• 제목/요약/키워드: Destruction

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Conservation of Biodiversity and Forest Resources in Nepal -Degradation and Threats-

  • Ghimire, Bimal Kumar;Islam, Mohammad Saiful;Chun, Su-Kyoung
    • 한국가구학회지
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    • 제19권4호
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    • pp.300-306
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    • 2008
  • Nepal is rich country in terms of its vast array of biological diversity. The relationship between local communities and the biological diversity in Nepal is a very entangle one, whereby two-thirds of our population are heavily dependent upon the biodiversity for their survival. The destruction of biodiversity signifies the destruction of people's livelihoods and survival. Biodiversity and genetic resources conservation has been a most significant part of the Nepalese society due to its socio-economic and cultural importance and provides the human race trees for timber, fuel, food, industrial raw materials, pharmaceuticals, beverages and environmental stabilization. Threats to biodiversity at global level is of greater concern, specially, human activities are the greatest factor currently affecting biodiversity, through the use of natural resources by industry, agriculture, hunting, and energy generation.

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재생굵은골재를 사용한 초유동 콘크리트의 강도 및 비파괴 특성 (Strengths and Non-destruction Properties of Super Flow Concrete Using Recycled Coarse Aggregate)

  • 성찬용
    • 한국농공학회논문집
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    • 제47권1호
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    • pp.25-32
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    • 2005
  • This study was performed to evaluate strengths and non-destruction properties of super flow concrete using recycled coarse aggregate. At the curing age of 28 days, the compressive strength was 22.7-37.5 MPa, the splitting tensile strength was $2.65\~3.73$ MPa, the flexural strength was $5.78\~6.86$ MPa, the ultrasonic pulse velocity was $3,103\~3,480$ mis, the dynamic modulus of elasticity was $3.401{\times}104\~4.521{\times}104$MPa, respectively. The strengths, ultrasonic pulse velocity and dynamic modulus of elasticity of super flow concrete were decreased with increasing the content of recycled coarse aggregate. The super flow concretes using recycled coarse aggregate were improved by substitution in the range of less than the fly ash content 30010 and recycled coarse aggregate content $75\%$.

Regeneration of Spent Carbon by a Novel Oxidative Thermal Process

  • 류건상;Shybender Kapila
    • Bulletin of the Korean Chemical Society
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    • 제18권8호
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    • pp.811-814
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    • 1997
  • An oxidative thermal regeneration process was developed and evaluated for its potential applicability in several environmental areas. The feasibility of the process is affected strongly by the gradual carbon loss, energy consumption, physical changes of carbon, and effective destruction efficiency of adsorbed materials during the regeneration. The aim of the study is to determine the optimum conditions to maintain acceptable destruction efficiency for adsorbed organics, controlling oxidant flow rate. Prior to its applications, various preliminary tests were carried out to determine the effects of experimental parameters on the process. The tests performed were reaction temperature, carbon loss, surface area, surface structure, and adsorptive property. The results of these tests show that the parameters are dependent on oxidant flow rate, and suggest that the process is comparable and, in some ways, possibly superior to conventional regeneration techniques because the oxidative process is a single step and less energy intensive.

Application of a Novel Carbon Regeneration Process for Disposal of APEG Treatment Waste

  • 류건상;Shubender Kapila
    • Bulletin of the Korean Chemical Society
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    • 제18권8호
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    • pp.814-818
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    • 1997
  • The chemical waste treatment, APEG (alkali/polyethylene glycol) process has been shown to be effective for the dechlorination of PCBs in transformer oil. Considerable amount of PCBs, however, still remains in the waste exceeding the 25-50 ppm limit set by regulatory agency. A new thermal regeneration technology has been developed in our laboratory for disposal of hazardous organic wastes. Due to the limited oxidation of carbon surface through the reverse movement of flame front to oxidant flow, this technology was termed counterflow oxidative system (COS). Specially, the oxidant flow in the COS process is a principal parameter which determines the optimum conditions regarding acceptable removal and destruction efficiency of adsorbed organic wastes at minimal carbon loss. The COS process, under optimum conditions, was found to be very effective and the removal and destruction efficiency of 99.99% or better was obtained for residual PCBs in the waste while bulk (≥90%) of carbon was recovered. Any toxic formation of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzo furans (PCDFs) were not detected in the regenerated carbon and impinger traps. The results of surface area measurement showed that the adsorptive property of regenerated carbon is mostly reclaimed during the COS process.

Reconstructive rhinoplasty with costal cartilage grafting: A case report of relapsing polychondritis

  • Lee, Yunhae;Choi, Hyungon
    • 대한두개안면성형외과학회지
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    • 제20권5호
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    • pp.341-344
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    • 2019
  • Relapsing polychondritis (RP) is a rare autoimmune disorder of unknown etiology characterized by recurrent episodes of inflammation and the destruction of cartilaginous tissues, primarily involving the ear, nose, and the respiratory tract. Nasal chondritis is present in 24% of patients at the time of diagnosis and develops subsequently in 53% throughout the diseases progress. Progressive destruction of nasal cartilage leads to the characteristic flattening of the nasal bridge, resulting in the saddle nose deformity. In patients with RP, surgical management for saddle nose is carefully decided due to the disease relapsing characteristics. We present a RP patient with a saddle nose deformity who underwent reconstruction rhinoplasty with autologous costal cartilage grafting. At 6-month follow-up, the patient retained good esthetic results and showed neither complication nor relapse of RP.

Changes in Dogs' Social Behavior Toward Humans

  • Kang, Ok-Deuk
    • 한국환경과학회지
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    • 제31권3호
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    • pp.237-245
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    • 2022
  • The purpose of this study is to evaluate dogs' sociality toward human strangers in the absence of an owner by analyzing changes in dogs' behavior during a task of making eye contact with an experimenter to obtain snacks. A total of 17 dogs were divided into groups of high sociality (HS; n = 10, 4.4 ± 3.87 years) and low-sociality (LS; n = 7, 3.71 ± 2.06 years). A comparison of the average frequency of five behavioral types-fear-appeasement behaviors (P<0.001), sociability-related behaviors (P<0.001), stress-related behaviors (P<0.05), destruction (P < 0.001), and vocalization (P < 0.001)-between the groups showed a significant difference in all five categories. Together, these results suggest that dogs with high sociality are less exposed to various stresses and have a higher ability to adapt to new environments than dogs with low sociality. This can predict dogs' adaptability to a new environment and positive outcomes in their daily life with the owner.