• Title/Summary/Keyword: Period

Search Result 57,079, Processing Time 0.088 seconds

Distributional Characteristics and Population Substantiality of Viola mirabilis L.; Rear edge Population in Korea (한국이 후방가장자리 개체군인 넓은잎제비꽃(Viola mirabilis L.)의 분포특성과 지속가능성)

  • Chae, Hyun-Hee;Kim, Young-Chul;An, Won-Gyeong;Kwak, Myoung-Hai;Nam, Gi-Heum;Lee, Kyu-Song
    • Korean Journal of Environment and Ecology
    • /
    • v.33 no.4
    • /
    • pp.422-439
    • /
    • 2019
  • The rear edge population is considered to have low genetic diversity and high risk of extinction according to a highly isolated distribution. However, the rear edge population is observed to have persisted for an extended period despite the low genetic diversity. As such, it is necessary to understand the ecological process involved in the persistence of the population. Viola mirabilis L. in Korea is considered the rear edge population from the perspective of the worldwide distribution. We surveyed the distribution range of V. mirabilis, which shows the isolated distribution in the central area of Korea, to find out the factors of its persistence. Next, we investigated and accessed the vegetational pattern of habitats, soil environment, phenology, self-compatibility, population structure, and extinction risk factors observed in the distribution area. V. mirabilis was distributed in the understory of the deciduous forest, planted forest of the deciduous conifer and deciduous broad-leaved trees, shrubland, and grassland in the limestone area. We also observed the re-establishment of seedlings in the population, and most of them showed a stable population structure. For chasmogamous flowers, the visit by pollinators has a significantly positive relationship with the production of fruits. However, we found that the production of the cleistogamous flowers was more numerous in all studied populations and that only the cleistogamous flowers were produced despite a more substantial plant size in some populations. The plant size was more related to the production of the cleistogamous flowers than that of the chasmogamous flowers. Accordingly, the cleistogamous flowers significantly contributed to seedling recruitment in the population. We found that the production of the chasmogamous flowers and the cleistogamous flowers did not have a correlation with the factors of the soil analysis except for phosphoric acid. V. mirabilis showed the self-incompatibility characteristics most likely due to the production capability of the cleistogamous flowers. Potential extinction risk factors observed in the distribution area was included the development of limestone mine, the expansion of agricultural fields, and the construction of houses. Although V. mirabilis showed an isolated distribution in the limestone area in the Korean peninsula, it showed a diverse distribution in a wide habitat environment ranging from the grassland to the understory of the trees with relatively low canopy closure rate. Moreover, we concluded that the persistence of the population was possible if we can maintain the current state of multiple populations and stable population structure.

Evolution of Aviation Safety Regulations to cope with the concept of data-driven rulemaking - Safety Management System & Fatigue Risk Management System

  • Lee, Gun-Young
    • The Korean Journal of Air & Space Law and Policy
    • /
    • v.33 no.2
    • /
    • pp.345-366
    • /
    • 2018
  • Article 37 of the International Convention on Civil Aviation requires that rules should be adopted to keep in compliance with international standards and recommended practices established by ICAO. As SARPs are revised annually, each ICAO Member State needs to reflect the new content in its national aviation Acts in a timely manner. In recent years, data-driven international standards have been developed because of the important roles of aviation safety data and information-based legislation in accident prevention based on human factors. The Safety Management System and crew Fatigue Risk Management Systems were reviewed as examples of the result of data-driven rulemaking. The safety management system was adopted in 2013 with the introduction of Annex 19 and Chapter 5 of the relevant manual describes safety data collection and analysis systems. Through analysis of safety data and information, decision makers can make informed data-driven decisions. The Republic of Korea introduced Safety Management System in accordance with Article 58 of the Aviation Safety Act for all airlines, maintenance companies, and airport corporations. To support the SMS, both mandatory reporting and voluntary safety reporting systems need to be in place. Up until now, the standard of administrative penal dispensation for violations of the safety management system has been very weak. Various regulations have been developed and implemented in the United States and Europe for the proper legislation of the safety management system. In the wake of the crash of the Colgan aircraft, the US Aviation Safety Committee recommended the US Federal Aviation Administration to establish a system that can identify and manage pilot fatigue hazards. In 2010, a notice of proposed rulemaking was issued by the Federal Aviation Administration and in 2011, the final rule was passed. The legislation was applied to help differentiate risk based on flight according to factors such as the pilot's duty starting time, the availability of the auxiliary crew, and the class of the rest facility. Numerous amounts data and information were analyzed during the rulemaking process, and reflected in the resultant regulations. A cost-benefit analysis, based on the data of the previous 10 year period, was conducted before the final legislation was reached and it was concluded that the cost benefits are positive. The Republic of Korea also currently has a clause on aviation safety legislation related to crew fatigue risk, where an airline can choose either to conform to the traditional flight time limitation standard or fatigue risk management system. In the United States, specifically for the purpose of data-driven rulemaking, the Airline Rulemaking Committee was formed, and operates in this capacity. Considering the advantageous results of the ARC in the US, and the D4S in Europe, this is a system that should definitely be introduced in Korea as well. A cost-benefit analysis is necessary, and can serve to strengthen the resulting legislation. In order to improve the effectiveness of data-based legislation, it is necessary to have reinforcement of experts and through them prepare a more detailed checklist of relevant variables.

The Growth Performances and Soil Properties of Planted Zelkova serrata Trees according to Fertilization in Harvested Pinus rigida Plantation over 6 Years after Planting (조림지 시비 처리에 따른 리기다소나무 벌채지 내 식재 6년 후 느티나무 조림지 토양 및 조림목 생장 특성)

  • Yang, A-Ram;Cho, Min Seok
    • Journal of Korean Society of Forest Science
    • /
    • v.108 no.1
    • /
    • pp.29-39
    • /
    • 2019
  • The objective of this study was to suggest a suitable amount of fertilizer using the changes in growth performances and soil properties for improving survival and quality of Zelkova serrata trees in a harvested Pinus rigida plantation. One-year-old containerized seedlings of Z. serrata were planted with the density of 3000 seedlings $ha^{-1}$ in end of March 2011 at Gwangneung experimental forest, Pocheon. Solid compound fertilizer (N:P:K=3:4:1) were applied yearly in three amounts (control: no fertilization, F1: $180kg\;ha^{-1}$, and F2: $360kg\;ha^{-1}$) every May from 2011 to 2013. We analyzed soil properties before (2011) and after (2012 and 2017) fertilization. And we measured the root collar diameter and height of Z. serrata trees from 2011 to 2016, and then calculated H/D ratio and stem volume. Soil properties at Z. serrata plantation did not show difference according to fertilization level in every investigation year. As time passed after planting, however, concentrations of total nitrogen and available phosphorus were increased from decreased. The growth of root collar diameter, height and stem volume of Z. serrata trees at F2 plot were significantly higher those at the other plots after only 2 years of fertilization. Because Z. serrata tree demand to more nutrient during the early growing period. The survival rate of Z. serrata trees at control plot was significantly lower than that at the other plots. This might be due to Z. serrata trees at control plot had not the upper hand from competition with vegetation at the early in planting. However, the growth of height and stem volume of Z. serrata trees between F1 and F2 plots did not show difference over 6 years after planting. Consequently, we could suggest that Z. serrata trees need to F1 fertilization level for considering improving survival and quality of Z. serrata trees and economical efficiency of plantation managements after harvesting P. rigida plantation.

Function and Use Evaluation of 'Classification & Disposal Schedule Management' in the Standard Records Management System (표준 기록관리시스템의 '기준관리' 기능 및 이용 평가)

  • Chung, Sang-hee
    • The Korean Journal of Archival Studies
    • /
    • no.37
    • /
    • pp.189-237
    • /
    • 2013
  • Since central governments began to establish and use the Standard Records Management System(RMS) in 2007, more and more local governments and other public organizations have constructed RMS. RMS is the essential tool for records management in electronic environments, but it is not known how well the functions of RMS reflect standards and practice related records management or how many records managers use RMS in performing their works. This paper deals with analyzing the evaluation of 'classification & disposal schedule management' function in RMS. 'Classification & disposal schedule management' function has 4 subfunctions of review of classification & preservation period, management of the schedule items, assignment of classification scheme and reclassification. Classification and disposal schedule is at the heart of intellectual control of records and core area of records management. So it is important to analyze whether this function plays well a role in RMS or not. This research carried out evaluation of function and use about classification & disposal schedule management in RMS. Functional evaluation is to compare and analyze how well RMS meets the functional requirements which home and foreign standards give. Use evaluation is to investigate how records managers use RMS in accomplishing their task of managing classification & disposal schedule and to look into what is the problem with the use. This paper could get the implications through the survey of records managers who are working at central governments, regional local governments and basic local governments. And these implications are considered in institutional, functional, use and administrative aspect. It is important to communicate with stakeholders so that 'classification & disposal schedule management' function, further, all functions of the RMS in practice of records management could be used smoothly. Users of RMS have to raise demands or call for technical solutions of the problems which come up in use, while RMS developers and administrators must make more of an effort to satisfy their demands, reflect them on the RMS and enhance the system.

A Recidivism Prediction Model Based on XGBoost Considering Asymmetric Error Costs (비대칭 오류 비용을 고려한 XGBoost 기반 재범 예측 모델)

  • Won, Ha-Ram;Shim, Jae-Seung;Ahn, Hyunchul
    • Journal of Intelligence and Information Systems
    • /
    • v.25 no.1
    • /
    • pp.127-137
    • /
    • 2019
  • Recidivism prediction has been a subject of constant research by experts since the early 1970s. But it has become more important as committed crimes by recidivist steadily increase. Especially, in the 1990s, after the US and Canada adopted the 'Recidivism Risk Assessment Report' as a decisive criterion during trial and parole screening, research on recidivism prediction became more active. And in the same period, empirical studies on 'Recidivism Factors' were started even at Korea. Even though most recidivism prediction studies have so far focused on factors of recidivism or the accuracy of recidivism prediction, it is important to minimize the prediction misclassification cost, because recidivism prediction has an asymmetric error cost structure. In general, the cost of misrecognizing people who do not cause recidivism to cause recidivism is lower than the cost of incorrectly classifying people who would cause recidivism. Because the former increases only the additional monitoring costs, while the latter increases the amount of social, and economic costs. Therefore, in this paper, we propose an XGBoost(eXtream Gradient Boosting; XGB) based recidivism prediction model considering asymmetric error cost. In the first step of the model, XGB, being recognized as high performance ensemble method in the field of data mining, was applied. And the results of XGB were compared with various prediction models such as LOGIT(logistic regression analysis), DT(decision trees), ANN(artificial neural networks), and SVM(support vector machines). In the next step, the threshold is optimized to minimize the total misclassification cost, which is the weighted average of FNE(False Negative Error) and FPE(False Positive Error). To verify the usefulness of the model, the model was applied to a real recidivism prediction dataset. As a result, it was confirmed that the XGB model not only showed better prediction accuracy than other prediction models but also reduced the cost of misclassification most effectively.

Incidence of Viral Diseases on Solanaceae Crops in Gangwon Province (강원지역 가지과 작물 바이러스 발생현황)

  • Won, Heon-Seop;Park, Dong-Kwon;Kwon, Soon-Bae;Jo, Sun-Ok;Kang, Sung-Hee;Lee, Jae-Hong;Hwang, Se-Jeong;Jeong, Tae-Sung;Kim, Mi-Kyeong;Choi, Hong-Soo;Hong, Dae-Ki
    • Research in Plant Disease
    • /
    • v.25 no.1
    • /
    • pp.22-28
    • /
    • 2019
  • This study researched the current occurrence status of viral diseases of solanaceous crops in the main production areas of Gangwon region, for four years from 2014 to 2018. From 2014 to 2018, in eight cities and counties including Chuncheon, CMV, BBWV2, PMMoV, TSWV, and PVY occurred in chilli peppers. In case of tomato, the research was performed in 2017 and 2018 while TSWV and TYLCV were verified in Chuncheon, Hoengseong, and Cheorwon. Especially, TYLCV occurred in Chuncheon region for the first time in 2017, which was verified in 2018. Lastly, the current occurrence status of viral diseases of bell peppers was researched in seven cities and counties like Gangneung, Hoengseong, and Cheorwon from 2015 to 2018. In the results, CMV, BBWV2, PMMoV, PepMoV, and TSWV were verified in bell peppers of Gangwon region. During the research period, there were no crops suspected or infected by BWYV, so that it is judged that there is no villiferous or infected aphid by this virus in Gangwon-do. Such results of this study could be used as the basic data for the stable production of crops through the early prevention of plant diseases occurring in the solanaceous crops of Gangwon region.

Estimation of freeze damage risk according to developmental stage of fruit flower buds in spring (봄철 과수 꽃눈 발육 수준에 따른 저온해 위험도 산정)

  • Kim, Jin-Hee;Kim, Dae-jun;Kim, Soo-ock;Yun, Eun-jeong;Ju, Okjung;Park, Jong Sun;Shin, Yong Soon
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.21 no.1
    • /
    • pp.55-64
    • /
    • 2019
  • The flowering seasons can be advanced due to climate change that would cause an abnormally warm winter. Such warm winter would increase the frequency of crop damages resulted from sudden occurrences of low temperature before and after the vegetative growth stages, e.g., the period from germination to flowering. The degree and pattern of freezing damage would differ by the development stage of each individual fruit tree even in an orchard. A critical temperature, e.g., killing temperature, has been used to predict freeze damage by low-temperature conditions under the assumption that such damage would be associated with the development stage of a fruit flower bud. However, it would be challenging to apply the critical temperature to a region where spatial variation in temperature would be considerably high. In the present study, a phenological model was used to estimate major bud development stages, which would be useful for prediction of regional risks for the freeze damages. We also derived a linear function to calculate a probabilistic freeze risk in spring, which can quantitatively evaluate the risk level based solely on forecasted weather data. We calculated the dates of freeze damage occurrences and spatial risk distribution according to main production areas by applying the spring freeze risk function to apple, peach, and pear crops in 2018. It was predicted that the most extensive low-temperature associated freeze damage could have occurred on April 8. It was also found that the risk function was useful to identify the main production areas where the greatest damage to a given crop could occur. These results suggest that the freezing damage associated with the occurrence of low-temperature events could decrease providing early warning for growers to respond abnormal weather conditions for their farm.

Receipt of Official Documents after the Status Change of the Office of Crown Properties in The Great Han Empire (대한제국기 내장원의 위상 변화와 공문서 접수)

  • Park, Sung-Joon
    • The Korean Journal of Archival Studies
    • /
    • no.36
    • /
    • pp.35-67
    • /
    • 2013
  • As the office of crown properties expanded to financial structure having jurisdiction over various nation's purse in the Great Han Empire, its official document form has been changed. Unlike the early days, they had used official paper stamped with the words 'the Office of Crown Properties' eliminating 'Department of the Royal Household'. Also, the title on stamp of government position changed to 'Recipient of the Official of Crown Properties'. As the office of crown properties expanded as a great financial structure, it has grown in stature as an independent structure, and it was reflected in official document form. Such change was shown in document distribution system. The recipient of report from each district was the First Lord of Department of the Royal Household until 1897; however, the recipients of reports were mostly the office of Crown Properties from 1899. The Office of Crown Properties could not issue an official order before Aug 1899, since then the Office of Crown Properties had issued official orders to each district. However, the Office of Crown Properties could not handle the document in an equal position to the central organization yet. However, from Sep. 1900, the Office of Crown Properties handle the document with district organizations in equal position to the central organization, and a records office had been established in the Office of Crown Properties. Also, the Office of Crown Properties had handled official documents as an independent organization getting out of belonging organization to the department of Royal Household. Since the records office was established in Sep. 1900, the Office of Crown Properties had written receipt book autonomously. Comparing the receipt books in 1901 to the receipt books in 1905 and 1906, receipt numbers had been appeared from the book in 1905 and the organization in charge of the documents was recorded on some documents. Since no receipt book was found in 1902~1904, it is unknown when receipt number had been started indicating on the book. Seeing that the receipt number on the book of 1905 matched with contents on the receipt stamp, the receipt number has started indicating from around July, 1902; the period the receipt stamp has been started to use. Unlike the receipt stamp, the department in charge was indicated on the receipt book. It is because that the Office of Crown Properties changed writing system. Instead of classifying divisions, the Office of Crown Properties recorded in a book by order to receive, provided serial number, and wrote the department on the bottom of receipt book to classify by department in charge. Since establishment of the records office in Sep. 1900, the Office of Crown Properties had confirmed the receipt of document by stamping 'receipt of the Office of Crown Properties' and made receipt books as the office had started handled documents independently. Also, the Office of Crown Properties changed its system integrating division and recording in one book from the intial system classifying the book by division then receipt number and department in charge were indicated on the book. Also, receipt system has stabilized by stamping the receipt date and number on the received document.

A Plan to Activate the Archive of Maeul Communities (마을공동체 아카이브 활성화 방안)

  • Sohn, Dong-you;Lee, Kyoung-juhn
    • The Korean Journal of Archival Studies
    • /
    • no.35
    • /
    • pp.161-206
    • /
    • 2013
  • 'Maeul' is a concept connoting a community. As a place where ordinary people's lives are planned and realized, Maeul is the foundation of their daily lives as well as a place where they work, rest and enjoy pastime activities. In Korea, however, most Maeul communities are dismantled while going though the modern period representing colonization and developmental dictatorship. Growth-oriented industrialization and urbanization turned into such adverse effects as individualization, a sense of loss and a sense of alienation. Recently, through innovations from below, Maeuls are restored, and through Maeul communities restored this way, every Maeul and many researchers carry out activities to build a healthy civil society. This study was conducted on such a background. For a healthy restoration of Maeul communities and a sustainable operation of those communities, it is necessary to establish archives where record the trace of Maeul members' daily lives and relations between those members. The archive of Maeul communities is a place that contains each Maeul's local characteristics as well as human relations as well. It is because this place can be space where Maeul members can record their history, communicate with each other and make a better future. The archive of Maeul communities can be made into various different models, which can be operated by reflecting the identity of a community such as main agents and characteristics, objectives and orientation of objects recorded. Rather than when Maeul communities exist as individuals, they can display more important functions and better effect when they form a network. Therefore, it is needed to provide various and creative methodologies different from the existing government-led record management. Not only on the form of archives, but also all over their functions, such as collection, arrangement, classification, evaluation, management and utilization, Maeul and Maeul residents' norms, orientation and realistic conditions should be thoroughly reflected. Starting from a chance to look back at individuals' lives, the archive of Maeul communities will be a new chapter to restore and build a healthy community in our society and overcome social contradictions from below. Moreover, the archive of Maeul communities has a great significance that it will broaden its prospect creatively with a new paradigm, not only mechanically turning the existing public sector-centered record management into a non-governmental sector.

A Study on the Reproducibility of 3D Shape Model of Garden Cultural Heritage using Photogrammetry with SNS Photographs - Focused on Soswaewon Garden, Damyang(Scenic Site No.40) - (SNS 사진과 사진측량을 이용한 정원유산의 3차원 형상 재현 가능성 연구 - 명승 제40호 담양 소쇄원(潭陽 瀟灑園)을 대상으로 -)

  • Kim, Choong-Sik;Lee, Sang-Ha
    • Journal of the Korean Institute of Traditional Landscape Architecture
    • /
    • v.36 no.4
    • /
    • pp.94-104
    • /
    • 2018
  • This study examined photogrammetric reconstruction techniques that can measure the original form of a cultural property utilizing photographs taken in the past. During the research process, photographs taken in the past as well as photograph on the internet of Soswaewon Garden in Damyang(scenic site 40) were collected and utilized. The landscaping structures of Maedae, Aiyangdan, Ogokmun Wall, and Yakjak and natural scenery Gwangseok, of which photographs can be taken from any 360 degree direction from a close distance or a far distance without any barriers in the way, were selected and tested for the possibility of reproducing three-dimensional shapes. The photography method of 151 landscape photographs (58.6%) from internet portal sites for the aforementioned five landscape subjects containing information on the date the photograph was taken, focal length, and exposure were analyzed. As a result of the analysis, it was revealed that the majority of the photographs tend to focus on important parts of each subject. In addition, we discovered that there are two or three photography methods that internet users preferred in regards to each landscape subject. For the purposes of the experiment, photographs in which a single scene consistently appears for each landscape subject and it was determined that there was a high level of preference related to the photography method were analyzed, and three-dimensional mesh shape model was produced with a photoscan program to analyze the reproducibility of three-dimensional shapes. Based on the results of the reproduction, it was relatively possible to reproduce three-dimensional shapes for artifacts such as Ogukmun wall, Maedae, and Aeyangdan, but it was impossible to reproduce three-dimensional images for natural scenery or an object that has similar texture such as Yakjak and Gwangseok. As a result of experimentation related to the reconstruction of three-dimensional shapes with the photographs taken on site using a photography method similar to that of the photographs selected as previously mentioned, there was success related to reproducing the three-dimensional shapes of Yakjak and Gwangseok, of which it was not possible to do so through the photographs that had been collected previously. In addition, through comparison of past and present images, it was possible to measure the exact sizes as well as discover any changes that have taken place. If past photographs taken by tourists or landscape architects of cultural properties can be obtained, the three-dimensional shapes from a particular period of time can be reproduced. If this technology becomes widespread, it will increase the level of accuracy and reliability in regards to measuring the past shapes of cultural landscape properties and examining any changes to the properties.