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The goal of the article is to compare efficiency of solving a problem of determining satisfiability of logical formulas SAT (3-SAT), which belongs to a class of NP-complete problems, either by using simple genetic algorithms or using genetic algorithms with suggested modified mechanism of stepwise adaptation of weights (SAW). Two possible ways of dealing with constraint - either based on a penalization...
In recent years the reassessment of remuneration schemes for renewable sources in several European countries has motivated the increase of wind power generation participation in electricity markets. Moreover, the continuous growth of wind power generation, as well as the evolution of wind turbines technology, suggests that wind power plants may participate in both energy and ancillary services markets...
The foundation of a data processing engine running on a large cluster is its programming model that defines data processing operations and data movements. A special kind of communication activities that are not normally defined in the programming model but are often used in ad hoc ways in system development, is called out-of-band communications. The existing ad hoc solutions of out-of-band communications...
Because of the rapid growth of open source software, how to choose software from many alternatives becomes a great challenge. Traditional ranking approaches mainly focus on the characteristics of the software themselves. In this paper we investigate the market demands for software engineers, and propose a novel approach for ranking software by analyzing the market requirements for special software...
Due to the increasing penetration of distributed generation and new high-power consumption loads - such as electric vehicles (EVs) - distribution system operators (DSO) are facing new grid security challenges. DSOs have historically dealt with such issues by making investments in grid reinforcement. However, an alternative solution, enabled by the expected roll-out of smart meters and high penetration...
Sequenced and nonsequenced semantics were introduced as different semantics for the evaluation of an operation in a temporal database such as a query or data modification. In this paper we present a new framework that shows both semantics are variants of a general temporal semantics. Our framework uses tuple lineage to track tuples through operations. We present the general semantics and show additional...
The increasing use of renewable energy sources and distributed generation brought several changes to the power system operation, with huge implications to the competitive electricity markets. With the eminent implementation of microgrids and smart grids, new business models able to cope with the new opportunities are being developed. Virtual Power Players are a new type of player, which allows aggregating...
Staff turnover is one of the most pressing problems in enterprises' staff management. The former studies on the problem of staff turnover did not succeed timely in the managing, supervising and preventing of the staff on the production line that have great turnover flow. Taking the staff data of the chain retail stores of the C-R Group as an example, collecting all the information of the staff at...
According to an academic research, when an enterprise runs longer, their strategies are more prone to gain support by other businesses. Leaning on the durability and the longevity, such enterprises can accumulated their credits and stabilize the business. Consequently, the span variable of the total business-running time or the variable of growth rate and the price variable of stock exhibit a negative-proportion...
There has been a hot debate both in the academia and in the manufacturing sector as to whether the success recorded in the privatisation of the Nigerian telecommunication sector can be replicated in the power sector. This paper therefore sets out to determine the consumer perception of the electric power infrastructure in Nigeria. Two sets of questionnaire totalling 500 were administered, the method...
This paper aims to contribute to the existing body of knowledge regarding the organizational context variables to be considered in designing a rewards system geared towards fostering innovation in products at organizations. Based on the existing literature, a preliminary reference chart is created using context variables and their implications for the design at issue, specifically: organizational...
Web application usage has grown in the past few years. As a result more and more transactions are taking place via the web. Attacks have grown in sophistication and number. A database is a favorite target of attackers. As a result key challenge is to protect data privacy and prevent data theft. In this paper, a Hybrid Intelligent Database Security framework is proposed. The focus of the framework...
A new type of linguistic summaries, so-called contextual linguistic summaries, are further developed. The point of departure are contextual bipolar queries which play the same role for a new type of summaries as flexible fuzzy queries do with respect to the classical linguistic summaries. The bipolar queries employed are of a special type, following the required/desired semantics formalized using...
The distribution generation and demand response remuneration practices, used by most aggregation entities, considers simple characteristics as the type of resource. This evaluation may cause a non optimized tariff definition in most cases. For this paper, a Virtual Power Player as aggregator is considered, which is able to make clusters of both producers and consumers. The proposed methodology defines...
The variability of large scale wind power generation at high penetration levels has a significant impact on the secure and economic operation of onshore power systems. Grid bottlenecks, high gradients and wasting of wind energy can be avoided using local Energy Storage Systems (ESS) with dedicated power and capacity. The storage type considered in this study is an adiabatic compressed air energy storage...
Grounded in users' online purchasing behaviors, we developed a multi-attribute sorting panel for online shopping and incorporated opinion attributes in it. Furthermore, the multi-attribute sorting panel was expanded to three alternative designs that mainly differ in the way of eliciting relative importance for attributes, called direct assessment, indifference method, and indirect measurement. Then,...
Demand response can to be used in order to reduce energy consumption or, in an economic standpoint, to avoid the need of more expensive energy resources. The present paper proposes a methodology that makes possible to compare the modeling of distinct demand response programs by having different consumer remuneration approaches. The methodology, which is developed in the scope of a Virtual Power Players...
Large shareholders' tunneling can affect executive incentive contracts. We divide the executive incentive into explicit compensation and implicit incentive. Data from publicly listed companies in China during 2008–2013 shows that tunneling leads to decline in executive pay-performance sensitivity. In addition, tunneling also leads to significant increases in position-related consumption. The results...
The promotion method can effectively improve the enterprises' economic efficiency or not, it is a question that all enterprises are concerning. Taking economic value added (EVA) as the evaluation index for the promotion effect, it can really reflect the operating results of enterprises, pay attention to the sustainable development of the company, promote enterprises to implement more effective promotion...
The use of distributed generation and demand response programs in smart grids implies management and integration of these resources when they are interconnected with the main power system. In the present paper, it is defined a methodology that can be used by the Virtual Power Player in order to aggregate and schedule the resources. The aggregated producers and consumers are optimally managed, making...
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