摘要：A new approach is proposed which can satisfy the range ambiguity requirement while keep the antenna width not to be enlarged and get the high quality image also. Here the chirp slope of the transmitted linear frequency modulated pulses is reversed alternately. Therefore, during the range compression significant portion of the ambiguous return which is due to the mismatching with the signal reference function is suppressed. The suggested method provides significant improvement in range ambiguity ratio and can be utilized in attaining wider swath.

摘要：Based on the α-β bifurcation curves and the special characteristics of chaotic spectrum of chua’s circuit, this paper presents here a method for designing a Chua’s circuit which approximately satisfy specified spectrum distribution range.

摘要：With the rapid development of urban economy, distribution network construction of city is lagging behind the increment of load, and low-voltage problem has become the main complaints of the power users. Based on Python [1] scripting language, this paper develops a piece of software which can provide a friendly human-machine experience for the user, calculate the voltage of the power distribution area and propose corresponding control measures, then the paper takes the actual power distribution area to verify its effectiveness.

摘要：This study was done for one of the Nigerian National Petroleum Corporation （refiner） depot supplied by a multi-product （gasoline, diesel and kerosene） pipeline. distribution/loading facility designed for a total of six arms： two each for gasoline, kerosene and diesel （or 33.33% for each product） whereas gasoline storage capacity is 55%, diesel, 33%, kerosene 11%, and slops, 1% of the total depot capacity. The design supply to distribution chain capacity ratio showed a mismatch, which in actual operation becomes 2：1. The above design created ullage problem at sustained supplies, gross under utilization of supply chain infrastructures and poor operational performance. After a technical evaluation, a section of the depot storage to loading pipeline network was re-designed and modified to enable products supply capacity to match loading and minimize storage. Hence, the gasoline loading became 66.67%, kerosene and diesel, each of 16.67%, increasing the actual supply to distribution chain capacity ratio from 2：1 to 2：2 （and when required, can be maximized to 2：3） thereby correcting the apparent mismatch between the supply and distribution chain capacities. The modification has enabled the refiner to increase depot and upstream supply chain utilization

摘要：Water distribution Systems (WDSs) design and operation are usually done on a case-by-case basis. Numerous models have been proposed in the literature to solve specific problems in this field. The implementation of these models to any real-world WDS optimization problem is left to the discretion of designers who lack the necessary tools that will guide them in the decision-making process for a given WDS design project. Practitioners are not always very familiar with optimization applied to water network design. This results in a quasi-exclusive use of engineering judgment when dealing with this issue. In order to support a decision process in this field, the present article suggests a step-by-step approach to solve the multi-objective design problem by using both engineering and optimization. A genetic algorithm is proposed as the optimization tool and the targeted objectives are: 1) to minimize the total cost (capital and operation), 2) to minimize the residence time of the water within the system and 3) to maximize a network reliability metric. The results of the case study show that preliminary analysis can significantly reduce decision variables and computational burden. Therefore, the approach will help network design practitioners to reduce optimization problems to a more manageable size.

摘要：A 28 V-half-regulated power bus topology and an integrated PCDU (Power Conditioning and distribution Unit) were adopted to meet the energy demand for the Chang'e 4 relay *** paper first introduces the mission features and composition of the PSDS (Power Supply and distribution System) for the Chang'e 4 relay *** to this satellite's unusual orbit,operational mode and project restrictions,special analysis and design was conducted on the PSDS from the perspective of weight-reduction,power management,and reliability and so *** low temperature storage of SA (Solar Array) was considered and how the antenna affects the SA was analyzed.A new kind of high-specific-energy 45 Ah (Ampere-hour) battery cell was used for the first *** make sure that the satellite would successfully pass the long shadow zones,a 100% DOD (Depth of Discharge) experiment was carried out on the *** the sunlight is almost always available and there are very few times for the battery to charge or discharge,battery care to extend its lifetime is also *** is a device that integrates power conditioning and power distribution in one *** PCDU on Chang'e 4 relay satellite can output more power with less weight because of the adoption of a 28 V-half-regulated power bus topology which was also used for the first time and used lighter material for its mechanical *** under low temperature on PCDU was conducted as well and a hot backup equalizing charge technique which is beneficial to keep performance of the battery is *** power distribution module,which is a module of PCDU,enhances the power utilization security by utilizing a static impedance measurement and build-in-test to avoid possible short *** for EED (Electrical Explosive Device) module,a protection plug was specially designed and three switches with different functions were connected in series to prevent the EED from exploding by *** addition,the allowable

摘要：Compound parabolic concentrator(CPC) is a representative among solar concentrators, one of whose disadvantage is that the concentration ratio limits the half acceptance angle. Based on this, researchers put forward a novel structure, named the lens-walled CPC. This paper reviews the design and development of lens-walled CPC. The structure of the symmetric and asymmetric lens-walled CPC and the improved ones are presented, and their indoor and outdoor performances are also illustrated. The lens-walled CPC has a larger half acceptance angle and a more uniform flux distribution that is suitable for PV application. Furthermore, the life-cycle assessment for building integrated with PV is performed and it shows that the energy payback time of such integrated system has a significant advantage. In addition, future research areas are also indicated that may provide more functions and more stable performance. The design methods and developmental directions given in this study would provide many references in solar optical research and solar concentrator optimization.

摘要：We studied the reliability of machine components with parameters that follow an arbitrary statistical distribution using the principle of maximum entropy(PME).We used PME to select the statistical distribution that best fits the available *** also established a probability density function(PDF)and a failure probability model for the parameters of mechanical components using the concept of entropy and the *** obtained the first four moments of the state function for reliability analysis and ***,we attained an estimate of the PDF with the fewest human bias factors using the *** function was used to calculate the reliability of the machine components,including a connecting rod,a vehicle half-shaft,a front axle,a rear axle housing,and a leaf spring,which have parameters that typically follow a non-normal *** were conducted for *** study provides a design methodology for the reliability of mechanical components for practical engineering projects.

摘要：Based on the extreme value theory, self-affinity, and scale invariance, we studied the temporal and spatial relationship and the variation of water level and established a model of Gumbel-Pareto distribution for designed flood calculation. The model includes the previous extreme value models, the over-threshold data, and the fractal features shared by previous extreme value models. The model was simplified into a logarithmic normal distribution and a Pareto distribution for specific parameter values, and was used to calculate the designed flood values for the Shanghai Wusong Station in 100- and 1 000-year return periods. The calculated results show that the value of the designed flood height calculated in the Gumbel-Pareto distribution is between those in the Gumbel and Pearson-Ⅲ distributions. The designed flood values in the 100- and 1 000-year return periods of the model were 0.03% and 0.11% lower, respectively, than the Gumbel distribution and 0.06% and 1.54% higher, respectively, than the Pearson-Ⅲ distribution. Compared to the traditional model based solely on extreme probability, the Gumbel-Pareto distribution model could better describe the probabilistic characteristics of extreme marine elements and better use the data.

摘要：In this paper, associations between two sets of random variables based on the projection pursuit (PP) method are studied. The asymptotic normal distributions of estimators of the PP based canonical correlations and weighting vectors are derived.