• Title/Summary/Keyword: Yonsei University

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Corporate Credit Rating based on Bankruptcy Probability Using AdaBoost Algorithm-based Support Vector Machine (AdaBoost 알고리즘기반 SVM을 이용한 부실 확률분포 기반의 기업신용평가)

  • Shin, Taek-Soo;Hong, Tae-Ho
    • Journal of Intelligence and Information Systems
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    • v.17 no.3
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    • pp.25-41
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    • 2011
  • Recently, support vector machines (SVMs) are being recognized as competitive tools as compared with other data mining techniques for solving pattern recognition or classification decision problems. Furthermore, many researches, in particular, have proved them more powerful than traditional artificial neural networks (ANNs) (Amendolia et al., 2003; Huang et al., 2004, Huang et al., 2005; Tay and Cao, 2001; Min and Lee, 2005; Shin et al., 2005; Kim, 2003).The classification decision, such as a binary or multi-class decision problem, used by any classifier, i.e. data mining techniques is so cost-sensitive particularly in financial classification problems such as the credit ratings that if the credit ratings are misclassified, a terrible economic loss for investors or financial decision makers may happen. Therefore, it is necessary to convert the outputs of the classifier into wellcalibrated posterior probabilities-based multiclass credit ratings according to the bankruptcy probabilities. However, SVMs basically do not provide such probabilities. So it required to use any method to create the probabilities (Platt, 1999; Drish, 2001). This paper applied AdaBoost algorithm-based support vector machines (SVMs) into a bankruptcy prediction as a binary classification problem for the IT companies in Korea and then performed the multi-class credit ratings of the companies by making a normal distribution shape of posterior bankruptcy probabilities from the loss functions extracted from the SVMs. Our proposed approach also showed that their methods can minimize the misclassification problems by adjusting the credit grade interval ranges on condition that each credit grade for credit loan borrowers has its own credit risk, i.e. bankruptcy probability.

Effect of Automatic Exposure Control Marker with Chest Radiography in Radiation Reduction (자동노출제어를 사용한 X선 흉부촬영에서 AEC 표지자 사용에 따른 환자 피폭선량 감소 효과)

  • Jung, Ji-Sang;Choi, Byoung-Wook;Kim, Sung-Ho;Kim, Young-Mo;Shim, Ji-Na;Ahn, Ho-Sik;Jin, Duk-Eun;Lim, Jae-Sik;Kang, Sung-Ho
    • Journal of radiological science and technology
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    • v.37 no.3
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    • pp.177-185
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    • 2014
  • This study focused on effects of patient exposure dose reduction with AEC (Auto Exposure Control) marker that is designed for showing location of AEC in X-ray Chest radiography. It included 880 adults who have to use Chest X-ray Digital Radiography system (DRS, LISTEM, Korea). AEC (Ion chambers are posited in top of both sides) are used to every adult and set X-ray system as Field size $17{\times}17inch$, 120kVp, FFD 180cm. 440 people of control group are posited on detector to include both sides of lung field and the other 440 people of experimental group are set to contact their lung directly to Ion chamber (making marker to shows location). Then, measured every DAP and, estimated patient effective dose by using PCXMC 2.0. The average age of control group (M:F=245:195) is 53.9 and the average BMI is 23.4. BMI ranges from under weight: 35, normal range: 279, over weight: 106 to obese: 20 and average DAP is 223.56mGycm2, Mean effective dose is 0.045mSv. The average age of experimental group (M:F=197:243) is 53.7 and the average BMI is 22.7. BMI ranges from under weight: 34, normal range: 315, over weight: 85 to obese: 6 and average DAP is 207.36mGycm2, Mean effective dose is 0.041mSv. Experimental group shows less Mean effective dose as 0.004mSv (9.7%) than control group. Also, patient numbers who got over exposure more than 0.056mSv (limit point to know efficiency of AEC marker) is 65 in control group (14.7%), 19 in experimental group (4.3%) and take statistics with t-Test. The statistical difference between two groups is 0.006. In order to use proper amount of X-ray in auto exposure controlled chest X-ray system, matching location between ion chamber and body part is needed, and using AEC marker (designed for showing location of ion chamber) is a way to reduce unnecessary patient exposure dose.

Isolation and Mycelial Cultivation Submerged of Phellinus sp. (Phellinus sp.의 분리 및 균사체의 액체배양)

  • Kang, Tae-Su;Lee, Dong-Gi;Lee, Shin-Young
    • The Korean Journal of Mycology
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    • v.25 no.4 s.83
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    • pp.257-267
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    • 1997
  • Fruit bodies similar to the Phellinus sp. residing on the mulberry were collected at Yang-yang in Kang-won-do province and one strain of Phellinus sp. was isolated from the fruit bodies. For mass production of the isolated mycelia in a submerged culture, the culture conditions, medium composition, and the effect of various culture systems on the mycelial growth, were investigated. The morphological characteristics of the fruit body were as follows: covered with blackish to black and rough, lower surface with yellowish-brown to dull-brown and smooth, 5-7 cm thick and hard woody. Also, the pure cultured mycelia showed yellowish-brown color, capability of purplish-brown pigment production on the PDA plate media, no-formation of clamp-connection, much binding branch, and enzyme activities such as laccase, tyrosinase and peroxidase. Therefore, pure cultured strain was identified to be Phellinus sp. In the flask culture, the optimum culture conditions for the mycelial production were obtained after cultivation of 8 days at inoculum level of 5%(v/v), media volume of 70 mL, 150 rpm, initial pH 6, and temperature of $30^{\circ}C$. Optimum medium composition from the response surface analysis were determined to be glucose 12.12 g/L, sucrose 12.12 g/L, yeast extract 11.15 g/L, malt extract 11.15 g/L, $KH_2PO_4$ 0.855 g/L and $CaCl_2$ 0.855 g/L. The production of the mycelia after 4 and 8 days of cultivation was 1.95 and 9.89 g/L, respectively. The maximum specific growth rate and productivity were $0.020\;hr^{-1}$ and 1.25 g/L/day, respectively. Among the three different culture systems for the growth of mycelia, the maximum mycelial dry weight of 7.5 g/L was obtained after cultivation of 4 days in the air-lift fermentor under aeration rate of 2.5 vvm. The maximum specific growth rate and productivity were $0.033\;hr^{-1}$ and 1.9 g/L/day, respectively, which were about 1.7 and 4.2 times higher than those of flask culture.

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Collaboration Strategies of Fashion Companies and Customer Attitudes (시장공사적협동책략화소비자태도(时装公司的协同策略和消费者态度))

  • Chun, Eun-Ha;Niehm, Linda S.
    • Journal of Global Scholars of Marketing Science
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    • v.20 no.1
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    • pp.4-14
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    • 2010
  • Collaboration strategies entail information sharing and other varied forms of cooperation that are mutually beneficial to the company and stakeholder groups. This study addresses the specific types of collaboration used in the fashion industry while also examining strategies that have been most successful for fashion companies and perceived benefits of collaboration from the customer perspective. In the present study we define fashion companies and brands as collaborators and their partners or stakeholders as collaboratees. We define collaboration as a cooperative relationship where more than two companies, brands or individuals provide customers with beneficial outcomes utilizing their own competitive advantages on an equal basis. Collaboration strategies entail information sharing and other varied forms of cooperation that are mutually beneficial to the company and stakeholder groups. Through collaboration, fashion companies have pursued both tangible differentiation, such as design and technology applications, and intangible differentiation such as emotional and psychological benefits to customers. As a result, collaboration within the fashion industry has become an important, value creating concept. This qualitative study utilized case studies and in-depth interview methodologies to examine customers' attitudes concerning collaboration in the fashion industry. A total of 173 collaboration cases were identified in Korean and international markets from 1998 through December 2008, focusing on fashion companies. Cases were collected from documented data including websites and industry data bases and top ranked portal search sites such as: Rankey.com; Naver, Daum, and Nate; and representative fashion information websites, Samsungdesignnet and Firstviewkorea. Cases were collected between November 2008 and February 2009. Cases were selected for the analysis where one or more partners were associated with the production of fashion products (excluding textile production), retail fashion products, or designer services. Additional collaboration case information was obtained from news articles, periodicals, internet portal sites and fashion information sites as conducted in prior studies (Jeong and Kim 2008; Park and Park 2004; Yoon 2005). In total, 173 cases were selected for analysis that clearly exhibited the benefits and outcomes of collaboration efforts and strategies between fashion companies and stakeholders. Findings show that the overall results show that for both partners (collaborator and collaboratee) participating in collaboration, that the major benefits are reduction of costs and risks by sharing resource such as design power, image, costs, technology and targets, and creation of synergy. Regarding types of collaboration outcomes, product/design was most important (55%), followed by promotion (21%), price (20%), and place (4%). This result shows that collaboration plays an important role in giving life to products and designs, particularly in the fashion industry which seeks for creative and newness. To be successful in collaboration efforts, results of the depth interviews in this study confirm that fashion companies should have a clear objective on why they are doing the collaboration. After setting the objective, they should select collaboratees that match their brand image and target market, make quality co-products that have definite concepts and differentiating factors, and also pay attention to increasing brand awareness. Based on depth interviews with customers, customer benefits were categorized into six factors: pursuit for individual character; pursuit for brand; pursuit for scarcity; pursuit for fashion; pursuit for economic efficiency; and pursuit for sociality. Customers also placed more importance on image, reputation, and trust of brands regarding the cases shown in the interviews. They also commented that strong branding should come first before other marketing strategies. However, success factors recognized by experts and customers in this study showed different results by subcategories. Thus, target customers and target market should be studied from various dimensions to develop appropriate strategies for successful collaboration.

Ultrastructure of Germ Cells, Cyst Epithelial Cells and Interstitial Cells during Spermatogenesis of the Stone Flounder, Kareius bicoloratus (돌가자미 Kareius bicoloratus의 정자형성과정 중 생식세포, Cyst 상피세포 및 간질세포의 미세구조)

  • Jun, Je-Cheon;Chung, Ee-Yung;Yang, Young Chul
    • Korean Journal of Ichthyology
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    • v.18 no.4
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    • pp.311-318
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    • 2006
  • Ultrastructure of germ cells, the cyst epithelial cells and interstitial cells during spermatogenesis of the stone flounder, Kareius bicoloratus (Pleuronectidae) sampled on the west coast of Korea were investigated by electron microscopic observations. In the primary spermatocyte, the synaptonemal complexes appear in the zygotene stage of the prophase during maturation division. In the growing testis, especially, the interstitial cells (Leydig cells) appear near the primary, secondary spermatocytes and spermatids. Well-developed interstitial cells (steroid hormone secreting cells) which are located in the interlobular space in growing testis have three morphological characteristics of a vesicular nucleus, mitochondria with tubular cristae and smooth endoplasmic reticulum. During spermatogenesis, the primary and secondary spermatocytes attach to the cyst epithelial cell (Sertoli cell) having an elongated ovoid or triangular nucleus and several mitochondria in the cytoplasm. In the growing testis, lipid droplets, the mitochondrial rosettes and glycogen particles appear in the cytoplasm of the cyst epithelial cells near the secondary spermatocytes and spermatids. Particularly, the mitochondria, endoplasmic reticulum, little lipid droplets and the large amount of glycogen particles are present in the cytoplasm of the cyst epithelial cell in the late growing testis. In the late stage of spermiogenesis, the proximal centriole is joined to the nuclear envelope, the distal centriole forms the basal body of the flagellum and gives rise to the axial filament of the flagellum. No acrosome of the sperm is formed as seen in other teleost fish. The head of the spermatozoon is approximately $3{\mu}m$ in length and its tail is about $30{\mu}m$ in length. The axoneme of the tail flagellum of the spermatozoon consists of nine outer doublet microtubules at the periphery and two centrial singlet microtubules at the center. The spermatozoon of this species has two axonemal lateral fins. Especially, the cyst epithelial cells which located near groups of gametes in the various stages, show three functions: nutrition, phagocytosis and steroidogenesis. Especially, the nuclei of cyst epithelial cells in the recovery stage of the testicular developmental stages appear to be irregular in shape after spermiation. Of three functions of the cyst epithelial cell, several characteristics of phagocytosis are showed in the cytoplasm of the cyst epithelial cells in the recovery stage of the testicular developmental stages. At this stage, therefore, it is assumed that the cyst epithelial cells are involved in degeneration and resorption of undischarged germ cells after spermiation.

A Verification on the Effectiveness of Middle Managers' Emotional Leadership in Food Service Management Companies (위탁급식업체 중간관리자의 감성리더십 효과성 검증)

  • Kim, Hyun-Ah;Jung, Hyun-Young
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.36 no.4
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    • pp.488-498
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    • 2007
  • The purposes of this study were to: a) provide evidences concerning the effects of emotional leadership b) examine the impacts of emotional leadership on employee-related variables, 'job satisfaction', 'organizational commitment', 'organizational performance' and 'turnover intention', and c) identify a conceptual framework underlying emotional leadership. A survey was conducted from August 23 to November 3, 2005 to collect data from mid-level managers in food service company headquarters (N=219). Statistical analyses were completed using SPSS Win (12.0) for descriptive, reliability, factor and correlation analyses and AMOS (5.0) for confirmatory factor analysis and structural equation modeling. The main results of this study were as follows. First, the managers gave the highest point to their leaders in the emotional leadership competence 'organizational awareness : reading the currents, decision networks, and politics at the organizational level' and gave the lowest point in the emotional leadership competence 'influence: wielding effective tactics for persuasion'. Second, the means of job satisfaction was above the midpoint (3 points). Employees' job satisfaction with 'coworkers' was relatively high. However, the extents of satisfaction with 'payroll' 'promotion', and 'work environment' were relatively low. Third, the organizational commitment was above the midpoint (3 points). In the organizational commitment, 'loyalty' factor was higher than 'commitment' factor. Fourth, the means of organizational performance was above the midpoint. The highest organizational performance variable was 'internal efficiency; trying to reduce cost' and the lowest organizational performance variable was 'internal fairness ; equitable treatment and all are treated with respect with no regard to status and grade'. Fifth, most respondents intended on 'thinking of quitting ; towards turnover process'. Sixth, the test of hypothesis using structural equation modeling found that emotional leadership produced p[Isitive effects on job attitude and job performance. Emotional leadership enhanced job satisfaction and organizational commitment, and in turn, employees' attitude positive effects on organizational performance; emotional leadership also had a direct impact on organizational performance

A study on the xylographica of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ ("의방류취(醫方類聚)"에 대한 판본(版本) 연구)

  • Shin, Soon-Shik;Choi, Hwan-Soo
    • Korean Journal of Oriental Medicine
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    • v.3 no.1
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    • pp.1-15
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    • 1997
  • ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$(1445) is a book compiled the medical achievements of China and Choseon in those times and it's our source of pride to have it In this country. It also deserves careful investigation since this book can provide some clues of features of missing books in China and Korea. The extent of accuracy of xylographica of old books determines the possiblity of in depth further study. So authors attempted to investigate the xylographica of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ one of the 3 main books in Korea. Previous investigation done by Miki Sakae and Kim Doo Jong are noticeable. On the basis of their respective works, we analyzed 'Annals of the Choseon Dynasty' to find records related with ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ and estimated the situation of its publication. We tried figure the situation of those times of China, Japan and Korea(including North Korea) and tried to estimate the book's original xylographica as much as we could. By King Sejong's command, the first draft of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ consisted of 365 books was made by collaboration of civil officials and medical officers during the period from 1443 to 1445. And then from 1451(first year of Moonjong's reign) to 1464(l0th year of Sejo's reign) lots of manpowers were employed and through the process of countless erasure, proofreading, arrangement and rearrangement revised version of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ which is called by Sejo text was completed. After 3 years of wood engraving work, the first printed form of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ (alternately called Seongjong text) in folding case consisted of 266 chapters, 264 volumes came into the world in 1477.(8th year of Seongjong's reign). This was 32 years after the initial completion of the edition. So ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ exists in three forms as Sejong text, Sejo text and Seongjong text respectively. Since those texts were plundered during the Japanese invasion of Korea in 1592, none of the original copy remains within korea. The texts were constantly moved to kadeungcheongieong, to Kongdeungpyeongio, Jesookoan of Edo, to East University of department of classic books, to Cheoncho archives, to the Imperial Museum and finally is kept in the royal palace at present. (Doseoryo text Eulhae printing type) Reduced-size republication books of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ in wooden type were imported at the time of 'Byeongja Korea-Japan Treaty in 1876' and of those 2 books, one copy was treasured in the Royal Household of the Yi Dynasty and than was lost during the Korean War circa 1950. The other remaining copy has been kept succesively by Kojong's imperial grant, Royal doctor Hong Cheol Bo, Hong Taek Joo, Hong Ik Pyo the book agent, and now is kept In Yonsei University Library and this is the only existing copy in Korea at present. In 1965, Dongyang Medical college published the transcription version of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ consisting of 11 books and then in 1981 after edition and arrangement by Choonghoa(中華) publishing company, photoprint copy of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ was published in Keumgang(金剛) publishing company In 1991, October Yeokang(驛江) publishing company producd photocopies of ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ which were previously translated into Korean by North Korea Institute of Oriental Medicine and then issued by medical publishing company. In China, two institutes, Zhejiang Institute of Traditional Chinese Medicine and Huzhou Traditional Chinese Medical Hospital cooperated to publish a revised and marked text consiting of 11 books by adding marking points to japanse Edohakhoondang text which were used as a reference. Both the korean and chinese texts issued were grounded by the ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ kept in the royal palace. Any further study concerning ${\ulcorner}$Classified Collection of Medical Prescriptions${\lrcorner}$ can acquire its accuracy and objectivity when the japanese text kept in the royal palace is taken as an original copy.

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Clinical Characteristics of Tuberculosis in North Korean Refugees (북한이탈주민에서의 결핵의 임상적 고찰)

  • Choi, Chang-Min;Jeong, Woo-Kyoung;Kang, Cheol-In;Kim, Doh-Hyung;Kim, Young-Keun;Heo, Sang-Taek;Kim, Hee-Jin
    • Tuberculosis and Respiratory Diseases
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    • v.60 no.3
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    • pp.285-289
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    • 2006
  • Background : North Korea's economic and public health problems began in the early 1990s as a result of the gradual loss of economic support from its communist allies, combined with an inordinate number of natural disasters. The decline in public health has increased the incidence of tuberculosis in North Koreans and refugees. This study investigated tuberculosis situation in North Korean refugees in order to prepare for the future impact of tuberculosis control in Korea. Material and Methods : From 2001 to 2005, tuberculosis patients among North Korean refugees who were diagnosed before or after arriving in South Korea, based on the official records of OO hospital, were enrolled in this study. The demographic and clinical data of the cases were evaluated retrospectively. Results : A total of 42 TB cases were reviewed during the study period. Of these, 37 (88.1%) cases were pulmonary TB. based on the cases identified among the number of North Korean refugees' arriving each year, the annual incidence of pulmonary TB were 900 per 100,000 in 2004, 700 in 2003, The number of smear-positive patients was 20 (47.6%) and the number of culture-positive patients was 18 (42.9%). Of the M. tuberculosis isolates, 2 cases were found to be susceptible to all anti-TB drugs available, 4 were resistant to isoniazid, and 3 were multi-drug resistant. Conclusion : The prevalence of pulmonary TB in North Korean Refugees is high. In addition, North Korean refugees suffer from more severe tuberculosis in bacteriological and radiological aspects.

A Comparative Case Study on the Adaptation Process of Advanced Information Technology: A Grounded Theory Approach for the Appropriation Process (신기술 사용 과정에 관한 비교 사례 연구: 기술 전유 과정의 근거이론적 접근)

  • Choi, Hee-Jae;Lee, Zoon-Ky
    • Asia pacific journal of information systems
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    • v.19 no.3
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    • pp.99-124
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    • 2009
  • Many firms in Korea have adopted and used advanced information technology in an effort to boost efficiency. The process of adapting to the new technology, at the same time, can vary from one firm to another. As such, this research focuses on several relevant factors, especially the roles of social interaction as a key variable that influences the technology adaptation process and the outcomes. Thus far, how a firm goes through the adaptation process to the new technology has not been yet fully explored. Previous studies on changes undergone by a firm or an organization due to information technology have been pursued from various theoretical points of views, evolved from technological and institutional views to an integrated social technology views. The technology adaptation process has been understood to be something that evolves over time and has been regarded as cycles between misalignments and alignments, gradually approaching the stable aligned state. The adaptation process of the new technology was defined as "appropriation" process according to Poole and DeSanctis (1994). They suggested that this process is not automatically determined by the technology design itself. Rather, people actively select how technology structures should be used; accordingly, adoption practices vary. But concepts of the appropriation process in these studies are not accurate while suggested propositions are not clear enough to apply in practice. Furthermore, these studies do not substantially suggest which factors are changed during the appropriation process and what should be done to bring about effective outcomes. Therefore, research objectives of this study lie in finding causes for the difference in ways in which advanced information technology has been used and adopted among organizations. The study also aims to explore how a firm's interaction with social as well as technological factors affects differently in resulting organizational changes. Detail objectives of this study are as follows. First, this paper primarily focuses on the appropriation process of advanced information technology in the long run, and we look into reasons for the diverse types of the usage. Second, this study is to categorize each phases in the appropriation process and make clear what changes occur and how they are evolved during each phase. Third, this study is to suggest the guidelines to determine which strategies are needed in an individual, group and organizational level. For this, a substantially grounded theory that can be applied to organizational practice has been developed from a longitudinal comparative case study. For these objectives, the technology appropriation process was explored based on Structuration Theory by Giddens (1984), Orlikoski and Robey (1991) and Adaptive Structuration Theory by Poole and DeSanctis (1994), which are examples of social technology views on organizational change by technology. Data have been obtained from interviews, observations of medical treatment task, and questionnaires administered to group members who use the technology. Data coding was executed in three steps following the grounded theory approach. First of all, concepts and categories were developed from interviews and observation data in open coding. Next, in axial coding, we related categories to subcategorize along the lines of their properties and dimensions through the paradigm model. Finally, the grounded theory about the appropriation process was developed through the conditional/consequential matrix in selective coding. In this study eight hypotheses about the adaptation process have been clearly articulated. Also, we found that the appropriation process involves through three phases, namely, "direct appropriation," "cooperate with related structures," and "interpret and make judgments." The higher phases of appropriation move, the more users represent various types of instrumental use and attitude. Moreover, the previous structures like "knowledge and experience," "belief that other members know and accept the use of technology," "horizontal communication," and "embodiment of opinion collection process" are evolved to higher degrees in their dimensions of property. Furthermore, users continuously create new spirits and structures, while removing some of the previous ones at the same time. Thus, from longitudinal view, faithful and unfaithful appropriation methods appear recursively, but gradually faithful appropriation takes over the other. In other words, the concept of spirits and structures has been changed in the adaptation process over time for the purpose of alignment between the task and other structures. These findings call for a revised or extended model of structural adaptation in IS (Information Systems) literature now that the vague adaptation process in previous studies has been clarified through the in-depth qualitative study, identifying each phrase with accuracy. In addition, based on these results some guidelines can be set up to help determine which strategies are needed in an individual, group, and organizational level for the purpose of effective technology appropriation. In practice, managers can focus on the changes of spirits and elevation of the structural dimension to achieve effective technology use.

Separate and Combined Effect of Cadmium and Nickel on Blood Pressure in Rats (흰쥐에서 카드뮴과 니켈이 혈압에 미치는 효과)

  • Cha, Bong-Suk;Wang, Seung-Jun
    • Journal of Preventive Medicine and Public Health
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    • v.34 no.2
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    • pp.127-130
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    • 2001
  • Objective : To verify the separate and combined effects of cadmium and nickel on blood pressure in rats. Methods : Following the daily administration of cadmium chloride$(CdCl_2)$ and nickel chloride$(NiCl_2)$ to rats both individually and in combination with intraperitoneal injection method for one week, systolic blood pressure of the tail was measured at 1 day and 5, 10, 20, 30 days after administration. Each substance was injected into the rats with 0.1 mg/kg bw and 1.0 mg/kg bw concentration. Results : After 0.1 mg/kg bw $CdCl_2$ was injected, a statistically significant difference was found as compared with the control group(only saline) after 1, 5 and 10 days. After 0.1 mg/kg bw $NiCl_2$ was injected, a statistically significant difference was not found compared with the control group. After 0.1 mg/kg bw $CdCl_2$ and 0.1 mg/kg bw $NiCl_2$ were injected simultaneously, a statistically significant difference was found as compared with the control group after 1,5 and 10 days and compared with 0.1 mg/kg bw $CdCl_2$ group after 5 days and as compared with 0.1 mg/kg bw $NiCl_2$ group after 5 and 10 days. After 1.0 mg/kg bw $CdCl_2$ was injected, a statistically significant difference was found as compared with the control group after 1, 5, 10 and 20 days. After 1.0 mg/kg bw $NiCl_2$ was injected, a statistically significant difference was found as compared with the control group after 1 day and 5 days. After 1.0 mg/kg bw $CdCl_2$ and 1.0 mg/kg bw $NiCl_2$ were injected in combination, a statistically significant difference was found after 1, 5, 10, 20 and 30 days as compared with 1.0 mg/kg bw $CdCl_2$ after 10, 20 and 30 days and as compared with 1.0 mg/kg bw $NiCl_2$ after 5, 10, 20 and 30 days. Conclusion : It was found that the effect of $CdCl_2$ on blood pressure was much more than $NiCl_2$ and a high concentration $CdCl_2\;and\;NiCl_2$ in combination delayed the recovery of blood pressure.

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