• 지질공학
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• 제19권4호
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• pp.433-439
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• 2009

압축패커장치는 지하수관정의 지표하부오염방지시설의 개선을 위하여 개발한 장치이다. 이 장치는 안전잠금장치의 해제와 케이싱의 압축조작이 단순하여 시공이 간편하고, $4.5\;kg/cm^2$의 내압성을 갖고 있어 지하수 누출이 없도록 수밀성을 갖추고 있으며, 단일케이싱을 설치하며 그라우팅을 위한 확공은 300 mm로 굴착 가능하므로 시공비를 절약할 수 있다. 압축패커의 재질은 실리콘 고무를 사용하여 신장율이 590%이고 Pb, Cd, 페놀 등의 유해성분이 기준치 이하거나 불검출되어 우수한 환경성을 가지고 있다. 또한 시공비가 기존의 그라우팅 공법의 35~62% 이하, 환경신기술 제 47호인 팽창 패커 공법의 87% 이하로 시공이 가능한 경제적인 방법이며, 지하수 수질보전등에 관한 규칙, 제주도 지하수개발 이용시설 설치 및 관리기준, 환경부와 농림수산식품부의 소규모수도시설 운영관리 방안 지침 등 관련 법령규정에 적합한 제품이다.

• Journal of Advanced Marine Engineering and Technology
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• 제16권5호
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• pp.97-110
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• 1992

Rape-seed oil has high viscosity and high rubber content like other vegetable oils. When crude rape-seed oil obtained by a general oil extraction process is used in a diesel engine, automization condition during injection is not good and a large amount of combustion product is doposited in a combustion chamber. The improvement of a diesel engine is required to use rape-seed oil as a diesel engine fuel. In this study, the physical and chemical properties and combustion characteristics of rape-seed oil were investigated. The auxiliary aid was developed to improve automization condition and the effect of the auxiliary injection aid on the performance of a diesel engine was determined. The results are as follows. 1) Oil content of rape-seed is 45%. The exraction rate is 33%. The resuls show higher values compared to those of other vegetable oils. 2) The viscosity of rape-seed oil is 50.8 cSt and nearly 14 times of diesel oil viscosity. 3) The heating value and flash point of rape-seed oil are 9720kcal/Kg and 318$^{\circ}C$, respectively. 4) In case rape-seed oil is used as fuel, brake horse power, specific fuel consumption and brake thermal efficiency are compared to those of diesel oil. The results of rape-seed oil show 3.6%, 12.7% and 3.1% higher values. 5) Particle size of injection fuel with the auxiliary injection aid on the performance of a diesel engine was determined. The results are as follows. 1) Oil content of rape-seed is 45%. The extraction rate is 33%. The results show higher values compared to those of other vegetable oils. 2) The viscosity of rape-seed oil is 50.8 cSt and nearly 14 times of diesel oil viscosity. 3) The heating value and flash point of rape-seed oil are 9720kcal/Kg and 318.deg.C, respectively. 4) In case rape-seed oil is used as fuel, brake horse power, specific fuel consumption and brake thermal efficiency are compared to theose of diesel oil. The results of rape-seed oil show 3.6%, 12.7% and 3.1% higher values. 5) Particle size of injection fuel with the auxiliary injection aids is 100.mu.m smaller than that od injection fuel without the aid. 6) Brake horse power and brake thermal efficiency with the auxiliary injection aid increase 5.07% and 6.07%, respectively. However, specific fuel consumption decreases 3.85% with the auxiliary injection aid.

• 산학경영연구
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• 제11권
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• pp.277-293
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• 1998

연구의 목적은 종래 연구 발표된 대다수의 논문이 광고선전비와 매출액, 경영성과 간의 관계와 특정제품에 대하여 3년에서 5년간의 자료에 의하여 단편적 소표본적으로 분석한 문제를 완화하기 위하여 광고선전비가 영업성과 요소중 매출액, 영업이익의 상관관계를 분석하고자 하는데 있다. 본 연구의 목적을 수행하기 위하여 광고선전비증가율를 독립변수로 하고 경영성과를 나타내는 배출액증가율, 영업이익증가율을 종속변수로 하여 1981년부터 1996년까지(16년간) 생존한 제조기업을 중심으로 한국증권거래소에 계속 상장되어 있는 상장기업을 4개의 산업군, 즉 1) 음 식료품 산업, 2) 섬유 의복 가죽 산업, 3) 의약품 화학 석유 석탄 고무산업, 4) 조립금속 기계 장비산업 등으로 나누어 30 - 40개씩 125개 기업을 한국신용평가(주)의 KIS-DATA에서 무작위 추출하여 회귀분석 및 통계모형을 이용하여 각 변수사이에 상관관계가 있는지의 여부를 검정하였다. 이상과 같은 방법으로 연구분석한 결과 광고선전비의 크기가 기업의 경영성과에 영향을 미치는 것으로 나타났으나 업종별로는 섬유 의복 가죽 산업은 매출액증가율에만 유의적으로 나타났으며 시차분석에서는 음식료 산업의 경우에 만 매출액증가율이 부(-)의 유의적 관계가 있는 것으로 나타났고 그 이외산업 에서는 비유의적으로 나타났다. 또한 경제성장율과의 관계에서는 경제성장율이 낮을때 유의적으로 나타났다.

• Elastomers and Composites
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• 제46권1호
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• pp.37-44
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• 2011

Adipic acid(AA)와 diethylene glycol(DEG) 사이에서 일어나는 반응의 속도에 대한 유기나노점토(Cloisite 30B)의 영향을 규명하기 위하여 383K와 423 K에서 Br${\phi}$nsted acid인 p-toluene sulfonic acid(p-TSA)와 Lewis acid인 butylchlorotin dihydroxide를 촉매로 사용하여 에스테르 반응을 수행하였다. 촉매의 양은 전체반응물의 0.14 mol%만큼 사용하였다. 반응 생성물의 산가로부터 계산된 전환율 vs. 시간의 자료를 사용하여 반응속도를 해석하였다. [OH]/[COOH] 초기 몰비가 2인 상태에서 수행되는 polyester-diol 합성반응의 속도는 p-TSA 촉매하에서는 AA에 대하여 2차 반응으로, butylchlorotin dihydroxide 촉매하에서는 AA에 대하여 1차 반응으로 잘 해석되었으며 두 반응의 활성화 에너지는 각각 42.2 kJ/mol, 63.8 kJ/mol이었다. AA와 DEG에 Cloisite 30B를 5 wt% 첨가시키면 p-TSA 촉매는 활성이 크게 줄어 반응속도가 매우 느려졌으며, 이 때 활성화 에너지는 72.9 kJ/mol로 높게 계산되었다. Butylchlorotin dihydroxide 촉매는 Cloisite 30B의 첨가에 관계없이 거의 일정한 활성을 유지하였다. Butylchlorotin dihydroxide 촉매하에서 Cloisite 30B를 첨가한 반응의 활성화 에너지는 61.8 kJ/mol로 Cloisite 30B를 첨가하지 않은 반응의 활성화 에너지보다 약간 낮았다.

• Elastomers and Composites
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• 제47권4호
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• pp.336-340
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• 2012

사출성형품에서 잔류응력은 성형공정 중 열과 전단응력에 의해 형성된다. 잔류응력을 평가하는 방법은 여러 가지가 있는데, 불투명한 제품에서의 잔류응력은 케미칼 크랙킹 테스트 방법으로 측정 할 수 있다. 이 방법은 시편과 솔벤트가 반응하게 하여 측정하는 방법이다. 크랙은 응력의 크기에 따라 형성되기 때문에 크랙의 크기나 수를 측정하여 응력을 정량적으로 측정한다. 본 연구에서는 케미칼 크랙킹 방법으로 잔류응력을 측정하기 위한 기초자료인 응력과 크랙과의 관계를 규명하기 위한 실험을 수행하였다. 시편을 제작하기 위한 재료는 PC/PBT와 PC/ABS사용하였으며 지그를 이용하여 시편을 변형을 주고 이를 솔벤트에 담궈서 크랙을 유도하였다. 솔벤트는 tetrahydrofuran과 methyl alchol을 이용하여 제조하였다. 두 재료 모두 응력이 어느 정도 이상에서만 크랙이 형성되었으며, 크랙은 응력이 증가함에 따라 대략 2차함수로 증가하였다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 추계학술대회
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• pp.44-63
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• 2000

Situated close to Heathrow Airport, and adjacent to the M4 and M25 Motorways, the site at Axis Park is considered a prime location for business in the UK. In consequnce two of the UK's major property development companies, MEPC and Redrew Homes sought the expertise of Intergeo to remediate the contaminated former industrial site prior to its development. Industrial use of the twenty-six hectare site, started in 1936, when Hawker Aircraft commence aircraft manufacture. In 1963 the Firestone Tyre and Rubber Company purchased part of the site. Ford commenced vehicle production at the site in the mid-1970's and production was continued by Iveco Ford from 1986 to the plant's decommissioning in 1997. Geologically the site is underlain by sand and gravel, deposited in prehistory by the River Thames, with London Clay at around 6m depth. The level of groundwater fluctuates seasonally at around 2.5m depth, moving slowly southwest towards local streams and watercourses. A phased investigation of the site was undertaken, which culminated in the extensive site investigation undertaken by Intergeo in 1998. In total 50 boreholes, 90 probeholes and 60 trial pits were used to investigate the site and around 4000 solid and 1300 liquid samples were tested in the laboratory for chemical substances. The investigations identified total petroleum hydrocarbons in the soil up to 25, 000mg/kg. Diesel oil, with some lubricating oil were the main components. Volatile organic compounds were identified in the groundwater in excess of 10mg/l. Specific substances included trichloromethane, trichloromethane and tetrachloroethene. Both the oil and volatile compounds were widely spread across the site, The specific substances identified could be traced back to industrial processes used at one or other dates in the sites history Slightly elevated levels of toxic metals and polycyclic aromatic hydrocarbons were also identified locally. Prior to remediation of the site and throughout its progress, extensive liaison with the regulatory authorities and the client's professional representatives was required. In addition to meetings, numerous technical documents detailing methods and health and safety issues were required in order to comply with UK environmental and safety legislation. After initially considering a range of options to undertake remediation, the following three main techniques were selected: ex-situ bioremediation of hydrocarbon contaminated soils, skimming of free floating hydrocarbon product from the water surface at wells and excavations and air stripping of volatile organic compounds from groundwater recovered from wells. The achievements were as follows: 1) 350, 000m3 of soil was excavated and 112, 000m3 of sand and gravel was processed to remove gravel and cobble sized particles; 2) 53, 000m3 of hydrocarbon contaminated soil was bioremediated in windrows ; 3) 7000m3 of groundwater was processed by skimming to remove free floating Product; 4) 196, 000m3 of groundwater was Processed by air stripping to remove volatile organic compounds. Only 1000m3 of soil left the site for disposal in licensed waste facilities Given the costs of disposal in the UK, the selected methods represented a considerable cost saving to the Clients. All other soil was engineered back into the ground to a precise geotechnical specification. The following objective levels were achieved across the site 1) By a Risk Based Corrective Action (RBCA) methodology it was demonstrated that soil with less that 1000mg/kg total petroleum hydrocarbons did not pose a hazard to health or water resources and therefore, could remain insitu; 2) Soils destined for the residential areas of the site were remediated to 250mg/kg total petroleum hydrocarbons; in the industrial areas 500mg/kg was proven acceptable. 3) Hydrocarbons in groundwater were remediated to below the Dutch Intervegtion Level of 0.6mg/1; 4) Volatile organic compounds/BTEX group substances were reduced to below the Dutch Intervention Levels; 5) Polycyclic aromatic hydrocarbons and metals were below Inter-departmental Committee for the Redevelopment of Contaminated Land guideline levels for intended enduse. In order to verify the qualify of the work 1500 chemical test results were submitted for the purpose of validation. Quality assurance checks were undertaken by independent consultants and at an independent laboratory selected by Intergeo. Long term monitoring of water quality was undertaken for a period of one year after remediation work had been completed. Both the regulatory authorities and Clients representatives endorsed the quality of remediation now completed at the site. Subsequent to completion of the remediation work Redrew Homes constructed a prestige housing development. The properties at "Belvedere Place" retailed at premium prices. On the MEPC site the Post Office, amongst others, has located a major sorting office for the London area. Exceptionally high standards of remediation, control and documentation were a requirement for the work undertaken here.aken here.