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The construction of the charging station and battery-swap station can ensure the development of the electric vehicles industry. In the paper, the difference of the charging station and battery-swap station is investigated, including the economic cost and benefit of the different mode. In addition, the factors affecting the development of the charging station and battery-swap station is analyzed. In the end, the problems for the construction of charging station and battery-swap station in Chongqing are analyzed.

This paper presents a new mathematic model which is based on wavelet neural network theory algorithm. This model thrives from wavelet analysis theory and is applied in power load prediction. The author analyzes power load in any dimension and collects it effectively with wavelet analysis method. At the end of this paper, the authors analyze the model parameters and discuss various factors deeply.

The Train Control Language (TCL) is a domain-specific language that allows automation of the production of interlocking source code. From a graphical editor a model of a train station is created. This model can then be transformed to other representations, e.g. an interlocking table and functional blocks, keeping the representations internally consistent. Formal methods are mathematical techniques for precisely expressing a system, contributing to the reliability and robustness of the system through analysis. Traditionally, applying formal methods involves a high cost. This paper presents a formalization of TCL, including its behavior expressed in the constraint solving language Alloy. We show how analysis of station models can be performed automatically. Analysis, such as simulation of a station, searching for dangerous train movements and deadlocks, is used to illustrate the approach.

The relationship between the arrival-departure lines quantity and the station capacity is described. Station capacity is the guarantee of the network capacity. A study on the relationship between arrival-departure lines quantity and the station capacity can provide the theoretical guidance and a detailed reference database for constructing the passenger dedicated line network and station yard designing. In order to fully utilize the station facility, based on the research of the Station Operation Sim-system (SOS), with specific throat routing algorithm and optimized scheme of application of arrival-departure lines, the research simulated a saturation state of station operation and tracked detailed information of technological processes of trains during simulation. Then it studied the relationship between the arrival-departure lines quantity and the station capacity by simulating diversified station operation processes which have diverse arrival-departure lines quantity but similar throat layout. Finally, this paper presents the result of the research and analyzes the simulation results to give certain suggestion.

The incredible popularity of home weather stations shows that it’s not just farmers who are interested in the weather. Many people want to be able to track and record weather events within their local environment rather than relying on a state or national weather service that may not have adequate local details.

Orbiting very long baseline interferometry based on radio transmission of a reference signal from an Earth-bound oscillator is considered. This method provides the possibility of forming a connected-element interferometer between the spacecraft and an Earth radio telescope co-located with the reference oscillator. The reference signal from the spacecraft to the Earth is retransmitted and the round-trip time is continuously measured by assuming reciprocity of the path; the time at the spacecraft is always known relative to a clock on the Earth. The author is concerned with the design of such a round-trip reference system and its accuracy limitations. Spacecraft and Earth station models, continuous contact and simple-frequency timing, ambiguity-free timing link design, and the onboard synthesizers are discussed. A design example is presented. >

This paper presents practical results in the field of modern instruments dedicate to monitor the stability of the hydroelectric dams. The general purpose is to provide reliable instruments for the assessment and control of the risk, in order to ensure the conditions for the sustainable development of the hydrotechnical sites areas. This will be done by the means of reducing the vulnerability of the area to natural disasters and technological accidents caused by the malfunctioning of the hydrotechnical site components. In this serie, one device is TP 202 Telependulum, a precise optoelectronic remote readout unit for the wire position of both direct and inverted pendulum. The device is a result of the last years of research in this particular field, a contribution in development and innovation systems, full compatible with the Roumanian surveillance system used by SC Hydroelectrica S.A. (software package UCCHALL) , but also an independent data logger sensor, capable to auto-programable readings, store and transmit data.

A typical hydrogen refueling station was designed based on DOE targets and existing gasoline filling station operations. The purpose of this design was to determine typical heat loads, how these heat loads will be handled, and approximate equipment sizes. For the station model, two DOE targets that had the most impact on the design were vehicle driving range and refueling time. The target that hydrogen fueled vehicles should have the equivalent driving range as present automobiles, requires 5 kg hydrogen storage. Assuming refueling occurs when the tank is 80% empty yields a refueling quantity of 4 kg. The DOE target for 2010 of a refueling time of 3 minutes was used in this design. There is additional time needed for payment of the fuel, and connecting and disconnecting hoses and grounds. It was assumed that this could be accomplished in 5 minutes. Using 8 minutes for each vehicle refueling gives a maximum hourly refueling rate of 7.5 cars per hour per fueling point.

Functioning of an adaptive automated system of operational management of the locomotive park should be based on an accurate operational forecast of the rail direction train operation. For this purpose it is necessary to create a forecast model of the rail direction train operation, the main task of which is the calculation of the readiness moments of trains’ various categories for departure at the technical stations, as well as the calculation of the readiness moments of locomotives and crews for departure with trains. The forecast model of the rail direction train operation includes block forming input information (forming information about the train, locomotive, crew), the trains’ arrival forecasting module (calculation of the forecast time of trains’ arrival), the modules forecasting work of the locomotives (calculation of the forecast time of locomotives’ readiness) and the crews (calculation of the forecast time of locomotive crews’ readiness) and the station functional model (calculation of the forecast time of trains’ readiness for departure) and the locomotive depot model (calculation of the forecast time of locomotives’ and crews’ readiness for departure with trains). The development of the work plan of the locomotives and crews using adaptive model can be considered as an optimization problem solution of binding locomotives and crews to the trains. As an optimality criterion is most advisable to choose the total operational costs associated with downtime of wagons (wagon-hours), locomotives (locomotive-hours) and locomotive crews (crew-hours) at the technical stations while expecting the departure. The optimal variant of the operational work plan of the locomotive park at the railway direction is determined by the minimum of the operational costs associated with unproductive downtime at the technical stations.

In this paper the base station issues for two indoor environments, home and office, are discussed. The two environments differ greatly in their characteristics and, consequently, different solutions are needed. At homes, the key issue is the cost of the base station. To meet the low-cost requirement, a MS based HW architecture for the base station is needed. The usage of only few timeslots instead of eight will cause the air-interface to change. Two proposals for air-interface standard are discussed: Adaptive Frequency Allocation (AFA) and Total Frequency Hopping (TFH) In offices, the key issue is spectral efficiency. The GSM operators will face the challenge of providing high capacity in urban down town areas with only few carriers. Contemporary base station fail in doing it in a cost effective way. New hybrid solution, where the best parts of a single cell and multicell architecture are used, is presented.

In the pumped storage stations, the operating point of reversible pump turbine and the water flow direction in conduit system often change. There is no detailed pumped storage station model in present commercial power system simulation software. The ideal hydro turbine model can only be applied under the generating operating condition, but can't be applied under the pumped operating condition, the conversion of operating condition, large disturbance simulation, and so on. In this paper, a new detailed pumped storage station model is established by the PSS/E user-written model: The reversible pump turbine is represented by the improved SUTER transform characteristics model, which is based on the four-quadrant operating characteristics. And the conduit system is represented by the versatile model. Based on the PSS/E power system models, the generating operating condition, the pumped operating condition, the conversion of operating condition and large disturbance can all be simulated. The application of this model to the test systems is carried out and the results show that the pumped storage station model is valid.

The philosophy of ground station operations at the Rutherford Appleton Laboratory is to provide a low-cost service to a range of science missions. The low cost philosophy is reflected in the automation of much of the operation and the acceptance of some risk by not having staff permanently present during regular operations. The autonomous nature of the operation of the ground station enables us to be a standard part of the worldwide ground system for taking data from the NOAA Advanced Composition Explorer mission at very low cost. This ground system needs to function 24 hours a day. The paper will describe the operational methods and technology used in the RAL ground station in order to achieve the benefits, while minimising the risk of this method of operation. It will also describe the operations that we undertook in support of two small satellite missions, MarocTUBSAT and BADR-B, and how a versatile system, coupled with innovative staff, recovered one lost mission. Finally the paper will describe the future plans for developing the ground station as part of the European Network of Centres concept.

Sump model testing is mainly used to check flow conditions around the intake structure. In present paper, numerical simulation with SST turbulence model for a scaled sump model was carried out with air entrainment and two phases for prediction of locations of vortex generation. The sump model used for the CFD and experimental analysis was scaled down by a ratio of 1:10. The experiment was performed in Korea Maritime and Ocean University (KMOU) and the flow conditions around pump's intake structure were investigated. In this study, uniformity of flow distribution in the pump intake channel was examined to find out the specific causes of vortex occurrence. Furthermore, the effectiveness of an Anti Vortex Device (AVD) to suppress the vortex occurrence in a single intake pump sump model was examined. CFD and experimental analysis carried out with and without AVDs produced very similar results. Without the AVDs, the maximum swirl angle obtained for experimental and CFD analysis were 10.9 and 11.3 degree respectively. Similarly, with AVDs, the maximum swirl angle obtained for experimental and CFD analysis was 2.7 and 0.2 degree respectively. So, with reference to the ANSI/HI 98 standard that permits a maximum swirl angle of 5 degree, the use of AVDs in experimental and CFD analysis produced very desirable results which is well within the limit.

Summary form only given. A holistic systems perspective has been employed to conceptualize different models for such collaboration. A specific model, termed the service station model, with attractive attributes suited to the contexts of many countries and economies, has been put forward for adoption. This model has the major advantages of making service to the community a central tenet. Employment orientation and imparting of skills needed for jobs within the community is accorded the highest priority. Programs and courses are made sensitive to the changing demands of the employing sectors, and when a particular area/speciality is no longer in demand, it automatically gets closed. This market sensitivity is built into the model. >

The Nouragues tropical forest research station was established in 1986 to implement research on the natural mechanisms of forest regeneration. We chose to select a place relatively removed from rivers (navigable water courses) but yet not too far from Cayenne (for obvious financial reasons) and close to a pre-existent light research camp established by the National Museum of Natural History on the Parare rapids of the Arataye river. Both the fauna and flora of this area had been under study since 1978, and this provided a valuable scientific data base on which to build further research.

Several examples of dynamic objects 3D images and high-speed process observations and measurement, are presented. The gun-powder burning process. The real droplet distribution in diesel fuel sprayers. The pressure distribution in T-joint of automobile fuel discharge system. The thin wires explosions--the model of real bursting processes. The pulsed discharge lamps, using for solid-state lasers pumping. The gas-liquid flows in tubes. Measuring the velocity distribution in waterfall at hydra-electric station model. All these and alike measurements at Holography Lab of VNIIOFI, (Moscow, Russia) for different scientific and industrial establishments, were provided.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

As a complement to the previous chapters, this chapter on the International Space Station (ISS) will describe the special characteristics relevant to the mission, planned laboratory facilities, and user support as well as important technical and programmatic aspects of the station’s operation.

Planners for the Deep Space Network at JPL require long-term forecasts of ground station view periods. The standard approach requires orbit integration up to 20 years. The geometry of the satellite groundtrack and station mask suggests the use of ergodic theory. An invariant measure was found which enabled the application of the Ergodic Theorem to this problem. The total view period for a circular orbit is given by a definite integral over the sphere. This paper presents the derivation of the invariant measure.

This article focuses on the use of airships to provide Wi-Fi broadcasting. Park an antenna high in the stratosphere and then relay signals to and from devices below. Such an airborne transceiver could blanket urban areas with wireless coverage more cheaply than satellite-based alternatives while avoiding the need to build forests of mast-mounted base stations on the ground. This spring engineers at Sanswire Networks, an Atlanta-based Wi-Fi provider, plan to test a prototype of a high-tech airship that they claim could supply mobile communications service to major metropolitan areas for as long as 18 months at a stretch. Beyond standard financial and political difficulties, these projects face formidable technical difficulties. INSET: CONTINUOUS COVERAGE.

Verification of analytical models through correlation with ground test results of a complex space truss structure is demonstrated. A multi-component, dynamically scaled space station model configuration is the focus structure for this work. Previously established test/analysis correlation procedures are used to develop improved component analytical models. Integrated system analytical models, consisting of updated component analytical models, are compared with modal test results to establish the accuracy of system-level dynamic predictions. Design sensitivity model updating methods are shown to be effective for providing improved component analytical models. Also, the effects of component model accuracy and interface modeling fidelity on the accuracy of integrated model predictions is examined.

Concerns over global warming and high oil prices are expected to lead to a continuous increase in electricity generated by distributed renewable energy sources and small-scale embedded generators (SSEGs). This increase in SSEG will pose numerous technical challenges for distribution network operators. The small-scale energy zone (SSEZ) concept seeks to overcome these challenges using appropriate coordinated control. An SSEZ is defined as a section of low voltage network with a high penetration of SSEGs, controllable loads and energy storage units. This paper puts forward the concept of the virtual power station (VPS), consisting of a number of aggregated SSEZs, which has the potential to offer significant improvements in the commercial value and environmental impact of the installed SSEGs by enabling provision of ancillary services. In order to evaluate the effectiveness of this concept, a dynamic power system model of a VPS has been developed.

The object of study in this paper is a Brownian model of a multiclass service station. Such Brownian models arise as heavy traffic limits of conventional queueing models in which several different types or classes of customers are processed through a common service facility. Assuming that the Brownian service station is initialized with its stationary distribution, four different model characteristics are shown to be equivalent, and the station is said to be quasireversible if these equivalent conditions pertain. Three of the four conditions characterize the vector departure process from the Brownian service station, and our definition of quasireversibility parallels that proposed by F. P. Kelly for conventional queueing models. The last of our four conditions is expressed directly in terms of primitive model parameters, so one may easily determine from basic data whether or not a Brownian station model is quasireversible. Rather than characterizing the complete vector of departure processes from a Brownian service station, we prove a more general theorem expressed in terms of arbitrary linear combinations of the departure processes; this yields a generalized notion of quasireversibility that will play an important role in future work. To be more specific, in a future paper on multiclass Brownian network models, it will be shown that there is an intimate relationship between product form stationary distributions and the generalized notion of quasireversibility developed here.

Archived hourly output from the National Meteorological Center (NMC) prediction models has provided the basis for advanced graphic diagnostic and forecast tools. The high-frequency data are available on a regional selected station network. Each point in the network consists of the basic state variables at each sigma layer and a variety of surface quantities. Five graphics products have been developed at NMC to display the hourly forecast data. They are thermo-dynamic diagrams, standard format meteograms, extended format meteograms, station model plots, and contoured analyses. Graphics workstation animation capabilities enhance the products’ value. Dissemination of a portion of the raw data by the Automation of Field Operations and Services (AFOS) is underway.

The major functions, inputs, and outputs of the seven computer models developed during the Automated Guideway Transit (AGT) System Operations Studies (SOS) project are described. The models were designed to provide tools to enable the transportation community to analyze the operation of AGT systems in the complete spectrum of deployments. Three analytic models are described: the feeder system model, which determines the cost and service characteristics of the non-AGT components of the door-to-door trip; the system cost model, which calculates annual and life cycle costs and environmental impacts; and the system availability model, which calculates the impact of failures and recovery times on passenger and vehicle delays in the network. Four simulation models are described: the discrete event simulation model, which models individual trips and vehicles on AGT networks for a wide range of management algorithms, service policies, and network configurations; the system planning model, which models vehicle and passenger flows on AGT networks; the detailed station model, which models individual vehicle and passenger movement in a station; and the detailed operational control model, which is a time step simulation that models individual or strings of vehicles on links, merges, or intersections.

The paper starts out by discussing factors which influence the Indian monsoon rainfall—including Northern Hemispheric temperature changes, long-period soli–lunar tides, and the tidelike phenomena associated with the wobble of the Earth relative to its spin-axis. When the effects of these factors on precipitation are quantified and integrated into a thermodynamical–statistical model, long-range climatic forecasts can be made that are better than chance or than predicting ‘normal’ up to two or more years in advance.Climatic changes have had profound effects on the peoples of India through the controlling influence of the monsoon on Indian agriculture. We now have a technological tool, never before available, that might lessen the impact of variations of the monsoon by forecasting these variations one to two years in advance. The two-years-in-advance 1982 monsoon rainfall forecast for June and July, using the same station models that produced the excellent 1981 forecast, indicates that there is a two-to-one chance that the 1982 Indian monsoon rainfall will be less, in general, in June and July, than it was in 1981. The question which we wish to ask the reader is: How can this new technology be used? For example, how can this type of information be used for planning and policy-making in order to ensure less uncertainty about food supplies in the future than in the past?This region cannot depend upon the monsoon to bring plentiful rain every year, and, therefore, it is essential that we should continue to improve our forecasting capability and that others learn to make optimum use of these forecasts.

The Fiering model for the simultaneous generation of synthetic flows at a key station and one statellite station is reconsidered. After pointing out some inadequacies in Fiering's analysis, the model is reformulated. It is then shown how its parameters may be chosen so as to preserve the historical monthly (say) means and variances at each station, and also the first-serial correlation at each station and the simultaneous cross-correlation. The complete correlation structure of the model is obtained. It is further shown how to preserve the historical skewness coefficients of each flow. Finally, a possible extension involving two satellite stations is briefly mentioned.

A stochastic model has been developed for a CVS (Computer-controlled Vehicle System) station with multiple parallel berths. In this model to study the effects of the number of berths on the behavior of a station, the following simplification is made in contrast to the conventional single-berth station models. That is, loading and unloading times for each berth are assumed to follow the same exponential distribution regardless of the vehicle type, and the vehicle departure condition does not depend on the vehicle either. This type of model is formulated as a Markov renewal process and analyzed. As a result we have clarified the fundamental relationships between the number of berths and measures for evaluating a station such as the expected interval time of entrances, the departure rate, the entrance factor and the utilization factor of berths. Also, by examining the asymptotic characteristics of the expected interval time of entrances we have found the fundamental differences between a single berth station and a multiberth station, we have shown trade-offs between the entrance factor and the departure rate and we have investigated the implications of increasing the number of berths. On the other hand, by simulations with a normal loading and unloading time distribution, we examined the effectiveness of the results of this paper for which an exponential distribution was assumed for the loading and unloading times.