Magnetic sensitivity technology based on microwave modulation of solid state spin system NV center

In view of the low resolution and accuracy of traditional magnetometer,a method of microwave frequency modulation technology based on nitrogen-vacancy(NV)center in diamond for magnetic detection was proposed.The magnetometer studied can reduce the frequency noise of system and improve the magnetic sensitivity by microwave frequency modulation.Firstly,ESR spectra by sweeping the microwave frequency was obtained.Further,the microwave frequency modulated was gained through the mixed high-frequency sinusoidal modulation signal generated by signal generator.In addition,the frequency through the lock-in amplifier was locked,and the signal which was proportional to the first derivative of the spectrum was obtained.The experimental results show that the sensitivity of magnetic field detection can reach 17.628 nT/Hz based on microwave frequency modulation technology.The method realizes high resolution and sensitivity for magnetic field detection.

Fabrication of 32 Gb/s Electroabsorption Modulated Distributed Feedback Lasers by Selective Area Growth Technology

A 32 Gb/s monolithically integrated electroabsorption modulated laser is fabricated by selective area growth technology. The threshold current of the device is below 13mA. The output power exceeds 10mW at 0V bias when the injection current of the distributed feedback laser is 100mA at 25℃. The side mode suppression ratio is over 50 dB. A 32Gb/s eye diagram is measured with a 3.SVpp nonreturn-to-zero pseudorandom modulation signal at -2.3 V bias. A clearly opening eyediagram with a dynamic extinction ratio of 8.01 dB is obtained.

A new tracking error detection method using amplitude difference detection for signal waveform modulation multi-level discs

The sub-land/sub-pit affects the characteristic of the tracking error signal which is generated by the conventional differential phase detection （DPD） method in the signal waveform modulation multi-level （SWML） read-only disc. To solve this problem, this paper proposes a new tracking error detection method using amplitude difference. Based on the diffraction theory, the amplitude difference is proportional to the tracking error and is feasible to be used for obtaining the off-track information. The experimental system of the amplitude difference detection method is developed. The experimental results show that the tracking error signal derived from the new method has better performance in uniformity and signal-to-noise ratio than that derived from the conventional DPD method in the SWML read-only disc.

Controlling the light wavefront through a scattering medium based on direct digital frequency synthesis technology

Phase modulation is a crucial step when the frequency-based wavefront optimization technique is exploited to measure the optical transmission matrix(TM) of a scattering medium. We report a simple but powerful method, direct digital frequency synthesis(DDS) technology to modulate the phase front of the laser and measure the TM. By judiciously modulating the phase front of a He–Ne laser beam, we experimentally generate a high quality focus at any targeted location through a 2 mm thick 120 grit ground glass diffuser, which is commercially used in laser display and laser holographic display for improving brightness uniformity and reducing speckle. The signal to noise ratio(SNR) of the clear round focus is 50 and the size is about 44 μm. Our study will open up new avenues for enhancing light energy delivery to the optical engine in laser TV to lower the power consumption, phase compensation to reduce the speckle noise, and controlling the lasing threshold in random lasers.

Role of PV-Powered Vehicles in Low-Carbon Society and Some Approaches of High-Efficiency Solar Cell Modules for Cars

Development of highly-efficient photovoltaic (PV) modules and expanding its application fields are significant for the further development of PV technologies and realization of innovative green energy infrastructure based on PV. Especially, development of solar-powered vehicles as a new application is highly desired and very important for this end. This paper presents the impact of PV cell/module conversion efficiency on reduction in CO2 emission and increase in driving range of the electric based vehicles. Our studies show that the utilization of a highly-efficient (higher than 30%) PV module enables the solar-powered vehicle to drive 30 km/day without charging in the case of light weight cars with electric mileage of 17 km/kWh under solar irradiation of 3.7 kWh/m2/day, which means that the majority of the family cars in Japan can run only by the sunlight without supplying fossil fuels. Thus, it is essential to develop high-efficiency as well as low-cost solar cells and modules for automotive applications. The analytical results developed by the authors for conversion efficiency potential of various solar cells for choosing candidates of the PV modules for automotive applications are shown. Then we overview the conversion efficiency potential and recent progress of various Si tandem solar cells, such as III-V/Si, II-VI/Si, chalcopyrite/Si, and perovskite/Si tandem solar cells. The III-V/Si tandem solar cells are expected to have a high potential for various applications because of its high conversion efficiency of larger than 36% for dual-junction and 42% for triple-junction solar cells under 1-sun AM1.5 G illumination, lightweight and low-cost potentials. The analysis shows that III-V based multi-junction and Si based tandem solar cells are considered to be promising candidates for the automotive application. Finally, we report recent results for our 28.2% efficiency and Sharp’s 33% mechanically stacked InGaP/GaAs/Si triple-junction solar cell. In addition, new approaches which are suitable for automotive applications by using III-V triple-junction, and static low concentrator PV modules are also presented.

Intrusion Detection System with Remote Signalling for Vehicles Using an Arduino Controller and Radio-Frequency Technology

Malicious activities or policy violations have been a concern for the past years. For example, many people have been victims of robbery on vehicles. A conceptual diagram of an Intrusion Detection System (IDS) [1] [2] for vehicles with remote signaling using an Arduino controller and radio-frequency technology is proposed in this paper. To address malicious activities on vehicles, two aspects are considered here, namely: notifier and detector. Firstly, an object-oriented C module that puts on and off a controller (installed inside the vehicle) and an anti-theft electronic editing that powered using an alternator and supported by a back-up battery are implemented. Secondly, a magnetic intrusion sensor, controlled by a proximity detector using radio-frequency technology, has been installed on each vehicle door. To enable IDS, a user needs to activate the monitoring system when leaving their vehicle. This is done using a remote system. In case the user does not activate the monitoring system while leaving the vehicle, a 5-meter-proximity detector will automatically lock the system and set off the monitoring system whenever the user is outside the detection zone. The detection zone is a 5-meter radius area centered at the controller. Here, monitoring consists of geolocating any intruders within the detection zone. This means, if any of the vehicle doors is opened while the system is still locked, the controller will activate the vehicle alarm for a few seconds, thereafter send an SMS notification to the owner. The system automatically unlocks as soon as the proximity detector is within the detection zone. The contribution of this paper, as compared to other similar work, is to reinforce the electronic implementation of IDS.

Chinese Telemetry Technology under Fast Development

The history of the development of Chinese telemetry is introduced in the paper. The new telemetry ground station and the new onboard space telemetry system, with the idea of systematic design and the specification, are described.

Modulation Index Estimation of Frequency and Phase Modulated Signals

Modulation index estimation is important in the demodulation and recognition of Angle Modulation (AM) signals which include Frequency Modulation (FM) and Phase Modulation (PM) signals. In this paper, we firstly analyzed the AM signals with baseband modulation types, such as monotone, PSK, FSK, in the time and frequency domain. Then, we established a unified mathematical representation for the AM signals. Finally, we derived a blind estimation algorithm for the modulation index without using any prior knowledge. Simulation results verify the capabilities of the proposed algorithm.

A KIND OF PAPR REDUCTION METHOD BASED ON PRUNING WPM AND PTS TECHNOLOGY

Wavelet packet multicarrier system gains widespread concern because of its better resistance performance to Inter-Symbol Interference (ISI) and Inter-Carrier Interference (ICI), as well as the higher spectrum efficiency. However, multicarrier system has a high Peak to Average Power Ratio (PAPR), which will lead to many problems such as lower system performance. In order to solve the problem, a kind of PAPR reduction method based on pruning Wavelet Packet Modulation (WPM) and Partial Transmit Sequences (PTS) technology is proposed in this paper, through proper pruning of the full-tree structure of wavelet packet modulation in the PTS technology to reduce the number of nodes in the system, and finally improve the reduction effect of PAPR. Simulation results show that when Complementary Cumulative Distribution Function (CCDF) is 10 -3 , PTS based on pruning WPM compared with PTS technique and pruning technique has improved about 1 dB and 1.5 dB, which will not affect the system's Bit Error Rate (BER) performance in the wavelet packet multicarrier system.

Research on Feature Extraction of Composite Pseudocode Phase Modulation-Carrier Frequency Modulation Signal Based on PWD Transform

The identification features of composite pseudocode phase modulation and carry frequency modulation signal include pseudocode and modulation frequency. In this paper,PWD is used to extract these features. First,the feature of pseudocode is extracted using the amplitude output of PWD and the correlation filter technology. Then the feature of frequency modulation is extracted by way of PWD analysis on the signal processed by anti-phase operation according to the extracted feature of pseudo code,i.e. position information of changed abruptly point of phase. The simulation result shows that both the features of frequency modulation and phase change position caused by the pseudocode phase modulation can be extracted effectively for SNR=3 dB.

Emergency Housing Solutions after Earthquakes:Innovative Technologies and Resilience Strategies

The international research project,developed through the collaboration between the University of Chieti and Pescara“G.d'Annunzio”and theÉcole Nationale d'Architecture of Marrakech,aims to explore new strategies for emergency housing,with a focus on technological innovation and the resilience of temporary shelters.The main goal of the research is to define a more efficient housing module for post-earthquake scenarios,based on the analysis of the most advanced international solutions for first-response shelters.This study has made it possible to identify both the strengths and weaknesses of existing proposals,leading to the development of a housing model capable of improving living conditions during emergency phases.The objective is to propose an innovative housing module that not only addresses immediate post-disaster needs but is also adaptable to the specific socio-cultural characteristics of the affected populations.As a result of this work,the“DIVA-Variable Dimension Emergency Shelter”project was developed.This housing model stands out for its ability to adapt to the needs of different emergency phases,offering a versatile and customizable solution that effectively addresses post-earthquake challenges while ensuring respect for cultural specificities and improving quality of life.

CMOS Quadrature Modulator and Up-Conversion Mixer for 802.11a Wireless LAN Systems

A quadrature modulator and an up-conversion mixer for an 802. lla wireless LAN system are designed and fabricated in 0.18μm gate length standard CMOS technology. A current feedback loop with a transconductor is used to improve the linearity of the quadrature modulator;An LC resonant tank is used as the load of the upconversion mixer to improve its gain and increase the voltage swing. The measurement results show that the input P1dB achieves -3.6dBm, the transducer power gain of the circuit is -3.6dB,and the current consumes about 45.8mA with a 1.8V power supply.

Conductivity modulation enhanced lateral IGBT with SiO_2 shielded layer anode by SIMOX technology on SOI substrate

A new lateral insulated-gate bipolar transistor（LIGBT） with a SiO_2 shielded layer anode on SOI substrate is proposed and discussed.Compared to the conventional LIGBT,the proposed device offers an enhanced conductivity modulation effect due to the SiO_2 shielded layer anode structure which can be formed by SIMOX technology.Simulation results show that,for the proposed LIGBT,during the conducting state,the electron-hole plasma concentrations in the n-drift region are several times larger than those of the conventional LIGBT;the conducting current is up to 37% larger than that of the conventional one.The enhanced conductivity modulation effect by SiO_2 shielded layer anode does not sacrifice other characteristics of the device,such as breakdown and switching,but is compatible with other optimized technologies.

The Transplant of Technology of Capacitive Displacement Transducer to Phase Modulation Grating-the Research of the Grating with nm Measuring Resolution

The method rising measuring resolution through reducing pitch of the transducer has brought forward from the basic structure, principle and the corresponding relationship among pitches of capacitive electrodes, period T and phase shift of vv(x,t). But if the traditional technique of PCB made of the transducer is still used, it will meet with difficulties in lead wire. And so the technology transplant from the transducer to grating is presented, the basic principle of the phase modulation grating similar...

HIGH-EFFICIENCY CODING FOR PAL COLOR TELEVISION SIGNAL

Proceeding from the specific characteristics of PAL television signals adopted in China this paper points out that if the fs = 2fsc of sub-Nyquist sampling and DPCM encoding is used for PAL complete signal and if the blanking time is utilized to transmit code of effective area, it is possible to transmit a color TV signal over PCM three-group channel.

光伏组件技术进步的“干中学”与“研中学”效应研究

光伏产业是我国具有全球竞争优势的战略性新兴产业,推动其高质量发展是实现“3060”双碳目标的重要手段之一。采用双因素学习曲线模型,参照索罗余值法测度从2015—2020年光伏组件技术进步的“干中学”效应和“研中学”效应。其中,由“干中学”效应导致的光伏组件成本下降约为0.85元/瓦,贡献率为42.40%;由“研中学”效应导致的成本下降约为1.07元/瓦,贡献率为57.60%。进一步对光伏组件“干中学”效应和“研中学”效应的驱动因素进行研究。“干中学”效应方面,从供给侧和需求侧两个维度采用文献分析法讨论了驱动光伏组件产量增加的因素;“研中学”效应方面,采用知识生产函数分析研发资本投入和人力投入对光伏组件技术进步速度的影响。结果表明,光伏组件研发资本投入存在边际报酬递减的现象,而研发人力投入的边际报酬是递增的。在此基础上,分析研究结果的政策启示。

Reviewer Locator模块在科技期刊中的应用实践与发展前景——以《中国肺癌杂志》为例

科技期刊作为科技传播的重要力量,其对重要科研成果的发布速度影响着科学技术的传播效力,而编辑工作效率直接决定稿件发表周期,提高编辑工作效率是科技期刊发展的推进器。为此,从同行评议审稿人储备和遴选方面入手,重点阐述如何准确高效地多维度遴选优质审稿人,归纳并探析Reviewer Locator模块在科技期刊办刊工作中的实际应用经验,助力出版业实现质量更好、效率更高的发展。

一种L波段300W GaN脉冲功率模块

随着第三代半导体GaN器件技术的不断发展,GaN高电子迁移率晶体管(HEMT)在电子系统中逐步得到了广泛应用。研制了一款小型化L波段300 W GaN脉冲功率模块。研发了满足高压脉冲工作条件的GaN HEMT芯片,采用负载牵引技术进行了器件大信号阻抗参数提取,并以此为基础设计了小型化匹配网络进行阻抗变换。基于高压驱动芯片和开关器件芯片设计了小型化高压脉冲调制电路。测试结果表明,在工作频率990~1130 MHz、工作电压50 V、脉冲宽度100μs、占空比10%下,功率模块脉冲输出功率大于300 W,功率附加效率大于53%,功率增益大于38 dB。功率模块尺寸为30 mm×30 mm×8 mm。

A Practical Online Approach to Protecting Kernel Heap Buffers in Kernel Modules

Heap overflow attack is one of the major memory corruption attacks that have become prevalent for decades. To defeat this attack,many protection methods are proposed in recent years. However,most of these existing methods focus on user-level heap overflow detection. Only a few methods are proposed for kernel heap protection. Moreover,all these kernel protection methods need modifying the existing OS kernel so that they may not be adopted in practice. To address this problem,we propose a lightweight virtualization-based solution that can protect the kernel heap buffers allocated for the target kernel modules. The key idea of our approach is to combine the static binary analysis and virtualization technology to trap a memory allocation operation of the target kernel module,and then add one secure canary word to the end of the allocated buffer. After that,a monitor process is launched to check the integrity of the canaries. The evaluations show that our system can detect kernel heap overflow attacks effectively with minimal performance cost.

基于半导体桥和含能材料的信息储存介质自毁模块研究

针对高安全等级信息储存介质硬件层面的防护,开展了基于半导体桥(SCB)和含能材料的低驱动能量自毁模块的研究.建立了SCB等离子体发火、能量传递、含能材料点火的数学模型并完成了理论计算,利用COMSOL搭建SCB多物理场仿真模型并校核其性能,搭建了试验平台并进行SCB与含能材料发火性能测试的试验.仿真和试验结果表明:含能自毁模块具有优良的发火性能,能在5 V充电电压的激励下,起爆SCB桥区并使桥区温度能在18μs内达到2700 K,从而激发0.43 mg叠氮化铜在50μs内起爆产生爆轰波.含能自毁模块能够完成能量的传递并摧毁目标信息储存介质,有效避免信息储存介质关键信息被窃取,保证了信息储存介质的安全性.