Search

With a lot of researches focusing on hyperthermia treatment technology, thermoseed mediated magnetic induction hyperthermia (MIH) has the potential to become a clinical intervention for tumor. While, quantitative thermoseed distribution in tumor is a key technical problem for thermoseed mediated MIH treatment plans. In order to solve this problem, a reverse optimization algorithm (ROA) is proposed to use a minimum number of thermoseeds to achieve the desired temperature distribution which meets the treatment needs. An improved simulated annealing algorithm is applied to generate conformal thermoseed distribution with that the tumor achieves irreversible thermal damage and the temperature distribution in normal tissues is controlled in a safe range. Because of the specialty of the thermoseed distribution problem, initial temperature, stop condition, evaluation function, annealing strategy, and specific calculation steps are redefined. Finally, computer simulation was used to model the tumor region and generate the thermoseed implant model as well as the temperature distribution. According to the application in MIH planning system, the feasibility of ROA to solve the problem of thermoseed distribution was verified. This research can promote the application of the magnetic induction hyperthermia computation method to clinical trials, which will improve the safety, efficacy, and accuracy of clinical trials in the future.

Because that magnetic inductive thermotherapy requires to implant magnetic inductive media in tumor area with heating under the stimulation of external alternating magnetic field and is a clinical interventional treatment, so it is very important and essential for a doctor to make a reasonable treatment plan in magnetic inductive clinical treatment diagnosis and preoperative plan. The intuitional three-dimensional virtual patient information plays a vital function in making a plan. The research takes advantage of computer graphics algorithm to study the drawing of three-dimensional visual surface of medical image, extracts and launches a study on contour surface through voxel model, contour surface model and MC (Marching Cubes) algorithm and achieves the visual process of three-dimensional surface drawing of medical CT (Computed Tomography) sequence images, which can clearly build well-defined and intuitive virtual focus model and improve the quality and accuracy of thermotherapy plan.

As we know, with the increase of input signal bandwidth, the asymmetry of upper and lower sideband of the third-order intermodulation distortion (IMD) will become more evident. The industry describes this asymmetric phenomenon as the memory effect of the microwave component. For simplicity, the third-order intermodulation distortion (IM3), the major part of IMD, is chosen in investigating the conditions for IMD asymmetry. With the rapid communication systems, the bandwidth of the input signal becomes wider and wider, and the memory effect becomes very significant. Therefore, it's necessary to study the asymmetry of IM3. Today, taking the advantages of three signal generators and a spectrum analyzer, the first investigation into the effect of different excitation conditions to the memory effect of double balanced diode mixer. The different excitation conditions include frequency separation, the power of the radio-frequency (RF) signal and the local oscillator (LO) signal, and so on. For the first time, the measurement results show the impact of the input signal (LO signal and RF signal) power and the relative size of LO frequency and RF frequency on mixer memory effect.

For small size devices, fan-out chip-embedded technology has become an attractive and holistic packaging solutions with various advantages in comparison to conventional and mature technology. And high efficient and high reliability of the embedded package for small-size power devices has become a hot topic in industry. In this paper, a novel panel level double side-embedded packaged process (DS-Embedded) for small size power devices has been presented. The entire process can be performed on both sides of the carrier. In order to reduce cost and time-to-market, 2D and 3D finite element model were used to get a reliable package structure. The result shows that the thermomechanical fatigue life of the model after parameter optimization is much larger than the actual use requirements which was in good agreement with the experimental result. The actual reliability tests such as vibration, mechanical shock, shear test also prove the feasibility of the product. However, the failure problem caused by Ag corrosion and migration in the H3TRB experiment still needs further improvement.

With the rapid development of the society, space utilization is constantly increasing, and the building height is also increasing rapidly, the problems of wall surface cleaning, damage detection and equipment maintenance are coming up. Using robots to replace human tasks can not only reduce the risk and cost but also improve the efficiency of the operation. Glass wall cleaning robot with negative pressure type double suction cup can move smoothly by sliding friction between suckers and glasses, therefore, by studying a reliable control algorithm, the robot can be controlled to move smoothly on the glass wall, at the same time, the glasses can be cleaned by the cleaning devices. In order to solve the obstacle avoidance and balance problem, a glass wall cleaning robot controlled by ATMEGA128A is proposed. Through designing the core algorithms such as mobile module algorithm, adsorption system algorithm etc., the robot can complete the scheduled cleaning tasks. The experiments of the designed glass wall cleaning robot prototype show that this glass wall cleaning robot designed here can clean wall, which can meet the realization requirements, and the given control algorithms are fast and stable.

A Single-Photon Avalanche Diode (SPAD) design solution that can be implemented in a low cost CMOS process, n-well 0.5μm process, is proposed. This SPAD design used the lateral diffusion of the n-wells to create a low n doping density area as the guard ring to prevent the premature breakdown at the edge of SPAD. Through the TCAD simulation and fabricated design characterization, we found the proper gap length between n-wells to create the guard ring that allows the SPAD to work in the Geiger Mode. The SPAD has dark count rate (DCR) of 750/Hz at 14.85V bias voltage without cooling and 60ns dead time.

Time-Correlated Single Photon Counting (TCSPC) can provide not only the time information of a photon, but also the photon density information. Based on the conclusion of usual time interval measuring methods, this paper chooses the scheme of Time-to-Digital Converter (TDC) based on delay line structure, meeting the TCSPC system's requirement for high timing resolution. This TDC contains two delay lines and a main counter. After finishing the framework of the TDC using Verilog, we confirm the architecture of the delay element by simulation and on-board test. Using the histogram from FPGA, the TDC system implement is for time resolution below 200 ps.

Quiescent current is a key technical parameter for automotive electronic devices. Currently there are few researches on testing method for quiescent current from domestic automobile manufacturers. With actual demand from domestic automobile manufacturers, a testing method for quiescent current of automotive electronic devices is proposed in this paper. Current data of each electronic device are acquired by voltage measurement with a measurement instrument. The testing system is established with the measurement instrument and the testing software, which is developed to cooperate with the instrument. The software can be used to acquire, decode, display and analyze the test data automatically in real time, and generate evaluation report. The testing system fulfills the requirement of quiescent current test and is proven effective in field test.

We proposed a portable molecular diagnostic tool implemented by CMOS and Microfluidic technology for the early HIV diagnosis. Our system diagnoses HIV by detecting the P24 antigen concentration in blood sample. We labeled P24 antigens with chemiluminescence signal, which can be detected by our CMOS photon detector. We designed the single photon avalanche diode (SPAD) with single molecule sensitivity, which can help to diagnosis HIV patient earlier, thus increases the chance of cure and reduce the change of further infection spread. To make the system reusable, we use the 10 um diameter magnetic beads as the assay substrate, which can be coated with the anti-P24 antibodies. These magnetic beads can be delivered through microfluidic channels to the sensing area. Then they can catch p24 antigens from the blood sample and generate chemiluminescence signal. After the test, the magnetic beads can be easily washed away, and the system can be reused.

Recently, Single Photon Avalanche Diode (SPAD) draws attentions because of its applications in bio-molecule detection [1] and optical communication [2]. In order to reduce the cost and improve the detection throughput, one trend is to integrate large number of SPAD pixels with readout circuit and signal processing circuit on one silicon chip. In this paper, a SPAD is designed and simulated based on the standard CMOS 0.5¼m technology. This design uses lateral diffusion of n-wells to form a low doping n-guard ring to suppress perimeter breakdown at the pn junction edge. To prove our design can prevent perimeter breakdown, we used the semiconductor device simulation to show where the breakdown happened on junction. Our proposed SPAD design doesn't need advanced CMOS process, therefore allows designer to integrate large number of SPAD pixels with relative lower cost.

A novel circular shape CMOS Hall Effect sensor design is proposed in this paper. Compared with traditional rectangular shape Hall Effect sensor, the proposed design can improve the sensitivity significantly. By implementing this sensor design with readout circuit, amplifier and DSP circuit in a CMOS chip, the Enzyme-Linked Immunosorbent Assay (ELISA) can be replaced by a lower cost, more portable and higher sensitive magnetic bead labeled immunoassay platform, which could eventually realize molecular diagnosis on chip.

SAW filters are often used in wireless communications and provide significant advantages in performance, cost, and size over other filter technologies [1]. As a passive device, how to minimize loss is a very important issue for SAW filter design. This paper proposes a new MEMS SAW filter design to minimize insertion loss in the SAW device. By finite element modeling and simulation, this new design has approved to decrease the insertion loss by more than 10 dB, and increase the Q factor by more than 30%. The major novelties of the structure include new IDT finger structure, piezoelectric material edge etching, and metal shell reflectors.

Flaw contour recognition is very important to heavy Plate Ultrasonic Testing (PUT) which is used to classify the plates used for ships, pressure vessels and nuclear power plants. The state-of-the-art contour recognition algorithm is too slow or inexact to be used in field. A Fast Flaw Contour Recognition (FFCR) algorithm is developed which is a hybrid of Convex Hull (CH) and Edge Detection (ED). This paper focuses on how to combine CH and ED to describe planar concave flaw contour and to recongize the flaw local outline quickly and exactly.

We demonstrate single-chip analog sensor-conditioning with integrated electrically-adjustable passive resistors, allowing adjustment by the sensor-system assembler, without the drawbacks of digital conditioning. Adding a rudimentary bulk-silicon cavity-etch to a standard 1mum CMOS process enables a group of innovations for thermally-isolated adjustable resistors, called RejustorsTM.

This report is a part of ongoing research to develop high temperature optical sensors. We report our design and analyze of a hydrogen loaded fiber Bragg grating (FBG) temperature sensor range from room temperature to over 1000/spl deg/C. FBGs were fabricated in hydrogen loaded Ge-doped fibers using 248 nm excimer laser and their performance characteristics were tested. The gratings have shown stabilized at temperatures in excess of 700/spl deg/C and survived at temperatures in excess of 930/spl deg/C. These testing reveal the thermal reliability of tested gratings is related to the refractive index modulation inside the core of FBGs. In this research, we also found the high temperature resistance FBG could be formatted using conventional hydrogen loaded FBG, and stabilized in excess of 1000/spl deg/C. Our experimental results provide a better understanding of the formation to the hydrogen loaded FBGs and their decay behavior at elevated temperatures.

Fiber Bragg grating (FBG) temperature sensor and sensor arrays were applied widespread particularly in harsh environments. Although FBGs are often referring to permanent refractive index modulation in the fiber core, exposure to high temperature environments usually results the bleach of the refractive index modulation. The maximum temperature reported for the conventional FBG temperature sensor is around 600 degC due to its weak bonds of germanium and oxygen. In this paper we report design and development of a novel high temperature resistance FBG temperature sensor, based on the hydrogen loaded germanium doped FBG. The refractive index modulation in the FBG is induced by the molecular water. The results of our experiments have shown that the stability of the device at high temperatures is substantially increased. Due to the high bonds energy of hydroxyl and the low diffusivity of the molecular water, the thermal testing results of this temperature sensor show the thermal stability of hydrogen loaded FBG can be increased using annealing treatment; moreover, the highest erasing temperature for the device is above 1000 degC. Furthermore, the experimental results has provided a better understanding of the formation of the hydrogen loaded FBGs and the chemical transfers at elevated temperatures in the fiber core