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Quantitative Comparisons of Soil Carbon and Nutrient Storage in Larix leptolepis, Pinus densiflora and Pinus rigitaeda Plantations

  • Kim, Choonsig;Cho, Hyun-Seo
    • The Korean Journal of Ecology
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    • v.27 no.2
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    • pp.67-71
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    • 2004
  • This study was carried out to evaluate soil carbon and nutrient storage of three adjacent coniferous plantations (Larix leptolepis, Pinus densiflora and Pinus rigitaeda) growing on a similar site with a same planting age (42-year old) in the Sambong Exhibition Forests, Hamyang-gun, Gyungsangnam-do. The soil carbon concentration among three plantations was not significantly different in 0∼10cm soil depth, but other two depths (10∼20cm and 20∼30cm) showed higher carbon concentration in P. densiflora plantation than the other two plantations. The exchangeable cation concentrations (Ca and Mg) in 0∼10cm depth were significantly lower in L. leptolepis plantation than in the other two plantations, while nitrogen and phosphorus concentrations were not significantly different among three plantations except for nitrogen at 10∼20cm depth in P. rigitaeda plantation. Soil carbon storage in 0∼20cm depth of three plantations was unaffected by the stand types. Soil nutrient storage was not significantly different at each depth except for nitrogen storage at 10∼20cm depth in P. rigitaeda plantation because of the variation of bulk density and coarse fragment. This result demonstrates that soil carbon and nutrient concentrations among the plantations on a similar soil condition can be altered significantly by tree species effects over 40 years after plantation establishment.

A Computer Program for Stem Analysis (수간석해(樹幹析解)의 전산화(電算化) 프로그램 개발(開發))

  • Cho, Eung Hyouk
    • Journal of Korean Society of Forest Science
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    • v.69 no.1
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    • pp.6-12
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    • 1985
  • A computer program for stem analysis has been prepared by using BASIC language. Annual-ring counts and other input data can be directly entered for necessary calculation, and outputs are data lists, cross-section areas, age-height relationships, growth rates, total, annual, and mean increments of height, D.B.H. and volume for an individual tree. The sectional log volumes are calculated by Huber's formula, and the growth rates by Pressler's in this program. A copy of the program listing is in appendix I.

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IgE-mediated food allergies in children: prevalence, triggers, and management

  • Lee, Sooyoung
    • Clinical and Experimental Pediatrics
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    • v.60 no.4
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    • pp.99-105
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    • 2017
  • Food allergy (FA) is a serious health problem, and severe FA such as food-induced anaphylaxis can often be life threatening. The incidence of FA has been increasing especially in children. They usually develop early in life and affect up to 10% of children. The 2 most common food allergens worldwide are milk and eggs, while the third one varies depending on the countries: peanuts in the United States and Switzerland, wheat in Germany and Japan, tree nuts in Spain, sesame in Israel, and walnuts in Korea. These common food allergens are different and difficult to identify because of differing study methodologies, population, geography, age, and dietary exposure patterns. The current management of FA relies on the strict avoidance of culprit allergens, the prompt treatment of allergic reactions, including epinephrine use for food-induced anaphylaxis, monitoring, and education to prevent further reactions. Newer approaches for tolerance induction to FA and FA immunotherapy have been under investigation but are not yet ready for real-world application. Thus, consistent and systematic education of patients, caregivers, and food-handling people is of primary importance for the management and prevention of FA reactions. This review assesses and compares IgE-mediated FA in children in Korea and other countries, with a focus on summarizing the prevalence, common triggers, and management of FA.

Theory and Practice of Cover Crops Growing in Orchard (과수원 피복작물 재배의 이론과 실제)

  • 송기철
    • Korean Journal of Organic Agriculture
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    • v.9 no.4
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    • pp.95-111
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    • 2001
  • To carry out the Integrated Fruit Production(IFP), researches on cover crops as well the Integrated Pest Management(IPM) and the Integrated Nutrition Management(INM) should be very important. These concepts are neither clear nor connective till now. The researches on cover crops in Europe and USA are being kept within the category of IFP. Main researches on fruit trees for sustainable agriculture in Italy are new variety creation, development of growing techniques, pest and disease control, and cover crops management, etc. It is necessary of fruit industry in Korea to maintain good quality and taco-friendly fruit production. For this goal, we need international cooperation with highly developed countries in Europe. In first step, we should enlarge research areas and analyze results obtained to get farmers understood the concept of cover crop growing, Furthermore, we make researches more profoundly on cover crops growing considering tree age, mixing rates among cover crops, seeding and cutting time for cover crops, and so on. Researchers, specialists of agricultural extensions, and farmers should concentrate their opinions and conduct IFP together. The IFP should go on systematically and reach finally to get certificates internationally by the International Organization for Biological and integrated Control of Noxious Animals and Plants(IOBC) to enhance selling and exporting fruits.

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Ecological Studies on the Distribution, Structure and Maintenance Mechanism of Berchemia berchemiaefolia Forest (망개나무林의 分布, 構造 및 維持機作)

  • Kang, Sang-Joon;Hong-Eun Kim;Chang-Seok Lee
    • The Korean Journal of Ecology
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    • v.14 no.1
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    • pp.25-38
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    • 1991
  • Berchemia berchemiaefolia is a native a native rare plant which has been designating as the Natural Monument, No. 266, since 1980. The floristic composition, population structure and maintenance mechanism of the Berchemia berchemiaefolia forest were investigated in conjunction with the habitat consisted of the block field or screes. Through the present study, the authors found a new habitat of Berchemia berchemiaefolia in the northeastern slope on Mt. Kumdansan located at Hajeok-ri, Cheongcheon-myeon, Koesan-gun, chungbuk province. Gravels consisted of the block field belonged to granule, pebble and cobble as the range of grain size, $\Phi$=-1.5~6.6 values. The tree layer of Berchemia berchemiaefolia community was mainly composed of Quercus variabilis, Pinus densiflora and Q. serrata including Berchemia berchemiaefolia and of this community were similar to that of Q. variabilis. By the age distribution, it was considered that the community was a discontinued one as the pattern of distribution was a normal distribution type(N type). Phenological cycle including leafing, blooming and seed-bearing period between both sites of block field and valley or close canopy showed some differences. The seed production of Berchemia berchemiaefolia was 8, 655, 000 seeds/ha/year, but only 406, 000 seeds/ha/year of them were developed as saplings, and only 4 saplings were developed to mature trees.

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Studies on the Actual Vegetation and Vegetation Structure of the Tongdosa Temple Forest

  • Kang, Hyun-Mi;Lee, Sang-Cheol;Choi, Song-Hyun;Park, Seok-Gon
    • Korean Journal of Environment and Ecology
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    • v.29 no.1
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    • pp.46-61
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    • 2015
  • The purpose of this study is to investigate a vegetation structure around Tongdosa temple forest and provincial park and to provide preliminary data. In order to look over the vegetation status, an actual vegetation map was drawn around study area. Vegetation structure survey was carried out for 6 representative communities of actual vegetation which were Quercus variavilis community, Carpinus tschonoskii community, Pinus densiflora community, P. densiflora-Broadleaf deciduous Forest community, Q. mongolica community and Broadleaf deciduous Forest community. The area of the Tongdosa district measured $29,202,262m^2$. Actual vegetation type were divided into 35 types, and the ratio of Q. variavilis community was 32.35 % ($9,447,932m^2$). To investigate the structure of 6 representative communities, 58 plots were set up and unit area plots measured $100m^2$. The estimated age of the forest is 50~100-years-old and the oldest tree P. densiflora is 113-years-old.

A Case of Cholangiocarcinoma Arising from Type I Choledochal Cyst in a 13-year-old Girl (13세 여아에서 발생한 총담관낭 I형에서 기원한 담관암 1례)

  • Ahn, Sung-Ryon;Nam, Sang-Ook;Park, Jae-Hong;Lim, Young-Tak;Lee, Jun-Woo;Lee, Chang-Hun
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.5 no.1
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    • pp.113-117
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    • 2002
  • Choledochal cyst is a rare developmental malformation of the biliary tree and has serious problem of transformation to malignancy. The development of cholangiocarcinoma related to choledochal cyst increases as the age of patient increases and is more common in Orientals with female predominance of 2.5 times. Prevalence rate of cholangiocarcinoma is various from 2.5 to 15.6% in adult with choledochal cyst, but very low in children. We experienced a case of cholangiocarcinoma with multiple liver metastases arising from type I choledochal cyst in a 13-year-old girl who complained of sudden onset of right upper quadrant abdominal pain.

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A Study on the Apple Production of Kyungpook Region and Regional Comparison between other regions of Korea (경북지역의 사과 생산변동과 여타지역과의 생산비교)

  • Ryu, Jin Chun;Shin, Young Bum
    • Current Research on Agriculture and Life Sciences
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    • v.13
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    • pp.55-64
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    • 1995
  • Apple is most favorable fruit in Korea, and apple farmland has been increased before and after the agreements of Uruguay Round and apple is considered as one of strategic agricultural goods. Especially expansion of apple farmland is concentrated in Kyungpook region because of the suitable climate and its market share is about 70 percents in 1992. But in tree age of apple, although newly and replanting area is increasing, the rate of old orchards is higher than that of other regions. In varieties of apple, it is concentrated in Fuji and is forecasted to increase in the future. The amount of apple production of Kyungpook region is 480 thousand tons, that is concentrated in Wui-sung, Young-ju and An-dong. The quantity of apple production per 10a. is 1,315kg, that is low level compared with that of America and Japan, and the gap of technology among farmers is heavily. The difficulties of apple farming in Kyungpook region are summarized as follows. first, the lack of mechanization and facilities due to the small scale of farmland, second, lack of rural labor force, third, concentration on Fuji apple varieties, fourth, low productivity of apple farming.

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Corporate Corruption Prediction Evidence From Emerging Markets

  • Kim, Yang Sok;Na, Kyunga;Kang, Young-Hee
    • Asia-Pacific Journal of Business
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    • v.12 no.4
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    • pp.13-40
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    • 2021
  • Purpose - The purpose of this study is to predict corporate corruption in emerging markets such as Brazil, Russia, India, and China (BRIC) using different machine learning techniques. Since corruption is a significant problem that can affect corporate performance, particularly in emerging markets, it is important to correctly identify whether a company engages in corrupt practices. Design/methodology/approach - In order to address the research question, we employ predictive analytic techniques (machine learning methods). Using the World Bank Enterprise Survey Data, this study evaluates various predictive models generated by seven supervised learning algorithms: k-Nearest Neighbour (k-NN), Naïve Bayes (NB), Decision Tree (DT), Decision Rules (DR), Logistic Regression (LR), Support Vector Machines (SVM), and Artificial Neural Network (ANN). Findings - We find that DT, DR, SVM and ANN create highly accurate models (over 90% of accuracy). Among various factors, firm age is the most significant, while several other determinants such as source of working capital, top manager experience, and the number of permanent full-time employees also contribute to company corruption. Research implications or Originality - This research successfully demonstrates how machine learning can be applied to predict corporate corruption and also identifies the major causes of corporate corruption.

Analysis of Healthcare Quality Indicator using Data Mining and Decision Support System

  • Young M.Chae;Kim, Hye S.;Seung H. Ho
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2001.01a
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    • pp.352-357
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    • 2001
  • This study presents an analysis of healthcare quality indicators using data mining for developing quality improvement strategies. Specifically, important factors influencing the inpatient mortality were identified using a decision tree method for data mining based on 8,405 patients who were discharged from the study hospital during the period of December 1, 2000 and January 31, 2001. Important factors for the inpatient mortality were length of stay, disease classes, discharge departments, and age groups. The optimum range of target group in inpatient healthcare quality indicators were identified from the gains chart. In addition, a decision support system was developed to analyze and monitor trends of quality indicators using Visual Basic 6.0. Guidelines and tutorial for quality improvement activities were also included in the system. In the future, other quality indicators should be analyze to effectively support a hospital-wide continuous quality improvement (CQI) activity and the decision support system should be well integrated with the hospital OCS (Order Communication System) to support concurrent review.

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