Nancy A.Feldman Nancy A.Feldman Nancy A.Feldman Nancy A.Feldman Nancy A.Feldman无法摆脱的电话困境

你打给供应商的下一个电话可能就是Max接听，这是一种全新的虚拟机器人，它们占领了客户支持的席位。     

A review of: “FUZZY SETS,UNCERTAINTY, AND INFORMATION,” by George J. Klir and Tina A. Folger. Prentice Hall,Englewood Cliffs,N.J., 1988, XI+ 355 pp.

Possibility distribution introduced by Zadeh ["Fuzzy sets as a basis for a theory of possibility theory", Fuzzy Sets Syst. 1 (1978) 3-28] in his introductory paper of possibility theory assumes a normal distribution, in the sense that it supposes the existence of at least one element s 0 of the universe of discourse U , for which the distribution ~ is fully compatible with the context of interest: ~ (s 0 )=1. However, when such element does no longer exist, it leads to a subnormal possibility distribution. This situation may arise from incomplete data, inconsistent statements, or contradictory beliefs. To deal with such case, many authors like Yager ["On the relationships of methods of aggregation evidence in expert systems", Cybern. Syst. , 16 (1985) 1-21; "A modification of the certainty measure to handle subnormal distributions", Fuzzy Sets Syst. , 20 (1986) 317-324], Dubois and Prade ["An alternative approach to the handling of subnormal possibility distributions--A critical comment on a proposal of Yager", Fuzzy Sets Syst. , 24 (1987) 123-126] have put forward some proposals in order to keep track of the consistency of the basic axioms attached to possibility and necessity measures. In this paper, the proposals are reviewed in the light of new results regarding some appealing criteria. Particularly, when subnormal distribution and normal distribution are encountered in the same level, intuitively, two approaches are possible: Either the subnormal distributions are risen up to a normal distribution level, or the normal ones are flatted down to agree with the normal ones. In both cases there is a sort of gaining or losing information. We review some of the proposal solutions. The flatting approach is mainly related to fuzzy arithmetic calculus while the rising effect is motivated by Dempster-Shafer theory of evidence and its normalization paradigm. The two approaches will also be investigated with respect to some appealing criteria like preference preservation, distance minimization, entropy, minimum/maximum specificity, and, further, particular interest is focused on information based uncertainty preservation. Later on, the proposals are discussed according to the f -certainty qualification where the greatest value h of the subnormal distribution is understood as a degree of certainty that must be attached to the resulting normal distribution.     

A Review of: “Exploration of the Solar System by Infrared Remote Sensing”. By R. A. HANEL,B. J. CONRATH,D. E. JENNINGS and R. E. SAMUELSON. (Cambridge: Cambridge University Press, 1992.) [Pp. 458.] Price £75.00.

Crop classification is a key issue for agricultural monitoring using remote-sensing techniques. Synthetic aperture radar (SAR) data are attractive for crop classification because of their all-weather, all-day imaging capability. The objective of this study is to investigate the capability of SAR data for crop classification in the North China Plain. Multi-temporal Envisat advanced synthetic aperture radar (ASAR) and TerraSAR data were acquired. A support vector machine (SVM) classifier was selected for the classification using different combinations of these SAR data and texture features. The results indicated that multi-configuration SAR data achieved satisfactory classification accuracy (best overall accuracy of 91.83%) in the North China Plain. ASAR performed slightly better than TerraSAR data acquired in the same time span for crop classification, while the combination of two frequencies of SAR data (C- and X-band) was better than the multi-temporal C-band data. Two temporal ASAR data acquired in late jointing and flowering periods achieved sufficient classification accuracy, and adding data to the early jointing period had little effect on improving classification accuracy. In addition, texture features of SAR data were also useful for improving classification accuracy. SAR data have considerable potential for agricultural monitoring and can become a suitable complementary data source to optical data.     

A Review of: “Bibliography of Geologic Studies Using Imaging Radar.” Compiled by M. LEONARD BRYAN. (JPL Publ. 79-53, 1979.) [Pp. 121.] Available from NASA/JPL,California Institute of Technology,Pasadena, California,U.S.A.

In high mountainous areas, such as the Himalayan Range where snow melt run-off contributes substantially to streamflow, information on snow depth and snow areal extent is vital for the estimation of streamflow and for water resources management. Microwave radiationpenetrates through clouds and snowpacks and is thus considered an important tool for providing water equivalent information on snow fields. The scanning multichannel microwave radiometer (SMMR) on board the NIMBUS-7 satellite acquired passive microwave data for 9 years (1978-1987). These SMMR data are used to test a snow algorithm that is applicable for high elevation areas (>3500m) in the Himalayan Range. The study demonstrates promising results, suggesting the application of SMMR data to derive snow-depth and snow-extent information for the Himalayan region. The generated snow maps can be used for various hydrological applications. The limited availability of field data and its comparison with the SMMR data (which are areal in nature), are major limitations in achieving close correlations between two observations. This is the first application of SMMR data for the determination of snow parameters in the Indian Himalayas. Thus, such an application sets a pace for further research and application of passive microwave data in the most rugged terrains of the world.     

A review of: “Design of Modern Control Systems” Edited by D. J. BELL,P. A. COOK and N. MUNRO. (I.E. 13. Control Engineering Series 20) Peter Peregrinus Ltd, 1982, pp. 330. Price £19·50.

A nonlinear state-space model representing the robot dynamics and containing a disturbance term due to gravitational loading is presented. An adaptive model-following control problem satisfying the matching conditions is formulated using a suitable linear time-invariant reference model. The control input is designed to have two components: a non-adaptive linear component to do the task of model-following and a nonlinear unit-vector component based on hyperstability theory to do the adaptive task. An additional integral feedback term is further added and then the overall asymptotic hyperstability is established. Simulation experiments on the first three joints of a PUMA 560 robot manipulator have indicated the potential of our design approach.     

Review of: “Glaciers-Ocean-Atmosphere Interactions”. Edited by V. M. KOTLYAKOV,A. USHAKOV and A. GLAZOVSKY,Proceedings of the International Symposium,St Petersburg, 24-29 September 1990 (Wallingford,UK: IAHS Press, 1991.) [Pp. 549.] Price US$60.

Data gathered during the NASA sponsored Multisensor Aircraft Campaign Hydrology (MACHYDRO) experiment in central Pennsylvania (U.S.A.) in July, 1990 have been analysed to study the combined use of active and passive microwave sensors for estimating soil moisture from vegetated areas. These data sets were obtained during an eleven-day period with NASA's Airborne Synthetic Aperture Radar (AIRSAR), and Push-Broom Microwave Radiometer (PBMR) over an instrumented watershed, which included agricultural fields with a number of different crop covers. Simultaneous ground truth measurements were also made in order to characterize the state of vegetation and soil moisture under a variety of meteorological conditions. Various multi-sensor techniques are currently under investigation to improve the accuracy of remote sensing estimates of the soil moisture in the presence of vegetation and surface roughness conditions using these data sets. One such algorithm involving combination of active and passive microwave sensors is presented here, and is applied to representative corn fields in the Mahantango watershed that was the focus of study during the MACHYDRO experiment. In this algorithm, a simple emission model is inverted to obtain Fresnel reflectivity in terms of ground and vegetation parameters. Since Fresnel reflectivity depends on soil dielectric constant, soil moisture is determined from reflectivity using dielectric-soil moisture relations. The algorithm requires brightness temperature, vegetation and ground parameters as the input parameters. The former is measured by a passive microwave technique and the later two are estimated by using active microwave techniques. The soil moisture estimates obtained by this combined use of active and passive microwave remote sensing techniques, show an excellent agreement with the in situ soil moisture measurements made during the MACHYDRO experiment.     

S.M.A.R.T的故事

这里是一个互动学习的园地，你既可以提出问题让茶水博士回答，也可以与大家一同分章你所了解的知识。     

亲密接触 A.I.Wars

上次给大家介绍了A.I.Wars,想必大家一定还记忆犹新吧!现在市场上的游戏品种众多,而且模式都是固定的,不能根据玩家自己的想法来玩,这款A.I.Wars游戏就能满足自己设计游戏细节的要求,这样更能锻炼自己的动手能力。有的朋友要问了,我们对编程不熟悉啊,没关系,跟我来吧,我来带领大家一起玩这个游戏!     

清除VBS.Homepage.A病毒

网络不仅仅是我们办公的好帮手,也是个各种病毒的滋生地,刚刚送走了“欢乐时光", 又要遭受VBS.Homepage.A的侵袭。提心吊胆的日子里,江民为我们送来了“解药",只要用 最新版本的KV3000就可以很轻松的查杀这种病毒。江民公司捕获了一种全新的网络蠕虫病毒,其名为VBS.Homepage.A,江民公司提醒广大KV 3000的用户及时升级您的KV3000到最新版本,安装KV3000的实时监测软件,加强防范。新的网络蠕虫程序VBS.Homepage.A,它是VBS脚本语言的形式,必须依靠WINDOWS的WSH来运 行,是利用微软OUTLOOK邮件程序的漏洞来传播的。…     

CMOS Design of Ternary Arithmetic Devices Wu Xunwei Dept.of Electronic Engineering,Hangzhou University,Hangzhou 310028F.P rosser Dept.of Computer Science,Indiana University,U.S.A.

This paper presents CMOS circuit designs of a ternary adder and a ternary multiplier,formulated usingtransmission function theory.Binary carry signals appearing in these designs allow conventional look-aheadcarry techniques to be used.Compared with previous similar designs,the circuits proposed in this paperhave advantages such as low dissipation,low output impedance,and simplicity of construction.