• 월간낙농육우
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• s.41
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• pp.18-20
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• 1985

비육사업은 소값 하락과 지육값 하락으로 불안정하여 불안한 실정에 놓여 있어 이 불황이 하루속히 회복되기를 바라면서 조수익을 최대로, 경영비를 최소로 하는 합리화방안을 생각해 보기로 한다.

• Korean Journal of Agricultural Science
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• v.2 no.2
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• pp.415-422
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• 1975

This experiment was conducted to study the effect of supplementation of fowl excrement for pig feed and econmic value of using fowl excrement for pig production. 1) The gain of body weight was no significant difference between the groups at the end of experiment. 2) The amount of feed intake by the amount of fowl excrement supplementation was increasing for 20% fowl excrement added group was 3.13 and 40% fowl excrement added group was 4.10 then control group was 2.68. 3) The digestibility of concentration was decreasing by the amount of fowl excrement supplementation. 4) The analysis on the economic low income indicated that the income for 20% fowl excrement added group was 460.87 won and 40% fowl excrement added group was 985.27 won.

• Journal of the Korean Society of Propulsion Engineers
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• v.11 no.4
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• pp.10-18
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• 2007

A tested micro axial-type turbine consists of two stages and its mean radius of rotor flow passage is 8.4 mm. This turbine could be applied to a driver of micro power system, and its rotational speed in the unloaded state reaches to 100,000 RPM. The performance of this system is sensitive depending on the blade angles of the rotor and stator because it is operated in a low partial admission rate, so a performance test is conducted through measuring the specific output power and the net specific output torque with various blade angles on the nozzle, stator and rotor. The experimental results show that the net specific output torque is varied by 15% by changing the rotor blade angle, and the optimal incidence angle is about $10.3^{\circ}$.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1460-1463
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• 2010

Railway has been pointed to the efficiency of transportation, rapid transit, and comfortable train ride. the construction of railway near the downtown area and station building are increasing for maximization of utilization and convenience. but the heavy of transportation and rapid transit lead to increase noise and vibration. The noise and vibration of railway may cause the civil appeal, decline in the serviceability and insufficiency of environmental standard. In this study, floating slab vibration and repeated connection of devices to support joints and fatigue stress analysis of punching shear performance review was conducted to evaluate the safety.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1452-1459
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• 2010

Application of long-span bridge, which is affected by parameters such as span length, shoe boundary condition, track property and stiffness of superstructure and substructure etc., can vary. Especially, by CWR aspects of the axial force, that can be less constraints of construction depending on whether the application of rail expansion joint(REJ), which has disadvantaged in terms of maintenance. In this study, it was performed parameter study for multiple variables (shaft length, the upper and lower cross-section characteristics, track characteristics, etc.) in terms of CWR aspects. Structure-rail interaction analysis was applied to the typical simple span PSC Box and 3 span continuous bridge Extradosed Bridge(50m+80m+50m) excluding REJ. If you set the boundary e of variables for long-span railway bridge excluding REJ through the this study, when designing future is expected to be able to useful.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.2353-2355
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• 2010

Since the efforts in transportation for counteracting Climate Change have been enhanced, it is necessary to reduce GHG emissions from railroad construction. The aim of this study was to develop the calculation method of GHG emissions at the step of railroad construction. Main emission source was the energy consumption from the used heavy equipments. Firstly, GHG inventory including equipments list, energy consumption, and work load was established with the detailed process using standard for the unit cost of construction. Also, the energy consumption of heavy equipments during track construction at A site was collected to compare with the field data. As a result, the GHG emissions between the estimated and the field were a little different, which was caused by the inaccurate field data. Therefore, it is important to manage data efficiently for the calculation of GHG emissions in the field of railroad construction.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.268-272
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• 2010

Recently the construction of railway sections passing the central area of cities and stations under railway lines are increasing, and then it is urgently required to take the countermeasures against the railway vibration and the second-phase noise radiated from it. The most efficient countermeasure, out of technologies developed up to now, is the floating slab track which is the track system isolated from the sub-structure by springs. In other countries, the source technologies for anti-vibration design and vibration isolator - one of key components - have been developed and many installation experiences have been accumulated. However, in Korea, since the system design technology and technologies for key components are not yet developed, the foreign system are being introduced without any adjustment, and the key component, vibration isolator, depends on imports. In this study, floating slab was divided into three spans, $k_{dynamic}$ use by examining reactions and member forces was to ensure safety.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.249-255
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• 2010

Ballasted track is under the circumstance of repetition of deterioration and recovery. Track deterioration is presented as track irregularity or settlement, and dynamic force subjected to track is one of major cause of the deterioration. The dynamic force is determined from the dynamic interaction between track and vehicle. Rail-pad stiffness is one of the factor affects track dynamic property. In this study, the relationship between rail-pad stiffness and track settlement was investigated. Dynamic forces according to various rail-pad stiffness was obtained from the dynamic vehicle-track interaction analysis using DARTS-NL. Track settlement was calculated by substitution the dynamic forces into various formulas for track settlement. From the result of analysis, it was known that the track settlement is increased about 6% when the rail-pad stiffness rise about twice. And this result leads that there is only a little relationship between rail-pad stiffness and track settlement.

• Journal of the Korean institute of surface engineering
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• v.30 no.4
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• pp.239-247
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• 1997

The electrochemical machining of carbon steel was carried in various electrolytes which contain NACl and $NaCIO_3$. Though electrolyte containg NaCl yields fast machining rate, dimensional control is rather difficult. In the case of electrolyte with $NaCIO_3$, dimensional control of anode shape can be obtained through modification of cathode design. Mathematical modeling is also performed for these systems and agreements are good compared with experimental date. The constant gap experiment butween two electrode yielded faster machining rate than constant cathode moving rate experiment.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.560-564
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• 2009

절도시설과 같은 광역지역 공사 현장에서는 다양한 요인을 갖는 공종별 위험요소가 존재하고 있으나, 현장에서 이를 효율적으로 관리할 수 있는 방안의 수립이 미흡한 실정이다. 따라서 본 연구에서는 철도 관련 실무자들을 대강으로 설문조사를 실시하여 공종별 위험 요인을 도출한다. 이를 통해 RBS(Risk Breakdown Structure)를 구축하고 제시된 RBS에 의한 위험도를 산정한 후 이를 기반으로 VR시스템과의 연동 및 위험관리 체계 구축 방법론을 제시하고 있다. 따라서 현장에서의 주요 공종별 Risk 위험도를 가상환경에서 구현이 가능하므로 위험요인에 따른 시설의 직관적 파악이 가능하다. 또한 시공자들은 나타난 시각화 정보에 의한 Risk에 대비해 효율적인 공사 관리를 이행할 수 있을 것으로 기대된다.