H.S. Ketan, M.A. Al‐Bassam, M.B. Adel and I. Rawabdeh
Concurrent design and manufacturing is widely accepted as essential for obtaining an economically conceivable design solution for industrial production. Nevertheless the…
Abstract
Concurrent design and manufacturing is widely accepted as essential for obtaining an economically conceivable design solution for industrial production. Nevertheless the development of a viable computer‐aided inspection planning (CAIP) using CAD as input for effective NC‐measuring data preparation has not yet been successful. This paper introduces an approach to direct integration between CAD and CAIP by developing a feature‐based computer aided design/inspection planning (FB‐CAIP) system. The FB‐CAIP system contains a computer‐internal model of a product that contains sufficient information to guide the direct generation of NC code of the inspection activity. The developed small prototype system integrates knowledge‐based inspection planning with feature‐based CAD system for an automatic CNC measuring program generation of prismatic parts.
Details
Keywords
S. Sathvik, L. Krishnaraj and Bankole Osita Awuzie
Sleep quality has been associated with health and safety issues influencing construction labour productivity in developing countries. Despite its significantly adverse…
Abstract
Purpose
Sleep quality has been associated with health and safety issues influencing construction labour productivity in developing countries. Despite its significantly adverse contribution to these facets if left unattended to, limited studies have sought to establish its prevalence and causal factors in labour-intensive contexts. This study aims to bridge the gap between the prevalence and casual factors of poor sleep quality among construction workers.
Design/methodology/approach
Adopting a case study research design, data were collected from a randomly selected sample of construction workers (n = 475) recruited from four construction-based corporations in Southern India. Self-administered questionnaires comprising a Pittsburgh Sleep Quality Index (PSQI) scale was used to measure sleep quality among respondents alongside demographic characteristics, lifestyle preferences and work-habits data. Data were analysed using multivariate logistic regression analysis and descriptive statistical techniques.
Findings
Slightly more than a third of the construction workers (n = 33.9%) surveyed experienced poor sleep quality based on a PSQI method score of = 5. Also, the nexus between demographic characteristics, lifestyle preferences and work habits on the incidence of poor sleep quality among construction workers was confirmed.
Practical implications
The study contributes to the contemporary discourse on improving sleep health of construction workers to enhance their well-being thereby enabling their contribution towards achieving improved construction labour productivity.
Originality/value
This study makes an original contribution to the extent that it seeks to not only determine the prevalence of sleep quality within the construction industry and associated causal factors but to explore its implications on construction labour productivity.
Details
Keywords
Osman Ulas Aktas, Lawrence Kryzanowski and Jie Zhang
This paper aims to analyze the impact of price-limit hits by hit type and when such hits start and stop using intraday trades and quotes at a one-second frequency for firms…
Abstract
Purpose
This paper aims to analyze the impact of price-limit hits by hit type and when such hits start and stop using intraday trades and quotes at a one-second frequency for firms included in the BIST-50 index during the 13-months starting with March 2008. Like the recent COVID-19 period, this period includes the heightened stress in global financial markets in September 2008.
Design/methodology/approach
Using intra-day trades and quotes at a one-second frequency, the authors examine the market effects of price limits for firms included in the BIST-50 index during the global financial crisis. The authors compare the values of various metrics for 60 min centered on price-limit hit periods. The authors conduct robustness tests using auto regressive integrated moving average (ARIMA) models with trade-by-trade and with 3-min returns.
Findings
The findings are supportive of the following hypotheses: magnet price effects, greater informational asymmetric effects of market quality and each version of price discovery. Results are robust using samples differentiated by cross-listed status, same-day quotes instead of transaction prices and equidistant and trade-by-trade returns.
Originality/value
The authors use intraday data to reduce measurement error that is particularly pronounced when daily data are used to assess price limits that start and/or stop during a trading session. The authors contribute to the micro-structure literature by using ARIMA models with trade-by-trade and 3-min returns to alleviate some bias due to the autocorrelations in returns around price-limit hits in the presence of a magnet effect. The authors include some recent regulation changes in various countries to illustrate the importance of circuit breakers using price limits during COVID-19.
Details
Keywords
Gulden Gumusburun Ayalp and Ilhami Ay
Prefabricated construction technology enables relatively faster and easier construction of building structures at a lower project cost, providing improved quality control with…
Abstract
Purpose
Prefabricated construction technology enables relatively faster and easier construction of building structures at a lower project cost, providing improved quality control with minimal material waste. Despite the advantages of prefabricated construction systems, they are not extensively used in Turkey because of specific yet largely undefined challenges. Therefore, the purpose of this study aims to determine the factors currently affecting the extensive use of prefabricated construction systems in Turkey.
Design/methodology/approach
The reasons for such systems not being used extensively in Turkey were examined using responses to a questionnaire distributed amongst architects working at design firms, prefabricated-building manufacturers and contractors. The obtained survey data were statistically analysed using the SPSS 22 and LISREL 8.7 software to rank the severity of the identified challenges and determine the most critical factors.
Findings
Eight critical factors groups affecting the use of prefabricated construction systems and their associated factors were identified according the responses provided by the participants. Potential solutions and recommendations were proposed based on these factor groups that are expected facilitate the implementation of prefabricated construction systems in Turkey.
Originality/value
Little previous research has provided insight into the specific factors limiting the use of prefabricated construction systems. This study accordingly approaches the subject considering all phases of prefabricated construction systems and presents a structural model of the factors obtained by a confirmatory factor analysis for application to expand the use of prefabricated construction systems.
Details
Keywords
Jonathan S. Greipel, Regina M. Frank, Meike Huber, Ansgar Steland and Robert H. Schmitt
To ensure product quality within a manufacturing process, inspection processes are indispensable. One task of inspection planning is the selection of inspection characteristics…
Abstract
Purpose
To ensure product quality within a manufacturing process, inspection processes are indispensable. One task of inspection planning is the selection of inspection characteristics. For optimization of costs and benefits, key characteristics can be defined by which the product quality can be checked with sufficient accuracy. The manual selection of key characteristics requires substantial planning effort and becomes uneconomic if many product variants prevail. This paper, therefore, aims to show a method for the efficient determination of key characteristics.
Design/methodology/approach
The authors present a novel Algorithm for the Selection of Key Characteristics (ASKC) based on an auto-encoder and a risk analysis. Given historical measurement data and tolerances, the algorithm clusters characteristics with redundant information and selects key characteristics based on a risk assessment. The authors compare ASKC with the algorithm Principal Feature Analysis (PFA) using artificial and historical measurement data.
Findings
The authors find that ASKC delivers superior results than PFA. Findings show that the algorithms enable the cost-efficient selection of key characteristics while maintaining the informative value of the inspection concerning the quality.
Originality/value
This paper fills an identified gap for simplified inspection planning with the method for the efficient selection of key features via ASKC.
Details
Keywords
Cheng Fan, Deng Binchao and Yilin Yin
Under the background that engineering, procurement and construction (EPC) contracting model is introduced to adapt to the highly fragmented characteristics of prefabricated…
Abstract
Purpose
Under the background that engineering, procurement and construction (EPC) contracting model is introduced to adapt to the highly fragmented characteristics of prefabricated construction, the schedule management of general contractor is faced with the challenge of dynamic transmission and interaction of construction scheduling-related risk. The purpose of this paper is to develop the hierarchy of prefabricated construction scheduling-related risks from the perspective of the general contractor, and to analyze the transmission mechanism between risks. The paper also aims to further distinguish the difference of the impact degree of scheduling-related risks, and provide reference for formulating the strategy to alleviate the construction delay.
Design/methodology/approach
Based on a review of the literature on prefabricated buildings, this paper identifies 22 scheduling-related risks in construction from the perspective of the general contractor. Semi-structured interviews were then conducted to obtain experts' views on the interrelationships among these risks. Following this, their overall structure was determined by using a hierarchical structure established by using interpretive structural modeling (ISM), and Matrice d'Impacts Croisés Multiplication Appliqués à un Classement (MICMAC) technique was applied to classify them into four groups according to their driving and dependence powers.
Findings
The results indicate that the 22 scheduling-related risks in construction followed the inherent path of step-by-step transmission, and all of them could cause different degrees of delays in prefabricated construction. Among them, general experience in contracting projects, the use of emerging technologies and the completeness of the relevant standards and specifications were strong drivers of scheduling delays in construction, and should be prioritized by the general contractor in schedule management. The transitive link between scheduling risks can guide them in developing prevention strategies.
Research limitations/implications
Data quality and reliability risks are the major drawbacks of semi-structured interviews. These were minimized by engaging experts with rich theoretical and hands-on experience in prefabricated construction projects. The hierarchical model only reflects static influence relationships, and so dynamic interactions among scheduling-related risks should be studied in future.
Originality/value
The primary value of this study is in its development of a hierarchical model by using the integrated ISM–MICMAC approach that reflects the interaction between scheduling risks in the construction of prefabricated buildings. The hierarchy of these risks and the results of a “driving-dependence power” analysis can guide the general contractor in taking targeted preventive measures to avoid scheduling delays in the construction of prefabricated buildings.
Details
Keywords
S. Vinodh, G. Sundararaj, S.R. Devadasan, D. Kuttalingam, J. Jayaprakasam and D. Rajanayagam
Agile manufacturing (AM) refers to the capability of an organisation to quickly respond to the customers' dynamic demands. The purpose of this paper is to report a research which…
Abstract
Purpose
Agile manufacturing (AM) refers to the capability of an organisation to quickly respond to the customers' dynamic demands. The purpose of this paper is to report a research which is carried out to explore the interfacing of computer aided design/computer aided manufacturing (CAD/CAM) in a traditional manufacturing company with the purpose of acquiring AM characteristics.
Design/methodology/approach
The CAD model of an existing electronics switch is developed using Pro/E package. Then, the mold adviser package is used to design the existing mold of this component. On studying this mold, ten new models of it are designed using the mold adviser package.
Findings
The new models developed through CAD/CAM interfacing are found to possess more agile characteristics than those possess by the existing mold.
Research limitations/implications
The explorative study is conducted in only one traditional manufacturing company. In this company several world class manufacturing strategies like kaizen and total productive maintenance are implemented. This endeavour mimics those pursue in majority of the companies situated in different parts of the world. This implies that the contributions of this research would be useful to majority of those companies as well.
Practical implications
A roadmap is developed which will be useful for practically applying CAD/CAM interfacing with the objective of implementing AM.
Originality/value
It appears that no researcher has examined the interfacing of CAD/CAM for achieving agility in manufacturing organisations. This paper reports a research, which is conducted to fill this research and practice gap. Hence, this research is original and valuable to both researchers and practitioners.
Details
Keywords
David Kimera and Fillemon Nduvu Nangolo
The purpose of this paper is to review maintenance practices, tools and parameters for marine mechanical systems that can be classified as plant, machinery and equipment (PME). It…
Abstract
Purpose
The purpose of this paper is to review maintenance practices, tools and parameters for marine mechanical systems that can be classified as plant, machinery and equipment (PME). It provides an insight for the maintenance crew on which maintenance parameters and practices are critical for a given PME systems.
Design/methodology/approach
The review paper characterizes the various maintenance parameters and maintenance practices used onshore and offshore for PME and identifies the possible gaps.
Findings
A variety of maintenance techniques are being used in the marine industry such as corrective maintenance, preventive maintenance and condition-based maintenance. As marine vehicles (MV) get older, the most important maintenance parameters become maintenance costs, reliability and safety. Maintenance models that have been developed in line with marine mechanical systems have been validated using a single system, whose outcome could be different if another PME system is used for validation.
Research limitations/implications
There is a limited literature on MV maintenance parameters and maintenance characterization regarding mechanical systems. The maintenance practices or strategies of marine mechanical systems should be based on maintenance parameters that suit the marine industry for a given PME.
Originality/value
Based on the available literature, the paper provides a variety of maintenance framework, parameters and practices for marine mechanical systems. The paper further gives an insight on what maintenance parameters, strategies and platforms are given preference in the shipping industry.
Details
Keywords
Teodor Sommestad and Amund Hunstad
The expertise of a system administrator is believed to be important for effective use of intrusion detection systems (IDS). This paper examines two hypotheses concerning the…
Abstract
Purpose
The expertise of a system administrator is believed to be important for effective use of intrusion detection systems (IDS). This paper examines two hypotheses concerning the system administrators' ability to filter alarms produced by an IDS by comparing the performance of an IDS to the performance of a system administrator using the IDS.
Design/methodology/approach
An experiment was constructed where five computer networks are attacked during four days. The experiment assessed difference made between the output of a system administrator using an IDS and the output of the IDS alone. The administrator's analysis process was also investigated through interviews.
Findings
The experiment shows that the system administrator analysing the output from the IDS significantly improves the portion of alarms corresponding to attacks, without decreasing the probability that an attack is detected significantly. In addition, an analysis is made of the types of expertise that is used when output from the IDS is processed by the administrator.
Originality/value
Previous work, based on interviews with system administrators, has suggested that competent system administrators are important in order to achieve effective IDS solutions. This paper presents a quantitative test of the value system administrators add to the intrusion detection solution.