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Ergonomics For People With Disabilities

Design For Accessibility

Aleksandra Scientific editors: Polak-Sopinska, Jan Królikowski and Magdalena Technical editor: Wróbel-Lachowska

Open access

Alireza Abbasi and Ali Jaafari

Abstract

In this study, we investigated the quantity and impact of worldwide research production in the field of “project management” over the past 38 years. We performed a bibliometric analysis using the Scopus database between 1980 and 2017 to develop an understanding of the evolution of research on “project management.” Using the knowledge of a domain expert in the field of “project management,” we first compiled a set of reliable keywords, which represented the field. Second, we developed a data extraction strategy for searching the phrase “project management” in the title or keyword or abstract of publications by limiting our sources to journals in English. We observed the evolution of this field by analyzing not only the quantity of publications but also their impact (citations) per year and compared their growth trend in four periods. The results of our analysis confirmed that not only the research themes or topics but also the active parties involved in project management research have experienced phonemic changes over time.

Open access

Oluseun Adetola Sanuade, Abayomi Adesola Olaojo, Adesoji Olumayowa Akanji, Michael Adeyinka Oladunjoye and Gabriel E. Omolaiye

Abstract

This geophysical study was carried out to determine the occurrence of phosphate nodules in the Oshoshun Formation of the Dahomey Basin, Southwestern Nigeria. The electrical resistivity method, comprising 1D vertical electrical sounding (VES; using Schlumberger array) and 2D geoelectrical imaging (using Wenner array), was used to determine the nature and depth of occurrence of the phosphate nodules. Six profile lines were established within the study area, and inverted sections were generated from the apparent resistivity data using DIPRO inversion algorithm. Five VES points were also acquired in the study area, and Win-Resist programme was used to process and interpret the field resistivity data. Four pits were dug along the profiles to verify the interpreted results. The results obtained by both techniques reveal similar geoelectric units: the top soil, clay, clayey sand and clay at different depths. These layers host pockets of phosphate nodules (78–≥651 Ωm) with varying thicknesses. The strong correlation between the lithology profiles obtained from the pits and the interpreted results of the inverted apparent resistivity sections demonstrates the efficacy of the electrical resistivity method in characterising phosphate occurrence within the formation.

Open access

Oluseun Adetola Sanuade, Akindeji Opeyemi Fajana, Abayomi Adesola Olaojo, Kehinde David Oyeyemi and Joel Olayide Amosun

Abstract

A geostatistical approach was used to model porosity of OBA field in onshore area of Niger Delta using simulation technique. The objective is to understand the spatial distribution of porosity and characterize the degree of heterogeneity of underlying formation. Porosity data from twenty-two wells were loaded into SGeMS software. Univariate statistical analysis, experimental semivariogram and Sequential Gaussian Simulation (SGS) were applied on the data. The data was close to normal approximation of Gaussian based of the results of univariate statistics. However, to construct and model horizontal and vertical semivariograms, the data was log-normalized to reduce the coefficient of variation and to get good fit of the model. Parametric semivariogram model shows the range of 72–6480 m, nugget effect of 0.006 and sills of 0.0095, 0.0099 and 0.0111. Six realizations were generated using SGS algorithm and the results suggest that any one of the realizations can independently represents the true picture of the subsurface geology within the study area. Ranking of realizations shows realization 6 as the best and realization 2 as the lowest. This model could

Open access

Tolga Yuret

Abstract

Citation performance of a publication depends heavily on its academic field. Some words in keywords, titles, and abstracts of publications may be indicative of their academic field. Therefore, analysis of differences in citation performance of these words helps us understand inter-field differences in citation performance. In this article, we analyzed citation performance of publications that contain certain words in their keywords, titles, and abstracts in Web of Science from 2010 to 2012. We found that some words do not have a consistent performance. For instance, publications that use a certain word in their keywords have a different average performance compared to publications that use the same word in their titles. Next, we investigated keywords, titles, and abstracts separately. We laid out the words that have the lowest and highest average citations. Words that contain animal names, country names, and mathematical concepts are among the worst performers. Words that contain terminology specific to a scientific field and have relatively lower frequency are among the best performers.

Open access

Demokaan Demirel

Abstract

Performance is a fundamental tool that improves results oriented on public administration. Performance management applications have become very popular in public institutions over the past 20 years. Direct accountability to the political institutions and the public is ensured by defining the performance of public administrations according to their organizational goals and objectives. Local governments are using performance management practices to assess the quality of public services offered. In the United Kingdom, performance management practices at the local level were promoted under the leadership of the central government. However, there cannot be a certain standardization or stability in performance management applications. The Best Value (BV) regime was applied primarily in England and Wales. The system was later applied in Scotland in 2003. In 2002, Comprehensive Performance Assessment (CPA) Programme was introduced. Wales preferred to stay outside of this program. The Wales Programme for Improvement (WPI) has adopted self-assessment and holistic assessment. After 2009, the cost-effectiveness of local services was evaluated through comprehensive area assessments. This practice was abolished after 2010, adopting a governance approach based on the common negotiations of local actors. This study aims to evaluate the performance measurement systems applied in the local area in the United Kingdom.

Open access

Jolanta Słoniec and Reyes González Rodriguez

Abstract

The article compares the reasons for using IT outsourcing (ITO) in Polish and Spanish enterprises, based on the authors’ own research. The reasons for the application of ITO have been classified into three groups: economic, technological, and organizational/strategic. On the basis of the classified reasons, a research hypothesis was formulated: Representatives of Polish enterprises assess other groups of reasons as the most important motivation for the use of ITO in their companies compared to Spanish enterprises. On the basis of the authors’ own research, the hypothesis has been confirmed. Polish enterprises assess technological reasons as the most important, whereas Spanish enterprises consider organizational/strategic reasons to be the most important, although the differences in the assessment are not large. The difference in the validity of the reasons for the use of ITO may arise from the maturity of the ITO market in both countries but may also result from the personal experience of the companies with ITO.

Open access

Tomasz Tarczewski, Michal Skinski, Lech M. Grzesiak and Marek Zieliński

Abstract

The article presents modern PMSM servo-drive with SiC MOSFETs power devices and microprocessor with ARM Cortex core. The high switching frequency is obtained due to the application of high efficient power switching components and powerful microprocessor. It allows to achieve good dynamical properties of current control loop, proper disturbance compensation and silent operation of servo-drive. Experimental tests results obtained for two different control schemes (i.e., cascade control structure and state feedback position control) are presented.

Open access

Emrah Zerdali and Murat Barut

Abstract

This paper aims to introduce a novel extended Kalman filter (EKF) based estimator including observability analysis to the literature associated with the high performance speed-sensorless control of induction motors (IMs). The proposed estimator simultaneously performs the estimations of stator stationary axis components of stator currents and rotor fluxes, rotor mechanical speed, load torque including the viscous friction term, and reciprocal of total inertia by using measured stator phase currents and voltages. The inertia estimation is done since it varies with the load coupled to the shaft and affects the per formance of speed estimation especially when the rotor speed changes. In this context, the estimations of all mechanical state and parameters besides flux estimation required for high performance control methods are performed together. The performance of the proposed estimator is tested by simulation and real-time experiments under challenging variations in load torque and velocity references; and in both transient and steady states, the quite satisfactory estimation performance is achieved.