulator (LDO), the proposed circuit provides fast and stable operation at all-load conditions including open load when the battery varies from 3.4 V to 5.5 V. The small-signal bandwidth is wider than 5 MHz and the phase margin is bigger than 64deg at the worst-case-simulation condition. The circuit can stably drive output load-current of 0 to 1.6 A at a static bias-current of under 1 mA. The output voltage varies from 0.43 V to 3.2 V when the input reference-voltage VRAMP varies from 0.2 V to 1.5 V. The chip is fabricated in a TSMC 0.35 mum mixed-mode CMOS 2P 4M process and the size of pass transistor is 1.6 mm times 1 mm.

A fast switching charge dump assisted class-D audio amplifier is presented in this paper. To achieve high efficiency and high linearity, the Class-K* audio amplifier consists of the class D amplifier with high efficiency and the proposed charge dump amplifier with high linearity. The charge pump amplifier works at faster switching frequency than class D amplifier so as to compensate the distortion caused by switching of the class-D amplifier. The class-K* audio amplifier implemented in 0.35mum CMOS process shows -71.8 dB THD+N at 1 KHz and a maximum efficiency of 81% at an output power of 257 mW for 4.1Omega load.

A hybrid switching amplifier for dynamic power supply applications is presented. To achieve both high speed and high efficiency, a wideband buffered linear amplifier is combined with a hysteretic controlled switching amplifier. To obtain high linearity and reduce switching loss at low power levels where the switching amplifier is not needed, the linear amplifier supplies all load current with the switching one disabled. The novel two-quadrant linear amplifier as a voltage source for regulating the output voltage has very low output impedance of about 200 m Omega around the switching frequency, a high current-driving capability of maximum 220 mA and a bandwidth wider than 7 MHz. The hybrid amplifier can drive a circuit with an equivalent impedance of 7 Omega and supply a maximum output power of 1.1 W with a maximum efficiency of about 91%. Its output voltage ranges from 0.3 V to 2.9 V for a 3.3V supply. The chip is fabricated using only thick-oxide devices in a 0.13 um CMOS process and occupies an area of 3.9 mm2.

The current or voltage driving schemes are employed for pulse-amplitude modulation (PAM) in AMOLED displays. Current driving methods have advantages over voltage driving schemes including improvement of luminance uniformity at display panels and compensation of TFT characteristics at pixels. degrade the driving accuracy. This paper introduces a direct-type fast feedback current (DFFC) driver that offers fast settling time with good accuracy by comparing the data with the pixel current directly. An optimum compensation method for the feedback loop is suggested as well.

A UHF mobile single chip RFID reader is implemented in 0.18 mum CMOS process. Developed IC achieves DA output power of 3 dBm, OIP3 of 14.8 dBm, phase noise of -100 dBc/Hz at 100 kHz offset, noise figure of 35.5 dB for talk mode, 6.2 dB for listen before talk (LBT) mode, and current consumption of 108 mA from a 1.8 V supply. With an external PA, Tx output generates output power of 27 dBm with OIP3 of 42.5 dBm. A leakage signal cancellation scheme is employed to suppress inevitable Tx leakage into Rx input. At a distance of 90 cm between antenna and tag the average recognition ratio is increased from 0% to 42.8% by the leakage canceller.

We propose a new vehicle tracking system which can detect and monitor vehicles as they break traffic lane rules. Our proposed tracking scheme is based on characteristics of both traffic scene and vehicle. These include: background information, local position, and the size of a moving vehicle. The initial size and position of the vehicle are obtained using a 4-directional contour tracking method. The object contour is made less sensitive to luminosity changes by incorporating a frame differencing operation. Each vehicle can be described with four feature points. The template region is estimated by means of a minimum distance approach with respect to center position. Our experimental results confirm that extraction of feature points from each frame of the scene improves the efficiency of vehicle tracking systems. Furthermore, adjustment of the vehicle region with matched points of template resolves the previous problem of occlusion.

This paper presents a high linear and power-handling single-pole double-throw (SPDT) switch for WLAN 802.11 a/b/g applications. The switch circuit has asymmetric and stacked topology to have high power-handling and linearity for the Tx path. This SPDT switch has been implemented with 0.25 /spl mu/m GaAs pHEMT process by ETRI. The designed SPDT switch has the measured insertion loss of better than 1dB and isolation of better than 40dB for the Tx path and 25dB for the Rx path and the high power handling capability with P/sub 1dB/ of about 23dBm with control voltage of -3/0 V. The fabricated SPDT switch chip size is 1.8 mm /spl times/ 1.8 mm.

Air hoists are widely used in handling of heavy materials in industry. Conventional air hoists necessitate the operation of manual switches for vertical motion, thus the operator has a difficulty in operating of the switches and handling of material at the same time. To overcome such difficulty, this study develops a pneumatic control circuit for weightless material handling with air hoists. The pneumatic circuit memorizes the weight of load in terms of a pneumatic pressure. The pressure is then used as a feedback signal to achieve weightless handling of materials. To demonstrate the effectiveness of the proposed pneumatic circuit, handling forces and the response of the system for various material weights are examined through a series of experiments. The results show that the proposed pneumatic circuit for air hoists can be used in material handling with small manual operation force.

We have developed a 16 channel full add/drop WDM system for long-haul transmission and successfully demonstrated 16 channel 2.5 Gbps transmission over 640 km with single mode fibers and the repeater spacing of 80 km includes optical add/drop multiplexing (OADM). The space between the channels is 100 GHz. We tested the system in a 50/spl deg/C, 80% humidity and in a 0/spl deg/C, 0% environment to measure the wavelength change of the transponder output.