• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.17 no.2
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• pp.203-212
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• 2019

Disposal nonconformity of radioactive wastes refers to radioactive wastes that need to be treated, solidified and packaged during operation or decommissioning of NPPs, and are typically exemplified by particulate radioactive wastes with dispersion characteristics. These wastes include the dried powders of concentrated wastes generated in the process of operating NPPs, slurry and sludge, various powdered wastes generated in the decommissioning process (crushed concrete, decontamination sludge, etc.), and fine radioactive soil, which is not easy to decontaminate. As these particulate wastes must be packaged so that they become non-dispersive, they are solidified with solidification agents such as cement and polymer. If they are treated using existing solidification methods, however, the volume of the final wastes will increase. This drawback may increase the disposal cost and reduce the acceptability of disposal sites. Accordingly, to solve these problems, this study investigates the pelletization of particulate radioactive wastes in order to reduce final waste volume.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.6
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• pp.31-38
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• 2002

This paper presents the analysis of the flight test data measured by the sensors installed on a four-seat canard aircraft. The inherent stall proof characteristics of canard aircraft was verified from the stall test. The dihedral effect, adverse yaw and roll control power were examined and the neutral point that determines the longitudinal stability of the aircraft was investigated. The dynamic characteristics such as dutch roll mode were also examined. Without relying on the parameter identification method, the aerodynamic derivatives or the relations between the aerodynamic derivatives were obtained by analyzing the steady state flight data.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.243-246
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• 2003

Poly(butylene terephthalate)(PBT) is an important engineering polyester. It crystallizes much more easily and faster than PET. And these crystallization properties determine its use as an injection molding resin. Although it is more extensive than PET, its crystallization can be controlled much more easily during processing. General electric (Schenectady, NY) is the main producer of PBT films. Its production capacity was 3-5million pounds per year in 1987. (omitted)

• Journal of the Korean Institute of Intelligent Systems
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• v.8 no.4
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• pp.8-17
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• 1998

Autonomous mobile robot agents(AMRAs) are robots which perform a given task by the same distributed self-organizing rules. In this paper, we let them form an equi-distance circle for the task of cooperative behaviors. Here, we suggest an algorithm to perform the taqk and then utilize a fuzzy system to improve the algorithm. It is shown that various cooperative activities appear in the simulation and particularly chaotic behaviors also appear by increasing the robot speed. Moreover, we prove the characteristics of this chaotic behaviors by calculating Lyapunov exponent.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1999.07a
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• pp.234-239
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• 1999

고추는 대부분 건고추를 굵은 고춧가루, 보통 고춧가루, 고운 고춧가루로 분쇄하여 김치류, 고추장 등의 발효식품과 양념류에 주로 사용되고 있으며, 국민 일인당 연간 소비량은 고춧가루를 기준으로 2.5kg, 건고추를 기준으로 3.5kg에 이르고 있다. 건고추를 가루로 분쇄하는 방법은 종래 절구로 찧어 빻는 방법에서 생산성을 높이기 위하여 1960년대 중반부터 국내 특유의 압축식 롤 밀(Roll Mill)형태의 분쇄방법으로 전환되었으며, 구미의 햄머 밀이나 디스크 밀에 의한 분쇄방법과는 차이가 있다. 이것은 소비형태에 의한 차이로서 우리는 발효식품의 숙성을 위하여 고춧가루의 수축복원력을 향상시키는 방법으로 고추과피의 섬유질을 압축력과 전단력을 이용하여 분쇄하는 형태인 반면에, 구미에서는 고춧가루를 단순히 조미향신료의 첨가제로 사용하는 차이점 때문이다. (중략)

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1389_1390
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• 2009

펄스파워 전원장치에서 전류펄스 파형을 성형하기 위해 인덕터를 이용한다. 이 인덕터는 고주파용이므로 철심(core)이 없는 공심이어야 하며, 또한 표피효과(skin effect)로 인한 저항손실의 영향을 줄일 수 있는 구조로 제작되어야 한다. 표피효과를 줄이기 위해서, 인덕터는 권선의 동판을 3장 겹쳐서 나선형으로 감은 젤리롤(jelly roll)형으로 제작하였고, 실험을 통하여 인덕턴스값과 저항값을 측정한 결과를 소개 하고자 한다.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.10a
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• pp.91-96
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• 2001

When it is considered that many vehicle rides on the road and ride quality is an important method to evaluate vehicle performance with handling, running-over-bump manoeuvre may be suitable for testing ride quality. In this paper, a computed model has roughly steering system and lumped mass, connected by joint each rigid body, and suspension that has beam elements and has shock absorber as force element to represent nonlinear characteristics. A computer simulations for passing over a bump were made with two velocities. One side of vehicle passed over bump in due consideration of driver's habit that driver is subject to avoid a bad ride quality. On simulation, vertical acceleration, pitch angle and roll angle were measured at the mass center of chassis each case.

• Proceedings of the KAIS Fall Conference
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• 2011.12b
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• pp.646-648
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• 2011

본 논문에서는 쌍롤 박판주조(Twin Roll Casting, TRC)법을 이용하여 AA4343 합금을 제작하였다. 주조시 롤 간격을 조절하여 냉각속도를 달리하였으며 인고트 주조(Ingot Casting, IC)법을 이용하여 제조된 합금과의 미세조직학적 차이와 이에 따른 물성 변화를 고찰하였다. TRC 및 IC로 제조된 합금을 냉간압연하였으며 압연 건전성을 평가하였다. 한편, 냉각속도별로 상이한 미세조직을 구현할 수 있는 스텝몰드(Step Mold Casting, SMC)법을 이용하여 제조된 합금의 냉각속도에 따른 미세조직 및 경도 차이를 조사하여 상대 비교하였다. 냉각속도가 빠를수록 주조 셀조직의 크기 및 공정 Si 입자의 크기가 감소하였으며 이로 인하여 경도가 증가되는 효과를 나타내었다. 주조시 생성된 공정 Si 입자의 크기는 압연에 의하여 그 크기의 변화가 거의 없었으며 열분석 결과 액상선 온도의 변화가 일부 발생하나 큰 차이가 없었다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.04a
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• pp.551-555
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• 1996

The continuing demand for quality products requires better understanding and improved control of the production process. And, in recent year requirements for flatness control in strip rolling have become increasinglysevere because of the control for flatness of cold rolled strip is essential for further down stream processing. Also a speeds of rolling mills to meet productivity requirements puts a demanding requirement on the control of flatness of rolled strip. The demands on a total flatness control system therefore are a measuring and indication system consisting of a measuring roll that is robust, accurate, reliable and require a minimum of maintenance. The critical prt of any control system is the quality of the information being provided by the measurement instrument or device. It is therfore of utmost importance to have an accurate, repeatable and reliable measuring system. So, in this paper, The measuring roll for automatic flatness control system of contact type has been investigated.

• Journal of Power System Engineering
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• v.14 no.4
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• pp.5-10
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• 2010

This study was investigated the effect on operating characteristics of apparatus according to frosting and defrosting to develop of new defrosting equipment. The results showed as following. Frost was almost removed using the defrosting equipment with roll brush type that defrosting is possible under operating condition. Also, the temperature of compressor inlet, evaporator inlet and outlet showed higher value because of heat transfer resistance of cooling pipe frost comparing with defrosting condition. And the compressor work showed 10% lower and COP was presented 24% higher values than defrosting condition. Therefore, defrosting for cooling coil of refrigeration and low temperature storage was effected on operation and performance characteristics of equipment. This highly effects on real refrigeration apparatus which is operated in year-around.