• Title/Summary/Keyword: Heave

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Soil Quality Assessment for Environmentally Sound Agriculture in the Mountainous Soils; Analysis of Sediment Data and Suggestion of Best Management Practices (산지에서의 환경보전형 농업을 위한 토양의 질 평가;유사자료의 분석과 최적영농방법의 제안)

  • Choi, Joong-Dae;Park, Ji-Sung;Kim, Jeong-Je;Yang, Jae-E;Jung, Yeong-Sang;Yun, Sei-Young
    • Korean Journal of Environmental Agriculture
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    • v.19 no.3
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    • pp.201-205
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    • 2000
  • Eleven runoff $plots(3{\times}15\;m)$ were built on a sloping field of a high plateau in Kangwon Province, Korea. The plots were treated with different tillage, residue covers and fertilizers, corn and potato were cultivated, and sediment discharge was measured from the plots for 3 years. Agricultural management practices were monitored around the plots to develop adequate best management practices. The least sediment occurred from the plots with no-till and 100% residue cover $(corn,\;0.1{\sim}2.2\;t/ha/year)$ and with contour tillage and vinyl sheet cover plots $(potato,\;0.1{\sim}0.2\;t/ha/year)$. The largest sediment was measured from the plots with up-and-down till and no cover ($11{\sim}33$ and $16{\sim}31\;t/ha/year$ from corn and potato plots, respectively). The type of organic and commercial fertilizers seemed not to affect sediment discharge. Sediment discharge from contour plots were largely dependent on the collapse of ridges due to the flush of water stored in furrows. The sediment discharge from contour corn and potato plots with no residue cover was $10{\sim}27$ and $16{\sim}24\;t/ha/year$, respectively. No-till with residue cover, vinyl cover for tuber crops, construction of furrow dam, frost heave research, furrow and ridge tillage with furrow dam after tuber crop harvest, limited stalk harvest of row crops, use of winter cover crops, and other common best management practices were recommended to minimize the sediment discharge from a high plateau sloping land culture.

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Effect of Bottom Hole Pressure and Depressurization Rate on Stability and Gas Productivity of Hydrate-bearing Sediments during Gas Production by Depressurization Method (감압법을 이용한 가스 생산 시 하이드레이트 부존 퇴적층의 지반 안정성 및 가스 생산성에 대한 시추 공저압 및 감압 속도의 영향)

  • Kim, Jung-Tae;Kang, Seok-Jun;Lee, Minhyeong;Cho, Gye-Chun
    • Journal of the Korean Geotechnical Society
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    • v.37 no.3
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    • pp.19-30
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    • 2021
  • The presence of the hydrate-bearing sediments in Ulleung Basin of South Korea has been confirmed from previous studies. Researches on gas production methods from the hydrate-bearing sediments have been conducted worldwide. As production mechanism is a complex phenomenon in which thermal, hydraulic, and mechanical phenomena occur simultaneously, it is difficult to accurately conduct the productivity and stability analysis of hydrate bearing sediments through lab-scale experiments. Thus, the importance of numerical analysis in evaluating gas productivity and stability of hydrate-bearing sediments has been emphasized. In this study, the numerical parametric analysis was conducted to investigate the effects of the bottom hole pressure and the depressurization rate on the gas productivity and stability of hydrate-bearing sediments during the depressurization method. The numerical analysis results confirmed that as the bottom hole pressure decreases, the productivity increases and the stability of sediments deteriorates. Meanwhile, it was shown that the depressurization rate did not largely affect the productivity and stability of the hydrate-bearing sediments. In addition, sensitivity analysis for gas productivity and stability of the sediments were conducted according to the depressurization rate in order to establish a production strategy that prevents sand production during gas production. As a result of the analysis, it was confirmed that controlling the depressurization rate from a low value to a high value is effective in securing the stability. Moreover, during gas production, the subsidence of sediments occurred near the production well, and ground heave occurred at the bottom of the production well due to the pressure gradient. From these results, it was concluded that both the productivity and stability analyses should be conducted in order to determine the bottom hole pressure when producing gas using the depressurization method. Additionally, the stress analysis of the production well, which is induced by the vertical displacements of sediments, should be evaluated.

The Value of Peace and the Modern Significance of Haewon Sangsaeng (해원상생사상의 평화적 가치와 현대적 의의)

  • Bae, Kyu-han
    • Journal of the Daesoon Academy of Sciences
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    • v.40
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    • pp.1-38
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    • 2022
  • The aim of this research is to discover the value of peace conveyed by Haewon Sangsaeng, the Resolution of Grievances for Mutual Beneficence, as espoused by Holy Teacher Kang Jeungsan (姜甑山, 1871~1909) and to evaluate its modern significance. To the faithful, Jeungsan is seen as the Supreme God who descended into the world in the Late Joseon Dynasty in the year 1871. Until the time of His passing away into Heaven in 1909, He vastly saved the world and fulfilled the hopes of humankind by carrying out the fundamentally innovative Reordering Works of Heaven and Earth (1901~1909) in the Three Realms of Heaven, Earth, and Humanity. He has thereby been appraised as a great religious figure within religious and academic circles. Jeungsan's ideological contributions can be summarized into two main points. One is the concept of 'the Great Opening and the Later World,' which foreshadowed the liquidation of the old system of order and the arrival of a new world. The other contribution is the concept of 'the Resolution of Grievances for Mutual Beneficence,' a fundamental principle meant to achieve human salvation and world peace. In this context, 'the Great Opening' is precisely a 'positivistic religious expression of peace,' and 'the Resolution of Grievances for Mutual Beneficence' is the principle by which 'peace can be achieved in the world for all humankind.' In particular, the Resolution of Grievances for Mutual Beneficence is a tenet within the doctrine of Daesoon Jinrihoe, and it is the main concept that forms the basis of Daesoon Thought. It can be said to be the core current that flows through Jeungsan's Reordering Works of Heaven and Earth. Nowadays, the Resolution of Grievances for Mutual Beneficence is being discussed and cited in various ways in academic fields as well as in discourse on coexistence, mutual beneficence, and peace. The Resolution of Grievances for Mutual Beneficence is specifically based on observations of the structure of conflicts as observed throughout world history via global conflicts, regional conflicts, cultural conflicts, ideological conflicts, class conflicts, generational conflicts, racial conflicts, religious conflicts, and other such conflicts. That is why the Resolution of Grievances for Mutual Beneficence is discussed in depth within academic settings wherein the nature of conflict-resolution is examined. Looking at the previous studies on this topic, those studies tended to focus on key concepts or concerns such as human beings, divine beings, the earthly paradise of the Later World, ideal societies, world peace, new principles of order, and lasting peace. In particular, the Resolution of Grievances for Mutual Beneficence has been presented as directly related to concepts such as love, coexistence, harmony, and peace for humankind and the world. Its significance has been applied to ethics, philosophy, order, and principles, and it has been understood as conveying values such as peace. Accordingly, this paper examines the ideological connections to the succession and establishment of Jeungsan's notion of the Resolution of Grievances for Mutual Beneficence based on previous research, but further examines the value of peace communicated via the principles and ideas that pervade current discourse on the Resolution of Grievances for Mutual Beneficence. I hope to thoroughly explore Haewon Sangsaeng in regards to its modern significance to the world and to humankind.