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전기자동차 개발

  • 임성기
    • 전기의세계
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    • v.41 no.12
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    • pp.21-30
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    • 1992
  • 내연기관의 가솔린자동차보다 역사가 오래된 전기자동차는 상대적으로 주생성능과 가격 경쟁력의 열세로 그 자취를 감추었고 최근까지 주로 특수목적의 단거리 저속차량으로 사용되고 있다. 그러나 1890년대 후반부터 전세계가 자동차배기가스에 의한 대기오염과 지구온난화 현상등의 문제를 심각하게 공감하게 되었고 마침내 미국 캘리포니아주에서는 전가자동차의 강제판매를 규정화하게 이르렀다. 이 규정에 의하면 1998년도부터 차량 판매대수의 2%를 전기자동차 판매로 강제요구하고 있다. 이 비율은 2000녀도에 5% 2003년에는 10%로 늘어날 계획이다. 따라서 미국에 많은 자동차를 수출하고 있는 일본, 독일 및 여러 유럽국가에서는 이 사업에 막대한 자금을 투자하며 개발에 몰두하고 있다. 미국의 Big3도 에너지성의 도움으로 최근 USABC를 결성하여 전기자동차 개발에 박차를 가하고 있다. 지금까지 기존의 가솔린자동차 기술에 있어서 일본과 독일에 상대적 열세에 있었던 미국도 이번 캘리포니아주의 전기자동차 강제판매 규정에 따른 전기자동차 사업으로 미국자동차 시장의 새로운 판도를 조성하겠다는 의도인듯하다. 국내에서도 정부가 이 사업의 중요성을 심각히 인식하고 G7사업과제의 하나로 선정하여 산, 학, 연 각층의 전문가가 참여하여 성공적으로 개발을 마칠 수 있도록 적극 지원하고 있다. 지금까지의 평균주행성능을 보면 최고속도 100-120km/h, 일층전 최대주행거리 150-200km 정도이며, 아직 양산체제에 돌입하지 않았기 때문에 가격면에서 경쟁력이 없는 실정이다. 그러나 1990년도에 들면서 각종 요소부품들의 기술수준이 급성장을 이루어서 앞으로 10년정도 후면 성능과 가격면에서 가솔린자동차와 대등한 수준의 전기자동차 개발이 실현될 수 있으리라 예측된다.는 영향받지 않았다. Clonidine의 심박수 감소작용은 .뇌실내및 정맥내 diltiazem이나 nifedipine 처리후에 감약되었다. 5). 뇌실내 clonidine$(30{\mu}g)$ 처 리후 뇌실내 diltiazem$(400{\mu}g)$과 nifedipine$(350{\mu}g)$의 혈압하강및 심박수 감소효과는 영향 받지 않고 그대로 나타났다. 이상의 결과로 diltiazem과 nifedipine은 가토뇌내에서 methoxamine에 의한 혈압상승의 작용점인 alrfia-1 adrenoceptor의 흥분에는 영향을 미치지 못하나 clonidine의 작용점인 alpha-2 adrenoceptor의 흥분에 의한 혈압하강및 심박수 감소효과는 억제한다고 추론하였다.thin 함량은 110.6 mg/L로서 산업적인 생산성이 있는 것으로 나타났다. 이번 연구를 통하여 개발된 변이주 B76 및 이의 대량 발효를 위한 최종조건의 정립은 향후 astaxanthin의 산업적 생산공정에 필요한 기초자료로 이용될 것으로 기대된다.색총말내에 소형의 도형, 소형의 장형 연접소포 및 DENSE CORE VESICLE의 3가지 연접소포를 가지고 있었고 출현빈도수는 촉각엽에서 가장 큰 33%이었다. 제5형 신경연접은 축색종말내에 중등도크기의 원형, 대형의 원형연접소포 및 DENSE CORE VESICLE을 포함하였고 13%의 출현빈도수로 관찰되었다. 배추횐나비의 촉각에 있는 지각신경세포가 뇌의 촉각엽으로 뻗어 들어가 위의 5가지 신경연접중 어느 형을 형성하는지를 관찰하기 위하여 좌측 촉각의 기부를 제거하여 지각신경세포를 절단하였는데 그 결과, 좌측 촉각엽에서 제4형의 신경연접이 퇴행성 변화를 나타내었다.

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A Study on the Effect of Sulfur Content in Fuel Oil on the Emission of Air Pollutants According to Operating Conditions of Small Ship Engines (선박용 소형 엔진에서 연료유 내 황 함유량이 운전 조건에 따라 대기오염물질 배출에 미치는 영향에 관한 연구)

  • Lee, Kyeong-yeol;Rho, Beom-seok;Lee, Won-Ju;Choi, Jae-hyuk
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.24 no.6
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    • pp.834-840
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    • 2018
  • In this study, the characteristics of air pollutant emissions from ships' engines have been investigated by conducting E2 and E3 cycle mode tests. A engine 360Ps (Doosan L126TIH engine) and 400kW dynamometer Horiba-Schenck were utilized for engine tests. The FTIR analyzer and SPC were used to measure exhaust gas (NOx, SOx etc.) and PM (particulate matter), respectively. The results showed that the emissions of THC and CO produced from engine were increased with the increase of sulfur content in fuel oils at E2 and E3 cycle modes. The kinetic viscosity of the fuel increased as the sulfur content of the fuel increased, thereby the specific fuel oil consumption (SFC) of the engine improved. This result is considered to be due to improved combustion conditions due to increased average diameters of sprayed particles and due to increased kinetic viscosity under constant fuel injection pressure in this study. In the case of NOx emission, this study showed no significant change in amount of sulfur content.

Study of Combustion Characteristics with Variations of Combustion Parameter in Ultra-Lean LPG Direct Injection Engine (연소제어인자의 변화에 따른 직접분사식 초희박 LPG엔진의 연소특성 연구)

  • Park, Yun Seo;Park, Cheol Woong;Oh, Seung Mook;Kim, Tae Young;Choi, Young;Lee, Yong Gyu
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.37 no.6
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    • pp.607-614
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    • 2013
  • Nowadays, automotive manufacturers have developed various technologies to improve fuel economy and reduce harmful emissions. The ultra-lean direct injection engine is a promising technology because it has the advantage of improving thermal efficiency through the deliberate control of fuel and ignition. This study aims to investigate the development of a spray-guided-type lean-burn LPG direct injection engine through the redesign of the combustion system. This engine uses a central-injection-type cylinder head in which the injector is installed adjacent to the spark plug. Fuel consumption and combustion stability were estimated depending on the ignition timing and injection timing at various air-fuel ratios. The optimal injection timing and ignition timing were based on the best fuel consumption and combustion stability.

A Study on the Analysis of Polycyclic Aromatic Hydrocarbons in Air (대기중 다환 방향족 탄화수소류의 분석에 관한 연구)

  • Pyo, Hee-Soo;Hong, Jee-Eon;Lee, Kang-Jin;Park, Song-Ja;Lee, Won
    • Analytical Science and Technology
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    • v.13 no.4
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    • pp.453-465
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    • 2000
  • Polycyclic aromatic hydrocarbons (PAHs) were produced by thermoreaction (incompletely combustion) of organic compounds such as fuel, gasoline, diesel etc, and were known the strong carcinogenic compounds. In our country, a study for health risk assessment of PAHs in air were needed according to rapidly increasing of motor vehicle and progressing to industrial country. In this study, concentrations of PAHs in 263 air samples of fourteen sites-Seoul, Pusan, etc-according to four times sampling for one year are measured by GC/MSD for basic research for health risk assessment. As the result, 14 PAHs are detected in all samples and annual average concentration of total PAHs was $28.72ng/m^3$ and highest average concentration of total PARs was $47.76ng/m^3$ in winter season. The concentrations of total PAHs are proportioned to amount of extracted organic material (EOM). The average concentration of total PAHs in EOM was 0.28%.

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단백질 수준에 따른 비태인의 급여가 산란계의 생산능력과 난품질, 혈액 성상에 미치는 영향

  • 류명선;박재홍;박성복;류경선
    • Proceedings of the Korea Society of Poultry Science Conference
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    • 2003.11a
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    • pp.91-92
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    • 2003
  • 비태인의 급여(0, 600 ppm)가 사료의 단백질 수준(14, 16 %)에 따라 산란계의 생산성과 난품질, 혈액성상, 간과 가슴육의 일반성분에 미치는 영향을 구명하기 위하여 83주령 하이라인 산란계 192수를 이용하여 12주간 사양실험을 실시하였다. 기초사료는 에너지 수준이 2,800 kcal/kg, methionine과 lysine, cystine의 수준은 단백질 수준에 비례하도록 하였다. 조사항목으로 산란율과 난중, 사료섭취량, 사료요구율, 계란품질은 4주 간격으로 측정했다. 실험 종료시 복강지방과 혈액중 total protein과 albumin, BUN, triglyceride, total cholesterol, HDL-cholesterol, LDL-cholesterol 함량, 간의 methionine, choline 함량, 간과 가슴육의 수분, 조단백질, 조지방 함량을 측정하였다. 산란율은 단백질 수준에 따라 증가하였으며(P<0.05) 비태인 급여에 의한 차이는 없었다. 난중은 단백질과 비태인 급여로 증가하였으며(P<0.05) 산란양은 단백질 수준이 증가할수록 감소하였다(P<0.05). 비태인 급여로 사료 요구율은 현저하게 개선되었지만(P<0.05), 계란의 품질은 차이가 없었다. 혈청 total protein은 비태인 급여로 현저히 증가하였으며 특히 단백질 14 % 급여구에서 크게 증가하였다(P<0.05). 복강지방 함량은 단백질 수준과 비태인 급여에 따라 감소하는 경향을 보였다. 가슴육과 간의 조단백질 함량은 사료의 단백질 수준에 따라 증가하였다(P<0.05). 간의 조지방 함량은 비태인의 급여로 감소하는 경향을 보였다. 간의 methionine 함량은 단백질과 비태인 수준에 따라 증가하는 경향을 보였으며 choline 함량은 비태인의 급여에 의해서만 증가하는 경향을 보였다. 따라서 비태인의 급여는 단백질 수준이 높은 조건에서 산란율을 개선시키고 난중을 증가시키며 사료 요구율을 개선한다.록 산가는 증가하는 것을 볼 수 있다. 홍국주의 전자 공여능에 의한 항산화력은 25.6%, 아질산염 소거능은 27.6%, Total phenolic compound 함량은 12.34mg%, ACE저해작용은 38%의 항산화력을 나타냈다.과 $O_2$$CO_2$의 농도에서 평균오차 0.2%로 정밀한 것으로 나타났으며 호흡속도 측정용 챔버의 혼합기체 공급측과 배기측의 가스 농도를 3회 반복 측정한 결과 재현성에서는 0.1%이하의 편차로 나타났다. 개방계 호흡속도 자동 측정 시스템을 이용하여 환경기체조성하에서 토마토의 호흡속도를 측정하는 실측 실험을 수행한 결과 2$0^{\circ}C$에서 12.7~42.1mg$CO_2$/kg.hr였으며 12$^{\circ}C$에서 2.5~8.2mg$CO_2$/kg.hr로 일반적으로 보고되고 있는 토마토 호흡속도와 일치하는 결과를 나타내었다.다.환원당인 sucrose 함량은 계속 증가하였고 fructose, glucose, sorbitol의 함량(추황의 sorbitol을 제외)은 생장이 촉진됨에 따라 증가하다가 다시 점차적으로 감소하였다. 이러한 결과는 총당과 환원당의 측정결과와 일치한 것으로 나타났다. 결론적으로 배의 성장에 따라 산 함량은 감소하였고 당 함량은 증가하였다.luco-pyranoside, quercetin 7-O- -glucopyranoside, acacetin 7-O-$\beta$-D-glucuronide and apigenin-6-C-$\beta$-D-glucopyranosyl-8-C-$\beta$-D-glucopyranoside were first isolated and identified from safflower leaf. Among these flavonoids, luteolin

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A study on the heat recovery Characteristics of double tube type heat recovery ventilation system by double pipe material (이중관 재질에 따른 이중관형 열회수 환기장치의 열회수 특성 연구)

  • Kim, Eun-Young;Cho, Jin-Pyo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.4
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    • pp.21-26
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    • 2017
  • In this study, performance tests were conducted to investigate the applicability of a double-tube heat recovery ventilation system. Paper, aluminum, polymer, were investigated as materials for the inner tube using the same exhaust-air volume. In all cases, the temperature exchange efficiency of the aluminum tube was the highest, while the paper tube showed similar results to those of the polymer tube. This probably resulted from the differences in thermal conductivity and thicknesses of the materials. The humidity exchange efficiency was the highest for the paper tubes in all cases, while the aluminum tubes and polymer tubes showed similar results. The total heat exchange efficiency, which includes the values of humidity exchange and temperature exchange, was highest in the case of the paper tube, and the aluminum tube and the polymer tube showed similar results. In the case of the paper tube, sensible heat and latent heat exchange occur at the same time, and the coefficient of energy of the aluminum tube and polymer tube are large values, when to be compared with only applicably sensible heat exchange coefficient of the aluminum tube and the polymer tube of total heat exchange efficiency value. The results of this study could be applied to the design of a ventilation system.

Task Analysis of Paramedics of Korea Based on DACUM Method (DACUM 기법에 의한 1급 응급구조사의 직무분석)

  • Bae, Ki-Sook;Koh, Bong-Yeun;Lee, Jung-Eun;Lee, In-Mo;Choi, Keun-Myoung;Kim, Soo-Tae
    • The Korean Journal of Emergency Medical Services
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    • v.15 no.1
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    • pp.5-23
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    • 2011
  • Objective : This study grasps specific task on paramedics who plays a great role in the emergency scene, thereby eliciting definition of job called paramedics and analyzing occupation by DACUM method. Thus, the aim is to suggest working-level guidelines on the task of paramedics. Methods : It targeted paramedics who are working at hospitals, fire stations, and industries in Seoul and Gyeonggi area from Oct. 11, 2010 to Nov. 30. A total of 608 copies of questionnaire were analyzed by DACUM method. A research tool on occupational analysis consisted of 8 pieces for duty, 43 pieces for task, and 149 pieces for task elements. In order to survey performance frequency, importance, and difficulty by element, each task was developed by this research team, and each task was analyzed and finally elicited through workshop of DACUM method. Results : The occupational definition of paramedics, which was defined through this DACUM, was elicited as 'professional job of performing emergency medical care on the scene, during transferring, or within medical institution in order to maintain life and prevent wound deterioration, targeting a person who is put in emergency situation.' Task element, whose performance frequency was indicated to be the highest, was in order of checking mental status($2.76{\pm}0.497$), checking vital signs($2.70{\pm}0.578$), and airway/c-spine immobilization($2.69{\pm}.546$). Especially, defibrillation stood at $2.23{\pm}.655$ points. Task element, whose performance frequency was low, was in order of caring sexual abuse victims($1.32{\pm}0.563$), performing cricothyrotomy($1.36{\pm}0.618$), and caring cardiac arrest victims($1.40{\pm}0.636$). Importance of task was in order of airway/c-spine immobilization ($2.88{\pm}0.338$), maintenance of respiration($2.88{\pm}0.351$), caring cardiac arrest victims($2.87{\pm}0.349$), and performing CPR($2.87{\pm}0.361$). Task element, whose importance is low, was indicated to be in order of enema($2.29{\pm}0.736$), urinary catheterization($2.35{\pm}0.664$), and nasogastric intubation($2.35{\pm}0.667$). Task element, whose difficulty was shown to be the highest, was indicated to be in order of caring cardiac arrest victims during pregnancy ($2.60{\pm}0.559$), caring cardiovascular injury($2.59{\pm}0.546$), and labor management($2.53{\pm}0.533$). Conclusion : Based on the results of this study, the job performance work table(Dacom chart) of paramedics is suggested to be used, thereby being applied to development in education and curriculum of paramedics. It is necessary to evaluate usefulness of the job performance work table by estimating effect of education for paramedics based on the job performance work table of paramedics.

Experimental Research on the Power Improvement by Increasing Intake pressure in a 1.4 L Turbocharged CNG Port Injection Spark Ignition Engine (1.4L 급 터보 CNG 엔진에서 흡기압력 상승에 따른 출력 증대 효과에 관한 연구)

  • Lee, Jeong-Woo;Park, Cheol-Woong;Bae, Jong-Won;Kim, Chang-Gi;Lee, Sun-Youp;Kim, Yong-Rae
    • Journal of the Korean Institute of Gas
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    • v.23 no.6
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    • pp.90-96
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    • 2019
  • Natural gas has been regarded as one of major alternative fuels, because of the increment of mining shale gas and supplying PNG(Pipeline Natural Gas) from Russia. Thus, it needs to broaden the usage of natural gas as the increasing its supplement. In this situation, application of natural gas on the transport area is a good suggestion to reduce exhaust emissions such as CO2(carbon dioxides) and soot from vehicles. For this reason, natural gas can be applied to SI(spark ignition) engines due to its anti-knocking and low auto-ignitibility characteristics. Recently, since turbocharged SI engine has been widely used, it needs to apply natural gas on the turbocharged SI engine. However, there is a major challenge for using natural gas on turbocharged SI engine, because it is hard to make natural gas direct injection in the cylinder, while gasoline is possible. As a result, there is a loss of fresh air when natural gas is injected by MPI (multi-point injection) method under the same intake pressure with gasoline-fueled condition. It brings the power reduction. Therefore, in this research, intake pressure was increased by controling the turbocharger system under natural gas-fueled condition to improve power output. The goal of improved power is the same level with that of gasoline-fueled condition under the maximum torque condition of each engine speed. As a result, the maximum power levels, which are the same with those of gasoline-fueled conditions, with improved brake thermal efficiency could be achieved for each engine speed (from 2,000 to 6,000 rpm) by increasing intake pressure 5-27 % compared to those of gasoline-fueled conditions.

An Optimization Study on a Low-temperature De-NOx Catalyst Coated on Metallic Monolith for Steel Plant Applications (제철소 적용을 위한 저온형 금속지지체 탈질 코팅촉매 최적화 연구)

  • Lee, Chul-Ho;Choi, Jae Hyung;Kim, Myeong Soo;Seo, Byeong Han;Kang, Cheul Hui;Lim, Dong-Ha
    • Clean Technology
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    • v.27 no.4
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    • pp.332-340
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    • 2021
  • With the recent reinforcement of emission standards, it is necessary to make efforts to reduce NOx from air pollutant-emitting workplaces. The NOx reduction method mainly used in industrial facilities is selective catalytic reduction (SCR), and the most commercial SCR catalyst is the ceramic honeycomb catalyst. This study was carried out to reduce the NOx emitted from steel plants by applying De-NOx catalyst coated on metallic monolith. The De-NOx catalyst was synthesized through the optimized coating technique, and the coated catalyst was uniformly and strongly adhered onto the surface of the metallic monolith according to the air jet erosion and bending test. Due to the good thermal conductivity of metallic monolith, the De-NOx catalyst coated on metallic monolith showed good De-NOx efficiency at low temperatures (200 ~ 250 ℃). In addition, the optimal amount of catalyst coating on the metallic monolith surface was confirmed for the design of an economical catalyst. Based on these results, the De-NOx catalyst of commercial grade size was tested in a semi-pilot De-NOx performance facility under a simulated gas similar to the exhaust gas emitted from a steel plant. Even at a low temperature (200 ℃), it showed excellent performance satisfying the emission standard (less than 60 ppm). Therefore, the De-NOx catalyst coated metallic monolith has good physical and chemical properties and showed a good De-NOx efficiency even with the minimum amount of catalyst. Additionally, it was possible to compact and downsize the SCR reactor through the application of a high-density cell. Therefore, we suggest that the proposed De-NOx catalyst coated metallic monolith may be a good alternative De-NOx catalyst for industrial uses such as steel plants, thermal power plants, incineration plants ships, and construction machinery.