• 한국산학기술학회논문지
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• 제11권8호
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• pp.2774-2779
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• 2010

본 연구에서는 도로 지하에 매설되어 있는 $2m{\times}2m$ 정도 규격의 박스형태 암거의 좁은 공간에서 준설작업을 할 수 있는 준설기 개발에 관하여 기술하고자 한다. 개발된 준설기는 버켓 구동식으로 동작하며, 지하에 매설된 암거의 내부를 지상에서 영상을 통해 인식하여 원격 조정이 가능하다. 위험한 작업환경에서도 준설작업이 가능하므로 개발결과를 상용화하고자 한다.

• 열병합발전
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• 통권36호
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• pp.16-21
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• 2003

For many years, T/G Supplier has constructed a number of thermal power plants and researched to improve the performance and the reliability of steam turbine, which are achieved by advances in design and materials technology. In recent, interest is renewed in advance steam condition as means of improving economy of thermal power plant and reducing environmental pollution. Improvements in the maximum power have been driven by the development of advanced rotor and bucket material and longer last stage bucket. Improvements in efficiency have been brought through advance in mechanical efficiency and thermodynamic efficiency. This paper describes a number of new steam path design features introduced to the steam turbine product. And also this paper describes new design technologies' development, new technologies' trend and technologies' development for ultra-super critical steam turbine.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.2174-2179
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• 2003

For many years, T/G Supplier has constructed a number of thermal power plants and researched to improve the performance and the reliability of steam turbine, which are achieved by advances in design and materials technology. In recent, interest is renewed in advanced steam condition as means of improving economy of thermal power plant and reducing environmental pollution. Improvements in the maximum power have been driven by the development of advanced rotor and bucket material and longer last stage bucket. Improvements in efficiency have been brought through advances in mechanical efficiency and thermodynamic efficiency. This paper describes a number of new steam path design features introduced to the steam turbine product. And also this paper describes new design technologies' development, new technologies' trend and technologies' development for ultra-super critical steam turbine.

• Journal of Biosystems Engineering
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• 제21권2호
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• pp.134-145
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• 1996

Since the skid-steer loader is able to work for excavating, lifting and transporting load even at the narrow space, they are widely used in the regular farm and the livestock farm. The skid-steer loader normally adopts the hydrostatic transmission because the power to move the machine backward and forward should be delivered independently on both sides of wheels. Contrast to the mechanical system such as chain and belt transmissions, however, the hydrostatic transmission is less efficient in the use of energy and more difficult in the maintenance. This study was intended to investigate the feasibility of using triangular-type belt clutch and V-belt transmission for the newly developed skid-steer loader in order to overcome the problems stated in the hydrostatic transmission. In the developed triangular-type belt clutch, the centers of driving, driven and idler sheaves are arranged in the triangular shape in a plane, and V-belts were loaded loosely on three sheaves. The power is transmitted by pressing the idler connected to a lever on the loosened V-belt. Contrast to the normal belt clutch using two sheaves, the newly developed belt clutch has the characteristics of small contact-angle of the driving sheave at no bucket load and increasing contact-angle at the time of power transmission. The results of research can be summarized as follows: 1) The developed triangular-type belt clutch adopted a spring-loaded slackside idler which could transmit more power than a fixed idler could by sacrificing the belt life. The life of V-belt used in the power transmission reached at 500 hours(6 months) when the engine power of 11.8 ㎾ was transmitted. Also, it was feasible to develop the large industrial skid-loader with the V-belt transmission by using the proper set of sheaves. 2) The developed skid-steer loader changed the rotating radius and speed with bucket loads as the conventional skid steer loader did. The rotating speed was 47 deg/s at the maximum bucket load of 2.74 kN when the minimum rotating radius was 1.5m. 3) The power required in turning at the bucket load of 2.74 kN was 4 ㎾ and the slippage of V-belt was less than 1%.

• 한국해안·해양공학회논문집
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• 제25권3호
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• pp.123-127
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• 2013

본 논문에서는 해상풍력발전터빈의 기초형식 중 하나인 버켓기초의 관입시 발생할 수 있는 좌굴거동에 대한 연구를 수행하였다. 유한요소를 사용하여 대상구조물을 모델링하고 현재 설계기준의 기본인 원통형 쉘의 좌굴거동을 해석하여, Batdorf의 계수에 따라 설계기준에 제시된 식과 비교하여 모델의 검증을 수행하였다. 검증된 해석 모델을 바탕으로 인접한 지반의 영향 및 하중조건을 적용하고 종방향보강재와 관입깊이가 좌굴성능에 미치는 영향을 평가하였다. 평가결과 종방향보강재의 적용은 특정영역에서 좌굴강도를 크게 증가시키고 인접한 지반의 영향은 관입에 따라 선형적으로 증가하는 것으로 나타났다.

• Journal of Biosystems Engineering
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• 제24권2호
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• pp.145-152
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• 1999

Methods of discharging each graded agricultural product are divided into two according to the type of feeding. One is based on feeding objects using a series of specially designed holders mounted with an equal interval. The other is randomly feeding objects while being isolated without a specific interval. In this paper, a real time simultaneous discharge algorithm, which is good for objects randomly fed individually and for multi-objects located along a series of discharge buckets, was developed. And the developed algorithm was implemented to the controller and the performance was verified using the system developed for dried mushrooms. The discharge system used for the experiment was composed of a variable speed conveyor, a series of double channel bucket mounted along both sides of the conveyor, and a series of air nozzles and optic sensors. Developed algorithm worked perfectly and could be directly used for automatic discharge system for randomly feeding agricultural products.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.550-551
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• 2013

Large-area RF-driven ion source is being developed at Germany for the heating and current drive of ITER plasmas. Negative hydrogen (deuterium) ion sources are major components of neutral beam injection systems in future large-scale fusion experiments such as ITER and DEMO. RF ion sources for the production of positive hydrogen ions have been successfully developed at IPP (Max-Planck- Institute for Plasma Physics, Garching) for ASDEX-U and W7-AS neutral beam injection (NBI) systems. In recent, the first NBI system (NBI-1) has been developed successfully for the KSTAR. The first and second long-pulse ion sources (LPIS-1 and LPIS-2) of NBI-1 system consist of a magnetic bucket plasma generator with multi-pole cusp fields, filament heating structure, and a set of tetrode accelerators with circular apertures. There is a development plan of large-area RF ion source at KAERI to extract the positive ions, which can be used for the second NBI (NBI-2) system of KSTAR, and to extract the negative ions for future fusion devices such as ITER and K-DEMO. The large-area RF ion source consists of a driver region, including a helical antenna (6-turn copper tube with an outer diameter of 6 mm) and a discharge chamber (ceramic and/or quartz tubes with an inner diameter of 200 mm, a height of 150 mm, and a thickness of 8 mm), and an expansion region (magnetic bucket of prototype LPIS in the KAERI). RF power can be transferred up to 10 kW with a fixed frequency of 2 MHz through a matching circuit (auto- and manual-matching apparatus). Argon gas is commonly injected to the initial ignition of RF plasma discharge, and then hydrogen gas instead of argon gas is finally injected for the RF plasma sustainment. The uniformities of plasma density and electron temperature at the lowest area of expansion region (a distance of 300 mm from the driver region) are measured by using two electrostatic probes in the directions of short- and long-dimension of expansion region.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.241.1-241.1
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• 2014

The large-area high-power radio-frequency (RF) driven ion sources based on the negative hydrogen (deuterium) ion beam extraction are the major components of neutral beam injection (NBI) systems in future large-scale fusion devices such as an ITER and DEMO. Positive hydrogen (deuterium) RF ion sources were the major components of the second NBI system on ASDEX-U tokamak. A test large-area high-power RF ion source (LAHP-RaFIS) has been developed for steady-state operation at the Korea Atomic Energy Research Institute (KAERI) to extract the positive ions, which can be used for the NBI heating and current drive systems in the present fusion devices, and to extract the negative ions for negative ion-based plasma heating and for future fusion devices such as a Fusion Neutron Source and Korea-DEMO. The test RF ion source consists of a driver region, including a helical antenna and a discharge chamber, and an expansion region. RF power can be transferred at up to 10 kW with a fixed frequency of 2 MHz through an optimized RF matching system. An actively water-cooled Faraday shield is located inside the driver region of the ion source for the stable and steady-state operations of RF discharge. The characteristics and uniformities of the plasma parameter in the RF ion source were measured at the lowest area of the expansion bucket using two RF-compensated electrostatic probes along the direction of the short- and long-dimensions of the expansion region. The plasma parameters in the expansion region were characterized by the variation of loaded RF power (voltage) and filling gas pressure.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.179.2-179.2
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• 2013

A large-area RF-driven ion source is being developed at Germany for the heating and current drive of ITER device. Negative hydrogen ion sources are major components of neutral beam injection (NBI) systems in future large-scale fusion experiments such as ITER and DEMO. The RF sources for the production of positive hydrogen ions have been successfully developed at IPP (Max-Planck-Institute for Plasma Physics), Garching, for the ASDEX-U and W7-AS neutral beam heating systems. Ion sources of the first NBI system (NBI-1) for the KSTAR tokamak have been developed successfully with a bucket plasma generator based on the filament arc discharge, which have contributed to achieve a good plasma performance such as 15 sec H-mode operation with an injection of 3.5 MW NB power. There is a development plan of RF ion source at the KAERI to extract the positive ions, which can be used for the second NBI system (NBI-2) of the KSTAR and to extract the negative ions for future fusion devices such as Fusion Neutron Source and Korea-DEMO. The development progresses of RF ion source at the KAERI are described in this presentation.