• The Journal of the Acoustical Society of Korea
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• 제15권2E호
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• pp.63-75
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• 1996

The squeal vibration of a drum is the major source of brake noise. In this system the binary flutter model of squeal vibration was employed for the drum brake of a passenger car. The vibration analysis of a drum brake was performed by using normal modes, which are obtained by variational method. An improved method for the estimation of shoe modes is proposed and the results are compared with the exact solutions. Numerical results for the coupled system of drum and shoes good agreement with the results of experimental model analysis and those obtained by FE analysis.

• 한국전산유체공학회지
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• 제16권1호
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• pp.67-72
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• 2011

HRSG (Heat Recovery Steam Generator) is a boiler to recover heat from the exhaust gas of an engine and to generate steam for more power generation or process. For the HRSG, water-tube type boiler is commonly adopted to accommodate the working pressure or capacity requirement of the system. The water-tube type boiler has a steam drum to separate steam from the water-steam mixture supplied from the evaporator tube (riser). The drum should be sized properly to separate the steam by the gravity and auxiliary internals, such as a demister, which are installed to filter the steam. To size the steam drum and to estimate the filter efficiency of drum internals, the velocity distribution inside the drum needs to be identified. In the present study, a series of CFD has been conducted to find the velocity distributions inside steam drums for conventional HRSGs and water-tube type industrial boilers. The velocity distributions obtained from the simulation have been normalized and a correlation to predict them has been found. The correlation is applied to the steam drum design by determining a proper position of a demister to show proper separation performance.

• 한국생산제조학회지
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• 제19권5호
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• pp.684-690
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• 2010

A drum cam with rotational follower has a cam mechanism and it is mainly used in its application such as index table and ATC of machine tool. Also its use can reduce the backlash in its kinematic movement. To machine the drum cam with rotational follower, 5-axis CNC machine tool is generally used and its kinematic principle is included in it's design. Until now, the commercialized CAM software can't cover the application of the drum cam machining. Even if, some special software was developed for machining a drum cam, the post processing method for finish machining was not developed yet. And to overcome the problem, the form tool is still used on the tool path of rough machining. This study includes the induction of the post processing technique for the finish machining of drum cam on three 5-axis CNC machine tools, type AC, AB and BC. To prove the finishing geometric profile, the result was clearly verified through inspection and geometric measurement after direct machining of the drum cam in AC type 5-axis machine tool in this study.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2006년도 춘계 종합학술대회 논문집
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• pp.215-219
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• 2006

일반적으로 정적인 공간에서 게이머 단독으로 진행하는 게임의 만족도는 높게 나타난다. 그러나 이들 게임에는 공격적, 폭력적 양상의 비교육적인 측면도 없지 않다. 또한 장시간 게임 활동에 따른 정신적, 신체적 폐해가 게임 중독으로까지 이어져 사회문제로 대두되고 있는 것이 현실이다. 최근, 이러한 문제점의 대안으로 가족이 참여하거나 하나의 미션을 협력하여 해결하는 협동게임이 연구되고 있다. 본 논문에서는 협동적 음악기기로 개발된 재모드럼을 분석하고 4명이 참여하여 게임 콘텐츠에 따라 각자, 2인1조 또는 4인1조의 형태로 협동성 증진 게임을 진행할 수 있는 한국형 코모드럼을 제안하였다. 또한 한국의 장구를 응용한 사용자 인터페이스 설계와 활용방안을 소개한다.

• 한국염색가공학회지
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• 제12권1호
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• pp.68-75
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• 2000

In this study, polyester DTY faille(yoryu) and N/NP microfiber fabrics were pretreated (desizing, scouring and shrinking) by Continuous Scouring and Shringking Equipment with rota-drum and conveyor type in which types were different with retaining method. The results were as follows. The shrinkage ratio of wp/wf direction of DTY fabrics scoured by conveyor type was 1.5/23% higher than those by rota-drum type at $97^\circ{C}$ with 10min. treatment. In this case, The shrinkage ratio of wp/wf direction by those types was about 15/27%, respectively. The shrinkage ratio of wp/wf direction of N/NP microfiber fabrics scoured by conveyor type was 1.5/23% higher than that by rota-drum type at $97^\circ{C}$ with 10min. treatment. The size add-on of DTY fabrics scoured at $97^\circ{C}$ with 10min. treatment by conveyor type and by rota-drum type were 0.15% and 0.42%, respectively. The size add-on of DTY fabric treated by rota-drum type decreased until 9min. of treated time, but increased after 9min. The size add-on of N/NP microfiber fabrics treated by conveyor type was decreased by increasing temperature and treated time, while the size add-on of that treated by rota-drum type was decreased until 6min. treated time and increased after 6min. The size add-on of N/NP microfiber fabrics treated by conveyor type at $97^\circ{C}$ for 10min. was 0.3% lower than that by rota-drum type.

• 한국기계기술학회지
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• 제13권3호
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• pp.65-71
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• 2011

The concrete mixer truck which is in charge of raw materials in civil engineering construction of the concrete loading, transport, placement, is used $6m^3$, $7m^3$ class in domestic(Korea). But in the case of the international construction fields are utilized $9m^3$ or above class because of the large-scale engineering and construction circumstances. In this paper, to develop a large $9m^3$ class mixer drum and the mixer drum in order to complement the technical and discharge that is responsible for stirring the blades by applying optimal design through implementation of the optimal shape of the concrete in the drum maintenance and placement of high-quality effects on increasing discharge such as advanced conventional drum mixer is to secure and differentiated technology. Large, heavy weight in development and uphold the drum mixer vehicle sub-frame is required to settle the design of the existing class mixer drum frames per $6m^3$ changed to account for changes in slope and length using CATIA V5 3D modeling work was performed.

• 수산해양기술연구
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• 제41권3호
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• pp.199-206
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• 2005

As the basic study about improvement of yellow croaker drift gill net fishing implement and development of the fishing system, this study drew problem after synthetically analyzing hauling system of yellow croaker drift gill net used in the coast of Chuja Island and tested several characters and analyzed in hauling process with 5 step net hauler model for improving the problem. The analysis results are as follows. When the angle between axises of drum centers was small, it showed the tendency that hauling time was fast. Hauling time was faster when drum was 5 step rather than 3 step. When drum was 5 step, slippery phenomenon was small and hauling was stable. Tension was larger when drum was 5 step rather than 3 step. When drum was 5 step, the range of change of the maximum and minimum value was small and hauling was stable. When drum was 3 step, there was following formula between hauling time ($Ht_3$) and angle between axises of drum centers ($A_g$) $Ht_3$ : ($7.15Hs^{-0.81}$) $A_g^{-0.81}$, when drum was 5 step there was following formula.$Ht_5$ : ($6.45Hs^{-0.75}$) $A_g0.10$, here, Hs is hauling speed. When drum was 3 step and hauling speed was 28cm/sec, tension was $T=0.08A_8^3-1.60A_g^3-0.49A_g+369.56(r=0.99)$, when drum was 5 step, tension was, $T=-0.01A_g^3+1.96A_g^2-34.05A_g+414.58$ (r-0.99), here, T was tension(g).

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2004년도 춘계학술대회 논문집
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• pp.88-92
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• 2004

We developed a helical type drum with an oblique cutting condition for sawdust machine. The existing drum has an orthogonal cutting(2D) condition considering of saw cutter and wood cutting pattern. Additional disadvantage of this type include big cutting resistance, high cost of cutting power and extreme occurrence of vibrations. To improve this shortcoming, we developed a helical type drum with an oblique cutting(3D) condition, therefore, this type drum decreased the vibration and cutting resistance of sawdust machine, and also improved productivity and sawdust porosity.

• Journal of Microbiology and Biotechnology
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• 제14권3호
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• pp.435-441
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• 2004

A drum bioreactor was used for the treatment of sandy soil contaminated with three kinds of aromatic compounds (phenol, naphthalene, and phenanthrene), and its performance was evaluated in two different operation modes; intermittent and continuous rotation of drum. When the drum bioreactor was operated with one rotation per day, the microbial growth was relatively low, and most of the compounds remaining in soil, except naphthalene of 90 mg/kg dry soil, disappeared mainly due to volatilization. In contrast, when the drum was continuously rotated at 9 rpm (rotation/min), the number of microorganisms was drastically increased and nitrate was consumed for growth as a nitrogen source. Phenol and phenanthrene were removed at rates of 56.7 mg/kg dry soil/day and 3.2 mg/kg dry soil/day, respectively.

• 한국기계가공학회지
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• 제2권3호
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• pp.90-95
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• 2003

The W-EDM is very important In precision machining of die, punch and small parts of precision products, so this machining method is widely used in various fields of industry. In this study, machining characteristics of Hand Drum Form and surface roughness are investigated experimentally. As Hand drum form has great effect on straightness of cut-surface of workpiece, its evaluation is very important in precision cutting. As experimental material, the mold material, STD11 is used and machined by CNC wire-EDM using the 025mm wire in diameter with repeated cutting up to 6 times. The thickness of workpiece is vaned in 20, 40, 60, 80, 100mm Hand drum form and surface roughness are measured after each cutting. Experimental results show that four times-cutting is optimum in the point of hand drum form and surface roughness.