System engineering practices for complex systems and networks now require that requirement, architecture, and concept of operations product development teams, simultaneously harmonize their activities to provide timely, useful and cost-effective products. When dealing with complex systems of systems, traditional systems engineering methodology quickly falls short of achieving project objectives. This approach is encumbered by the use of a number of disparate hardware and software tools, spreadsheets and documents to grasp the concept of the network design and operation. In case of NASA's space communication networks, since the networks are geographically distributed, and so are its subject matter experts, the team is challenged to create a common language and tools to produce its products. Using Model Based Systems Engineering methods and tools allows for a unified representation of the system in a model that enables a highly related level of detail. To date, Program System Engineering (PSE) team has been able to model each network from their top-level operational activities and system functions down to the atomic level through relational modeling decomposition. These models allow for a better understanding of the relationships between NASA's stakeholders, internal organizations, and impacts to all related entities due to integration and sustainment of existing systems. Understanding the existing systems is essential to accurate and detailed study of integration options being considered. In this paper, we identify the challenges the PSE team faced in its quest to unify complex legacy space communications networks and their operational processes. We describe the initial approaches undertaken and the evolution toward model based system engineering applied to produce Space Communication and Navigation (SCaN) PSE products. We will demonstrate the practice of Model Based System Engineering applied to integrating space communication networks and the summary of its results and impact. We will highlight the insights gained by applying the Model Based System Engineering and provide recommendations for its applications and improvements.

关键词：空间通信；通信网络;系统工程；数据整合；系统集成

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When a fossil fuel is burned, oxygen in the air chemically reacts with combustible elements of the fuel to produce heat. Since nitrogen is nearly inert, it is mainly a diluent that carries away some of the energy released during the combustion process and produces pollutants. Oxygen-enhanced combustion has been considered as an attractive alternative in order to increase efficiency, to reduce volume of the flue gas, to lower emissions of NO_x and CO_2, and to improve heat transfer and flame stability characteristics. With decreasing costs involved in production of oxygen from air, oxygen-enhanced combustion may not only be limited to glass-melting and steel-making furnaces but also may have potential in the power-generation industry using fossil fuels such as coal and natural gas. Substantial research has been conducted to evaluate the effects of oxygen enrichment on overall efficiency, fuel savings, heat transfer rates, and pollutant emissions.

关键词：钢铁；矿物燃料；熔化；稀释剂

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Action cameras are used to capture extreme action sports or activities. They can capture highspeed and high-quality images.

关键词：操作相机；捕捉极端；行动运动；活动；动作摄像机

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For this study, a novel optical fiber sensing system was developed and tested for the monitoring of corrosion in transportation systems. The optical fiber sensing system consists of a reference long period fiber gratings (LPFG) sensor for corrosive environmental monitoring and a LPFG sensor coated with a thin film of nano iron and silica particles for steel corrosion monitoring. The environmental effects (such as pH and temperature) are compensated by the use of the reference LPFG sensor. The sensor design, simulation, and experimental validation were performed in this study to investigate the feasibility of the proposed sensing system for corrosion and environment monitoring. The detailed investigations of the proposed sensing system showed that within the detection limitation of the thin coated layer, the proposed sensor could monitor both the initial and stable corrosion rate consistently. Compared to the traditional electrochemical method, the proposed optical fiber sensing system has a converter coefficient of 1 nm/day=3.746(10-3 A/cm2). Therefore, the proposed nano iron/silica particles dispersed polyurethane coated optical fiber sensor can monitor the critical corrosion information of the host members in real time and remotely. With multiple LPFGs in a single fiber, it is possible to provide a cost-effective, distributed monitoring solution for corrosion monitoring of large scale transportation structures.

关键词：光纤;交通系统;环境影响

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A drive is an adjustable speed device that regulates the speed and direction of motors. Adjustment is done by varying the current flow through the motor. Drives are classified into two broad categories based on the type of current: AC drives and DC drives. AC drives are used to control AC electric motors, while DC drives are used for DC electric motors. Drives are widely used in manufacturing industries to regulate and control electrical devices such as fans,conveyors, machine spindles, and pumps. AC drives are widely used in process industries to increase the energy efficiency of motors.

关键词：驱动；调节电机；速度；方向；调速装置；交流驱动器；直流驱动器

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Wireless Body Area Networks (WBANs) are expected to promote new applications for the ambulatory health monitoring of chronic patients and the elderly population, aiming to improve their quality of life and independence. These networks are composed by wireless sensor nodes that measure physiological variables and transmit it, for example, to the patients' smartphone, which may acts as a gateway to a remote medical assistance service. A key element of such sensor nodes is the wireless transceiver as it often dominates the overall power budget. Therefore, to provide a high degree of energy autonomy, wireless transceivers with an ultra low power consumption are needed. In this book, a transceiver architecture and implementation is presented, which targets such highly power constrained applications and employs the Bluetooth low energy standard.

关键词：无线体域网；智能；无线收发器；功耗

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In fault diagnosis of circuit,fault diagnosis system using multi-sensor data fusion may not give reliable fault diagnosis result in cases when processing on inconsistent data carry inconsistent.In order to deal with such problems,This paper has developed an analog-circuit fault diagnostic system based on transferable belief model (TBM) and K-nearest neighbor rule from TBM.The proposed system has the capability to detect and identify fault components in an analog electronic circuit by analyzing its working temperature and testable voltage.Using K-nearest neighbor(KNN) rule to process the working temperature of component drastically enhances the testable information for fault detect,satisfying the need of fusing data from distinct evidence sources.The experimental results show that this system performs significantly better in fault diagnosis of analog circuits due to the proposed techniques.

关键词：模拟电路;故障诊断;故障定位;数据融合

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In order to obtain maximum battery lifetime and efficient operation, rechargeable batteries require unique charging profiles with an end-state, low current trickle charge. The series loaded resonant (SLR) charging system presented in this thesis meets the needs of an efficient, sensor integrated, and galvanically isolated trickle charger. The SLR DC-DC converter was successfully modeled in Simulink, and simulation results are verified in a laboratory application. The Simulink model and hardware are tested at several operating points. Component stresses are quantified and weak points are identified.

关键词：电池充电器,转换器;蓄电池;直流对直流转换器;电动电池

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The main objective of the proposed work is to determine the efficacy of distributed fiber-optic sensing in the form of Brillouin Optical Time Domain Reflectometry/Analysis (BOTDR/BOTDA) and/or fiber Bragg grating (FBG) application to measure and model the spatial and temporal distribution of dynamic strains in a bed of manufactured clay in response to an applied impact load at its surface.

关键词：光纤;数值分析;冲击波,冲击载荷;空间分布

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This paper investigates the implementation of compressive sensing (CS) for handheld GPR sensor system for landmine detection. The system collects GPR data in random and sparse spatial positions, resulting in the limited resolution of the GPR image. Compressive sensing which is widely known to be able to reconstruct sparse information from limited number of measurements is applied for this system. In this study, we present landmine detection by model based CS that exploit the physical characteristic of the landmine in CS processing. The performance is evaluated using real data sets acquired in a landmine field in Cambodia. The results show that the model based CS is able to give better visualization of a buried PMN-2 landmine compared to the conventional CS processing. It is also observed that the accuracy of the block sparsity level, which is the estimation of how many targets exist in the area, is an important factor for the correct image reconstruction by the model based CS.

关键词：压缩传感;探地雷达;地雷;GPR

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