Reliability (Measurement and Evaluation)

Testing software for assessing or improving reliability presents several practical challenges. Conventional operational testing is a fundamental strategy that simulates the real usage of the system in order to expose failures with the highest occurrence probability. However, practitioners find it unsuitable for assessing/delivering high reliability levels, and they do not see the adoption of a “real” usage profile estimate as a sensible idea, being it a source of non-quantifiable uncertainty. Debug testing techniques aim to expose as many failures as possible, but regardless of their impact on runtime reliability. These strategies are used either to assess or to improve reliability, but cannot improve and assess reliability in the same testing session. This article proposes Reliability Assessment and Improvement (RELAI) testing, a new technique thought to improve the delivered reliability, by an adaptive testing scheme, while providing, at the same time, a continuous assessment of reliability attained through testing and fault removal. The technique also quantifies the impact of a partial knowledge of the operational profile. RELAI is positively evaluated on four software applications compared, in separate experiments, with techniques conceived either for reliability improvement or for reliability assessment, demonstrating substantial improvements in both cases.

The Egen Klassifikation Scale version 2 (EK2) is an important functional ability assessment scale for nonambulant neuromuscular patients. We investigated the validity and reliability of the EK2 scale in Turkish Duchenne muscular dystrophy (DMD) and spinal muscular atrophy (SMA) patients. Forty-one patients were included in the study. An intra/interobserver reliability study of the EK2 scale as translated into Turkish was performed. The Brooke Functional Classification Scale (BFC) for Upper and Lower Extremities, 10-item Modified Barthel's Index for Activities of Daily Living (MBI), and Pulmonary Dysfunction Index (PDI) were used to investigate the validity of the Turkish version of the EK2 scale. Cronbach's alpha was 0.81 and ICC was 0.87 with a 95% confidence interval (r=0.92, p<0.01). There were positive, moderate correlations between the EK2 sum score and the BFC upper extremity level and between the EK2 sum score and the PDI, and a negative, moderate correlation betwe...

In 1975, Melzack developed the McGill Pain Questionnaire (MPQ), which is composed of four major parts and evaluates the quality of pain. Objective: The aim of this study is to assess the reliability, and validity of the MPQ on a sample of Turkish general population.
METHODS: This study used the data from a Web-based questionnaire. This has been administered to 342 participants.
RESULTS: The results indicate that the scale is reliable (r = 0.887). Four factors with Eigenvalues over one have been extracted after evaluating the factor analysis. This has accounted for 62.3% of the variance. Correlations between sensory and evaluative subscales have been low (r = 0.436, p < 0.01), and the most positive correlation has been seen between the miscellaneous and sensory (r = 0.656, p < 0.01), as well as affect subscales (r = 0.601, p < 0.01). Discriminate validity has been evaluated by comparing the patient and control group’s scores. For miscellaneous (p = 0.002) and affect (p = 0.006) subscales statistical differences have been found. The correlations between MPQ (subscales and all scale) and Visual Analogue Scale point has been calculated with Spearman correlation for divergent validity. The correlation between VAS and Pain Rating Index for the patient group has been moderate (rho = 0.59, p = 0.000) and low for the control group (rho = 0.32, p = 0.000). For both groups, most strong correlation with the Visual Analogue Scale has been seen for the affect and evaluation subscales of MPQ.
CONCLUSION: These results support the Turkish-MPQ as a reliable and valid measure for evaluating the quality of pain in the Turkish population. Turkish MPQ can be used in clinical researches to follow and to evaluate the patients.

This chapter is devoted to introducing the theories of interval algebra to people who are interested in applying the interval methods to uncertainty analysis in science and engineering. In view of this purpose, we shall introduce the key concepts of the algebraic theories of intervals that form the foundations of the interval techniques as they are now practised, provide a historical and epistemological background of interval mathematics and uncertainty in science and technology, and finally describe some typical applications that clarify the need for interval computations to cope with uncertainty in a wide variety of scientific disciplines.

Keywords. Interval mathematics, Uncertainty, Quantitative Knowledge, Reliability, Complex interval arithmetic, Machine interval arithmetic, Interval automatic differentiation, Computer graphics, Ray tracing, Interval root isolation.

Recommended Citation:

Hend Dawood. Interval Mathematics as a Potential Weapon against Uncertainty. In S. Chakraverty, editor, Mathematics of Uncertainty Modeling in the Analysis of Engineering and Science Problems. chapter 1, pages 1-38. IGI Global, Hershey, PA, 2014. ISBN 978-1-4666-4991-0.

The final publication is available at IGI Global via http://dx.doi.org/10.4018/978-1-4666-4991-0.ch001

The purpose of this study was to examine specific aspects of the reliability and validity of Age Band 1 of the Movement Assessment Battery for Children-Second Edition (MABC-2) (Henderson, Sugden, & Barnett, 2007) in Greek preschool children. One hundred and eighty-three children participated in the study; the children ranged in age from 36 to 64 months old (Μ = 50 months, SD = 9 months). Test-retest reliability of the MABC-2 was evaluated using intraclass correlation coefficient (ICC). Cronbach’s alpha for the items of each motor domain was estimated to determine internal consistency. Confirmatory factor analysis was used to examine the factorial validity of the MABC-2 test. Correlation coefficients among individual item scores and the total score were also calculated to further examine validity. The ICC for all test items was good, except for the drawing trail task, which was moderate. Cronbach’s alpha coefficient values were .51, .70 and .66 for manual dexterity, aiming and catching, and balance, respectively. In the confirmatory factor analysis, goodness-of-fit indices suggested a satisfactory fit of the data to the model. The correlation coefficients between each test item and the total score were moderate. The results suggest that the MABC-2 can be a reliable and valid tool for the assessment of movement difficulties among 3- to 5-year-old children.

Keywords: motor assessment, psychometric properties, DCD

The aim of this study was to develop a three-tier concept test to determine high school students' conceptual understanding in terms of chemical bonding, and at implementing a reliability and validity study for the test. A total of 175 high school students participated in the research. A three-tier test of 15 questions was employed in the study. Expert opinion was consulted for content and face validity. Furthermore, false positive and false negative values were also calculated for content validity, and on average these values were found to be less than 10%. Statistical analyses were performed for construct validity; Cronbach's Alpha coefficient was calculated as 0.74. To perform item analysis, the top 27% of the students and the bottom 27% of the students were determined. As a result, it was found that item difficulty indices ranged between .47 and .77, and that the discrimination indices were above .30. Following the analyses, both item difficulty indices and discrimination indices were found to be adequate. At the end of the study, Chemical Bonding Concept Test was considered to be reliable and valid.

Objective: Boredom has been defined as " the aversive experience of wanting, but being unable to engage in satisfying activity ". It is associated with a number of psychosocial and psychopathological problems. The aim of this paper is to test the validity of the Italian version of the Multidimendional State Boredom Scale (MSBS). The results of this investigation indicate that the Italian MSBS has factor structure that is similar to the original MSBS. Furthermore, there is evidence that the Italian MSBS has strong reliability. Method: In total, 690 undergraduate students participated in this research. Participants were 51.3% male, and 48.7% female, with a mean age of 24 years (SD = 4.92, range: 18-50 years). Two studies were conducted. In the first study, a confirmatory factor analysis was performed to determine whether data from the Italian MSBS fit the original MSBS factor structure. In the second study, the association between the Italian version of the MSBS and several related measures was examined. These related measures are: The Boredom Proneness Scale; The Dissociative Experiences Scale-II; Beck Depression Inventory-II; Beck Anxiety Inventory; The Eysenck Personality Questionnaire-Short Version; The Behavioural Inhibition System and Behavioural Activation System. Results: Study 1 found that the Italian translation of the MSBS, administered in an Italian-speaking sample, yielded the same factor structure as the original MSBS. Study 2 found that the Italian MSBS demonstrated construct validity in an Italian sample. Conclusions: The results of the present paper demonstrate that the Italian version of the MSBS is both valid and reliable. Study 1 found that the Italian MSBS has a similar factor structure to the original English MSBS, that the Italian MSBS's factors are significantly associated with one another, and that the Italian MSBS has good reliability. Study 2 demonstrated that the MSBS is valid, as it was related to a number of theoretically important constructs.

Reliability centered maintenance (RCM) has a key role in the quality system of thermal power plants. Electricity production is definitely not only production of a product, but also becomes a customer service. Reliability is the top quality tier of this service. Incorporation in the Integrated energy system means fast transformations of organization on all levels. The reliability of modern generation components basically influences the efficiency and capacity of a power plant as a whole. This paper presents the results of RCM practice on Unit Two of The Thermal Power Plant ″Nikola Tesla -B″, 2x600 MW, Yugoslavia. RCM implementation on current problems during exploitation emphasized problems with the boiler tubing system. The methodological approach included outages analyses, marking of the most significant ones, determination of main causes of damage (determination of the material exhaustion state based on expert analyses), application of adequate remaining life assessment methodology and finally the recommendations. Based on these analyses, certain technical solutions were performed and as a result, the mean time between failures of the plant increased, as well as its reliability. According to cost efficiency, RCM methodology presented the most effective cost-benefit method for reliability upgrade.

The volume is a theoretical and practical manual for thermographic inspections in electrical and industrial field. It contains 230 pages of theory and practical informations about guidelines, criteria, applications in electrical and industrial surveys.
In the early chapters the book provides the physical basis of thermography, the technical characteristics of the cameras and their meanings, and the basic measurement techniques (emissivity, reflected ambient temperature, transimissivity).
We then move on to the examination of the main applications in the electrical and industrial, where thermography is covering an increasingly important as a technique of predictive maintenance. Through it possible investigations into the electrical connections, phase imbalances, overloads, loss of isolation and physical damage to the conductors, the normal plants in the low voltage transformer substations.
Are also possible investigations on electric motors, where you can find not only the loss of insulation in the windings but also imbalances and other mechanical problems.
Other applications, of growing interesting, concern photovoltaic systems and data centers.
In other industries we examine the applications in the chemical and petrochemical industries, and in general in industrial process control.
The book contains many pictures of real cases and references to foreign technical standards, with criteria for classifying the severity of thermal anomalies and mathematical examples of application: in the US thermography technique has been recognized as valid by the NFPA (National Fire Protection Agency) for preventing fires of electrical origin, and the major insurance companies promote the application of thermography surveys.
Other chapter covers miscellaneous applications such detecting corrosion under insulation, faults in steam traps, measuring furnace tubes, gas leak detection, refractory damage, checking level in vessels, temperature control in moulds, inspecting fiberglass and wooden boats for osmosis and humidity.

This work tackles the problem of whether the dissociation between two performances in a single-case study should be computed as the difference between the raw or between the standardized (e.g. z) scores. A wrong choice can lead to serious inflation of the probability of finding false dissociations and missing true dissociations. Two common misconceptions are that (i) standardized scores are a universally valid choice, or (ii) raw scores can be subtracted when the two performances concern the same "task/test", otherwise standardized scores are better. These and other rules are shown to fail in specific cases and a solution is proposed in terms of in-depth analysis of the meaning of each score. The scores that should be subtracted are those that better reflect "deficit severities"the latent, unobservable degrees of damage to the cognitive systems that are being compared. Thus explicit theoretical modelling of the investigated cognitive function(s)-the "scenario"-is required. A flowchart is provided that guides such analysis, and shows how a given neuropsychological scenario leads to the selection of an appropriate statistical method for detecting dissociations, introducing the critical concept of "deficit equivalence criterion"-the definition of what exactly a non-dissociation should look like. One further, overlooked problem concerning standardized scores in general (as measures of effect size, of which neuropsychological dissociations are just one example) is that they cannot be meaningfully compared if they have different reliabilities. In conclusion, when studying dissociations, increases in false-positive and false-negative risks are likely to occur when no explicit neuropsychological theory is offered that justifies the definition of what are to be considered as equivalent deficit severities in both performances, and which would lead to appropriate selection of raw, standardized, or any other type of score. More generally, the choice of any measure in any research context needs explicit theoretical modelling, without which statistical risks cannot be controlled.

The impact of economic recession on the education system of Nigeria at the tertiary level was examined in this study. The study is a descriptive survey research. It was carried out in two universities, two polytechnics and one college of education. Three research questions guided the study. A sample of 304 male and female participants responds to the fifteen item questionnaire which yielded the necessary data. Quantitative data were analysed using descriptive statistics, percentages and charts while qualitative data were recorded and discussed. The findings of the study show that economic recession have affected the system of education in Nigeria in various forms. Based on the findings, recommendations were made on the need to improve education system in Nigeria.

Se realiza una revisión de la consistencia interna reportados para la adaptación y estandarización peruana de la versión aplicable a niños y adolescentes del Inventario de Inteligencia Emocional de Bar-On, EQ-i: YV. Esta revisión aborda específicamente los datos publicados por Ugarriza y Pajares
(2004, 2005) sobre el coeficiente α de Cronbach y la homogeneidad de los puntajes de las versiones larga y breve del EQ-i: YV. El análisis de estos aspectos, de acuerdo al género y al tipo de colegio (público o privado), muestra que los coeficientes son generalmente bajos, manteniéndose en un nivel satisfactorio el puntaje total. Esta revisión pone en cuestionamiento la utilidad del EQ-i: YV para aplicaciones clínicas y de investigación, dado el alto grado de varianza de error involucrado en los puntajes del EQ-i: YV . Estos resultados ocurrieron en la versión larga y corta, y en los subgrupos
separados por el sexo y el tipo de colegio. Se discute el impacto de estos resultados en la práctica de la evaluación psicológica.

In this research work, the reliability of a locally designed and constructed clap activated switch was determined. The sound of clap is detected by a small condenser microphone. The microphone transduces the sound wave to electrical waves which is further amplified by transistor connected in the common emitter configuration. The amplified output from the transistor is then fed to the Bistable Multivibrator circuit. The part count method which assumes typical operating conditions of part or components complexity, ambient temperature, various electrical stresses, operation mode and environment (called reference conditions) was used for the estimation of the reliability of the Clap Activation Switch. It is observed that the reliability of the Clap Activated Switch constructed locally have an estimated reliability that ranges between 0.99706 for the first year of operation to 0.94299 around the twentieth year of operation. Further work can be done by evaluating the reliability of the device using part stress analysis; this will enable the determination of the reliability under actual operating conditions to be carried out.

It is important to explore score reliability in virtually all studies, because tests are not reliable. The present paper explains the most frequently used reliability estimate, coefficient alpha, so that the coefficient's conceptual underpinnings will be understood. Researchers need to understand score reliability because of the possible impact reliability has on the interpretation of research results. There are several common misconceptions about the basic ideas of score reliability. Misconceptions are formed due to lack of understanding of the concept of reliability and through careless speech involving statistical jargon. This paper addresses common misconceptions so that later discussions over score reliability will not be hindered. Misconceptions have caused some authors to devalue the reporting of reliability estimates in published research, while others report reliability coefficients inappropriately. A better understanding of score reliability can resolve these misconceptions and enable authors to use reliability coefficients appropriately in literature and speech. A background of the basic ideas of score reliability is introduced and concludes with an explanation of the most frequently used reliability estimate, coefficient alpha, so that the coefficient's conceptual underpinnings will be understood.

Research in work performance involving employees from different types of jobs is needed. Therefore, there is a necessity of generic instrument in work performance. However, most instruments measuring individual work performance are only developed for specific purposes in particular jobs. Thus it is not appropriate to utilize in a research involving workers from different types of jobs. One of generic instruments measuring work performance is Individual work performance questionnaire (IWPQ). The purpose of this research is to do the adaptation process of IWPQ into Indonesian. The procedure in the adaptation process consists of forward translation, synthesis, back translation, back translation review, and cognitive debriefing. Content validity test using Aiken's V shows that all IWPQ items have high Aiken's V. The field test involving 231 employees shows that IWPQ has a good discriminant indexes, ranging from .447 to .734. The Indonesian version of IWPQ also has a good reliability, in task performance (TP) .871; contextual performance (CP) .858; and counterproductive work behavior (CWB) .814.

BACKGROUND: Fishbone diagrams have been widely promoted as a systems-focused hazard analysis tool for use in root cause analysis, but they suffer from a number of structural weaknesses, including a unidirectional structure that only takes into account forces that promote an accident (ignoring those that make the accident less likely or less severe) and a means of displaying these forces that does not convey any difference in strength of influence. In a separate but related issue, many healthcare organizations suffer from a lack of change management expertise.

PROPOSED SOLUTION: To address these concerns, I present a novel technique, the Lovebug diagram, which draws from both Fishbone diagrams and force-field analysis (an approach to analyzing planned change). This new technique adds value to both its progenitor methods, while retaining their key strengths and ease of use. It can be used both prospectively, to assess planned changes, and retrospectively to assess unplanned (accidental) departures from the status quo.

DISCUSSION: The Lovebug diagram is a more powerful analytical tool than its progenitor methods; however, overall adoption of systems-focused tools for root cause analysis remains suboptimal. Additional research is needed to determine how best to promote a truly systems-focused approach to healthcare root cause analysis. Beyond this retrospective use of the technique, it represents a simple tool to assist healthcare organizations with prospective change management.

Available from: http://cri.sagepub.com/content/early/2013/10/25/1356262213510855.abstract

Maintenance Planning and Scheduling is the heart of the maintenance organization - improve it and you improve your maintenance organization. Proactive maintenance strategy  (PMS) is totally dependent on maintenance planning and scheduling (MPS). PMS increases safety, reliability and economics throughput of the plant. It is common knowledge MPS excellence is able to reduce your warehouse inventory, optimize your maintenance strategy, reduce safety health and environmental incidents and increase the entire organization's bottom line more than equivalent sales efforts. traditional maintenance planning and scheduling has failed to achieve this goal, hence this paper. There are five key and innovative learning objectives that this work will provide: (i) How to select the  degree of job plan depending on its complexity (ii) How to apply the popular lean tool "Prioritization Matrix" to work selection. (iii) How to apply the maintenance planners' structured thought flow in a job plan. (iv) How the maintenance organizational structure impacts the maintenance planning and scheduling function. (v) Understanding the maintenance planning process map using typical industry cases.

The aim of this study is to develop a valid and reliable scale for assessing students' achievement in English classes on Simple Past Tense. Firstly, to ensure the content validity expert views were taken into consideration at every stage of the study. Experts were composed of nine English teachers and four curriculum instructors. Secondly, 130 questions were gathered from nine English teachers. 55 questions, which were thought to be testing the same goal, were eliminated and 75 questions were left for pilot study after the opinions of experts. A Pilot study was conducted with 75 questions and 266 students who are in 12 th grade. The students were chosen from four different high schools. The final form of the test consisted of 25 questions. After the application, the data were analyzed with ITEMAN and SPSS. The analysis revealed reliability coefficient (Cronbach Alpha) as 0.81, mean difficulty as 0.54, mean discrimination as 0.36, Spearman Brown Correlation as 0.89. Item total correlation ranged from 0.38 to 0.63. Based on the data obtained, the Simple Past Tense Achievement Test (SPTAT) can be said to be reliable and valid tool to assess students' achievement in English classes on Simple Past Tense.

Sound transmission loss (STL) tests of acoustic insulation panels are commonly performed in large reverberation rooms. Large size rooms are required by acoustic standards to ensure that a large number of modes can be excited in the frequency range of interest, to create a diffuse sound field. However for STL measurements in low frequency range small enclosures should be able to provide adequate homogenous sound fields, namely`pressure sound fields'. The expected effect of the air sealed in an enclosure backing a panel, is to increase the stiffness of the panel artificially raising the first natural frequency of the panel, which corresponds to a minimum value in the STL spectrum. In this paper the influence of the air cavity's added stiffness on the panel STL is investigated in detail. As expected the effect of the sealed air is to increase the plate stiffness and as a result to increase the frequency of its first natural mode, however the effect on the STL in this frequency region is unexpectedly insignificant which removes the need for correcting STL measurements using small enclosures in low frequency range-around their first natural frequency of the panels. 1. INTRODUCTION The effect on the vibration and the STL of flexible panels backed by air enclosures has been investigated extensively by many researchers. Dowell and Voss [1] established that the first panel natural frequency increases as the size of the enclosure is reduced due to the stiffening effect of the air in the enclosure. The second panel mode is affected by the mass loading of the air which reduces its natural frequency. Lyon [2] identifies three frequency ranges for the Noise Reduction (NR) of panels where the thickness and material of the panel and the box depth is such as the panel's first natural frequency is below the first natural frequency of the air cavity. In the lowest frequency range where the panel size is much smaller than the excitation wave length, the sound pressure is considered uniform regardless of the incident angle and the air in the box is modelled as a simple spring adding its stiffness to the bending stiffness of the panel. His model is based on equating the volume displacement of the air cavity and the panel. The result is a NR independent of the frequency of excitation in this frequency range. For the middle frequency range dominated by the first panel resonance and a several higher panel modes a formula is developed for calculating the envelope of the minimum NR. For shallow cavities backing relatively flexible panels Pretlove [3, 4] concludes that calculations of the first mode natural frequency and modal shape are inaccurate without including the coupling effect of higher panel modes. For cases where the

Failures of any of the components that make up the electrical power system always results in outage of electrical power supply. Since consumers served are usually affected, the costs of such outage are enormous ranging from customers dissatisfaction, loss of customers' goodwill and loss of revenue etc. Reliability assessment of these components is required to know exactly why they fail and to determine under what conditions they should be operated for optimum performance. This is usually difficult without assessing their past performance. This paper seeks to analyze the reliability of power transformers-one of the major components in electric power systems-at the Oshogbo Area Control Center in Nigeria for a period of five years (2009-2013). The daily record of transformers' outages on the 330/132 kV and 132/33 kV transformers were obtained. Several indices were determined in order to evaluate the reliability of these transformers. The number and duration of transformers outages were investigated and analyzed, the MTTF for 132/33 kV transformers is 1.77 years and the failure rate is 0.5650 per year while the MTTF for 330/132 kV transformers is 2.30 years and the failure rate is 0.4348 per year.

Este artículo presenta los resultados del análisis de la fiabilidad interna de un cuestionario que ha sido construido para evaluar la presencia de los procesos matemáticos en las prácticas de enseñanza-aprendizaje de las matemáticas. Una vez validado el instrumento mediante juicio de expertos en un estudio previo, 20 expertos evaluadores administran el instrumento a 95 maestros de colegios de Educación Infantil y Primaria de la Comunidad de Murcia (España). Los datos obtenidos han sido analizados con el paquete estadístico R versión 3.1.0 sobre una plataforma i686-pc-linux-gnu (32-bit). El coeficiente alfa de Cronbach, basado en puntuaciones estandarizadas, muestra que la consistencia interna es buena (coeficiente alfa medio .789 en Infantil y .86 en Primaria), siendo el valor más bajo el correspondiente al proceso “representación” en Educación Infantil, con un valor de .74, que puede valorarse también como una consistencia interna aceptable.

This article presents the results of an internal reliability analysis of a questionnaire designed to evaluate the presence of mathematical processes in the practices used to teach and learn mathematics. After validating the instrument by means of expert judgement in a prior study, 20 expert evaluators administered the instrument to 95 teachers of preschool and primary education in the Community of Murcia (Spain). The data obtained has been analysed with the R-3.1.0 statistical package on an i686-pc-linux-gnu (32-bit) platform. Based on standardised scores, the Cronbach alpha shows a good level of internal consistency (median alpha coefficient .789 for Preschool and .86 for Primary), with the lowest level corresponding to the process of “representation” in preschool, with a value of .74, which is still considered to be an acceptable level of internal consistency.

Consultation is an important feature of research and, increasingly, researchers are required to work in partnership with stakeholders to increase the impact of their work. Our aim is to demonstrate what can be learned from the scholarship on, and practice of, member checking to facilitate productive knowledge exchange. Using dialogical analysis we explore three member check interactions from three different qualitative psychology projects focusing our analysis on difficult moments between researchers and participants conceptualised here as ‘sore spots’. We identify two major genres in these sequences: participant ambivalence and participant challenge. We then consider passages that allow us to explore a more theoretical understanding of these two genres in terms of the metaphor of portraits and mirrors. Overall, we outline how implicit epistemologies and theories of subjectivity (uncomplicated, blank, and complex) may be linked to the way in which stakeholders approach research. We also provide a map with regard to the theories within which member checks can be undertaken, associated research practices in terms of a range of researcher responses to stakeholder ambivalence and challenge, and implications of these moments for knowledge exchange for qualitative research but also for psychological science as a whole. We conclude that sore spots in knowledge exchange process can be productive opportunities of transformational validity.

Keywords: member check; knowledge exchange; research impact; dialogical analysis; participant validation

The paper shows how error statistical theory can be deployed to grasp the deeper epistemic logic of the peer-review process. The intent is to provide the readers with a novel lens through which to make sense of the practices of academic publishing.

Sazetak: Pouzdanost sobraćajnog sistema se definiše kao njegova sposobnost da uspešno obavlja zadate mu funkcije i održava vrednost eksploatacionih parametara, u propisanim i zadatim granicama pod određenim uslovima i u datom vremenskom intervalu. U radu je prikazan razvoj dva softverska sistema za analizu pouzdanosti komponenti tehničkih sistema, i to: RATSC-CTD (softverski sistem za analizu pouzdanosti komponenti tehničkih sistema na osnovu izbora teorijske raspodele prema karakteristikama teorijskih raspodela, kojom se najbolje aproksimiraju eksperimentalni podaci) i RATSC-CA (softverski sistem za analizu pouzdanosti komponenti tehničkih sistema na osnovu izbora teorijske raspodele zasnovano na komparativnoj analizi, kojom se najbolje aproksimiraju eksperimentalni podaci), koji su razvijeni i pisani u FORTRAN i C++ programskim jezicima od strane autora ovog rada. Korišćenjem razvijenih softverskih sistema prikazani su primeri analize pouzdanosti komponenti sobraćajnih sistema.
Ključne reči: pouzdanost, analiza pouzdanosti, softverski sistem, saobraćajni sistem.
Abstract: The reliability of the traffic system is defined as its ability to successfully perform its functions and maintain the value of the exploitation parameters, within the prescribed and defined limits under certain conditions and within a given time interval. The paper presents the development of two software systems for reliability analysis of technical system components, as follows: RATSC-CTD (Software system for Reliability Analysis of Technical System Components on the Basis of Choice of Theoretical Distribution According to Characteristics of Theoretical Distributions, which in the best way Approximate Experimental Data) and RATSC-CA (Software system for Reliability Analysis of Technical System Components on the Basis of Choice of Theoretical Distribution Based on Comparative Analysis, which in the best way Approximate Experimental Data), which have been developed and written in FORTRAN and C++ programming languages by the authors of this paper. Using the developed software systems, examples of the reliability analysis of the component system components are presented.
Keywords: reliability, reliability analysis, software system, traffic system.

How to cite this article: Dašić, P.: Razvoj softverskih sistema za analizu i modeliranje pouzdanosti komponenti saobraćajnih sistema. Zbornik radova Internacionalnog univerziteta Travnik / Proceedings of the International University of Travnik, God. 7, br. 17 (2018), str. 115-130. ISSN 2232-8807.

This study examined the reliability and validity of an instrument, which is proposed to measure an extended Unified Theory of Acceptance and Use of Technology (UTAUT) model. The extended model has a total of six exogenous variables namely; Performance Expectancy, Effort Expectancy, Social Influence, Facilitating Conditions and Customer Concerns and one endogenous variable; Behavioural Intention. 37 items that measure the variables are adapted from extant literature, thus modified to suit the Nigerian retail context. Therefore the instrument required a series of validity and reliability assessment to ensure completeness and clarity of the measures. Thus the items were subjected to face validity and factor analysis. We modified the adapted items, designed the questionnaire, and conducted the face validity. 26 valid data were gathered in a pilot survey, from owners/managers of retail businesses in Nigeria. The data were analysed using SmartPLS 2.0 software. Result of Partial Least Square – Structural Equation Modeling (PLS-SEM) measurement model indicated a good validity and reliability of the measures. All the values for Average Variance Extracted (AVE), Composite Reliability, Discriminant and Convergent Validity and Factor Loadings met and exceeded the minimum threshold; therefore the current measures are retained for a full-scale study of the extended model.

The coefficient alpha is the most widely used measure of internal consistency for composite scores in the educational and psychological studies. However, due to the difficulties of data gathering in psychometric studies, the minimum sample size for the sample coefficient alpha has been frequently debated. There are various suggested minimum sample sizes for the robust estimate of the population coefficient alpha. This research indicates that the performance of an estimator of the coefficient alpha depends not only on the sample size but also on the largest eigenvalue of the sample data set. Thus, when the largest eigenvalue increases, unbiased estimation of the population coefficient alpha is possible, even though the sample size is small. The simulations in this study were based on Monte-Carlo method with bootstrap technique.

La teoría de demandas y recursos laborales (Bakker & Demerouti, 2007) constituye en la actualidad un paradigma de gran importancia para explicar los procesos de motivación y salud ocupacional. En el presente estudio instrumental, se analizan las propiedades psicométricas de tres escalas validadas previamente en una muestra de estudiantes universitarios. Dichas escalas evalúan recursos personales generales, derivados de la teoría social cognitiva, relevantes al ámbito laboral: Escala de Apoyo Social Percibido, Escala de Expectativas de Resultados y Escala de Progreso en Metas. Para llevar a cabo la investigación, se conformó una muestra de 223 trabajadores argentinos. Se efectuaron análisis de validez de constructo y de criterio. Asimismo, la confiabilidad fue evaluada por medio de los coeficientes alfa y omega. Los resultados obtenidos apoyan la unidimensionalidad de las escalas, las relaciones teóricamente relevantes con las dimensiones del burnout, engagement, emociones positivas y satisfacción laboral, así como los indicadores de confiabilidad apropiados. Se discuten las implicancias prácticas de los hallazgos.

Reliability quantification is a critical and necessary process for the evaluation and assessment of any inspection technology that may be classified either as a Nondestructive Evaluation (NDE) or Structural Health Monitoring (SHM) technique. Based on the sensitivity characterization of NDE techniques, appropriate processes have been developed and established for the reliability quantification of their performance with respect to damage/flaw detection in materials or structures. However, in the case of SHM-based methods, no such well-defined and general applicable approaches have been established for neither active nor passive sensing techniques that allow for their accurate reliability quantification.

The objective of this study is to characterize the sensitivity of active sensing acousto- ultrasound-based SHM techniques with respect to damage detection, as well as to identify the parameters that influence their sensitivity. With such an understanding, it is believed that adequate quantitative methods could then be established to enable the practical use of acousto- ultrasound SHM methods in the aerospace and mechanical engineering communities.

In order to evaluate the sensitivity of a pre-selected active sensing acousto-ultrasound SHM system, both numerical simulations and experiments were performed on thirty aluminum coupons each outfitted with a pair of Lead-Zirconate-Titanate (PZT) based piezoelectric sensors/actuators. A damage index versus damage size relationship was investigated numerically and experimentally to assess the applicability of the traditional NDE linear regression framework for Probability of Detection (POD) for an active sensing SHM system. The results of the study show that the position of each sensor-actuator pair with respect to a known damage location and the damage growth pattern are the two most critical parameters influencing the reliability of the same SHM system applied to identical structural components under the same environmental conditions.

A growing public awareness of the potential negative impacts of corporate activities on the natural environment and society compels large companies to invest increasing resources in the communication of their responsible conduct. This article employs Appraisal theory in a comparative analysis of BP’s and IKEA’s 2009 social reports, each company’s record of their non- financial performance. The main objective is to explore how, through Appraisal resources, BP and IKEA construct their corporate identity and relationship with their stakeholders. The analysis reveals two markedly different approaches to the construction of a responsible corporate identity. While BP deploys interpersonal resources to portray itself as a trustworthy and authoritative expert, IKEA discloses itself as a sensitive and caring corporation, engaged in a continual effort to improve. These differences are interpreted in light of the legitimization challenges the two companies face.

Pembuatan soal menjadi hal wajib yang harus dilakukaan oleh seorang pendidik untuk mengetahui tingkat pencapaian kompetensi peserta didik. Banyak hal yang harus diperhatikan dalam pembuatan soal agar soal dapat dikatakan baik. Ada beberapa kriteria tes yang berkualitas, yaitu valid, relevan, spesifik, representatif, seimbang, sensitif, fair, dan praktis. Sehingga penguasaan pembuatan instrumen tes harus dimiliki oleh setiap pendidik untuk menghasilkan soal-soal yang berkualitas sehingga dapat mengukur kemampuan peserat didik dengan baik secara objektif
Dalam penelitian ini, penulis mencoba membuat instrument dimulai dengan pembuatan kisi-kisi yang disesuaikan dengan KI dan KD, uji coba sampai pada analisis hasil uji coba. Pada uji coba ke lapangan, mata pelajaran yang diujikan yaitu Pendidikan Agama Islam. Penelitiannya dilaksanakan di SD Ashfiya Kota Bandung dengan mengambil sampel sebanyak 20 orang. Adapun untuk mengetahui sejauh mana kualitas soal yang diujikan maka perlu adanya analisis lebih lanjut yang akan dijelaskan dalam laporan ini.

The coefficient alpha is the most widely used measure of internal consistency for composite scores in the educational and psychological studies. However, due to the difficulties of data gathering in psychometric studies, the minimum sample size for the sample coefficient alpha has been frequently debated. There are various suggested minimum sample sizes for the robust estimate of the population coefficient alpha. This research indicates that the performance of an estimator of the coefficient alpha depends not only on the sample size but also on the largest eigenvalue of the sample data set. Thus, when the largest eigenvalue increases, unbiased estimation of the population coefficient alpha is possible, even though the sample size is small. The simulations in this study were based on Monte-Carlo method with bootstrap technique. OZET: Egitimsel ve psikolojik calismalarda birlesik olcmelerin guvenirliginin hesaplamasinda yaygin olarak Cronbach (1951) tarafindan gelistirilen alfa katsay...

As technology continues to advance, the need to create benchmark or standards for systems becomes a necessity so as to ensure that these new advanced systems functions at its maximum capacity over a long period of time without any failure, fault or errors occurring. The internet of things technology promises a broad range of exciting products and services, with car tracking technology as part of the broad range of technological concept under the internet of things paradigm. The car tracking technology involves deploying some basic internet of things components into the tracking of important transportation component; the basic principle behind any technological concept involves delivery of high quality product that conforms to specifications. In this paper, the concept and technological description about the internet of things is discussed with emphasis on the principal functional component, this is to enable a broaden conceptualization about car tracking technology because it needs to function correctly, at all time. The concept of reliability engineering is also discussed in respect to an important quality factor, which entails that systems must function correctly without fault, failure or errors, it provides benchmark, principles, or standards in which the internet of things system must possess for an increased quality assurance.

A National Aeronautics and Space Administration (NASA) supported Reliability, Maintainability, and Availability (RMA) analysis team developed a RMA analysis me thodology that uses cut set and importance measure analyses to compare model proposed avionics computing architectures. In this paper we will present an effective and efficient application of the RMA analysis methodology for importance measures that includes Reliability Block Diagram (RBD) Analysis, Comparison modeling, Cut Set Analysis, and Importance Measure Analysis. In addition, we will also demonstrate that integrating RMA early in the system design process is a key and fundamental decision metric that supports design selection. The RMA analysis methodology presented in this paper and applied to the avionics architectures enhances the usual way of predicting the need for redundancy based on failure rat es or subject matter expert opinion. Typically, RBDs and minimal cut sets along with the Fussell-Vesely (FV) method is used to calculate importance measures are calculated for each functional element in the architecture [1]. This paper presents an application of the FV importance measures and presents it as a methodology for using importance measures in success space to compare architectures. These importance measures are used to identify which functional element is most likely to cause a system failure, thus, quickly identifying the path to increase the overall system reliability by either procuring more reliable functional elements or adding redundancy [2]. This methodology that used RBD analysis, cut set analysis, and the FV importance measures allowed the avionics design team to better understand and compare the vulnerabilities in each scenario of the architectures. It also enabled the design team to address the deficiencies in the design architectures more efficiently, while balancing the need to design for optimum weight and space allocations.