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Seasonal Prevalence of the Vector Mosquitoes of Japanese Encephalitis Virus in Kyungpook Province, Korea (경북지역에서의 일본뇌염 매개모기에 출현 소장)

  • 주종윤;화전의인
    • Parasites, Hosts and Diseases
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    • v.23 no.1
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    • pp.139-150
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    • 1985
  • In order to determine the seasonal prevalence and population density of vector mosquitoes in Kyungpook Province, a survey based on average numbers of female mosquito per trap-night, were carried out during the period from May to November in 1984. Among the 34, 571 mosquitoes collected in Kyungsan county in animal shelters and human dwellings by light traps, approximately 45.0 per cent were Culex tritaeniorhynchus, 34.0 per cent Culex pipiens pallens, and 19.0 per cent Anopheles sinensis. By comparison, distribution of mosquito species in Ankang town, in which Japanese encephalitis had been reported in the past, were quite different and A. sinensis was the most abundant species, being constituted in 75.8 per cent, followed by C. tritaeniorhynchus(23.2 per cent), and C. pipiens pallens(O.6 per cent). In the general pattern of seasonal prevalence, C. tritaeniorhynchus first appeared in mid-June, and trapped in large numbers during the periods from mid-August to early September, showing a simple sharply pointed one-peaked curve, while C. pipiens pallens was found to be active through almost the entire season showing irregular curves with several peaks. The trend of seasonal distribution of A. sinensis was similar to that of C. tritaeniorhynchus, but the earliest dates of appearance and disappearance differed from that of C. tritaeniorhynchus. The results of hourly catches of mosquitoes by human baited traps have clearly shown the differences in the biting rhythm among the vector mosquitoes of this Province, such as the facts that C. tritaeniorhynchus and A. sinensis are rather constantly active all through a night with more or less inconspicuous peaks twice a night, while C. pipiens pallens exhibits an irregular curve, and the numbers of A. vexans nipponii, C. vagans and Armigeres subalbatus are very small and are not sufficient for estimating the biting rhythm. Four genera and fourteen species of larval mosquitoes collected from eighteen kinds of habitats which classified according to the categories followed by Bates (1949). The main breeding sites contributing to peak C. tritaeniorhynchus adult densities in this surveyed areas were evidently ricefields, ground pools, puddles and swamps and marshes, etc. Summarizing the results, this study indicated that the highest population density of C. tritaeniorhynchus was encountered in late August and early September, showing a simple sharply pointed one-peaked curve.

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Andic Properties of Major Soils in Cheju Island -III. Conditions for Formation of Allophane (제주도(濟州島) 대표토양(代表土壤)의 Andic 특성(特性)에 관한 연구(硏究) -III. Allophane 생성조건(生成條件))

  • Song, Kwan-Cheol;Yoo, Sun-Ho
    • Korean Journal of Soil Science and Fertilizer
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    • v.27 no.3
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    • pp.149-157
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    • 1994
  • The conditions for formation of allophane in volcanic ash soils in Cheju Island were investigated. Soils of toposequence distributed along the sourthern slope of Mt. Halla, and the major soil groups such as dark brown soils, very dark brown soils, black soils, and brown forest soils were colleted and analyzed for Al, Fe and Si extracted with solutions of pyrophosphate and oxalate. Mean annual temperature decreased $0.8^{\circ}C$ and mean annual precipitation increased 110mm with increase elevation of 100m. Organic carbon content increased and soil pH decreased with elevation, and the formation of allophane in soils formed a climosequence. Dark brown soils widely distributed in the northern and western coastal areas, where the mean annual precipitation ranged 1,240~1,420mm and the evaporation ranged 1,290~1,320mm, contained only small amounts of allophane and Al-humus complexes. For other soils, organic carbon content, pyrophosphate extractable Al, and $Al_p/Al_o$ were inversely correlated with $pH(CaCl_2)$. Allophane content showed close relationships wlth $pH(CaCl_2)$, and inverse relationships with organic carbon content and $Al_p/Al_o$.

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A Study on Detailed Bathymetry and Geophysical Characteristics of the Summit of the Dokdo Volcano (독도 화산체 정상부해역의 정밀해저지형 및 지구물리학적 특성 연구)

  • Kim, Chang Hwan;Park, Chan Hong;Lee, Myoung Hoon;Choi, Soon Young;Jou, Hyeong Tae
    • Economic and Environmental Geology
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    • v.45 no.6
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    • pp.685-695
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    • 2012
  • We studied the detailed bathymetry and the geophysical characteristics of the summit of the Dokdo volcano using mutibeam echosounding and geophysical survey data. The bathymetry around the main east and west islets of the Dokdo volcano shows very shallow within about 10 m water depth. From near islets to about 30 m b.s.l., the shallow water area has very steep slope and many irregular sunken rocks. The area from about 30 m to about 80 m b.s.l. shows gentle rises and falls, and less steep slope. The area from 80 m b.s.l. has gradually flat undulation and smooth slope seabaed and is extended to offshore. The main islets of the Dokdo volcano and the rocky sea bottom elongated from the islets might be the residual part of the eroded and collapsed main crater of the Dokdo volcano. The bathymetry and the seafloor image(from backscattering) data show small craters, assumed to be formed by the eruption of later volcanism. The seafloor images propose that, except some areas with shallow sand sedimentary deposits, there are typical rocky bottom such as rocky protrusions and lack of sediments in the main morphology of the survey area. The stepped slopes of the seabed are deduced to be submarine terraces. The several prominent submarine terraces are found at the summit of the Dokdo volcano, suggesting repetition of sea level changes(transgressions and regressions) in the Quaternary. The results of the magnetic anomaly and the analytic signal have a good coherence with other geophysical consequences regarding to the location of the residual crater.

Sorption Efficiency of the Bamboo Charcoal to Remove the Cesium in the Contaminated Water System (오염수계 내 세슘 제거를 위한 대나무 활성탄의 흡착효율 규명)

  • Ahn, Joungpil;Lee, Minhee
    • Economic and Environmental Geology
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    • v.51 no.2
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    • pp.87-97
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    • 2018
  • The cesium (Cs) removal from the contaminated water system has been considered to be difficult because the cesium likes to exist as soluble phases such as ion and complexes than the solid in water system. Many researches have focused on developing the breakthrough adsorbent to increase the cesium removal efficiency in water. In this study, the laboratory scale experiments were performed to investigate the feasibility of the adsorption process using the bamboo charcoal for the Cs contaminated water system. The Cs removal efficiency of the bamboo charcoal were measured and the optimal adsorption conditions were determined by the adsorption batch experiments. Total 5 types of commercialized bamboo charcoals in Korea were used to identify their surface properties from SEM-EDS and XRD analyses and 3 types of bamboo charcoals having large specific surface areas were used for the adsorption batch experiment. The batch experiments to calculate the Cs removal efficiency were performed at conditions of various Cs concentration (0.01 - 10 mg/L), pH (3 - 11), temperature ($5-30^{\circ}C$), and adsorption time (10 - 120 min.). Experimental results were fitted to the Langmuir adsorption isotherm curve and their adsorption constants were determined to understand the adsorption properties of bamboo charcoal for Cs contaminated water system. From results of SEM-EDS analyses, the surfaces of bamboo charcoal particles were composed of typical fiber structures having various pores and dense lamella structures in supporting major adsorption spaces for Cs. From results of adsorption batch experiments, the Cs-133 removal efficiency of C type bamboo charcoal was the highest among those of 3 bamboo charcoal types and it was higher than 75 % (maximum of 82 %) even when the initial Cs concentration in water was lower than 1.0 mg/L, suggesting that the adsorption process using the bamboo charcoal has a great potential to remove Cs from the genuine Cs contaminated water, of which Cs concentration is low (< 1.0 mg/L) in general. The high Cs removal efficiency of bamboo charcoal was maintained in a relatively wide range of temperatures and pHs, supporting that the usage of the bamboo charcoal is feasible for various types of water. Experimental results were similar to the Langmuir adsorption model and the maximum amount of Cs adsorption (qm:mg/g) was 63.4 mg/g, which was higher than those of commercialized adsorbents used in previous studies. The surface coverage (${\theta}$) of bamboo charcoal was also maintained in low when the Cs concentration in water was < 1.0 mg/L, investigating that the Cs contaminated water can be remediated up with a small amount of bamboo charcoal.

Material Characteristics and Provenance Interpretation for Chloritic Beads from the Boseong Geoseokri and Haenam Buntori Sites, Korea (보성 거석리 및 해남 분토리 유적 출토 녹니석제 구슬의 재질특성과 원산지 해석)

  • Kim, Ji-Young;Lee, Chan-Hee;Kim, Jin-Young
    • Journal of Conservation Science
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    • v.23
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    • pp.25-37
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    • 2008
  • This study focuses on identification of mineralogical and geochemical characteristics and interpretation of raw material sources for prehistoric chlorite beads excavated from Geoseokri site in Boseong and Buntori site in Haenam, Korea. These prehistoric beads consist of three grayish blue ring-shaped beads, one dark green tubular bead and one greenish black tubular bead that show acicular-columnar and fibrous microtexture. The beads are composed of $SiO_2$, $Al_2O_3$, MgO and FeO as majors and a trace amount of $K_2O$, CaO and Na_2O$. Mineral species is mostly chlorite with a small amount of quartz and feldspar. Quantitative analysis indicates that the grayish blue ring-shaped beads and the dark green tubular bead belong to clinochlore and the greenish black tubular bead does to the boundary between clinochlore and sheridantie. Chlorite is a hydrous phyllosilicate mineral and it shows various microtexture of acicular, sheeted, earthy, granular andfibrous shapes. As its hardness is 2, chlorite is easily engraved due to its softness. It has aesthetic worthy as it shows green, black and greenish gray colors and pearly to greasy luster as well. These factors would lead to the extensive use of chloritic beads as ornaments from prehistoric times. Though the mineral sources of the chlorite beads can be found in central western region of Chungnam and Iwon of Hamnam, those areas are too distant from the two relic sites. Instead, chlorite ores commonly occur as altered products in wall rock alteration zone of every hydrothermal deposit. Therefore, it is probable that raw materials of chlorite were supplied from neighboring hydrothermal environment rather than far deposits. The result needs further study to verify raw material provenance interpretation, supply, manufacture and distribution on the basis of archaeological points of view.

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A Study on Process Optimization for CSOs Application of Horizontal Flow Filtration Technology (수평흐름식 여과기술의 CSOs 적용을 위한 공정 최적화 연구)

  • Kim, Jae-Hak;Yang, Jeong-Ha;Lee, Young-Shin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.2
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    • pp.56-63
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    • 2018
  • The management of Combined Sewer Overflows(CSOs) and Separated Sewer Overflows(SSOs) discharge directly to the effluent system in an untreated state, which occurs when the facility capacity is exceeded due to heavy rain, has become an important issue in recent years as the heavy rain becomes a regular phenomenon. Despite the continuous development of filtration technology, targeting densely populated urban areas, CSOs are rarely applied. Therefore, this study was carried out to optimize the process to apply CSOs in a pilot-scale horizontal flow filtration system with a rope-type synthetic fiber. The research was carried out in two steps: a preliminary study using artificial samples and a field study using sewage. In the preliminary study using an artificial sample, head loss of the filter media itself was analyzed to be approximately 1.1cm, and the head loss was increased by approximately 0.1cm as the linear velocity was increased by 10m/hr. In addition, the SS removal efficiency was stable at 81.4%, the filtration duration was maintained for more than 6 hours, and the average recovery rate of 98% was obtained by air backwashing only. In the on-site evaluation using sewage, the filtration duration was approximately 2 hours and the average removal efficiency of 83.9% was obtained when belt screen (over 450 mesh) was applied as a pre-treatment process to prevent the premature clogging of filter media. To apply the filtration process to CSOs and SSOs, it was concluded that the combination with the pre-treatment process was important to reinforce the hydraulic dimension for the stable maintain of operation period, rather than efficiency. Compared to the dry season, the quality of incoming sewage was lower in the rainy season, which was attributed to the characteristics of the drainage area with higher sanitary sewerage. In addition, the difference in removal efficiency according to the influent quality of the wet season and dry season was small.

The Trend of Regional Geography in Germany in the 1920s and 1930s ($1920{\sim}1930$년대(年代) 독일(獨逸) 지지학(地誌學)의 연구(硏究) 동향(動向))

  • Kim, Jae-Wan
    • Journal of the Korean association of regional geographers
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    • v.6 no.1
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    • pp.69-89
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    • 2000
  • The regional geography had been at the height of prosperity in the first half of the twentieth century since Alexander von Humboldt and Carl Ritter. The geography remained stationary in the late 19th century had greatly developed around the regional geography in European countries since the early 20th century. Particularly, A. Hettner and O. $Schl{\ddot{u}}ter$ in Germany, Vidal de la Blache in France and A. J. Herbertson in Britain developed their own methods of regional studies and produced many results of empirical studies ; accordingly the regional geography had been at the height of prosperity in the 1920s and 1930s. This paper aims to study the regional concepts and the methods of regional studies of Germany geographers in the 1920s and 1930s. This study is useful to understand the current methods of classifications of regions and descripitive systems of regions. The noteworthy results of studies are summarized as follows : First, The regional geography of Germany had been developed by Hettner who regarded the geography as the chorological science of the earth's surface, $Schl{\ddot{u}}ter$ who did the geography as the study of cultural landscape and Penck's students, the morphologists of landscape (Landschaftsmorphologie). Hettner defined the geography as the chorological science, maintained that the earth's surface was classify according to its localized difference -continents, lands, districts and localities(Erdteile, $L{\ddot{a}}nder$, Landschaften und Ortlichkeiten) and emphasized on the total character of areas. He tried to classify downward from continents to localities based on the sizes of regions. He also gave the logic of causal relation to schematic approach(Das $L{\ddot{a}}nderkundliche$ Schema) and further developed it. $Schl{\ddot{u}}ter$ argued that The process of change on the landscape through time must be studied. And Passarge and Penck's pupils, morphologists of landscape, tried to classify the landscape synthetically. Thereafter, De Geer and $Gran{\ddot{o}}$ employed the creative methods of regional classification which used signs and simbols. Second, The regional geography of Germany differed from that of France on the next points ; 1. The former was analytic, but the latter was synthetic. 2. The former placed great emphasis on physical elements, terrain and climate etc., but the latter did great emphasis on both physical and human elements. 3. The former gave priority to the studies of large scale regions, but the latter did priority to the studies of small scale regions. In 1920s and 1930s the regional study of Germany geographers exerted direct influence on the development of geography of Japan. Especially, Tanaka Keiji, Japanese typical regional geographer, tried to classify Japan synthetically on the bases of terrain, climate, vegetation and human elements under the influence of European geographers. He exerted great influence on both Japanese and Korean geographers at that time.

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Radiosurgery with Linac Based Photon Knife in Cerebral Arteriovenous Malformation (선형가속기를 이용한 Photon Knife 방사선수술에 의한 뇌동정맥기형의 치료)

  • Kim, Jin-Hee;Choi, Tae-Jin
    • Radiation Oncology Journal
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    • v.21 no.1
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    • pp.1-9
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    • 2003
  • Purpose : The purpose of this study was to analyze the effect of a Linear accelerator based Photon Knife Radiosurgery System developed by the staff of Keimyung University Dongsan Medical Center for the treatment of cerebral arterlovenous malformation Material and Methods : Between December 1993 and October 2000, 30 patients with cerebral arteriovenous malformation (AVM) were treated with the Linac based Photon knife Radlosurgery System In the Department of Therapeutlc Radiology at Keimyung University Dongsan Medical Center. The median age was 34, ranging from 7 to 63 years, with a 2 : 1 male to female ratio. The locations of the AVM nidi were the frontal lobe (motor cortex), parletal lobe, and the thalamus, In that order. The diameters of the AVM nidi ranged 1.2 to 5.5 cm with a mean on 2.9 cm, and target volumes of between 0.5 and 20.5 cc, with a mean of 5.8 cc. The majority of patients received radiation doses of between 1,500 and 2,500 cGy, w14h a mean of 2,000 cGy, at 80% the isodose line. Twenty-five patients were treated with one isocenter, 4 with two, and 1 with four. The follow-up radiological evaluations were peformed with cranial computed tomogram (CT) or MRI between 6 month and one year interval, and if the AVM nidus had completely disappeared in the CT or MRI, we confirmed thls was a complete obliteration, with a cerebral or magnetic resonance angiogram (MRA). The median iollow-up period was 39 months with a range of 10 to 103 months. Results : Twenty patients were radloiogicaiiy followed up ior over 20 months, with complete obliteration observed in 14 (70%). According to the maximal diameter, all four of the small AVM (<2 cm) completely obliterated, 8 of the 10 patients with a medium AVW (2~3 cm) showed a complete obliteration, and two showed partial obliteration. Among the patients with a large AVM (>3 cm), only one showed complete obliteration, and S showed partial obliteration, but 3 oT these underwent further radiosurgery 3 years later. One who followed up for 20 months fellowing further radiosurgery eventually showed complete obliteration. Ten patients with seizure symptoms had no recurrent seizure due to radiosurgery and medication. One of the eleven patients who suffered intracranlal bleeding developed further bleeding at 9 and 51 months fellowing the radiosurgery although complete obliteration was eventually observed and the patient was managed in hospital then recovered. No patient suffered severe complications fellowing the radiosurgery. Conclusion : The radiosurgery with Linac-based Photon knife radiosurgery system, developed by the staff at our hospital, is a safe and effective treatment for AVM patients having diameters or volumes of less than 3 cm or 10 cm$^{3}$, respectively, located In Inoperable areas or who refused neurosurgery. We suggest that staged AVM radiosurgery may initially be considered, if the AVM target volume is above 10 cm$^{3}$

Histopathologic Observation of the Aborted Fetus from Pregnant Dairy Cows Naturally Infected with Neospora caninum (Neospora caninum에 자연 감염된 임신우로부터 유산된 태아의 병리조직학적 관찰)

  • Son, Jeong-Hoon;Cho, Sung-Whan
    • Journal of Life Science
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    • v.20 no.10
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    • pp.1556-1562
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    • 2010
  • This study examined the histopathologic and electron microscopic findings of aborted fetuses from pregnant dairy cows naturally infected with Neospora caninum (N. caninum) at four farms in Gongju city and Yeonki gun of Choongnam province. Systemic subcutaneous edema was observed in the aborted fetuses. The necropsy revealed considerable serosanguinous fluid in the body cavity of the aborted fetuses. Light microscopy showed the infiltration of many inflammatory cells consisting of macrophages, lymphocytes and mononuclear cells, accompanied by congestion, hemorrhage and necrosis of myocardiac cells and hepatocytes in the liver and heart of the aborted fetuses. In the liver, clusters of tachyzoites were formed in the cytoplasm of hepatocytes and the interstitial tissue. In the brain, many tissue cysts of various sizes were observed in the nerve cells and their adjacent areas. Tissue cysts had a round shape and contained a large amount of bradyzoite. In addition, there was diffuse gliosis accompanied by congestion and hemorrhage and focal necrosis in the brain. Infiltration of microglial cells were observed at the periphery of the focal necrosis and perivascular area in the brain. Electron microscopy showed that the tissue cyst wall had a thickness of approximately 1 ${\mu}m$ with an irregular shape. On the interior side, more than 100 bradyzoites with lengths of 2-5 ${\mu}m$ and widths of 1-2 ${\mu}m$ were observed. The nucleus of in the bradyzoites was located approximately 1-1.5 ${\mu}m$ anterior to the posterior tip of the zoite. In the cytoplasm between the nucleus and the posterior tip, there were many amylopectin granules, electron-dense small-sized and electron-thin large-sized round granules, homogeneously electron-dense rhoptries and micronemes oriented perpendicularly to the zoite pellicle. To summarize, tissue cysts were identified on electron microscopy from the aborted fetus from N. caninum seropositive pregnant cow by the ELISA. This led to the confirmed presence of N. caninum.

A study model standardization by he body types of Jugori of Hanbok for middle-aged women (중년 여성을 위한 한복 저고리의 체형별 원형 연구)

  • 진현선;권미정
    • Journal of the Korea Fashion and Costume Design Association
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    • v.5 no.1
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    • pp.13-24
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    • 2003
  • The purpose of this study is to design Jugori model compatible with the body types of the middle-aged women especially from 40 to 59 years old. The result is as follows: We decided five items as the necessary items for designing jugori model : the bust girth (the breast & shoulder width), the B.P length, the neck width, the armhole circumference, and Hwa-jang. The breast & shoulder width are the size that comes out if the bust is divided by the breast & shoulder width on the basis of the side line, and Hwa-jang is a length measured with arms stretched out to 0° direction. With each person's physical characteristics considered, the application of the size of each body types and body parts is as follows: 1. The breast & shoulder width (1/4 portion) : We decided B/4+2cm as a standard size and, we adjusted the extra room on the basis of the discrepancy between the breast width and the shoulder width to make it fit well to the each body type. For the breast width (1/2 portion), we bisected the difference between the breast width and the shoulder width of the bust, and moved Gut-sup to the center of the Sup and Sup-sun for An-sup. According to the body type, the movement of the Sup for the people with big breasts gets bigger because there should be a big difference between the breast width and the shoulder width for them, and for the people with small breasts the movement will be relatively smaller. For the shoulder width (1/2 portion), we curved the back center line after we shortened as much as the difference between the amount of the shoulder width/2+1cm and of B/4+2cm. The movement of back center line will be bigger for a person with leaned-backward body type. 2. The front & back length: We made the front length to B.P length+2.5cm to have Jugori cover the breast point fully around the bust line, which is a vogue nowadays. For an upright body type, we decided the back length as (AH/2.2)+5cm. And for a bent-forward and a leaned-backward body type, we adjusted the calculation formulae differently taking the physical characteristics into account. We decided the back length (A) as (A.H/2.2)+5cm, and the front length (B) as the back length+5cm. So, (A+B) is the sum of the front length and the back length. Going back to the original formula, the front length is B.P+2.5cm. So, we can decide the back length if we subtract B.P+2.5cm from the sum of the front length and the back length. To make well-fit Jugoris, the front & back length are areas that we should pay attention to if we take each person's physical characteristics into consideration. 3. Go-dae (1/2 portion) : We decided Go-dae as the neck width/2+0.5cm. For an upright body type, because the base line which went down vertically from the tragion was straight, we generally decided Go-dae Dalim line as 1.0cm. But we decided Go-dae Dalim line down to 1.5cm for bent-forward type and up to 0.2cm for leaned-backward type because the upper half of the body of them was bent forward or leaned backward from the base line. 4. The armhole : We decided the armhole circumference as A.H/2+2cm with the whole extra room of 4cm. 5. The side line length : We can calculate the side line length to (the back length-the armhole)/2, and, in terms of the trend, 2.5cm will be appropriate.

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