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1.
Ten pistachio samples from various Iranian cultivars were examined for some botanical features of their nuts and oil characteristics of their kernels. The wt of 100 nuts varied from 78.5 to 136.9 g. The nuts contained 44.1–58.9% kernel. Moisture of the kernels was low, 2.5–4.1%, and the kernels contained 55.2–60.5% oil. Unsaponifiable matter (0.72–0.96%), saponification value (189.0–193.6), refractive index (1.4635–1.4643), and iodine value (98.1–100.5) showed little differences in various samples. Fatty acids detectable by gas chromatographic analysis were: traces of myristic; 9.2–13.4%, palmitic; 0.5–1.1%, stearic; traces of arachidic; 0.5–1.0%; palmitoleic; 56.1–64.0%, oleic; 22.6–31.0%, linoleic; and 0.1–0.4%, linolenic. There were no significant differences due to origin and/or cultivar of the samples.  相似文献   
2.
The current study is focused to analyze the heat transfer characteristics in a porous duct. The mathematical model of heat transfer in a porous duct was solved by converting the governing partial differential equations into a set of algebraic equations with the help of finite element method. A simple three noded triangular element is used to mesh the duct domain. The current problem consists of a square duct with outer walls being exposed to hot temperature Th, and inner walls subjected to cool temperature Tc. Emphasis is given to investigate the effect of width ratio of cavity on heat and fluid flow characteristics inside the porous medium. The results are reported for various duct width ratios, Rayleigh number etc. It is found that the Nusselt number increases with increase in height of cavity along the vertical walls of duct; however the Nusselt number for certain values of duct ratio oscillates along the width of the porous medium at bottom wall of the cavity.  相似文献   
3.
In this article we introduce CONNECT, an infrastructure running on small wireless devices (e.g., PDA phones) and servers that aids people with disabilities in leading their everyday lives. We refer to the target (client) devices as personal portable devices (PPDs). The architecture of the CONNECT system is described, with emphasis on the accessibility services provided to its clients. As an example, the reminder service of CONNECT is profiled where care providers and community organizers (or general users who have appropriate rights) can send timely reminders to the PPD owners, giving them a chance to respond to these messages. In conjunction with the connect project, 600 PPDs are deployed to people with disabilities for evaluation purposes.  相似文献   
4.
This paper describes research towards a system for locating wireless nodes in a home environment requiring merely a single access point. The only sensor reading used for the location estimation is the received signal strength indication (RSSI) as given by an RF interface, e.g., Wi-Fi. Wireless signal strength maps for the positioning filter are obtained by a two-step parametric and measurement driven ray-tracing approach to account for absorption and reflection characteristics of various obstacles. Location estimates are then computed using Bayesian filtering on sample sets derived by Monte Carlo sampling. We outline the research leading to the system and provide location performance metrics using trace-driven simulations and real-life experiments. Our results and real-life walk-troughs indicate that RSSI readings from a single access point in an indoor environment are sufficient to derive good location estimates of users with sub-room precision. Gergely V. Záruba is an Assistant Professor of Computer Science and Engineering at The University of Texas at Arlington (CSE@UTA). He has received the Ph.D. degree in Computer Science from The University of Texas at Dallas in 2001, and the M.S. degree in Computer Engineering from the Technical University of Budapest, Department of Telecommunications and Telematics, in 1997. Dr. Záruba’s research interests include wireless networks, algorithms, and protocols, performance evaluation, current wireless and assistive technologies. He has served on many organizing and technical program committees for leading conferences and has guest edited journals. He is a member of the IEEE and its Communications Society. Manfred Huber is an Assistant Professor of Computer Science and Engineering at The University of Texas at Arlington (CSE@UTA). He received his M.S. and Ph.D. degrees in Computer Science from the University of Massachusetts, Amherst in 1993 and 2000, respectively. He obtained his “Vordiplom” from the University of Karlsruhe, Germany in 1990. Dr. Huber is the co-director of the Robotics and of the Learning and Planning Laboratory at CSE@UTA. His research interests are in reinforcement learning, autonomous robots, cognitive systems, and adaptive human-computer interfaces. He is a member of the IEEE, the ACM, and the AAAI. Farhad A. Kamangar is a Professor of Computer Science and Engineering at The University of Texas at Arlington (CSE@UTA). He has received the Ph.D. and M.S. degrees in Electrical Engineering from The University of Texas at Arlington in 1980 and 1977 respectively. He received his B.S. degree from the University of Teheran, Iran in 1975. Dr. Kamangar’s research interests include image processing, robotics, signal processing, machine intelligence and computer graphics. He is a member of the IEEE and the ACM. Imrich Chlamtac is the President of CREATE-NET and the Bruno Kessler Professor at the University of Trento, Italy and has held various honorary and chaired professorships in USA and Europe including the Distinguished Chair in Telecommunications Professorship at the University of Texas at Dallas, Sackler Professorship at Tel Aviv University and University Professorship at the Technical University of Budapest. In the past he was with Technion and UMass, Amherst, DEC Research. Dr. Imrich Chlamtac has made significant contribution to various networking technologies as scientist, educator and entrepreneur. Dr. Chlamtac is the recipient of multiple awards and recognitions including Fellow of the IEEE, Fellow of the ACM, Fulbright Scholar, the ACM Award for Outstanding Contributions to Research on Mobility and the IEEE Award for Outstanding Technical Contributions to Wireless Personal Communications. Dr. Chlamtac published close to four hundred refereed journal, book, and conference articles and is listed among ISI’s Highly Cited Researchers in Computer Science. Dr. Chlamtac is the co-author of four books, including the first book on Local Area Networks (1980) and the Amazon.com best seller and IEEE Editor’s Choice Wireless and Mobile Network Architectures, published by John Wiley and Sons (2000). Dr. Chlamtac has widely contributed to the scientific community as founder and Chair of ACM Sigmobile, founder and steering committee chair of some of the lead conferences in networking, including ACM Mobicom, IEEE/SPIE/ACM OptiComm, CreateNet Mobiquitous, CreateNet WiOpt, IEEE/CreateNet Broadnet, IEEE/CreateNet Tridentcom and IEEE/CreateNet Securecomm conferences. Dr. Chlamtac also serves as the founding Editor in Chief of the ACM/URSI/Springer Wireless Networks (WINET), the ACM/Springer Journal on Special Topics in Mobile Networks and Applications (MONET).  相似文献   
5.
The current study is focused to investigate the natural convective heat transfer characteristics in a porous square annulus. Finite element method is used as a tool to simplify the partial differential equations that govern the heat and fluid flow characteristics inside the porous medium. A simple three noded triangular element is used to divide the porous domain into smaller segments known as elements. The algebraic set of equations resulting from the finite element equation are assembled into a global matrix and then solved iteratively to get the solution variables. Thermal equilibrium as well as non equilibrium in porous domain is considered. The effect of various geometric and physical parameters are investigated. The boundary conditions are such that the inner walls of the annulus are heated isothermally to temperature Th, and the outer surfaces are exposed to cool temperature Tc. The width ratio defined as the ratio of hollow portion to the length of the cavity is varied from 0.125 to 0.875. Results are discussed with respect to width ratio, Rayleigh number, radiation parameter and viscous dissipation parameter.  相似文献   
6.
This study deals with the preparation of activated carbon (CDSP) from date seed powder (DSP) by chemical activation to eliminate polyaromatic hydrocarbon—PAHs (naphthalene—C10H8) from synthetic wastewater. The chemical activation process was carried out using a weak Lewis acid of zinc acetate dihydrate salt (Zn(CH3CO2)2·2H2O). The equilibrium isotherm and kinetics analysis was carried out using DSP and CDSP samples, and their performances were compared for the removal of a volatile organic compound—naphthalene (C10H8)—from synthetic aqueous effluents or wastewater. The equilibrium isotherm data was analyzed using the linear regression model of the Langmuir, Freundlich and Temkin equations. The R2 values for the Langmuir isotherm were 0.93 and 0.99 for naphthalene (C10H8) adsorption using DSP and CDSP, respectively. CDSP showed a higher equilibrium sorption capacity (qe) of 379.64 µg/g. DSP had an equilibrium sorption capacity of 369.06 µg/g for C10H8. The rate of reaction was estimated for C10H8 adsorption using a pseudo-first order, pseudo-second order and Elovich kinetic equation. The reaction mechanism for both the sorbents (CDSP and DSP) was studied using the intraparticle diffusion model. The equilibrium data was well-fitted with the pseudo-second order kinetics model showing the chemisorption nature of the equilibrium system. CDSP showed a higher sorption performance than DSP due to its higher BET surface area and carbon content. Physiochemical characterizations of the DSP and CDSP samples were carried out using the BET surface area analysis, Fourier-scanning microscopic analysis (FSEM), energy-dispersive X-ray (EDX) analysis and Fourier-transform spectroscopic analysis (FTIR). A thermogravimetric and ultimate analysis was also carried out to determine the carbon content in both the sorbents (DSP and CDSP) here. This study confirms the potential of DSP and CDSP to remove C10H8 from lab-scale synthetic wastewater.  相似文献   
7.
OBJECTIVES: To assess the likelihood of health care legislation in the forthcoming 105th Congress in 5 areas: health care coverage, tax and Employee Retirement Income Security Act (ERISA) policy, Medicaid, Medicare, and managed care. DESIGN: Informal, semistructured conversations that took place in the months prior to the 1996 elections. POPULATION: Congressional health staff and administration officials. OUTCOME MEASURES: Unofficial, off-the-record personal opinions. RESULTS: Health care coverage initiatives to benefit children and unemployed persons are likely to be proposed, but have little chance of enactment; children are seen as well provided for under current Medicaid law, the strong economy and high employment levels lower concern for unemployed issues, and the effort required to pass the Kassebaum-Kennedy legislation needs time to settle. Tax proposals, such as medical savings accounts (MSAs), and ERISA amendments have no constituency; also, the MSA demonstration in Kassebaum-Kennedy will forestall further action. Medicaid is far less an issue than in the previous Congress, because spending has fallen unexpectedly, the bitter fight over block grants makes them unlikely to be revisited, and the administration is likely to enhance state flexibility through waivers. Medicare will be the subject of substantial action to defer impending insolvency temporarily, but there is virtually no chance that definitive long-term solutions will be enacted even though the underlying fiscal problems are thoroughly understood and recognized. Managed care will be the venue for numerous proposals designed to address specific consumer and quality issues. CONCLUSIONS: Four bitter years of fighting over health care issues has raised awareness of the problems, but has produced a political chemistry that is too rancorous to permit passage of significant legislation in the near future.  相似文献   
8.
Hybrid coding of color television images at broadcast standards is investigated. This involves two-dimensional discrete cosine transform (2-D DCT) of each field, followed by the differential pulse code modulation (DPCM) between successive fields. Two 22frame sequences of "Water Skier" and "Wheel of Fortune" in component form, i.e., luminanceYand chrominanceIandQ, were utilized as the database. A statistical study of the prediction error in the 2-D DCT domain is carried out. Three different algorithms for the 2-D DCT system are simulated and analyzed. In the first algorithm, optimum (nonuniform) quantizers are used in DPCM loops followed by fixed-wordlength coders. Uniform quantizers along with variablewordlength coders are implemented in the second system. The performances of different deterministic coders are investigated and compared with Huffman coders. The third scheme is an adaptive system. In this system each 8 × 8 block is divided into four subblocks. The activity of each subblock is monitored and when it exceeds some threshold, the subblock is considered to be spatially active. More bits are assigned to active subblocks and the ranges of corresponding quantizers are expanded. The prediction error of the dc coefficient is monitored to determine the temporal activity of a block. For a temporally active block, the number of bits assigned to the two lower frequency subblocks is increased. Performance of these three systems for unmatched statistics and in the case of a scene change are studied. Mean square error (MSE) between the original and reconstructed images, bit rate, entropy, essential maximum, and other parameters are utilized as the performance criteria. Also, a subjective evaluation of the processed images is carried out. It is shown that the interfield adaptive hybrid coding of color TV signals in component form results in significant savings in bit rates for transmission over a digital link.  相似文献   
9.
Pervasive computing is an emerging technology that offers new possibilities to distributed computing and computer networking; it employs a wide variety of smart, ubiquitous devices throughout an individual's working and living environment. Mobile agents are software entities that can migrate between servers (mobile agent environments) of the network accomplishing various tasks on the behalf of their owners. The objective of this paper is to describe a test and prototyping environment for experimenting with mobile agents in pervasive environments. A prototype environment for a novel, proactive infrastructure is described for mobile agent assisted pervasive computing. In addition, a new message passing algorithm is provided for mobile agent connection establishment and management (CEMA). Simulation results show the performance of the proposed approach.  相似文献   
10.
This paper reports on the status of The University of Texas at Arlington student effort to design, build and fly an Autonomous Aerial Vehicle. Both the 1991 entry into the First International Aerial Robotics Competition as well as refinements being made for 1992 are described. Significant technical highlights include a real-time vision system for target objective tracking, a real-time ultrasonic locator system for position sensing, a novel mechanism for gradually moving from human to computer control, and a hierarchical control structure implemented on a 32-bit microcontroller. Detailed discussion about the design of multivariable automatic controls for stability augmentation is included. Position and attitude control loops are optimized according to a combined 2 and criteria. We present a modification of a recently published procedure for recovering a desired open-loop transfer function shape within the framework of the mixed 2/ problem. This work has led to a new result that frees a design parameter related to imposing the constraint. The additional freedom can be used to improve upon the performance and robustness characteristics of the system.  相似文献   
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