Logic function representations play an important role in logic design and computer design, as well as VLSI design. There are many ways to represent a logic function. Presents and…
Abstract
Logic function representations play an important role in logic design and computer design, as well as VLSI design. There are many ways to represent a logic function. Presents and classifies 11 representation methods into “unique representation category” and “non‐unique representation category”. History of these methods is also briefly mentioned. There are three non‐unique representation methods: Boolean expression;sum of products; and product sums, and eight unique representation methods: truth table; canonical sum of products; canonical product of sums; sum of minterms; product of maxterms; Karnaugh map; Boolean lattice; and Venn diagram. A theorem is found which states that Boolean expression, sum of products, product of sums, sum of minterms, product of maxterms, and Karnaugh map, form a lattice structure. The results may have useful applications in knowledge representation, pictorial knowledge representation and other related areas.
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Xiaodong Xia, Weida Chen and Biyu Liu
The purpose of this paper is to investigate the optimal production and financing strategies for the closed-loop supply chain (CLSC) composed of a capital-constrained original…
Abstract
Purpose
The purpose of this paper is to investigate the optimal production and financing strategies for the closed-loop supply chain (CLSC) composed of a capital-constrained original equipment manufacturer (OEM) and a risk-averse authorized remanufacturer (RM).
Design/methodology/approach
The authors formulate four models with different scenarios, namely, the OEM has sufficient capital; the OEM has limited capital without financing; the OEM adopts debt financing strategy; and the OEM adopts equity financing strategy. The equilibrium solutions of each scenario are obtained by backward induction method, the influences of risk aversion coefficient on the equilibrium solutions are examined and the OEM's optimal financing strategy is found by comparison analysis.
Findings
When the OEM's initial capital is limited and the equity dividend ratio is less than a certain threshold, the equity financing strategy is more advantageous for the OEM. However, if the OEM's initial capital is extremely scarce and the dividend proportion is large, the OEM prefers the debt financing strategy. When considering financing, consumer surplus always decreases as the risk aversion factor increases; the debt financing strategy is more environmentally friendly compared with the equity financing strategy. Only the debt financing strategy can make both members in the CLSC achieve a win-win situation in a certain region when the dividend ratio is sufficiently large.
Research limitations/implications
It will be more fascinating if the model extends to such a case that the production operation situation in the CLSC composed of multiple OEMs in multiple periods. Furthermore, the remanufacturer's risk-averse information is asymmetry may be more realistic in our daily life.
Originality/value
There are three main differences from the existing research. One is that the remanufacturer's risk aversion originates from the uncertain remanufacturing cost instead of the uncertain market demand. Another is that the boundary conditions of the OEM prefer to adopt debt financing is obtained through the envelope theorem with Lagrange multiplier method. Last but not the least, this paper provides a good theoretical reference and practical guidance for the OEM to make the rational financing strategy selection in face of different degree of capital scarcity in the CLSC system. The value of the three aspects provides a theoretical basis for the optimal operation decisions of capital-constrained manufacturer considering the remanufacturer's risk aversion in the CLSC operation system.
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Sonette Du Preez, Alyson Johnson, Ryan F. LeBouf, Stephanus J.L. Linde, Aleksandr B. Stefaniak and Johan Du Plessis
This paper aims to measure exposures to airborne contaminants during three-dimensional (3-D) printing and post-processing tasks in an industrial workplace.
Abstract
Purpose
This paper aims to measure exposures to airborne contaminants during three-dimensional (3-D) printing and post-processing tasks in an industrial workplace.
Design/methodology/approach
Contaminant concentrations were assessed using real-time particle number (0.007 to 1 µm) and total volatile organic compound (TVOC) monitors and thermal desorption tubes during various tasks at a manufacturing facility using fused deposition modeling (FDMTM) 3-D printers. Personal exposures were measured for two workers using nanoparticle respiratory deposition samplers for metals and passive badges for specific VOCs.
Findings
Opening industrial-scale FDMTM 3-D printer doors after printing, removing desktop FDMTM 3-D printer covers during printing, acetone vapor polishing (AVP) and chloroform vapor polishing (CVP) tasks all resulted in transient increases in levels of submicrometer-scale particles and/or organic vapors, a portion of which enter the workers’ breathing zone, resulting in exposure. Personal exposure to quantifiable levels of metals in particles <300 nm were 0.02 mg/m3 for aluminum, chromium, copper, iron and titanium during FDMTM printing. Personal exposures were 0.38 to 6.47 mg/m3 for acetone during AVP and 0.18 mg/m3 for chloroform during CVP.
Originality/value
Characterization of tasks provided insights on factors that influenced contaminant levels, and in turn exposures to various particles, metals < 300 nm and organic vapors. These concentration and exposure factors data are useful for identifying tasks and work processes to consider for implementation of new or improved control technologies to mitigate exposures in manufacturing facilities using FDMTM 3-D printers.
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Afghanistan’s ruling Taliban want production to expand to 19,000 b/d shortly. They are counting on the extractives sector to help boost revenue and shore up the flailing economy.
Details
DOI: 10.1108/OXAN-DB284299
ISSN: 2633-304X
Keywords
Geographic
Topical
Dai Q. Tran, Keith R. Molenaar and Bharath Kolli
The purpose of this paper is to investigate procedures and practices to promote transparency in best-value procurement for the design and construction of highway projects with the…
Abstract
Purpose
The purpose of this paper is to investigate procedures and practices to promote transparency in best-value procurement for the design and construction of highway projects with the goal of improving this evolving procurement method.
Design/methodology/approach
The review of published empirical studies, a national survey of transportation agencies, and case studies of highway agencies form the basis of the conclusions in this research. In addition to the national survey, with 46 of 52 agencies participating, the research presents case studies from seven highway agencies in the USA including: California, Florida, Michigan, Minnesota, New York, Oregon, and Utah. These seven case studies were selected from agencies that employ mature best-value procurement methods. The case studies involved a thorough procedural review and structured interviews of agency personnel. The agencies then validated the results and conclusions.
Findings
The results showed that evaluation committees should include technical members who do not have a personal interest in the outcome of the selection to maintain transparency in best-value projects. The committees should receive best-value procurement training, which necessitates the development of consistent and transparent best-value selection procedures. Debriefing meetings should be conducted to provide comments about strengths and weaknesses of each proposal to enhance fairness and transparency of the best-value selection process.
Research limitations/implications
Knowledge of the best-value procurement procedure will allow researchers to better understand the impact of procedures and practices on transparency in selecting best-value projects. The chief limitation of this research is that the primary data were collected from highway agencies in the USA. Any future research should include more data to enhance the validity of this study outside of the public transportation sector.
Practical implications
The result of this research will help transportation agencies and other public owners to improve their best-value procurement procedures. The findings of this research also address the construction and consulting industry’s concern about transparency and fairness of a best-value selection process.
Originality/value
This research is the first attempt to examine the impact of the evaluation committee, best-value training, and debriefings on transparency of best-value selection.
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Virendra Kumar Verma, Sachin S. Kamble, L. Ganapathy and Pradeep Kumar Tarei
The purpose of this study is to identify, analyse and model the post-processing barriers of 3D-printed medical models (3DPMM) printed by fused deposition modelling to overcome…
Abstract
Purpose
The purpose of this study is to identify, analyse and model the post-processing barriers of 3D-printed medical models (3DPMM) printed by fused deposition modelling to overcome these barriers for improved operational efficiency in the Indian context.
Design/methodology/approach
The methodology used interpretive structural modelling (ISM), cross-impact matrix multiplication applied to classification (MICMAC) analysis and decision-making trial and evaluation laboratory (DEMATEL) to understand the hierarchical and contextual relations among the barriers of the post-processing.
Findings
A total of 11 post-processing barriers were identified in this study using ISM, literature review and experts’ input. The MICMAC analysis identified support material removal, surface finishing, cleaning, inspection and issues with quality consistency as significant driving barriers for post-processing. MICMAC also identified linkage barriers as well as dependent barriers. The ISM digraph model was developed using a final reachability matrix, which would help practitioners specifically tackle post-processing barriers. Further, the DEMATEL method allows practitioners to emphasize the causal effects of post-processing barriers and guides them in overcoming these barriers.
Research limitations/implications
There may have been a few post-processing barriers that were overlooked by the Indian experts, which might have been important for other country’s perspective.
Practical implications
The presented ISM model and DEMATEL provide directions for operation managers in planning operational strategies for overcoming post-processing issues in the medical 3D-printing industry. Also, managers may formulate operational strategies based on the driving and dependence power of post-processing barriers as well as the causal effects relationships of the barriers.
Originality/value
This study contributes to identifying, analyzing and modelling the post-processing barriers of 3DPMM through a combined ISM and DEMATEL methodology, which has not yet been reviewed. This study also contributes to decision makers developing suitable strategies to overcome the post-processing barriers for improved operational efficiency.
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JACK McCARTHY reports in New york on the problems United States manufactures have in placing the prodcts in right market position.
This paper aims to analyze visitors’ waiting behavior in corridors of an internal medicine ward in relation to concepts of territoriality and privacy.
Abstract
Purpose
This paper aims to analyze visitors’ waiting behavior in corridors of an internal medicine ward in relation to concepts of territoriality and privacy.
Design/methodology/approach
Waiting activities, visitors’ room numbers and duration of activities were recorded on a floor plan. Results were tallied according to behavioral and architectural zones in which the activity took place.
Findings
Locations that are near patient rooms that provide visual and auditory access are largely used as territorial areas for non-privacy-required activities. Ends of corridors, secondary corridors and staircases were mainly used for activities that required some level of privacy such as grieving.
Research limitations/implications
As is true with post-occupancy evaluations in other single buildings, this research may not be generalizable to all internal medicine wards. Future research could measure whether responding to visitors’ spatial needs could result in lower density and sense of crowding in the corridors, as well as reduce stress and task interruptions and increase efficiency of patient-check rounds.
Practical implications
The findings indicate that internal medicine wards should include waiting areas near the patient rooms for visitors to be able to keep visual and auditory connection with their patients, as well as areas that provide privacy. This may help lower density, sense of crowding, distraction of medical staff, stress and burn-out and errors, as well as increase the efficiency of patient checks.
Originality/value
The ways in which architectural design of internal medicine corridors can support visitors’ activities and environmental needs such as territoriality and privacy is an issue that is rarely examined. This paper also adds an example from a non-Western culture, to a literature that is dominated by examples from Western cultures.
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This paper explores an important yet overlooked concept in place branding literature, unplanned messages. Focusing on unplanned messages, this study aims to contribute to a better…
Abstract
Purpose
This paper explores an important yet overlooked concept in place branding literature, unplanned messages. Focusing on unplanned messages, this study aims to contribute to a better understanding of the concept of spontaneous order in place branding and how to manage the unplanned communication process so as to ensure a high reputational status for a place.
Design/methodology/approach
This paper builds on past research on place brand communication and proposes a conceptual framework for unplanned messages.
Findings
Classification schemes for places and place brands are proposed, contributing to place brand management in three aspects: reviewing of decisions and strategies undertaken, assessing current situation and planning way forward when it comes to priorities for place management and development.
Originality/value
To the best of the authors’ knowledge, this is the first paper that introduces the emergent image and presents a classification scheme for places that contributes to a strategic management program of unplanned messages in place branding.
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Introduction Companies faced with saturated domestic markets have increasingly turned to potential overseas markets. However, international trading involves an additional risk as…
Abstract
Introduction Companies faced with saturated domestic markets have increasingly turned to potential overseas markets. However, international trading involves an additional risk as the firm is faced with foreign exchange exposures. Transactions exposure usually arises between setting the contract price and payment by the buyer or receipt of funds by the seller. A gain or loss, arising from an exchange rate change, is realised on currency conversion. Operating foreign exchange exposure relates to the potential impact on future costs, sales and earnings streams resulting from a change in real exchange rates, that is, deviations from the equilibrium path implied by the Purchasing Power Parity Theorem.