• 제목/요약/키워드: Mortality of tree

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토양 및 식생변화에 따른 토지 사방 공사의 효과에 관한 연구 (Erosion Control Effect by Soil ansi Vegetation Transition in Mountainous Area after Soil Erosion Measures were Initiated)

  • 이천용
    • 한국조경학회지
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    • 제14권2호
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    • pp.7-16
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    • 1986
  • 산지사방공사후 시공년수 경과에 따른 토양 및 식생의 변화로서 사방효과를 구명하기 위하여 전국의 대규모 황폐지에 36개소의 plot를 설정하여 사방시공년차별로 식생의 피복도와 출현종 상장 및 토양을 조사하기는 시공후 7년으로 이후 임관의 소개가 필요하다. 1) 하중인관과 상층식생의 피복도가 가장 적당한 시공후 7년으로 이후 인관의 소개가 필요하다. 2) 하층식생의 종수는 임관울폐직전인 6년까지 증가하다가 울폐후 감소하였다. 3) 수고생장은 아까시나무, 물오리나무, 리기다소나무 순으로 좋았으며 이까시나무는 초기에 왕성한 생장을 보이다 계속 감소하였고, 물오리나무는 시공후 12토양내 양료부족이 가장 큰 원인으로 나타났다. 4) 사방수종은 식재후 8년내에 약 50%가 고사하였는데 물오리나무와 아까시나무는 그 후에는 계속 잔존본수가 감소하였고 리기다소나무는 시공10년후부터 ha당 500 본을 유지하였다. 5) 시공년수가 경과할수록 풍화토실이 깊어지고 견밀도가 낮아져 시공후 14년에는 토양의 물리적인 성질이 어느정도 개량되었다. 6) 토양내 pH는 시공직후 5.3에서 20년에는 5.1로 낮아지는 경향을 보였다. 7) 유기적과 질소함량은 시비의 영향으로 3년까지 급증하다가 그 후부터는 점증하였다. 그러나 임목생육에 필요한 양에는 20년이 되어도 부족한 것으로 나타났다. 8) 토양내인산함량은 초기에는 시비의 영향으로 높았으나 급격히 감소하여 시공후 5년부터는 절대량이 부족하므로 지속적인 시비가 요구된다. 9) 물질생산량은 아까시나무가 가장 많은 양을 보이면서 20년까지 계속 증가한 반면 물오리나무는 15년간부터 감소하여 갱신이 요구도며 20년된 사방시 1ha의 지상부총물질생산량은 105.7 ton이었다.>$\ulcorner$표현$\lrcorner$의 모습으로, 반면에 농촌취락들에서는 자연의 조건에 공존 또는 의존하는 모습의 $\ulcorner$순응$\lrcorner$적 특성을 나타내게 된다. 우리나라의 취락에 게재된 $\ulcorner$순응$\lrcorner$이란 큰 특징은 풍수적 개념 드에 의해 이루어졌던 형태이다. 그리하여 때로는 민담에서도 풍수가 주제가 되는 경우가 있고, 일반적으로는 역사적 사실이나 인물을 통하여 취락민이지녀온 자연요소에 대한 인식관 또는 그러한 생활에서 나타나는 윤리관 등이 암암리에 표현되기도 한다. 민담을 통하여 우리는 주민들 의식 속에 남아있는 취락의 중요한 요소나 장소들을 찾아볼수 있고 더불어 이들을 중심으로 이루어 졌을지도 모를 생활모습들을 생각해볼 수 있다. 이러한 것들은 $\ulcorner$순응$\lrcorner$의 다른 일면 또는 때에 따라서는 극히 의도적인 $\ulcorner$표현$\lrcorner$적인 한 면모 - 그 대표적인 경우로 정원을 구성하는데 개재된 인간의 의미는 무언가를 표현 또는 표출하고자 함에 있다는 점 -라 볼수도 있을, 예로써 성리학적 사고관념으로써 집과 정사 그리고 주변 경관을 자신의 내적본직 또는 윤리적 영역으로 삼아 묘사.표현.구체화 시켜가기도 한다. 최소한 동족부락의 한두 예들에서 그러한 $\ulcorner$표현$\lrcorner$적 의도에 의한 경관구성의 일면을 확인할수 있지만 엄밀히 생각하여 보면 이러한 예의

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흰불나방 핵다각체병 바이러스의 제제화에 관한 시험 (Experiment of the formulation for the viral pesticide of nuclear polyhedrosis virus of the fall webworm, Hyphantria cunea Drury.)

  • 진병래;김권영;강석권
    • 한국잠사곤충학회지
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    • 제29권2호
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    • pp.51-57
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    • 1987
  • 흰불나방의 미생물적 방제를 위한 핵다각체병 바이러스의 제제화와 그 실용화를 위한 야외 살포 시험을 통해 얻어진 제제의 불활화 정도 및 살포효과는 다음과 같다. 흰불나방 핵다각체병 바이러스의 불활화 조사에서 부유액의 경우 야외 살포후 5일이 경과한 후로는 완전히 불활화 되었으며, 제제는 살포 후 20일이 지나서 완전히 불활화 되어, 흰불나방 핵다각체병 바이러스를 제제화 했을 때 부유액에 비해 약 10-15일 정도 활성을 보유하여 제제의 안전성을 확인하였다. 또 제제의 야회 살포효과 시험에서 부유액의 경우는 2일이 경과하면서 병원성을 보이지 않은 반면에 제제는 접종당일 살포하였을 때 약 50%정도의 폐사율을 나타내었으며, 살포 후 9일까지는 약 30% 정도의 폐사율을 유지하면서 비교적 안전성을 보이다가 살포 후 14일이 경과하면서 병원성을 보이지 않았다. 제제의 경우 야외에서 약 10일 이상 감염력의 지속에 의한 살포효과를 나타내었다.

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Spatial Pattern of Larix gmelini in a Spruce-fir Valley Forest of Xiaoxing'an Mountains, China

  • Jin, Guangze;Liu, Liang;Liu, Zhili;Kim, Ji-Hong
    • 한국산림과학회지
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    • 제99권5호
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    • pp.720-725
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    • 2010
  • On the basis of vegetation data in the 9.12 ha (380 m ${\times}$ 240 m) permanent sample plot of the spruce-fir valley forest in Liangshui National Reserve of Xiaoxing'an Mountains, the study was conducted to evaluate spatial distribution pattern and spatial association by using point pattern analysis for living and dead trees of Larix gmelini by DBH size class. The number of L. gmelini were counted as 59 living stems/ha (6.42 $m^2$/ha of basal area) and 34 dead stems/ha (2.86 $m^2$/ha of basal area). The distributional curve of diameter class exhibited bimodal shape. The analysis of spatial distribution patterns of all living larch stems noted the clumped distribution on the whole. The size of larch aggregates of dead stems was decreased as diameter class was increased. The distribution of dead stems became gradually randomized with decreased clumped size as the scale increased. Living stems and dead stems of the larch had positive spatial association at most of scales, illustrating that the occurrence of mortality of the larch tree was closely related to the distribution pattern of living larch trees.

Impact of Routine Histopathological Examination of Gall Bladder Specimens on Early Detection of Malignancy - A Study of 4,115 Cholecystectomy Specimens

  • Kalita, Dipti;Pant, Leela;Singh, Sompal;Jain, Gaurav;Kudesia, Madhur;Gupta, Kusum;Kaur, Charanjeet
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권5호
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    • pp.3315-3318
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    • 2013
  • Gall bladder carcinoma is the most common cancer of biliary tree, characterized by rapid progression and a very high mortality rate. Detection at an early stage, however, is indicative of a very good prognosis and prolonged survival. The practice of histopathological examination of gall bladder specimens removed for clinically benign conditions and its usefulness has been a subject of controversy. The present prospective study was carried out over a period of four years in order to find out the incidence of unsuspected gallbladder carcinoma in cholecystectomy specimens received in our histopathology laboratory and to analyze their clinico-pathological features. A total of 4,115 cases were examined. Incidentally detected cases comprised 0.44%, which accounted for 72% of all gall bladder carcinomas detected. The majority were in an early, surgically resectable stage. From the results of this study we recommend that in India and other countries with relatively high incidences of gall bladder carcinoma, all cholecystectomy specimens should be submitted to histopathology laboratory, as this is the only means by which malignancies can be detected at an early, potentially curable stage.

Insecticidal Activity of Japanese Pine Sawyer (Monochamus alternatus) and Pine Sawyer (Monochamus saltuarius) Using Abamectin and Emamectin benzoate

  • Lee, Dong-Hyeon;Suh, Dong Yeon;Seo, Sang-Tae;Lee, Sang-Hyun
    • Journal of Forest and Environmental Science
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    • 제36권3호
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    • pp.255-258
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    • 2020
  • Pine wilt disease (PWD) caused by pine wood nematode (PWN), Bursaphelenchus xylophilus, which is transmitted by Monochamus alternatus and M. saltuarius, is a serious threat to coniferous forests in the Northern Hemisphere, including Korea. The efficacy of abamectin and emamectin benzoate for preventing the PWD in the field and its effect on the vectors Monochamus alternatus and M. saltuarius (Coleoptera: Cerambycidae) were evaluated. An experimental plot was delimited, of which consists of Japanese red pine (Pinus densiflora) forest in South Korea, and trunk injection trials were made with abamectin and emamectin benzoate. Branches of each tree were collected, and are subsequently subjected to the analysis of residues for both nematicides. Results obtained in this study showed that abamectin and emamectin benzoate showed over 90% mortality at the recommended concentration after 6 days and 8 days, respectively. Consequently, it was found that both insecticides have a higher effect on the susceptibility and persistence of two vectors of PWD, M. alternatus and M. saltuarius feeding on branches of the trees, and its application by trunk injection is confirmed as an option for pine wilt disease management programs in Korea.

고혈압 예측을 위한 이상치 탐지 알고리즘 및 데이터 통합 기법 (An Outlier Detection Algorithm and Data Integration Technique for Prediction of Hypertension)

  • 홍고르출;김미혜 ;송미화
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2023년도 춘계학술발표대회
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    • pp.417-419
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    • 2023
  • Hypertension is one of the leading causes of mortality worldwide. In recent years, the incidence of hypertension has increased dramatically, not only among the elderly but also among young people. In this regard, the use of machine-learning methods to diagnose the causes of hypertension has increased in recent years. In this study, we improved the prediction of hypertension detection using Mahalanobis distance-based multivariate outlier removal using the KNHANES database from the Korean national health data and the COVID-19 dataset from Kaggle. This study was divided into two modules. Initially, the data preprocessing step used merged datasets and decision-tree classifier-based feature selection. The next module applies a predictive analysis step to remove multivariate outliers using the Mahalanobis distance from the experimental dataset and makes a prediction of hypertension. In this study, we compared the accuracy of each classification model. The best results showed that the proposed MAH_RF algorithm had an accuracy of 82.66%. The proposed method can be used not only for hypertension but also for the detection of various diseases such as stroke and cardiovascular disease.

A Study on the Comparison of Predictive Models of Cardiovascular Disease Incidence Based on Machine Learning

  • Ji Woo SEOK;Won ro LEE;Min Soo KANG
    • 한국인공지능학회지
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    • 제11권1호
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    • pp.1-7
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    • 2023
  • In this paper, a study was conducted to compare the prediction model of cardiovascular disease occurrence. It is the No.1 disease that accounts for 1/3 of the world's causes of death, and it is also the No. 2 cause of death in Korea. Primary prevention is the most important factor in preventing cardiovascular diseases before they occur. Early diagnosis and treatment are also more important, as they play a role in reducing mortality and morbidity. The Results of an experiment using Azure ML, Logistic Regression showed 88.6% accuracy, Decision Tree showed 86.4% accuracy, and Support Vector Machine (SVM) showed 83.7% accuracy. In addition to the accuracy of the ROC curve, AUC is 94.5%, 93%, and 92.4%, indicating that the performance of the machine learning algorithm model is suitable, and among them, the results of applying the logistic regression algorithm model are the most accurate. Through this paper, visualization by comparing the algorithms can serve as an objective assistant for diagnosis and guide the direction of diagnosis made by doctors in the actual medical field.

총상에 의한 경부 관통상 -치험 1례- (Penetrating Neck Trauma by Gunshot Injury: 1 Case Report)

  • 홍윤주
    • 한국응급구조학회지
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    • 제9권1호
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    • pp.95-99
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    • 2005
  • Penetrating neck trauma by gunshot injury involving tracheobronchial tree is rare in Korea. Extensive tissue damage by cavitation, tissue fragmentation and shock wave transmission of high-velocity projectile along with associated organ injury renders high rate of mortality and morbidity. A 28 year old man in military service with gunshot wound in left cervical area presented initial symptoms of severe dyspnea and subcutaneous emphysema. Computed tomography of chest and cervical region as well as bronchoscopic evaluation was performed to confirm highly suspected injury to cervical trachea. Surgical exposure was established through a low collar incision; the damaged segment of 3.5 cm length including 2-4th tracheal rings was resected out and end-to-end anastomosis was performed. Bleeding from lacerated anterior jugular vein was controlled by ligation of both ends and a K2 bulllet was found upon inner border of body of first rib, medial to right carotid sheath and removed out. Cervical esophagus, carotid artery, internal jugular vein and recurrent laryngeal nerve were spared. Extubation was done on the first postoperative day and postoperative course until discharge on nineth postoperative day remained uneventful.

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아메리카잎굴파리에 대한 항생제 살충제의 생존과 생식에 미치는 영향 (Effect of Antibiotics Insecticides on Survival and Reproduction of the Serpentine Leafminer, Liriomyza trifolii)

  • 이정은;서동규;김길하
    • 농약과학회지
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    • 제10권4호
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    • pp.329-334
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    • 2006
  • 본 연구는 시판되고 있는 4종의 항생제계통 살충제(abamectin, emamectin benzoate, spinosad=등록약제, milbemectin=미등록약제)에 대한 아메리카잎굴파리의 발육단계별 약제감수성을 조사하였다. 4약제 모두 알과 유충에 대해서 높은 살충효과를 나타내었으나, 번데기와 성충에 대해서는 낮은 살충효과를 나타내었다. 암컷성충의 산란억제 효과는 abamectin, emamectin benzoate, spinosad에서 100%를 나타내었으며, milbemectin은 85%의 산란억제율을 나타내었다. 섭식흔적수는 milbemectin을 제외하고는 크게 감소되었으며, 성충수명 역시 milbemectin을 제외하고 무처리의 평균 5.5일에 비하여 0.8-1.4일로 크게 단축되었다. 산란효과는 abamectin, emamectin benzoate 그리고 spinosad는 처리 후 7일까지 높았으나, milbemectin은 낮았다.

Comparing the Performance of 17 Machine Learning Models in Predicting Human Population Growth of Countries

  • Otoom, Mohammad Mahmood
    • International Journal of Computer Science & Network Security
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    • 제21권1호
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    • pp.220-225
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    • 2021
  • Human population growth rate is an important parameter for real-world planning. Common approaches rely upon fixed parameters like human population, mortality rate, fertility rate, which is collected historically to determine the region's population growth rate. Literature does not provide a solution for areas with no historical knowledge. In such areas, machine learning can solve the problem, but a multitude of machine learning algorithm makes it difficult to determine the best approach. Further, the missing feature is a common real-world problem. Thus, it is essential to compare and select the machine learning techniques which provide the best and most robust in the presence of missing features. This study compares 17 machine learning techniques (base learners and ensemble learners) performance in predicting the human population growth rate of the country. Among the 17 machine learning techniques, random forest outperformed all the other techniques both in predictive performance and robustness towards missing features. Thus, the study successfully demonstrates and compares machine learning techniques to predict the human population growth rate in settings where historical data and feature information is not available. Further, the study provides the best machine learning algorithm for performing population growth rate prediction.