• Asia pacific journal of information systems
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• v.18 no.2
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• pp.73-94
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• 2008

When individuals collaborated in virtual settings, communication is medicated through a variety of communication technologies, and is associated not only with communication effectiveness but also with socio-emotional interactions among group members. In this regards, scholars have examined how technology-mediated communication systems can be designed and used to facilitated communication interaction. However, the empirical results of the previous studies have revealed inconsistencies in the effects of communication media on users' behavioral or attitudinal responses, and on their viable effectiveness in organizations. Some studies claim that computer-mediated communication(CMC) is task-oriented but not suitable for emotional expression since it hinders close interpersonal interaction. On the other hand, some studies argue that individuals are able to develop interpersonal relationships more effectively in a CMC environment than in an FtF-environment. Due to the different perspectives, a theoretical gap exists, and it leads to the inconsistent research findings. The purpose of this paper is to combine the two different perspectives into single unified model, thereby providing a more realistic and comprehensive understanding about virtual collaboration. The present study here sought to answers the following questions with organizational communication perspective: What are the major components of virtual collaboration? What factors affect the performance of virtual collaboration? And what kind of managerial efforts should organization make in order to facilitate CMC media effectiveness in virtual collaboration? Although there is a certain belief that new media, namely technology-mediated communication support would create new opportunities, the problem of "how" or "why" has been an important question that is still not fully addressed. In this regards, we collectively reexamined previous literatures with major issues which are still controversial and integrated various theoretical activity within computer-mediated communication domain: task-oriented approach, socio-emotional approach, and evolutionary psychological approach. Our first contribution is to develop a framework for virtual collaboration by combining two different perspectives into a single unified model, providing a more realistic and comprehensive understanding. The second main contribution is the joint modeling of both social presence and cognitive effort, and the effects on two distinct but important communication outcomes(i.e., take performance and relational development). We tested the research hypotheses which were developed based on the various CMC theories using data gathered through a self-administered mail survey of 127 individuals of 69 virtual workgroups. The proposed model was supported, providing preliminary evidence that the tension between two opposite view should be integrated. The results show that the individual's psychological processes(social presence and cognitive effort) in a virtual environment significantly mediated the effect of CMC inputs (media richness, user adaptation, and shared contest) on the CMC outputs (task performance and relational development). Furthermore, this study shows that the lack of perceived media richness of CMC media can be complemented by user adaptation and shared context. Based on the results, we discuss how communication system should be designed and implemented so as to promote virtual interaction as well as how a virtual workgroup should be composed to complement the lack of media richness. A virtual collaboration using CMC media may create new value by overcoming the logistical constraints. On the other hand, it may also generate various managerial risks such as communicational depersonalization, process dissatisfaction, and low cohesion. Therefore, this study suggests that organization managers should carefully choose the CMC mediums and monitor individual member's cognitive and affective psychological processes during virtual collaboration to reduce potential risks in virtual collaboration.

• Food Science of Animal Resources
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• v.28 no.3
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• pp.373-389
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• 2008

This study was conducted to evaluate exposure level and risk of heavy metals in livestock foodstuffs and Korean foods. Based on the "Food Intake Data," a part of the 2005 National Health & Nutrition Survey and the "2005 Seasonal Nutrition Survey", 113 Korean foods items were selected. 3 samples from different manufacturers of each 113 items of Korean foods were purchased on summer and fall, so total 678 samples were used. The food groups were classified into 15 categories. For the livestock foodstuffs category, meats and poultry (chicken, pork, pork belly, beef, beef feet soup), milks and dairy products (milk, ice cream, liquid yoghourt, sherbet), eggs (egg) were selected. It was found that the daily amount of heavy metals intake (mg/person/day) from livestock foodstuffs is 0.00020 arsenic, 0.00000 cadmium, 0.00020 lead, and 0.00006 mercury, and the daily amount of heavy metals intake (mg/person/day) from Korean foods is 0.0265 arsenic, 0.0083 cadmium, 0.0067 lead, and 0.0028 mercury. Daily amount of heavy metals intake from livestock foodstuffs was low among the food groups. For risk assessment, PDI (Probable Daily Intake) was calculated and compared with PTWI (Provisional Tolerable Weekly Intake) of JECFA (Joint FAO/WHO Expert Committee on Food Additive). Relative hazard of these livestock foodstuffs was 0.006% in arsenic, 0.000% in cadmium, 0.085% in lead, and 0.149% in mercury. Relative hazard of Korean foods was 0.941% in arsenic, 14.676% in cadmium, 3.319% in lead, and 6.860% in mercury. Thus, livestock foodstuffs and Korean foods were as safe as satisfied with the recommended standards of JECFA.

• Wind and Structures
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• v.31 no.2
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• pp.103-142
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• 2020

One of the next frontiers in structural wind engineering is the design of tall buildings using performance-based approaches. Currently, tall buildings are being designed using provisions in the building codes and standards to meet an acceptable level of public safety and serviceability. However, recent studies in wind and earthquake engineering have highlighted the conceptual and practical limitations of the code-oriented design methods. Performance-based wind design (PBWD) is the logical extension of the current wind design approaches to overcome these limitations. Towards the development of PBWD, in this paper, we systematically review the advances made in this field, highlight the research gaps, and provide a basis for future research. Initially, the anatomy of the Wind Loading Chain is presented, in which emphasis was given to the early works of Alan G. Davenport. Next, the current state of practice to design tall buildings for wind load is presented, and its limitations are highlighted. Following this, we critically review the state of development of PBWD. Our review on PBWD covers the existing design frameworks and studies conducted on the nonlinear response of structures under wind loads. Thereafter, to provide a basis for future research, the nonlinear response of simple yielding systems under long-duration turbulent wind loads is studied in two phases. The first phase investigates the issue of damage accumulation in conventional structural systems characterized by elastic-plastic, bilinear, pinching, degrading, and deteriorating hysteretic models. The second phase introduces methods to develop new performance objectives for PBWD based on joint peak and residual deformation demands. In this context, the utility of multi-variate demand modeling using copulas and kernel density estimation techniques is presented. This paper also presents joined fragility curves based on the results of incremental dynamic analysis. Subsequently, the efficiency of tuned mass dampers and self-centering systems in controlling the accumulation of damage in wind-excited structural systems are investigated. The role and the need for explicit modeling of uncertainties in PBWD are also discussed with a case study example. Lastly, two unified PBWD frameworks are proposed by adapting and revisiting the Wind Loading Chain. This paper concludes with a summary and a proposal for future research.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.9
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• pp.4217-4222
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• 2016

Purpose: To compare the expression level of CK 15 in normal esophageal and esophageal squamous-cell carcinoma (ESCC) tissues and analyse possible functions of CK15 in occurrence and development. Materials and Methods: Immunohistochemistry was used to compare CK14, CK15 and proliferating cell nuclear antigen (PCNA) expression levels in ESCCs. Expression level of CK15 was also assessed by Western blotting. In addition, levels of CK15, cytokeratin 19 fragment antigen 21-1 (CYFRA21-1) and PCNA were detected in serum by enzymelinked immunosorbent assay (ELISA) and chemiluminescence methods. Relationships between clinicopathological parameters and CK14 and CK15 expression were then analyzed. Results: According to immunohistochemistry, in esophageal and intraepithelial neoplasia (SIN) tissues, the expression of CK14, CK15 and PCNA localized to basal layer of the epithelium. CK14 and CK15 levels were higher in normal esophageal squamous epithelial tissue than in SIN and ESCC, and greater in highly differentiated than poorly differentiated carcinoma tissue. By Western blotting, we found more pronounced expression of CK15 in normal esophageal tissue, compared with carcinoma tissue. The specificity of changed CK15 and CYFRA21-1 expression was respectively 90.0% and 96.7% in serum of ESCC patients. Joint detection could improve the sensitivity of esophageal carcinoma diagnosis. Relationships between CK14, CK15 expression and clinical parameters were not statistically significant (P>0.05). Postoperative survival in patients of CK14, CK15 positive expression was longer than with negative expression ($x^2=4.35$, P=0.037; $x^2=9.852$, P=0.002). Conclusions: CK15 expression decreased in esophageal squamous cell carcinoma tissue and serum of esophageal squamous carcinoma patients. We infer that CK15 may play an important role for the occurrence and development of esophageal squamous-cell carcinoma. In the future, CK15 may be used for the diagnosis, treatment and prognostic evaluation of esophageal squamous-cell carcinoma.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.6
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• pp.617-624
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• 2015

This paper describes the development of a wearable robot to assist the elbow muscle for use by elderly workers in aging societies. Various previously developed wearable robots have drawbacks in terms of their price, portability, and slow recognition of the wearer's intention. In this paper, emphasis is placed on the following features to minimize these drawbacks. The first feature is that an actuator is attached only at the elbow joint that withstands the highest moment during arm motion to reduce the weight, volume, and price of the robot and increase its practicality. The second is that operation of the wearable robot is divided into two modes, a tracking mode and a muscle strengthening mode, and the robot can automatically switch between these modes by analyzing the wearer's intention through the brachial muscle strength measuring device developed in this study. The assistive performance of the developed wearable robot is experimentally verified by motion tracking experiments without an external load and muscle strengthening experiments with an external load. During the muscle strengthening experiments, the power of the muscle of the upper arm is measured by a commercial electromyography (EMG) sensor. Motion tracking performance at a speed of $120^{\circ}/s$ and muscle assistance of over 60 % were obtained using our robot.

• Journal of Global Scholars of Marketing Science
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• v.18 no.4
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• pp.277-306
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• 2008

Knowledge1 is considered to be a key element of understanding how organizations gain and sustain competitive advantages. But very few firms are capable of creating the requisite knowledge and thus, firms should acquire and exploit new knowledge through knowledge transfer processes. The empirical part of this study involves examining relationships among adaptability of knowledge and knowledge transfer and marketing performance and testing the moderating roles of absorptive capacity, socialization and local marketing knowledge. This study is organized as follows: (1) Previous literature on knowledge, knowledge transfer and absorptive capacity is summarized, followed by the development of hypotheses derived from the knowledge-based view and absorptive capacity. (2) The hypotheses are tested with data collected from MNCs' subsidiaries performing marketing activities in Korea.Thestudyisclosedwithfindings,implications,andconclusions. Following six research hypotheses are drawn from literature review in related areas: H1: Adaptability of knowledge transferred from the MNCs' headquarters and other subsidiaries is positively associated with knowledge inflows into the receiving subsidiary. H2: The level of marketing knowledge transferred from the MNCs' headquarters and other subsidiaries is positively associated with marketing performance of the receiving subsidiary. H3: Increases in potential absorptive capacity will enhance the relationship between adaptability of knowledge and the level of marketing knowledge transfer. H4: Increases in realized absorptive capacity will enhance the relationship between the level of knowledge transfer and marketing performance of the receiving subsidiary. H5: Increases in socialization activity among the headquarters and subsidiaries will enhance the relationship between adaptability of knowledge and the level of marketing knowledge transfer. H6: Increases in the level of locally developed marketing knowledge will enhance the relationship between the level of knowledge transfer and marketing performance of the receiving subsidiary. The research framework that illustrates the proposed hypotheses is presented in figure 1. The unit of analysis for this study is knowledge transfer from the MNCs' headquarters and other subsidiaries to their subsidiaries operating in South Korea. The population for this study consists of subsidiaries established either as joint ventures or as wholly-owned subsidiaries. A group of 603 foreign firms were drawn from diverse industry organizations and business societies. After personal contact, telephone, fax, and e-mail to request that the respondents complete the questionnaire, 282 valid questionnaires from 133 initial sample companies were collected. The results of the empirical analyses significantly support all of the proposed hypotheses except hypothesis 3. Adaptability of external knowledge promotes knowledge transfer and the relationship is moderated by a firm's potential knowledge absorptive capacity. On the other hand, knowledge transfer improves a firm's marketing performance and a firm's realized knowledge absorptive capacity and local marketing knowledge moderate the relationship. The theoretical and practical implications of the findings in this study are as follows: (1) firms must take seeking, transferring, sharing and exploiting of external knowledge into serious consideration, while simultaneously creating knowledge to support the necessary business operations, remain competitive, and achieve superior performance. (2) Firms should continuously seek to develop their knowledge absorptive capacity (both potential and realized capacity) to absorb, learn and utilize valuable external knowledge. (3) Firms should emphasize not only absorptive capacity, but also development of local knowledge. Firms with strong absorptive capability and local knowledge can learn and transfer more external knowledge, which can be translated into greater levels of competence and performance.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.27 no.2
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• pp.281-292
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• 2017

It is demanded to promote research and development of cyber weapons system and core technology in response to the ongoing cyber attack of North Korea. In this paper, core technologies of the future cyber weapon system are developed and the factors affecting the realization timing of core technologies were analyzed. 9 core technology groups and 36 core technologies are derived. Afterwards, these core technology groups are compared to the operation phase of the joint cyber warfare guideline and the cyber kill chain of Lockheed Martin. As a result of the comparison, it is confirmed that the core technology groups cover all phases of the aforementioned tactics. The results of regression analyses performed on the degree of influence by each factor regarding the moment of core technology realization show that the moment of core technology realization approaches more quickly as factors such as technology level of the most advanced country, technology level of South Korea, technology transfer possibility from the military sector to the non-military sector(spin-off factor), and technology transfer possibility from the non-military sector to the military sector(spin-on factor) increase. On the contrary, the moment of core technology realization is delayed as the degree at which the advanced countries keep their core technologies from transferring decrease. The results also confirm that the moment of core technology realization is not significantly correlated to the economic ripple effect factor. This study is meaningful in that it extract core technologies of cyber weapon system in accordance with revision of force development directive and join cyber warfare guideline, which incorporated cyber weapon system into formal weapon system. Furthermore, the study is significant because it indicates the influential factor of the moment of core technology realization.

• The Korean Journal of Quaternary Research
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• v.3 no.1
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• pp.87-101
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• 1989

The development of the Hantan river basin can be divided into three stages. The first stage include the ancient Hantan channel system prior to the Chongokni basalt which yield dates of about 0.6 mya from the K/Ar dating method. During this period the Baekuyri formation was formed. The Baekuyri formation is widely observed under the Chongokni basalt along the current river system. The second stage is the period when stream channels stayed on the top of the basalt plateau. Aggradation and deggradation were continued by meandering and braiding channel systems until major stream channel was formed. The currently remaining deposit on the top of the basalt was formed by lacustrine and fluvial systems in this period. During this period Pleistocene hominid was present on edge of water and flood plain and left Paleolithic material. This period was begun at the time of the final basalt flow dated about 300,000 BP. The third stage is designed for the time when the Hantan river channel was dropped down to a level from which the channel could not influence the top of the basalt any more No more deposit could be formed but erosion by surface water has been continued on the top of the basalt since then. The dropping of the Hantan river channel was probably not very long after the final flow of the basalt. Because of frost action and heavy concentrated precipitation in the basin area along with blocky and clumnar joint structure of the basalt, erosional process of the basalt is believed to have been carried out within a relatively short time. The lowering of the Hantan river channel was probably completed in a cycle of major fluctuation of world cimate. Also, the redclay on the top of the basalt is believed to have been formed during a warm period around 200,000 BP, which accords with the climatic change suggested above fair1y well. The Paleolithic materials in tile deposits fell accordingly into approximately same time period.

• The Korean Journal of Community Living Science
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• v.25 no.1
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• pp.99-111
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• 2014

To verify welfare needs, rural health and environmental factors were compared between agricultural and nonagricultural groups over the past 10 years. Based on a survey of rural life by the Rural Development Administration, whose sample included agricultural (72.8%) and nonagricultural (27.2%) groups, all factors were analyzed using SAS ( 9.3). For rural home heating, the use of oil boilers (77.2%-78.0%) decreased (53.0%-53.7%) over the same period, whereas that of electric boilers increased (21.9% and 13.5% for agricultural and nonagricultural groups, respectively). The joint water- supply increased, and the use of flush toilets (52.4% to 84.5% in the agricultural group and 64.6% to 81.4% in the nonagricultural group) and hot-water bathing was higher in the agricultural group (79% to 92.6%) than in the nonagricultural group (72.2% to 87.6%) at the p<0.001 level. Incineration accounted for the largest portion of household waste until 2006, when it was replaced by other treatment methods such as the pay-per-treatment option (44.4% and 68.3% in the agricultural and nonagricultural groups, respectively) (p<0.001). Garbage disposal in 2001 was mainly burial or animal feed, but separate collection increased in 2010 (42.2% and 64.3% in the agricultural and nonagricultural groups, respectively) (p<0.001). The self-perception of health was lower in the agricultural group than in the nonagricultural group (2.96 to 2.74 on a five-point scale in the agricultural group and 3.07 to 2.98 in the nonagricultural group). Drinking decreased less in the agricultural group (criteria: one point once a week,; 1.48 to 1.20) than in the nonagricultural group (1.13 to 0.80) at p<0.001, and a similar pattern was found for smoking (p<0.001). Health screening decreased in the last 10 years (scoring based one point/1-2 times per year,: 0.94 to 0.64 in the agricultural group and 1.08 to 0.69 in the nonagricultural group;p<0.01). These results indicate that various health and environmental factors were less favorable to farmers except for bathing in comparison to nonagricultural living in the same area. This suggests that people in agriculture are less likely to live and work in favorable environments than those outside the sector and thus indicates a need for more attention to the national health welfare system for farmers for systematic realization.

• Journal of Society of Preventive Korean Medicine
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• v.9 no.2
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• pp.77-91
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• 2005

The purpose of this study is to examine the recognition of the student of oriental medical school on cooperative system between Oriental and Western medicine and to provide basic information for the development of oriental medicine. In order to look at the level of recognition on cooperative system between Oriental and Western medicine, from September 1st to 15th of 2005, this study had been conducted through personal interview and questionnaires to 600 students who were attending the Department of Oriental Medicine (in both prep and regular courses) in D University, located in the City of Daegu. The data has been analyzed using statistic program, the SPSS WIN 12.0. Statistical analysis tools used for this study were frequency analysis, cross-over analysis and the t-test. The results are as follows; The students of oriental medical school had relatively high level of recognition on the basic concept, interests, necessity and potential for cooperative system between Oriental and Western medicine. However, they had negative understandings on the issue of unification of the two medical systems and it's possibility in the future. The students were optimistic about possible merits of cooperative system between Oriental and Western medicine, especially in the field of rehabilitation. On the reasons for lack of development of cooperative system between Oriental and Western medicine, the students listed prejudices existing on both sides firstly, followed by their contrasting approach on human illness, lack of legal and institutional support system, the indifferences of doctors and indifferences of oriental medical doctors. In addition, students understood that the dualism existing in our current medical system is aggravating mutual distrust between the two sides, causing the confusion of patients on the choice of medical facilities, and raising their medical bills. Therefore, in order to vitalize collaboration between Oriental and Western medicine in new health care environment, the following measures should be needed decreasing the prejudices between the two medical spheres with open mind improving educational programs in Western and Oriental medical schools; promoting joint academic research or exchange programs between the schools, and increasing government effort to minimize legal and institutional restrictions cooperative system between Oriental and Western medicine.