• Title/Summary/Keyword: successor

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Review on the succession process of Pinus densiflora forests in South Korea: progressive and disturbance-driven succession

  • Choung, Yeonsook;Lee, Jongsung;Cho, Soyeon;Noh, Jaesang
    • Journal of Ecology and Environment
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    • v.44 no.3
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    • pp.126-142
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    • 2020
  • Background: Most of the Pinus densiflora forests, occupying the largest area, have been restored in South Korea since the 1970s. As young pioneer forests, the succession process is under way. Since the forests are distributed nationwide and are vulnerable to disturbances, the process may differ depending on the geography and/or site conditions. Therefore, we reviewed the direction, the seral communities, and the late-successional species of progressive and disturbance-driven succession nationwide in the cool-temperate zone through meta-analysis and empirical observations. Main text: As a result of a meta-analysis of the direct succession and vertical structure, we found that the P. densiflora forest is in a directionally progressive succession, changing to the broadleaved forest after forming a mixed forest with its overwhelming successor, Quercus species (particularly Q. mongolica and Q. serrata). In dry stands in a relative sense, the Quercus species was favored occupying over 80% of the abundance of the succeeding species. Therefore, in dry stands, it is presumed that Quercus-dominated stage would last for a long time due to the current dominance and long life span, and eventually, it settles as Quercus-broadleaved forest with a site change. Contrary to this, it is presumed that in mesic stands where Quercus species do not occur or have low abundance, the late-successional broadleaved species settle early to form a co-dominant forest with multiple species. Due to geographical limits, the species composition of the two late-successional forests is different. Disturbances such as insect pests and fire retrogressed vulnerable P. densiflora forest for a while. However, it was mostly restored to the Quercus forest and is expected to be incorporated in the pathway of the dry stand. Conclusions: We revealed the succession process of P. densiflora forests according to geography and moisture and found that stand moisture had a decisive effect on the species and abundance of the successor. Although the P. densiflora forest is undergoing structural changes, the forest is still young; so within a few decades, physiognomy is not likely to change. Therefore, the decrease in the forest area may be due to other causes such as disturbances and forest conversion rather than due to succession.

SURGICAL APPROACH TO THE INFRAOCCLUDED TEETH BY USING SPACE REGAINING TREATMENT (저위교합 유구치에서의 공간확장술을 이용한 외과적 접근)

  • Bang, Seok-Yun;Kim, Eun-Jung;Kim, Hyun-Jung;Kim, Young-Jin;Nam, Soon-Hyeun
    • Journal of the korean academy of Pediatric Dentistry
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    • v.32 no.3
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    • pp.531-536
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    • 2005
  • Infraclusion may be defined as teeth that stop their relative occlusal movement in the dental arches during or after the period of active eruption and then remain under the occlusal plane. Delayed exfoliation, malocclusion, increased susceptibility to dental caries and periodontal disease of both the neighboring teeth and retained molar, and dislocation of the successor are the consequencces of infraclusion of primary molars. Therefore, early diagnosis and appropriate treatments are necessary. The therapeutic approach of the infracluded teeth varied from preservation to extraction. The teeth with simple infraclusion without any signs of interference with occlusal and jaw development may be examined periodically with follow-up check and radiographically. However, if the infracluded tooth interferes with normal eruption of successor or shows any sign of delayed resorption, or the tipping of adjacent teeth or supraeruption of opposing teeth is expected, the teeth inflicted should be extracted and appropriate measures should be provided in order to maintain the normal development of occlusion and dentition. The adjacent teeth which have been collapsed over a infracluded deciduous teeth can disturb the arch length perimeter. In such cases, surgical approach might be necessary, although it would be difficult when teeth are severly leaned. However, an easier surgical access have been obtained by space regaining procedures, in young patients whose arch length has been shortened due to the infracluded teeth.

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Evaluating SR-Based Reinforcement Learning Algorithm Under the Highly Uncertain Decision Task (불확실성이 높은 의사결정 환경에서 SR 기반 강화학습 알고리즘의 성능 분석)

  • Kim, So Hyeon;Lee, Jee Hang
    • KIPS Transactions on Software and Data Engineering
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    • v.11 no.8
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    • pp.331-338
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    • 2022
  • Successor representation (SR) is a model of human reinforcement learning (RL) mimicking the underlying mechanism of hippocampal cells constructing cognitive maps. SR utilizes these learned features to adaptively respond to the frequent reward changes. In this paper, we evaluated the performance of SR under the context where changes in latent variables of environments trigger the reward structure changes. For a benchmark test, we adopted SR-Dyna, an integration of SR into goal-driven Dyna RL algorithm in the 2-stage Markov Decision Task (MDT) in which we can intentionally manipulate the latent variables - state transition uncertainty and goal-condition. To precisely investigate the characteristics of SR, we conducted the experiments while controlling each latent variable that affects the changes in reward structure. Evaluation results showed that SR-Dyna could learn to respond to the reward changes in relation to the changes in latent variables, but could not learn rapidly in that situation. This brings about the necessity to build more robust RL models that can rapidly learn to respond to the frequent changes in the environment in which latent variables and reward structure change at the same time.

Survey Research Regarding the characteristic of the Retirement House in Mountain Village of Shikoku - Focusing on Ochiai area in Higashiiyayama-son in Tokushima Prefecture of Japan (사국(四國)산촌의 은거옥(隱居屋)의 특성에 관한 조사연구 -일본 덕도현(德島縣) 동조곡산촌(東祖谷山村) 낙합지구(落合地區)를 중심으로-)

  • Park Chan
    • Journal of the Korean housing association
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    • v.17 no.4
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    • pp.57-64
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    • 2006
  • This research is the survey result of the retirement house in Ochiai area that is a famous as mountain village of Japan. This area is being formed in a steep slope and be arranged the building long a side along the contour line. As for the plan type of a main house 'the middle bedroom three-madori(bay) type' and 'the parallel two madori(bay) type' occupy many. As for in the retirement custom of Ochiai area the independence family style (separation/ separate meal/separate household economy) is a principle and a parents family builds the retirement house and move out. The plan. of the retirement house is two-room type of 'Omote(public room) and Uchi(kitchen and living room)' and agree with the plane prototype 'plan constitution of a necessary minimum' of farmhouse of this area. The reconstruction that the retirement house is remodeled handily with a main home, especially intend the convenience of the life such as a kitchen and toilet has been done. The retirement custom has been succeeded thoroughly until recent years in this area. However, this traditional custom is seeing the end, without there is the successor of a main house with depopulation.

The Acquisition Methodology Study of User Trace Data in Mac OS X (Mac OS X 운영체제상의 사용자 흔적정보 수집방안 연구)

  • Choi, Joon-Ho;Lee, Sang-Jin
    • The KIPS Transactions:PartC
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    • v.17C no.4
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    • pp.335-346
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    • 2010
  • Mac OS X is the Computer Operating System that develop in Apple Inc. Mac OS X is the successor to Mac OS 9 Version which had been Apple's primary operating system since 1984. Recently, Mac OS X 10.6 (Snow Leopard) has been manufactured and is distributed to user. Apple's Mac OS X Operating System is occupying about 10% in the world Operating System market share. But, Forensic tools that is utilized on digital forensic investigation can not forensic analysis about Mac OS X properly. To do forensic investigation about Mac OS X, information connected with user's action and trace can become important digital evidence in Operating System. This paper presents way about user trace data acquisition methodology in Mac OS X.

A study on the Ship Mortgages in English Law (영국법상 선박 모게지 (Mortgages) 에 관한 연구)

  • Jeong, Seon-Cheol
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2007.12a
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    • pp.58-59
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    • 2007
  • The English law of ship mortgages is successor to a very long tradition. From the earliest times loans have been required to finance maritime commerce. The term "ship" describes any kind of vessel used in navigation, while the term "ship mortgage" described a method of secured financing, under which a borrower transferred its interest in ship or other property to a creditor, to secure the payment of the debt owed by the borrower or the performance of some their obligation. The shipowner (the borrower)is known as the 'mortgagor, and the person lending the money is known as the 'mortgagee'.

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Study on Tongseol in "Hwangjenaegyeong(黃帝內經)" ($\ll$황제내경(黄帝内经)$\gg$ "통설(洞泄)" 약탐(略探))

  • Zhu, Peng-Ju;Chen, Shi-Yu;Gu, Feng
    • Journal of Korean Medical classics
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    • v.22 no.4
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    • pp.33-37
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    • 2009
  • According to the original texts in "Hwangjenaegyeong(黃帝內經)", it's considered that the Chinese character Tong(洞) in the word of Tongseol(洞泄) should be understood as fast[疾] or rapid[速],and the main symptom of Tongseol should be diarrhea of indigested food soon after a meal. Through comparing Tongseol with Dongpung(迵風) in Historical Records, we can draw the conclusions as following. Firstly, the ancient physicians attached great importance to the role of wind in the pathogenesis of diarrhea. Secondly, perhaps the ancient physicians had these ideas of "wind is rapid" and "strong wind can bring shaken" as well as "wind is related to the liver closely" already in the early Western Han Dynasty. Thirdly, the rich materials about the relationship between wind and diarrhea in "Hwangjenaegyeong(黃帝內經)" should be considered as the successor to the excellent thinking of their predecessors.

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A Study on the Domestic Architecture of Vincenzo Scamozzi (빈첸초 스카모치(Vincenzo Scamozzi)의 주거건축에 관한 연구)

  • Lee, Eun-Jung;Hong, Seok-Joo
    • Journal of The Korean Digital Architecture Interior Association
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    • v.11 no.4
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    • pp.13-20
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    • 2011
  • Vincenzo Scamozzi as the successor of Palladio stands as a major accomplishment of the task of cleanup to the classicism in 16th century. In addition, unlike the trend seen over Palladian, he shows succession and change of Renaissance villa. "L'Idea dell' Archittectura Universale; The Idea of a Universal Architecture"(1615) is a book of Scamozz's representative. This book is represented his idea for a residential building. His concepts for a residential building were analyzed through the analysis of his book and work. Scamozzi thought that domestic architecture should be designed according to he owner's social status and reputation. These concepts as decorum and this is divided into three categories. This is a threefold order, the first category and highest encompassing reigning princess and their families, who were more or less regarded as God's representatives on earth. The second category comprised noblemen and high office holders whose houses were to be, in all respects, a degree less grand, costly and dignified than the prince's residence. The third category was made up of prominent citizens and wealthy merchants whose houses were to have only moderate commoner did not come into this classification at all. - the magnifiche, honorevoli, and commune style of speech.

On the primacy of auditory phonetics In tonological analysis and pitch description;In connection with the development of a new pitch scale (성조 분석과 음조 기술에서 청각음성학의 일차성;반자동 음조 청취 등급 분석기 개발과 관련하여)

  • Gim, Cha-Gyun
    • Proceedings of the KSPS conference
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    • 2007.05a
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    • pp.3-23
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    • 2007
  • King Sejong the Great, his students in Jip-hyeun-jeon school and Choe Sejin, their successor of the sixteenth century, indicated Middle Korean had three distinctive pitches, low, high, and rising (phyeong-, geo-, sang-sheong). Thanks to $Hun-min-jeng-{\emptyset}eum$ as well as its Annotation and side-dots literatures in fifteenth and sixteenth centuries, we can compare Middle Korean with Hamgyeong dialect, Gyeongsang dialect, and extant tone dialects with joint preservers of what was probably the tonal system of unitary mother Korean language. What is most remarkable about middle Korean phonetic work is its manifest superiority in conception and execution as anything produced in the present day linguistic scholarship. But at this stage in linguistics, prior to the technology and equipment needed for the scientific analysis of sound waves, auditory description was the only possible frame for an accurate and systematic classification. And auditory phonetics still remains fundamental in pitch description, even though modern acoustic categories may supplement and supersede auditory ones in tonological analysis. Auditory phonetics, however, has serious shortcoming that its theory and practice are too subject to be developed into the present century science. With joint researchers, I am developping a new pitch scale. It is a semiautomatic auditory grade pitch analysis program. The result of our labor will give a significant breakthrough to upgrade our component in linguistics.

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The Typology of Urban-Rural Migration and Its Implications (도시민의 귀촌행태 유형화와 시사점)

  • Lee, Min Soo;Park, Duk Byeong
    • Journal of Agricultural Extension & Community Development
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    • v.19 no.4
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    • pp.1137-1170
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    • 2012
  • The study aims to identify the typology of urban-rural migration and its implications. Factors analysis showed that the motivation of migration were economic, idyllic, family, escape of urban life, and farm succession. The most important variable was economic motivation. Cluster analysis also showed that enterprise seeker, small new business seeker, idyllic seeker, and farm successor, This study will be helpful for policy makers to understand urban-rural migration while practical and policy implications were discussed.