Semih Bilgen

National PQ Monitoring Network for Turkish Electricity Transmission System

In this paper a nationwide power quality monitoring system, which computes and collects PQ parameters and the required waveforms at a power quality monitoring center for both the purposes of early warning and later analysis of power quality of the whole transmission system, is presented. The system consists of three basic units: PQ monitors connected to various transformer substations all over the country; a national PQ monitoring center which communicates with all PQ monitors regularly, receives PQ data and archives them; and finally a client software, which lets individuals connect to the national PQ center and run searches on the PQ archive. The monitors compute PQ parameters based on the IEC Standard-61000-4-30. The client software will be available to the Electricity Transmission System Corporation of Turkey, TEIAS, distribution companies, large industrial plants which are directly supplied from the transmission system, research institutes and the universities. This is a three-year project of the Scientific and Technological Research Council of Turkey, TUBITAK, which started in March 2006 and the already-developed prototype system is presented in this paper.

A framework for qualitative assessment of domain-specific languages

Domain-specific languages (DSLs) are used for improving many facets of software development, but whether and to what extent this aim is achieved is an important issue that must be addressed. This paper presents a proposal for a Framework for Qualitative Assessment of DSLs (FQAD). FQAD is used for determining the perspective of the evaluator, understanding the goal of the assessment and selecting fundamental DSL quality characteristics to guide the evaluator in the process. This framework adapts and integrates the ISO/IEC 25010:2011 standard, CMMI maturity level evaluation approach and the scaling approach used in DESMET into a perspective-based assessment. A detailed list of domain-specific language quality characteristics is elaborated, and a novel assessment method is proposed. Two case studies through which FQAD is matured and evaluated are reported. The case studies have shown that stakeholders find the FQAD process beneficial.

Remotely Powered Underwater Acoustic Sensor Networks

The remotely powered underwater acoustic sensor networks (RPUASN) paradigm is introduced, whereby sensor nodes harvest and store the power supplied by an external acoustic source, indefinitely extending their lifetime. Necessary source characteristics are determined. Feasibility is illustrated with realistic examples, and open research issues are pointed out. Performance of RPUASN is directly related to the sensing coverage and communication connectivity over the field the sensor nodes are deployed. The required number of RPUASN nodes and the volume which is guaranteed to be covered by the nodes are analyzed in terms of electrical power, range, directivity, and transmission frequency of the external acoustic source, and node power requirements.

Distributed Restoration in Optical Networks using Feed-forward Neural Networks

Abstract.A new method is proposed for determining protection paths in an optical network where users have different characteristics in terms of reliability needs and security restrictions. Survivability is achieved by distributed mesh protection. Over the preplanned primary and backup capacity, optimal routing and wavelength assignment is carried out. In case of a network failure, protection routes and optimum flow values on these protection routes are extracted from a previously trained feed-forward neural network which is distributed over the optical data communications network.

Process based information systems evaluation: towards the attributes of “PRISE”

Purpose – The purpose of this paper is to demonstrate the importance of undertaking a systemic view of information systems evaluation that augments the frequently reported prescriptive (cost/benefit) analysis approaches.Design/methodology/approach – The paper adopts a qualitative case perspective and derives a framework for substantive information systems evaluation factors (PRISE). Three empirical formulations are considered and a comparison made to determine the content and context of the findings.Findings – The findings support the flexibility and relevance of PRISE as a framework for information systems evaluation. It notes the objectives, relations and components for explicitly identifying the outputs required to make a valid assessment of the systems.Research limitations/implications – The study is limited contextually where attention should be made not to generalise the findings beyond the empirical findings within the case analysis. Further studies may usefully include the main features of PRISE b...

AiOLoS: A model for assessing organizational learning in software development organizations

Context: In an industry in which technological developments are rapid, in order to keep up with the continuously increasing competition and to obtain competitive advantage, the software development organizations (SDOs) need to obtain the correct knowledge, use it efficiently and pass it to future projects evolving it accordingly. Objective: The main aim of this paper is to propose a novel model, AiOLoS, for assessing the level and characteristics of organizational learning (OL) in SDOs. Method: The primary contributions of this two-legged AiOLoS model are the identification of the major process areas and the core processes that a learning software organization (LSO) follows during its OL process and to provide the necessary measures and the corresponding definitions/interpretations for the assessment of the learning characteristics of the SDO. The research is supported with a multiple case-study work to identify the mapping of the core processes and the applicability of the AiOLoS model to SDOs, its utilization as a tool for assessing OL and providing a basis for software process improvement (SPI). Results: The case studies have shown that not only the AiOLoS measures are applicable to SDOs but also that they measure in great extent the actual OL that is realized in the organization and that the major process areas and core processes are actually related to the OL process of SDOs. Conclusion: AiOLoS has been designed to provide a starting point for the enhancement of OL capabilities of SDOs, which in turn should provide a basis to conduct SPI activities. Therefore, it is also important to investigate a possible binding of AiOLoS to SPICE and the inclusion of a maturity dimension to AiOLoS.

A model for tonal context time course calculation from acoustical input

Abstract This paper presents a two‐stage model that calculates tonal context as a continuous function in time. The model is capable of processing acoustical polyphonic inputs. The first stage is a simple note recogniser that produces pitch‐class note output corresponding to the acoustical input. A bank of leaky integrators constitute the second stage. The integration rates and saturation limits of these integrators vary with each musical event according to the relations among input notes and the candidates of tonal centre. User controllable parameters enable musical memory time span control. The output of the model is the tonal context vector retaining normalised values of the leaky integrators with each integrator holding the strength value of a specific tonal centre.

Modelling and Assessment of the Effectiveness of Government Information Technologies: Value Space Approach with a Public Sector Case Study in Turkey

In the context of evaluating effectiveness of information systems, the public sector requires a specific approach for measuring indirect benefits such as strategic / political value. There is not yet a holistic approach and no unified adaptive and time‐variant model addressing the problem. A model for assessing both initiatives and ex‐post benefits is needed. In this paper, we describe the Strategic Management Model, developed and partially applied at the Ministry of Finance, Turkey. The model merges public value, strategic goals, service delivery value chain, performance indicators, continuous monitoring and evaluation, and asset management concepts in the Public Financial Management Value Space. This is compliant with Government Finance Statistics, which is the basis for our Public Financial Management Value Space, with dimensions, in which every node and path is defined as an object within this value space. This adaptive model will allow multi‐dimensional assessment, enabling backward traceability, establishing the necessary links between the performance, goals and budget.

A framework for reviewing domain specific conceptual models

Conceptual models are used in understanding and communicating the domain of interest during analysis phase of system development. As they are used in early phases, errors and omissions may propagate to later phases and may be very costly to correct. This paper proposes a framework for evaluating conceptual models when represented in a domain specific language based on UML constructs. The framework describes the main aspects to be considered when conceptual models are represented in a domain specific language, presents a classification of semantic issues and some evaluation indicators. The indicators can, in principle, identify situations in the models where inconsistencies or incompleteness might occur. Whether these are real concerns might depend on domain semantics, hence these are semantic, not syntactic checks. The use of the proposed review framework is illustrated in the context of two conceptual models in a domain specific notation, KAMA. With reviews based on the framework, it is possible to spot semantic issues which are not noticed by case tools and help the analyst to identify more information about the domain.

Agility Problems in Traditional Systems Engineering - A Case Study

Well-established systems engineering approaches are becoming more inadequate as today’s systems are becoming more complex, more global, more COTS/re-use based and more evolving. Increased level of outsourcing, significant amount of subcontractors, more integration than development, reduced project cycles, ecosystem like collaborative developments, software product lines and global development are some of the changes in the project life cycle approaches. In this paper, we present the results of an exploratory case study which tries to identify the agility problems in large scale software intensive defense projects. This is the first step of our research in which the overall objective is to improve the agility attributes of the traditional systems engineering approach.