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A high-efficient synchronous rectifier in the receivers, which controls the duty cycle of the rectifier to modulate the load voltage, is proposed in this paper. The proposed rectifier can be utilized to reduce the conduction loss of the switching devices, and to control the load voltage with a simple control circuit. Thus, the load voltage of multiple rectifiers, which are connected in parallel each other, can be regulated for uniformly powering of the receivers under multiple wireless charging condition. In this paper, the new control method of two AC/DC rectifiers installed in the railway vehicle was introduced and verified by simulation. As a result, the uniformly powering of the two rectifier was achieved for 500kW load power delivery by the proposed rectifier with 97.0% of power efficiency, although each receiver has different magnetic field in the railroad track.

This paper presents a new inductorless 5-GHz differential dual regulated cross-cascode transimpedance amplifier (DDRCCTIA) using UMC 40 nm CMOS technology. It consists of a differential cross-coupled input stage (DDRCC) that has a unique dual PMOS and NMOS regulated cascode loops as well as a frequency doubler with active inductor (FDAI) buffer stage. The design has a transimpedance gain of 62.5 dBΩ and bandwidth of 5.02 GHz. The power consumption is 7.34 mW from a 1.8 V supply, input referred noise current of 4.5 pA√Hz and a very small core area of 0.0018 mm2.

This paper presents a new inductorless 6-GHz variable gain differential transimpedance amplifier (VGDTIA) with voltage bias controlled variable gain designed using TowerJazz 0.18-μm SiGe BiCMOS technology (using CMOS only). It consists of a modified cross-coupled regulated cascode preamplifier stage (CCRGC) and a cascaded amplifier stage with bias-controlled gain-variation and third-order interleaving feedback (CVG3F). The design has a transimpedance gain range of 20.6–60.5 dBΩ with constant bandwidth of 6.6 GHz and a dynamic range of 41.2 μΑ to 1.1 mA. The power consumption is 33.9 mW from 1.8 V supply, and the input referred noise current is 10.4 pA/√Hz. This design is compact and the core area is 100 μm × 85 μm.

In December 2015, three hydrophones were moored at the east side of Drygalski Ice Tongue (DIT), seaward of the Nansen Ice Shelf (NIS). On 7 April 2016, the front of the NIS calved into two medium-sized icebergs, presenting a rare opportunity to measure the temporal variation of acoustic signals produced by a large scale ice shelf fracturing event. The acoustic data indicates there are hundreds of short duration, broadband (10–400 Hz) signals throughout the 4-month hydrophone record. We interpret these signals as cryogenic, caused by the cracking of the ice shelves and impacts of nearby sea-ice. The majority of these ice-cracking signals occur during the 21 January to 21 March time frame, two months to two weeks prior to the shelf fracturing observed by satellite on 7 April. Meteorological records of barometric pressure, air temperature, and wind speed show that the day the two icebergs drifted from the NIS coincided with the largest low pressure storm system recorded in the previous 7 months. Our interpretation is the NIS leading edge broke free during the January–March high acoustic energy time period, but the iceberg remained grounded on the seafloor until the low pressure event. The combination of low atmospheric pressure, high winds and high ocean tide, freed the iceberg keel from the seafloor. Strong bio-acoustic signals were also observed on the hydrophones, where the vocalizations of blue whales and leopard seals dominate certain time periods and frequency bands of the long-term acoustic record.

The main focus of this paper is obtaining a fuzzy perception of the environment in the design of each reactive behavior and solving the problem of behavior combination to implement a fuzzy behavior based control architecture. It should be remarked that, the proposed technique of the nonholonomic constraints are considered in the design of each behavior. Furthermore, in order to improve the capabilities of the intelligent control system and its practical applicability, teleoperation and planned behaviors, together with their combination with reactive ones, have been considered.

In this paper, we describe an voice recognition control technology for Mobile robot system which can robustly recognize voice by adults and children in noisy environments. We evaluate the performance of robot control system in a communication robot placed in a real noisy environment. Voice is captured using a wireless microphone. To suppress interference and noise and to attenuate reverberation, we implemented a multi-channel system consisting of an outlier-robust generalized side-lobe canceller technique and a feature-space noise suppression using criteria. Voice activity periods are detected based end-point detection

A high power on-line wireless power transfer system has been investigated intensively in recent years. However, no literature has focused on the design methodology of the high power on-line wireless power transfer system with low flux density, high efficiency, and high control stability. This paper proposed a new design methodology for a 300 kW, over 96%coil-to-coil efficiency, ICNIRP's safety regulation compatible on-line wireless power transfer system. Using a finite element analysis and experimental results, the proposed design methodology has been evaluated.

The influence of logistics on the national economy increases as the economy advances. Vehicle transportation, however, cannot meet the ever-increasing transportation demand, with its economic efficiency deteriorating over time. Judging that such transportation demand cannot be met only by vehicle transportation, the government also seeks to increase transportation through railroads. In this study, the voltage supplied to train in trial operation was monitored and analyzed to identify the voltage condition supplied by the existing railroad. To directly measure the voltage supplied to train, PT was installed at the bottom of train pantograph for monitoring the primary voltage of the transformer, and for accurate measuring, surrounding environment and conditions were recorded and the analysis of stringing voltage using CBEMA curve was conducted. As a result, some of the section on Honam, Jonngang and Taebaek line were supplied 110[%] pf rated voltage (25[kV]) for more than 200[s] frequently exceeding 110[%] Taebaek line appeared to have had the installed voltage in worst condition.

Urine test strips are frequently used to analyze health status of patients due to its simplicity. However, in order to analyze the urine test strip, expensive hardware is required to match changed colors. In order to solve the problem, a novel design of the urine test strip is proposed. By using the proposed design, extra equipment is not required and the proposed design is robust against illumination changes. Through a series of experiments, the proposed design gives a correct decision in general, dim, and flash light condition.

Generally, it is possible to control the motion by using information on the robot's own postures, because a type of motion and gesture produces almost the same pattern of every time. In this paper, we describe a voice recognition control system for robot system which can robustly recognize voice by adults and children in noisy environments. We evaluate the performance of robot control system in a communication robot placed in a real noisy environment. Voice is captured using a wireless microphone. To suppress interference and noise and to attenuate reverberation, we implemented a multi-channel system consisting of an outlier-robust generalized side-lobe canceller technique and a feature-space noise suppression using criteria. Voice activity periods are detected based end-point detection.

We present a new technology for real-time walking of a biped robot. A biped robot necessitates achieving stabilization for real time walking since it has basic problems such as structural stability. In this paper, a robust control algorithm for stable walking is proposed based the ground reaction forces, which are measured using force sensors during walking, and the environmental conditions are estimated from these situation. From this information the robot selects the proper motion and overcomes ground irregularities effectively. In order to generate the proper angel of the joint. The performance of the proposed algorithm is verified by simulation and experiments for a 20-DOFs humanoid robot.

Recently, an interest in a hybrid system combining only the merits of the conventional wheel-rail system and Maglev propulsion system is growing as an alternative to high-speed maglev train. This hybrid-type system is based on wheel-rail method, but it enables to overcome the speed limitation by adhesion because it is operated by a non-contact method using a linear motor as a propulsion system and reduce the overall construction costs by its compatibility with the conventional railway systems. Therefore, designs of each coreless-typed LSM with a distributed winding and a concentrated winding for 600 km/h very high speed train maintaining the conventional wheel-rail method is conducted, and a comparative analysis on electromagnetic characteristics of each model is finally conducted in this paper.

Generally, it is possible to control the motion by using information on the robot's own postures, because a type of motion and gesture produces almost the same pattern of noise every time. In this paper, we describe an voice recognition control system for robot system which can robustly recognize voice by adults and children in noisy environments. We evaluate the performance of robot control system in a communication robot placed in a real noisy environment. Voice is captured using a wireless microphone. To suppress interference and noise and to attenuate reverberation, we implemented a multi-channel system consisting of an outlier-robust generalized side-lobe canceller technique and a feature-space noise suppression using criteria. Voice activity periods are detected based end-point detection.

We present a new technology for real-time walking of a biped robot. A biped robot necessitates achieving stabilization for real time walking since it has basic problems such as structural stability. In this paper, a robust control algorithm for stable walking is proposed based the ground reaction forces, which are measured using force sensors during walking, and the environmental conditions are estimated from these situation. From this information the robot selects the proper motion and overcomes ground irregularities effectively. In order to generate the proper angel of the joint. The performance of the proposed algorithm is verified by simulation and experiments for a 20-DOFs humanoid robot.

The influence of logistics on the national economy increases as the economy advances. Vehicle transportation, however, cannot meet the ever-increasing transportation demand, with its economic efficiency deteriorating over time. Judging that such transportation demand cannot be met only by vehicle transportation, the government also seeks to increase transportation through railroads. In this study, the voltage supplied to TTX in trial operation was monitored and analyzed to identify the voltage condition supplied by the existing railroad. To directly measure the voltage supplied to TTX, PT was installed at the bottom of TTX pantograph for monitoring the primary voltage of the transformer, and for accurate measuring, surrounding environment and conditions were recorded and the analysis of stringing voltage using CBEMA curve was conducted. As a result, some of the section on Honam, Jonngang and Taebaek line were supplied 110[%] pf rated voltage (25[kV]) for more than 200[s] frequently exceeding 110[%] Taebaek line appeared to have had the installed voltage in worst condition.

Korean-style EMU(Electric Multiple Unit) train which was developed by Korea Railroad Research Institute (KRRI) has been in trial operation on Honam, Jonngang, Choongbuk and Taebaek line. In this study, the voltage supplied to EMU Train in trial operation was monitored and analyzed to identify the voltage condition supplied by the existing railroad. To directly measure the voltage supplied to EMU Train, PT was installed at the bottom of ttain pantograph for monitoring the primary voltage of the transformer, and for accurate measuring, surrounding environment and conditions were recorded and the analysis of stringing voltage using CBEMA curve was conducted. As a result, some of the section on Honam, Jonngang and Taebaek line were supplied 110[%] pf rated voltage (25 [kV]) for more than 200[s] frequently exceeding 110[%] Taebaek line appeared to have had the installed voltage in worst condition. The analyzed data is expected to be helpful in stabilizing the power system and power conversion system of train which will run Jonngang and Taebaek line.

Two types of antenna topology are proposed to identify a high speed RFID tag. To identify the high speed tag, the time that the tag stays in the reading range of the RFID reader should be longer than backscattering time. Therefore the near-field beam width of the reader antenna was widened along the moving direction of the tag. The first antenna type is an array antenna and the second one is a traveling wave antenna. Measurement results show that both antennas have more wide identification range compared with a single antenna.

Precision coaxial airline electrical characteristics can be derived from their physical properties such as physical dimensions and material properties. Characterizing a precision airline requires accurate physical measurements of the airline's internal diameter, lengths of outer and center conductors, pin depth, surface finish and material properties. Characteristic impedance, which is calculated from dimensional measurements, is an extremely important end result. Traceable, physical dimensional measurements of 0.800 mm coaxial outer conductor bore diameters and outer diameters of center conductors are presented. The development of these traceable 0.800 mm coaxial airline impedance standards arose from the need to support Vector Network Analyzer coaxial measurements from 70 kHz to 145 GHz[1].

This paper has been designed the miniaturized LPDA antenna applying the triangular meander structure. To reduce the basic LPDA antenna, four dipole elements for low frequency band of the basic LPDA antenna were changed into triangular meander structure except for the other elements to keep the performance of high frequency band. The proposed antenna was miniaturized up to 60 % compared with the basic LPDA antenna. The average gain was measured as 6.69 dBi.

It is desirable and advantageous to feed parallel propulsion with induction motors by a single voltage source inverter. However, effects of deviation of the wheel diameters on motor current, rotor speed and torque should be also considered for parallel operation. In order to understand the behavior and characteristics, a simple simulation model is developed by using a commercial Matlab Simulink. From the results, it is clear to manage the diameter deviation of the wheels which are connected to traction motors.

As a new concept of energy transmission systems out of the existing catenary and pantograph method, Inductive Power Transmission System (IPTS) has been studied on a variety of applications in the field of railway systems recently, but there are still a lot of technical issues to solve in order to apply the IPTS system to a large system such as high-speed railway system. For railway applications, the IPTS will transfer energy while train stops at a station for around 30 seconds. The airgap of IPTS for railway system is larger than one of the home appliance and the coupling coefficient will decrease due to the large airgap ; consequently capability of the power transfer will decrease compared with the direct current collector. Therefore, equivalent circuit parameters and coupling coefficient of Inductive Power Transmission Module(IPTM) are an important design factor for the high energy transfer efficiency. This paper investigates the properties of equivalent circuit parameters and coupling coefficient of U-U type IPTM and U-I type IPTM using an analytical method and experimental method. In addition, it is important to predict the tempertatire property of the IPTM during power delivery operation because the primary part of the IPTM should be buried in the ground track. Therefore, The thermal analysis is performed using FEM for the prediction of temperature property during operation of the IPTM in this study.

This study explored the effects of characteristics of TV program subtitle, including character font, character size, and position of the subtitle on preferred viewing distance and subjective preference for liquid crystal display high-definition television (LCD-HDTV). The results showed the mean preferred viewing distance was 3516 mm, about 4.3 times of television width. Character font had significant effect on PVD; PVD was longer for New Xi-Ming style than Biao Kai style. Character size had significant effect on PVD: the larger the character size, the longer the PVD. Character font had no significant effect on subjective preference. The effect of character size on subjective preference was significant. Subjective preference increased as character size increased from 10 pt, 20 pt to 30 pt, then it decreased when character size was 40 pt. Subtitle position had no significant effect on PVD and subjective preference.

Genetic Algorithm (GA), one of the artificial intelligence algorithms, performs much better than the other algorithms for the document clustering. However, it has problem known as the premature convergence occurrence. So, Fuzzy Logic based GA (FLGA) was proposed to solve it. Nevertheless, it has still weakness such as the parameter dependence problem. In order to overcome this problem, the Multi-Objective Genetic Algorithms (MOGAs), NSGA-II and SPEA2, have been proposed. The MOGAs showed high performance compared to other algorithms including the general GA, but their computational times have increased. In order to reduce these computational times, the distributed computing method, MATLAB Distributed Computing (MDC) with 10 processors, is applied to the MOGAs in this paper. The performances of MOGAs on MDC show about 12% higher than others.

This study explored the effect of screen luminance, subtitle, and viewing angle on preferred viewing distance for liquid crystal display high-definition television (LCD-HDTV). The results showed the mean preferred viewing distance was 3246 mm, about 4 times of television width. Preferred viewing distance increased as the scale of screen luminance went upward from scale 10 to scale 60, then decreased from scale 60 to scale 90. Whether there was subtitle or not did not have significant effect on viewing distance. Moreover, viewing angle was highly correlated with preferred viewing distance. The more deflected from the direct front view, the shorter the viewing distance was.

This study investigated the effects of chromaticity and luminance on legibility and subjective preference for imagery presented on LCD. The results showed that chromaticity and luminance had little effect on legibility speed. Both chromaticity and luminance significantly affected subjective preference. Chromaticity seemed to be more important than luminance for subjective preference. Participants appeared to prefer medium luminance, they also showed less preference for achromatic imagery. Regression equations for legibility speed and subjective preference were constructed. Correlation analysis showed that the equations were better than Lippert's ?GE (CIE Y, u', v').

A fine directional deinterlacing using virtual edge distribution (FDVED) is presented. The proposed method can preserve delicate edges having various forms. From the subjective and objective perspective, experimental results demonstrate that FDVED outperforms the conventional deinterlacing methods.

Three-dimensional (3D) shape models have recently been used in various fields including machine designing, internet mall, and medical application. Therefore, efficient management and reuse of 3D shape models is becoming important with research on object searching of 3D shape models. 3D shape model searching requires taking into consideration rotation, scaling, and translation of models. This paper proposes a method to search 3D objects to include and account for the above conditions. The proposed method acquires 2D range images by rendering a 3D object from many viewpoints, and discretely approximating two of the three degrees of rotational freedom by a finite number of viewpoints. Using the phase correlation method on the range image one can estimate the rotation around one axis, include scaling and translation, and compare the similarities between the input with models in a dictionary. Experimental results show that whether models match or not match can be distinguished even when the supposed viewpoints are limited to a finite number.

In this study, a 1.5 [kW] on-board battery charger for neighborhood electric vehicles was developed. The developed charger has a built-in power factor correction circuit and a resonant phase shift full-bridge (PSFB) for power conversion. Although an additional snubber is not used, the switching noise generated in the switch and the diode is reduced, owing to the built-in resonant-type PSFB converter, and the desired improvement in noise reduction and efficiency of input/output is achieved. The power conversion controller was controlled using a dedicated integrated circuit.

In this paper, we present an adaptive sharpening filter for a pre-processing to improve the subjective quality and the performance of H.264/AVC compression. We use quantization step size and pixel variance to select sharpening filter strength. The simulation results show that the proposed pre-processing filtering process improves the subjective quality and reduces bit rate about 0.85%(CIF) and 1.46%(1080p).

In this paper, we present two kinds of robust control schemes for robot system which has the parametric uncertainties. In order to compensate these uncertainties, we use the neural network control system that has the capability to approximate any nonlinear function over the compact input space. In the proposed control schemes, we need not derive the linear formulation of robot dynamic equation and tune the parameters. We also suggest the robust adaptive control laws in all proposed schemes for decreasing the effect of approximation error. To reduce the number of neural of network, we consider the properties of robot dynamics and the decomposition of the uncertainty function. The proposed controllers are robust not only to the structured uncertainty such as payload parameter, but also to the unstructured one such as friction model and disturbance. The reliability of the control scheme is shown by computer simulations and experiment of robot manipulator with 8 axis.

In general, it is possible to estimate the noise by using information on the robot's own motions and postures, because a type of motion and gesture produces almost the same pattern of noise every time. In this paper, we describe an voice recognition control system for robot(VRCS) system which can robustly recognize voice by adults and children in noisy environments. We evaluate the VRCS system in a communication robot placed in a real noisy environment. Voice is captured using a wireless microphone. To suppress interference and noise and to attenuate reverberation, we implemented a multi-channel system consisting of an outlier-robust generalized side-lobe canceller technique and a feature-space noise suppression using MMSE criteria. Voice activity periods are detected using GMM-based end-point detection.

This paper is to devise the application model of wireless sensor networks in order to increase effectiveness of management system in exhibition. The networks combine ubiquitous sensor networks technology and the digital archives of the exhibits. Its purposes are to implement the automatic and accurate control of physical conditions of the objects such as location, temperature, and humidity changes in exhibition rooms. In addition, exhibition managers/curators can enhance easy access to the database through the web interface at real-time. It helps to change the management based on the man’s labor work to the computerized active system using ubiquitous sensor networks.

In this paper presented pressure drop characteristics in one channel of plate heat exchanger by experimental method. Plate Heat Exchanger (PHE) applied in vacuum evaporator for product fresh water. PHE have become popular in chemical, power, food and refrigeration industries due to the efficient heat transfer performance, extremely compact design and flexibility of extend or modify to suit changed duty. The heat transfer part contains corrugated plates with 60 degree of chevron angle. The experiments carried out pressure profile according to mass flow rate at 15 measure points for investigate flow characteristics of PHE channel flow which highly turbulent even with low Reynolds number. In addition, numerical simulation was compared with experimental results and present more visible distribution of flow behavior in the test section.

This paper presents the influence of flatness of the secondary reaction plate on performance of a linear induction motor. Construction tolerance of the plate affects directly to the cost and performance of the Linear metro. Detailed simulation of the flatness has been done by using FEM.

Metrological traceability is defined as the property of a measurement result whereby the result can be related to a reference through a documented unbroken chain of calibrations, each contributing to the measurement uncertainty.

An inline power sensor is used to measure the forward power passing from an RF source to load. It can be used to measure power under operating conditions such as during the installation, maintenance, and monitoring of base station transmitters. This paper is to report an overview of the characterization of key components of Anritsu Company's MA24104A Inline High Power Sensor. The characterization method is based on recommended international standards. A brief description of the architecture and operational principle of the sensor will be presented. Finally, uncertainty budgets based on the measurement model for the inline power measurement are calculated.

This paper proposes a new video coding algorithm using the multi-dimensional transform. The multi-dimensional transform achieves both the accuracy of temporal prediction as well as effective use of spatial redundancy. Moreover, two additional methods for multi-dimensional transform are proposed, which are cube forming and modified transform coefficient thresholding. These combined schemes lead to a bitrate saving on FRExt profile, compared to an H.264/AVC standard codec, which reach up to 2.88%.

This paper describes recent research that aims to improve upon our use of case-based reasoning in Texas hold'em poker bot called CASPER. CASPER uses knowledge of previous poker scenarios to inform its betting decisions. CASPER improves upon previous case-based reasoning approaches to poker and is able to play evenly against the University of Alberta's Pokibots and Simbots, from which it initially acquired its case-bases and updates previously published research by showing that CASPER plays profitably against human online competitors for play money. The new research described here shows how CASPER has improved its play against human players by remembering and reusing its own game play history.

This paper presents two kinds of adaptive control schemes for robot manipulator which has the parametric uncertainties. In order to compensate these uncertainties, we use the NN (neural network system) that has the capability to approximate any nonlinear function over the compact input space. In the proposed control schemes, we need not derive the linear formulation of robot dynamic equation and tune the parameters. We also suggest the robust adaptive control laws in all proposed schemes for decreasing the effect of approximation error. To reduce the number of neural of network, we consider the properties of robot dynamics and the decomposition of the uncertainty function. The proposed controllers are robust not only to the structured uncertainty such as payload parameter, but also to the unstructured one such as friction model and disturbance. The validity of the control scheme is shown by computer simulations and experiment of dual-arm robot manipulator.

In order to realize a traction system with high efficiency and performance for a railway transit, many researchers have continued to study on a linear induction motor (LIM). However, most of researches are limited in LIM unit design. On a moving LIM, the change of an air-gap (it occurs by a construction tolerance of a secondary reaction plate) can lead to decrease a smoother ride and efficiency of the railway transit system. Therefore, a uniform air-gap operation of the LIM is important issue to improve the system efficiency. However, the researches about the air-gap length control of the LIM have been not advanced a lot due to a technical and high-cost problem. Therefore, in this research, the authors introduce an air-gap control system to control the air-gap length which depends on the flatness of the secondary reaction plate when the LIM is been operating. Then, through a dynamic modeling and analysis of the system, the authors analyze characteristic variations of some parameters (spring coefficient, damping coefficient, displacement, and exiting force) which compose the system, and conduct a research on feasibility of the system.

Typical power measurement references to the point value of 1 mW at 50 MHz. This point provides a traceability path to the National Standard for microwave power measurement. The Anritsu MA2411B pulse sensor starts with a low end of 300 MHz. Therefore, the reference power is set at 1 GHz. This report discusses the details of the test procedures and uncertainty budget in establishing specifications of reference output power uncertainty for the combination of power meter ML2488A and power sensor MA2411B. We will review different sensor and meter options when making a direct power measurement. A detailed uncertainty budget will be presented when making direct power measurement using the MA2411B. All uncertainty budgets are based on the guideline of the ISO Guide to the Expression of Uncertainty in Measurement (GUM) [1].

The status of calibration service for vector network analyzers (VNAs) is introduced. Some recommendations are proposed to provide an efficient and traceable calibration service for VNA.

Historically the performance of Anritsu precision airlines was characterized using the swept reflectometer. The worst error or uncertainty of the airline was determined based on the ripple techniques. This usually includes the effect of the connectors or defects at the interface of the connections. As the ISO Guide to the expression of uncertainty in measurement (GUM) and ISO 17025 have become popular in recent years, customers are demanding more accurate uncertainty statements for the precision airlines. Therefore, we have investigated the time-domain gating methods of vector network analyzers (VNA) to determine the performance of the precision airlines and sources of their defects. In this paper, the author will discuss the time-domain gating method setup. The experimental results will also be presented.

In order to build an animal PET system with high sensitivity and resolution, we propose a four-layer PET system which provides the DOI (depth of interaction) information. Each crystal layer has a relative offset of half the crystal pitch with each other and uses an identical type of crystals simplifying readout electronics. The proposed system PET system consists of four LYSO (Lu18Y0.2SiO5:Ce) or L0.9GSO (Lu1.8Gd0.2 Si0.4:Ce) crystal layers with a crystal dimension of 1.5times1.5times5.0 mm3. The animal PET system has a diameter of 84 mm with one Hamamatsu H9500 flat panel PMT ring, and can be upgraded to two PMT ring configuration. An estimated efficiency using GATE simulation is ~15% at the center of one detector ring system. We present flood images obtained with a 22Na radiation source to verify the concepts of the proposed system, and obtained promising results.