Volume LXII Number 2/2010

Papers submitted: 21

pre-review phase: 21 reviews
1st review phase: 42 reviews; 18 accepted papers; 3 not accepted
2nd review phase: 18 reviews; 15 accepted papers; 3 not accepted
3rd review phase: 15 reviews; 10 accepted papers; 5 not accepted

 Binary Image Compression Based On Binomial Numbers
 Olexey Borysenko, Igor Kulyk, Sergiy Kostel, Olena Skordina 
  pg. 1-12 
 In this paper we present a method of information compression that is based on the transition from a binary sequence to its serial number in the binomial number system. At the first stage of the binomial compression the transition from an even-weight code sequence to a corresponding binomial number is carried out, then at the second stage the binomial number is transformed to its serial number accordingly the numerical function of the binomial number system with the given parameters. Before the binomial compression ordinary binary sequences are accounted even-weight code combinations since computing their number of binary units. In the paper the initial binary sequences are strings or substrings, columns or subcolumns of binary images. The paper expounds the method of binary images compression based on the binomial numbers. The considered method has simple image compression and decompression algorithms, which are presented in detail in the paper. An estimation of the compression method is implemented. The presented example shows how to compress a binary image with the help of the method of compression based on binomial numbers, generated by binomial number systems.
 A Common Fixed Point Theorem for Two Pairs of Maps Satisfying the Property (E.A)
 Mohamed Akkouchi 
  pg. 13-19 
 In 2003, K. Jha, R.P. Pant and S.L. Singh have established in [5] a common fixed point for two pairs of compatible maps under a contractive condition of Meir-Keeler type and Lipschitz type condition. In 2008, this theorem was extended by H. Bouhadjera and A. Djoudi (see [3]) to two pairs of weakly compatible maps without using continuity. The aim of this paper is to extend the results of [5], [3] and others to the case of two pairs of occasionally weakly compatible mappings such that one of them is satisfying the property (E.A). Here, we drop the Meir-Keeler type condition and keep only the Lipschitz type condition, which, if the Lipschitz constant k  1=5, then it is not a contractive condition of the classical type. So our approach provides some new results to the field of metric fixed point theory.
 Restoration of Old and Deteriorated Well-Loggings
 Ionut Lambrescu 
  pg. 20-27 
 In the oil industry (and not only here), for old rigs, an important volume of classical loggings are still kept and used. This information can be digitized in order to be further processed. A number of software products deal with this digitization. One of the problems is the sometimes poor quality of the old loggings (some of them more than 50 years old). The paper presents some techniques used to improve the quality of the scanned loggings, as a prerequisite for a successful digitization. The main idea is to isolate the curves and the gridlines, process these images separately and then reunite them again, in an improved RGB image. The processing consists in a succession of morphological operations performed on the curves and gridlines images.
 The Hall Effect Experiment Using New Data Acquisition and Processing Methods
 Zoltan Borsos, Anca Baciu, Mihai Hotinceanu, Ion Simaciu, Liviu Dumitrașcu, Georgeta Nan 
  pg. 28-35 
 The Hall Effect, in all its variants (classic, quantum or fractional quantum), is one of the effects that revolutionized certain areas of physics, not only theoretically but also in technological terms, for example the development of sensitive magnetometers. The observation and study of all characteristic properties for this effect, in laboratory and under optimum conditions, involve the development of a complex experimental assembly. Also, when introducing teaching criteria for an optimal presentation of the Hall effect for both students and specialists attending training courses, etc (to better know, understand and retain), we must consider additional issues such as those related to laboratory work implementation. The experimental data collection can be done in several ways. The classic version of the experimental setup includes analog measurements devices and the reading of the studied quantities values is done visually. Automatic data acquisition in electronic form can be achieved only if we have an interface between the experimental setup and the computer. In this article, we propose such a complex experimental assembly, which is able to acquire and to process experimental data in real time by using COBRA 3 dedicated software. After data set acquisition, we can also send (live or after being processed) this database or processed information for direct or later presentations. There are also presented the advantages and disadvantages of the two variants of the experiment, both in terms of experiment performing and in terms of teaching methods quality.
 An Expert System for a Wastewater Treatment Plant Effluent Quality Assessment
 Madalina Carbureanu 
  pg. 36-45 
 To improve the effluent quality in accordance with the European and Romanian technical normative, in Ploieşti there will be built a new wastewater treatment plant with both the mechanical and biological steps, including the sludge treatment with an improved technology in pollutants’ removal. In literature, there are presented expert systems developed for wastewater treatment domain, being outlined fields of interest such as: plant monitoring, plant control and diagnosis, plant designing and decision support. Because of the strict effluent standards used today in wastewater treatment domain, the treatment processes become increasingly complex, so the knowledge of the plant operators is not sufficient for an optimal running of it. Due to the fact that the experts’ knowledge in wastewater treatment can be introduced into the plant afferent system through a knowledge base, which may contain knowledge about past events, abnormal events etc., the usage of expert systems with other instruments can be a useful tool for a better plant activity. The quality of the plant effluent has a major impact on the quality of the emissary and generally on the environment, therefore the effluent’s periodical assessment is necessary, in order to identify the treatment process problems and to correct them just in time. In this paper, there will be developed a prototype expert system to assess the quality of Ploieşti wastewater treatment plant effluent, using VP-Expert, an expert system shell.
 A Decomposition of m-Continuity
 Takashi Noiri, Valeriu Popa 
  pg. 46-53 
  By using an m-space (X;mX), we define the notions of gm-closed sets and m-lc-sets and obtain a decomposition of m-continuity. Then, the decomposition provides a kind of decomposition of weak forms of continuity.
 N-Frequency Undulator
 Liana Sandru, Valentin Ioan Remus Niculescu, Sorin Miclos, Alina Ionescu 
  pg. 54-59 
 Free-electron lasers (FEL) imply the elaboration of insertion devices. Generation of synchrotron radiation uses storage rings and free electrons laser components. In this type of insertion devices the motion of relativistic electrons generates tunable coherent radiation with desired wavelength. A beam of relativistic electrons undergo transverse oscillation and emit radiation. In FEL research and development one of the main trends is the elaboration of the compact devices. The undulator is the principal component where the phenomenon of coherent radiation takes place. The quality of the beam and of the resulting radiation can be improved by trying different field patterns, coil pitches, dimensions (tapering). The models evolved from single-frequency longitudinal scheme to two-frequency transversal, then to three-frequency transversal and now with a general form of N-frequency model. This expansion form a single frequency to multiple frequencies responds to a practical need. Many applications, in diverse areas as biology, pharmacy, chemistry, metamaterials and others, require several beams with different frequencies in order to get selective interactions with the matter. A new undulator magnetic structure for free electron lasers is presented. For the N-frequency undulator and injection on the longitudinal axis, the trajectory of electrons is computed. This structure reduces the peak value of the magnetic field component
 Common Fixed Points for Multifunctions Satisfying a Polynomial Inequality
 Alexandru Petcu 
  pg. 60-65 
  Common fixed point theorems in complete metric spaces (X, d) are given for two or more multifunctions which satisfy polynomial inequalities using only the distance d, without using the Hausdorff metric.
 Automatic Evaluation of Scanned Multiple Choice Tests
 Bogdan Ionete, Ionut Lambrescu 
  pg. 66-71 
 Although on-line or off-line multiple choice test are used, in many cases, traditional on paper tests are still in use. If we deal with large amount of tests, their evaluation becomes a problem. The paper presents a technique of digitization of scanned multiple choice tests, including their evaluation. A three steps approach is considered: first, the scanned image is preprocessed in order to improve its quality, then character recognition phase assures the acquisition of the data that identifies the applicant and reads, and the final phase scores the test. A test by test processing or a batch procedure is possible. The method produces accurate results and has many applications in day by day activities
 Has Open Source Prevailed in Desktop Grid and Volunteer Computing?
 Monica Vladoiu 
  pg. 72-79 
 Grid Computing provides for using resources that are both geographically and administratively distinct, which can be reached over the computer network such as processing power, storage capacity, specific data, input and output devices, etc. Individual users may access computers and data transparently, without having to consider location, operating system, account administration, etc. that are abstracted from them. Desktop grid and volunteer computing systems are one major category of grid systems, in which cycles are scavenged from idle desktop computers, either within an intranet or over the Internet. In this paper we will address the question whether the usage of desktop grid and volunteer computing systems to compute-intensive projects is influenced or not by their open source-ness. We overview here briefly the main such systems and show their main characteristics, emphasizing their most important strengths and weaknesses. Our major concern is the impact of the open source-ness of these desktop grids on their life span and their use scale within projects worldwide. Our opinion is that the answer to the question in paper’s title is “yes”, and that open source software is a natural choice for desktop grid and volunteer computing, as well as for modern research, because it encourages successful integration, cooperation and boosting of new ideas.