J.I.U. Rubrico, J. Ota, T. Higashi and H. Tamura
This paper aims to develop a scheduler for multiple picking agents in a warehouse that takes into account distance and loading queue delay minimization within the context of…
Abstract
Purpose
This paper aims to develop a scheduler for multiple picking agents in a warehouse that takes into account distance and loading queue delay minimization within the context of minimizing makespan (i.e. picking time).
Design/methodology/approach
The paper uses tabu search to solve the scheduling problem in a more global sense. Each search iteration is enhanced by a custom local search (LS) procedure that hastens convergence by driving a given schedule configuration quickly to a local minimum. In particular, basic operators transfer demand among agents to balance load and minimize makespan. The new load distribution is further improved by considering a vehicle‐routing problem on the picking assignments of the agents with relocated demands. Loading queue delays that may arise from the reassignments are systematically minimized using a fast scheduling heuristic.
Findings
The proposed tabu scheduler greatly improves over a widely practiced scheduling procedure for the given problem. Variants of the tabu scheduler produce solutions that are roughly of the same quality but exhibit considerable differences in computational time.
Research limitations/implications
The proposed methodology is applicable only to the static scheduling problem where all inputs are known beforehand. Furthermore, of the possible delays during picking, only loading queues are explicitly addressed (although this is justifiable, given that these delays are dominant in the problem).
Practical implications
The proposed approach can significantly increase through‐put and productivity in picking systems that utilize multiple intelligent agents (human pickers included), e.g. in warehouses/distribution centers.
Originality/value
The paper addresses a practical scheduling problem with a high degree of complexity, i.e. scheduler explicitly deals with delays while trying to minimize makespan (generally, delays are ignored in the literature to simplify things). In the tabu implementation, an LS procedure is introduced in the metaheuristic loop that enhances the search process by minimizing non‐productive time of picking agents (travel time and delays).
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The purpose of this paper is to investigate the effect of a magnetic field on the flow of a biomagnetic fluid.
Abstract
Purpose
The purpose of this paper is to investigate the effect of a magnetic field on the flow of a biomagnetic fluid.
Design/methodology/approach
The flow takes place in a straight circular duct and the magnetic field is produced by a line dipole placed perpendicularly to the longitudinal axis of the duct.
Findings
The numerical results show that the magnetic field affects the characteristics of the flow, the velocity components and the friction factor, even for medium field intensity. A relation is proposed for the maximum and minimum longitudinal pressure drop in the pipe.
Originality/value
From the present results it is obtained that it is important to take into account the magnetic properties of blood in the various applications that involve blood flow in the presence of a magnetic field.
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Abstract
Purpose
To determine the optimal spare part order‐replacement policy for any high cost single unit complex system in a discrete‐time circumstance.
Design/methodology/approach
The expected total discounted cost over an infinite planning horizon is taken as a criterion of optimality as it allows us to put emphasis on the present behavior of the system.
Findings
The problem under consideration is a two‐dimensional discrete optimization problem (regular ordering time and inventory time limit for the spare are decision variables) which is difficult to handle, in general. However, it is explored that the problem can be reduced to a simple one‐dimensional one and the optimal ordering time is to be determined under the two extreme situations: no replacement of the spare until the original unit fails and replacement of the spare as soon as it is delivered.
Research limitations/implications
For modeling simplicity, deterministic lead time is considered for both regular and expedited orders. A more appropriate assumption would be to consider randomized lead time for both the orders.
Practical implications
The research provides a useful order‐replacement strategy for a single‐unit system where the failure of the unit is better measured by the number of cycles completed before failure rather than the instant of failure.
Originality/value
The work done in this paper carries certain values as any continuous time model for the problem under consideration can be regarded as only an approximate model.
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Ming Gui Tan, Yean Chun Tea, Jee-Hou Ho, Hui-Ting Goh, Hoon Kiat Ng and Ing Kong
Quantitative gait analysis is an important research area to enable physiotherapist to perform systematic studies and health diagnosis of the lower extremity of patients throughout…
Abstract
Quantitative gait analysis is an important research area to enable physiotherapist to perform systematic studies and health diagnosis of the lower extremity of patients throughout the rehabilitation. The quantitative measurement of ambulatory gait can be performed by using convenient and economical wearable sensors outside specialized motion laboratories. In this paper, a sensor system consisting of three tri-axial accelerometers, two flex sensors and four force sensors was developed. Subject testing were carried out to obtain temporal and spatial gait parameters. The performance of the sensor suite is compared to results from camera videos analysed by Kinovea motion tracking software.
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This chapter focuses on the experiences and processes of earthquake recovery to discuss the general state of disaster recovery in Japan. In this way, it is expected that the…
Abstract
This chapter focuses on the experiences and processes of earthquake recovery to discuss the general state of disaster recovery in Japan. In this way, it is expected that the outcome and discussion can provide effective insights for both domestic and international disaster-related efforts. First, the characteristics of natural disasters in Japan are summarized using statistical data. Quantitative and qualitative methods are flexibly used to analyze published data, materials, and semistructured interview data. Published data and materials are collected from various sources. Interview data were gained from diverse interviewees. Then, four case studies of earthquake recovery are introduced and the application of their recovery experiences to future disaster risk reduction is proposed. Finally, conclusions have been drawn from these case studies to show the practical influence of disaster-recovery experiences to regions that are currently experiencing or are likely to experience natural disasters in the future. More specifically, the chapter illustrates what challenges and influences past earthquakes can have on our present preparedness against a Nankai Trough Earthquake, which is predicted to occur in the near future.
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This chapter seeks to answer the question of how food tourists will be in the future based on technology and digitalisation. Therefore, two future food tourist scenarios are…
Abstract
This chapter seeks to answer the question of how food tourists will be in the future based on technology and digitalisation. Therefore, two future food tourist scenarios are proposed: realistic and utopian. More specifically, considering the developing technology, from a realistic perspective, future food tourists are evaluated according to their experiences (virtual food experiences, personalised and hyper-personalised food experiences, interactive tech-based food experiences, and sensory food experiences), information sources and communication, tendencies (seeking transparency and traceability in the food supply chain and sustainability-oriented), and payments. However, a utopian future food tourist was also provided as the second future food tourist scenario. In this scenario, the dimensions of future food tourists include instantaneous food travel thanks to teleportation, brain–computer interface-based food experiences, lab-grown food experiences, and intergalactic food tourism. Since this is the first study providing future food tourist scenarios, it plays a guidance role for service providers and launches a scholarly debate in food tourism literature.
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J.L. Usó‐Domènech and P. Sastre‐Vazquez
The authors continue developing a Linguistic Theory of the Ecological Systems, but in terms of the Semantics. Each symbol (transformed function) is syntactically a lexeme…
Abstract
The authors continue developing a Linguistic Theory of the Ecological Systems, but in terms of the Semantics. Each symbol (transformed function) is syntactically a lexeme, carrying an associate sememe or atomic semantic unit. Each sememe can be decomposed in semes or quantic semantic unities. They are studied and semantic systems, associated with the syntactic, that serve them as suprastructure, in terms of two levels: the quantic and the atomic. Also, it is demonstrated that for all models of the complex reality, there will always exist a most complex model from the syntactic and semantic point of view.
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The Asia‐Pacific Region is the fastest growing area of the world ineconomic terms. Unfortunately, it has also suffered from severalenvironmental and occupational health problems…
Abstract
The Asia‐Pacific Region is the fastest growing area of the world in economic terms. Unfortunately, it has also suffered from several environmental and occupational health problems largely as a result of this rapid growth without attendant safeguards. Highlights problems such as environmental pollution, those relating to sanitation, cigarette smoking, traffic accidents, poisoning from industrial and agricultural chemicals, noise, health of women workers and other psychosocial problems, and recent trends in the health education and environmental improvements. Concludes with a plea for more attention to and collaboration concerning a clean environment.
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Yoshinori Nakata, Tatsuya Yoshimura, Yuichi Watanabe, Hiroshi Otake, Giichiro Oiso and Tomohiro Sawa
The purpose of this paper is to determine the characteristics of healthcare facilities that produce the most efficient inpatient orthopedic surgery using a large-scale medical…
Abstract
Purpose
The purpose of this paper is to determine the characteristics of healthcare facilities that produce the most efficient inpatient orthopedic surgery using a large-scale medical claims database in Japan.
Design/methodology/approach
Reimbursement claims data were obtained from April 1 through September 30, 2014. Input-oriented Banker-Charnes-Cooper model of data envelopment analysis (DEA) was employed. The decision-making unit was defined as a healthcare facility where orthopedic surgery was performed. Inputs were defined as the length of stay, the number of beds, and the total costs of expensive surgical devices. Output was defined as total surgical fees for each surgery. Efficiency scores of healthcare facilities were compared among different categories of healthcare facilities.
Findings
The efficiency scores of healthcare facilities with a diagnosis-procedure combination (DPC) reimbursement were significantly lower than those without DPC (p=0.0000). All the efficiency scores of clinics with beds were 1. Their efficiency scores were significantly higher than those of university hospitals, public hospitals, and other hospitals (p=0.0000).
Originality/value
This is the first research that applied DEA for orthopedic surgery in Japan. The healthcare facilities with DPC reimbursement were less efficient than those without DPC. The clinics with beds were the most efficient among all types of management bodies of healthcare facilities.
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Yuichi Watanabe and Yoshinori Nakata
The purpose of this paper is to examine the association between outpatient orthopedic surgery costs and Japan’s healthcare facilities using a large-scale Japanese medical claims…
Abstract
Purpose
The purpose of this paper is to examine the association between outpatient orthopedic surgery costs and Japan’s healthcare facilities using a large-scale Japanese medical claims database.
Design/methodology/approach
The authors obtained reimbursement claims data for 8,588 patients who underwent orthopedic surgery between April 1 and September 30, 2014 at 3,347 Japanese healthcare facilities. Regression analysis, using ordinary least squares, examined the association between outpatient orthopedic surgery costs and healthcare facility characteristics. By using surgical fees as proxy for the surgical costs, the authors defined three dependent variables: surgical cost for each outpatient orthopedic surgery; pre- and post-operative cost one month before and after a surgical operation; and total cost for each patient. The authors also defined five independent variables, which capture healthcare facility characteristics and patient-specific factors: bed count; whether healthcare facilities are reimbursed in a diagnosis procedure combination system; patient’s age; sex; and anatomical surgical sites.
Findings
The authors analyzed 6,456 outpatient orthopedic surgical cases performed at 3,085 healthcare facilities. There were significant differences in the surgical costs for outpatient orthopedic surgery among different healthcare facilities by total beds (p=0.000). Multivariate regression analysis shows that surgical costs for outpatient orthopedic surgery are positively and significantly associated with healthcare facilities classified by total beds after adjusting for patient-specific characteristics (p<0.05).
Originality/value
This is the first research to examine the association between costs for outpatient orthopedic surgery and healthcare facility characteristics in Japan. This study via the multivariate regression method showed that outpatient orthopedic surgery is likely to cost higher as healthcare facility size increased. The average incremental costs for each outpatient orthopedic surgery per 100 beds were calculated at $48.5 for surgery, $40.7 for pre- and post-operative care, and $89.2 total cost.