Garbage collection is widely used and has largely been a boon for programmer productivity. However, traditional garbage collection is approaching both practical and theoretical performance limits. In practice, the maximum heap size and heap structure of large applications are in uenced as much by garbage collector behavior as by resource availability.We include a discussion of the design trade-o s inherent in our approach, and lessons to be learned from our collectors. We close with a discussion of several design variants which we have not been able to explore in depth, but believe would be worthwhile to explore in future work.

关键词：释放提示；串行收集器；并行收集器；收集器算法；元数据

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Our capstone project is to build a mobile application on the Android platform that generates a house floor plan overlaid with Wi-Fi strength map. Right now in the market, there are plenty of mobile apps about measuring the floor plan or the WiFi signal strength, but there has not been an app that combines those two features. Since Wi-Fi is becoming the de facto standard for in-home wireless connectivity between devices inside the home, our industry partner, Qualcomm, thought this could be a great feature to be added to the floor plan app.

关键词：Wi-Fi强度；房子平面图；合作；安卓平台；移动应用

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This thesis considers the best use of network traffic data to increase cyber security. This operational problem is one of great concern to network administrators and users generally. Our specific task was performed for the Network Security Division of the Army Research Laboratory, who requested we analyze a dataset of cyber-attacks masked in a background of representative network traffic (the 'Skaion' dataset). We find that substantial preprocessing must done before statistical methods can be applied to raw network data, that no single predictor is sufficient, and that the most effective statistical analysis is logistic regression. Our approach is novel in that we consider not only single predictor events, but also combinations of reports from multiple tools. While we consider a number of different statistical techniques, we find that the most satisfactory model is based on logistic regression. Finally, we conclude that while the Skaion dataset is valuable in terms of its new approach to network traffic emulation, the 1999 KDD Cup and DARPA-MIT datasets-despite their many shortcomings-are more clearly organized and accessible to academic study. Cyber security is a globally important problem and datasets like Skaion's must maximize opportunities for cross-disciplinary academic endeavors.

关键词：电子信息；网络安全；数据集；统计分析

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This document describes a repeatable test procedure that attempts to simulate shading situations, as would be experienced by typical residential rooftop photovoltaic (PV) systems. This type of shading test is particularly useful to evaluate the impact of different power conversion setups, including microinverters, DC power optimizers and string inverters, on overall system performance. The performance results are weighted based on annual estimates of shade to predict annual performance improvement. A trial run of the test procedure was conducted with a side by side comparison of a string inverter with a microinverter, both operating on identical 8kW solar arrays. Considering three different shade weighting conditions, the microinverter was found to increase production by 3.7under light shading, 7.8under moderate shading, and 12.3under heavy shading, relative to the reference string inverter case. Detail is provided in this document to allow duplication of the test method at different test installations and for different power electronics devices.

关键词：电子信息；电子；光伏；模块级

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Wireless communications use radio waves as media to transmit information. Wireless network is an important portion of a communication system. In this chapter, we discuss security solutions for wireless networks. It is quite common that the wireless network serves as an access network to connect a communication node to a wired network using a radio technology such as cellular technology and the technology specified in IEEE 802.11, where the wireless link is the first hop and/or the last hop in a communication path as illustrated in Figure 10.1.

关键词：电子信息；网络安全；无线

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Site survey data for several residential installations are provided, showing the extent and frequency of shade throughout the year. This background information is used to design a representative shading test that is conducted on two side-by-side 8-kW photovoltaic (PV) installations. One system is equipped with a standard string inverter, while the other is equipped with microinverters on each solar panel. Partial shade is applied to both systems in a comprehensive range of shading conditions, simulating one of three shade extents. Under light shading conditions, the microinverter system produced the equivalent of 4annual performance improvement, relative to the string inverter system. Under moderate shading conditions, the microinverter system outperformed the string inverter system by 8, and under heavy shading the microinverter increased relative performance by 12. In all three cases, the percentage of performance loss that is recovered by the use of distributed power electronics is 40-50. Additionally, it was found that certain shading conditions can lead to additional losses in string inverters due to peak-power tracking errors and voltage limitations.

关键词：电子信息；电子；光伏系统；分布式

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In this chapter, we selected a few typical commercial power electronic controllers to illustrate their development and application in solving real-world problems. It is clear that, for different applications, the circuit topologies and controllers take different forms. Even for the same application with the same circuit topology, different controllers and methods are still used to achieve different performance and characteristics.

关键词：电子信息；电子；控制器；商业

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Bidirectional power electronics can add vehicle-to-grid (V2G) capability in a plug-in vehicle, which then allows the vehicle to operate as a distributed resource (DR). The uniqueness of the battery-based V2G power electronics requires a test procedure that will not only maintain IEEE interconnection standards, but can also evaluate the electrical performance of the vehicle working as a DR. The objective of this paper is to discuss a recently published NREL technical report that provides interim test procedures for V2G vehicles for their integration into the electrical distribution systems and for their performance in terms of continuous output power, efficiency, and losses. Additionally, some other test procedures are discussed that are applicable to a V2G vehicle that desires to provide power reserve functions. A few sample test results are provided based on testing of prototype V2G vehicles at NREL.

关键词：电子信息；电子；汽车电网；互联

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In this study a Linked Network Security system based on Virtualization (LNSV) is proposed to effectively perform data transmissions in a network separated environment under the aspects of management, operation, and cost. The LNSV proposed in this study represents an open architecture in accessing its system through network connectors for all users in individual networks and can be used as a general purposed system for storing all data to be transmitted. It is possible to prevent the access of unauthorized users because the stored data files include source IP/PORT, destination IP/PORT and Hash Values. Also, it can guarantee the security of communication through transmitting and receiving data using encryption/ decryption functions. Thus, the LNSV can provide safe connection services between separated networks.

关键词：电子信息；网络安全；系统；设计

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We have significant accomplishments on uncertainty quantification in inverse problems for dynamical systems, generalized sensitivity and optimal design of experiments, elasticity and viscoelasticity modeling for buried target detection, and general inverse problem methodology for proliferating populations. Our efforts have continued on development of efficient accurate integration of Fokker Planck equations. Our objective is to analyze and optimize the dynamic behavior of nonlinear stochastic differential equations, especially the stochastic resonance effects based on the probability density function generated by the Fokker Planck equation. Our approach uses the backward characteristic method and the time-splitting integration of the Fokker Planck equation.

关键词：电子信息；网络安全；福克-普朗克方程；不确定性

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