DIVERSITY AND KNOWLEDGE SHARING IN CONSTRUCTION: A MATHEMATICAL MODEL

Author(s):  
Daoud Kiomjian ◽  
F. Jordan Srour ◽  
Issam Srour

Conventional wisdom in the management literature holds that diversity is positively correlated with performance. Yet, the findings from the construction field indicate that this is not always the case. In an effort to study the interaction between diversity and performance in the construction industry, this paper presents the elements of a theoretical mathematical model to explore the relationship between diversity and knowledge sharing which is a precursor of performance. This model includes five dimensions of diversity: ethnicity, age, experience, language and education. At the heart of the mathematical model is a fuzzy based system that generates the probability of knowledge sharing among members with different demographic attributes. The presented fuzzy system will, in future work, become the foundation of an agent based model used to study the impact of worker interactions on productivity.

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3390
Author(s):  
Željko Knezić ◽  
Željko Penava ◽  
Diana Šimić Penava ◽  
Dubravko Rogale

Electrically conductive yarns (ECYs) are gaining increasing applications in woven textile materials, especially in woven sensors suitable for incorporation into clothing. In this paper, the effect of the yarn count of ECYs woven into fabric on values of electrical resistance is analyzed. We also observe how the direction of action of elongation force, considering the position of the woven ECY, effects the change in the electrical resistance of the electrically conductive fabric. The measurements were performed on nine different samples of fabric in a plain weave, into which were woven ECYs with three different yarn counts and three different directions. Relationship curves between values of elongation forces and elongation to break, as well as relationship curves between values of electrical resistance of fabrics with ECYs and elongation, were experimentally obtained. An analytical mathematical model was also established, and analysis was conducted, which determined the models of function of connection between force and elongation, and between electrical resistance and elongation. The connection between the measurement results and the mathematical model was confirmed. The connection between the mathematical model and the experimental results enables the design of ECY properties in woven materials, especially textile force and elongation sensors.


2015 ◽  
Vol 778 ◽  
pp. 259-263
Author(s):  
Fa Jun Zhang ◽  
Lin Zi Li ◽  
Hui Lin ◽  
Yin Lin Pu ◽  
Zhu Xin

Various uncertain factors affect the movement of the welding robot, thus welding gun tend to deviate from the theory of welding position which reduces the welding accuracy, of which the revolute pair clearance have an greater effect on the movement of the welding robot. In order to study the influence of revolute pair clearance to the end pose accuracy of welding robot, the mathematical model of revolute pair clearance was established, and the software SolidWorks was used for establishing the welding robot model, making simulations of the mechanical arm with joint clearance and no joint clearance. At last, the movement characteristic of the hinge shaft is attained. The simulation results showed that the shaft velocity and displacement of mechanical arm with joint clearance has a certain degree of fluctuation, which affecting the end pose accuracy of welding robot , and reducing the movement stability and the welding accuracy of welding robot.


Author(s):  
Hamdy Hassan

Abstract In this paper, a theoretical study is presented on enhancement of the solar still performance by using the exhaust gases passing inside a chimney under the still basin. The impact of the exhaust gases temperature on the solar still temperature, productivity, and efficiency are considered. The performance of solar still with chimney is compared with that of conventional solar still. The study is carried out under the hot and climate conditions of Upper Egypt. A complete transient mathematical model of the physical model including the solar still regions temperatures, productivity, and heat transfer between the solar still and the exhaust gases are constructed. The mathematical model is solved numerically by using fourth-order Runge-Kutta method and is programmed by using MATLAB. The mathematical model is validated using an experimental work. The results show that the solar still saline water temperature increases and productivity with using and rising the exhaust gases. Furthermore, the impact of using exhaust gases on the still performance in winter is greater than in summer. using chimney exhaust gases at 75 °C and 125 °C enhances the daily freshwater yield of the conventional still by more than three times and about six times in winter, respectively, and about two and half times and more than three times in summer, respectively.


2018 ◽  
Vol 30 (8) ◽  
pp. 592-612 ◽  
Author(s):  
Amro Alzghoul ◽  
Hamzah Elrehail ◽  
Okechukwu Lawrence Emeagwali ◽  
Mohammad K. AlShboul

Purpose This study aims at providing empirical evidence pertaining to the interaction among authentic leadership, workplace harmony, worker's creativity and performance in the context of telecommunication sector. These research streams remain important issues and of interest as the world continues to migrate toward a knowledge-based economy. Design/methodology/approach Applying structural equation modeling, this study diagnosed the impact of Authentic leadership (AL) on employees (n = 345) in two Jordanian telecommunication firms, specifically, how it shapes workplace climate, creativity and job performance. The study also tests the moderating role of knowledge sharing in the model, as well as the mediating role of workplace climate on the relationship between AL and positive organizational outcomes. Findings The empirical result suggests that AL positively influences workplace climate, creativity and job performance; workplace climate positively influences creativity and job performance; workplace climate mediates the relationship between AL and creativity, and job performance; and knowledge sharing behavior moderates the relationship between AL and workplace climate. Originality/value This study highlights the magnificent power of AL and knowledge sharing, not only in shaping the workplace atmosphere but also in delineating how these variables stimulate creativity and performance among employees. The implications for research and practice are discussed.


2020 ◽  
pp. 442-451
Author(s):  
А.V. Batig ◽  
A. Ya. Kuzyshyn

One of the most important problems that pose a serious threat to the functioning of railways is the problem of freight cars derailment. However, according to statistics, the number of cases of the derailments of freight cars in trains annually grows. Тo prevent such cases, the necessary preventive measures are developed, and to study the causes of their occurrence, a significant number of mathematical models, programs and software systems created by leading domestic and foreign scientists. Studies of such mathematical models by the authors of this work have led to the conclusion that they are not sufficiently detailed to the extent that it is necessary for analyze the reasons of its derailment. At the same time, an analysis of the causes of the rolling stock derailments on the railways of Ukraine over the past five years showed that in about 20 % of cases they are obvious, and in 7 % of cases they are not obvious and implicitly expressed. The study of such cases of rolling stock derailment during an official investigation by the railway and during forensic railway transport expertises requires the use of an improved mathematical model of a freight car, which would allow a quantitative assessment of the impact of its parameters and rail track on the conditions of railway accidents. Therefore, taking into account the main reasons that caused the occurrence of such railroad accidents over the last five years on the railways of Ukraine, the article selected the main directions for improving the mathematical model of a freight car, allowing to cover all the many factors (explicit and hidden) and identify the most significant ones regarding the circumstances of the derailment rolling stock off the track, established on the basis of a computer experiment. It is proposed in the mathematical model of a freight car to take into account the guiding force, the value of which is one of the main indicators of the stability of the rolling stock. The authors of the article noted that not taking into account the influence of the guiding forces on the dynamics of the freight car can lead to an erroneous determination of the reasons for the rolling stock derailment or even to the impossibility of establishing them.


2013 ◽  
Vol 572 ◽  
pp. 636-639
Author(s):  
Xi Chen ◽  
Gang Wang

This paper deals with the walking stability analysis of a multi-legged crablike robot over slope using normalized energy stability margin (NESM) method in order to develop a common stabilization description method and achieve robust locomotion for the robot over rough terrains. The robot is simplified with its static stability being described by NESM. The mathematical model of static stability margin is built so as to carry out the simulation of walking stability over slope for the crablike robot that walks in double tetrapod gait. As a consequence, the relationship between stability margin and the height of the robots centroid, as well as its inclination relative to the ground is calculated by the stability criterion. The success and performance of the stability criterion proposed is verified through MATLAB simulation and real-world experiments using multi-legged crablike robot.


E-Management ◽  
2021 ◽  
Vol 4 (3) ◽  
pp. 50-60
Author(s):  
M. V. Samosudov

The formation and formation of the Industry 4.0 concept stimulated the discussion of the use of computer technology in various areas of economic activity and, in particular, in the automation of social systems management. The basis of the concept is the inclusion of a virtual image of the social system in the form of a mathematical model or a digital twin of the enterprise in the production and management system. At the same time, it should be noted that today digital twin are created mainly only for technical objects used in the activities of enterprises. The purpose of the article is to demonstrate the possibility of fixing organizational documents as one of the system-forming factors in the digital twin of an enterprise. This circumstance makes it possible, firstly, to more accurately calculate the managerial effects of managers by taking into account the impact of organizational documents on the activities of employees of the enterprise; secondly, to identify conflicts of documents developed by various departments of the company; thirdly, to calculate the content of documents during their development (design), based on the requirements of the situation or a given control effect. This possibility arises due to the use of a comprehensive mathematical model of the social system operating in an active environment. The model is a simulation agent-based model and allows you to calculate the dynamics of the social system in the socio-economic space, which allows its use in decision support systems by managers of any scale and activities to calculate the expected effect of management decisions – the specifics of a particular social system are taken into account by combining the values of the phase variables describing the state of the enterprise. The novelty of the research paper lies in the fact that it shows: the possibility to calculate the influence of organizational documents on the behavior of participants and, consequently, on the result of the social system, as well as the mechanism for converting messages, which are invariants of socio-economic space into information that affects the behavior of participants of relations.


Author(s):  
Cheng Zhu ◽  
Tian Yu ◽  
Qing Chang ◽  
Jorge Arinez

Abstract In a multistage serial production line, products with defect can be repaired or reworked to ensure high product quality. This paper studies a multistage serial manufacturing system with quality rework loops. Rework is the activity to repair or repeat the work on the defect parts during manufacturing processes, and it adds to cost and cycle time. This paper introduces an event-based data-enabled mathematical model for a stochastic production line with quality rework loops. The system performance properties are analyzed and permanent production loss due to quality rework loops is identified. The mathematical model and system performance identification methodology are studied analytically through numerical case studies.


2021 ◽  
Vol 5 (2) ◽  
Author(s):  
Ibrahim A Abuashe ◽  
Bashir H Arebi ◽  
Essaied M Shuia

A mathematical model based on the momentum, continuity and energy balance equations was developed to simulate the behavior of the air flow inside the solar chimney system. The model can estimate the power output and performance of solar chimney systems. The developed mathematical model is validated by the experimental data that were collected from small pilot solar chimney; (experiment was presented in part I). Good agreement was obtained between the experimental results and that from the mathematical model. The model can be used to analyze the solar chimney systems and to determine the effect of geometrical parameters such as chimney height and collector diameter on the power output and the efficiency of the system


Author(s):  
Kelli L Sullivan ◽  
Paulina A Kulesz ◽  
Steven Paul Woods

Abstract Objective Retrospective and prospective memory deficits are associated with lower quality of life (QoL); however, there are no validated measures that comprehensively and directly assess the impact of memory problems on QoL. The Survey of Memory-Related Quality of Life (SMRQoL) was developed as a 30-item questionnaire to measure memory-related QoL. Method Both HIV+ (n = 195) and HIV− (n = 146) participants completed the SMRQoL, a neurocognitive research battery, and validated self-report questionnaires of memory, QoL, and mood. Participants were recruited into younger (age ≤ 40 years) and older (age ≥ 50 years) groups per the parent study design. Results The SMRQoL had a unidimensional factor structure and demonstrated measurement invariance across the HIV+ and HIV− participants. Analyses of 111 clinically stable participants (e.g., persons with no incident or remitting central nervous system disorders) who returned for a 14-month follow-up visit indicated that the SMRQoL had adequate test–retest stability. There was a significant interaction of age and HIV status on the SMRQoL, such that older HIV+ participants reported the lowest memory-related QoL. SMRQoL scores were associated with validated measures of mental and physical QoL, self-reported memory and cognitive symptoms, and performance-based memory and executive functions. Conclusions The SMRQoL shows evidence of reliability and validity as a measure of memory-related QoL that can be used to assess the impact of memory problems on everyday life, but future work is needed to demonstrate the measure’s incremental value in the context of diagnosis and treatment.


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