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Cancer cells possess a broad spectrum of invasion mechanisms. Quantitative analysis of cancer cell invasion process under tested condition is important to precisely study the cellular invasion capability. In this study, a microfluidic device was developed and electrodes were embedded in the microchannel for the impedimetric measurement of cell invasion. Cancer cells were stimulated by interleukin-6 cytokine and invaded along the hydrogel-filled microchannel. The three-dimensional (3D) cell invasion process was monitored by measuring the impedance across the electrodes. The cell invasion speed could be calculated based on the cell invasion distance divided by time. Thus, 3D cell invasion process was demonstrated to be quantitatively monitored in real-time and non-invasive manner. The current development provides a promising and quantitative tool for cell invasion assay.

In vitro cell culture device was developed for the investigation of inhibition effect of cell colonies using alternating electric field. Cancer cells were cultured in 3D hydrogel and cell colonies, or called tumor spheroids, were gradually formed in the culture device. During the culture course, alternating electric field was applied and the conditions were investigated to optimize the inhibition effect of cell colonies. Results showed that electric field at frequency of 130 kHz and 0.5 Vpp was the minimal effective conditions of the inhibition of cell colonies. The device was demonstrated to provide a practical tool for the investigation of the efficacy and the therapeutic conditions of inhibiting tumors.

In vitro 3D cell culture device embedded with stimulating electrodes was developed for the investigation of disruption of cell colony formation process. Cells encapsulated in soft hydrogel were cultured and proliferated to cell colonies in the device. Alternating electric field was then applied to investigate the response of cell colonies. Results showed that the electric field at frequency of 130 kHz and potential of 0.5 V p-p was the most effective conditions to inhibit the growth of cancer cell colonies.

Calibration and registration are the first steps for augmented reality and mixed reality applications. In the medical field, the calibration between an RGB-D camera and a mobile C-arm fluoroscope is a new topic which introduces challenges. In this paper, we propose a precise 3D/2D calibration method to achieve a video augmented fluoroscope. With the design of a suitable calibration phantom for RGB-D/C-arm calibration, we calculate the projection matrix from the depth camera coordinates to the X-ray image. Through a comparison experiment by combining different steps leading to the calibration, we evaluate the effect of every step of our calibration process. Results demonstrated that we obtain a calibration RMS error of 0.54±1.40 mm which is promising for surgical applications. We conclude this paper by showcasing two clinical applications. One is a markerless registration application, the other is an RGB-D camera augmented mobile C-arm visualization.

This paper investigates massive spalling that occurs in the intermetallic compounds at the interfaces between Pb-free SAC 305 and Co-based surface finishes. The SAC 305 solders were reflowed on the Co-based substrates and aged at different conditions. The samples were cross-sectioned to study the interfacial morphology. The occurrence of massive spalling depends on the constituents of the substrates. Shear tests were performed on the samples to evaluate the influence of massive spalling on the mechanical strength of the joints. The results indicated that massive spalling did not deteriorate the joint strength.

This paper presents an internationally interoperable marine meteorological information service implemented with the Automatic Identification System (AIS). The service is delivered with both the shore-side system and the shipboard application platform. It is targeted not only to providing services to AIS-fitted vessels but also to collecting weather reports from ships. The intended coverage area includes coastal Taiwan waters and the routes of cross Taiwan Strait vessels. It is now operating, on a trial basis, with several remote broadcast sites and shipboard installations.

Onboard integration of maritime safety information (MSI) with navigation display has been identified as a high priority user need in almost all e-Navigation survey. As a preliminary solution to such user need, a software module is developed in this work. MSI message files received via the onboard receiver are parsed to extract or infer their geospatial extent and time validity from free text, then integrated with the navigation display by correlating with own ship's navigation sensor data and route plan.

In this paper an energy consumption model for enterprise applications is proposed. Based on the model, a commercially available application is chosen as a case study. The results show that the proposed model can correctly reflect the applicationi¦s energy consumption. The study also shows when an organizationi¦s daily operations are highly depending on an application, the energy consumed by the application is not negligible. In fact, the proposed model can provide a new angle for an organization to understand its energy consumption caused by using ICT. In the mean time, with the proposed model a software company can obtain better understanding of how to implement low energy consumption applications which helping reducing organizationi¦s energy consumption.

With the recent 3D display technology improvements, people now can perceive 3D effects in 3D display systems without wearing 3D glasses. However, due to 3D contents are not sufficient enough, the 2D to 3D conversion technique becomes more and more important in the near future. For 2D to 3D video conversion, the most common way is to generate the correspondent depth video from the original 2D video first then synthesizing the desired video by utilizing generated depth videos. The main key point for the 2D to 3D conversion is how to generate the corresponding depth video precisely and efficiently. In this paper, we will propose an efficient depth maps interpolation method from existing pairs of key frames and depth maps. The proposed method contains forward/backward block-based motion estimation/compensation, block refinement, object refinement, and frame selection mechanism. Experimental results show that the proposed method can generate the depth maps successfully and effectively, which will be a great help for 3DTV systems

This paper realizes the humanoid robotic system to service the customers in N tables, and to deliver the ordered meal to the corresponding customer. The proposed system includes the following four subsystems: a humanoid robot with 26 degree-of-freedom, a wheeled vehicle with navigation ability, an N-tables system, and a counter with order collection and task allocation. In the beginning, the orders from the customers in N tables system are transmitted to the counter via the Bluetooth module. After the analysis, the corresponding task is assigned to the humanoid robot. Based on the lines on the ground, the line-follower system under the wheeled vehicle, the designed navigation strategy, and the communication between the humanoid robot and the wheeled vehicle, the humanoid robotic system will walk, turn left or right, drive the vehicle, and reach the neighborhood of the corresponding table. Then the ordered meal is sent to the customer, and then the humanoid robotic and wheeled vehicle return to the counter for the next task. Finally, the experiments valid the usefulness of the proposed system.

In this paper, we present a novel high-gain wide-band dipole antenna for application in a wireless local-area network (WLAN) access point in the 5-GHz band. With proper dimensions chosen for microstrip-line, the proposed antenna can have an enhanced antenna-gain level over a large operating bandwidth covering the 5.2/5.8-GHz bands. This enhanced-gain characteristic is very attractive for practical applications, since it is usually necessary that the antenna gain for frequencies across the 5-GHz band be increased in order to provide a larger operating range for WLAN operations. Details of the proposed antenna design are described, and the experimental results of a constructed prototype suitable for 5-GHz WLAN operation are also demonstrated.

A soft switching interleaved converter with series-connected transformers is presented in this paper. Based on the operation behavior in the proposed converter, each transformer of the series-connected transformers can be operated as an inductor or a transformer. Therefore no output filter inductor is needed in the converter. Asymmetrical pulse-width modulation (APWM) scheme is adopted to control the output voltage at the desired value. Based on the output capacitance of power switches and the resonant inductance including the external inductance and transformer leakage inductance, the resonance can be achieved at the transition interval. Therefore, the zero voltage switching (ZVS) turn-on of power switches can be realized. The voltage stress of switches is limited to equal input voltage. The center-tapped rectifier is used at the transformer secondary side to achieve full-wave rectification. The interleaved PWM operation can reduce the ripple current on the output capacitor. These features make the proposed converter suitable for the dc-dc converter with high output current. The operation principles, steady state analysis and design equations of the proposed converter are provided in detail. Finally, experimental results for a 240 W (12 V/20 A) prototype are provided to verify the feasibility of the proposed converter.

Extracting stable features from face images is very important for automatic recognition of facial expression. In this paper, we apply a face feature extraction approach, namely discriminative common vectors, for the recognition of the six expressions including happy, sad, angry, disgust, fear and surprise. By applying discriminative common vector, we can reduce the dimensionality of image feature and classify them in a lower dimension. Then we use HMM as our classifier to find the time series information of the feature vector projected by common vector. Experimental results on the Cohn-Kanade database demonstrate the validity and efficiency of our approach.

This paper presents a three-phase capacitor clamped converter to achieve power factor correction and harmonic elimination. There are two legs in the proposed converter to achieve three-level pulse-width modulation (PWM) and to control the line currents to be sinusoidal waves. Only eight power switches instead of twelve power switches used in the conventional three-phase flying capacitor converter were used in the proposed converter. Three control loops (DC link voltage control, neutral point voltage control and line current control) are used in the control scheme to achieve DC bus voltage regulation, to balance neutral point voltage and to draw the balanced and sinusoidal line currents. The mathematical model of the converter was derived and the control scheme was provided in the paper. The applications of the adopted circuit topology can be applied to AC motor drive and power quality compensation. Experiments were provided to verify the effectiveness of the proposed control scheme.

A single-phase inverter with capacitor clamped topology is presented to generate a sinusoidal voltage to the critical load. There are two legs in the proposed inverter. One inverter leg is considered of four active switches and one flying capacitor. This inverter leg is operated at high switching frequency to generate three voltage levels on the AC terminal. The other inverter leg is consisted of four active switches without flying capacitor. This inverter leg is operated at low switching frequency to generate two voltage levels on the ac terminal. Therefore, five voltage levels are generated on the ac terminal of the proposed inverter. The control scheme of proposed inverter is easy to implement compared with the conventional capacitor clamped inverter. The control goals of the proposed inverter are generating a sinusoidal output voltage to the critical load and to generate a multilevel PWM voltage waveform on the AC side to reduce the voltage harmonics. The system model and control algorithm are described and analyzed. Experimental results are presented to verify the effectiveness of the proposed control scheme.

A three-phase two-leg neutral point clamped converter with space vector pulsewidth modulation scheme (SVPWM) is presented for power factor correction. The adopted three-level converter has less power switches compared to the conventional three-level three-leg converter. Only eight power switches and four clamping diodes with voltage stress of half DC bus voltage are adopted in the circuit configuration. A space vector pulsewidth modulation scheme is adopted to reduce the switching state of power switches. Based on the adopted control scheme, a proper voltage vector is generated on the AC terminal for drawing the sinusoidal line currents with unity power factor. The simulation results are provided to verify the effectiveness of the proposed control strategy.

A single-phase high power factor rectifier based on capacitor-clamped scheme is proposed to achieve high power factor, low current distortion and low voltage stress of power semiconductors. The carrier-based current controller is used in the inner control loop to track the line current command. A voltage compensator is used to balance capacitor voltages to obtain high quality PWM voltage waveform. A PI-based voltage controller is used in the outer control loop to keep DC-link voltage constant. The proposed control scheme illustrates its validity and effectiveness through the respective simulation and experimental results.

A three-phase four-wire voltage source inverter for power quality compensator under the balanced and unbalanced conditions is proposed to provide balanced three-phase source currents and improve input power factor. The proposed inverter is based on the conventional three-phase voltage source inverter with three additional AC power switches to perform three-level pulse width modulation. The voltage stress of three AC power switches is clamped to half DC-link voltage. The balanced reference line currents are estimated using the DC bus voltage and load currents. A voltage controller is used in the outer loop control to compensate the switching losses of the voltage source inverter. To perform the integrated power quality compensation, hysteresis current control scheme is adopted to track the balanced line current commands in phase with mains voltages. Three voltage levels are generated on the AC terminal of the proposed inverter. Simulation results were provided to verify the effectiveness of the proposed control scheme.

This paper presents a switching mode power supply with zero voltage transition (ZVT) technique to achieve power factor correction based on a commercial available IC. To reduce the switching losses and obtain a high efficiency power supply, a ZVT-based boost converter is used in the front stage to obtain a high power factor. An asymmetrical half-bridge converter is used in the output side to obtain a stable DC voltage. The complete experimental results based on a laboratory prototype were shown in the paper.

A voltage-controlled neutral-point diode-clamped rectifier is proposed to achieve high power factor, low current distortion and constant dc bus voltage. The voltage stress of each power semiconductor of the adopted rectifier is equal to half dc bus voltage instead of full dc link voltage in the conventional switching mode rectifier. A voltage control scheme without current sensor is employed to track the line current command. The control signals of the power switches are derived from the dc link voltage controller and neutral point voltage compensator. A carrier-based PWM scheme is employed to draw a clean sinusoidal line current, high input power factor, regulated dc link voltage and balance capacitor voltages. Three voltage levels are generated on the ac terminal of the adopted rectifier. To verify the proposed operation scheme, performance characteristics are given by the simulation and experimental results.

A control scheme of hybrid active filter with integrated series active filter and parallel passive filter for power quality improvement is presented. The system is capable of compensating the current and voltage harmonics and voltage sag in distribution system. The line current is controlled to be sinusoidal in phase with mains voltage and load terminal voltage is controlled to be fixed under a wide range of distorted line voltage. The power rating of inverter in the series active filter is reduced by comparing with that of pure active filter to suppress the harmonics. A series voltage compensator is used to improve the power quality of load terminal voltage. The control concept of hybrid active filter is analyzed with the experimental results in a scaled-down laboratory prototype to demonstrate the proposed control strategy.