• Journal of the Korean Operations Research and Management Science Society
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• v.17 no.3
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• pp.101-135
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• 1992

An an exploratory attempt, this study examines the patterns of strategic changes of the firms and changes in strategic group structure in response to environmental changes of the industry. Empirical analyses of 39 firms in the Korean tile industry for the period of 1986-1990 reveals that :1) environmental changes had different impacts on attractiveness of different product/market segments :2) the relatively large firms in less attractive product/market segments were more likely to change their domains :3) according to their specific target product/market segments, the firms tended to strengthen different resource capabilities which were identified as key success factorss to compete in each target segment : and 4) these differences in strategic changes of the firms resulted in the changes in strategic group structure during the same period. Implications and the limitations of this study are finally discussed.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.765-768
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• 2004

This study reports the site application of the early strength development technology for form stripping earlier than normal state in the apartment construction. It is a method of framework rationalization and it needs the technology of early strength development concrete and 6-day cycle process. We applied the method to the apartment construction to reduce the floor construction period and to maximize the economical effect by reduction of the period of total construction. As a result, we confirmed the superior property of the early strength development of the concrete and reliable success of 6-day cycle process.

• The Journal of the Korean dental association
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• v.49 no.4
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• pp.211-218
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• 2011

Purpose: An impacted tooth is defined as a tooth that shows delayed eruption and is expected to erupt incompletely by clinical and radiograph examination despite it reaching its expected time of eruption. The aims of this study were to investigate the clinical and radiological characteristics and treatment duration and method of impacted teeth in Korean patients. Materials and Methods: For this study we used clinical records, study models, panoramic radiographs and intraoral photographs of patients who attended Gachon University Gil Hospital Orthodontic Department between 2005 and 2008. There were 164 patients with a total number of 202 impacted teeth. Results: Male patients shows a little more prevalence than female patients (1.13:1). The under 12 age group had the highest prevalence of tooth impaction, and the over 19 age group showed the least prevalence of tooth impaction. The ratio of tooth impaction between the left to right ratio was 1.73:1 and maxilla and mandible was 1.84:1. The impacted teeth were most commonly positioned buccally (76 cases, 41.5%). Full nap closure technique (108 cases, 81.2%)was most frequently used for attachment of surgical traction hooks. Maxillary canine impaction was most commonly encountered both in male and female patients. The mean treatment period was 12.2 months and the success rate of treatment was 90.3%. The canine tooth shows the longest treatment time and highest failure rate. The ankylosis was the major cause of failure. Conclusion: Impacted teeth most commonly show in left side maxilla in the under 12 age group. And it is most commonly positioned buccally. The mean treatment period was 12.2 months, and the success rate of treatment was 90.3%.

• Ocean and Polar Research
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• v.39 no.4
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• pp.257-267
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• 2017

Although Pacific mackerel (Scomber japonicus) is an important commercial species in Korea, its recruitment mechanism remains largely unknown. Diel vertical positioning of larvae in the water column, which is affected by their specific gravity and the surrounding water density, may help to provide an understanding on recruitment success through predator avoidance and prey availability. The specific gravity measurement on Pacific mackerel eggs and larvae would seem to be essential information necessary to learn about the transport process from spawning to nursery grounds, and consequently the recruitment success. Eggs were artificially fertilized, and larvae were fed with rotifer when their mouths opened 3-4 days after hatching. We conducted the experiment using a density gradient water column to measure the ontogenetic changes in specific gravity from fertilization to 10 days after hatching. Egg specific gravity was stable during most of the embryonic period, but a sudden increase to $1.0249g\;cm^{-3}$ happened just before hatching. However, the specific gravity of newly hatched larvae was much lighter ($1.0195g\;cm^{-3}$), and specific gravity tended to increase continuously after hatching. Comparison of specific gravity with seawater density reveals that eggs and newly hatched larvae can float in the surface layer of the ocean. For the later period of the experiment, the specific gravity showed a cyclic diel pattern: the highest in the evening while the lowest at dawn. The fullness of larval stomach may be responsible for the observed differences in specific gravity, because stomach fullness was lower (40-60%) at midnight, and higher (80-85%) in evening. The diel pattern of specific gravity might provide clues regarding how larvae match the diel vertical migration of prey organisms.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.10b
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• pp.2-3
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• 2003

A method for rapid propagation of mature Jack fruit was developed. Four types of explants (mature embryos, apical meristems of young seedlings, apices from mature plants and nodal segments) were used. It has been found 88% of young apical meristems produced shoots in Campbell and Durzan (CD) medium compared to 60% in Murashige and Skoog (MS) medium. Only 1/3 of them produced multiple shoots. Shoot initiation from nodal segments was very rare. Mature apices produced callus. Although removal of the sheathing cover around mature buds enhanced the shoot initiation but success rate was low in growth regulator free medium. Embryos respond to the CD medium but not to the MS medium. Embryos from seeds soaked in water for 24 hours produced shoots after 8 weeks of incubation and the success rate was 70% while embryos from dry seeds only produced roots. There was no significant effect of cold storage (refrigeration) for 7 days on shoot initiation from mature embryos (65%) but the ability for shoot induction declines with storage time (55% after 21 days of cold storage). Mature axillary buds were established in Modified Campbell and Durzan (CD) medium supplemented with 0.5mg/1 and IBA. There was a significant difference in the growth performance of shoots according to the period of the year in which explants were collected. Highest (60%) was observed in November-January period. It was only 30% when the explants were collected in February-April or May-July and decreased to 20% in August-October. The shoots produced in November-January showed a higher vigor than those produced in other months. Since Jak fruit show seasonal changes in fruit bearing and shedding of leaves, it can be suggested that the difference in growth performances of tissues cultured in artificial culture media would have been affected by endogenous rhythms.

• The Journal of Korean Obstetrics and Gynecology
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• v.23 no.3
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• pp.173-183
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• 2010

Purpose: To estimate the effect of oriental treatment on recurrent pregnancy loss, a retrospective analysis was done. Methods: Sixty-eight pregnant women at the $\bigcirc\bigcirc$ oriental clinic, Korea, from January 2005 to May 2009 diagnosed as recurrent pregnancy loss were included in this study. The sixty-eight patients received oriental treatment such as acupuncture, moxibution, herbal acupuncture and herbal prescriptions, divided into two groups: Group A- live birth(N=58) and Group B- abortion(N=10). The maternal age, parity, menstrual history, gynecological history and period of treatment were compared. To find out factors affecting the success of birth, we performed binary logistic regression analysis(SPSS ver. 14.0 for windows). Results: The live birth rate was 85.3%. The maternal age, parity, menstrual history, gynecological history and period of treatment were not different between two groups. Logistic regression analysis showed that the significant factors predicting the occurrence of miscarriage were advanced maternal age(${\geq}35$)(P=0.005, Odds Ratio[OR]=3.809, 95% Confidence Interval[95%CI]: 1.514-9.585) and suffering from gynecological problems(P=0.044, OR=4.048, 95%CI: 1.037-15.801). Conclusions: The results suggest that oriental treatment has effectiveness on recurrent pregnancy loss. Further study will be needed.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.10a
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• pp.9-18
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• 2003

A method for rapid propagation of mature Jack fruit was developed. Four types of explants (mature embryos, apical meristems of young seedlings, apices from mature plants and nodal segments) were used. It has been found 88% of young apical meristems produced shoots in Campbell and Durzan (CD) medium compared to 60% in Murashige and Skoog (MS) medium. Only 1/3 of them produced multiple shoots. Shoot idtiation from nodal segments was very rare. Mature apices produced callus. Although removed of the sheathing cover around mature buds enhanced the shoot initiation but success rate was low in growth regulator free medium. Embryos respond to the CD medium but not to the MS medium. Embryos from seeds soaked in water for 24 hours produced shoots after 8 weeks of incubation and the success rate was 70% while embryos from dry seeds only produced roots. There was no significant effect of cold storage (refrigeration) for 7 days on shoot initiation from mature embryos (65%) but the ability for shoot induction declines with storage time (55% after 21 days of cold storage). Mature axillary buds were established in Modified Campbell and Durzan (CD) medium supplemented with 0.5mg/1 and IBA. There was a significant difference in the growth performance of shoots according to the period of the year in which explants were collected. Highest (60%) was observed in November-January period. It was only 30% when the explants were collected in February-April or May-July and decreased to 20% in August-October. The shoots produced in November-January showed a higher vigor than those produced in other months. Since Jak fruit show seasonal changes in fruit bearing and shedding of leaves, it can be suggested that the difference in growth performances of tissues cultured in artificial culture media would have been affected by endogenous rhythms.

• Clinical and Experimental Pediatrics
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• v.61 no.12
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• pp.397-402
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• 2018

Purpose: Transcatheter device closure of patent ductus arteriosus (PDA) is challenging in early infancy. We evaluated PDA closure in infants less than 6 months old. Methods: We performed a retrospective review of infants less than 6 months of age who underwent attempted transcatheter device closure in our institution since 2004. To compare clinical outcomes between age groups, infants aged 6-12 months in the same study period were reviewed. Results: A total of 22 patients underwent transcatheter PDA closure during the study period. Patient mean age was $3.3{\pm}1.5months$, and weight was $5.7{\pm}1.3kg$. The duct diameter at the narrowest point was $3.0{\pm}0.8mm$ as measured by angiography. The most common duct type was C in the Krichenko classification. Procedural success was achieved in 19 patients (86.3%). Major complications occurred in 5 patients (22.7%), including device embolization (n=1), acquired aortic coarctation (n=2), access-related vascular injury requiring surgery (n=1), and acute deterioration requiring intubation during the procedure (n=1). Two patients had minor complications (9.1%). Twenty-four infants aged 6-12 months received transcatheter device closure. The procedural success rate was 100%, and there were no major complications. The major complication rate was significantly higher in the group less than 6 months of age (P=0.045). There was a trend toward increased major complication and procedural failure rates in the younger age group (P<0.01). Conclusion: A relatively higher incidence of major complications was observed in infants less than 6 months of age. The decision regarding treatment modality should be individualized.

• Parasites, Hosts and Diseases
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• v.61 no.2
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• pp.103-126
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• 2023

In the l950s, under the legacy of traditional agriculture, Ascaris lumbricoides, spread epidemically in the war-bitten society of Korea. Consensus on the parasite control was drafted in the Parasite Disease Prevention Act, which passed a parliamentary agreement in 1966, and established safe disposal of feces and mass chemotherapy as control strategies. Biannual stool examinations and treating infected schoolchildren were basic scheme of the control activity through which revenue could be secured for organized business. In the 27 years following 1969, a maximum of 16 million stool examinations had been done every year. Cellophane thick smear enabled the task. The infection declined remarkably in the 1970s when industrialization and green revolution proceeded. A population study of A. lumbricoides in the late 1970s helped us better understand its epidemiology. The data also settled down the understandable protest of teachers against the repeated stool examinations. In the 9 years following 1987, the target population was gradually reduced when the egg positive rate was below 0.1%. An article in the Korean Law, stipulating obligatory stool examinations, was made optional. Although the long-term Korean effort of Ascaris control was a success, the effect of mass chemotherapy was not as succinct in terms of lowering reinfection. In the period of control, Korean agricultural technology changed, and the economy grew and supplied sanitary facilities by which the vicious cycle was disconnected. Reduction of morbidity was a benefit of mass chemotherapy, which is the only control method feasible in economically difficult countries. The most important hurdle of parasite control in the 1960s was poverty of general population and limited financial resources in Korea but the society formed a consensus on the priority of intestinal helminthiasis control during the ordeal period. The national consensus in the 1960s was the critical milestone for Ascaris control in Korea. Under the social agreement, application of timely technical and research advancements in parasitology achieved the success of ascariasis elimination. The successful experience of ascariasis elimination in Korea can be a benchmark for countries where neglected tropical diseases are endemically recycled.

• Fashion & Textile Research Journal
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• v.9 no.6
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• pp.603-612
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• 2007

Giorgio Armani has made a huge success with his own persistent unique fashion styles for the last 30 years. But he too went through a transitional period during which he was criticized for lacking the so-called Armani design. Overcoming the confusion, however, he succeeded in recreating his styles of elegant image and fascinating people with his practical and yet sophisticated modern classical styles that he pioneered. The design characteristics of his men's clothing are as follows; functional and comfortable slim silhouettes that bring life to the curves of the human body, grey-based mixed colors in a natural atmosphere, natural materials such as wool, silk, and cashmere that are light and soft and have great drape properties with femininity, solid patterns with stripes, checks, and geometrical figures added, and the elegance expressed in moderate decorations such as a handkerchief and scarf. Armani men's clothing has enjoyed ongoing popularity and success across the world because it transcends time and allows men to maintain their class not being bound by the formality. It's also important to notice that Armani takes into account the perspectives of both men who wear his clothes and women who look at the men in his clothes.