• Title/Summary/Keyword: Research approach

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Development of an Approach for Analysing Vegetation Community Mosaic Using Landscape Metrics (경관지수를 활용한 식생군락 모자이크화 분석법)

  • Lee, Peter Sang-Hoon;Jeong, Jong-Chul
    • Journal of Cadastre & Land InformatiX
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    • v.47 no.1
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    • pp.161-178
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    • 2017
  • Whereas the demand for development of forested areas covering more than 60% of Korean territory, permission on the forest development has been still given from the perspective of effective land utilization rather than conservation. As the assessment of large forested areas usually focuses more on forest structure, it has its limitation of observing and analyzing the interior change in forest in this way. This study was aimed at computing landscape metrics using a presence vegetation map and FRAGTSTATS 4.2 and analyzing vegetation mosaics. Colonies in native vegetation were classified into a series of major groups and sub-groups based on the native species within the colonies. The colonies were investigated by analyzing a suite of landscape metrics - Core Area, Percentage of Landscape, Number of Patches, Patch Density, Largest Patch Index, Total Edge, Edge Density, Landscape Shape Index, Mean Patch Area, Euclidean Nearest Neighbor. In the Chungnam province major groups and sub-groups of colonies classified based on the proportion of pine and oak species, and pine species was the principal one in terms of distribution area. As for the competition between pines and oaks, while the coverage of pine-centered colonies were three times larger than those of oak-centered ones, pine colonies showed the greater number of patches and therefore higher fragmentation than oaks at the major group level. For the sub-groups, the largest coverage colonies were not only indicated by Pinus densiflora-Quesrcus mongolica colonies among P. densiflora-centered colonies, Q. accutissima colonies among Q. accutissima-centered ones, Q. accutissima-P. densiflora colonies among Q. accutissima-centered ones, Q. mongolica colonies among Q. mongolica-centered ones, P. thumbergii colonies among P. thumbergii-centered ones, and Q. serrata-Q. acutissima colonies among Q. serrata-centered ones, but also revealed more severely mosaicked than other smaller colonies. The overall mosaicking degree estimated by landscape metrics was considered useful for monitoring and investigating vegetation. However, in order to develop management strategy based on analyzing the reason for the mosaicking process and anticipating a trend in vegetation succession, it is essential to further study about ecological characteristics of each colony in the vegetation.

The Effect of Hotel Employee's Service Orientation on Service Performance, Job Satisfaction, and Organizational Commitment (호텔기업 종업원의 서비스지향성이 서비스 성과, 직무만족과 조직몰입에 미치는 영향)

  • Park, Dae-Hwan
    • Journal of Global Scholars of Marketing Science
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    • v.17 no.4
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    • pp.1-22
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    • 2007
  • Customer satisfaction is important in an increasingly competitive and global marketplace. This implies that customer service is a critical factor for many organizations. In service encounter context, customer satisfaction is affected by employees' attitudes and behaviors. Accordingly, service firms have been focusing on selecting high quality of service employees, which resulted the ability to identify and select quality service- or customer- oriented employees to become critical for an organization's success. It was suggested that customer service orientation links to performance and subsequent organizational revenue. Moreover, it was found that service encounter failures were among the major reasons for customers' service switch. Therefore, the selection of customer service oriented employees is a key factor in establishing customer service - a potential source of sustained competitive advantage. However, the measurement of employee service orientation is more confusing than that of definitive answers. The difficulty of measuring service orientation is attributed to the use of broad versus narrow measures of personality. Advocates for the broad perspective prefer using basic personality constructs, such as the Big Five personality traits. On the contrary, the latter prefer a construct-oriented approach of personality research that provides a better measure of job performance because it requires the specification of the relationship of the personality traits with multiple dimensions of job performance. The customer service orientation was defined as "a set of basic individual predispositions and an inclination to provide service, to be courteous and to be helpful in dealing with customers and associates." Similarly, it is a fact that the Big five personality traits are predictors of customer orientation, and employee's self- and supervisor performance. They propose that basic personality traits may be too far removed from focal service behaviors to be able to predict specific service behaviors (customer orientation) and service worker performance. Also, customer orientation is defined as "an employee's tendency or predisposition to meet customer needs in an on-the-job context." This means that people who have job-relevant personality traits such as concern, empathy, and conscientiousness will be more adept at customer service than people who do not possess these traits. However, little attention has been given to the exploration of the service orientation of customer-contact employees who play a key role in creating satisfactory service encounters in the hospitality industry except for Kim, McCahon, & Miller (2003)'s study, especially in family restaurants context. Thus, the purposes of this study are to examine and validate the customer service orientation of customer-contact employees using the instrument developed by Donavan (1999) in Korean family restaurants, because the scale was developed to measure the personality traits related job behaviors. And this study explores the relationships between customer service orientation, job satisfaction, organizational commitment, and self service performance using structural equation modeling (SEM). And this study explores the relationships between customer service orientation, job satisfaction, organizational commitment, and self service performance using structural equation modeling (SEM). For these purposes the author developed several hypotheses as follows: H1: Employee's service orientation is associated with service performance. H2: Employee's service orientation is positively associated with job satisfaction. H3: Employee's service orientation is positively associated with organizational commitment. H4: Service performance is positively associated with job satisfaction. H5: Service performance is positively associated with organizational commitment. H6: Job satisfaction is negatively associated with organizational commitment. The data were collected from 278 employees in 5 deluxe hotels located in Pusan, Korea. The researcher contacted the manager of the restaurants, and managers consented to administer surveys to their employees. The survey was executed during one month period in the October of 2007. The data were analyzed with structural equation modeling with LISREL 8.7 W. The result of the overall model analysis appeared as follows: $X^2$=122.638 (p = 0.00), df=59, GFI=.936, AGFI=.901, NFI=.948, CFI=.971, RMSEA=.0625. Since the result of the overall model analysis demonstrated a good fit, we could further analyze our data. The findings can be summarized as follows: First, the greater the employee service orientation, the greater the service performance. Second, the greater the employee service orientation, the greater the job satisfaction. Third, the greater the employee service orientation, the greater the organizational commitment. Fourth, the greater the service performance, the greater the job satisfaction. Fifth, the greater the service performance, the greater the organizational commitment. Finally, the greater the job satisfaction, the greater the organizational commitment. Seventh, the greater the customer satisfaction, the greater the customer loyalty.

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Characterization of Bovine Lymphocyte Antigen DRB3 exon2 Gene of Korean Native Cattle (한우의 BoLA DRB3 exon2 유전자의 특성)

  • Kang, Ho Bum;Ryoo, Seung Heui;Lee, Sang Hoon;Jeon, Byung Soon;Sang, Byung Chan
    • Korean Journal of Agricultural Science
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    • v.25 no.1
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    • pp.79-88
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    • 1998
  • This study was performed in order to apply to effective breeding of Korean native cattle on the molecular genetic level obtained from PCR and nucleotide sequencing analysis of BoLA DRB3 exon2 that has important roles in host immune defence. Genomic DNA used in this study was prepared from the blood of Korean native cattle in Korean Native Cattle Improvement Center of National Livestock Cooperation. The results obtained from this study are summarized as follows: 1. Genomic DNA extracted from the blood of Korean native cattle was subjected to electrophoresis on 1.5% agarose gel. Major band was bigger than 12.2kb, indicating that genomic DNA was well prepared for PCR. Amplified products of 284bp fragments was obtained the amplification of BoLA DRB3 exon2 gene by PCR. 2. Cloning of BoLA DRB3 exon2 of Korean native cattle with pCR2.1 vector was conformed by 300bp fragment from recombinent plasmid that restricted with enzyme digestion of EcoRI. 3. Homology of BoLA DRB3 exon2 alleles of parent was 82.0% between sire's alleles and 90.1% between dam's alleles. 4. In pedigree analysis using BoLA DRB3 exon2 gene, sequencing result of BoLA DRB3 exon2 genes showed inheritance by Mendelian mode through the parents to their offspring. 5. Taking together those experimental results, pedigree was confirmed on the basis of sequencing for the alleles of parents and offspring. This knowledge by the molecular biological approach could be served for the improvement of Korean native cattle.

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Stabilization and Release Behavior of W1/O/W2-Type Multiple Emulsions Using Various Block Copolymer Emulsifier and Stabilizer (다양한 Block Copolymer를 유화제 및 안정화제로 사용한 W1/O/W2-Type 다중에멀젼의 방출거동 및 안정성)

  • Haw, Jung-Rim;Kim, Cheol-Hun
    • Applied Chemistry for Engineering
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    • v.8 no.4
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    • pp.560-567
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    • 1997
  • A new approach to obtain stable $W_1/O/W_2$ multiple emulsions has been studied ; The basis of the interfacial interaction between a PCL-PEO-PCL triblock copolymer and a lipophilic emulsifier in the dispersed oil phase was examined. $W_1/O/W_2$ multiple emulsions were prepared by the two-step method. Arlacel P-l35 was used as a liphophilic emulsifier and Synperonic PE/F 127 as a hydrophilic one. Eutanol-G was used as an oil phase. NaCl was encapsulated within the multiple emulsion droplets as the internal marker and its release rate studies were carried out. The suability of the multiple emulsions have been assessed by measuring Separation Ratios(%) and microscopic observations. The release of NaCl was significantly reduced in $W_1/O/W_2$ multiple emulsions containing PCL-PEO-PCL triblock copolymer(2k-4k-2k or 6k-4k-6k) in the oil phase. It may be concluded that the copolymer and the emulsifier form effective interfacial complex to enhance stability and to control the release rate. The effective diffusion coefficients of the NaCl were estimated as $2.64{\times}10^{-15}s$and $3.23{\times}10^{-16}gcm^2/s$ for the $W_1/O/W_2$ multiple emulsion containing 1.2 wt % of PCL-PEO-PCL triblock copolymers with compositions of 2k-4k-2k and 6k-4k-2k, respectively. The rate of release decreased with the increase of the initial concentration of NaCl. The results were examined in view of Higuchi mechanism. A kinetic model which is similar to the model for release of dispersed drugs from a polymeric matrix was found to be suitable for the release of NaCl from $W_1/O/W_2$ multiple emulsions.

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A Study on the Consumer's Service Quality Perception Based on the Types of Life-style (소비자의 라이프스타일에 따른 서비스품질 지각 차이에 관한 연구)

  • Park, Yoon-Seo;Lee, Seung-In;Choi, In
    • Journal of Global Scholars of Marketing Science
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    • v.19 no.2
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    • pp.53-67
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    • 2009
  • For the last decades, service quality has been studied as one of the most important tools for a service company to compete with the other companies. Based on these past researches, it has been agreed that the service quality is a basic and powerful tool to create the competitive advantage. Due to similar reason, many service marketing practitioners have been also focused on the service quality to retain the existing consumers and collect the new consumers. However, service quality is subjectively perceived by individual consumers. Consumer evaluation of service quality can be different from each other. Especially consumers with one life-style may evaluate the service quality differently from the consumers with the other life-styles. Therefore we need to know whether there are differences in service quality perception on the categories of life-style. Life-style refers to a distinctive mode of living in its aggregate and broadest sense. It embodies the patterns that were developed and emerged from the dynamics of living in a society. Since the concept of life-style and its relationship to marketing was introduced in 1963 by William Lazer, methods of measuring the life-style and their application have been developed. Life-style has been usually used to segment the marketplace because it offers marketers a unique and important view of the market. When Life-style is combined with clustering methods, life-style segmentation can generate identifiable whole persons rather than isolated fragment. Life-style segmentation begins with people instead of products and classifies them into different life-style types, each characterized by a unique style of living based on a wide range of activities, interests, and opinions(Plummer, 1974). In this study we applies the life-style segmentation based on the AIO(Activities, Interests, and Opinions) to the consumers of the large discount stores. In Korea, the large discount store market has entered into maturity stage so that the market differentiation strategy is becoming a more critical issue to the marketing practitioners. One of the most important tools to differentiate from the competitors in large discount store market is continuously to provide service of better quality than competitors. This study tries to find answers about the following questions: 1) How can we categorize the consumer life-styles in the large discount store? 2) What are the characteristics of the categorized groups? 3) Are there any differences in service quality perception among the consumers with different life-styles 4) Are there any differences in consumer behavior among them in the large discount store? For the purpose, we collected survey data from consumers and analyzed the data with the SPSS package where we had $X^2$-test, factor analysis, ANOVA, MANOVA, and cluster analysis. The survey was made during one month in the April of 2008. Among the collected 306 copies of questionnaires, 281 copies were chosen as the effective samples for empirical analysis except 25 copies with wrong responses. To identify the life-style patterns, we used the measures employed by Kim and Kwon(1999), where 44 items on a seven-point scale were used to measure factors of the life-style patterns. The Principal Component Method was used for factor extraction, and the VARIMAX orthogonal factor rotation was employed. The 7 items showing low factor loading were eliminated. The results of the factor analysis suggested that nine factors of the life-style patterns were identified as follows: 1) the equality-of-sexes and pursuit-of-independence tendency 2) self-management tendency 3) sociable tendency 4) self-display tendency 5) degree of a dilettante life 6) pursuit-of-information tendency 7) bargain hunter tendency 8) TV preference tendency 9) pursuit-of-leisure tendency. Next, after the K-means cluster analysis was performed with nine factors of the life-style patterns, the life-styles of the respondents were classified into four groups which are named as the 'progressive practicality-oriented group', 'positive success-oriented group', 'sociable ostentation-oriented group', 'stable conservation-oriented group'. The analysis results for usage behavior between the market segments showed statistically significant differences in the frequency of usage, duration time in the store, consumer satisfaction, and loyalty. Also, we tried to investigate whether the large discount store consumers differently perceive the quality of service based upon the types of life-style. To measure the service quality of large discount store, we adapted several measurement models measuring the service quality such as SERVPERF, BCP, R-SERVPERF, R-BCP. MANOVA and One-Way ANOVA were performed to confirm the difference in service quality perception based on the market segments. The results have also shown significant differences between life-style types in service quality perception. These findings show that the large discount store marketers should consider consumer life-style as one of the most important market segments for marketing and understand the difference in service quality perception between life-style types. Our findings give important implications to marketers of large discount stores as well as life-style researchers. First, this study showed there were significant differences in consumer's service quality perception and usage behavior between the types of life-style. It provides evidence that the life-style approach can be a important basis in segmenting the large discount store market and will make consumers perceive the service quality high. Second, most previous researches on service quality have been in aggregate level. However, our results imply that the future research on service quality have to focus on segment level.

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An Approach to Enhance the Unfair Area in the Rural Landscape (농촌 조건불리지역의 경관개선을 위한 접근)

  • Jang, Gab-Sue;Park, In-Hwan
    • Journal of the Korean Institute of Landscape Architecture
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    • v.36 no.2
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    • pp.60-68
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    • 2008
  • Three land-use limitations including water hazard, soil erosion and fallow potential were evaluated to define an unfair area. Landscape indices in the unfair areas, defined by evaluations before and after landscape enhancement, were computed by Fragstats v3.3 and compared in order to propose a landscape enhancement plan. The results are as follows: First, as a result of the land evaluation, 388.56ha was analyzed for the 1st class(S1), 623.25ha for the 2nd class(S2), 138.08ha(S3s: 82.47ha, S3e: 51.88ha) for the 3rd class(S3), 230.44ha(N1w: 194.91ha, N1e: 23.09ha, N1es: 13.94ha) for the 4th class(N1), and 67.91ha(N2w: 60. 89ha, N2es: 7.02ha) for the 5th class(N2). The classes under the 3rd class(including the 3rd class) were determined as an unfair area, and proposed landscape enhancement for them. Second, it was proposed that unfair areas with potential water hazards(N1 w, N2w) be restored as a wetland and buffer zone. At this point, the farmers owning these fields could be compensated using the direct payment for landscape conservation(DPLC). Areas witha relatively lower slope(S3e) or a steep slope(N1e) containing soil erodibility potential were proposed to be restored as a sod-culture-applied field and substitute vegetation or potentially natural vegetation, respectively. The unfair areas having fallow potential(S3s, N1es, N2es) were proposed to apply special use crops for the S3s fields, native plants for the N1es fields, and intended fallow for the N2es fields. Third, after landscape enhancement, theforest had higher values in the indices of NP, PLAND, LSI, IJI, and TCA, while paddy and upland had lower values in most indices except NP and LSI. The forest patches increased and were more plentiful with their restoration and had much greater possibility to join with nearby patches. With continued restoration, forest patches will have a large core area and small number of patches due to the conglomeration of patches, which positively influences the species of diversity in the forest patches.

Estimate and Environmental Assessment of Greenhouse Gas(GHG) Emissions and Sludge Emissions in Wastewater Treatment Processes for Climate Change (기후변화를 고려한 하수처리공법별 온실가스 및 슬러지 배출량 산정 및 환경성 평가)

  • Oh, Tae-Seok;Kim, Min-Jeong;Lim, Jung-Jin;Kim, Yong-Su;Yoo, Chang-Kyoo
    • Korean Chemical Engineering Research
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    • v.49 no.2
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    • pp.187-194
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    • 2011
  • In compliance with an international law about the ocean dumping of the sludge, the proper sewage treatment process which occurs from the wastewater treatment process has been becoming problem. Generally the sewage and the sludge are controlled from anaerobic condition when the sewage is treated and land filled, where the methane$(CH_{4})$ and the nitrous oxide $(N_{2}O)$ from this process are discharged. Because these gases have been known as one of the responsible gases for global warming, the wastewater treatment process is become known as emission sources of green house gases(GHG). This study is to suggest a new approach of estimate and environmental assessment of greenhouse gas emissions and sludge emissions from wastewater treatment processes. It was carried out by calculating the total amounts of GHG emitted from biological wastewater treatment process and the amount of the sludgegenerated from the processes. Four major biological wastewater treatment processes which are Anaerobic/Anoxic/Oxidation$(A_{2}O)$, Bardenpho, Virginia Initiative Plant(VIP), University of Cape Town(UCT)are used and GPS-X software is used to model four processes. Based on the modeling result of four processes, the amounts of GHG emissions and the sludge produced from each process are calculated by Intergovernmental Panel on Climate Change(IPCC) 2006 guideline report. GHG emissions for water as well as sludge treatment processes are calculated for environmental assessment has been done on the scenario of various sludge treatments, such as composting, incineration and reclamation and each scenario is compared by using a unified index of the economic and environmental assessment. It was found that Bardenpho process among these processes shows a best process that can emit minimum amount of GHG with lowest impact on environment and composting emits the minimum amount of GHG for sludge treatment.

A Documentational Study on the Development of Chi-Kung-Hak (기공학(氣功學) 발달(發達)에 관한 문헌적(文獻的) 연구(硏究))

  • Kim Woo-Ho;Hong Won-Sik
    • Journal of Korean Medical Ki-Gong Academy
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    • v.1 no.1
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    • pp.13-59
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    • 1996
  • Dep. of Classics &Medical History, College of Oriental Medicint, Kyung Hee University Today, many people are more interested Today, many people are more interested in preventing the disease than curing it. Chi-Kung(氣功) is the way of Life-Cultivation(養生法) peculiar to the orient, it is reported in china that Chi-Kung has an excellent curative value not only in curing the disease but also in preventing it. But the full-scale study of Chi-Kung is not be made up to now in Korea, so I studied the developmental history of chinese Chi-Kung through the oriental medical books. From this study, I reached the following conclusions; 1. Chi-Kung is naturally derived from the self-preservation instinct to adapt oneself to circumstances of the nature, but in the investigation from the documentational records, it is originated in the treatment method of the Sam-Huang-O-Jae(三皇五帝) period to cure the abnormal circulation of the vital force and blood caused by damp(濕). 2. As the principle and the method of the Life-Cultivation of the Chun-Chu-Jeon-Kook(春秋戰國) period were recorded in Huang-Jae-Nai-Gyung(黃帝內經) detailly and the remedy examples by ancient Chi-Kung such as Tao-Yin(導引), Haeng-Chi(行氣) were presented, we considered that theoretical basis of the development of Life-cultivation and Chi-Kung study was furnished in that period. 3. A famous doctor, Hwa-Ta(華引) lived in Han dynasty, researched the theory and practice of Tao-Yin transmitted from the former generations, as that result, he formed a kind of medical, gymnastics what is called O-Keum-Hi(五禽?). It is considered that 'O-Keum-Hi' is a Tao-Yin method developed more practically and systemetically than the Tao-Yin appeared in the 'Jang-Ja'(莊子) or 'Hoy-Nam-Ja'(淮南子). 4. In Wui-Jin-Nambook-Jo(魏曺南北朝) periods, the contents of Chi-Kung were more abundant under the influence of Buddhism(佛敎) and Taoism(道敎). Galhong(葛洪), the author of 'Po-Bak-Ja'(抱朴子) arranged the ancient Chi-Kung method systematically first of all, Tao-Goeng-Gyung, the author of 'Yang-Seong-Yeun-Myung-Rok'(養性延命錄) recorded the 'Yook-Ja-Geul'(六字訣) first time. 5. There is a new development of Chi-Kung therapy in Soo-Tang-Odae(隋唐五代) periods, especially So-Won-Bang(巢元方), the author of 'Jey-Bang-Won-Hwu-Ron' collected almost all of the Chi-Kung method, for curing the disease formed before Soo(隋) period. From that fact, we supposed that Chi-Kung was utilized more widely in curing the disease. 6. 'So-Ju-Cheon-Hwa-Hu-Peob'(小周天火候法) was adopted as the best orthodox approach under the influence of Nae-Tan-Taoist(道敎內丹學波) in Song-Keum-Won(宋金元) periods, especially in the song dynasty, 'Pal-Dan-Geum'(八段錦) was appearde and assignment of six-Chi(六氣) for bowel and viscera in the 'Yook-Ja-Geul'(六字訣) was decided firmly, that is to say Lung-Si(肺-?), Heart-Kha(心-呵), Spleen-Hoa(脾-呼), liver-Hoe(肝-噓), Kidney-chui(賢-吹), Three-Burner-shi(三焦-?). 7. In Myung-Cheong(明淸) periods, The general practitioner applied the principle of 'Byun-Jeng-Ron-Chi(辨證論治) to the Chi-Kung field, and after Myung dynasty the style of doing 'Yook-Ja-Gyel'(六字訣) was developed to the moving style. 8. Today, in china, the study on the Chi-Kyung is being progressed constantly under the positive assistance of government, Chi-Kung-Hak(氣功學) has taking its place as a branch of study step by step. It is considered that the establishment of Chi-Kung-Hak Classroom(氣功學敎室) and Medical Chi-Kung Center(氣功療法室) for special and systematic research are needed, at the same time the settlement of institutional system for training the Chi-Kung technician(氣功師) is also needed.

Examining the Formation of Entrepreneurial Activities through Cognitive Approach (기업가적 활동 형성에 미치는 영향요인: 인지론적 접근)

  • Lee, Chaewon
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.12 no.3
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    • pp.65-74
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    • 2017
  • There have been questions how entrepreneurs think, act and why individuals become entrepreneurs. The trait-based explanation of entrepreneurial activities has been main stream. However, the trait-based theory has been criticized because it assumes that entrepreneurial traits are inherited, stable and enduring over time. This research accepts the cognitive theory to see how entrepreneurs learn or accept others' values, how entrepreneurial perceptions of opportunity impact entrepreneurial actions and how individuals acquire the social legitimation of the formation of entrepreneurial activities. In order to capture the attitudes, activities and motivations of people who are involved in entrepreneurial activities, the author uses the GEM Korea 2016 data. The data from the Global Entrepreneurship Monitor(GEM) has been well known for the data to capture individuals early-stage entrepreneurial activities. This paper used the sample from the APS(Adult Population Survey) of the GEM which was completed by a representative sample of two thousand adults in Korea by the qualified survey vendor, with strict procedures and oversight by the GEM central data team. The hypotheses are tested with logit regression analysis to estimate the probability of the influence of perceptual variables such as individual perception in social learning, the opportunity recognition in the environment, and social legitimation in the entrepreneurial activities. Based on the results, individuals tend to have high entrepreneurial activities if individuals have high self-efficacy. Also, the existence of role models around the entrepreneurs encourages the individuals involve in entrepreneurial activities more however the perception of opportunity in the environment is not strongly associated with entrepreneurial activities. The media exposure of successful entrepreneurs is more important than others' perception of entrepreneurs on the desirable career option or respect from communities. This paper can contribute to the cognitive processes, particular perception about oneself, as well as perception which is impacted by a community or a society.

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The Optimal Configuration of Arch Structures Using Force Approximate Method (부재력(部材力) 근사해법(近似解法)을 이용(利用)한 아치구조물(構造物)의 형상최적화(形狀最適化)에 관한 연구(研究))

  • Lee, Gyu Won;Ro, Min Lae
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.13 no.2
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    • pp.95-109
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    • 1993
  • In this study, the optimal configuration of arch structure has been tested by a decomposition technique. The object of this study is to provide the method of optimizing the shapes of both two hinged and fixed arches. The problem of optimal configuration of arch structures includes the interaction formulas, the working stress, and the buckling stress constraints on the assumption that arch ribs can be approximated by a finite number of straight members. On the first level, buckling loads are calculated from the relation of the stiffness matrix and the geometric stiffness matrix by using Rayleigh-Ritz method, and the number of the structural analyses can be decreased by approximating member forces through sensitivity analysis using the design space approach. The objective function is formulated as the total weight of the structures, and the constraints are derived by including the working stress, the buckling stress, and the side limit. On the second level, the nodal point coordinates of the arch structures are used as design variables and the objective function has been taken as the weight function. By treating the nodal point coordinates as design variable, the problem of optimization can be reduced to unconstrained optimal design problem which is easy to solve. Numerical comparisons with results which are obtained from numerical tests for several arch structures with various shapes and constraints show that convergence rate is very fast regardless of constraint types and configuration of arch structures. And the optimal configuration or the arch structures obtained in this study is almost the identical one from other results. The total weight could be decreased by 17.7%-91.7% when an optimal configuration is accomplished.

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