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Giant Coronary Artery Aneurysm Presenting as a Calcified Mediastinal Mass a, Coronary Artery Fistula - A case report - (종격동 종양으로 오인된 거대관상동맥류와 관상동맥루 - 치험 1례 -)

  • Yoon, You-Sang;Lee, Cheol-Joo;Choi, Ho;Kang, Jun-Kyu;Choi, Jin-Wook;Kim, Hyung-Tae
    • Journal of Chest Surgery
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    • v.34 no.10
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    • pp.787-791
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    • 2001
  • Coronary artery aneurysm is a rare disorder. It is defined as abnormal dilatation of coronary artery with diameter exceeding 1.5 times the adjacent normal segments. The incidence of coronary aneurysm is 2.6% in Caucasians and 0.25% in Asians. Over half of the former were associated with atherosclerotic coronary artery disease. However, 70 percents of the latter were nonobstructive coronary artery aneurysms. Coronary artery fistula is a rare disorder. It has been identified in only 0.2% of routine cardiac angiographic studies conducted over a 10-year period. The clinical spectrums are various, asymtomatic, asymptomatic murmur, dyspnea on exertion, fatigue, and congestive heart failure. The right coronary artery (56%) and left coronary artery(36%) are mainly involved in the origin site of congenital coronary artery fistula. The draining site of fistula are right ventricle(39%), right atrium(33%), and pulmonary artery(20%) and so on. This 54 years-old woman had intermittent chest tightness and an abnormal mediastinal shadow on chest roentgenogram and chest C-T examination, which was diagnosed as a mediastinal mass such as teratoma. We performed the operation under left anterolateral thoracotomy for mass excision. However, we knew the mass had the pulsating arterial blood flow through a fine needle puncture of the mass and that it was attached to the left ventricle. We believed the excision of mass on beating heart would be very dangerous. Therefore, we closed the wound without excising the mass. After several days, we performed an echocardiography and coronary angiography, We knew it was cardiac tumor. Incidentally, the patient had a tortuous coronary fistula from the right coronary artery to pulmonary trunk. Using cardiopulmonary bypass with moderate systemic hypothermia, the mass was resected and the fistula was clipped with surgical clips. Pathology of the specimen was a giant coronary arterial aneurysm.

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Effect of the Elevated Carbon Dioxide on the Growth and Physiological Responses of Peach 'Mihong' (CO2 상승처리가 복숭아 '미홍'의 수체생육 및 생리반응에 미치는 영향)

  • Lee, Seul Ki;Cho, Jung Gun;Jeong, Jae Hoon;Ryu, Suhyun;Han, Jeom Hwa;Do, Gyung-Ran
    • Journal of Bio-Environment Control
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    • v.30 no.4
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    • pp.312-319
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    • 2021
  • This study was conducted to investigate the effect of elevated carbon dioxide on the growth and physiological responses of peach 'Mihong' (Prunus persica). We simulated three different carbon dioxide conditions based on climate change scenarios RCP 8.5 in the sunlight phytotron rooms from April 22 to July 6, 2020; 400 µmol·mol-1(present condition), 700 µmol·mol-1 treatment(expecting carbon dioxide concentrations in mid-21st century), 940 µmol·mol-1 treatment (expecting carbon dioxide concentrations in late 21st century). The average of maximum photosynthesis rate at 700 µmol·mol-1(16.06 µmol·CO2·m-2·s-1) was higher than those at 400 µmol·mol-1(14.45 µmol·CO2·m-2·s-1) and 940 µmol·mol-1(15.96 µmol·CO2·m-2·s-1) from May 22 to July 2. However, stomatal conductances at 700 µmol·mol-1 and 940 µmol·mol-1 were lower than those at the control. Also, the carbon dioxide saturation point in all treatments was reduced from 1,200 µmol·mol-1 in the early stage of growth to 600-800 µmol·mol-1 in the late stage of growth. The stomatal densities were decreased as carbon dioxide increased. The shoot lengths were decreased while the carbon dioxide was increased, but the increase of trunk diameter and leaf areas, shoot numbers were not statistically different. The fruit weight at 700 µmol·mol-1(152.5 g) was higher than those at the control(141.8 g) and 940 µmol·mol-1(147.4 g). The soluble solids were higher at 700 µmol·mol-1, 940 µmol·mol-1 compared to the control. These results suggest that a carbon dioxide elevated to 700 µmol·mol-1 in the future may give a positive effect on the yield and fruit quality of peach 'Mihong' while a carbon dioxide elevated above 940 µmol·mol-1 may affect negatively such as early senescence and loss of fruit set.

Notes on the Status and Conservation of Callipogon Relictus Semenov in Korea (장수하늘소 현황 및 보전방안)

  • An, Seung Lak
    • Korean Journal of Heritage: History & Science
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    • v.43 no.1
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    • pp.260-279
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    • 2010
  • The analysis on bibliography and field investigation of Callipogon relictus Semenov, 1898 (Korean natural monument number 218) shows that the size varies from country to country, and Korean specimens, for which male is 85~120mm and female is 65~85mm, are found to be the largest. The average diameter and length of egg are 2.60mm and 6.72mm respectively. The larva has milky color and is about 100~150mm in length. The pupa is nearly 70~110mm. An adult generally appears from June to September in Korea in the broadleaf forest of lowland, whereas it appears from June to July in China. It is known that the pupa largely feed on the old tree trunk of Carpinus laxiflora (Siebold & Zucc.) blume in Korea, but no such data have been reported in China and Russia, showing differences in host plants. While the larva period is not exactly known in Korea, it is reported to be two years in China. It appears that the species inhabits in very limited regions of approximately between geographical latitude $37.5^{\circ}{\sim}47.8^{\circ}$ and longitude $126^{\circ}{\sim}140^{\circ}$ including Korea, China and Russia. To conserve the long-horned beetle in Korea, this research drew out following some conclusions through analyzing the references and field survey data. First, it need to perform precise survey on the natural environment of occurring and collected area or place including host plant kinds, temperate, humidity, latitude, longitude etc. Second, habitat region must be designated as a restricted development area, and it need to exclude or reduce the damage factors to prosper reproduction of the species. Third, it is necessary to keep loosing cautiously artificial breeding individuals in the reported sites, not disturbing scope of natural populations. Fourth, it needs to educate or publicize many people importance and value of this species through many methods.

Vegetative Propagation and Morphological Characteristics of Amelanchier spp. with High Value as Fruit Tree for Landscaping (정원용 유실수로서 가치가 높은 채진목속(Amelanchier spp.)의 형태적 특성 및 영양번식방법)

  • Kang, Ho Chul;Hwang, Dae Yul;Ha, Yoo Mi
    • Journal of the Korean Institute of Landscape Architecture
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    • v.46 no.6
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    • pp.111-119
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    • 2018
  • This study was carried out to investigate the growth characteristics and propagation methods of the Korean native Amelanchier asiatica, A. arborea, and A. alnifolia as fruit trees for gardens. Due to the lack of recent research on Amelanchier spp., their superficial classification is still unclear and the names are being used interchangeably. The results are obtained as follows : A. arborea and A. alnifolia were globular type multi-stemmed shrubs. A 20-year-old tree of A. asiatica was 7.8m in height, with a 5.2m crown width, with one trunk. As for the morphological characteristics, leaves of A. asiatica were oblong, with an acuminate of, 6.1cm and 3.6cm width, but A. arborea and A. alnifolia had acute obovate leaves. The leaf size of A. alnifolia was the largest among the three species. The flower size of A. asiatica was bigger than that of A. arborea and A. alnifolia. In addition, its petals and flower clusters were also the largest among the three species. The flowering of A. asiatica initiated on April 21 and then bloomed for a duration of 24 days in Osan, while that of A. arborea and A. alnifolia initiated flowering on April 12 and then bloomed for a duration of 22 days in the same location. The fruit of A. arborea and A. alnifolia were green on May 10~12, it changed into purplish red on May 24~26, and its matured on June 1~3. The duration of fruit persistence of A. arborea and A. alnifolia were 48~50 days. On the other hand, A. asiatica showed greenish fruit on May 20, it became red on September 4, and had fallen by October 3. The fruit size was the largest at 1.03cm of height and 1.12cm of diameter in the A. arborea, followed by the big berry of A. alnifolia and the smallest fruit in the native, A. asiatica. It was difficult to root due to the hardwood cutting of A. arborea at a 40% rate of rooting. In the softwood cutting, the rooting rate of A. arborea was increased by the treatment with concentrated IBA, especially at 5,000 and 7,000ppm. The optimum date for cutting was on June 27, when the rooting rate was more than 80%. The most effective method for rooting of A. arborea was rootone or 7,000 ppm IBA treatment on June 27 softwood cuttings, which showed a rooting rate of over 80%.

A Study on the Reasonable Measurement Point of Root Collar Diameter of Landscape Trees in Korea (한국 조경수목 근원직경 측정의 합리적 위치 설정에 대한 연구)

  • Han, Yong-Hee;Kim, Hwa-Jeong;Kim, Do-Gyun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.49 no.5
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    • pp.59-70
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    • 2021
  • This study was to investigate the measurement point of root collar diameter of landscape trees in Korea. It may contribute to avoiding disputes caused by the difference in measurement criteria of root collar diameter of landscape trees between tree growers and constructors. The difference between landscape trees' root collar diameter measurement point was 3.59cm from 6cm underground to the surface and 1.35cm from 0cm to 6cm above ground. The source root collar diameter measurement point difference was larger in the basement than in the ground. The standard deviation of the root collar diameter of the landscape tree was 0.64 from 6cm underground to the surface, and the difference in standard deviation from 0cm to 6cm above ground was 0.16. The difference by measurement point of the root collar diameter was larger in the basement than in the ground. It has been proposed to set the reasonable measurement point of the landscaping tree root collar diameter at the inflection point where the standard deviation of the tree trunk diameter is the smallest in line with the size change of the standard for each root collar diameter measurement point. By tree species, Cornus officinalis Siebold & Zucc. 18cm above the ground, Chionanthus retusus Lindl. & Paxton. 12cm above the ground, Zelkova serrata (Thunb.) Makino. 12cm above the ground, Celtis sinensis Pers. 12cm above the ground, Styrax japonicus Siebold & Zucc. 10 cm above the ground, Cornus officinalis Siebold & Zucc. 10cm above the ground, Acer palmatum Thunb. ex Murray. 6cm above the ground, Ilex rotunda Thunb. 6cm above the ground, Quercus myrsmaefolia Blume. 4cm above the ground, Lagerstroemia indica L. 2cm above the ground The above heights were shown as reasonable measurement points. The difference by landscape tree root collar diameter measurement site showed that the standard deviation was small throughout the tree species, and the reasonable average measurement point with a stable slope of the deviation was 12cm or more on average. It can be said that the reasonable measurement point of the root collar diameter of a landscape tree is set at an average of 12cm above the ground. However, recognizing 30cm, which is a familiar ruler(尺) in traditional practices, is quick, It was recommended to measure at the height of 30cm from the surface for a reasonable measurement point of the root collar diameter of a landscape tree, for the uniformity of measurement standards.

Research on an aristocratic officer's travels in the mid Chosun Korea by analysing Yu Hee-chun's diary (일기(日記)를 이용한 조선중기 양반관료의 여행 연구)

  • Jung, Chi-Young
    • Journal of Korean Historical Folklife
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    • no.26
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    • pp.71-106
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    • 2008
  • The objective of this research is to reconstruct an aristocratic officer's travels by analysing Yu, hee-chun's diary, Miamilgi. Yu had kept his diary for eighty three months, from October 1567 to May 1577, and there were twenty six times of travel logs which are analysed in this research. As a result of the analysis, his travels can be divided into official travels and private travels. Sixteen times of official travels were comprised of inspection tours for parishes as a superintendent of Jeonra province, trips to supervise maintenance works of royal tombs and to worship the tombs, to carry out the sanjae (rituals in the mountains) as a second minister of the ministry of rites. It was difficult for him to have private travels as he continually served as a royal officer. He had got only 10 times of private travels during the eighty three months for maintaining the ancestor's tomb and worshiping the ancestors, for recuperating himself and his wife, and for constructing his new house. All of these travels were long-distance ones. In terms of his travel routes, he frequently used royal main trunks, e.g. 'Haenamro' (from Seoul to Damyang), which were maintained by the royal government. The main reason of his frequent using of trunk lines was that convenience facilities such as the royal post stations (Yeok) and royal inns (Won) were equipped well in these roads so it was easy to get horse change services and lodging and boarding. The fact that main trunks were chiefly straight lines and the shortest way was rather secondary reason. On the other hand, when he was a superintendent of Junra province, he had four times of round inspection on all parishes of Junra province, following the tour routs covering all over the province. As he was incumbent royal officer, he started his travel by getting a permission from the king. Simultaneously, he made ready some travel items. Among the items, horse was most important one for the journey. After finishing all the preparing processes before the departure, he had special farewell ceremony for the King, Sookbae, and had a small party with his friends called Jeonbeul. Main transportation means for his travel was horse, and many kinds of horses such as royal government's horse, Yeokma, local government's horse, Swema, as well as his private one were used. Additionally, he used a palanquin while he was doing inspection trip as a superintendent of Junra province. Yu was incumbent officer so he mostly lodged in local government guest houses. If he could not find out any local guest house, he was lodged in royal inn, and in his relatives houses or irregularly in buddhist temples. Most meals were supplied by local royal governments. The activities in his journeys were varied on his travel objectives. In his private journey, it was the main activities that maintaining ancestor's tombs and having a memorial service. During the trip, he visited his relatives. His official trips, on the other hand, had a regularity. Main activities were dealing with public works, and visiting Hyanggyo (country public school). However in the midway, he visited his relatives and had a journey to scenic places.

Exploring Branch Structure across Branch Orders and Species Using Terrestrial Laser Scanning and Quantitative Structure Model (지상형 라이다와 정량적 구조 모델을 이용한 분기별, 종별 나무의 가지 구조 탐구)

  • Seongwoo Jo;Tackang Yang
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.26 no.1
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    • pp.31-52
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    • 2024
  • Considering the significant relationship between a tree's branch structure and physiology, understanding the detailed branch structure is crucial for fields such as species classification, and 3D tree modelling. Recently, terrestrial laser scanning (TLS) and quantitative structure model (QSM) have enhanced the understanding of branch structures by capturing the radius, length, and branching angle of branches. Previous studies examining branch structure with TL S and QSM often relied on mean or median of branch structure parameters, such as the radius ratio and length ratio in parent-child relationships, as representative values. Additionally, these studies have typically focused on the relationship between trunk and the first order branches. This study aims to explore the distribution of branch structure parameters up to the third order in Aesculus hippocastanum, Ginkgo biloba, and Prunus yedoensis. The gamma distribution best represented the distributions of branch structure parameters, as evidenced by the average of Kolmogorov-Smirnov statistics (radius = 0.048; length = 0.061; angle = 0.050). Comparisons of the mode, mean, and median were conducted to determine the most representative measure indicating the central tendency of branch structure parameters. The estimated distributions showed differences between the mode and mean (average of normalized differences for radius ratio = 11.2%; length ratio = 17.0%; branching angle = 8.2%), and between the mode and median (radius ratio = 7.5%; length ratio = 11.5%; branching angle = 5.5%). Comparisons of the estimated distributions across branch orders and species were conducted, showing variations across branch orders and species. This study suggests that examining the estimated distribution of the branch structure parameter offers a more detailed description of branch structure, capturing the central tendencies of branch structure parameters. We also emphasize the importance of examining higher branch orders to gain a comprehensive understanding of branch structure, highlighting the differences across branch orders.

A Study on the Location of Retail Trade in Kwangju-si and Its Inhabitants와 Effcient Utilization (광주시 소매업의 입지와 주민의 효율적 이용에 관한 연구)

  • ;Jeon, Kyung-sook
    • Journal of the Korean Geographical Society
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    • v.30 no.1
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    • pp.68-92
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    • 1995
  • Recentry the structure of the retail trade have been chanaed with its environmantal changes. Some studies may be necessary on the changing process of environment and fundamental structure analyses of the retail trade. This study analyzes the location of retail trades, inhabitants' behavior in retail tredes and their desirable utilization scheme of them in Kwangju-si. Some study methods, contents and coming-out results are as follows: 1. Retail trades can be classified into independent stores, chain-stores (supermarket, voluntary chain and frenchiise system and convenience store), department stores, cooperative associations, traditional, markets mail-order marketing, automatic vending and others by service levels, selling-items, prices, managements, methods of retailing and store or nonstore type. 2. In Kwangju, the environment of retail trades is related to the consumers of population structure: chanes in consumers pattern, trends toward agings and nuclear family, increase of leisur: time and female advances to society. Rapid structural shift in retail trade has also been occurred due to these social changes. Traditionl and premodern markets until 1970s altere to supermarkets or department stores in 1980s, and various types, large enterprises and foreign capitals came into being in 1990s. 3. The locational characteristics of retail trades are resulted from the spatial analysis of the total population distribution, and from the calculation of segregation index in the light of potential demand. The densely-populated areas occurs in newly-built apartment housing complex which is distributed with a ring-shaped pattern around the old urban core. The numbers and rates of the aged over sixty in Kwangsan-gu and the circumference area of Mt.Moodeung, are larger and higher where rural elements are remarkable. A relation between population distribution and retail trade are analysed by the index of population per shop. The index of the population number per shop is lower in urban center, as a whole, being more convenient for consumers. In newly-formed apartment complex areas, on the other, the index more than 1,000 per shop, meeting not the demands for consumers. Because both the younger and the aged are numerous in these areas, the retail trade pattern pertinent to both are needed. Urban fringes including Kwangsan-gu and the vicinity of Mt.Moodeung have some problems owing to the most of population number per shop (more than 1, 500) and the most extensive as well. 4. The regional characteristic of retail trade is analyzed through the location quotient of shops by locational patterns and centerality index. Chungkum-dong is the highest-order central place in CBD. It is the core of retail trades, which has higher-ordered specialty store including three big department stores, supermarkets and large stores. Taegum-dong, Chungsu-dong, Taeui-dong, and Numun-dong that are neiahbored to Chungkum-dong fall on the second group. They have a central commercial section where large chain stores, specialty shopping streets, narrow-line retailing shops (furniture, amusement service, and gallary), supermarkets and daily markets are located. The third group is formed on the axis of state roads linking to Naju-kun, Changseong-kun, Tamyang-kun, Hwasun-kun and forme-Songjeong-eup. It is related to newly, rising apartment housing complex along a trunk road, and characterized by markets and specialty stores. The fourth group has neibourhood-shopping centers including older residential area and Songjeong-eup area with independent stores and supermarkets as main retailing functions. The last group contains inner residential area and outer part of a city including Songjeong-eup. Outer part of miscellaneous shops being occasionally found is rural rather than urban (Fig. 7). 5. The residents' behaviors using retail trade are analyzed by factors of goods and facilities. Department stores are very high level in preference for higher-order shopping-goods such as clothes for full dress in view of both diversity and quality of goods(28.9%). But they have severe traffic congestions, and high competitions for market ranges caused by their sma . 64.0% of respondents make combined purpose trips together with banking and shopping. 6. For more efficiency of retail-trading, it is necessary to induce spatial distribution policy with regard to opportunity frequency of goods selection by central place, frontier regions and age groups. Also we must consider to analyze competition among different types of retail trade and analyze the consumption behaviors of working females and younger-aged groups, in aspects of time and space. Service improvement and the rationalization of management should be accomplished in such as cooperative location (situation) must be under consideration in relations to other functions such as finance, leisure & sports, and culture centers. Various service systems such as installment, credit card and peremium ticket, new used by enterprises, must also be carried service improvement. The rationalization and professionalization in for the commercial goods are bsically requested.

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The Relation Between Work-Related Musculoskeletal Symptoms and Rapid Upper Limb Assessment(RULA) among Vehicle Assembly Workers (자동차 조립 작업자들에서 상지 근골격계의 인간공학적 작업평가(Rapid Upper Limb Assessment) 결과와 자각증상과의 연관성)

  • Kim, Jae-Young;Kim, Hae-Joon;Choi, Jae-Wook
    • Journal of Preventive Medicine and Public Health
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    • v.32 no.1
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    • pp.48-59
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    • 1999
  • Objectives. This study was conducted to evaluate the association between upper extremity musculoskeletal symptoms and Rapid Upper Limb Assessment(RULA) in vehicle assembly line workers. The goal of this study is to show the feasibility of RULA as a checklist for work related musculoskeletal symptoms (WMSDs) in Korean workers. Methods. The total number of 199 people from the department of assembly and 115 people from the department of Quality Control(QC) in automotive plant were subjects for this cross sectional study. A standard symptom questionnaire survey has been used for the individual characteristics, work history, musculosketal symptoms and non-occupational covariates. The data were obtained by applying one-on-one interview for the all subjects. RULA has been applied for ergonomic work posture analysis and the primary ergonomic risk sure was computed by RULA method. Association between upper extremity musculoskeletal symptoms and RULA were assessed by multiple logistic regression analysis. Results. A total of 314 workers was examined. The prevalence of musculoskeletal symptoms by NIOSH case definition was 62.4%. The distribution of musculoskeletal symptoms by the part of the body turned out to be following; back:41.4%, neck: 32.8%, shoulder: 26.4%, arm: 10.5% and hand:29.3%. The relationship of the individual RULA scores were statistically significant for the prevalence of musculoskeletal symptoms. As the result of the multiple logistic regressioin analysis, grand final score (OR=2.250 95% CI: 1.402-3.612) was associated with musculoskeletal symptoms in any part of the body.; upper arm score(OR=1.786 95% CI: 1.036-3.079) and posture score A(OR=1.634 95% CI: 1.016-2.626) in neck; muscel use score(OR=3.076 95% CI:1.782-5.310) and posture score A(OR=1.798 95% CI: 1.072-3.017) in shoulder; upper arm score(OR=1.715 95% CI: 1.083-2.715) and muscel use score(OR=2.057 95% CI:1.303-3.248) in neck & shoulder; muscle use score(OR=10.662 95% CI: 3.180-35.742) in arm; writst/wist score(OR=2.068 95% CI: 1.130-3.786) and muscle use score(OR=2.215 95% CI: 1.284-3.819) in hand & wrist.; muscle use score of trunk (OR=2.601 95% CI: 1.147-5.901) in back. Conclusions. Musculoskeletal symptoms of the extremities were strongly associated with individual RULA body score. These results show that RULA can be used as a useful assessment tool for the evaluation of musculoskeletal loading which is known to contribute to work-related musculoskeletal disorders. RULA also can be used as a screening tool or incorporated into a wider ergonomic assessment of epidemiological, physical, mental, environmental and organizational factors. As shown in this study, complement of the analysis system for the other risk factors and characterizing between the upper limb and back part will be needed for future work.

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Studies of the Properties of Commercial Woods Grown in the Southern Part of Korea (한국산(韓國産) 유용목재(有用木材)의 기초재질(基礎材質)에 관(關)한 연구(硏究))

  • Chung, Byung-Jae;Lee, Jyung-Seuk;Kim, Yoon-Soo
    • Journal of the Korean Wood Science and Technology
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    • v.6 no.2
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    • pp.3-19
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    • 1978
  • Five species, Abies koreana Wilson (A. koreana), Castanopsis cuspidata var. Sieboldii Nakai (C. Cuspidata). Machilus thunbergii Sieb. et Zucc. (M. thunbergii), Styrax japonica (S. japonica), and Quercus acuta Thunberg(Q. acuta) growing in the southern part of Korea were selected for the investigation of wood properties. In order to evaluate the wood properties of these five species, anatomical, physical, mechanical, chemical and pulping characteristics were investigated. And this study also covered wood technological problems related to the drying, gluing, debarking, flooring, and wood workability so that these species might serve to the best advantage. The results obtained were summarized as follows: 1. The trunk of A. koreana with many knots was straight. However, the trunks of S. japonica and C. cuspidata were crooked. 2. A. koreana showed the longest and the widest ill the fiber morphology; 2.97mm in length, 39.3${\mu}$ in width. In general, fiber width of all the species investigated were greater than those of other Korean hardwoods. 3. The specific gravity of Q. acuta was 0.74${\pm}$0.03, and that of A.koreana was 0.34${\pm}$0.02. The range of specific gravity of the other species was 0.47-0.52. 4. The adsorption of water was propotioned inversely with the specific gravity, but the adsorption of humidity was proportioned with the specific gravity. In spite of their medium density, S. japonica showed the greatest adsorption, and M. thunbergii the least. The water adsorption of cross section was twice greater than that of lateral direction, and there was a slight difference in between the radial and the tangential direction. 5. Shrinkage for tested five species was ranged from 5.36 to 10.24% in tangential direction, and 2.83~6.13% in radial direction. Q. acuta recorded the greatest shrinkage rate, and A. koreana the least. The greater was the specific gravity, the larger was the shrinkage rate. 6. The mechanical properties of Q. acuta were similar to those of Quercus mongolica which grow in Kangwon-Do. Strength properties of C. cuspidata, M. thunbergii, A. koreana were equivalent to those of other Korean commercial woods with similar specific gravity, except S. japonica which showed slightly higher strength than that of other species with similar density. 7. Higher glue joint strength for urea and phenol adhesieves was recorded in the species of M. thunbergii and C. cuspidata, however, high-density species(Q. acuta) and even low-density species(A. koreana) did not show good joint strength. 8. The attractive figure of M. thunbergii in texture seemed to he appreciated for decoration. And the grain and texture of other species were proper for furniture and building materials. 9. All of the species except Q. acuta were considered good for wood workability. 10. The denser the specific gravity was, the longer the drying time took. However, severe drying defects were formed in M. thunbergii whose density was medium. 11. All the species were considered suitable for the flooring wood expect A. koreana whose density was light. 12. Pentosan component in all the species was great, and the amount of extractives in Q. acuta was worth noticing. 13. Yield in kraft pulp was above the level of economic pulp yield, i.e. 45% in all species. 14. Debarking was easy in the species of A. koreana and M. thunbergii, and debarking after being boiled in water was the most efficient in all species.

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