• Journal of Korean Society of Industrial and Systems Engineering
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• v.5 no.7
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• pp.9-15
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• 1982

The rectilinear-distance location problem combines the property of being a very appropriate distance measure for a large number of location problems and the property of being very simple to treat analytically. An obvious question to be asked at the optimal point which is obtained by the rectilinear distance method is, "what if the point is not available as a location site\ulcorner." The point may, for example, be inaccessible or may coincide with the location of another structure, a river, or a municipal park. In this case, one approach that may be employed is to construct contour lines (also called iso-cost or level curves) of the cost function. Contour lines provide considerable insight into the shape of the surface of the total cost function as well as a useful means of evaluating alternative locations for the new facility. But, when there is an obstacle which divides the application area into two. The optimal location(which is acquired by the rectilinear distance method) is not coincide with the minimal cost point and the contour line is occasionally of no use, this paper shows the method of finding a way to decide an optimal point of single facility location in this case.this case.

• Management Science and Financial Engineering
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• v.18 no.1
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• pp.1-12
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• 2012

In this paper, we report a case study on the common due-date assignment and scheduling problem in a paper remanufacturing system that produces corrugated cardboards using collected waste papers for a given set of orders under the make-to-order (MTO) environment. Since the system produces corrugated cardboards in an integrated process and has sequence-dependent setups, the problem considered here can be regarded as common due-date assignment and sequencing on a single machine with sequence-dependent setup times. The objective is to minimize the sum of the penalties associated with due-date assignment, earliness, and tardiness. In the study, the earliness and tardiness penalties were obtained from inventory holding and backorder costs, respectively. To solve the problem, we adopted two types of algorithms: (a) branch and bound algorithm that gives the optimal solutions; and (b) heuristic algorithms. Computational experiments were done on the data generated from the case and the results show that both types of algorithms work well for the case data. In particular, the branch and bound algorithm gave the optimal solutions quickly. However, it is recommended to use the heuristic algorithms for large-sized instances, especially when the solution time is very critical.

• Journal of the Korea Society of Computer and Information
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• v.17 no.11
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• pp.141-148
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• 2012

The advance of technologies for human genome makes it possible that the analysis of association between genetic variants and diseases and the application of the results to predict risk or susceptibility to them. Many of those studies carried out in case-control study. For quantitative traits, statistical analysis methods are applied to find single nucleotide polymorphisms (SNP) relevant to the diseases and consider them one by one. In this study, we presented methods to select informative single nucleotide polymorphisms and predict risk for quantitative traits and compared their performance. We adopted two SNP selection methods: one considering single SNP only and the other of all possible pairs of SNPs.

• Clinics in Shoulder and Elbow
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• v.26 no.1
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• pp.64-70
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• 2023

Background: This study aimed to analyze the efficacy of single-dose corticosteroid injection (CSI) administered at 6 weeks postoperative to treat stiffness following arthroscopic rotator cuff repair (ARCR). Methods: In this prospective, multicentric, case-control study, post-ARCR stiffness at 6 weeks was treated with either a single dose of intra-articular CSI (CSI group) or physical therapy with oral analgesics (non-CSI group). Pain intensity according to visual analog scale (VAS), functional outcome using the Constant Murley Shoulder Score, time to return to activities of daily living (ADLs), and retear rate were recorded at 6 weeks, 9 weeks, 12 weeks, 6 months, 12 months, and 18 months postoperatively in both groups. Results: A total of 149 patients (54.5%) in the CSI group and 124 patients (45.5%) in the non-CSI group were included in this study. Pain and function were significantly better in the CSI group at 9-week, 12-week, and 6-month (P<0.001) follow-up, whereas they were not significantly different when the groups were compared at 12- and 18-month follow-up. The mean duration to return to ADLs was significantly shorter (P<0.001) in the CSI group. The incidence of retears was not significantly different (P=0.36) between groups at the end of 18 months of follow-up. Conclusions: Single-dose intra-articular CSI administered at 6 weeks postoperative to treat post-ARCR stiffness significantly improved pain, function, and duration of return to ADLs without increasing the risk of retears compared to patients who did not receive intra-articular CSI. Level of evidence: III.

• The Journal of Engineering Geology
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• v.26 no.3
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• pp.361-370
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• 2016

This study was performed in order to evaluate the efficiency of groundwater well installed in alluvial aquifer that has filter layers, using laboratory experiment. We manufactured test equipment that can simulate dual filter layer and single filter layer and evaluated the initial volume of water intake, pumping efficiency, and long term stability using the experiment and analysis. In an early stage within 60 minutes, the case that took the dual filter showed an increase of 19.4 % in the initial volume of water intake compared to the case without it. It was found that after 24 hours of the test, the well installed with the dual filter showed higher than 68.9% compared to the well with single filter. It was calculated that it took 1.35 days to reach the point corresponding to the half of the water intake in case of single filter while it took 38.66 days to do so in case of dual filter. Therefore, it is highly recommended that the well with dual filter is much more favorable in the long term stability.

• Imaging Science in Dentistry
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• v.54 no.1
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• pp.109-113
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• 2024

A 54-year-old male patient presented for a periodic check-up at the dental clinic. A panoramic radiograph showed bilateral ossification of the stylohyoid ligament with an oval radiopacity on the right side. Cone-beam computed tomography revealed a well-defined, homogenous hyperdense entity from the lower third of the ossified stylohyoid ligament on the right side. The differential diagnosis of osteoma on the stylohyoid chain includes Eagle syndrome and benign tumors of the stylohyoid chain and adjacent structures. Osteoma rarely manifests in the neck. Even more infrequent are tumors originating from the stylohyoid chain, with only a single documented case of osteoma reported in the literature in 1993. Due to the asymptomatic status, no surgical intervention was advised, and the case would be monitored periodically. This case report describes the details of an osteoma that emerged from the stylohyoid chain, marking it as the second recorded occurrence of this highly rare condition.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.4
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• pp.259-268
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• 1993

The downdrag on a single pile and on pile groups was examined by using a numerical analysis and an analytical study. The overall objective of the present study was given to the magnitude and distribution of the downdrag forces on piles within a group. The case of the single pile was analyzed by developing a closed form solution. Subsequently the response of groups was investigated by using a detailed numerical approach. Based on the results, it is found that the downdrag load of piles in a group is much smaller than that of a single pile. Also, a simple method is proposed to design groups of 9 to 25 piles with spacing-to-diameter ratios varying from 2.5 to 5.0 for downdrag loads.

• Earthquakes and Structures
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• v.11 no.5
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• pp.905-924
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• 2016

Several two-dimensional analytical beam column joint models with varying complexities have been proposed in quantifying joint flexibility during seismic vulnerability assessment of non-ductile reinforced concrete (RC) frames. Notable models are the single component rotational spring element and the super element joint model that can effectively capture the governing inelastic mechanisms under severe ground motions. Even though both models have been extensively calibrated and verified using quasi-static test of joint sub-assemblages, a comparative study of the inelastic seismic responses under nonlinear time history analysis (NTHA) of RC frames has not been thoroughly evaluated. This study employs three hypothetical case study RC frames subjected to increasing ground motion intensities to study their inherent variations. Results indicate that the super element joint model overestimates the transient drift ratio at the first story and becomes highly un-conservative by under-predicting the drift ratios at the roof level when compared to the single-component model and the conventional rigid joint assumption. In addition, between these story levels, a decline in the drift ratios is observed as the story level increased. However, from this limited study, there is no consistent evidence to suggest that care should be taken in selecting either a single or multi component joint model for seismic risk assessment of buildings when a global demand measure such as maximum inter-storey drift is employed in the seismic assessment framework.

• The Journal of Internal Korean Medicine
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• v.19 no.2
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• pp.438-450
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• 1998

Pleural effusion means the inflammation of pleura which has a majority of respiratory disease. The main clinical manifestation is pleural effusional pain, dyspnea, cough, fever, etc. and at present the Tuberculous pleural effusion has the most frequency in which exists exudate in our country. And during studying oriental medical treatment about Tuberculous exudative pleural effusional patient, we found the clinical case about The Combination therapy of Chinese traditional and Western medicine at journal of traditional Chinese Medicine and considered it would be help in oriental medical treatment, so we adjust and report now. This study was performed by analyzing the six papers reported centering around the clinical case of The Combination therapy of Chinese traditional and Western medicine in journal of traditional Chinese Medicine published between 1990-1996. As these papers have no mistakes on diagnosis because it obtained pleurocentesis, tuberculin test positive reaction on choicing clinical case, definite results on X-ray, ultrasound as well as clinical basis, so it considers an apt conclusion. The results were as follows: 1. Western medical treatment uses chemical remedy same with pulmonary tuberculosis, and in case of tubercular pleuritis, it needs thoracic duct pyorrhea, and according to simple exudation also operates therapheutic pleural paracentesis. 2. In case of hydrothorax absorption about tuberculous pleural effusion, prescription of purge the heat accumulated in the lung and eliminate the retention of fluid with powerful purgatives shows considerable effects. 3. The latter period treatment of tuberculous pleural effusion needs Supplement qi and active the collaterals, Nourishing yin and clearing heat in addition to Supporting healthy energy to eliminate evils. 4. In case of curing tuberculous pleural effusion, The Combination therapy of Chinese traditional and Western medicine shows more considerable effect than single western medical treatment in absorption of hydrothorax. 5. In case of curing tuberculous pleural effusion, The Combination therapy of Chinese traditional and Western medicine shows more considerable effect than single western medical treatment in prevention of disease reappearance. 6. In case of curing tuberculous pleural effusion, The Combination therapy of Chinese traditional and Western medicine shows more considerable effect than single western medical treatment in vitality recovery at the latter period of disease.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.4
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• pp.83-96
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• 2020

Traditionally social problems had been largely left to be handled by non-profit organizations, not because of lack of interests in social causes but mostly because of lack of innovative ideas to solve them in commercially viable ways. This market failure has recently been fixed by social enterprises, which manage to provide both solutions for social issues and commercially viable business models. As a result, we have been witnessing a sudden spike of public interests in these social enterprises as well as a call for empirical investigation on social enterprises by prior studies. However, empirically investigating a social enterprise has been a challenging endeavor mostly due to the insufficient number of successful social enterprises. Answering to the call in this study, we empirically investigate Goyohan Taxi, a successful social enterprise that partners with visually impaired cabdrivers and offers a taxi service, by both longitudinally interviewing the founder and adopting in vivo observation throughout the entrepreneurial journey of Goyohan Taxi. Based on the single case study method, we find that Goyohan Taxi adopts two distinctive decision-making mechanisms, the de-escalation of commitment and the orthogonality of commercial and social goals. Although generalizability of the our finding is minimal due to the limitation of single case study method, our finding contributes to the research of social entrepreneurship by offering new avenue of research in decision-making process of social entrepreneurs.