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Oesophageal cancer (OC) is associated with high morbidity and mortality, and surgery is the most effective approach to treat it. In order to reduce surgical risks and duration of surgery, we explored a new strategy to determine tumour margins in surgery. In this study, we included 128 cancerous and 128 noncancerous database entries obtained from 32 human patients. Using internal extractive electrospray ionization-MS, in positive ion detection mode, the relative abundances of m/z 104.13, m/z 116.10, m/z 132.13, and m/z 175.13 were higher in cancer tissue while the relative abundances of m/z 82.99, m/z 133.11, m/z 147.08, m/z 154.06, and m/z 188.05 were higher in normal tissue. Using partial least squares analysis, the mass spectra of cancer samples was discriminated from those of normal tissues, and the discriminatory ions were obtained from loading plots. Dimethylglycine(m/z 104), proline(m/z 116), isoleucine(m/z 132), asparagine(m/z 133), glutamine(m/z 147), and arginine(m/z 175) were identified by collision-induced dissociation experiments. Using the ROC curve analysis, we verified the validity of six amino acids for the identification of tumour tissue. Further investigations of tissue amino acids may allow us to better understand the underlying mechanisms involved in OC and develop novel means to identify tumour tissue during operation.

In this paper a measurement method for InP-Based HBT devices to 220GHz is presented. S-parameters are deembedded using TRL calibration structures (70-220GHz) fabricated on-wafer. The results shown in this paper are characterized at 75-110GHz and 140-220GHz. Good agreement between the low and high frequency measurement is achieved demonstrating the capability of TRL calibration in S-parameters extraction. Small signal equivalent circuit for InP DHBT up to 220G Hz is also demonstrated. Excellent agreements between measured and simulated data are obtained in the frequency range of 0.2 to 220 GHz. A six-stage amplifier MMIC designed based on the HBT model is also presented. Measurement results show that the small signal gain of the amplifier is greater than 15 dB over 140–190 GHz.

Mobile Labs (M-Labs) are a mobile enabled version of E-Labs, which is a new way to deliver engineering laboratories based on the advanced Information and Communication Technology (ICT) and rapid development of portable devices. With the M-Remote-Labs, which use the real world physical laboratories and remote control technology along with interfaces in mobile devices, students can conduct experiments using mobile devices at anytime from anywhere in a similar way that they conduct these experiments in physical laboratories. This can bring in great convenience to students and further enhance students' engagement. This paper presents a conceptual design of M-remote-Labs based on a university campus Wi-Fi network. This M-Remote-Lab includes three major parts, (i) the back-end physical experimental systems along with the remote control facilities, (ii) a sub-system for students to conduct engineering experiments remotely using mobile devices based on a hybrid structure, which combines the Browser/Server (B/S) structure and the Client/Server (C/S) structure for students to conduct experiments; (iii) a sub-system for teaching staff to manage the experiments based on a B/S structure. The control of devices and equipment will be realized by a mobile interface. The experimental results will be captured by cameras and transferred to the server and then sent to the mobile interface upon request as video files. An example of using this M-Remote-lab for the course of Bachelor of Engineering Major in Automation in the Beijing Institute of Technology China is described. It can be seen from this example that this M-Remote-Lab can provide great convenience for students to conduct real physical experiments remotely using mobile devices, just like they do the experiments in a real physical laboratory.

An InGaAs/InP DHBT with InGaAsP composite collector is designed and fabricated using triple mesa structure and planarization technology. All processes are on 3-inch wafers. The DHBT with emitter area of 0.5×5μm2 exhibits a current cutoff frequency f t =350GHz and a maximum oscillation frequency f max =532GHz which is to our knowledge the highest BV CEO ever reported for InGaAs/InP DHBTs in China. The breakdown voltage is 4.8V. The high speed InGaAs/InP DHBTs with high breakdown voltage are promising for voltage controlled oscillator (VCO) and mixer applications at THz span.

A common base four-finger InGaAs/InP DHBT with 535 GHz fmax using 0.5μm emitter technology is fabricated. Multi-finger design was used to increase input current. Common base configuration was compared with common emitter configuration, and demonstrated a smaller K factor at high frequency span, indicating a larger MSG/MAG breakpoint frequency and thus a higher gain when frequency reaches MAG region of common emitter devices.

This paper introduced a thru-reflect-line (TRL) calibration standard design for on-wafer measurement. The calibration kits were simulated and fabricated on Indium Phosphide (InP) substrate. The calibration kits covered a range of frequencies from 70 to 220 GHz. On-wafer calibration performed with the microstrip transmission line style contacts was described in this work . The calibration is sufficient to extract reliable device data from measurements. This paper also decribed a thru de-embedding method . This method show reasonable performance up to 60 GHz. Thru de-embedding method and TRL calibration are compared with the simulated transmission lines up to 220 GHz. The measurement result with TRL calibration method shows good agreement with the simulation result.

In order to improve the resolution and conversion speed of photoelectric transducer, a high sensitive and low dark current CCD image sensor TCD1711DG was used in SQ-70D digital quartz horizontal pendulum tiltmeter. The timing chart of CCD has fixed state transition and rigorous timing requirements at typical pulse frequency. Then, a method of controlling the pulse state transition was developed by synchronous counting. The driver was carried out by using Verilog HDL based on CPLD. Simulation and experimental results indicated that the driver designed by this method was simple and stable enough to meet the timing requirements of TCD1711DG. Furthermore, integration time of the CCD could be revised flexibly by setting controlled variable Q INT which improved the adaptability of the tiltmeter to different lighting levels.

A novel model method for III–V HEMTs small-signal model parameter extraction is presented in this work. All the model elements are directly derived from hot S-parameters, rather than cold S-parameters, by using vector fitting (VF) method The model renders excellent agreement with the measured and simulated data over 1 to 100 GHz, for a 2×150µm GaAs HEMT device manufactured in CETC-55 150nm GaAs pHEMT technology.

Design and characterization of a G-band (140–220 GHz) terahertz monolithic integrated circuit (TMIC) amplifier in eight-stage common-emitter topology are performed based on the 0.5-μm InGaAs/InP double heterojunction bipolar transistor (DHBT). An inverted microstrip line is implemented to avoid a parasitic mode between the ground plane and the InP substrate. The on-wafer measurement results show that peak gains are 20 dB at 140 GHz and more than 15-dB gain at 140–190 GHz respectively. The saturation output powers are −2.688 dBm at 210 GHz and −2.88 dBm at 220 GHz, respectively. It is the first report on an amplifier operating at the G-band based on 0.5-μm InP DHBT technology. Compared with the hybrid integrated circuit of vacuum electronic devices, the monolithic integrated circuit has the advantage of reliability and consistency. This TMIC demonstrates the feasibility of the 0.5-μm InGaAs/InP DHBT amplifier in G-band frequencies applications.

The frequency stabilities of InP DHBTs in a broadband over 1 to 220 GHz are investigated. A hybrid π-topology small-signal model is used to accurately capture the parasitics of devices. The model parameters are extracted from measurements analytically. The investigation results show that the excellent agreement between the measured and simulated data is obtained in the frequency range 200 MHz to 220 GHz. The dominant parameters of the π-topology model, bias conditions and emitter area have significant effects on the stability factor K. The HBT model can be unconditionally stable by reasonable selection of the proper bias condition and the physical layout of the device.

A common-base four finger InGaAs/InP double heterostructure bipolar transistor (DHBT) has been designed and fabricated using triple mesa structure and planarization technology. All processes are on 3-inch wafers. The area of each emitter finger is 1 × 15 μm2. The maximum oscillation frequency (fmax) is 325 GHz and the breakdown voltage BVCBO is 10.6 V, which are to our knowledge both the highest fmax and BVCBO ever reported for InGaAs/InP DHBTs in China. The high speed InGaAs/InP DHBT with a high breakdown voltage is promising for submillimeter-wave and THz electronics.

Based on the hydrogen-terminated surface channel diamond material, a 1 μm gate length diamond metal—insulator—semiconductor field-effect transistor (MISFET) was fabricated. The gate dielectric A12O3 was formed by naturally oxidated thin Al metal layer, and a less than 2 pA gate leakage current was obtained at gate bias between −4 V and 4 V. The DC characteristic of the diamond MISFET showed a drain-current density of 80 mA/mm at drain voltage of −5 V, and a maximum transconductance of 22 mS/mm at gate—source voltage of −3 V. With the small signal measurement, a current gain cutoff frequency of 2.1 GHz was also obtained.

usc Refereed/Peer-reviewed This paper proposes a robust real-time face recognition system that utilizes regression tree based method to locate the facial feature points. The proposed system finds the face region which is suitable to perform the recognition task by geometrically analyses of the facial expression of the target face image. In real-world facial recognition systems, the face is often cropped based on the face detection techniques. The misalignment is inevitably occurred due to facial pose, noise, occlusion, and so on. However misalignment affects the recognition rate due to sensitive nature of the face classifier. The performance of the proposed approach is evaluated with four benchmark databases. The experiment results show the robustness of the proposed approach with significant improvement in the facial recognition system on the various size and resolution of given face images.