• 한국표면공학회:학술대회논문집
• /
• 한국표면공학회 2016년도 추계학술대회 논문집
• /
• pp.105-105
• /
• 2016

Recently, high power impulse magnetron sputtering (HIPIMS) has attracted considerable attentions due to its high potential for industrial applications. By pulsing the sputtering target with high power density and short duration pulses, a high plasma density and high ionization of the sputtered species can be obtained. HIPIMS has exhibited several merits such as increased coating density, good adhesion, microparticle-free and smooth surface, which make the HIPIMS technique desirable for synthesizing hard coatings. However, hard coatings present intrinsic defects (columnar structures, pinholes, pores, discontinuities) which can affect the corrosion behavior, especially when substrates are active alloys like steel or in a wear-corrosion process. Atomic layer deposition (ALD), a CVD derived method with a broad spectrum of applications, has shown great potential for corrosion protection of high-precision metallic parts or systems. In ALD deposition, the growth proceeds through cyclic repetition of self-limiting surface reactions, which leads to the thin films possess high quality, low defect density, uniformity, low-temperature processing and exquisite thickness control. These merits make ALD an ideal candidate for the fabrication of excellent oxide barrier layer which can block the pinhole and other defects left in the coating structure to improve the corrosion protection of hard coatings. In this work, CrN/Al2O3/CrN multilayered coatings were synthesized by a hybrid process of HIPIMS and ALD techniques, aiming to improve the CrN hard coating properties. The influence of the Al2O3 interlayer addition, the thickness and intercalation position of the Al2O3 layer in the coatings on the microstructure, surface roughness, mechanical properties and corrosion behaviors were investigated. The results indicated that the dense Al2O3 interlayer addition by ALD lead to a significant decrease of the average grain size and surface roughness and greatly improved the mechanical properties and corrosion resistance of the CrN coatings. The thickness increase of the Al2O3 layer and intercalation position change to near the coating surface resulted in improved mechanical properties and corrosion resistance. The mechanism can be explained by that the dense Al2O3 interlayer acted as an excellent barrier for dislocation motion and diffusion of the corrosive substance.

• 한국분말야금학회:학술대회논문집
• /
• 한국분말야금학회 1994년도 춘계학술대회강연 및 발표대회 강연및 발표논문 초록집
• /
• pp.6-6
• /
• 1994

Har dmaterials such as cemented carbides with or without coated layer, cermets, ceramics and diamond or c-BN high pressure sintered compact are used for cutting tools, wear -resistant parts, rock drilling bits and/or high pressure vessels. These hardmaterials contain not only hard phase, but also second consituent as the element for forming ductile phase and/or sintering aid, and the mechanical properties of each material depend on (1) the amount of the second constituent as well as (2) the grain size of the hard phase. The hardness of each material mainly depends on these two factors. The fracture strength, however, largely depends on other microstructur a1 factors as well as the above two factors. For all hardmaterials, the fracture strength is consider ably affected by (3) the size of microstructur a1 defect which acts as the fracture source. In cemented carbides, the following factors which are generated mainly due to the addition of the second constituent are also important; (4) the variation of the carbon content in the normal phase region free from V-phase and graphite phase, (5) the precipitation of $Co_3$ during heating at about $800^{\circ}C$,(6) the domain size of binder phase, and (7) the formation of ${\beta}$-free layer or Co-rich layer near the surface of sintered compacts. For cemented carbides coated with thin hard substance, the important factors are as follows; (8) the kind of coated substance, (9) the formation of ${\eta}$-phase layer at the interface between coated layer and substrate, (10) the type of residual stress (tension or compression) in the coated layer which depends on the kind of coating method (CVD or PVD), and (11) the properties of the substrate, and (12) the combination, coherency and periodicity of multi-layers. In the lecture, the details of these factors and their effect on the strength will be explained.

• 산업진흥연구
• /
• 제3권1호
• /
• pp.33-42
• /
• 2018

본 연구는 리더의 비인격적인 행동에 대한 조직구성원의 반생산적 과업행동에 미치는 영향과 조직지원인식의 조절효과를 검증하였다. 충남과 세종, 대전시의 자동차부품산업 중소기업체를 대상으로 설문조사를 실시한 결과 상위리더의 비인격적 행동은 중간리더의 비인격적 행동에 유의한 영향(p<.001, ${\beta}=.910$)을 미쳤으며, 조직의 상위리더의 비인격적 행동 중 부정행동과 모욕행동은 중간리더의 학력과 상사와 함께 근무한 기간이 유의한 영향을 미쳤다. 또한 상위리더의 경우 부정행동과 구성원의 조직에 대한 반생산적 과업행동에 조절효과가 있는 것으로 확인되었다. 본 연구 결과를 통해 상위리더의 비인격적 행동에 대한 중간리더의 비인격적 행동의 적하현상을 밝힘으로써 조직구성원의 반생산적 과업행동으로 인한 경제적 손실과 사회적 손실을 감소시킬 수 있는 시사점을 제공한 데 그 의의가 있다.

• 대한전자공학회논문지SP
• /
• 제41권2호
• /
• pp.11-22
• /
• 2004

겹쳐진 물체의 분리에 대한 기존의 연구들은 주로 모델기반 정합방법을 사용하고 있어서 적용가능물체가 2차원물체에 한정되었고, 모델물체의 수가 증가하면 정합과정에 소요되는 시간이 지수적으로 증가하는 문제를 갖는다. 이러한 문제를 해결하기 위해 본 논문에서는 곡면을 포함하는 3차원물체를 대상으로 물체에 대한 정보가 없는 상황에서도 가리는 물체를 찾아내는 알고리즘을 제시한다. 이 방법을 이용함으로써 겹쳐진 물체의 인식이 독립된 하나의 물체를 인식하는 문제로 단순화될 수 있다. 제안하는 알고리즘은 물체를 면의 결합으로 해석하고 면들은 경계선을 속성으로 표현된다. 3차원 물체의 겹침은 2차원 영상에서 면의 겹침으로 보여 지고 면의 겹침은 경계선의 교차로 나타나는 특성을 이용하여 겹침의 형태를 경계선의 형태로 일반화하여 분류하는 기법을 사용하였다. 면사이의 겹침 관계를 면특징 관계도를 이용하여 표현하기 위해 관계계수를 정의하였고 관계계수의 값은 겹침의 형태를 보여주도록 개념화하였다. 제안된 알고리즘의 성능은 산업현장에서 사용되는 표준 부품을 임의로 겹치게하여 영상을 획득한 후 가리는 물체를 구분하는 실험을 통해 입증하였다.

• 벤처혁신연구
• /
• 제2권1호
• /
• pp.23-31
• /
• 2019

본 연구의 주요 목표는 업계에서 제품 안전에 기여하는 조직을 평가하고 선정하기 위한 적절한 지표를 개발하는 것이다. 제품 안전 지표는 제품 안전 활동 및 시스템의 순서에 입력, 프로세스 및 출력을 포함하며, 그 지표들은 측정 가능하고 측정 불가능한 지수의 측면에서 제안된다. 세부 지표는 제품 안전 관리, 제품 안전을 위한 노력, 제품 안전성능 등 3가지 부분으로 구성된다. 이 지표들은 시스템 및 제품 안전의 관리 능력의 차이로 인해 기업 규모(대, 중, 소)별로 항목별로 구분된다. 지표를 합리적으로 얻기 위해 산업분야의 전문가 의견과 VOC를 검토한다. 그리고 직급과 수준(간부 대 노동자)에 따라 구분한다. 지표의 항목은 20개, 점수는 200개로 어느 경우든 동일하다. 지표들은 그의 산업에서 제품 안전의 발전에 기여하는 인력을 선택하는데 유용한 도구로 사용할 수 있다.

• 한국환경과학회지
• /
• 제20권11호
• /
• pp.1395-1401
• /
• 2011

In this study, Life Cycle Assessment(LCA) has been carried out to evaluate the environmental impacts of a metallic can. A 360 mL volume of an aluminum can bottle was used as the functional unit. The results of Life Cycle Inventory(LCI) showed that iron ore and coal were the major parts of the input materials, whereas aluminum can products, carbon dioxide, wastewater, and hazardous wastes were those of the output ones. According to LCA weighting, it was observed that the most significant impact potential was found to be global warming(49.11%) followed by abiotic resource depletion(47.72%). In the whole system, cold rolled steel coil showed the largest environmental impact potential(86%), followed by electricity(14%). Meanwhile, lubricating oil and industrial water had the minor portion of the total environmental impact potentials. It was suggested that the use of cold rolled steel and electricity should be the main source for $CO_2$, resulting in the big impact on global warming.

• 한국유체기계학회 논문집
• /
• 제13권1호
• /
• pp.42-51
• /
• 2010

Many different types of fan have been applying to various industrial fields. Fan design methods are much different depending on the types of fan, operating conditions, and connecting parts at the inlet or exit of the fan etc. In this study, design methods for an axial-type suction fan are studied. This fan discharges the air in the relative static pressure of -285Pa to the atmosphere with the flow rate of $960m^3/min$. For three-dimensional blade design, three different design methods were applied, such as the free vortex method, the exponential method, and the cascade method. In the cascade method, the blade loading along the radial direction was obtained from the lift coefficient which was necessary to obtain the pressure rise on a fan rotor. This method is different from the free vortex and the exponential method which control the strength of the vortex. The fan performance prediction was conducted using the CFD with three different inlet ducts. The best fan performance was obtained when the fan was designed by using the cascade method. The designed fan using the exponential method showed better performance compared to a fan designed using the free vortex method. However, the fan performance was changed depending on the installed inlet ducts. So, an efficient fan can be designed with the adjustment of design variables on the basis of the flow structures within the fan as well as the fan design procedure.

• 한국해양공학회:학술대회논문집
• /
• 한국해양공학회 2004년도 학술대회지
• /
• pp.68-72
• /
• 2004

A practical method to investigate the user interface of web based Flexible Manufacturing System(FMS) on the internet environment is established. Because the industrial FMS controller requires a lot of gadget, such as switch, dial, button, etc., for actual work-site flexible operation sufficiently, the user interface of the controller is significantly complex. The support for operational convenience of FMS controller can increase productivity and efficiency of the user, operational personnel of FMS. While most FMS provide their application programming interface(API) and graphical user interface(GUI) with adequate mechanism itself when used in stand alone, there is increasing demand for FMS that can operate with the intuitional user interface find virtual reality(V/R) environment. This thesis considers the intuitional user interface of Web-based FMS first, and from this, goes a step further, improves as virtual reality environment of FMS on the internet environments by using the feature based modeling technique approach and cartoon rendering. The feature-based modeling technique approach is applied to FMS line which is consist of facilities such as machining center, CNC lathe, autonomous guided vehicle, rail guided vehicle, and various controllers. In this study, the FMS established the intuitional user interface is able to obtain not only the operational convenience but also the enough productivity and significant efficiency.

• 대한두개안면성형외과학회지
• /
• 제18권3호
• /
• pp.179-185
• /
• 2017

Background: The use of leeches can effectively increase the salvage rate of flap congestion. However, the first reaction from patients and carers in using leeches in clinical fields is strong aversion. This can be due to the fact that development of our culture from agriculture to industrial society, coming across leeches became fairly rare. Also because of the biological traits that leeches carry; staying attached to a leg or other body parts of the host, sucking blood, and leaving wounds. Methods: This study was conducted through questionnaires, divided into many subgroups. We scaled the compliance of the two therapies, with or without leech. Maximum scale of 10 showing no rejective response to the therapy and minimum scale of 0 showing the greatest rejective response. Results: Overall subjects' compliance was improved after explaining the benefits of hirudotherapy. Irrelevant to the explanation, there was no significant difference in general compliance between male and female. Young-aged group and medical personnel or people studying medicine showed higher compliance over older-aged group and the general public. Conclusion: In the terms of general social cognition, recognizing leech as a therapeutic material may not be welcomed at first, but provided with proper information and explanations, overall compliance of patients and carers can be improved and consequently result in superior outcomes in flap salvage.

• 한국세라믹학회지
• /
• 제43권12호
• /
• pp.823-828
• /
• 2006

One of the main issues of Solid Oxide Fuel Cells (SOFCs) is to reduce the operating temperature to $750^{\circ}C$ or less. It has advantages of improving the life of component parts and the long-term stability of a system, so the production cost could be decreased. In order to achieve that, the ohmic and polarization loss of a single cell should be minimized first. This paper presents.to fabricate anode-supported single cells with controlling microstructure as a function of particle size and volume of graphite and NiO-YSZ weight ratio. By means of optimizing the manufactural condition through microstructure analysis and performance evaluation, the single cell which had NiO-YSZ=6:4, graphite volume of 24% and graphite size of $75{\mu}m$ as the anode composition showed a distinguished power density of $510mW/cm^2$ at $650^{\circ}C$ and $810mW/cm^2$ at $700^{\circ}C$, respectively.