In this study, the regression equation was suggested to predict of the shot ball velocity according to blade shapes based on discrete element (DE) analysis. First, the flat type blade DE model was used in the analysis, the validity of the DE model was verified by giving that the velocity of the shot ball almost equal to the theoretical one. Next, the DE analyses for curved and combined blade models was accomplished, and their analytical velocities of shot ball were compared with the theoretical one. The velocity of combined blade model was greatest. From this, the regression equation for velocity of shot ball according to the blade shape based on the DE analysis was derived. Additionally, the wind speed measurement experiment was carried out, and the experimental result and analytical one were the same. Ultimately, it was confirmed that the prediction method of the velocity of shot ball based on DE analysis was effective.

이 논문은 잉카 쇼니바레의 《머리 없는 형상》 작업에 나타난 식민권력의 전복을 탈식민주의 이론 가 호미 바바의 ‘모방’ 개념을 통해 분석하였다. 쇼니바레는 유럽의 제국주의 침략이 극에 달한 18-19세기의 역사·문화를 패러디하고 식민지배자로 등장하는 인물의 머리를 자름으로써 권력의 불균형에 저항하고 인물에 식민사의 산물인 더치 왁스 천으로 만든 빅토리아 시대 의상을 입힘으로써 제국과 식민, 유럽과 아프리카 등의 이분법적 대립의 해체를 시도하였다. 그의 작품은 ‘거의 동일하지만 아주 똑같지는 않은’ 차이를 드러내는 피지배자의 과장된 모방을 통해 지배자의 정체성과 지배-피지배 구조를 위협한다. 또한 과거 제국주의와 식민주의의 역사를 피식민자의 관점에서 재구성하여 전 지구화 시대에도 끊임없이 반복되는 권력의 불균형에 대해 경고의 메시지를 던진다.

Effects of acid soaking (AS) and thermal sterilization (TS) on the shape and quality characteristics of Tteokbokki rice cake (TRC) were investigated. The F-value of a sequential process (SP) of the combination of AS and TS was quantitatively determined with a reference microorganism of Bacillus cereus. F-values were evaluated according to the minimum and the maximum D-value of B. cereus and the reduction exponent (m=12). The heat penetration curves at cold point (CP) of TRC (400 g) were used to estimate the TS time at 121, 100, and 95℃. F-values of the SP were revised according to the adjusted m values after AS at different pH. The non-uniformity parameters (NUP) of TRC had no significant changes during AS but it dramatically increased after applying TS at a low pH by AS. The result of solubilized starch contents (SSC) demonstrated that the shape changes during SP are related to SSC. The texture characteristics and the whiteness were significantly influenced by a low pH condition (3.5) (p<0.05). Sensory analysis showed that a lower pH and a longer thermal processing time influenced negatively on the acceptability. This study showed that pH 4.0 and 95℃ was an optimum condition for the SP.

Vortex tubes are simple tubes that can separate hot and cold air from compressed air without any internal device configuration and are used in many industries. If the vortex tube with these advantages is applied to an air conditioning system, it will be free from the use of refrigerant. In this study, basic study on discharge flow rate and temperature separation characteristics was carried out by varying the number of generator nozzle hole in various shapes of the vortex tube according to the inlet pressure of the vortex tube. Experimental results show that as the number of nozzles increases, the discharge flow rate tends to decrease and the temperature separation characteristics were excellent in the number of nozzles 6~7.

To study the effects of graphite shape and the composite fabricating method on the mechanical properties of graphite/copper (Gr/Cu) composites, a copper composite using graphite flakes or graphite granules as reinforcing phases is fabricated using mechanical mixing or electroless plating method. The mechanical properties of the Gr/Cu composites are evaluated by compression tests, and the compressive strength and elongation of the Gr/Cu composites using graphite granules as a reinforcing phase are compared with those of Cu composites with graphite flakes as a reinforcing phase. The compressive yield strength or maximum strength of the Gr/Cu composites with graphite granules as a reinforcing phase is higher than that of the composites using graphite flakes as a reinforcing phase regardless of the alignment of graphite. The strength of the composite produced by the electroless plating method is higher than that of the composite material produced by the conventional mechanical mixing method regardless of the shape of the graphite. Using graphite granules as a reinforcing phase instead of graphite flakes improves the strength and elongation of the Gr/Cu composites in all directions, and reduces the difference in strength or elongation according to the direction.

ZnO micro/nanocrystals are formed by a vapor transport method. Mixtures of ZnO and TiO powders are used as the source materials. The TiO powder acts as a reducing agent to reduce the ZnO to Zn and plays an important role in the formation of ZnO micro/nanocrystals. The vapor transport process is carried out in air at atmospheric pressure. When the weight ratios of TiO to ZnO in the source material are lower than 1:2, no ZnO micro/nanocrystals are formed. However, when the ratios of TiO to ZnO in the source material are greater than 1:1, the ZnO crystals with one-dimensional wire morphology are formed. In the room temperature cathodoluminescence spectra of all the products, a strong ultraviolet emission centered at 380 nm is observed. As the ratio of TiO to ZnO in the source material increases from 1:2 to 1:1, the intensity ratio of ultraviolet to visible emission increases, suggesting that the crystallinity of the ZnO crystals is improved. Only the ultraviolet emission is observed for the ZnO crystals prepared using the source material with a TiO/ZnO ratio of 2:1.

ZnO crystals with different morphologies are synthesized through thermal evaporation of the mixture of Zn and Cu powder in air at atmospheric pressure. ZnO crystals with wire shape are synthesized when the process is performed at 1,000 oC, while tetrapod-shaped ZnO crystals begin to form at 1,100 oC. The wire-shaped ZnO crystals form even at 1,000 oC, indicating that Cu acts as a reducing agent. As the temperature increases to 1,200 oC, a large quantity of tetrapod-shaped ZnO crystals form and their size also increases. In addition to the tetrapods, rod-shaped ZnO crystals are observed. The atomic ratio of Zn and O in the ZnO crystals is approximately 1:1 with an increasing process temperature from 1,000 oC to 1,200 oC. For the ZnO crystals synthesized at 1,000 oC, no luminescence spectrum is observed. A weak visible luminescence is detected for the ZnO crystals prepared at 1,100 oC. Ultraviolet and visible luminescence peaks with strong intensities are observed in the luminescence spectrum of the ZnO crystals formed at 1,200 oC.

In the present study, we develop a conductive copper/carbon nanomaterial additive and investigate the effects of the morphologies of the carbon nanomaterials on the conductivities of composites containing the additive. The conductive additive is prepared by mechanically milling copper powder with carbon nanomaterials, namely, multi-walled carbon nanotubes (MWCNTs) and/or few-layer graphene (FLG). During the milling process, the carbon nanomaterials are partially embedded in the surfaces of the copper powder, such that electrically conductive pathways are formed when the powder is used in an epoxy-based composite. The conductivities of the composites increase with the volume of the carbon nanomaterial. For a constant volume of carbon nanomaterial, the FLG is observed to provide more conducting pathways than the MWCNTs, although the optimum conductivity is obtained when a mixture of FLG and MWCNTs is used.

Recently, as the complexity of system becomes increased, it becomes important to manage, track, and control the configuration information of various assets of complex systems such as plant and factory over system lifecycle. We call it configuration management (CM). CM enables us to establish and maintain the consistency of a system’s functional and physical attributes with its design requirements, and operational information throughout its lifecycle. In this study, we look through the main concept of CM and relevant research works. Also, we address the CM processes suitable to small-and-medium sized plant in terms of modeling viewpoint.

본 논문의 목적은 투르게네프의 『사냥꾼의 수기』에 수록된 25편의 작품 중농노들의 이야기를 다룬 여섯 작품을 선별하여 농민들의 삶 속에 형상화된 자유의 의미를 분석하는 데 있다. 투르게네프는 벨린스키의 사망과 프랑스 혁명의 실패가 있었던 1848년을 기점으로 ‘주인과 하인’의 문제에서 삶과 관련된 존재론적 문제로 사유의 폭을 확장하였다. 따라서 자유에 관한 그의 사유도 일정한 변화를 겪게 된다. 우선 투르게네프는 자연과 문명이라는 두 대비적 공간 속에서 존재를 구속하는 문명의 모든 일체에서 벗어나 자연스러운 삶을 동경하고 향유하는 것이 참된 자유라 생각했다. 그러기 위해서 투르게네프는 ‘무엇으로부터의 자유’라는 자유의 일반개념에서 ‘무엇’이라는 대상성 자체에서 벗어나 존재 내면에서 약동하는 ‘자연’과 교감할 것을 강조한다. 자유에 관한 투르게네프의 생각은 1848년 이후 죽음과 운명의 문제와 결합하면서 변화를 겪게 된다. 그것은 운명에 대한 맹목적인 수용이 아니라, 루케리아처럼 신의 섭리를 주체적으로 깨닫고 자신의 운명을 자기 긍정의 힘으로 사유하는 것을 의미했다. 이렇듯 본 논문에서는 『사냥꾼의 수기』에 형상화된 자유의 의미를 다층적으로 살펴보았다.

니티놀이라고 하는 니켈-티타늄 형태의 형상기억 합금(SMA)은 상당한 양의 변형이 발생한 후에 추가적인 열을 가하지 않더라도 상온에서 원래 모양으로 복원될 수 있는 초탄성 효과를 가진다. 이러한 독특한 재료 특성 때문에, 니티놀은은 의료, 전기, 전자 및 기계 분야뿐만 아니라 토목 공학 분야의 내진 개량을 위한 변위 제어 장치로 널리 사용되어 왔다. 탄소강과 달리 초탄성 형상기억합금은 피로 저항성이 강하며 하중 속도에 따라 강성(하중-변위특성)등의 기계적 물성치가 변화한다. 본 연구에서는 하중 사이클의 반복 횟수와 속도에 따라 초탄성 형상기억합금의 기계적 물성치가 어떻게 변하는가에 대한 실험적 연구를 수행하였다. 본 연구로 인해 표준화된 초탄성 형상기억합금의 기계적 물성치는 이후 초탄성 형상기억합금을 적용한 내진 장치의 설계과정에서 활용함으로써 설계 효율성을 높일 수 있을 것으로 기대된다.

이 논문의 목적은 편양 언기(1581∼1644)의 선사상 특징과 그것이 구도와 깨달음을 얻어가는 과정, 깨달음을 증득한 후의 보림(保任), 자연교감과 방외(方外)의 생활과 대중교화에 있어 어떻게 투영, 시적 형상화되고 있는가를 살펴보는 데 있다. 언기는 교와 선을 별문(別門)으로 보지 않는 서산 휴정(西山休靜)의 사상을 계승하고 있다. 언기의 선사상의 핵심은, 선은 교외별전의 경절문이며, 선교일치의 사상을 보이면서 선을 교보다 우위에 둔 점, 깨달음에 이르는 문을 경절문, 원돈문, 염불문 등의 삼문으로 구분한 점, 그리고 그 삼문은 방법의 차이가 있을 뿐 모두 자성을 밝히기 위한 것으로 궁극적인 경지는 같다는 것이다. 언기는 서산의 ‘4대 문파’ 가운데 최대 계파로 조선 후기 불교교단의 대중화에 중요한 역할을 하였다. 그는 자신의 득도와 참선 수행에만 전념하지 않고, 10여 년간 평양성 근처에서 양을 치고 걸인들을 보살피는 등 중생의 아픔을 함께 나눈 철저한 보살행을 실천했다. 그의 「편양당집」에 수록된 시들은 구도의 과정과 깨달음을 노래한 시, 산승으로 살아가며 느끼는 자연과의 감회를 읊은 시, 찾아오는 속인들을 향해 읊은 시, 도반의 선승들에게 준시 등으로 구성되어 있다. 그의 이러한 시문은 치열한 구도와 깨달음을 향 한 수행과 대중교화에 진력한 모습을 잘 보여준다. 여기에는 선심(禪心)의 시심화(詩心化)가 잘 담겨져 있음을 알 수 있다.

본 연구에서는 DVR 내부 공기유동을 직접 제어하여 CPU의 온도를 낮추기 위한 유동제어 구조물을 제안하였다. 제안된 구조물은 세 개의 얇은 판의 형태로 구성되었으며, DVR 내부의 공기 유동을 포괄적으로 제어하여 CPU의 효율적인 방열을 유도하고자 하였다. DOE와 RSM을 이용한 매개변수 연구기법을 통해 유동제어 구조물의 형상을 최적화하였으며, 해석에는 유한체적방법을 이용한 유체역학 분석 패키지인 FlowVision을 사용하였다. 실제 DVR 기기에서의 실험을 통해 해석 결과를 검증한 결과 CPU의 온도가 16.1℃ 낮아짐을 확인하였다

In this study, high thermal efficiency and eco-friendly coffee roaster is developed. The core element of coffee roaster is a roasting drum and most of the coffee roasting drum is a flat cylindrical barrel type. From the traditional shape of cereal puffing machine, we got the idea of the roasting drum. Oak barrel shape is well known high thermal efficiency system in korean heating cook system. Therefore, we designed the coffee roaster containing the oak barrel shaped drum and combustor nozzles which has an ability of roasting 3kg of coffee beans within 10 minutes of roasting time. With our developed coffee roasting machine, the heating speed of roasting process is very fast, and the roasting of coffee beans can be quickly finished. We experimented the roasting time and compared the results with other coffee roasting machines of the same amount of roasting capacity. The results were outstanding in roasting time and the quality of roasting. In spite of smaller fuel consumption, the roasting time was more shorter than flat cylindrical roasting drum.

A micromixer is a component of a lab-on-a-chip or microfluidic device that mixes two or more chemicals together. The purpose of this study is to assess the performance of passive micromixer of various shapes. Six shapes of micromixers compared mixing performance. Three dimensional modeling was carried out to have the same hydraulic diameter. The commercial code, ANSYS Fluent, was used to simulate the internal mixing flow. A numerical analysis method is described in detail in this paper. The performance of the micromixer was compared with the mixing index and pressure drop. Consequently, the CDM-8T shape showed reasonable mixing performance and relatively low pressure drop.