bluuebunny/crossref_metadata_2025 huggingface dataset:
A declining trend of hepatitis A and hepatitis E at tertiary care hospital in South Gujarat
Authors: Gandhi Twinkle Nareshchandra , Patel Swati Sugnesh , Chaudhary Apurva , Nakrani Kalpesh
Published: April 2024

Objectives:

Hepatitis A virus (HAV) and Hepatitis E virus (HEV) both are spread through the fecal-oral route and cause acute viral hepatitis (AVH) and pose a major public health problem in India. This study was done to find out the proportion of positivity of HAV and HEV in patients with AVH and its seasonal trend.

Materials and Methods:

A retrospective study was carried out at Surat Municipal Institute of Medical Education and Research Medical College, Department of Microbiology, Surat, Gujarat. Result of 3615 blood samples of suspected AVH patients of the past 5 years (January 2018–December 2022) were taken from hospital data records. The enzyme-linked immunosorbent assay method was used to test serum samples for immunoglobulin M (IgM) HAV and IgM HEV antibodies for HAV and HEV, respectively. All samples were evaluated for liver function as well.

Results:

The positivity of HAV and HEV was 15.13% and 10.26%, respectively. The coinfection rate was 2.07%. HAV and HEV both affected males more than females. Among pregnant females, HEV infection had more positivity (6.77%) than HAV, which had 1.08% positivity. HAV and HEV infections had a seasonal trend, with the highest infection rate in the monsoon.

Conclusion:

The declining trend of cases of HAV and HEV was found in Surat city of south Gujarat which indicates increased awareness about hepatitis among people and better public health management by the civic authorities.
Associate Support and Development Strategies
Authors: Badal Alen
Published: April 2024

Innately, supporting and developing a new hire or seasoned associate, regardless of the industry, represents two mutually exclusive events. In short, support by all stakeholders shall be evident and genuine before development strategies are executed and achieved by associates. This process also supports professional development and support for those involved in the support and development of associates. Specifically, managers and leaders often require support and development with this process regardless of their experience and/or education levels. The intent of this study is to provide support strategies for leaders and managers, alike, to implement within their respective organization, regardless of the type of business, profit or non-profit, industry etc. Discussions in this study will revolve around two varied sectors: education (non-profit) and corporation (for-profit).
Value relevance of IFRS adoption in the deposit money banks in Nigeria
Authors: Modibbo Abubakar , Salihu Ndagi , Usman Aliyu
Published: April 2024

The prime role of financial statements is to provide information that is useful to existing and potential investors, creditors and other users in making rational investment and similar decisions. Accounting information is a product of Generally Accepted Accounting Principles (GAAP), standards and other institutional settings which are presumed to shape the form and content of the financial reports. Uniform accounting standards assist investors and other market participants to effectively analyze firms from countries with accounting standards that they are familiar with and that IFRSs are adopted in order to achieve information of higher quality than local standards. Value relevance is one of the most common methods of examining the quality of accounting information. Information has the quality of relevance when it influences the economic decisions of users. This study examined value relevance of accounting information after the mandatory IFRSs adoption in the Nigerian Banking industry. Correlational research design using pre-and-post IFRSs regime analysis in a sample of 15 banks for a period of 8 years (2008-2015) was employed. Panel regression technique of data analysis was used and the study found that the adoption of IFRS has significantly improved the value relevance (decision usefulness) of accounting information of deposit money banks in Nigeria during the period covered by the study. However, the results show that the adoption of IFRS improves the value relevance of book values of equity and accounting earnings significantly. We recommend that accounting regulators should investigate the implementation credibility of IFRS in the Nigerian banks.
Endovascular Repair of Infrarenal Aortic Penetrating Ulcer in a Colon Cancer Patient: A Case Report
Authors:   Department of General Surgery, Lincoln Medical Center, USA, Khrisat; Tarek , Gart Alexander ,   Department of Vascular Surgery, Columbia University, USA
Published: April 2024

This is a 66-year-old woman, active smoker, with history of severe bilateral peripheral arterial disease, recently diagnosed with colon cancer. During evaluation patient was found to have an asymptomatic penetrating infrarenal aortic ulcer complicated with aneurysm and intramural hematoma formation. This is an interesting case that highlights the importance of recognizing complicated aortic ulcers, pattern of progression, due to their increased risk of aortic rupture and the option of endovascular repair of infrarenal ulcers. This is an interesting case that presents some of the rare metastatic patterns of breast cancer, which can include the orbit, and hematologic abnormalities due to spinal mets. Breast cancer is reported to be responsible for most ophthalmic mets, with it being the primary neoplasms of origin of 40% of the metastases to the orbit.
الحس مصدرًا للمعرفة- دراسة نقدية عقلية لتجريبية جون لوك
Authors: مصطفى علي , محمد صالح آماد
Published: April 2024

يهدف البحث إلى عرض الرؤية التجريبية عند رائد فلسفتها في العصر الحديث الإنكليزي جون لوك، كونه المنظر لها، وكل من جاء بعده إنما هم آخذون منه فلسفته تلك، ولأن الفلسفة التجريبية تعتبر الفلسفة المهيمنة على الساحة الفلسفية والعلمية في العالم الغربي في الوقت الحالي، وتكاد تصبح العدسة الوحيدة التي يرى من خلالها الغرب العالم، وما لهذه الفلسفة من أهمية وتأثير على الرؤية الغائية للإنسان وعلاقته بالعالم سواء في بعده الفيزيقي أو الميتافيزيقي كان لا بد -والحال هذه- من عرض شفاف ومتوازن لأبرز حججها ومحاولة تقديم نقد بنَّاء لها من قِبَل خصومهم العقلانيين، وذلك في نقد عقلي لهذه الفلسفة من وجهة نظرنا، في دراسة تحليلية نقدية، مستعينًا بأدلة عقلية تجريبية، وملزمًا للطرف المقابل القائل بالتجريبية بلازم قوله. وتم التوصل إلى أن الفلسفة التجريبية القائلة بأن المعرفة الحقة إنما هي من خلال التجربة والحواس فحسب تحمل عوامل نقضها داخليًا، كونها لا تستطيع أن تثبت دعواها من خلال التجربة، مما يعني أنها لا تعتبر المصدر الوحيد الموثوق للمعرفة، كما أن جون لوك يؤمن بتجريبية معينة للعقل دور فعال وأساسي في تحديد ملامحها، منكرًا للضرورات العقلية الأولية، ومثبتًا في الوقت نفسه وجود الخالق والشعور بالذات الإنسانية، والتي تعتمد في طيات استدلالها قانون السببية الفطري. بالإضافة إلى أن التجربة معتمدة بالضرورة على استقراء ناقص تقيس الغائب على الشاهد في الحكم، فيمكن -أقلها إمكانًا عقليًا- أن تُرفض كونها مجرد تجربة لم تسنح الفرصة لإيجاد أمثلة مخالفة لها فحسب، وعليه فاليقين الذي ينشده جون لوك ممتنع. والدراسات المسحية الأنثروبولوجية التي أجريت على الأطفال أثبتت أنهم في مراحل مبكرة جدًا يدركون المبادئ الفطرية ووجود كائن أسمى وإن لم تكن هذه المفاهيم محددة لديهم ودون معرفة ماهيتها، فهو إدراك عملي لا نظري.
Promoción de salud mental en estudiantes de Nátaga y La Plata Huila
Authors: Villada Ramírez Adriana Carolina , Galindo Torres Ángela Rocío , Velásquez Sandoval Laura Alejandra , Ramírez Rivera Laura Lizeth , Cáceres Laura Valentina , Castillo Medina María Paula
Published: April 2024

Este proyecto se planteó para el fortalecimiento de la autoestima de ochenta estudiantes entre 15-19 años de ambos sexos que cursaban grado once en dos instituciones de los municipios de La Plata y Nátaga, Huila, con la finalidad de promover su salud mental, la cual se verá reflejada en un buen rendimiento académico. Por lo tanto, su desarrollo tuvo dos fases; en primer lugar, se aplicó la escala de autoestima de Rosenberg para medir el nivel de autoestima de los estudiantes, relacionándolo con el rendimiento académico de los mismos. En segundo lugar, se realizó un plan de intervención en el marco de la promoción de la salud mental, el cual contó con indicadores de proceso y de resultado que garantizaban el proceso de evaluación y monitoreo, dicho plan incluía actividades como talleres de psicoeducación para docentes y padres de familia, dinámicas de actos solidarios, juego de roles, juegos sobre competencias emocionales como un diario de gratitud, autorretratos y actividades lúdico-dinámicas como la denominada “Gincana”.
Durante el periodo de dos meses, tras la implementación del programa de intervención, se aplicó por segunda vez la escala de autoestima de Rosenberg con el propósito de hacer un análisis de los resultados mediante la aplicación Jamovi. A partir de esta, se encontró una significativa correlación entre la autoestima, el rendimiento académico y la capacidad de toma de decisiones. En consecuencia, se interpretó como factor protector para evitar conductas de riesgo, y como un factor de riesgo cuando es débil o ausente.
El desarrollo del proyecto se llevó a cabo con una metodología mixta, con ella, las estudiantes que apoyaron la ejecución del proyecto desarrollaron competencias para la construcción, aplicación y análisis de instrumentos cuantitativos y cualitativos que les permitieron acercarse al conocimiento del fenómeno para poder intervenir.
The Non-Didactic Aspects of e-Learning Quality
Authors: Stemposz Ewa , Jodłowski Andrzej , Stasiecka Alina
Published: April 2024

The paper presents a research on the quality of e-learning from the non-didactic point of view. It illustrates a discussion about measures developed on the basis of statistical analysis of data gathered from e-learners who evaluated the quality of e-learning applications and systems. The main contribution of the paper is the proposal for the quality metrics with the features concerning e-learning platforms in the technological and human aspects.
Analytical Modeling of the WCDMA Interface with Packet Scheduling
Authors: Stasiak Maciej , Zwierzykowski Piotr , Wiewióra Janusz
Published: April 2024

The article presents the application of a new analytical model of the full-availability group carrying a mixture of different multi-rate traffic classes with compression property for modeling the WCDMA radio interface with packet scheduling. The proposed model can be directly used for modeling of theWCDMA interface in the UMTS network servicing different traffic classes. The described model can be applied for a validation of the efficiency of the WCDMA interface measured by the blocking probability and the average carried traffic for particular traffic classes.
Technical and Regulatory Issues of Emergency Call Handling
Authors: Michalski Wojciech
Published: April 2024

The paper presents selected technical and regulatory aspects of emergency call handling in communication between citizens and authorities in case of distress. Among the most important technical aspects of emergency call handling are recognition and treatment of emergency call by originating network, routing of such call to the appropriate public safety answering point (PSAP), delivering call-related information to the PSAP as well as architecture and organization of PSAPs. From the legal point of view, of importance are the obligations for the Member States and stakeholders involved in the E112 project included in the EU directives, actions of European Commission related to providing access to the location information as well as obligations concerning emergency call handling included in Polish national law.
A Microscopic Approach for THz Intersubband Challenges
Authors: Pereira Mauro F.
Published: April 2024

The main candidate to be a practical and low cost high power THz source is the intersubband-based quantum cascade laser, which can have a tremendous impact in many practical applications, including last mile and indoor telecommunication systems. In this review we discuss current challenges for THz intersubband device development from a microscopic point of view. Next summarize the search for new mechanisms and structure designs that can lead to intersubband gain without population inversion. This is a very important topic of current research, since is both an extremely elegant phenomenon from the basic physics of view and crucial for effective lasing in the THz range. The reason is that scattering phenomena can lead to level broadenings of the same order of magnitude of the lasing transitions, making population inversion by carrier injection in upper lasing subbands extremely difficult. Previous work in the literature is compared and contrasted with a new scheme that may lead to high temperature lasing by engineering the nonequilibrium population inversion with a combination of band structure and many body effects mediated by a k-space filter.
Impact of Signaling System Performance on QoE in Next Generation Networks
Authors: Batalla Jordi Mongay , Śliwiński Jarosław , Tarasiuk Halina , Burakowski Wojciech
Published: April 2024

The first experience of quality by multimedia applications’ users takes place during the setup phase of a new connection. If the setup phase is not accepted or “slowly accepted”, the confidence of the user decreases. The user becomes more sensitive when he/she pays the connections with assured quality of service (QoS). In this case, the process of call request should be also accomplished with QoS guarantees. This paper presents the signaling sub-system implemented within the EuQoS system. The EuQoS signaling process follows main assumptions of next generation networks (NGN) architecture and performs tasks related with codec agreement between multimedia end users, admission control and resource reservation functions. In this paper, we present analytical, simulation and experimental results showing the impact of signaling system performance on quality of experience (QoE) for the potential users of multi-layer EuQoS system. In particular, the presented approach aims at ensuring user QoE of the connection setup phase by ensuring QoS for transferring signaling messages by the network.
SOI Technology:An Opportunity for RF Designers?
Authors: Raskin Jean-Pierre
Published: April 2024

This last decade silicon-on-insulator (SOI) MOS-FET technology has demonstrated its potentialities for highfrequency (reaching cutoff frequencies close to 500 GHz forn-MOSFETs) and for harsh environments (high temperature,radiation) commercial applications. For RF and system-on-chip applications, SOI also presents the major advantage ofproviding high resistivity substrate capabilities, leading to sub-stantially reduced substrate losses. Substrate resistivity valueshigher than 1 kΩΩΩcm can easily be achieved and high resistivitysilicon (HRS) is commonly foreseen as a promising substratefor radio frequency integrated circuits (RFIC) and mixed sig-nal applications. In this paper, based on several experimentaland simulation results the interest, limitations but also pos-sible future improvements of the SOI MOS technology arepresented
The Influence of Meteorological Phenomena on Modern Satellite Systems
Authors: Bogucki Jan , Jarkowski Jacek , Wielowieyska Ewa
Published: April 2024

The areas of attention, described in this paper, extend throughout the modern satellite systems. Future satellite systems are to be planned for the millimeter band, which has greater weather attenuation effects than until now used bands. This paper provides a brief overview of propagation factors on millimeter-band earth-satellite paths and requirements in relation to the need for specific types of propagation data.
Trends in Use of RF Spectrum
Authors: Strużak Ryszard
Published: April 2024

This paper reviews possible improvements in the use of radio waves for carrying information from an engineering viewpoint. A few new concepts are proposed, which reduce the problem to an arrangement of solids in a multidimensional space.
History of Semiconductors
Authors: Łukasiak Lidia , Jakubowski Andrzej
Published: April 2024

The history of semiconductors is presented beginning with the first documented observation of a semiconductor effect (Faraday), through the development of the first devices (point-contact rectifiers and transistors, early field-effect transistors) and the theory of semiconductors up to the contemporary devices (SOI and multigate devices).
Novel Method of Improving Electrical Properties of Thin PECVD Oxide Films by Fluorination of Silicon Surface Region by RIE in RF CF4 Plasma
Authors: Kalisz Małgorzata , Głuszko Grzegorz , Beck Romuald B.
Published: April 2024

This study describes a novel technique to form good quality low temperature oxide (< 350°C). Low temperature oxide was formed by N2O + SiH4:N2 plasma in a plasma enhanced chemical vapour deposition (PECVD) system on the silicon surface reactively etched in CF4 plasma (RIE – reactive ion etching). The fabricated oxide demonstrated excellent (for low temperature dielectric formation process) currentvoltage (I−V) characteristics, such as: low leakage current, high breakdown voltage and good reliability. Experimental results indicate that the proposed method of fluorine incorporation into the SiO2/Si inteface improves electrical parameters of MOS structures.
Large-Signal RF Modeling with the EKV3 MOSFET Model
Authors: Chalkiadaki Maria-Anna , Bucher Matthias
Published: April 2024

This paper presents a validation of the EKV3 MOSFET model under load-pull conditions with high input power at 5.8 GHz, as well as S-parameter measurements with low input power up to 20 GHz. The EKV3 model is able to represent coherently the large- and small-signal RF characteristics in advanced 90 nm CMOS technology. Multifinger devices with nominal drawn gate length of 70 nm are used.
Channel Identification Using Chaos for an Uplink/Downlink Multicarrier Code Division Multiple Access System
Authors: Frikel Miloud , Safi Said , Targui Boubekeur , M’Saad Mohammed
Published: April 2024

A scheme of chaotic spreading sequence for multicarrier code division multiple access system (MC-CDMA) iproposed to estimate the transmission channel. This systespreads spectrum and identifies the channel, simultaneously. The proposed scheme uses a chaotic sequence generated by a logistic map as a training signal and estimate channel parameters according to dynamics of the chaotic sequence. Encoding data by chaotic sequences is first built and then the orthogonal codes are used to spread the encrypted data for multiusers scheme. At the reception, first the channel parameters are identified using a training chaotic sequence in order to equalize the received data, and then the encrypted information is decoded for the desired user. The studies reveal that the proposed system (chaos plus orthogonal codes) significantly outperforms the Walsh-Hadamard code spreading in MC-CDMA system. The performance of the system is considered in the multiuser case by means of simulation. The simulation result shows that the proposed chaotic code spreading approach for channel identification achieves significant improvement in the channel identification, comparing to using others training sequence or the least square method.
Performance Comparison of Protection Strategies in WDM Mesh Networks
Authors: Singh Hemant K. , Aggarwal Shreya , Singh Satendra , Mohapatra Baibaswata , Nagaria Rajendra K. , Tiwari Sudarshan
Published: April 2024

Recent development in optical networking employing wavelength division multiplexing (WDM) fulfills the high bandwidth demand applications. Failure of such networks, leads to enormous data and revenue loss. Protection is one of the key techniques, which is used in designing survivable WDM networks. In this paper we compare dedicated and shared protection strategies employed inWDMmesh networks to protect optical networks failure, particularly fiber failure. Dijkstra’s shortest path algorithm is considered for carrying out simulations. The paper compares the performance of protection schemes, such as, dedicated path protection (DPP), shared path protection (SPP) and shared link protection (SLP) schemes. Capacity utilization, switching time and blocking probability are the parameters considered to measure the performance of the protection schemes. Simulation results show that, SPP is more efficient in terms of capacity utilization over DPP and SLP schemes, whereas, SLP offered better switching time than both DPP and SPP schemes. The average call drop rate is minimum for shared path protection scheme and maximum for shared link protection scheme.
Optimization of the Multi-Threaded Interval Algorithm for the Pareto-Set Computation
Authors: Kubica Bartłomiej J. , Woźniak Adam
Published: April 2024

Previous investigations of the authors surveyed the possibility of applying interval methods to seek the Paretofront of a multicriterial nonlinear problem. An efficient algorithm has been proposed and its implementation in a multicore environment has been done and tested. This paper has two goals. First one is to tune the developed algorithm to increase the speedup of the multi-threaded variant. The second one is to extend the algorithm to compute not only the Paretofront (in the criteria space), but also the Pareto-set (in the decision space). Numerical results for suitable test problems are presented.
Socio-Economic Challenges from and for Future Internet
Authors: Wierzbicki Andrzej P.
Published: April 2024

There are several papers available addressing the challenges for Future Internet that result from socio-economic aspects; such challenges must be obviously taken into account when constructing and developing Future Internet. This paper, however, takes an opposite view that from the dynamics of the development of Internet itself (or Future Internet) result challenges for the socio-economic development and even for the paradigm of understanding economy; such challenges must be taken into account first, then – in a feedback loop - lead to the modification of socio-economic challenges for Future Internet. This change of perspective is necessary because the analysis of socio-economic challenges for Future Internet is typically based on a classical paradigm of equilibrium economics. While useful, this paradigm is limited and has been shown incomplete, e.g., by the recent world-wide financial and economic crisis. This paper shows that the informational revo- lution – including but not limited to the development of Internet – has already changed the behavior of main socio-economic agents as well as of economic markets and our understanding of them; thus, new perspectives are needed. The paper also shows that a useful perspective is that not of expected benefits from Future Internet – there are many such benefits and they will surely motivate enough economic development of Future Internet – but of socio-economic threats resulting from the dynamic development of the Internet. There are several such threats and conflicts that can be foreseen: the conflict between corporatization and governance; the conflict between direct and indirect limits to freedom; the trend towards elitarism inherent in Internet development dynamics versus democracy; the threat of network and computer domination over people, etc. Some of such threats and conflicts are discussed in the paper.
Rural Telecommunications Infrastructure Selection Using the Analytic Network Process
Authors: Gasiea Yousef , Emsley Margaret , Mikhailov Ludmi
Published: April 2024

The decisions involved in rural settings are of complex nature, with some aspects compounded by the presence of intangible criteria. Hence, a suitable approach is needed that can produce effective solutions. This paper describes the applicability of a multicriteria decision-making method, specifically the analytic network process (ANP), to model the selection of an appropriate telecommunications infrastructure technology, capable of deploying e-services in rural areas of developing countries. It aims to raise awareness among telecommunication planners about the availability of ANP, and to demonstrate its suitability to enhance the selection process. The proposed model is constructed based on concerned experts’ views of relevant selection criteria and potential technology alternatives. Its network structure caters for all possible dependencies and interactions among criteria and alternatives.
A Framework for Evaluation of Communication Bandwidth Market Models
Authors: Stańczuk Wojciech , Pałka Piotr , Lubacz Józef , Toczyłowski Eugeniusz
Published: April 2024

The article presents a method of analysis of marketbased models for resource allocation in communication networks. It consists of several stages: classification of a market model, generation of input data, data adaptation to a tested model, test calculations and, finally, presentation and interpretation of results. A set of general criteria to assess various models has been proposed. Tests are run using dedicated computer applications, data is stored in open XML-based format originated in the multicommodity market model. Network topologies are derived from the SNDlib library.
Pricing Rules Comparison in the Context of Bandwidth Trade
Authors: Pałka Piotr , Toczyłowski Eugeniusz
Published: April 2024

In this paper we compare two pricing rules in the context of bandwidth trade. Allocation and pricing rules, together with a set of signals received from independent agents, constitute a market mechanism. In the paper we analyze two pricing rules: well known Vickrey-Clarke-Groves rule (VCG) and the parametric pricing rule (PPR).We apply these pricing rules to the allocation rule specified by the balancing communication bandwidth trade model (BCBT).
Bandwidth Trading: A Comparison of the Combinatorial and Multicommodity Approach
Authors: Kołtyś Kamil , Pałka Piotr , Toczyłowski Eugeniusz , Żółtowska Izabela
Published: April 2024

Since the telecommunication market becomes more complex and dynamic, a strong need for a new, efficient and flexible bandwidth trading mechanisms appears. We believe that good mechanisms, that allow effective and fair allocation of bandwidth between market participants will help to develop the real competitive bandwidth market. In this paper we compare two different double-sided bandwidth auction mechanisms, that seem to be well suited approaches for trading indivisible units of bandwidth: combinatorial auction c-SeBiDA and multicommodity mechanism BACBR-I. The c-SeBiDA mechanism considers two types of commodities: inter-node links and paths consisting of particular links. Market participants may bid a single link, or a bundle of links, constituting a specific path. The BACBR-I mechanism is a multicommodity exchange model, that allows bidders to place buy offers not only for individual or bundled links, but rather for end-to-end connections. Therefore, it is the decision model that allocates the most efficient links to connections. We run a large set of experiments to test the allocation and computational efficiency obtained under both approaches.
Coordination Games with Communication Costs in Network Environments
Authors: Nishizaki Ichiro , Hayashida Tomohiro , Hara Noriyuki
Published: April 2024

In this paper, we deal with a coordination game in a network where a player can choose both an action of the game and partners for playing the game. In particular, a player interacts with players connecting through a path consisting of multiple links as well as with players directly connecting by a single link. We represent decay or friction of payoffs with distance as communication costs, and examine the effect of the communication cost on behavior of players in the game and network formation. We investigate properties of equilibrium networks by classifying the link cost and the communication cost, and show diversity of the equilibrium networks.
Performance Analysis of a Bi-Objective Model for Routing and Wavelength Assignment in WDM Networks
Authors: Sim ̃oes Carlos , Gomes Teresa , Craveirinha Jos ́e , Cl ́ımaco Jo ̃ao
Published: April 2024

Establishing end-to-end connections on wavelength division multiplexing (WDM) networks requires setting up lightpaths, defining the sequence of optical fibres and the wavelength in each fibre (the routing and wavelength assignmentproblem) for traffic flow. This paper reviews a bicriteria model for obtaining a topological path (unidirectional or symmetric bidirectional) for each lightpath request in a WDM network, developed by the authors, and presents a performance analysis of the model by considering important network performance measures. An extensive performance analysis of the two bicriteria model is presented, comparing the performance metrics obtained with the monocriterion models using the same objective functions, in five different reference networks commonly used in literature.
A Software Platform for Global Optimization
Authors: Niewiadomska-Szynkiewicz Ewa , Marks Michał
Published: April 2024

This paper addresses issues associated with the global optimization algorithms, which are methods to find optimal solutions for given problems. It focuses on an integrated software environment – global optimization object-oriented library (GOOL), which provides the graphical user interface together with the library of solvers for convex and nonconvex, unconstrained and constrained problems. We describe the design, performance and possible applications of the GOOL system. The practical example – price management problem – is provided to illustrate the effectiveness and range of applications of our software tool.
Query Optimization in Teradata Warehouse
Authors: Gosk Agnieszka
Published: April 2024

The time necessary for data processing is becoming shorter and shorter nowadays. This thesis presents a definition of the active data warehousing (ADW) paradigm. One of the data warehouses which is consistent with this paradigm is teradata warehouse. Therefore, the basic elements of the teradata architecture are described, such as processors parsing engine (PE) and access module processor (AMP). Emphasis was put on the analysis of query optimization methods. There is presented the impact of a primary index on the time of query execution. Furthermore, this paper shows different methods of optimization of data selection, data joins and data aggregation. All these methods can help to minimize the time for data processing. This paper presents experiments which show the usage of different methods of query optimization. At the end some conclusions about different index usage are included.
Iris Recognition System Based on Zak-Gabor Wavelet Packets
Authors: Czajka Adam , Pacu Andrzej
Published: April 2024

The paper proposes a new iris coding method based on Zak-Gabor wavelet packet transform. The essential component of the iris recognition methodology design is an effective adaptation of the transformation parameters that makes the coding sensitive to the frequencies characterizing ones eye. We thus propose to calculate the between-to-within class ratio of weakly correlated Zak-Gabor transformation coefficients allowing for selection the frequencies the most suitable for iris recognition. The Zak-Gabor-based coding is non-reversible, i.e., it is impossible to reconstruct the original iris image given the iris template. Additionally, the inference about the iris image properties from the Zak-Gabor-based code is limited, providing a possibility to embed the biometric replay attack prevention methodology into the coding. We present the final prototype system design, including the hardware, and evaluate its performance using the database of 720 iris images.
Face Tracking and Recognition with the Use of Particle-Filtered Local Features
Authors: Stasiak Łukasz A. , Pacut Andrzej
Published: April 2024

A consistent particle filtering-based framework for the purpose of parallel face tracking and recognition from video sequences is proposed. A novel approach to defining randomized, particle filtering-driven local face features for the purpose of recognition is proposed. The potential of cumulating classification decisions based on the proposed feature set definition is evaluated. By applying cumulation mechanisms to the classification results determined from single frames and with the use of particle-filtered features, good recognition rates are obtained at the minimal computational cost. The proposed framework can operate in real-time on a typical modern PC. Additionally, the application of cumulation mechanisms makes the framework resistant to brief visual distortions, such as occlusions, head rotations or face expressions. A high performance is also obtained on low resolution images (video frames). Since the framework is based on the particle filtering principle, it is easily tunable to various application requirements (security level, hardware constraints).
Rule Based Speech Signal Segmentation
Authors: Greibus Mindaugas , Telksnys Laimutis
Published: April 2024

This paper presents the automated speech signal segmentation problem. Segmentation algorithms based on energetic threshold showed good results only in noise-free environments. With higher noise level automatic threshold calculation becomes complicated task. Rule based postprocessing of segments can give more stable results. Off-line, on-line and extrema types of rules are reviewed. An extrema-type segmentation algorithm is proposed. This algorithm is enhanced bya rule base to extract higher energy level segments from noise. This algorithm can work well with energy like features. The experiments were made to compare threshold and rule-based segmentation in different noise types. Also was tested if multifeature segmentation can improve segmentation results. The extrema rule-based segmentation showed smaller error ratio in different noise types and levels. Proposed algorithm does not require high calculation resources. Such algorithm can be processed by devices with limited computing power.
Relaxing the WDO Assumption in Blind Extraction of Speakers from Speech Mixtures
Authors: Kasprzak Włodzimierz , Ding Ning , Hamada Nozomu
Published: April 2024

The time-frequency masking approach in blind speech extraction consists of two main steps: feature clustering in a space spanned over delay-time and attenuationrate, and spectrogram masking in order to reconstruct the sources. Usually a binary mask is generated under the strong W-disjoint orthogonal (WDO) assumption (disjoint orthogonal representations in the frequency domain). In practice, this assumption is most often violated leading to weak quality of reconstructed sources. In this paper we propose the WDO to be relaxed by allowing some frequency bins to be shared by both sources. As we detect instantaneous fundamental frequencies the mask creation is supported by exploring a harmonic structure of speech. The proposed method is proved to be effective and reliable in experiments with both simulated and real acquired mixtures.
Hidden Signature for DTW Signature Verification in Authorizing Payment Transactions
Authors: Putz-Leszczyńska Joanna , Kudelski Michał
Published: April 2024

Traditional use of dynamic time warping for signature verification consists of forming some dissimilarity measure between the signature in question and a set of “template signatures”. In this paper, we propose to replace this set with the hidden signature and use it to calculate the normalized errors of signature under verification. The approach was tested on the MCYT database, using both genuine signatures and skilled forgeries. Moreover, we present the real-world application of the proposed algorithm, namely the complete biometric system for authorizing payment transactions. The authorization is performed directly at a point of sale by the automatic signature verification system based on the hidden signature.
The Template Selection in Biometric Systems Based on Binary Iris Codes
Authors: Chochowski Marcin
Published: April 2024

Since the variability of data within readings from the same person is intrinsic property of every biometric system, the problem of finding a good representative – the template – was recognized and present since the beginning of biometrics. This problem was solved differently for different biometric types, yet usually the template somehow averages the collected data samples. However, for the iris type, thetemplate is usually just one or a few samples. In this paper we describe the experiments that suggest that the averaging is also justified in case of iris template creation. This is an important fact, which can significantly improve a performance of biometric template protection methods for iris.
Impact of Crosstalk into High Resistivity Silicon Substrate on the RF Performance of SOI MOSFET
Authors: Ali Khaled Ben , Neve César Roda , Raskin Jean-Pierre
Published: April 2024

Crosstalk propagation through silicon substrate is a serious limiting factor on the performance of the RF devices and circuits. In this work, substrate crosstalk into high resistivity silicon substrate is experimentally analyzed and the impact on the RF behavior of silicon-on-insulator (SOI) MOS transistors is discussed. The injection of a 10 V peak-to-peak single tone noise signal at a frequency of 3 MHz ( fnoise) generates two sideband tones of −56 dBm separated by fnoise from the RF output signal of a partially depleted SOI MOSFET at 1 GHz and 4.1 dBm. The efficiency of the introduction of a trap-rich polysilicon layer located underneath the buried oxide (BOX) of the high resistivity (HR) SOI wafer in the reduction of the sideband noise tones is demonstrated. An equivalent circuit to model and analyze the generation of these sideband noise tones is proposed.
Broadband Challenges Acceptance Speech Presented at the Ceremony of Awarding Dr. Hamadoun Touré the Title of Doctor Honoris Causa of Wrocław University of Technology, Poland, 14 of September 2010
Authors: Touré Hamadoun
Published: April 2024

Broadband Challenges Acceptance Speech Presented at the Ceremony of Awarding Dr. Hamadoun Touré the Title of Doctor Honoris Causa of Wrocław University of Technology, Poland, 14 of September 2010
Nociones Básicas de Química General y Orgánica: Conceptos académicos actuales
Authors: Muñoz Murillo José Patricio , Vega Gordillo María Verónica , Ochoa Loor José Ricardo , Alvarado Alvarado Haydee María , López Barrera Alexandra Jenny , Camino Valdez Jaime Andres , Erazo López Dolores Beatriz , Zamora Guevara José Alberto , Grijalva-Endara Ana , Castillo Mendoza Bolívar Enrique , Jiménez Jiménez William Johnny
Published: April 2024

En el vasto panorama del conocimiento humano, la química se erige como una ciencia fascinante y omnipresente, cuyas raíces se entrelazan con la historia misma de la humanidad. Desde los albores de la civilización, el ser humano ha buscado comprender los secretos de la materia y sus transformaciones, dando lugar al nacimiento de la alquimia, precursora de la moderna química. En este contexto, el libro “ Nociones Básicas de Química General y Orgánica” se presenta como un faro de conocimiento, destinado a iluminar el camino de aquellos que desean adentrarse en los misterios y aplicaciones de esta apasionante disciplina. Más que una mera recopilación de datos y teorías, esta obra representa un viaje intelectual, una exploración de los fundamentos y aplicaciones de la química en el mundo contemporáneo. Cada página de este libro es un testimonio del esfuerzo y la dedicación de aquellos que han dedicado sus vidas al estudio y la enseñanza de la química. Desde los primeros indicios de la estructura atómica hasta las complejas interacciones moleculares, el lector será guiado en un viaje fascinante a través de los rincones más íntimos de la materia. A través de sus páginas, el lector descubrirá cómo los átomos se unen para formar moléculas, cómo las sustancias se transforman en reacciones químicas y cómo la química orgánica y inorgánica se entrelazan para dar forma al mundo que nos rodea. Desde los laboratorios de investigación hasta las fábricas de producción, la química impregna cada aspecto de nuestra vida moderna, ofreciendo soluciones a los desafíos más apremiantes de nuestro tiempo. Más allá de su valor como texto académico, “Nociones Básicas de Química General y Orgánica” representa un tributo al poder del conocimiento y la curiosidad humana. En un mundo cada vez más complejo y globalizado, la comprensión de los principios fundamentales de la química se vuelve indispensable, no solo para los científicos y tecnólogos, sino también para todos aquellos que buscan comprender y transformar el mundo que nos rodea. Por tanto, es con gran satisfacción y humildad que presentamos este libro al lector, confiando en que sea recibido con el mismo entusiasmo y gratitud con que ha sido concebido. Que esta obra sirva como guía y fuente de inspiración para todos aquellos que se embarquen en el apasionante viaje del descubrimiento químico.
Study of water channels and gates to improve water wheel performance
Authors: Widira Eldwin , Sedyowati Laksni , Prihatiningsih Bekti
Published: April 2024

Glintung Water Street (GWS) in Malang City harnesses water flow in its canal to drive water wheels for electricity generation. However, the discharge of water has not been optimized, necessitating the design of the canal and sluice gate to maximize discharge while mitigating flooding risks. This research aims to determine the optimal design and operational system of the sluice gate to minimize backwater impact. Data collection involved observational techniques and literature review, including hydrology, map, and hydraulic data. Results indicated that the required discharge for the micro-hydro power plant (PLTMH) in the Glintung Water Street (GWS) area was 88 liters or approximately 0.088m3/s. The primary channel's flow rate was measured at 0.104 m3/s, with planned channel inflow at 0.088 m3/s. The sluice gate effectively prevented backwater impact, as water levels did not surpass the sluice height. Planning involved a sluice gate made of mild steel plate (100 cm x 100 cm) with a door height of 200 cm and a thickness of 0.18 cm, operated by a handlebar with a diameter of 2 cm. In conclusion, the backwater effect on the primary channel's water level was minimal, affirming the efficacy of the designed sluice gate.
Optimizing firm value: the impact of intellectual capital with competitive advantage
Authors: Widayanto Aditya Dwi Ramadhan , Harmono Harmono , Apriyanto Gaguk , Hidayatullah Syarif
Published: April 2024

Managing firm value becomes crucial for ensuring shareholder interests. Investors rely on company information, particularly financial reports and ratios, to gauge performance before making investment decisions. Intellectual capital and competitive advantage emerge as key factors influencing firm value. This research aims to provide empirical evidence that intellectual capital has a significant effect on firm value with competitive advantage as a moderator. This study focuses on pharmaceutical companies listed on the Indonesia Stock Exchange. There are 12 such companies. We selected them based on having complete audited financial reports for the past 5 years. We collected data from audited financial reports of pharmaceutical companies listed from 2017 to 2021. The results suggest that the intellectual capital variable does not affect firm value. Meanwhile, partial testing carried out on indicators of intellectual capital found that only capital employed efficiency had a significant effect on firm value. Competitive advantage as proxied by inventory turnover does not affect firm value. However, competitive advantage as proxied by receivable turnover can have a significant influence on firm value.  The research results show that managing intellectual capital efficiently will give rise to competitive advantage which has the impact of increasing firm value.
The Hilbert problem in a half-plane for generalized analytic functions with a singular point on the real axis
Authors: Shabalin P. L. , Faizov R. R.
Published: April 2024

This article analyzes the inhomogeneous Hilbert boundary value problem for an upper half-plane with the finite index and boundary condition on the real axis for one generalized Cauchy–Riemann equation with a singular point on the real axis. A structural formula was obtained for the general solution of this equation under restrictions leading to an infinite index of the logarithmic order of the accompanying Hilbert boundary value problem for analytic functions. This formula and the solvability results of the Hilbert problem in the theory of analytic functions were applied to solve the set boundary value problem.
Some estimates for elliptic systems generalizing the Bitsadze system of equations
Authors: Baizaev S. , Barotov R. N.
Published: April 2024

This article explores an elliptic system of n equations where the main part is the Bitsadze operator (the square of the Cauchy–Riemann operator) and the lower term is the product of a given matrix function by the conjugate of the desired vector function. The system was analyzed in the Banach space of vector functions that are bounded and uniformly H¨older continuous in the entire complex plane. It was revealed that the problem of solving the system in the specified space may not be Noetherian. An example of a homogeneous system with an infinite number of linearly independent solutions was given. As is known, for many classes of elliptic systems, the Noetherianity of boundary value problems in a compact domain is equivalent to the presence of a priori estimates in the corresponding spaces. In this regard, it is important to study the issues related to the establishment of a priori estimates for the system under consideration in the above space. In the case of coefficients weakly oscillating at infinity, necessary and sufficient conditions for the validity of the a priori estimate were found. These conditions were written out in the language of the spectrum of limit matrices formed by the partial limits of the coefficient matrix at infinity. Specific examples were provided to illustrate how the limit matrices are constructed and what the above conditions look like.
On the stability of a particular class of one-dimensional states of dynamic equilibrium of the Vlasov–Poisson electron gas
Authors: Gubarev Yu. G. , Kotelnikova M. S.
Published: April 2024

The one-dimensional problem of the linear stability of dynamic states of local thermodynamic equilibria with respect to small perturbations was studied for the case when the Vlasov–Poisson electron gas contains electrons with a stationary distribution function that is constant in physical space and variable in a continuum of velocities. The absolute instability of all considered one-dimensional dynamic states of any local thermodynamic equilibrium was proved using the direct Lyapunov method. The scope of applicability of the Newcomb–Gardner–Rosenbluth sufficient condition for linear stability was outlined. An a priori exponential estimation was obtained for the rise of small one-dimensional perturbations from below. Analytic counterexamples to the spectral Newсomb–Gardner theorem and the Penrose criterion were constructed. Earnshaw’s theorem was extended from classical mechanics tostatistical one.
A key exchange protocol based on the ring Bn(R, P)
Authors: Nasrutdinov M. F.
Published: April 2024

A key exchange protocol over a special class of formal matrices Bn(R, P) was proposed. The potential of this design for constructing key exchange protocols using suitable associative rings and ideals over them was shown.
Combined strategies for managing the securities portfolio structure
Authors: Sevodin M. A.
Published: April 2024

The possibilities of combining known techniques for optimizing the securities portfolio (SP) structure were studied. A method was introduced that enables the simultaneous use of both passive and active approaches to managing the SP structure. The combined application of these methods is based on techniques for SP diversification and searching for an SP structure that mirrors the SP structure of an index fund. The objective function was modified in order to optimize the SP structure according to the traditional “return–risk” approach. The proposed objective function, along with the security risk, describes the degree to which the desired distribution of SP shares coincides with the distribution generated using an index fund. It was established that the main properties of optimal SPs obtained with the “return–risk” approach also occur in the case under consideration.