Ion Lungu

Bucharest Academy of Economic Studies | ASE

Using automated capital investment software systems is a common task today. At the beginning of the third millennium, modern investors are using artificial intelligence resources and methods to find the best investment opportunities on capital markets and to process the trading orders. One of the most important aspects of this activity, besides the...

Trading the financial markets is a common idea nowadays. Millions of market participants, individuals, companies or public funds are buying and selling different equities in order to obtain profit from the buy and sell price difference. Once the equity was established, the main question marks are when to buy, when to sell and how long to keep the o...

This paper presents an extended version of the article “Forecasting solutions for photovoltaic power plants in Romania” that has been accepted and successfully defended at The 15th International Conference on Informatics in Economy (IE 2016). The installing of photovoltaic power plants (PVPPs) is increasing rapidly in Romania. The national power gr...

In this paper, we have developed a series of neural networks in order to design a decision support system for predicting, analysing and monitoring the performance indicators in the field of renewable energies in Romania. We have first analysed a series of comparative aspects regarding the algorithms used for developing the neural networks: the Leve...

Taking into account the well-known benefits of using renewable energy as an important energy source, some practical aspects regarding operation must be underlined. In the specific case of wind power plants (WPP) forecasting the generated wind power is the most important issue for assuring stability of Romania's National Power System (NPS) and econo...

In this paper different aspects regarding smart metering systems integration have been depicted. Smart metering systems, renewable energy sources integration and advanced tariff systems implementation require informatics solution that could automatically collect and process data, forecast the behavior of electricity consumers, analyze trends regard...

Integration of renewable energy sources mainly implies several advanced technologies such as smart metering devices, implementation of advanced tariff systems, informatics systems for load profile analyses and decision making on electricity consumption, etc. At electricity consumers' level, smart metering devices along with load profile calculation...

While the exploitation of the renewable resources takes more ground, especially internationally, also in Romania we can identify some major projects in the field of renewable energy, considered of great interest nowadays. As we talk of an environment with low predictability, stimulating investors can be achieved by using decision support systems wi...

Increasing energy demand, the current problems of global climate change and the interaction of political and economic interests in the energy markets determine governments, researchers and professionals to be more aware of energy use. The European Union established the ambitious objective for the year 2020 to lower energy consumption by 20%, improv...

eographical Information Systems are used in solving many regional development related problems, around the world. Starting from some national programs to famous international ones, such as INSPIRE program, each such initiative uses geospatial data as well in the process of building regional development strategies. This paper presents the main techn...

Traffic simulators based on microscopic models are a detailed approach to infrastructure and policy evaluation. They allow a closer to reality representation of the factors that influence traffic flow: individual driver and vehicle attributes, dynamic route decisions, lane changing and restrictions, driver cooperation. Such aspects add to the compl...

The paper presents the main characteristics of a cloud-based e-learning system, by comparing it to other e-learning architectures like service-oriented architecture, event driven architecture, distributed computer. The first part of the paper shows these architectures and the way they fit to e-learning systems. The second part describes the main te...

In this paper, we have researched the possibility of using graphics processing units (GPUs) for generating a variety of random numbers. We have compared the performance obtained on the latest GPUs architectures with the one recorded on a high-end central processing unit, we have analyzed the main features of each architecture that influence the per...

Finance-related problems require more and more computations; therefore, the problem of finding efficient implementations for option pricing models on modern architectures has become an important challenge. Although there are numerous implementations of the Monte Carlo method on central processing units, many of them face limitations arising from th...

Query optimization is one of the most important problems in databases. Query optimization can be talked about in different scenarios with different tools and different results. In this paper we'll talk about query processing and optimization and test strategies in different context, starting from simple queries continuing with correlated queries, j...

In this paper, we first briefly describe some mathematical aspects regarding the computation of eigenvalues, followed by an original approach: a bisection algorithm useful in computing eigenvalues for a tridiagonal symmetric matrix of arbitrary size, using the computing capabilities of the latest graphics processing units that incorporate the Compu...

This paper identifies the characteristics of a wind farm and the influence factors for these, grouped by the objective function, the input parameters, the nature of parameters and the criteria they apply for, i.e. the objective function, the input parameters, the optimal value, the nature of parameters and the criteria. It proposes an algorithm for...

The emerging world-wide e-society creates new ways of interaction between people with different cultures and backgrounds. Communication systems as forums, blogs, and comments are easily accessible to end users. In this context, user generated content management revealed to be a difficult but necessary task. Studying and interpreting user generated...

Developing intelligent systems in public institutions such as the Power Grid Companies require efficient methods in order to support better decisions. The Power Grid Companies must fundament their investment decisions by estimating all the benefits and costs during the life cycle of a wind power plant. In order to estimate the financial feasibility...

The purpose of an informational system is to reflect the business it is supposed to assist. This is the reason why the informational system needs a representation of the business objects that are involved in the processes and also the business rules that are applied to the business objects. Every object is simpler than we can think and also more co...

Starting from the need to develop efficient IT systems, we intend to review the optimization methods and tools that can be used by SQL Server database administrators and developers of applications based on Microsoft technology, focusing on the latest version of the proprietary DBMS, SQL Server 2008. We’ll reflect on the objectives to be considered...

In this paper, we depict some of the most widely used data mining algorithms that have an overwhelming utility and influence in the research community. A data mining algorithm can be regarded as a tool that creates a data mining model. After analyzing a set of data, an algorithm searches for specific trends and patterns, then defines the parameters...

Executive Information Systems are designed to improve the quality of strategic level of management in organization through a new type of technology and several techniques for extracting, transforming, processing, integrating and presenting data. In order to build analytic reports for Executive Information Systems (EIS) in an organization we need to...

A Geographic Information System can be used in order to store, analyze and predict data regarding wind parks. Such data can refer to the natural factors that can affect the wind turbines, the placement of the turbines or their power capacity. In this paper we discuss the possibility to manage wind parks in Romania, based on the wind speed and altit...

In this paper we are analyzing the performance of XML processing in different scenarios involving receiving large quantity of such documents. We are analyzing the loading and processing speed in four different scenarios involving an adapter written in an universal programming language and a relational database.

Phishing has grown significantly in volume over the time, becoming the most usual web threat today. The present economic crisis is an added argument for the great increase in number of attempts to cheat internet users, both businesses and private ones. The present research is aimed at helping the IT environment get a more precise view over the phis...

The authors of this article are going to bring into light the significance, the place and the role of information systems in the university education process. At the same time they define the objectives and the target group of the subject named Economic Information Systems and state the competence gained by students by studying this subject. Specia...

Developing Decision Support Systems in public institutions such as the National Power Grid Companies require applying very efficient methods in order to support the decisions. The decision support system in the National Power Grid Companies can integrate the energy prediction achieved by some data mining algorithms that help managers to fundament t...

The investment of public institutions in wind power plants or in any type of power plants implies the necessity to justify their financial feasibility. This is done by estimating all the benefits and costs during the life cycle. In order to estimate the revenues, we need to know with certain accuracy the output of these power plants. In the case of...

The shape memory alloys possess attractive characteristics as actuation elements. They are capable of transforming thermal energy into mechanical work. This paper presents our results in developing a modular linear and rotary family of shape memory alloy actuators, designed in several dimensions, in order to actuate high performance precision engin...

Often, Business Intelligence Systems (BIS) require historical data or data collected from var-ious sources. The solution is found in data warehouses, which are the main technology used to extract, transform, load and store data in the organizational Business Intelligence projects. The development cycle of a data warehouse involves lots of resources...

In this article we will present a practical solution for building an integration tier between an online trading platform and two stock exchange markets, in a SOA like architecture. We will present, in the space constraint of an article, how a solution can be build using XML, Java and PL/SQL and not third-party costly solutions. This approach, even...

This article is an extended version of a paper presented in the WSEAS MCBE09 conference in which we will present in more detail practical solution for building an integration tier between an online trading platform and two stock exchange markets, in a SOA like architecture. Our solution is constructed using XML, Java and PL/SQL and not third-party...

The development cycle of a decision support system involves many resources, time and high cost and above all, the database schema used in the system is built only for some specific tasks. So, a relational database schema or a data warehouse prototype cannot be easily mapped and reused in multiple DSS projects. In this paper we propose an object-ori...

The development cycle of a decision support system involves many resources, time and high cost and above all, the database schema used in the system is built only for some specific tasks. So, a relational database schema or a data warehouse prototype cannot be easily mapped and reused in multiple DSS projects. In this paper we propose an object-ori...

The first part of the paper treats the general problems concerning the shape memory alloy actuators and their operation principle. Then, our work referring to the developing a modular family of linear and rotational actuators, realized in many typo dimensions, in a compact design, with facile connection with the actuated mechanisms and supplying mo...

The database systems have nowadays an increasingly important role in the knowledge-based society, in which computers have penetrated all fields of activity and the Internet tends to develop worldwide. In the current informatics context, the development of the applications with databases is the work of the specialists. Using databases, reach a datab...

In this paper we describe our study on organic topic recognition and knowledge extraction from online documents. Firstly we will introduce the current state of information extraction with ontology support then we will present our approach, corpus, theoretical background, algorithm, experiments and research goals. At the end we will draw some conclu...

In time, the integration needs of companies increased. Even though not taken very seriously, integration solutions in general, and portals in particular, slowly become leaders in turning new principles into practical experiences. In the beginning, portals focused on aggregating, organizing, and indexing unstructured data, but modern portals now do...

Often, Business Intelligence Systems (BIS) require historical data or data collected from var-ious sources. The solution is found in data warehouses, which are the main technology used to extract, transform, load and store data in the organizational Business Intelligence projects. The development cycle of a data warehouse involves lots of resources...

As a high level development environment, the Java technologies offer support to the development of distributed applications, independent of the platform, providing a robust set of methods to access the databases, used to create software components on the server side, as well as on the client side. Analyzing the evolution of Java tools to access dat...

In order to improve the quality of Business Intelligence Systems in an organization we can choose to build the system using BI techniques such as OLAP and data warehousing or by using traditional reports based on SQL queries. The cost and developing time for BI tools is greater than those for SQL Reports and these factors are important in taking de...

Integration within public institutions is useful in better aligning the IT with the core processes, but also helps the various parts of the business work with each other better, enabling important business strategies like straight-through processing, improved public service through singe-view-of-customer portals, business activity monitoring and hi...

The Business Intelligence project's team is always confronted with a major problem: low performance in data extraction from data warehouses. This problem can be critical because of the major impact in the using the data from data warehouse: if a BI report is taking a lot of time to run then it is useless or the data displayed are no longer availabl...

Since its introduction, Extensible Markup Language (XML) has evolved and helped us evolve in the way which we think about structuring, describing, and exchanging information. The ways in which XML is used in the software industry are many and growing. For example, for Web services the importance of XML is crucial; all key Web service technologies a...

In this paper we performed a basic and common DBA tasks on the two products and measured the time taken and the steps required to complete each task, to assess their relative manageability. The time taken to complete the tasks was then weighted according to their frequency of use in a typical DBA workday to arrive at an overall time savings percent...

Oracle Human Resources (Oracle HRMS) represents a strong set of applications for the optimization of the human capital an organization disposes of. In the new economy, based on the Internet, the optimum usage of work force is one of the imperatives in e-business. In order to successfully meet this target, an organization needs a simple and efficien...

The problem of low performance in data extraction from data warehouse can be critical in the Business Intelligence projects because of the major impact in the using the data from data warehouse: if a BI report is taking a lot of time to run or the data displayed are no longer available for taking critical decisions, the project can be compromised....

The volume of data and numerous applications developed within a company can often generate a redundancy difficult to control. In the same time, the homogeneous or heterogeneous management systems of the companies become overcharged for obtaining useful information from databases. For this reason, the organizations develop specialized systems for th...

In time, portals have evolved to meet the integration needs of companies. Even though not taken very seriously, they have slowly become leaders in turning new principles into practical experiences. In the beginning, portals focused on aggregating, organizing, and indexing unstructured data, but modern portals now do much more. Portal software conti...

The article approaches the subject of business intelligence in the context of ERP projects, and presents the experience of a real industry project, its development and the problems it faced. It offers an insight into the main three phases of the project and it analyses the impact of technical problems and of company changes on the BI project, revea...

The present paper is meant to describe the finite differences methods necessary to determine the value of financial options. In addition is presented the mathematic model of rating European type options. Value determination of an option is made through solving an equation with derivatives. Finding the analytical solutions is not at hand, reason for...

In order to improve the quality of Management nformation Systems in an organization we can choose to build the system using Business Intelligence techniques such as OLAP and datawarehousing or by using traditional reports based on SQL queries. The cost and developing time for BI tools is greater than those for SQL Reports and these factors are impo...

In today's economy access to quality information is a top requirement in any competitive organization. Managers want real-time information, in a desired format and at a convenient price. Lately, as a result of the new informational technologies (hardware and software) that are enabling the building of cheaper and faster informational systems, more...

The Executive Information Systems (EIS) are designed to improve the quality of strategic level of management in organization through a new type of technology and several techniques for extracting, transforming, processing and presenting data in order to provide strategic information. These technologies are known as Business Intelligence Tools. This...

In order to build analytic reports for Decision Support Systems (DSS) in an organization we can choose to do it by using Business Intelligence techniques such as OLAP and data warehousing or by using traditional reports based on SQL queries. The cost and developing time for BI tools is greater than those for SQL Reports and these factors are import...

Today, the environment based on informatics influences continuously auditors’ work, because it creates new opportunities and new risks, additional rules in what concerns security, fairness and acceptable margin of error. The growth of the systems’ complexity, especially the informatics accounting Systems of ERP type (Enterprise Resource Planning),...

The information system for administrating and distributing color images through the Internet ensures the consistent replication of color images, their storage - in an on-line data base - and predictable distribution, by means of a digitally distributed flow, based on Windows platform and POD (Print On Demand) technology. The consistent replication...

Executive Information Systems are design to improve the quality of strategic level of management in organization through a new type of technology and several techniques for extracting, transforming, processing, integrating and presenting data in such a way that the organizational knowledge filters can easily associate with this data and turn it int...

On-line transaction processing systems (OLTP) is profoundly different from dimensional data/warehouse, the basis for open decision support systems. Both OLTP and datawarehouse systems are greatly concerned with data consistency However OLTP consistency is microscopic. The point of transaction processing is to proces a very large number of atomic tr...

The Internet is the perfect tool that can assure the market’s transparency for any user who wants to trade on the stock market. The investor can have access to the market news, financial calendar or the press releases of the issuers. A good online trading platform also provides real-time intraday quotes, trading history and technical analysis giv...

This research presents the main elements of query optimizations in distributed systems. First, data architecture according with system level architecture in a distributed environment is presented. Then the architecture of a distributed database management system (DDBMS) is described on conceptual level followed by the presentation of the distribute...

Options are nowadays transacted within a lot of stock exchanges worldwide. The problem of options gets a special importance due to the fact that many of the managerial decisions can be assimilated to options. The paper deals with numerical methods of financial options evaluation. The mathematical model of determining the values of an option of Euro...

The main objective of EIS (Executive Information Systems) is to provide in real time representative informations to the high-level management. EIS is a subset of a class of technology solutions that also are referred to in the industry as Business Intelligence (BI) software. EIS provide solutions to support strategic activities such as goal setting...

The paper suggests the presentation of aspects concerning the informatization strategy for the control activity at the Romanian Court of Counts. The introduction of the audit assisted by computer through the accomplishment of an IT system and the required training of the personnel represents a priority in the short time and CCR medium strategy.

In this paper, we analyze solutions for optimizing the data parallel prefix sum function using the Compute Unified Device Architecture (CUDA) that provides a viable solution for accelerating a broad class of applications. The parallel prefix sum function is an essential building block for many data mining algorithms, and therefore its optimization...

In the last thirty years the idea of Decision Support System(DSS) generated in the same time a lot of expectations and a lot of speculations and frustrations too. Although there was a fast development of the electronic equipment, managers often felt disappointed about their trails to use information technologies for the decision process (the electr...

Business Intelligence (BI) is a last hour informatics technology which focuses on the organization, functioning and managing an industry with the help of calculating techniques. The development of the industry on the market environment, but also on the digital context, has served as solid experience for accumulating necessary knowledge in the BI fi...

This research presents the main methods of database fragmentation in distributed systems. First, the steps of the distributed database design are presented. Then the fragmentation rules and the fragmentation types is described followed by the presentation of a mixed fragmentation methodology for initial distributed database design based on a graphi...