• Sleep Medicine and Psychophysiology
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• v.19 no.2
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• pp.68-76
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• 2012

Objectives: Sleep disorders cause changes of autonomic nervous system (ANS) which affect cardiovascular system. Primary insomnia (PI) makes acceleration of sympathetic nervous system (SNS) tone by sleep deficiency and arousal. Obstructive sleep apnea syndrome (OSAS) sets off SNS by frequent arousals and hypoxemias during sleep. We aimed to compare the changes of heart rate variability (HRV) indices induced by insomnia or sleep apnea to analyze for ANS how much to be affected by PI or OSAS. Methods: Total 315 subjects carried out nocturnal polysomnography (NPSG) were categorized into 4 groups - PI, mild, moderate and severe OSAS. Severity of OSAS was determined by apnea-hypopnea index (AHI). Then we selected 110 subjects considering age, sex and valance of each group's size [Group 1 : PI (mean age=$41.50{\pm}13.16$ yrs, AHI <5, n=20), Group 2 : mild OSAS (mean age=$43.67{\pm}12.11$ yrs, AHI 5-15, n=30), Group 3 : moderate OSAS (mean age $44.93{\pm}12.38$ yrs, AHI 16-30, n=30), Group 4 : severe OSAS (mean age=$45.87{\pm}12.44$ yrs, AHI >30, n=30)]. Comparison of HRV indices among the four groups was performed with ANCOVA (adjusted for age and body mass index) and Sidak post-hoc test. Results: We found statistically significant differences in HRV indices between severe OSAS group and the other groups (PI, mild OSAS and moderate OSAS). And there were no significant differences in HRV indices among PI, mild and moderate OSAS group. In HRV indices of PI and severe OSAS group showing the most prominent difference in the group comparisons, average RR interval were $991.1{\pm}27.1$ and $875.8{\pm}22.0$ ms (p=0.016), standard deviation of NN interval (SDNN) was $85.4{\pm}6.6$ and $112.8{\pm}5.4$ ms (p=0.022), SDNN index was $57.5{\pm}5.2$ and $87.6{\pm}4.2$ (p<0.001), total power was $11,893.5{\pm}1,359.9$ and $18,097.0{\pm}1,107.2ms^2$(p=0.008), very low frequency (VLF) was $7,534.8{\pm}1,120.1$ and $11,883.8{\pm}912.0ms^2$ (p=0.035), low frequency (LF) was $2,724.2{\pm}327.8$ and $4,351.6{\pm}266.9ms^2$(p=0.003). Conclusions: VLF and LF which were correlated with SNS tone showed more increased differences between severe OSAS group and PI group than other group comparisons. We could suggest that severe OSAS group was more influential to increased SNS activity than PI group.

• Tuberculosis and Respiratory Diseases
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• v.44 no.2
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• pp.379-390
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• 1997

Background : It has long been suggested that neutrophils and their products are implicated as the central mediators of the acute lung injuries. Contrary to the dominant role of neutrophils in ARDS, many cases of ARDS has occurred in the setting of severe neutropenia without pulmonary neutrophil infiltration. Therefore it is certain that effector cell(s) other than neutrophil play an important role in the pathogenesis of ARDS. This experiment was performed to define the mechanism of ARDS in the setting of neutropenia, 1) by comparing the severity of endotoxin-induced lung injury, 2) by measurement of hydrogen peroxide production and cytokine concentration in the bronchoalveolar lavage cells and fluids obtained from different rats with and without cyclophosphamide-pretreatment. Method : The male Sprague-Dawleys were divided into the normal control (NC)-, endotoxin (ETX)-, and cyclophosphamide (CPA)-group in which neutropenia was induced by injecting cyclophosphamide intraperitoneally. Acute lung injury was evoked by injecting lipopolysaccharide (LPS) into a tail vein. The bronchoalveolar lavage (BAL) was performed at 3 and 6 hour after administration of LPS to measure the change of cell counts and concentrations of protein and cytokines, tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6). Hydrogen peroxide (HPO) production from BAL cells was measured at 6 hour after LPS administration by phenol red microassay with and without zymosan stimulation. Results : The results were as follows. A change of leukocyte counts in the peripheral blood after treatment with CPA : More than 95% of total leukocytes and neutrophils were reduced after CPA administration, resulting in severe neutropenia. A change of BAL cells : In the ETX-group, the number of total cells (p < 0.01) and of macrophage and neutrophil (p < 0.05) were increased at 3 and 6 hour after LPS administration compared to those of NC-group. In the CPA-group, the number of total leukocyte and macrophage were not changed after LPS administration, but neutrophil counts were significantly reduced and it took part in less than 0.1% of total BAL cells (p < 0.01 vs NC-group). BAL cells in this group were almost all macrophages (99.7%). A change of protein concentration in the BALF : In the ETX-group, protein concentration was increased at 3 hour and was more increased at 6 hour after LPS administration (p < 0.05 and < 0.01 vs NC-group, respectively). In the CPA-group, it was also significantly elevated at 3 hour after LPS administration (p < 0.05 vs NC-group), but the value was statistically not different from that of ETX-group. The value measured at 6 hour after LPS administration in the CPA-group became lower than that of ETX-group (p < 0.05), but showed still a higher value compared to that of NC-group (p < 0.05). A change of cytokine concentration in the BALF : TNF -alpha and IL-6 were elevated in the ETX - and CPA-group compared to those of NC-group at both time intervals. There was no statistical difference in the values of both cytokines between the ETX- and CPA-groups. Measurement of hydrogen peroxide production from BAL cells : There was no intergroup difference of HPO production from resting cells. HPO production after incubation with opsonized zymosan was significantly elevated in all groups. The percent increment of HPO production was highest in the ETX-group (89.0%, p < 0.0008 vs NC-group), and was 42.85 in the CPA-group (p = 0.003 vs NC-group ). Conclusion : Acute lung injury in the setting of neutropenia might be caused by functional activation of resident alveolar macrophages.

• Tuberculosis and Respiratory Diseases
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• v.44 no.2
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• pp.280-289
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• 1997

Background : Bronchioloalveolar carcinoma (BAC) has been reported to diveres spectrum of chinical presentations and radiologic patterns. The three representative radiologic patterns are followings ; 1) a solitary nodule or mass, 2) a localized consolidation, and 3) multicentric or diffuse disease. While, the localized consolidation and solitary nodular patterns has favorable prognosis, the multicentric of diffuse pattern has worse prognosis regardless of treatment. BAC presenting as a solitary pulmonary nodule is often misdiagnosed as other benign disease such as tuberculoma. Therefore it is very important to make proper diagnosis of BAC with solitary nodular pattern, since this pattern of BAC is usually curable with a surgical resection. Methods : We reviewed the clinical and radiologic features of patients with pathologically-proven BAC with solitary nodular pattern from January 1995 to September 1996 at Samsung Medical Center. Results : Total 11 patients were identified. 6 were men and 5 were women. Age ranged from 37 to 69. Median age was 60. Most patients with BAC with solitary nodular pattern were asymptomatic and were detected by incidental radiologic abnormality. The chest radiograph showed poorly defined opacity or nodule and computed tomography showed consolidation, ground glass appearance, internal bubble-like lucencies, air bronchogram, open bronchus sign, spiculated margin or pleural tag in most patients. The initial diagnosis on chest X-ray were pulmonary tuberculosis in 4 patients, benign nodule in 2 patients and malignant nodule in 5 patients. The FDG-positron emission tomogram was performed in eight patients. The FDG-PET revealed suggestive findings of malignancy in only 3 patients. The pathologic diagnosis was obtained by transbronchial lung biopsy in 1 patient, by CT guided percutaneous needle aspiration in 2 patients, and by lung biopsy via video-assited thoracocopy in 8 patients. Lobectomy was performed in all patients and postoperative pathologic staging were $T_1N_0N_0$ in 8 patients and $T_2N_0M_0$ in 3 patients. Conclusion : Patients of BAC presenting with solitary nodular pattern were most often asymptomatic and incidentally detected by radiologic abnormality. The chest X-ray showed poorly defined nodule or opacity and these findings were often regarded as benign lesion. If poorly nodule or opacity does not disappear on follow up chest X-ray, computed tomography should be performed. If consolidation, ground glass appearance, open bronchus sign, air bronchogram, internal bubble like lucency, pleural tag or spiculated margin are found on computed tomography, further diagnostic procedures, including open thoracotomy, should be performed to exclude the possiblity of BAC with solitary nodular pattern.

• Tuberculosis and Respiratory Diseases
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• v.47 no.6
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• pp.775-785
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• 1999

Background : Though surgery plays an important role in the management of patients with Mycobacterium tuberculosis infection, there is little information regarding the timing of resection. We tried to find out the ideal timing of operation. Method: A retrospective review was performed in 69 patients underwent pulmonary resection for pulmonary tuberculosis between January 1993 and December 1997. They were categorized into various groups according to the length of preoperative specific drug therapy. The rates of treatment failure, realpse and complication in each group were compared statistically by $x^2$-test. Results: Eighty one point two percent were men and 18.8 % women with a median age of 33 years(range, 16 to 63 years). The mean number of resistant drugs was 3.l(range, 0 to 9). Patients were treated preoperatively with multidrug regimens, which mean number of preoperative specific drugs was 4.6, in an effort to reduce the mycobacterial burden with the mean length of preoperative drug therapy, 5.0 months. Postoperative treatment was conducted for a mean period of 13.0 months with a mean number of postoperative specific drugs, 4.4. Postoperative treatment failures were confirmed in 8 among 69 patients(11.6%). 2 of these 8 patients were showed up in the preoperative 3 to 4 months medication group and each of the rest was occurred in the preoperative 2 to 3, 5 to 6, 6 to 7, 12 to 13, 17 to 18 months, less than one month medication group, respectively. 59 of 69 patients were available for evaluation of the relapse rate with the mean duration of the postoperative follow-up, 19.8 months. In 4 patients bacterial relapse was confirmed(6.8%). Each of these 4 was in the preoperative 1 to 2, 2 to 3, 3 to 4, 5 to 6 months medication group. Categorized into various groups according to the length of preoperative specific therapy, there were no statistical significances of the treatment failure rate, relapse rate and complication rate in the groups. There were seven treatment failures of 28 who were AFB culture positive until the time of operation(25%, p<0.01). Categorized the preoperative AFB culture positive group into various groups according to the length of preoperative drug therapy, there were no statistical significances, either. Conclusion: We believe that operation plays an important ancillary role in the treatment of pulmonary tuberculosis. Our results indicate that the timing of resection according to the length of preoperative drug therapy may not cause trouble.

• Tuberculosis and Respiratory Diseases
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• v.45 no.1
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• pp.57-67
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• 1998

Purpose : This study was undertaken to determine the preoperative predictors of mortality and morbidity after lung cancer resection. Method: During the period from October 1, 1995 to August 31, 1996, a prospective study was conducted in 92 lung resection candidates diagnosed as lung cancer. For preoperative predictors of nonpulmonary factors, we considered age, sex, weight loss, hematocrit, serum albumin, EKG and concomitant illness, and for those of pulmonary factors, smoking history, presence of pneumonia, dyspnea scale(1 to 4), arterial blood gas analysis with room air breathing, routine pulmonary function test. And predicted postoperative(ppo) pulmonary factors such as PPO-$FEV_1$, ppo-diffusing capacity(DLco), predicted postoperative product(PPP) of ppo-$FEV_1%{\times}ppo$-DLco% and ppo-maximal $O_2$ uptake($VO_2$max) were also considered. Results: There were 78 men and 14 women with a median age of 62 years(range 42 to 82) and a mean $FEV_1$ of $2.37\pm0.06L$. Twenty nine patients had a decreased $FEV_1$ less than 2.0L. Pneumonectomy was performed in 26 patients, bilobectomy in 12, lobectomy in 54. Pulmonary complications developed in 10 patients, cardiac complications in 9, other complications(empyema, air leak, bleeding) in 11, and 16 patients were managed in intensive care unit for more than 48hours. Three patients died within 30 days after operation. The ppo-$VO_2$max was less than 10ml/kg/min in these three patients, but its statistical significance could not be determined due to small number of patients. In multivariate analysis, the predictor related to postoperative death was weight loss(p<0.05), and as for pulmonary complications, weight loss, dyspnea scale, ppo-DLco and extent of resection(p<0.05). Conclusions: Based on this study, preoperative nonpulmonary factors such as weight loss and dyspnea scale are more important than the pulmonary factors in the prediction of postoperative mortality and/or morbodity in lung resection candidates, but exercise pulmonary fuction test may be useful Our study suggests that ppo-$VO_2$max value less than 10ml/kg/min is associated with death after lung cancer resection but further studies are needed to validate this result.

• Tuberculosis and Respiratory Diseases
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• v.43 no.6
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• pp.882-893
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• 1996

Background : Over one-third of solitary pulmonary nodules are malignant, but most malignant SPNs are in the early stages at diagnosis and can be cured by surgical removal. Therefore, early diagnosis of malignant SPN is essential for the lifesaving of the patient. The incidence of pulmonary tuberculosis in Korea is somewhat higher than those of other countries and a large number of SPNs are found to be tuberculoma. Most primary physicians tend to regard newly detected solitary pulmonary nodule as tuberculoma with only noninvasive imaging such as CT and they prefer clinical observation if the findings suggest benignancy without further invasive procedures. Many kinds of noninvasive procedures for confirmatory diagnosis have been introduced to differentiate malignant SPNs from benign ones, but none of them has been satisfactory. FOG-PET is a unique tool for imaging and quantifying the status of glucose metabolism. On the basis that glucose metabolism is increased in the malignant transfomled cells compared with normal cells, FDG-PET is considered to be the satisfactory noninvasive procedure which can differentiate malignant SPNs from benign SPNs. So we performed FOG-PET in patients with solitary pulmonary nodule and evaluated the diagnostic accuracy in the diagnosis of malignant SPNs. Method : 34 patients with a solitary pulmonary nodule less than 6 cm of irs diameter who visited Samsung Medical Center from Semptember, 1994 to Semptember, 1995 were evaluated prospectively. Simple chest roentgenography, chest computer tomography, FOG-PET scan were performed for all patients. The results of FOG-PET were evaluated comparing with the results of final diagnosis confirmed by sputum study, PCNA, fiberoptic bronchoscopy, or thoracotomy. Results : (I) There was no significant difference in nodule size between malignant (3.1 1.5cm) and benign nodule(2.81.0cm)(p>0.05). (2) Peal SUV(standardized uptake value) of malignant nodules (6.93.7) was significantly higher than peak SUV of benign nodules(2.71.7) and time-activity curves showed continuous increase in malignant nodules. (3) Three false negative cases were found among eighteen malignant nodule by the FDG-PET imaging study and all three cases were nonmucinous bronchioloalveolar carcinoma less than 2 em diameter. (4) FOG-PET imaging resulted in 83% sensitivity, 100% specificity, 100% positive predictive value and 84% negative predictive value. Conclusion: FOG-PET imaging is a new noninvasive diagnostic method of solitary pulmonary nodule thai has a high accuracy of differential diagnosis between malignant and benign nodule. FDG-PET imaging could be used for the differential diagnosis of SPN which is not properly diagnosed with conventional methods before thoracotomy. Considering the high accuracy of FDG-PET imaging, this procedure may play an important role in making the dicision to perform thoracotomy in diffcult cases.

• Journal of Korean Society of Forest Science
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• v.38 no.1
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• pp.33-45
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• 1978

The purpose of present study is to analyze the genetic variation of natural stand of Pinus densiflora. In 1975 following after the selection of 1974, twenty trees from each of three natural populations of the species were selected and their open-pollinated seeds were collected, and the locations and conditions of the populations ate presented in table 1, 2 and figure 1. Some morphological traits of the populations were already detailed in our second report of this series, in which Myong-Ju and Ul-Jin populations were regarded to be superior phenotypically to suweon population. The morphological traits of cone, seed and seed-wing, and also the growth performances and needle characters of the seedling were observed in the present study according to the previous methods. The results obtained are summarized as follows; 1. The meteorological data obtained by averaging the records of 30 year period (1931~1960) measured from the nearest meteorological stations to each population are shown in fig.2, 3, 4. The distributional patterns of investigated climate factors are generally considered to be similar among the locations. However, the precipitation density during growing season and the air temperature during dormant season on Suweon area, population 6, were quite different from those of the other areas. 2. The measurements of fresh cone weight, length, diameter and cone index, i.e., length to diameter ratio are presented in table 7. As shown in table 7, all these traits except for cone diameter seem to be highly significant in population differences and family differences within population. 3. The morphological traits of seed and seed-wing are detailed in table 8, 9, and highly significant differences are recognized among the populations and the families within population in seed-wing length, seed-wing index, seed weight, seed-length and seed index but not among the populations in the other observed traits. The values of correlation coefficient between the characters of cone and seed are given in table 10 and the positive significant correlations can be observed in the most parts of the compared traits. 4. Significant statistical differences among populations and families within population are observed in the growth performances of 1-0 and 1-1 seedling height of these progenies. But the differences in root collar diameter are shown only among families within population. As shown in table 13, the most parts of correlations are not significant statistically between the growth performances of seedling and the seed characters. 5. The number of stomata row on both sides of needle and the serration density were measured in the seedlings from each of the families of the three populations. As shown in table 15, statistical differences are considered to be significant among the populations and among the families within population in serration density but not among the populations in stomata row on both sides of the needle. The results differ from those of the third report of this series. Even if one of the reason seems to be the diversity of selected populations, it could not be confirmed definitely. The correlations between progenies and parents are not generally observed in the investigated traits of needle as shown in table 16.

• Journal of Korean Society of Forest Science
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• v.71 no.1
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• pp.14-21
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• 1985

This study was carried out in order to prevent the devaluation of wood itself and wood products causing by anisotropy, hygroscopicity, shrinkage and swelling - properties that wood itself only have, in order to improve utility of wood, by emphasizing the natural beautiful figures of wood, to develop the dimensional stabilization techniques of wood with PEG that it is a cheap, non-toxic and the impregnation treatment is not difficult, on the effects of PEG molecular weights (200, 400, 600, 1000, 1500, 2000, 4000, 6000) and species (Pinus densiflora S. et Z., Larix leptolepis Gordon., Cryptomeria japonica D. Don., Cornus controversa Hemsl., Quercus variabilis Blume., Prunus sargentii Rehder.). The results were as follows; 1) PEG loading showed the maximum value (137.22%, Pinus densiflora, in PEG 400), the others showed that relatively slow decrease. The lower specific gravity, the more polymer loading. 2) Bulking coefficient didn't particularly show the correlation with specific gravity, for the most part, indicated the maximum values in PEG 600, except that the bulking coefficient of Quercus variabilis distributed between the range of 12-18% in PEG 400-2000. In general, the bulking coefficient of hardwood was higher than that of softwood. 3) Although there was more or less an exception according to species, volumetric swelling reduction was the greatest in PEG 400. That is, its value of Cryptomeria japonica was the greatest value with 95.0%, the others indicated more than 80% except for Prunus sargentii, while volumetric swelling reduction was decreased less than 70% as the molecular weight increase more than 1000. 4) The relative effectiveness of hardwood with high specific gravity was outstandingly higher than softwood. In general, the relative effectiveness of low molecular weight PEG was superior to those of high molecular weight PEG except that Quercus variabilis showed more than 1.6 to the total molecular weight range, while it was no significant difference as the molecular weight increase more than 4000. 5) According to the analysis of the results mentioned above, the dimensional stabilization of hardwood was more effective than softwood. Although volumetric swelling reduction was the greatest at a molecular weight of 400. In the view of polymer loading, bulking coefficiency reduction of swelling and relative effectiveness, it is desirable to use the mixture of PEG of molecular weight in the range of 200-1500. To practical use, it is recommended to study about the effects on the mixed ratio on the bulking coefficient, reduction of swelling and relative effectiveness.

• Journal of Intelligence and Information Systems
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• v.19 no.4
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• pp.21-37
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• 2013

Recently, as the advent of the knowledge-based society, there are more people getting interested in the intellectual property. Especially, the ICT companies leading the high-tech industry are working hard to strive for systematic management of intellectual property. As we know, the patent information represents the intellectual capital of the company. Also now the quantitative analysis on the continuously accumulated patent information becomes possible. The analysis at various levels becomes also possible by utilizing the patent information, ranging from the patent level to the enterprise level, industrial level and country level. Through the patent information, we can identify the technology status and analyze the impact of the performance. We are also able to find out the flow of the knowledge through the network analysis. By that, we can not only identify the changes in technology, but also predict the direction of the future research. In the field using the network analysis there are two important analyses which utilize the patent citation information; citation indicator analysis utilizing the frequency of the citation and network analysis based on the citation relationships. Furthermore, this study analyzes whether there are any impacts between the size of the company and patent citation relationships. 74 S&P 500 registered companies that provide IT and communication services are selected for this study. In order to determine the relationship of patent citation between the companies, the patent citation in 2009 and 2010 is collected and sociomatrices which show the patent citation relationship between the companies are created. In addition, the companies' total assets are collected as an index of company size. The distance between companies is defined as the absolute value of the difference between the total assets. And simple differences are considered to be described as the hierarchy of the company. The QAP Correlation analysis and MR-QAP analysis is carried out by using the distance and hierarchy between companies, and also the sociomatrices that shows the patent citation in 2009 and 2010. Through the result of QAP Correlation analysis, the patent citation relationship between companies in the 2009's company's patent citation network and the 2010's company's patent citation network shows the highest correlation. In addition, positive correlation is shown in the patent citation relationships between companies and the distance between companies. This is because the patent citation relationship is increased when there is a difference of size between companies. Not only that, negative correlation is found through the analysis using the patent citation relationship between companies and the hierarchy between companies. Relatively it is indicated that there is a high evaluation about the patent of the higher tier companies influenced toward the lower tier companies. MR-QAP analysis is carried out as follow. The sociomatrix that is generated by using the year 2010 patent citation relationship is used as the dependent variable. Additionally the 2009's company's patent citation network and the distance and hierarchy networks between the companies are used as the independent variables. This study performed MR-QAP analysis to find the main factors influencing the patent citation relationship between the companies in 2010. The analysis results show that all independent variables have positively influenced the 2010's patent citation relationship between the companies. In particular, the 2009's patent citation relationship between the companies has the most significant impact on the 2010's, which means that there is consecutiveness regarding the patent citation relationships. Through the result of QAP correlation analysis and MR-QAP analysis, the patent citation relationship between companies is affected by the size of the companies. But the most significant impact is the patent citation relationships that had been done in the past. The reason why we need to maintain the patent citation relationship between companies is it might be important in the use of strategic aspect of the companies to look into relationships to share intellectual property between each other, also seen as an important auxiliary of the partner companies to cooperate with.

• Journal of Intelligence and Information Systems
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• v.19 no.4
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• pp.55-79
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• 2013

In this paper, we propose a hybrid genetic algorithm (HGA) approach to effectively solve the reverse logistics network with centralized centers (RLNCC). For the proposed HGA approach, genetic algorithm (GA) is used as a main algorithm. For implementing GA, a new bit-string representation scheme using 0 and 1 values is suggested, which can easily make initial population of GA. As genetic operators, the elitist strategy in enlarged sampling space developed by Gen and Chang (1997), a new two-point crossover operator, and a new random mutation operator are used for selection, crossover and mutation, respectively. For hybrid concept of GA, an iterative hill climbing method (IHCM) developed by Michalewicz (1994) is inserted into HGA search loop. The IHCM is one of local search techniques and precisely explores the space converged by GA search. The RLNCC is composed of collection centers, remanufacturing centers, redistribution centers, and secondary markets in reverse logistics networks. Of the centers and secondary markets, only one collection center, remanufacturing center, redistribution center, and secondary market should be opened in reverse logistics networks. Some assumptions are considered for effectively implementing the RLNCC The RLNCC is represented by a mixed integer programming (MIP) model using indexes, parameters and decision variables. The objective function of the MIP model is to minimize the total cost which is consisted of transportation cost, fixed cost, and handling cost. The transportation cost is obtained by transporting the returned products between each centers and secondary markets. The fixed cost is calculated by opening or closing decision at each center and secondary markets. That is, if there are three collection centers (the opening costs of collection center 1 2, and 3 are 10.5, 12.1, 8.9, respectively), and the collection center 1 is opened and the remainders are all closed, then the fixed cost is 10.5. The handling cost means the cost of treating the products returned from customers at each center and secondary markets which are opened at each RLNCC stage. The RLNCC is solved by the proposed HGA approach. In numerical experiment, the proposed HGA and a conventional competing approach is compared with each other using various measures of performance. For the conventional competing approach, the GA approach by Yun (2013) is used. The GA approach has not any local search technique such as the IHCM proposed the HGA approach. As measures of performance, CPU time, optimal solution, and optimal setting are used. Two types of the RLNCC with different numbers of customers, collection centers, remanufacturing centers, redistribution centers and secondary markets are presented for comparing the performances of the HGA and GA approaches. The MIP models using the two types of the RLNCC are programmed by Visual Basic Version 6.0, and the computer implementing environment is the IBM compatible PC with 3.06Ghz CPU speed and 1GB RAM on Windows XP. The parameters used in the HGA and GA approaches are that the total number of generations is 10,000, population size 20, crossover rate 0.5, mutation rate 0.1, and the search range for the IHCM is 2.0. Total 20 iterations are made for eliminating the randomness of the searches of the HGA and GA approaches. With performance comparisons, network representations by opening/closing decision, and convergence processes using two types of the RLNCCs, the experimental result shows that the HGA has significantly better performance in terms of the optimal solution than the GA, though the GA is slightly quicker than the HGA in terms of the CPU time. Finally, it has been proved that the proposed HGA approach is more efficient than conventional GA approach in two types of the RLNCC since the former has a GA search process as well as a local search process for additional search scheme, while the latter has a GA search process alone. For a future study, much more large-sized RLNCCs will be tested for robustness of our approach.