• Steel and Composite Structures
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• v.23 no.3
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• pp.273-283
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• 2017

In this paper, it is aimed to present a detail investigation related to structural behavior of laterally unrestrained steel cantilever roof of tribune with slender cross section. The structure is located in Tutak town in $A{\breve{g}}r{{\i}}$ and collapsed on October 25, 2015 at eastern part of Turkey is considered as a case study. This mild sloped roof structure was built from a variable I beam, and supported on steel columns of 5.5 m height covering totally $240m^2$ closed area in plan. The roof of tribune collapsed completely without any indication during first snowfall after construction at midnight a winter day, fortunately before the opening hours. The meteorological records and observations of local persons are combined together to estimate the intensity of snow load in the region and it is compared with the code specified values. Also, the wide/thickness and height/thickness ratios for flange and web are evaluated according to the design codes. Three dimensional finite element model of the existing steel tribune roof is generated considering project drawings and site investigations using commercially available software ANSYS. The displacements, principal stresses and strains along to the cantilever length and column height are given as contour diagrams and graph format. In addition to site investigation, the numerical and analytical works conducted in this study indicate that the unequivocal reasons of the collapse are overloading action of snow load intensity, some mistakes made in the design of steel cantilever beams, insufficient strength and rigidity of the main structural elements, and construction workmanship errors.

• The Korean Journal of Community Living Science
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• v.15 no.2
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• pp.55-64
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• 2004

The purpose of this study was to examine the differences in skin temperature and thermal comfort of participants in a $19^\circ{C}$ room (the recommended room temperature in the winter) depending on age, sex and clothing weight. Subjects were divided into four groups (6 young males, 5 young females, 6 old males, 6 old females) and experimental trials consisted of three conditions: wearing underwear in a $19^\circ{C}$ room (19CUW), without underwear in a $19^\circ{C}$ room (19C), and without underwear in a $24^\circ{C}$ room (24C). The results indicated the following: 1) There were no significant differences in mean skin temperature based on age or sex, and the mean skin temperatures of the four groups were in the range of 32.4∼$34.0^\circ{C}$. 2) In the 19C condition, the skin temperatures of the hands and feet of old females were higher than those of the other three groups. 3) In terms of perceived thermal comfort, young females showed a tendency to feel the most uncomfortable. Both old and young groups agreed that the 24C condition was the most comfortable. 4) Relational coefficients between thermal comfort and skin temperatures were higher in the young group than in the old group. Furthermore, the perceived thermal comfort had a stronger relationship with mean skin temperatures than with local skin temperatures. 5) The mean skin temperatures of subjects who indicated they were 'comfortable' were in the range of 31∼$36^\circ{C}$ regardless of age or sex.

• Journal of the Korean Geographical Society
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• v.43 no.4
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• pp.495-510
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• 2008

Vaccinium vitis-idaea or lingonberry, a typical arctic-alpine plant, is common on the circumpolar regions and alpine belts of the Northern Hemisphere, and also occurs on the alpine and subalpine belts of the Korean Peninsula, including Mt. Sorak and Hongchon. Vaccinium vitis-idaea at the elevation of c. 350m a.s.l. of Hongchon is found on the wind hole area with cool summer, and mild winter. Vaccinium vitis-idaea at Hongchon is regarded as the glacial relict of the Pleistocene period, and shows a disjunctive distribution, along with the alpine and subalpine belts of the northern and central Korea since the Holocene period. Present vertical range of Vaccinium vitis-idaea between Mt. Sorak and Hongchon might indicates that the temperatures during the glacial epoch was colder than today, down to -6 to $-7^{\circ}C$ Vaccinium vitis-idaea at this fragile wind hole site could be endanger if current global warming trends continues, and anthropogenic activities become serious.

• Korean Journal of Medicinal Crop Science
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• v.26 no.5
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• pp.401-407
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• 2018

Background: In Korea, seeds of Panax ginseng C. A. Meyer need to be stored under cold temperature and high humidity condition for months to break physiological dormancy, making storage difficult until spring-sowing. This study was conducted to test the effects of seed storage conditions and seed treatment on the emergence of seedling after spring-sowing in a nursery greenhouse. Methods and Results: After dehiscence, endocarp dried seeds in mild or completely, and wet seeds were stored in $2^{\circ}C$ and $-3.5^{\circ}C$ during winter. Storage at $-3.5^{\circ}C$ resulted in a lower emergence rate (ER) than that at $2^{\circ}C$, and additional cold ($2^{\circ}C$) treatment before or after storage at $-3.5^{\circ}C$ increased the ER. Endocarp dehydration prevented pre-germination at $2^{\circ}C$ storage and increased the ER of seeds stored at $-3.5^{\circ}C$. ER was also dependent on the batch of seeds. However, seed treatments before sowing had only limited effects on ER. Root loss was the main reason for damping-off; prolonged cold storage of seeds increased damping-off, as the detection of pathogens was not high. Conclusions: This study showed that storage conditions such as temperature and moisture content of seeds, affect the ER after spring-sowing and vitality of seedlings, suggesting further attention on seed control for secure seedling stands after spring-sowing.

• Sleep Medicine and Psychophysiology
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• v.5 no.2
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• pp.170-176
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• 1998

Nowadays light therapy is accepted practice in the treatment for Seasonal Affective Disorder. The author reviewed the practical aspects of light therapy, latest treatment research on optimal parameters of light therapy and the mechanisms of action of light therapy. Therapeutic efficacy of light therapy using light visors & dawn simulators has been suggested but further studies are needed to clarify the efficacy. The treatment most strongly supported by research studies is light therapy using a light box to administer bright white light (2500 lux for 2 hours or 10000 lux for 30 minutes). Although some patients may be selective responders to morning light exposure, the optimal timing of light exposure still remains controversial. In practice, generally the duration of exposure can be increased or decreased as necessary and also the timing of exposure can be splitted (e.g. AM/PM usage) if optimal response is obtained. For most, a positive response of light therapy is usually noted within $4{\sim}5\;days$ and optimal response is obtained within 2 weeks. Generally the relapse of symptom occurs within days of discontinuation of light therapy, so to prevent relapse, light therapy should be continued throughout the winter season for typical seasonal affective disorder. Side effects of light therapy appear to be mild and well tolerated. Several theories for the mechanisms of action of light therapy at the basis of seasonal affective disorder had been suggested but remain still controversial. Further studies on the optimal parameters and the mechanisms of light therapy help us to better understand and treat not only seasonal affective disorders but also chronobiological disorders and nonseasonal affective disorders.

• Korean Journal of Veterinary Research
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• v.22 no.1
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• pp.53-58
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• 1982

Stomachs from 3,354 fattening pigs were examined at slaughter during the period from September 1980 to August 1981. Pigs of both sexes and $Landrace{\times}Hampshire$ crossbreds were included in the present studies, and they weighed about 60-120kg. Gross pathologic alterations of the stomach were classified as normal, epitnelial change, erosion, ulcer and scar formation. Representative tissue sections were taken from the stomach lesions at random and fixed in 10% buffered formalin. Cut sections were stained with hematoxylin and eosin, and examined histopathologically. The results obtained in the present studies were as follows. 1. In the seasonal prevalence of gastric ulceration, severe ulceration with erosion was shown during the Autumn and Winter, whereas mild ulceration was mainly shown during the Spring and Summer. 2. Of the 3,354 stomachs of the pigs, 20.8% were found to be normal. Of the rest, 40% had epithelial changes, followed by erosion (24.7%), ulcer (13.6%) and scar formation (0.9%), respectively. 3. In the prevalence of ulcers in the different regions of the stomach, the fundic region had the highest rate (61.6%) of ulceration, followed by cardiac (21.7%), esophageal (15.0%) and pyloric region (1.7%). 4. The principal gross changes were severe epithelial changes with keratotic proliferation in the esophageal region, and in the fundic region severe folding of the stomach wall was covered with bloody mucous exudates. 5. Main histopathological changes were inflammatory cell infiltrations in most cases, hemorrhages in acute ulcers and prominent proliferation of granulation tissues in chronic ulcers.

• Journal of Environmental Impact Assessment
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• v.20 no.3
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• pp.381-395
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• 2011

Present work aims to establish an integrated management system of environmental data base for nine typical wind holes or air holes in Korea. It basically deals with definition, geographical distribution, morphological pattern, physical characteristics and anthropogenic environments of wind hole to propose systematic preservation strategy of their periglacial landscape and flora, which are known to be sensitive to global warming. Wind hole, in which cool air blows out during the summer, but mild air comes out during the winter from a cave or hole, is frequently found on northwest- and north-facing slopes on the terminal point of steep talus, block field, and block stream, and can be categorized into three types, i.e., talus, cave and sink types. Environmental characteristics of nine wind holes are analyzed on the basis of their geology, landform, climate, soil, hydrology, vegetation, road, footpath, land-use, and management system, and relevant DB are prepared. Wind hole areas with unique landscape and ecological values need to be designated as a nature reserve, and zoning of core, buffer, and transitional zones are required for the multi-dimensional preservation of periglacial landscape and ecosystem. Phytogeographical values of glacial relict plants, including mountain cranberry(Vaccinium vitis-idaea) at its global southernmost limit at Bangnaeri wind hole, Hongchon County, Gangwon Province of Korea are discussed in detail as a floristic refugia in connection with climate change during the Pleistocene Epoch and potential in-situ and ex-situ preservation sites in the future.

• Korean Journal of Veterinary Service
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• v.22 no.4
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• pp.325-347
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• 1999

This study was conducted to investigate the epidemiological, clinicopathological, microbiological, pathological observations and other tests from sudden death in feedlot cattle at the region of Sarari in Korea during the period from 1994 to 1999. Massive or sporadic occurrence of sudden death has been observed in 101 heads of 47 farmhouse. There were 20.8% in spring, 29.7% in summer, 16.8% in autumn, 32.7% in winter, and 62.3% in reproductive, 27.7% in growing, 5.0% in beef cattle, 5.0% in calf in prevalence of sudden death in cattle. Enterotoxemia(88.0%), pneumonia(3.5%), intestinal diarrhea(3.5%), liver abscess(1.5%) and indigestion(1.5%) were detected from 67 heads of sudden death cattle. In clinical observations, cattle were generally died of sudden recumbency with convulsions followed anorexia, depression, ataxia, muscular tremor, tachycardia and dyspnea without any premonitory symptoms. Epidemiological surveys showed no evidence that other factors such as pesticide, insecticide, fertilizer, chemical drug3 and those of others caused sudden death. Macroscopically, there were coagulation disorders of blood, congestion, edema and haemorrhage of lung, congestion and haemorrhages, watery and blood-tinged contents of small intestine. Histopathologically, we observed pulmonary congestion and haemorrhage, necrotic intestinal mucosa accompanied with haemorrhage and congestion, and also increased globule leukocytes between bronchial epithelia with mild pneumonia. Clinicopathologically, only elevation of blood glucose and aspartate aminotransferase(AST) was detected. Magnesium and calcium deficiency were not detected, but parasites were detected highly in normal and dead cattles. Microbiologically, Clostridium(Cl) pefringens were detected from small intestinal contents of 94% (63/67) of sudden death cattle and 51%(51/101) of slaughter cattle, and the population were $10^{6-8}$/cfu/$m\ell$ after 16~32 hours. Consequently, it was proved that the cause of death in cattle was enterotoxemia. Pathogenic test of mouse and goat inoculated with Cl perfringens type A toxin has been demonstrated as similar observation to natural cases. In antimicrobial susceptibility test, ampicillin, bacitracin, polymycin, cephalothin, penicillin, choramphenicol, erythromycin, tetracycline were highly susceptible, and amikacin, gentamicin, kanamycin, neomycin, streptomycin, sulfamethoxine, sulfamethazine were resistant. Cl perfringens were resisted for 4 hours in 3% formalin, 20 minutes in 4% phenol, 20 minutes in 0.5% mercuric chloride and 40 minutes in 0.1% sodium hydroxide, respectively. The useful method to prevent from occurrance of enterotoxemia in feedlot cattle was a dietary administration of antibiotics and miyari acid.

• The Journal of Korean Physical Therapy
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• v.11 no.1
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• pp.23-43
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• 1999

A study on severity of cerebro-vascular accident patients in Korea was conduced in order to determine the risk factors affecting the severity of stroke patients. This study was performed by interviewing a total of 477 hospitalized and ambulatory patient of CVA in Seoul, Taejon, and Taegu and Pusan areas from April 1, 1998 through June 30, 1998. The results are as follows; 1. Two hundred and sixty seven $(56\%)$ at Four hundred and seventy seven subjects were manes, md two hundred and ten $(44\%)$ were females. $28.3\%$ of the subjects' ages were 50's and $27.3\%$ were 60's and $18.5\%$ were 70's. $22.6\%$ of the subjects' occupations were home makers, $17.8\%$ were farming. $66.4\%$ of the subjects spent their childhood in urban areas and $33.1\%$in rural areas. $41.7\%$ of the subjects became violin of CVA in Spring, $35.0\%$ in Winter. 2. On physical and mental conditions of the subjects at the occurrence of CVA, $28.7\%$ of the subjects were engaged in physical activities. $22.6\%$ were in a rest stale $19.5\%$ were in sleeping and $18.9\%$ were mentally shocked. $79.4\%$ of the male subjects and $14.8\%$ of female subjects smoked cigarettes. $82\%$ of male subjects drank coffee. $81.1\%$ of the subjects did not exercise regularly. $45.9\%$ of the subjects had the systolic blood pressures in the range of 160 to 199 mmHg and $5.6\%$ of the subjects had hypertension before the occurrence of stroke and $11.7\%$ had diabetes. 3. Of the types of strokes, cerebral hemorrhage was the highest $(49.1\%)$. cerebral infarction was the second $(41.1\%)$. Severe strokes were found in cerebral hemorrhage cases $(52.0\%)$ and cerebral infarction cases $(40.1\%).\;50.9\%$. of the male subjects were moderate cases, $50.9\%$ were severe cases. In females, moderate cases were $72.4\%$, severe cases $15.2\%$. $37.5\%$ of the subjects who had preceding diseases were severe cases, and $15.6\%$ of the subjects without preceding diseases were severe cases. $50.7\%$ of the subjects whose family members had strokes had severe strokes. $34\%$ of the subjects sleeping less than 6 hours a day, $42.4\%$ of the subjects with irregular eating habits, $33.3\%$ of the subjects who liked meat, and $42.3\%$ of the subjects who liked salty foods had severe strokes. $35.9\%$ of the subjects with hot temper, $27.6\%$ of the subjects with moderate temper and $14.5\%$ of subjects with mild temper were severe cases. 4. The correlation coefficient between obesity and blood pressure was 0.094.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.5
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• pp.657-664
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• 2019

Objective: This study was performed to evaluate whether cold ambient temperature and dietary rumen-protected fat (RPF) supplementation affect growth performance, rumen fermentation, and blood parameters in Korean cattle steers. Methods: Twenty Korean cattle steers (body weight [BW], $550.6{\pm}9.14kg$; age, $19.7{\pm}0.13months$) were divided into a conventional control diet group (n = 10) and a 0.5% RPF supplementation group (n = 10). Steers were fed a concentrate diet (1.6% BW) and a rice straw diet (1 kg/d) for 16 weeks (January 9 to February 5 [P1], February 6 to March 5 [P2], March 6 to April 3 [P3], and April 4 to May 2 [P4]). Results: The mean and minimum indoor ambient temperatures in P1 ($-3.44^{\circ}C$, $-9.40^{\circ}C$) were lower (p<0.001) than those in P3 ($5.87^{\circ}C$, $-1.86^{\circ}C$) and P4 ($11.18^{\circ}C$, $4.28^{\circ}C$). The minimum temperature in P1 fell within the moderate cold-stress (CS) category, as previously reported for dairy cattle, and the minimum temperatures of P2 and P3 were within the mild CS category. Neither month nor RPF supplementation affected the average daily gain or gain-to-feed ratio (p>0.05). Ruminal ammonia nitrogen concentrations were higher (p<0.05) in cold winter than spring. Plasma cortisol concentrations were lower (p<0.05) in the coldest month than in the other months. Serum glucose concentrations were generally higher in colder months than in the other months but were unaffected by RPF supplementation. RPF supplementation increased both total cholesterol (p = 0.004) and high-density lipoprotein (HDL) concentrations (p = 0.03). Conclusion: Korean cattle may not be significantly affected by moderate CS, considering that the growth performance of cattle remained unchanged, although variations in blood parameters were observed among the studied months. RPF supplementation altered cholesterol and HDL concentrations but did not affect growth performance.