• Journal of Korean Society of Steel Construction
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• v.27 no.6
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• pp.513-523
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• 2015

In steel moment frames constructed of H-shapes, strong-axis moment connections should be used for maximum structural efficiency if possible. And most of cyclic seismic testing, domestic and international, has been conducted for strong-axis moment connections and cyclic test data for weak-axis connections is quite limited. However, when perpendicular moment frames meet, weak-axis moment connections are also needed at the intersecting locations. Especially, both strong- and weak-axis moment connections have been frequently used in domestic practice. In this study, cyclic seismic performance of RBS (reduced beam section) weak-axis welded moment connections was experimentally investigated. Test specimens, designed according to the procedure proposed by Gilton and Uang (2002), performed well and developed an excellent plastic rotation capacity of 0.03 rad or higher, although a simplified sizing procedure for attaching the beam web to the shear plate in the form of C-shaped fillet weld was used. The test results of this study showed that the sharp corner of C-shaped fillet weld tends to be the origin of crack propagation due to stress concentration there and needs to be trimmed for the better weld shape. Different from strong-axis moment connections, due to the presence of weld access hole, a kind of CJP butt joint is formed between the beam flange and the horizontal continuity plate in weak-axis moment connections. When weld access hole is large, this butt joint can experience cyclic local buckling and subsequent low cycle fatigue fracture as observed in this testing program. Thus the size of web access hole at the butt joint should be minimized if possible. The recommended seismic detailing such as stickout, trimming, and thicker continuity plate for construction tolerance should be followed for design and fabrication of weak-axis welded moment connections.

• Journal of dental hygiene science
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• v.11 no.3
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• pp.265-272
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• 2011

The purpose of this study is to compare oral hygiene status between young adult group and older adult group and to suggest a pathway model of oral health level in self-assessed. Subjects were totally 80 people with young adult group and the older adult group. The data, which was collected by surveying for one month from July 1, 2010 to July 30, was analyzed with SPSS VERSION 19.0 and AMOS 19.0. Oral hygiene test and questionnaire survey were carried out from targeting. 1. The young adult group and older adult group had the same quality in oral health level score and living habit. 2. The oral hygiene status in young adult and older adult group was same in 7 items(58.33%) out of 12 items. 3. Oral health level score in self-assessed of young adult group could be explained with 34% by 3 variables. Older adult group could be explained with 26% by 2 variables. 4. In young adult, the fitness of path model was very good with 0.96 in CFI, 0.94 in TLI, and 0.00 in RMSEA. In older adults, the fitness of path model was very good with 1.00 in CFI, 1.15 in TLI, and 0.00 in RMSEA. This might imply if TMJ disorder level and number of infection is neglected in young aldults, mastication function will be significantly effected in older adults. Thus, development and management of health education program is needed based on self-assessment oral health level by young adults group and older adults group.

• Korean Journal of Environmental Agriculture
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• v.32 no.4
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• pp.332-337
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• 2013

BACKGROUND: Newly reclaimed land has poor soil environment for crop growth since it is high in salt concentration but low in organic content compared with ordinary soil. It is known that whole-crop-barley can grow better in the soil of relatively high salt concentration than other crops but, the growth is poor at the concentration if higher than certain amount and it is a difficulty to secure productivity. Hence, the level of soil salt concentration suitable for the production of bulky feed in newly reclaimed land has been investigated. METHODS AND RESULTS: At Saemanguem reclaimed land, the land for the soil salt concentration electrical conductivity (EC) 0.8, 3.1, 6.5, 11.0 dS/m was selected; and chemical fertilizer $N-P_2O_5-K_2O$ (150-100-100kg/ha) was tested; and forage barley 220kg/ha were sown. The soil salt concentration during the cultivation period decreased in the order of harvest season>earing season>sowing season>wintering season, and the salt concentration in harvest season is 1.4-4.2 times higher than that of the sowing season. The higher the salt concentration, the poorer the over ground growth due to poor rooting; especially at EC 11.0 ds/m there was emergence but, it blighted after wintering. The Yield from the soil salt concentration 3.1dS/m and 6.5 dS/m was 68% and 35% from that of the soil salt concentration 0.8 dS/m (8.8 MT/ha) respectively. The proline content in early life stage was more than that of the harvest season, and it increased with salt concentration. The higher salt concentration, the more $Na_2O$ and MgO content in harvest season; but the higher the salt concentration, the less the content of N, $P_2O_5$, $K_2O$ and CaO. CONCLUSION(S): When the soil salt concentration becomes higher than 3.1 dS/m, the yield becomes poor because there is serious growth inhibition of forage barley both in root part and above aerial part that results in unbalanced absorption of nutrients. Therefore, it is recommended that the salt concentration should be lowered below 3.1 dS/m by underground drainage facilities or irrigating water for the stable production of whole-crop-barley.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.22 no.4
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• pp.151-171
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• 2017

Most of oceanic current maps in the secondary school science and earth science textbooks have been made on the base of extensive in-situ measurements conducted by Japanese oceanographers during 1930s. According to up-to-date scientific knowledge on the currents in the Yellow Sea and the East China Sea (YES), such maps have significant errors and are likely to cause misconceptions to students, thus new schematic map of ocean currents is needed. The currents in the YES change seasonally due to relatively shallow water depths, complex terrain, winds, and tides. These factors make it difficult to construct a unified ocean current map of the YES. Sixteen major items, such as the flow of the Kuroshio Current into the East China Sea and its northward path, the origin of the Tsushima Warm Current and its path into the Korea Strait, the path of Taiwan Warm Current, the Jeju Warm Current, the runoff pattern of the Yangtze River flow, the routes of the northward Yellow Sea Warm Current, the Chinese Coastal Current, and the West Korea Coastal Current off the west coast of the Korean Peninsula, were selected to produce the schematic current map. Review of previous scientific researches, in-depth discussions through academic conferences, expert discussions, and consultations for three years since 2014 enabled us to produce the final ocean current maps for the YES after many revisions. Considering the complexity of the ocean currents, we made seven ocean current maps: two representative current patterns in summer and winter, seasonal current maps for upper layer and lower layer in summer and winter, and one representative surface current map. It is expected that the representative maps of the YES, connected to the current maps of the East Sea and the Northwest Pacific Ocean, would be widely utilized for diverse purposes in the secondary-school textbooks as well as high-level educational purposes and even for scientific scholarly experts.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.1
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• pp.75-80
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• 1999

A field experiment was carried out to determine the optimum application level of dicamba herbicide for efficient control of Abutilon avicennae in silage corn field. Five treatments of application levels (0 ; control, $0.75{\ell},\;1.0{\ell},\;1.25{\ell}\;and\;1.5{\ell}$) were arranged at National Livestock Research Institute, RDA, Suwon in 1995 and 1996. The hybrid silage corn was P 3352 and dicamba herbicide was applied at 5~6 leaf stage of corn. The growth of corn was poor in control plot, and the days for tasseling and silking were delayed 2~3 days when compared with the plots of herbicide application. The control efficiency of Abutilon avicennae was excellent as 94.7~98.1% in the plots of dicamba application. A slight injury of herbicide was observed at early stage of corn when applied at $1.0{\ell},\;1.25{\ell}\;and\;1.5{\ell}$ of dicamba per ha. Forage dry matter(DM) yield, length and weight of ear in the plots of dicamba treatments were significantly higher than those of control. The DM yield of control(12,070kg/ha) was only 64.2~66.9% of dicamba treatment plot(18,050~18,795kg/ha). However, there was no yield difference among dicamba application level. The percentage of ear to total DM yield was ranged from 53.4 to 56.8%. The nutritive value(crude protein, ADF, NDF, digestibility and TDN) was very similar among all treatments. From the above results, it is recommended that optimum application level of dicamba herbicide was $0.75{\sim}1.0{\ell}/ha$ for efficient control of Abutilon avicennae and for silage corn production without herbicide injury.

• Journal of Korean Society of Transportation
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• v.19 no.4
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• pp.35-47
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• 2001

Traffic represents one of the largest sources of primary air pollutants in urban area. As a consequence. numerous abatement strategies are being pursued to decrease the ambient concentration of pollutants. A characteristic of most of the these strategies is a requirement for accurate data on both the quantity and spatial distribution of emissions to air in the form of an atmospheric emission inventory database. In the case of traffic pollution, such an inventory must be compiled using activity statistics and emission factors for vehicle types. The majority of inventories are compiled using passive data from either surveys or transportation models and by their very nature tend to be out-of-date by the time they are compiled. The study of current trends are towards integrating urban traffic control systems and assessments of the environmental effects of motor vehicles. In this study, a methodology of motor vehicle emission calculation by using real-time traffic data was studied. A methodology for estimating emissions of CO at a test area in Seoul. Traffic data, which are required on a street-by-street basis, is obtained from induction loops of traffic control system. It was calculated speed-related mass of CO emission from traffic tail pipe of data from traffic system, and parameters are considered, volume, composition, average velocity, link length. And, the result was compared with that of a method of emission calculation by VKT(Vehicle Kilometer Travelled) of vehicles of category.

• Journal of Animal Science and Technology
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• v.52 no.1
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• pp.1-8
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• 2010

This study is conducted to use the real-time ultrasound measurement data of Hanwoo as basic data being available to improvement. We used the ultrasound measurement data of 1,125 heads of performance tested cattle and the carcass data after castrating at about 12 months of age, fattened to 30 months, and then sold. For 921 heads of progeny tested cattle, we used test data and slaughter data. Heritabilities of ultrasound data for longissimus muscle area and backfat thickness measured at 12 months of age were estimated as 0.57 and- 0.41, respectively, and at 24 months of age, it was 0.57 and- 0.60, respectively, with high heritability. However, in estimation value of heritability containing ultrasound measurement for percent intramuscular fat, it showed low and medium heritability as 0.14 at 12 months of age and 0.22 at 24 months of age for each. The longissimus muscle area, backfat thickness, and percent intramuscular fat of ultrasound measure traits and longissimus muscle area, backfat thickness, marbling score of carcass traits genetic correlation of at 12 months of age were estimated as 0.616, 0.544, 0.501, respectively and at 24 months of age, it showed high genetic correlation as 0.894, 0.937, 0.263, respectively. As a result of ranking correlation between selection index by using weight, carcass traits at 12 months of age and selection index based on ultrasound measurement data which has high genetic correlation, in data of ultrasound measurement at 12 months of age, it showed high ranking correlation as that selection index of young bull was 0.140 and that of proven bull was 0.843.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.3
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• pp.499-506
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• 1999

The odontoma is relatively a common benign odontogenic tumor and caused by overgrowth of odontogenic tissues. The recent classification by World Health Organization divides odontoma into 2 groups such as compound odontoma and complex odontoma. Compound odontoma comprises dental tissues, resembling the morphology of a tooth and has predilection for the anterior maxilla. In contrast, complex odontoma has unorganized mass, not resembling the normal tooth and has predilection for the posterior mandible. The etiology of odontoma is unknown and almost asymptomatic. So, it usually is found in routine radiographic examination, and most common presenting symptom is impacted or unerupted permanent teeth and retained primary teeth. It can occurs almost anywhere in jaws. It is desirable that odontoma should be removed by surgical enucleation including follicle and surrounding soft tissues. Considering the age and behavioral cooperation of patient, the development of permanent dentition, the location of odontoma in jaw, the need for the concomitant operative dentistry, operation is performed in outpatient department with/without sedation or under general anesthesia with endotracheal intubation. In this case report, 2 patients with compound odontoma were treated by surgical enucleation including follicle and surrounding soft tissues. One patient, about 5 years old, was treated under general anesthesia and concomitant operative dentistry was performed. The other patient, about 11 years old, was treated under local anesthesia in outpatient department. In 2 cases, after 4 months, surgical defects were filled with new bone and normalization of eruption path of impacted permanent teeth was observed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.9
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• pp.1501-1514
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• 2004

The purpose of this study was to evaluate the health condition and nutritional status in female university students in Masan. The 285 subjects aged 20.1 years (18~26 years) were assessed with a set of questionnaire composed of general information, food, smoking, drinking and exercise habits, anthropometric measurements, blood pressure measurements, 24-hour recall and food frequency questionnaire. The rates of smoking and alcohol drinking habits were 1.8% and 82.5%, respectively. All the subjects had the experience of passive smoking. The 11% of the students exercised regularly and 11.6% ate meal regularly. The average height and weight of subjects were 161.0 ㎝ and 53.9 ㎏, respectively and the BMI was calculated as 20.8${\pm}$2.6 ㎏/$m^2$:The 13.3% of subjects were underweight, while 6.7% of them were overweight. The mean value for body fat was 26.4% and subscapular and tricep skinfolds thickness were 14.2 ㎜ and 16.9 ㎜, and waist-hip ratio was 0.72. The systolic/diastolic blood pressure of the subjects was 115.9 ㎜Hg/70.9 ㎜Hg. Except protein, phosphorous, vitamin E, B_6 and C, the average intakes of energy and nutrients were below the Korea recom-mended dietary allowance (RDA). Especially, intakes of calcium, iron and zinc were the lowest, as <70% of RDA. The proportion of energy derived from carbohydrates : protein : fat was 58.0 : 15.8 : 26.2. The 10 frequently consumed food were ssalbap (47.2/mon), kimchi (35.6/mon), onion (16.8/mon), japgokbap (15.1/mon), sesame oil (14.1/mon), carbonated drink (13.3/mon), grapes (12.7/mon), ice cream (12.4/mon), milk (11.9/mon) and water-melon (10.6/mon). Results of this study could be useful for planning nutrition education programs for female university students in this area to improve their dietary habit and health status.

• Journal of Korean Society of Forest Science
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• v.53 no.1
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• pp.56-61
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• 1981

Total 183 private forest owners in Chungnam-Do were surveyed in order to analyse the attitudes toward cooperative forest management and to find out the relationship of the attitudes with such socio-economic variables as owners' socio-economic status(SES), age and educational level. Major findings of the study are summarized as follows:- 1. Only 17.5 percent of the owners regards the cooperative management as a desirable alternative for the management of private forests. Significant difference of their attitudes is recognized only among the classes of the educational level. 2. About one-third of the owners wishes to participate to a cooperative, if established. The owners' intention of participating is positively related to the degree of S.E.S. and educational level, but negatively associated with that of age variable, and the differences among the classes of all variables are significant at the 0.01 or 0.05 levels. 3. More than half of the owners desires to have limited cooperatives, in which the members themselves manage their forest land with some management aspects being handled by the cooperative such as procurement of seedlings, protection measures, and marketing. The difference of responses among the classes of educational level is significant at the 0.01 level. 4. The owners, who agree with the idea of voluntary membership in the cooperative, are about 45 percent of the total. Significant difference is found only among the classes of the S.E.S. variable. 5. Nearly 60 percent of the owners wants to have self-help cooperative organizations. Significant difference of responses is recognized only among the classes of the age variable.