• Title/Summary/Keyword: Environments Changes

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Holocene sea-level rise and paleoenvironmental changes in Korea Strait shelf (대한해협 대륙붕 해역의 홀로세 해수면 상승과 고환경변화)

  • 남승일;장정해;공기수;김성필;유동근
    • The Korean Journal of Quaternary Research
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    • v.17 no.1
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    • pp.7-16
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    • 2003
  • A 31m-long sediment core (SSDP-102) was taken from the inner shelf (about 40m water-depth) off the northwestern coast of the Korea Strait. Detailed lithofacies and organic-geochemical analyses were performed to establish a high-resolution stratigraphy in the Korea Strait shelf and to reconstruct the paleoenvironmental changes associated with the Holocene marine transgression. The stratigraphic framework of the core was primarily established using 6 AMS $^{14}C$ ages. The sedimentary record of the core SSDP-102 allows for the reconstruction of the paleoenvironmental changes during the last 12.1 ka BP. According to the high-resolution seismic reflection profiles, lithofacies and organic-geochemical data, the core SSDP-102 can be divided into three units (III to I in ascending order) above the acoustic basement. The three units reflect distinct changes of depositional environments resulted from the post-glacial marine transgression. Therefore, it is suggested that three phases of sea-level change have occurred within the inner shelf of the Korea Strait following the Holocene marine transgression. (1) estuarine environments from ca. 12.1 to 6.2 ka BP; (2) near-shore environments with a period of decreased rising of sea level between 6.2 and 5.1 ka BP; (3) near-shore to modem marine environments after 5.1 ka BP. In particular, the present marine conditions influenced by the warm Tsushima Current have been gradually established after ca. 5.1 ka BP.

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A Study on the Role of Input Stabilization for Successful Settle down of TRM in Production Process : A Case of Display Industry (생산공정에서 TRM의 성공적 정착을 위한 Input 안정화의 역할에 관한 연구 : 디스플레이 산업 중심으로)

  • Cho, Myong Ho;Cho, Jin Hyung
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.39 no.1
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    • pp.140-152
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    • 2016
  • It is very important for the competitiveness and sustainable management of enterprises that the rapid changes in the managerial environments quickly and accurately are responded. For example, the large-scale investment accompanied by bad alternatives in accordance with misunderstanding of the managerial environments yields the huge cost and effort to modify and improve. In firm management, the quality of products and the productivity are influenced by changes of the endogenous factors yielded in manufacturing process and the exogenous factors as market, etc. These changes include not only changes in 4M (man, machine, material, method) but also those in the market, competitors, and technologies in the process of commodification, i.e., first, such disturbances make dispersion of the process big and odd. By Shewhart chart it can be checked that the process monitored is control-in or out. Business administration executes activities for input stabilization by monitoring changes in 4Ms, comparing with the standards, and taking measures for any abnormality. Second, TRM (technology road map) is to prospect product deployment and technological trend by predicting technologies in the competitive environment as the market, and to suggest the future directions of business. So, TRM must be modified and improved according to DR (design review) stages and changes in mass-production like input material change. Therefore, a role of TRM in input stabilization for reducing cost and man-hour is important. This study purposed to suggest that the environment changes are classified into endogenous factors and exogenous factors in production process, and then, quality and productivity should be stabilized efficiently through connection between TRM and input stabilization, and to prove that it is more effective for the display industry to connect TRM with input stabilization rather than to use TRM separately.

Directions for the Implementation of Agricultural Extension Services in an Age of Localization (지방직화이후 새로운 농촌지사업의 추진방향)

  • Yang, Seung-Choon;Choe, Young-Chan
    • Journal of Agricultural Extension & Community Development
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    • v.2 no.2
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    • pp.163-173
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    • 1995
  • Agricultural extension services in Korea has experienced various system changes and accomplishments. The biggest achievement of extension was rice self-suffiency in the 1970s and abundant vegetable and animal production in the 1980s. The emerging challenges of international competition and localization are contributing to significant changes such as the decentralization of activities and shared responsibilities between the central government and local governments. Change, while it threatens the status quo, is a challenge and an opportunity to review and revamp ensconced and often rigid structures. In this sense, it is time to start a new era in agricultural extension. The development of agricultural extension requires keen appraisals and cogent analysis based on the realities of each specific regional situation. In order to develop agricultural extension services, the various aspects, the synthetic identification of its environments, the clarification of the client, the program development, and the effective mechanisms between research and extension must be considered. Especially, agricultural extension systems should be flexible and adjust to changing environments and the farmers' needs.

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Robust Vision-Based Autonomous Navigation Against Environment Changes (환경 변화에 강인한 비전 기반 로봇 자율 주행)

  • Kim, Jungho;Kweon, In So
    • IEMEK Journal of Embedded Systems and Applications
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    • v.3 no.2
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    • pp.57-65
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    • 2008
  • Recently many researches on intelligent robots have been studied. An intelligent robot is capable of recognizing environments or objects to autonomously perform specific tasks using sensor readings. One of fundamental problems in vision-based robot applications is to recognize where it is and to decide safe path to perform autonomous navigation. However, previous approaches only consider well-organized environments that there is no moving object and environment changes. In this paper, we introduce a novel navigation strategy to handle occlusions caused by moving objects using various computer vision techniques. Experimental results demonstrate the capability to overcome such difficulties for autonomous navigation.

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An Empirical Investigation for EIS Utilization:On the Basis of TAM (중역정보 시스템의 활용에 관한 실증연구)

  • Kim, Jong-Weon
    • The Journal of Information Systems
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    • v.6 no.1
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    • pp.257-291
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    • 1997
  • Today, executives in the company operate their organizations under highly competitive environments with dynamic technological, economic, and political changes. Under these new environment changes, they play the important role in establishing the future directions and strategic orientations of organizations. In general, executive information systems (EIS) are designed to support these roles of executives. They can help executives access and use the information they require about the organization's internal and external environments. In spite of such potential EIS support for executives, only a limited number of empirical studies have been published in this area. by employing a well-established theory of computer usage behavior (Technology Acceptance Model : TAM), this study systematically investigates the key factors in the successful utilization of an EIS. The empirical results from this study may prove useful for both IS researchers and practitioners.

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Excavation and Building Damage Assessment - Fundamentals (지반굴착과 주변 구조물 손상평가 - 기본개념)

  • 유충식
    • Proceedings of the Korean Geotechical Society Conference
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    • 2002.03a
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    • pp.263-270
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    • 2002
  • During deep excavation, changes in the state of stress in the ground mass around the excavation and subsequent ground losses inevitably occur. These changes in the stress and ground losses are reflected on surrounding ground in the form of ground movements, which eventually Impose strains onto nearby structures through translation, rotation, distortion, and possibly damage. A substantial portion of the cost of deep excavations in urban environments is, therefore, devoted to prevent ground movements. Prediction of ground movements and assessment of the risk of damage to adjacent structures has become an essential part of the planning, design, and construction of a deep excavation project in the urban environments. This paper presents excavation-induced ground movement characteristics as well as important issues related to excavation-induced building damage assessment.

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Constructing the Functional Models of Wetland Biotopes - Focused on the Bangdong Wetland - (습지형 비오톱 기능모델 구성 - 방동소택지를 사례로 -)

  • Koo, Bon-Hak;Kim, Kwi-Gon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.2 no.2
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    • pp.1-8
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    • 1999
  • This study is one of the processes to build the artificial wetlands in the urban area. The purpose of this study was to survey biotic or physical environments, and to review modelling techniques to find out the ecological structure and function. Case study site was the Bangdong wetland in the north west side of Taejon metropolitan city. The number of species of insects decreased during monitoring. But the number of individuals of insects decreased abruptly after increasing. And then biodiversity index dropped and dominance index increased. So the structure of biotopes was affected by weather conditions. And in the restricted area such as urban area, the changes of insects were affected sensitively by not physical but environmental changes. As for birds, the number of species was reduced a little, but the number of individuals increased abruptly. And dominance index increased slowly. The changes of water depth and increase of temperature affected the habitat condition of vegetations and birds, so the dominance index of specific species increased. In urban areas it is necessary to continue management for water environmental changes, such as the depth and area of water. The number of species of fishes was reduced a little, but the number of individuals increased abruptly. And dominance index and biodiversity index decreased slowly. But the water environments was so changeable that it is difficult to explain current status as some specific trends. The number of species of reptiles and amphibians changed little, but the number of individuals increased abruptly. And dominance and biodiversity were not changed. The changes of water depth and temperature affected the habitat of every species the environmental changes affected.

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Adaptive Application Component Mapping for Parallel Computation Offloading in Variable Environments

  • Fan, Wenhao;Liu, Yuan'an;Tang, Bihua
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.11
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    • pp.4347-4366
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    • 2015
  • Distinguished with traditional strategies which offload an application's computation to a single server, parallel computation offloading can promote the performance by simultaneously delivering the computation to multiple computing resources around the mobile terminal. However, due to the variability of communication and computation environments, static application component multi-partitioning algorithms are difficult to maintain the optimality of their solutions in time-varying scenarios, whereas, over-frequent algorithm executions triggered by changes of environments may bring excessive algorithm costs. To this end, an adaptive application component mapping algorithm for parallel computation offloading in variable environments is proposed in this paper, which aims at minimizing computation costs and inter-resource communication costs. It can provide the terminal a suitable solution for the current environment with a low incremental algorithm cost. We represent the application component multi-partitioning problem as a graph mapping model, then convert it into a pathfinding problem. A genetic algorithm enhanced by an elite-based immigrants mechanism is designed to obtain the solution adaptively, which can dynamically adjust the precision of the solution and boost the searching speed as transmission and processing speeds change. Simulation results demonstrate that our algorithm can promote the performance efficiently, and it is superior to the traditional approaches under variable environments to a large extent.