• Title/Summary/Keyword: 기술적

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EFFECT OF ULTRASONIC VIBRATION ON ENAMEL AND DENTIN BOND STRENGTH AND RESIN INFILTRATION IN ALL-IN-ONE ADHESIVE SYSTEMS (All-in-one 접착제에서 초음파진동이 법랑질과 상아질의 결합강도와 레진침투에 미치는 영향)

  • Lee, Bum-Eui;Jang, Ki-Taeg;Lee, Sang-Hoon;Kim, Chong-Chul;Hahn, Se-Hyun
    • Journal of the korean academy of Pediatric Dentistry
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    • v.31 no.1
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    • pp.66-78
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    • 2004
  • The objective of this study was to apply the vibration technique to reduce the viscosity of bonding adhesives and thereby compare the bond strength and resin penetration in enamel and dentin achieved with those gained using the conventional technique and vibration technique. For enamel specimens, thirty teeth were sectioned mesio-distally. Sectioned two parts were assigned to same adhesive system but different treatment(vibration vs. non-vibration). Each specimen was embedded in 1-inch inner diameter PVC pipe with a acrylic resin. The buccal and lingual surfaces were placed so that the tooth and the embedding medium were at the same level. The samples were subsequently polished silicon carbide abrasive papers. Each adhesive system was applied according to its manufacture's instruction. Vibration groups were additionally vibrated for 15 seconds before curing. For dentin specimen, except removing the coronal part and placing occlusal surface at the mold level, the remaining procedures were same as enamel specimen. Resin composite(Z250. 3M. U.S.A.) was condensed on to the prepared surface in two increments using a mold kit(Ultradent Inc., U.S.A.). Each increments was light cured for 40 seconds. After 24 hours in tap water at room temperature, the specimens were thermocycled for 1000cycles. Shear bond strengths were measured with a universal testing machine(Instron 4465, England). To investigate infiltration patterns of adhesive materials, the surface of specimens was examined with scanning electron microscope. The results were as follows: 1. In enamel the mean values of shear bond strengths in vibration groups(group 2, 4, 6) were greater than those of non-vibration group(group 1, 3, 5). The differences were statistically significant except AQ bond group. 2. In dentin, the mean values of shear bond strengths in vibration groups(group 2, 4, 6) were greater than those of non-vibration groups(group 1, 3, 5). But the differences were not statistically significant except One-Up Bond F group. 3. The vibration group showed more mineral loss in enamel and longer resin tag and greater number of lateral branches in dentin under SEM examination.

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The Development and Application of Standard Diagnostic Table for Mountain Ginseng Management (산양삼 경영 표준진단표의 개발 및 현지 적용)

  • Jeon, Jun-Heon;Lee, Seong-Youn;Lee, Jung-Min;Ji, Dong-Hyun;Kim, Yeon-Tae;Kang, Kil-Nam
    • Journal of Korean Society of Forest Science
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    • v.103 no.4
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    • pp.622-629
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    • 2014
  • This study aims to develop a standard diagnostic table for mountain ginseng so that the cultivators not only can check their current level of management with the table, but also can understand and address operational challenges better by themselves utilizing the table. The standard diagnostic table consists of 3 categories and 18 subcategories to diagnose the general status of forestry households, the indicators of management performance and the level of management. To develop the table, the study conducted a survey on the actual condition of management, targeting 81 forestry households throughout 15 municipalities including Mu-ju, Jeollabukdo, and Ham-yang, Gyeongsangnamdo, all of which are the chief producing districts of mountain ginseng. Then, the study calculated total scores by regions by aggregating the scores of 18 subcategories, in order to evaluate and compare the management level among regions based on the scores. According to the result, the average score of 81 forestry households was 57.2 point-58% of which surveyed belonged to the range of 40-60 point. Compared by regions, the average score of Jeollabukdo regions was 52.9 point, the lowest, and that of Gyeongsangnamdo regions was 61.4 point, the highest. It is remarkable that among the indicators of management base, the average score of 'mounding (the height of mound)' item was recorded rather low with 1.59 point, reflecting the fact that the cultivators tend to raise mountain ginseng with no additional mounds. As for the indicators of production skills, the average score of the pest control item was remarkably low with 1.28 point. Over 90% of cultivators answered that they do not usually forecast or survey the pest disease in advance. Meanwhile, it is also noticeable that the item of sowing and planting methods, and the item of seed were both rather high, recording 4.00 and 4.47 point respectively. As for the item of management and sales skill, however, the score was rather low with 2.20 point, meaning that the forestry households still have a low interest in the business management.

Learning Curve of a Laparoscopy Assisted Distal Gastrectomy for a Surgeon Expert in Performing a Conventional Open Gastrectomy (개복 위절제술에 경험이 풍부한 술자에 의한 복강경 보조하 원위부 위절제술의 Learning Curve)

  • Kim, Ji-Hoon;Jung, Young-Soo;Jung, Oh;Lim, Jeong-Taek;Yook, Jeong-Hwan;Oh, Sung-Tae;Park, Kun-Choon;Kim, Byung-Sik
    • Journal of Gastric Cancer
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    • v.6 no.3
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    • pp.167-172
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    • 2006
  • Purpose: The laparoscopy assisted gastrectomy has been increasingly reported as the treatment of choice for early gastric cancer. However, expert surgeons, who have performed a conventional open gastrectomy for a long time, tend to have a negative attitude toward laparoscopic procedures. The aim of this study was to determine the learning curve of a laparoscopy assisted distal gastrectomy (LADG) for a surgeon expert in performing an open gastrectomy and to analyze the factors that have an effect on a LADG. Materials and Methods: Between April 2005 and March 2006, 62 patients underwent a LADG with D1+beta lymph-node dissection. The 62 patients were divided into 10 sequential groups with 6 cases in each group (the last group was 8 cases), and the time required to reach the plateau of the learning curve was determined by examining the average operative times of these 10 groups. Other factors, such as sex, BMI, complications, transfusion requirements, the number of retrieved lymph nodes, and change of postoperative hemoglobin level, were also analyzed. Results: With the $5^{th}$ group (after 30 cases), the operative time reached a plateau (average: 170 min/operation). The differences between before the $30^{th}$ case and after the $31^{st}$ case with respect to changes in the postoperative hemoglobin level, the number of retrieved lymph nodes, the transfusion requirements, and the complications rate were not significant. Conclusion: According to an analysis of the operative time, experience with 30 LADGs in patients with early gastric cancer is the point at which the plateau of the learning curve (7 months) is reached. Abundant experience with a conventional open gastrectomy and a well-organized laparoscopic surgery team are important factors in overcoming the learning curie earlier.

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Counseling Case Study of a Child with Peer Confliction due to Lack of Social Skills and Impulsiveness (사회적 기술 부족과 충동성으로 인해 또래갈등이 심한 분교아동의 상담사례)

  • Lee, In-Sun
    • The Korean Journal of Elementary Counseling
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    • v.5 no.1
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    • pp.227-253
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    • 2006
  • It seems common for students living at a small county and islands to experience psychological conflicts and be unaccustomed in the peer society because they are not familiar with peer interaction and social skills. This is a case study of L (hereinafter called L) who was grown up in the sheltered school at a small county. L was psychologically disturbed because he couldn't get along well in the transferred school. It is the reason why he had lived in the sheltered school at a small county, so he had not enough exposure to interact with peer and social skills. Sometimes he was obstinate irrationally and when he had trouble with friends, he threw something out or went out of school and tricked juniors dangerously. The fact of disperse with families, parent's indifference, and hate of older brother made L to have ill feeling against family. He had low motivation and low self confident in learning because of short attention time and accumulated poor learning progress. In this study, he was evaluated at various area, such as, intelligent, affective, personal and inter-personal, before counselling. To evaluated the effect of the counselling, K-WISC-III, KPRC, sentence filling test, social adaptation ability test, etc, were administered right after the counselling was over and 8 weeks later. For specific information gathering and analysing, observation diary and deepen counselling were accomplished by homeroom teacher, his mother, and his peers. To correct his problematic behaviors, 13 counseling sessions were accomplished for 6 months and those counselling sessions were recorded and analysed definitely. Followings are the result of this case study. First, he was recovered from the anxiety of inter-personal interaction and he started to interact with peers. The result of sac scale score of KPRC profile was lower than before as much as average student after counseling and 8 weeks later. This reveals that the distress against interpersonal relation have settled. Especially, through the result of sentence filing test, he seemed to feel attachment to peers and be positive, active in the relation of peer. For instance, he was active in the open class lesson and interacted well with peers. It could be said that he overcame the psychological distress comparing with previous time. Second, he could apologize to his peer and juniors for his fault. His attitude were well shown in the letter from an old friend at the sheltered school, average KPRC profiling score comparing with previous counseling time, and remarkable decrease of attack scale score of teacher and peer. Third, his view toward family turn out positive. He recognized his situation that he lived apart from family and even worried about his parent's financial difficulty. Through solving the confliction with his older brother, he could acquire the feeling of family reunion. Fourth, his learning motivation and self-confidence were increased. He confirmed his future positively and he might be judged more attentive because his intelligence index was higher than before as much as average student. With the main goal of this study, verification for effectiveness of counseling. understanding and helping problematic students such as L who lives at a small county and island through investigation of their real situation and problems with the method of counseling and socio-cultural analysis is worthwhile. Identification of ideal relationship with peer is related with positive self-conception, harmonic social adaptation and development of child. It is time to investigate easy adaptive in classroom and well-organised program to acquire general social skills for sheltered school students at a small county and islands.

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Spawning Behavior, Egg and Larvae Developments of Maroon Clownfish, Premnas biaculeatus (Maroon Clownfish, Premnas biaculeatus의 산란습성과 난 발생 및 자치어의 외부형태발달)

  • Kim, Jong-Su;Choi, Young-Ung;Rho, Sum;Yoon, Young-Seock;Jung, Min-Min;Song, Young-Bo;Lee, Chi-Hoon;Lee, Young-Don
    • Journal of Aquaculture
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    • v.20 no.2
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    • pp.96-105
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    • 2007
  • A pair of maroon clownfishes with an indonesian native, reared in recirculation culture system to develope its aquaculture techniques. Courtship, spawning behavior, egg developments and rearing of the maroon clownfish larvae were documented. The larval development were described with illustrative figures. The spawning was occurred 8 times between Feburary and August 2004. The gravid female spawned during 15:00-20:00. The male mainly took care of the eggs supplying oxygen by water currents using their pectoral fins, anal fin and mouth. The fertilized eggs were separative-adhesive and oval in shape, and $1.99{\pm}0.03\;mm$ in longer diameter and $0.88{\pm}0.03\;mm$ in shorter diameter. The fertilized eggs were in deep-orange color. Cleavage occurred in 30 minutes after fertilization, and the egg reached 2 cells stage in 1 hour 10 minutes after fertilization at $27.0^{\circ}{\pm}0.5^{\circ}C$. The embryo was formed in 23 hours 40 minutes after fertilization. Hatching began in between $120{\pm}2$ hours and $150{\pm}12$ hours after fertilization at $27.0^{\circ}C$ in the incubator. Total length (TL) of the newly hatched larvae was 3.22 mm with mouth and anus opened. Ten days after hatching, mean TL of the larvae were 6.21 mm with 28 dorsal fin rays, 17 anal fin rays and 28 caudal fin rays. Nineteen days after hatching, mean TL of the larvae were 9.34 mm. At this stage the larva had three white bands on the body, and they began to feed on commercial diet.

Symptoms of Temporomandibular Disorders in the Korean Adults: An Epidemiological Study (19-65세 한국 성인의 악관절질환의 증상에 관한 실태조사)

  • Kim, Ah-Hyeon;An, So-Yeon;Kim, Min-Jeong;Lee, Eon-Hwa
    • Journal of Dental Rehabilitation and Applied Science
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    • v.27 no.3
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    • pp.277-284
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    • 2011
  • This study is based on the data of adults between ages of 19~65 yrs of the National Health and Nutrition Survey 4th in year of 2009, which includes symptoms of temporomandibular disorder within gender and age. Subjects included in this study were 2,738 males and 3,427 females, total of 6,165. All statistical analysis was measured by Window SPSS 17.0K Program (SPSS Inc., Chicago, USA). Prevalence of analysis of gender, age, and symptoms of temporomandibular disorder was measured by descriptive statistics, and in order to find relationship among gender, age, and symptoms of temporomandibular disorder was based on crosstabulation analysis. As results, prevalence of TMJ sound was 10.1%, of TMJ pain was 1.5%, and of TMJ limitation was 2.0%. Among the three symptoms of temporomandibular disorder, subjects who have at least one symptom was 1.2%. Prevalence of TMJ sound, of TMJ pain, and of TMJ limitation in female were 10.7%, 1.8% and 2.2%, respectively, which were greater than in male 9.3%, 1.2% and 1.6% respectively but it was stastically insignificant (p>0.05). Prevalence of TMJ sound, of TMJ pain, and of TMJ limitation in ages between 19~24 yrs were 18.7%, 3.4% and 4.2% respectively, which were higher than any other ages (p<0.05). Also prevalence of having at least one symptom of temporomandibular disorder, at least two, and three all were higher in females but stastically insignificant (p>0.05). On the other hand, prevalence of having at least one symptom of temporomandibular disorder, at least two, and three all were greater in age below 45 yrs and was stastically significant (p<0.05).

A Descriptive Statistical Analysis of the Hospitalized Patients with Low Back Pain in Departments of Korean Rehabilitation Medicine of Korean Medicine Hospitals (한국의 5개 한의과대학 부속한방병원 재활의학과의 요통 입원 환자에 대한 후향적 기술통계분석 - 입원 기간, 상병명, 치료 방법을 중심으로 -)

  • Maeng, Tae-Ho;Kim, Jongyeon;Yi, Woon-Sup;Chung, Won-Seok;Ko, Youn-Seok;Lee, Jung-Han;Shin, Byung-Cheul;Cha, Yun-Yeop;Go, Ho-Yeon;Sun, Seong-Ho;Jeon, Chan-Yong;Jang, Bo-Hyoung;Song, Yun-Kyung;Ko, Seong-Gyu
    • Journal of Korean Medicine Rehabilitation
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    • v.23 no.4
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    • pp.213-223
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    • 2013
  • Objectives Low back pain (LBP) is one of the most common reason for people in Korea to visit Korean medical institutions. To assess actual amounts of use in the treatment of LBP in Korean medicine and to provide objective base line data for policy decision making, research regarding the current state of LBP patients' treatment in Korean medical institutions are in need. Methods The current study was designed as a retrospective chart review to investigate descriptive characteristics of LBP patients. The clinical records of 304 patients who were hospitalized for the treatment of LBP in Korean rehabilitation medicine inpatient clinics of five different Korean medicine hospitals were analyzed. The percentage of patient characteristics such as sex, age, average duration of admission, insurance type, diagnosed LBP related disease code, and rates of interventions applied were assessed. Results 1. The female sex was significantly predominant among patients with LBP : 105 patients (34.5%) were male and 199 patients (65.5%) were female. Percentage of the patients' age appeared as followed : 76 people (25.0%) were in their 50s, 64 people (21.1%) were in their 40s, 51 people (16.8%) were in their 30s, 37 people (12.2%) were in their 60s, and 33 people (10.9%) were in their 70s. Approximately half of the total LBP patients investigated were older than 50. 2. The average duration of admission was 16.2 days. Approximately one third (30.3%) of the patients were hospitalized for 8 to 14 days. 3. Female patients tended to stay admitted in hospitals slightly longer than male patients. Elderly (age 60~79) patients stayed in hospitals longer (17.8 days) compared to younger (age 20~39) patients (13.5 days). 4. More than half of the patients (171 cases, 56.3%) had their hospital bills covered with automobile insurance. 40.1% (122 cases) of the patients had medical insurance to cover their hospital bills. The average duration of admission of patients who had automobile insurance was 14.2 days, while that of the patients who had medical insurance was 18.4 days. 5. "Sprain and strain of the lumbar spine and pelvis" was the most commonly used (195 cases, 64.1%) disease code in patients with LBP. Patients diagnosed as "lumbar and other intervertebral disc disorders with radiculopathy" required the longest admission duration (22.1 days). 6. Herbal medication was applied to all of the patients during admission. Acupuncture was applied to all of the patients except one case diagnosed as spinal stenosis. Physical therapy, cupping therapy, moxibustion therapy, chuna therapy, and pharmacopuncture therapy were applied to 94.7, 92.8, 85.2, 83.9, and 49.7% of the patients, respectively. 7. There were certain differences among Korean medicine hospitals in terms of the LBP patients' duration of admission, type of insurance, frequency of the disease code use, type of intervention applied. Conclusions It is thought that the current study can be used as reference data in assessing the current state of LBP treatment in Korean rehabilitation medicine and a basis for future research. Provided improvements of certain limitations of the current study in future researches, such data would act as better base line data in policy decision making.

Analysis of Linkage between Official Development Assistance (ODA) of Forestry Sector and Sustainable Development Goals (SDGs) in South Korea (국내 임업분야 공적개발원조(ODA)사업과 지속가능발전목표(SDGs)와의 연관성 분석)

  • Kim, Nahui;Moon, Jooyeon;Song, Cholho;Heo, Seongbong;Son, Yowhan;Lee, Woo-Kyun
    • Journal of Korean Society of Forest Science
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    • v.107 no.1
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    • pp.96-107
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    • 2018
  • This study analyzed the linkage between the Forestry sector Official Development Assistance (ODA) Project in South Korea and the Sustainable Development Goals (SDGs) of United Nations (UN), Suggested direction of ODA project focusing on the implementation of the SDGs. Forestry sector ODA project data in South Korea have collected from Economic Development Cooperation Fund (EDCF) statistical inquiry system developed by The Export-Import Bank of Korea. According to the analysis result, Forestry sector ODA project in South Korea have been actively implemented in the fields of forestry development, forestry policy and administration. In both fields, Korea Forest Service and Korea International Cooperation Agency (KOICA) carried out the most projects. The Forestry sector ODA project data in South Korea are classified technical development, capacity building, construction of infrastructure and afforestation based on their objectives and contents. SDGs emphasizes the importance of national implementation assessment and this study analyze linkage between ODA activity content in each classification item and 2016 Korea Forest Service Performance Management Plan indicator. Analyzed the 2016 Korea Forest Service Performance Management Plan indicator and SDGs target and SDGs indicator were identified. finally, SDGs goals were recognized. In conclusion, Forestry sector ODA project in South Korea are associated with the SDGs Goal 1 (No Poverty), Goal 2 (Zero Hunger), Goal 6 (Clean Water and Sanitation), Goal 13 (Climate Action), Goal 15 (Life on Land) and Goal 17 (Partnership for The Goals). Therefore, With the launch of the SDGs, This study analyzed the linkage among the Forestry sector ODA Project in South Korea, the 2016 Korea Forest Service Performance Management Plan and the SDGs. it presented the limitations of Forestry sector ODA Project in South Korea and made proposals for the implementation of the SDGs.

Effects of Strength Recognition on the Intent of Start-up after Retirement: To the Office Workers (강점인식이 은퇴 후 창업의도에 미치는 영향: 직장인을 대상으로)

  • Park, Hye sung;Park, Woojin;Yun, Bae byung
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.15 no.1
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    • pp.143-150
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    • 2020
  • This research is intended to identify how office worker's recognition of strength affects the intention of starting a business when it is used as a medium for utilizing strength. The survey period was conducted for two months from January 17, 2019 to March 8, 2019. In order to achieve the object of this study, a significant number of employees have been collected nationwide, and 287 office workers were analyzed after collecting 300 questionaires, excluding 13 office workers who were not sincere. The significant data were analyzed by utilizing the structural equation and technical statistics and by verifying the conformity of structural model and measurement model and by investigating the relationship between variables. The results of this study are summarized as follows: First, employee's perception of strength has been found to have a significant effect on the utilizing of strength. Second, the use of workers' strengths has been found to have a significant effect on the intention of starting a business. Third, it has been confirmed that in the relationship between the employee's perception of strength and intention to start a business, the recognition of strength has a significant effect on the intention of starting a business only through the use of strength. Most office workers are nervous about the future and make various plans. The time to live after retirement is getting longer and jobs and working hours are shrinking at an alarming rate. According to the analysis on the status of small business owners in the mid-term of 2017 data, the average monthly operating profit of small business owners across the country is decreasing over the years, and most start-ups are subsistence-type start-ups, and they decide to start their own businesses because they have no other choice than start-ups. As the number of small business owners suffering from financial difficulties has increased since the financial crisis and insecurity of job is pushing those with financial difficulties after retirement to the battleground of the start-up market, the result of this research suggest that the workers need to recognize their own strength and enhance the importance of utilizing the strength.

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.