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The application of power electronics can introduce flexibility into power systems, but it can also cause harmonic problems. As a typical application of power electronics, high-voltage direct current (HVDC) transmission exhibits very prominent harmonic problems. In recent years, many HVDC protection maloperation events caused by harmonic problems have occurred in the field. The phenomena of harmonic transfer and amplification in HVDC transmission have an undeniable impact on the overall operation of a power system. Previous studies of these phenomena have relied mainly on detailed electromagnetic transient simulations. However, these simulations normally suffer from a large computational burden and low efficiency due to the complexity of the models and the small simulation time steps used. Therefore, an efficient analysis model of harmonics for various HVDC operating modes is presented in this paper. This model is based on port theory; every part of the HVDC transmission system is represented by an equivalent two-port component to construct a unified equivalent circuit. The proposed model is simple to calculate, and only the connections of the two-port components need to be changed to model different operation modes. The proposed two-port model is applied for the harmonic analysis of an HVDC transmission system, and the validity and accuracy of the model are confirmed by detailed electromagnetic simulations. Moreover, the model can be easily applied to HVDC systems for harmonic transfer and amplification, and the effects of the HVDC transmission power and smoothing reactor on harmonic transfer and amplification are analyzed.

A utility operation massage robot structure is proposed in this paper, which has the characteristics of flexibility and versatility compared with other existing massage robots. Three humanoid massage types are achieved by the proposed robot structure, which include physical beating mode, physical pressing mode and physical rubbing mode. Its performance is analyzed by discussing its working space and movement status. The validation of the proposed massage robot has been performed by the results of the simulation experiment.

With a significant increase of load type and distributed generator permeability in multiple community integrated energy systems (CIESs), a hybrid distribution system (HDS) including AC/DC power network and heat network is required to satisfy multi-energy demands. This paper presents a detailed model for CIES and HDS to realize cascade utilization of multi-energy. To overcome the profit conflicts among HDS and multiple CIESs, a coordinated operation model based on hierarchical decentralized scheduling is proposed. Furthermore, the alternating direction method of multipliers (ADMM) algorithm is used to solve this coordinated model. Finally, the proposed model and method have been verified on a test HDS, which consists of an IEEE 33-bus AC power system coupling with a 4-bus DC power system and a 6-node heat system, and multiple CIESs which locate in Jiangsu Province, China.

Vehicle-to-grid (V2G) of electric vehicles (EVs) can help an EV charging station (EVCS) participate in demand response (DR) to save costs. The EVCS owned by a logistics center is responsible to satisfy the charging demands of logistics EVs and private EVs owned by the staffs. The charging behaviors of the two types of EVs are different and have their own regular pattern, which can be considered to guide operation strategy decision-making for the EVCS. Under time-of-use (TOU) pricing, an optimal day-ahead operation model of the EVCS in the logistics center is proposed in this paper, aiming at minimizing the operation electricity costs. By joining in V2G service, two types of EVs contribute to the cost reduction of the EVCS, with charging behaviors of different types of EVs on weekdays and holidays considered. Case studies are conducted to validate the proposed method and the results show that the proposed method can minimize the costs of the EVCS with charging demands of EVs satisfied.

Increasing numbers of blockchain applications will be faced with groundbreaking technologies. In this context, two research questions arise. First, deciding which use cases are profitable for business transformation and, second, ascertaining how the blockchain technology can be mapped and operated analogous to an IT Service Manangement approach. We believe that the introduction and application of Blockchain concepts must be considered in the context of the overall IT ecosystem of an organization. Therefore, we will provide a comprehensive decision and operating model, called BCDM, for the implementation of blockchains that will allow us to answer these two questions.

On the basis of considering the flood control safety of the reservoir and protection area, a multi-objective flood optimal operation model of reservoir is established, and a combined algorithm called SA-FOA combined with Simulated Annealing Algorithm(SA) and Fruit Fly Optimization Algorithm(FOA) is used to solve the model. The SA-FOA overcomes the shortcomings of fast convergence speed and easy to fall into local optimal solution of FOA. Taking the flood hydrograph 19630717 and 19640912 of Tianzhuang Reservoir as an example, discharges calculated by SA-FOA are compared with measured values. The results show that the maximum discharges and maximum water levels of the two flood hydrographs calculated by SA-FOA are smaller than those of the measured values, and the discharges calculated by SA-FOA are more uniform, which verifies the safety and feasibility of this algorithm.

With penetration levels of photovoltaic (PV) generation substantially increasing, electric power systems need more flexible resources that can provide ancillary services to mitigate the variability and uncertainty of the PV. On one hand, the increase in PV generation necessitates more flexible resources; on the other hand, because of its low operation cost, PV generation has been replacing conventional generation, which is currently the main flexible resource. Consequently, there is a trend to require renewable generation, including PV, to provide flexible ancillary services. This paper proposes a multi-timescale grid operation model considering the various control strategies of PV providing different ancillary services. Numerical case studies demonstrate that with PV providing both regulation reserve and primary frequency reserve, the system operating costs and PV curtailment will be reduced significantly. Results show that not only the system reliability can be improved but also PV profitability with PV providing more ancillary services.

The joint scheduling of multi energy micro energy network group can effectively absorb the residual heat of electricity in each sub micro network through the characteristics of energy substitutability and multi-agent interaction. However, the complex relationship of multi energy interaction brings difficulties to joint scheduling. In order to minimize the operating cost of the system, this paper establishes a day ahead optimal scheduling model of multi energy micro grid group of cooling, heating and power considering the consumption of clean energy. Through thejoint scheduling of micro grid group, it can promote the consumption of residual heat in the sub micro grid. Finally, in an example, by optimizing the operation of a multi-functional microgrid group, the mechanism of joint scheduling of multifunctional microgrid group is analyzed, and the effectiveness of the optimization operation model proposed in this paper is verified.

Information security (IS) is essential and important in different application fields. Medical databases (MD) and healthcare applications (HA) are not an exception; information security plays a prominent role in the protection of patient data by encryption. Securing the privacy of patients is an imperative challenge. MD and HA adopted encryption as a technique to secure the data, especially for patients with disabilities. Previous research works in the field of data security reported the application of a new select operation model in the encryption-based on multilevel security approach to multilevel database; these models enhanced the security level (SL) of databases due to the encryption based on multilevel security (MLS) but their performance is not as efficient in medical database management systems (DBMS) due to the huge size of records and several decryption operations needed. The original select model becomes very inefficient when the number of records (size of data) becomes large. In this paper, we modify the select operation model in multilevel database to enhance its performance, when the encrypted data is retrieved. Nevertheless, the obtained results in this paper show that the proposed modifications give better performance as compared with results obtained from the original model.

With the implementation of the concept of "Energy Internet", the integrated energy system as the physical carrier of the Energy Internet has been further developed. A regional integrated energy system optimal operation model considering flexible heating load is proposed. Firstly, combined with the basic principles and operation characteristics of typical equipment in the integrated energy system, the main equipment model of the integrated energy system is formed. Based on the user's work and rest rules, a flexible heating load model considering the user's flexible comfort constraints is constructed to increase the system's operation flexibility. Then, a mathematical model for the optimal operation of the regional integrated energy system based on the bus-based structure is constructed. Finally, three different heat and power dispatch methods are defined to analyze the benefits of the combined heat and power dispatch in an integrated energy system. The simulation results show that the optimal operation model of regional integrated energy system considering flexible heating load can improve energy efficiency and reduce the system operation cost.

On the basis of sorting out Lawson’s entry into Shanghai, this article analyzes the difficulties encountered by Lawson Fund in the development of Shanghai, including: capital, the restrictions of China’s relevant policies, Lawson’s business model, especially the logistics system, which is difficult to copy the Japanese model. To manage predicament, Lawson adopted a series of countermeasures. In the countermeasures to break through the predicament, the operation mode of the store and the localization strategy of the logistics system play an important role. The in-depth analysis of the store operation model and logistics system has certain enlightenment for other Japanese enterprises to enter the Chinese market.

The thermal inertia of district heating system (DHS) has been considered in the combined heat and power (CHP) system operation to reduce wind curtailments. While DHS usually operates at the quality-regulation mode, under which the potential of public buildings to regulate heat demand is not fully exploited. In this paper, according to the different heat demand characteristics of public buildings (PB) and residential buildings (RB), a CHP system operation model adopting a centralized control with flow varied by steps in DHS operation regulation is proposed. Case studies show that the proposed model has better performance in economic benefits and wind power integration.

Nowadays, large-scale power outages induced by ever-growing natural disasters are increasing at a galloping rate. In this regard, this paper aims at improving the resilience of power distribution systems in facing high impact low probability (HILP) events in the planning phase of the system. To this end, optimal switch placement along with the optimal distribution line hardening strategies is proposed to mitigate the repercussions of the natural calamities. So, decreasing the failure probability of the distribution lines alongside the optimal placement of remote-controlled switches (RCSs) to increase the maneuvering capability of the system, the system operator would be able to strengthen the system and cope with disastrous events. To do so, in this paper, a proactive strategy is used to simulate the operation of the system in confronting the HILP events. The proposed model implemented on a real 47-bus power distribution system and the efficacy of the model is approved by the simulation results in enhancing the resilience level of the system.

Wind energy is a renewable and energy-rich clean energy source, which is of great significance for energy conservation and emission reduction. However, the uncertainty of wind power makes the wind aggravation. This paper focuses on the principle of cooperative operation mechanism of regenerative electric heating and wind power generation and constructs a cooperative operation model considering relevant constraints. The economics of the model are evaluated by establishing an economic evaluation system. Finally, case studies show that the coordinated operation of wind energy and regenerative electric heating improves the wind power's ability to absorb and the system's peaking ability, effectively alleviating the wind abandonment phenomenon. At the same time, it has improved economics and improved the environment. Contributed to China's resource conservation and environmental protection.

Nowadays, the train-set operation optimization problem has become an important part of intercity railway traffic organization, which is beneficial to reduce the operating cost and improve the efficiency of operation. Referring to the relevant studies, analyze the influence of the operation modes of intercity railway in the case of a known train diagram, and conclude the characteristics of train-sets' uncertain railroad region and empty train dispatching. Then based on the train-set operation network and maintenance conditions, establish the multi-objective optimal model, and combine the tabu search algorithm with the ant search algorithm to solve this problem. In the case, compare the results and calculation time calculated by Lingo with these calculated by the algorithm, the calculation time by the designed algorithm is shorter, and the efficiency of programming is faster, so the feasibility of the model and algorithm was verified. Finally, by comparing some indexes of models with different objectives and constraints, the practical significance of the proposed train-set operation model for intercity railways is verified.

Parallel operation of power transformers is a common phenomenon in power networks and plays a key role in the development of active distribution network (ADN). In this paper, a parallel operation model of a solid-state transformer (SST) and an on-load tap changer (OLTC) is proposed, which can not only improve the power supply reliability of the grid, but also compensate for reactive power and maximize the use of clean energy. On this basis, the reactive power optimization (RPO) model of an ADN under the parallel condition of a SST and an OLTC is constructed. Firstly, considering the SST's own loss, a SST steady-state model is established. Secondly, to eliminate the circulation current in the parallel system, the master-slave control strategy is adopted, and the parallel model is established accordingly. In addition, a modified whale optimization algorithm (MWOA) is proposed for system RPO. Finally, an IEEE 33-bus system is used for the verification of the proposed model.

Along with the development of XML database technology, the research on XML query optimization is increasing, but it is still the weak link of XML database. In this paper, we find out the atomic operation in the traditional query estimation model, and use the method based on statistical learning to find out the operating costs and the functional relationship between these factors. Finally, experiments show that the operation model can effectively improve the query optimization effect.

With the increasing proportion of natural gas energy, the operation scheduling of independent system cannot meet the requirements. This paper proposes an operation model of integrated energy system with second-order cone programming to linearize the non-convex and condition constraints. Not only CHP units, gas fired units, electric heating and gas heating equipment, but the constraints of power flow and gas pipes have been considered in the integrated energy system. Finally, with the case study of 33-node electric system and 19-node gas system, to minimize the operation cost in the optimization, the economical benefit of the model has been proved with Gurobi solver based on Matlab.

Considering the time-space relationship between energy storage and flexible load together with the influence of network power flow, an optimal operation model of active distribution network is established, with the but of maximizing renewable energy utilization, minimizing network loss and maximizing user satisfaction. At the same time, the coordination among the units of active distribution network is quantified by setting the scheduling priorities of controllable distributed generation units, energy storage systems and flexible loads. Finally, an example is analyzed.

In recent years, with the development and application of distributed generation, multi-microgrid structure has gradually become a future development form. However, new challenges have been brought to optimal operation due to its structural dispersion, complex composition, and information barrier. This paper proposes a distributed optimal operation model and solution method based on alternating direction method of multipliers (ADMM) algorithm. The original problem is decoupled into several independent sub-problems including distribution network and microgrids. Based on the second-order cone relaxed power flow model and the chance-constrained method, the model is optimized to realize the optimal operation of a distribution network with multi-microgrid. Finally, a case study is presented based on the modified IEEE33 node system, and the result illustrates the feasibility of the ADMM algorithm and it is applicable to optimize the operation of distribution networks with multi-microgrid.

How to make operation strategy for regional multi-energy system with less energy loss and small cost is worth studying. Optimal operation model of regional multi-energy system is built based on heating water network model, considering heating loss of hot water pipes caused by temperature drop and power consumption of circulating water pump caused by water flow. The corresponding algorithm is introduced to achieve the solution of the model built in this paper. Finally, a supposed multi-energy system is used to conduct a simulation, and the results show that the proposed optimization model of making operation strategy for regional multi-energy system can further reduce energy loss and operation cost.

Capacitor charger resonant topology has been widely used in high-power and high-voltage filed due to the high efficiency and low switching loss. However, the steady-state and dynamic model is not clearly proposed in the past few literatures. This paper shows the derivation process for the topology and presents the operation model under PFM control. The PFM control model is presented and analytical solution is obtained. Experiment results are proposed to verify the theoretical conclusions.

In this paper, we present an optimal operation model for an active distribution utility with inflexible and flexible loads. The proposed model addresses how the flexible loads should be operated to minimize the utility operation cost as well as maintaining the distribution network safe. Moreover, we analyze how the flexible loads can provide the reserve service for the electricity market with highly renewable resources penetration. Assuming T time intervals, we determine the optimal energy and reserve bids to the electricity market that minimize energy procurement cost of the utility and fully comply with the operational standards of the distribution network. From a set of numerical experiments on the 33-bus system, we present the advantages of our proposed model.

This paper presents a driver turning operation model based on the hybrid system representation. First, we collected the driving profile of the turning operation by using a driving simulator (DS) at a city intersection. We identified the driver turning operation model from the obtained information and conducted experiments to verify the validity of the model. As a result, we verified the effectiveness of the proposed method by comparing the driving behavior of the human and the identified model.

With the increasing penetration of renewable energy sources (RES) and strong coupling between electric power systems and other forms of energy, there are vast opportunities and challenges for every practitioner in energy field, especially so many stochastic characteristics to suppress, such as wind, photovoltaic and load demand. This manuscript establishes an integrated optimal operation model of energy internet considering the multi-time-scale stochastic characteristics of RES. Finally, the particle swarm optimization (PSO) algorithm is applied to the optimization of the proposed model and the simulation results show that the proposed model is correct and effective.

This paper presents studies on improving the robustness of shipboard dc hybrid power systems. The shipboard power system can be regarded as an islanded microgrid. The objective, in particular, is to reduce the load curtailment when generator failures take place in the islanded microgrid. By applying the basic unit commitment (UC) operation model, the loads can be fully supplied during normal condition. However, a portion of the loads has to be shed if any generator fails. Two approaches are proposed to mitigate the loss of load during and after fault. They are developed by modifying the UC models. These approaches are evaluated for reducing load curtailment under loss of generation. Selected case studies indicate encouraging results that the loss of load can be reduced during and after generator failure. For carrying out the case studies, the optimization model is built on General Algebraic Modeling System (GAMS) platform.

In this study, we aim to evaluate a driver skill based on the driver behavior model generated by the operation and environment data under driving vehicle. When skill of driver is reduced, the operator behavior is delayed, it takes along time of operation, and execution timing of operation is no reproducibility. These mean that reducing skill of driver affects time information of the driver operation. Therefore, we study on the model structure incorporated time information expresses the execution timing of driver's operation to evaluate driver's skill. In particular, we propose a new model structure incorporated timing probabilistic distribution expresses the time until the execution of next operation. Moreover, we propose a modeling method of operator behavior according to proposed model structure. It is considered that the reaction time from the decision to execution of operation and ambiguity of the decision can be read from the timing probabilistic distribution. In this paper, the above usefulness is examined through some experimental results. Moreover, the applicability of the driving skill evaluation based on the proposed operation model is examined.

This paper explores from a techno-economic perspective the value of increasing distribution network capacity via Demand Side Response (DSR) services provided by smart multi-energy systems enabled by an intelligent information platform (i.e., the District Information Modelling and Management for Energy Reduction (DIMMER) platform under development in the homonymous European project). More specifically, the potential of smart multi-energy systems comprising gas boilers, Electric Heat Pumps (EHP) Combined Heat and Power (CHP) and a smart information platform to provide distribution network capacity is explored. For this purpose, a multi-energy district operation optimization approach coupled with a distribution network planning framework is proposed. The district operation model identifies the behavior of end-users who may aim at minimizing their energy costs and/or trade capacity with DNOs. The network planning framework calculates the value for DNOs from additional network capacity provided by customers. The methodology is illustrated via a real UK multi-energy district at the University of Manchester and the relevant electricity, heat and gas networks. The results highlight that the flexibility inherent in multi-energy systems can provide significant economic benefits for both end-users and DNOs.

In order to efficiently and robustly land more aircraft on two parallel runways, search the conflict-free and less-delay reroute for arrival aircraft, we plan to control arrival aircraft with a novel trajectory operation model named Multi-layer Point Merge System (ML-PM). In this paper, firstly the notional example of ML-PM system is introduced, the characteristics of its horizontal and vertical profiles are described. Secondly, according to the availabilities on two parallel runways, the positions of aircraft on sequencing legs, a trajectory reroute model is built. After that, the geometric relations for conflict detection in merging zones are analyzed in details. Furthermore, two tests with runway re-assignment on and off are compared to study the performances of proposed ML-PM system, the numerical results have shown that: 1) both tests could generate conflict-free trajectories, 2) average delay, average landing interval, and makes-pan could be reduced by runway re-assignment. The relative improvement for average delay is 36.36%, for make-span and average landing interval is 1.35% and 1.36% respectively. However, the average flight time, flight distance, fuel consumption and co(2) emission will increase due to runway re-assignment, the relative increases are 13.49%, 1.11%, 13.49% and 13.49%, respectively. After that, a detailed study about the runway assignment is done, the changes of different indicators are analyzed. Finally, the conclusion is made, ML-PM system shows a very positive ability to dynamically control arrival flows to land on parallel runways. Refereed/Peer-reviewed

In this paper, a mixed-integer linear programing (MIL?) model for the traffic behavior of plug-in electric vehicles (PEVs) in a multi energy system (MES) is proposed. It is assumed that two micro-MESs are covering two traffic zones with different consumption patterns. The difference between these two micro-MESs is not only the different multi energy demand (MED) they provide, but also different PEV traffic pattern that travel in these two micro-MESs. The PEVs traffic pattern and their behavior in using parking lot (PL) or charging station (CS) as their charging places is integrated in the MES operation model. The results demonstrate an improved strategy of the MES operator in using its components, such as combined heat and power (CHP) unit and auxiliary boiler (AB), in response to extra added load of the PEVs. The stochastic behavior of the PEVs is implemented in the model through various scenarios of arrival and departure.

The ability of the grid-friendly microgrid responding the system operation demand is analyzed by exploiting potentialities of grid operation from the traditional load side. The volatility of DGs output is balanced by including controlling EVs the charging and discharging. The output of microgrid is scalable through coordinating all kinds of DGs based on which a microgrid economic operation model is built. The simulation result shows the microgrid can absorb internal intermittent power and achieve system dispatching well by coordinating kinds of powers. Its dispatching potentiality is sizable.

This paper proposes a novel design method of a driver assist system to improve driving safety. For a constant vehicle velocity, an assist system model and a steering operation model are constructed iteratively via Hx loop shaping since both models interact with each other. Then the models designed at different velocities are scheduled since driver's operation characteristics vary according to the vehicle velocity. It was shown that the proposed models performed excellently in lane change simulations where the vehicle velocity varied.

Operation of distributed energy resources is taking importance nowadays. This paper proposes an optimal planning and operation model of distributed energy resources in a district taking into account the mobility of consumers using conventional fuel vehicles (FV) or electric vehicles (EV). The stochastic model considers the uncertainty of the type of vehicle, availability and distance traveled, and then it manages the available resources to obtain the maximum benefit from the grid. Results show that the EVs assist to achieve greater benefits of the distributed resources. Moreover, the costs per driven km are mainly independent of the type of vehicle considered.

This study aims to establish equations for energy consumptions of Taiwan Railways Administration (TRA) trains in operation considering the variations of slope to determine the traction energy cost (TEC). Where railway transportation has been one of the important means of transport for mankind, since TRA became electrified the parameters for train operations have been able to be accurately recorded. The equations for overall energy consumption and resistance parameters are completed for the overall energy consumption of TRA trains and resistance to them to simulate the operation of the whole train model. The inputs of different conditions of trains and track sections are then analyzed for energy use, as the energy use by train travel is obvious. That by the behavior of energy use, can be divided in three conditions for analysis which is acceleration, coasting and deceleration. In the analysis of the energy in the journey, the variation of its consumption is subject to multiple factors because of the difference in operation model and the variation in the track slope data. In view of decreasing unnecessary energy consumption, the equations for train energy consumption and the track parameters are substituted in the teaching-learning-based optimization (TLBO) technique, which can compute the optimal results fast. The optimal results being incorporated in the trains can help reduce unnecessary energy consumption and errors by human operations and arrive at the destination on schedule. By the equations for energy consumption, train parameters, and TLBO, our study proved to be able to reduce energy use as well as ensure of Top Transport Time Expenditure (TTE) of the trains.

From the ship anchoring operation model and evaluation methods point of view, this paper establishes the mathematic evaluation models of ship anchoring operation by using membership functions in the ship handling simulation system, estimates the ship anchoring operation's evaluation index weight based on information entropy under the condition of rough set. The evaluating simulation system of ship anchoring operation is developed with Visual C++, and the tested result is deal.

With the development of the economy and the expansion of market capacity, companies that launching new types of the services need to conduct enterprise location in the newly developed market to serve the customers. In order to maximize the profit, companies should balance the rent and the customer flow volume, as well as service income and customers' waiting cost, which means that the companies should choose right places to provide service. When there are some competitors, optimal service rate should be set to keep the customers staying at the company to get service. In this paper, we use queuing theory to study location problem. A location model with changing arrival rate and an operation model with changing service rate are built. We characterize the optimal policies and discuss the impact of the parameters on the optimal policies. Numerical experiments are conducted to discuss the impact of the customers' patience to the optimal service rate.

This paper proposes a novel steering operation model scheduled by vehicle velocity. The model is constructed via the H ∞ loop shaping and accommodates uncertainty due to individual difference. The analysis by using a driver model is indispensable to design efficiently driver assistance systems that have been focused on recently. Since the driver's operation characteristics vary according to vehicle velocity, the model must be scheduled by vehicle velocity. The proposed steering operation model shows excellent course following performances in lane change simulations.

With the trend of triple play, digital cultural resources have an increasingly significant influence on cultural dissemination, and the management and operation model also become the key point of attention and discussion. This article analyzes the business models which can be used in the aspects of management and operation on digital cultural resources from three different platforms - the Internet, the broadcast networks and telecom networks, and then emphasizes the use of triple play to improve the user's personalized service, and reveals the problems during the operation of business model.

Expatiating on the important functions of the joint operation model in military emulation, discussing the causations of military operations based on UML, bringing forward dynamic frame class and the rule of the modeling, taking the eliminating fraise action in the attack campaign as the example to illuminating.

With the rapid development of e-commerce, a B2T e-commerce operation model emerging internet and group buying has sprung up. After the crazy development and vicious competition in the B2T market, many operators begin to find a way out. That's why they turn to offer localized special services to consumers. Basing on the macro perspective, this article uses “diamond model” to examine the major factors affecting the service B2T e-commerce and also uses coefficient variation to analyze district differences between B2T markets in east, west and central regions. On the basis, it offers some tactics and proposals for promoting domestic B2T market.

Under the influence of economic globalization, transnational investment has improved the development of China's economy. At the same time, it arouses numbers of problems, conflicts and crises. Local industry is suffering an attack which even appears industry safety problems. On the basis of references, it can be concluded that only by deeply understanding the reasons why transnational corporations impact China passively in some aspects can we propose corresponding solutions. Therefore, this essay analyzed the trend of operation model and summed up the negative impact on China's industrial safety and proposed corresponding solutions at last.

Intelligent Universal Transformer is an intelligent and multi-purpose electrical power conversion equipment which is based on power electronic converter. It combines the transformer, inverter, sensors, monitors, phase shifter, reactive power compensator into one, so it has advantages that the traditional transformer can not have. This article analysis the works of the Intelligent Universal Transformer systematic and elaborated operation model of the Intelligent Universal Transformer in detail. It also studies the control method of Intelligent Universal Transformer in deep and developed the DSP control system which based on TMS320C28343.This article conducts the running and controlling simulation based on the 10KV/500V transformer and gives the simulation results of the control of 10KV/500V Intelligent Universal Transformer. Theoretical analysis and simulation results verify its effectiveness and feasibility.

With the rapid development of social economy, the society water consumption has increased dramatically which also lead to sharp contradiction between supply and demand, so how to allocate limited water resources reasonable has become a reality and urgent task of water management. With the author further studying the reservoir regulation theory and mechanism, the deterministic optimization is developed based on multi-objective optimizing reservoir scheduling model, using nonlinear programming as optimization algorithm for constructing the universal optimizing reservoir scheduling model. And based on multi-objective thought, it has produced a set of Pareto frontier solution set, through the temple, the application of EPing hydropower station get a series of decision-making plan, so that policymakers can choose the preference for decision-making plan.

With a rapid development of the Chinese economy, there is a huge amount of logistics costs, while China still has not established a pallet associates, and even it has not proposed a practical model of the pallet associates yet. Therefore, the model of Chinese pallet associates is proposed based on the analysis of banking operations as well as the loan of money and the comparison of pallet lease. Meanwhile, proposing an operation model for pallet associates, in which also refers to the bank operation pattern and practical experience, as well as proposing the pallet associates construction strategy. Finally, in order to realize the exchange of information system and high efficiency of network operation management, the concept of using RFID technology to research and develop the pallet associates management information system will be described in full details.

Product warranties have become an integral part of many manufacturers' and retailer's marketing strategies. Some organizations promote extended warranties since they have high profit margins. This paper deals with the relationship and difference between basic product warranties and extended warranties, and analyzes the operation model of extended warranties. On the basis of identification and classification the risks in operation of extended warranties, the paper offers some suggestions to management of extended warranties from the angle of manufacturers.

During last decades, consumption of natural gas has been continuously increasing worldwide. Hence, infrastructure has been developed to transport the natural gas from the well to the final consumer. Natural gas chain value can be segmented in upstream and downstream sectors. The organization of the upstream sector is similar to that of the oil sector, whereas the organization of the downstream sector resembles much that of the electricity sector. The frontier between both sectors is usually placed in the international borders. Specifically, the operation model focuses on the downstream sector. The supply activity and the utilization of the different infrastructure such as the liquefied natural gas terminal or the storage facilities are considered. The upstream sector is not completely ignored as it is characterized in the supply activity. The operation model can be a support for taking decisions in the medium term on behalf of involved companies in the gas market as illustrated by the case study.

Successive years have witnessed our economy's sustainable and speedy growth; meanwhile, we have also accumulated a lot of problems, such as severe waste of resources and energies and grave environmental disruption, which hamper greatly our future development. As a kind of innovative economic operation model, circular economy proposes new content and requests for enterprise behaviour. This paper exploits the objects, principles and characteristics of enterprise behaviors under the mode of circular economy, applies game theory on their motives and expounds the importance of circular economy to the further development of an rational enterprise.

Eachers and students are our main clients in the university hospital, what kind of the building we need to load the university hospital system in the new era. This article based on the hospital of the China University of Petroleum (qingdao), to summarize the difference compared to the other hospitals based on the analysis of the clients, operation model and emergency system.