• Journal of Korean Society of Forest Science
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• v.84 no.2
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• pp.121-130
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• 1995

Forecasting accuracy is examined in the context of Michigan travel demand. Eight different annual models are used to forecast up to two years ahead, and nine different quarterly models up to four quarters. In the evaluation of annual models' performance, multiple regression performed better than the other methods in both the one year and two year forecasts. For quarterly models, Winters exponential smoothing and the Box-Jenkins method performed better than naive 1 s in the first quarter ahead, but these methods in the second, third, and fourth quarters ahead performed worse than naive 1 s. The sophisticated models did not outperform simpler models in producing quarterly forecasts. The best model, multiple regression, performed slightly better when fitted to quarterly rather than annual data: however, it is not possible to strongly recommend quarterly over annual models since the improvement in performance was slight in the case of multiple regression and inconsistent across the other models. As one would expect, accuracy declines as the forecasting time horizon is lengthened in the case of annual models, but the accuracy of quarterly models did not confirm this result.

• Asia pacific journal of information systems
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• v.19 no.1
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• pp.83-111
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• 2009

Despite the growing emphasis on the importance of knowledge exchange among supply chain participants, few companies have fully exploited the knowledge resources held by their supply chain partners. Among many reasons for this phenomenon, recent literature on inter-firm knowledge exchange identifies knowledge complementarities between the supply channel partners as an important determinant of knowledge exchange. Firms participating in a supply chain are likely to exchange partners' complementary knowledge. In order to extract value from them, it is important to recognize the difference between the potential value and the implementation of this potential value. However, the literature fails to distinguish between potential knowledge complementarities and implemented knowledge complementarities. In order to realize the value of potential knowledge complementarities, knowledge should be exchanged and effectively integrated in the supply channel. Further, investigating inter-firm knowledge exchange from both partners' perspectives is important especially when there are interdependencies between the channel partners. The purpose of this research is to investigate the impact of potential knowledge complementarities on knowledge exchange in buyer-supplier relationships by looking at both partners' perspectives. This research also includes trust in partner's competence and inter-organizational information systems (IOIS) as they are relevant when the complementary knowledge flows between organizations. The data required for this field study was collected from 70 buyers and their suppliers in three multinational enterprises in two different industries (Automobile manufacturing and Telecommunication services) headquartered in Korea. The results indicate that potential knowledge complementarities between buyer and supplier do not directly influence knowledge exchange, but indirectly through trust in partner's competence. And the results indicate that competence-based trust and IOIS have direct effects on knowledge exchange. Empirical results also show that IOIS moderates the relationship between potential knowledge complementarities and knowledge exchange. This study is a first attempt to empirically verify the theoretical model about potential knowledge complementarities and to investigate the impact of potential knowledge complementarities on interfirm knowledge exchange. From a theoretical perspective, this study not only clarifies the distinction between potential knowledge complementarities and implemented knowledge complementarities, but also develops an instrument to measure the concept of potential knowledge complementarities in the context of operational and planning knowledge in a supply chain. Further, we develop a theoretical framework suggesting that potential knowledge complementarities of partners in a supply chain affect knowledge exchange directly and indirectly through competence-based trust. The findings from this study have some managerial implications for practicing managers as well. First, buyers should search for suppliers that have potential complementary knowledge, which can be integrated to create synergy through interfirm knowledge exchange. Furthermore, firms must develop mechanisms to identify potential complementary knowledge of partners. Second, firms should continue their endeavor to develop their own unique knowledge so that their knowledge can benefit the entire supply channel. Finally, trust among supply chain partners turns out to be an important factor for interfirm knowledge exchange. Therefore, effective management for engendering trustworthy buyer-supplier relationships should receive appropriate attention from managers.

• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.4
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• pp.337-346
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• 2020

Traffic jam and congestion in urban areas has caused the need to improve the utility of underground space. In response, research on underground structures is increasingly being conducted. Notably, a double-deck tunnel is one of the most widely used of all those underground structures. This double-deck tunnel is separated by the middle slab into the upper and lower roadways. Both vehicle load and earthquake load cause the middle slab to exhibit dynamic behavior. Earthquake-related response characteristics, in particular, are highly complex and difficult to interpret in a theoretical context, and thus experimental research is required. The aim of the present study is to assess the stability of a double-deck tunnel's middle slab of the Collapse Prevention Level and Seismic Category 1 with regard to the presence of vibration-damping Rubber Bearings. In vibration table tests, the ratio of similitude was set to 1/4. Linings and vibrating platforms were fixed during scaled model tests to represent the integrated behavior of the ground and the applied models. In doing so, it was possible to minimize relative behavior. The standard TBM cross-section for the virtual double-deck tunnel was selected as a test subject. The level of ground motion exerted on the bedrock was set to 0.154 g (artificial seismic wave, Collapse Prevention Level and Seismic Category 1). A seismic wave with the maximum acceleration of 0.154 g was applied to the vibration table input (bedrock) to analyze resultant amplification in the models. As a result, the seismic stability of the middle slab was evaluated and analyzed with respect to the presence of vibration-damping rubber bearings. It was confirmed that the presence of vibration-damping rubber bearings improved its earthquake acceleration damping performance by up to 40%.

• The Journal of Society for e-Business Studies
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• v.14 no.4
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• pp.229-253
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• 2009

The effect of knowledge sharing and its importance have been reported in the information systems literature. However, little has been learned about the impact of knowledgeexchange web sites. This study explores relationships between individual characteristics such as personal innovativeness in the domain of information technology (PIIT), computer selfefficacy (CSE), and computer anxiety (CA), user involvement (UI), and knowledge sharing in a knowledge.exchange website. In order to examine our research model, we adopted a survey research design based on the Structural Equation Modeling method. By analyzing 241 samples collected, we conclude that UI and CA are valuable to discuss in terms of their theoretical and practical implications. This study not only extends the research on personal innovativeness and knowledge sharing, but also suggests a need for focused research efforts to investigate real practices on knowledge sharing. This study initiates this kind of efforts to make a relevant tie between design of knowledge sharing applications and the success case in the commercial field to encourage users to share their knowledge.

• Korean Security Journal
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• no.58
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• pp.215-241
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• 2019

This study approached the military security problem from the viewpoint of social psychology in view of the fact that the military security problem has been focused on the technical field such as cyber security along with the development of defense science and technology. In this background, we examined the causal relationship between variables after extracting variables affecting the security problem of the military through previous research. The significance of the study results is as follows. First, the military culture has a direct and indirect influence on improving the willingness to adhere to security and the security level of military organizations, as well as contributing to the establishment of military values. This indicates that the overall organizational culture of the current military is influencing the security consciousness of the soldiers and the achievement of organizational security, while at the same time showing the need for effort to create the right organizational culture. Second, the values of soldiers had a positive effect on the willingness of the individual to obey the security and the security performance. Values begin with an understanding of organizational culture and indicate that efforts can be made to establish an organizational security posture when the right values are formed. Third, we have improved the completeness of the study by verifying the causal relationship by extracting variables that correspond to the context of the ROK military.

• Journal of the Korea Convergence Society
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• v.9 no.9
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• pp.209-215
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• 2018

The purpose of this study is to grasp the overall policy decision system of sex crime prevention policy and analyze the interaction and pattern of actors in policy formation process. This is a useful way to identify the causes and ways to improve the policy if the sex crime prevention policy fails. As a research method, we used a model of advocacy through case analysis and language network analysis. In the external environment, low reporting of sex offenses, technical improvement and supplement for preventive management, consciousness of victims of sexual crimes, amendment of legislation, and support of the president. The conflicts between the advocacy coalition opposed the strong regulation, the prevention of recidivism, the expansion of the range of objects to be worn, the temporary effect of the system and the retrospective of the bill. As a problem-solving strategy, it was confirmed that the opposing positions of pros and cons of lack of manpower and negligence of management through the extension of the system were acutely opposed. In the context of media reports, this tendency is more likely to be understood as the concern of prevention and management at the central government level to prevent sex crimes. Therefore, although the methods of prevention of sex crimes have been insufficient in the past, it is hoped that this study will be helpful in breaking the link of negative policy vicious cycle.

• Journal of Korean Society for Geospatial Information Science
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• v.21 no.2
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• pp.27-34
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• 2013

Due to the increased interest in global warming, interest in forest resources aimed towards reducing greenhouse gases have subsequently increased. Thus far, data related to forest resources have been obtained, through the employment of aerial photographs or satellite images, by means of plotting. However, the use of imaging data is disadvantageous; merely, due to the fact that recorded measurements such as the height of trees, in dense forest areas, lack accuracy. Within such context, the authors of this study have presented a method of data processing in which an individual tree is isolated within forested areas through the use of LIDAR data and ortho-images. Such isolation resulted in the provision of more efficient and accurate data in regards to the height of trees. As for the data processing of LIDAR, the authors have generated a normalized digital surface model to extract tree points via local maxima filtering, and have additionally, with motives to extract forest areas, applied object oriented image classifications to the processing of data using ortho-images. The final tree point was then given a figure derived from the combination of LIDAR and ortho-images results. Based from an experiment conducted in the Yongin area, the authors have analyzed the merits and demerits of methods that either employ LIDAR data or ortho-images and have thereby obtained information of individual trees within forested areas by combining the two data; thus verifying the efficiency of the above presented method.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.530-540
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• 2020

Ecological momentary assessment (EMA) is a method that captures the current experience and behavior of subjects in real time in a natural environment. The data collected by EMA reveals alterations according to the time and context of experience and action. The Trier Inventory for Chronic Stress (TICS) is a tool that measures momentary stress, and is capable of measuring stress experienced in real life. This study was undertaken to verify the validity and reliability after translating the short form TICS into a Korean version. Totally, 89 police officers working at the police station in the capital participated in this study. The mobile application developed for this study was installed on their smartphones, and data were collected four times a day for seven consecutive days. Confirmatory factor analysis and content validity index (CVI) was applied to test the validity, and concurrent validity was evaluated by correlating with the occupational stress score. The model was validated by confirmatory factor analysis, and we obtained good reliabilities (I-CVI=0.83-1, RMSEA=0.104, SRMR=0.104, CFI=0.948, TLI=0.919, Cronbach's alpha=0.839). Our findings indicate the reliability, and validate use of the Korean tool for measuring momentary stress.

• Journal of Korean Library and Information Science Society
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• v.28
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• pp.447-475
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• 1998

We are seeing a shift of the focus of information service from system-centered(data-centered or intermediary-centered) a n.0, pproach to user-centered a n.0, pproach. Sense-making theory is one of the user- centered a n.0, pproaches. This study focused on user-centered information service paradigm concepts of Dervin's sense-making theory and interpreting sense-making theory in the practical context of library services. The sense-making theory is basically a cognitive a n.0, pproach to information-seeking, in that it recognizes information as something that involves internal cognitive processes. The user of information becomes the focus in this sense-making model. The sense-making theory sees information as subjective, situational, and cognitive. It focuses on understanding information within specific contexts and on understanding how information needs develop and how they are satisfied. It regards the user not as a passive receive of external information but as the center in a active, ongoing process of change. It related to the information needs of users. Dervin's method for studying information needs employs the 'situation-gap-use' metaphor. All information needs stem from a discontinuity or 'gap! in one's knowledge. Dervin believes that information needs can be addressed by understanding the process that each individual goes through in experiencing a gap, in trying to resolve it, and in gaining something (especially new knowledge) from the experience. Sense-making is a process; 'sense' is the product of this process. Sense includes 'knowledge'. However, it includes a host of other subjective factors that reflect an individual's interpretations of a situation including intuitions, opinions, hunches, effective responses, evaluations, questions, etc. For several reasons, however, difficulties are encountered if one attempts a more substantial assessment of the theory. First, it has not yet crystallized into a well-defined theory. Secondly, though the theory has aroused general interest, e.g. within LIS, detailed discussion of its strong and weak points is still lacking. A third source of difficulty is that the basic assumptions of the theory have been explicated metaphorically. If sense-making theory is to be really useful, it needs to be interpreted for library settings. But we have found no attempt to construct an information service based on the theory. Because the research tradition is still relatively young, there are many unanswered questions connected, e.g. with the design of information systems. In any case, e.g. intermediary access systems would be more efficient and effective it their planning could be founded on the user-centered a n.0, pproach.

• Journal of Nutrition and Health
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• v.40 no.sup
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• pp.29-38
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• 2007

The purpose of this study was to establish an association between the percent of energy from total sugar and disease prevalence of obesity, hypertension, dyslipidemia, insulin resistance, and metabolic syndrome with the context of the current population dietary practice in Korea. The Korean National Health and Nutrition Survey, 2001 and 2002 dataset were used as the source of data for this research. Usual nutritional intakes for over 20 years old people were calculated from the two non-consecutive dietary intake data from KNHANES 2001 and 2002 dataset. SAS and SUDAAN were used for statistical analyses. Sample weighted means, standard errors, and population percentages were calculated, and multiple logistic regression model with adjustment for covariates were used to determine the odds ratios(ORs) and 95% confidence intervals. Subjects were categorized as 3 ways and compared the LS means and ORs for heath factors. First, subjects excluding pregnant women, were categorized according to percent of energy from the usual total sugar intakes as ${\leq}10%$, 11-15%, 16-20%, 21-25%, >25%. Risk of LDL cholesterol showed a tendency to increase in the '>25%' group compared to the '<10%' group. The risks of the other health effects did not show any significant differences. Second, the subjects were categorized considering both Acceptable Macronutrient Distribution Range(AMDR) from carbohydrate and %Energy from total sugar as 'CHO<55% & Total sugar ${\leq}10%$', 'CHO 55-70% & Total sugar 11-25%', and '$CHO{\geq}70%$ & Total sugar ${\geq}25%$'. The risk of obesity tended to increase in the '$CHO{\geq}70%$ & Total sugar ${\geq}25%$' group compared to the 'CHO<55% & Total sugar ${\leq}10%$'. Third, the subjects were categorized as 'CHO<55% & Total sugar ${\leq}10%$', 'CHO 55-70% & Total sugar 11-20%', and '$CHO{\geq}70%$ & Total sugar ${\geq}20%$'. The risk of obesity also tended to increase in the '$CHO{\geq}70%$ & Total sugar ${\geq}20%$' group compared to the 'CHO<55% & Total sugar ${\geq}20%$' group. In conclusion, risk of LDL cholesterol showed a tendency to increase in the over 25% total sugar intake group, and the risk of obesity tended to increase in the 20-25% total sugar intake and high carbohydrate intake group. The risks of hypertension, hyperlipidemia, insulin resistance, and metabolic syndrome were not associated with total sugar intakes. More research to elucidate the association for Korean between the intakes of total sugar, added sugar, glucose, fructose, and sweeteners and diseases prevalences shoud be excuted in the future.