Research is being actively conducted on the continuous thin plate casting method, which is used to manufacture magnesium alloy plate for plastic processing. This study applied a heat transfer solidification analysis method to the melt drag process. The heat transfer coefficient between the molten magnesium alloy metal and the roll in the thin plate manufacturing process using the melt drag method has not been clearly established until now, and the results were used to determine the temperature change. The estimated heat transfer coefficient for a roll speed of 30 m/min was 1.33 × 105 W/m2·K, which was very large compared to the heat transfer coefficient used in the solidification analysis of general aluminum castings. The heat transfer coefficient between the molten metal and the roll estimated in the range of the roll speed of 5 to 90 m/min was 1.42 × 105 to 8.95 × 104 W/m2·K. The cooling rate was calculated using a method based on the results of deriving the temperature change of the molten metal and the roll, using the estimated heat transfer coefficient. The DAS was estimated from the relationship between the cooling rate and DAS, and compared with the experimental value. When the magnesium alloy is manufactured by the melt drag method, the cooling rate of the thin plate is in the range of about 1.4 × 103 to 1.0 × 104 K/s.

The purpose of this study is to improve the mechanical properties and develop manufacturing technology through self-soluble alloy powder flame spray coating on the surface of a run-out table roller for hot rolling. The roller surface of the run-out table should maintain high hardness at high temperatures and possess high wear, corrosion, and heat resistances. In addition, sufficient bonding strength between the thermal spray coating layer and base material, which would prevent the peel-off of the coating layer, is also an important factor. In this study, the most suitable powder and process for roll manufacturing technology are determined through the initial selection of commercial alloy powder for roll manufacturing, hardness, component analysis, and bond strength analysis of the powder and thermal spray coating layer according to the powder.

Al-Cr-Si ternary quench ribbons are fabricated using a single roll method and investigated for their structural and thermal properties. In particular, the sinterability is examined by pulse current sintering to obtain the following results. The Al74Cr20Si6 composition becomes a quasicrystalline single phase; by reducing the amount of Cr, it becomes a twophase mixed structure of Al phase and quasicrystalline phase. As a result of sintering of Al74Cr20Si6, Al77Cr13Si10 and Al90Cr6Si4 compositions, the sintering density is increased with the large amount of Al phase; the sintering density is the highest in Al90Cr6Si4 composition. In addition, as a result of investigating the effects of sintering temperature and pressurization on the sintered density of Al90Cr6Si4, a sintered compact of 99% or more at 513 K and 500 MPa is produced. In particular, since the Al-Cr-Si ternary crystal is more thermally stable than the Al-Cr binary quaternary crystal, it is possible to increase the sintering temperature by about 100 K. Therefore, using an alloy of Al90Cr6Si4 composition, a sintered compact having a sintered density of 99 % or more at 613 K and 250 MPa can be manufactured. It is possible to increase the sintering temperature by using the alloy system as a ternary system. As a result, it is possible to produce a sintered body with higher density than that possible using the binary system, and at half the pressure compared with the conventional Al-Cr binary system.

이 논문은 예이츠의 희곡 『큰 시계탑의 왕』의 타이틀 롤을 맡고 있는 큰 시계탑의 왕에 관한 연구이다. 『큰 시계탑의 왕』은 수정과 발전을 거듭하는 과정에서 극의 제목이 『삼월의 보름달』로 바뀌게 되고, 새로운 제목의 버전에서는 원래 버전에서 타이틀 롤인 왕은 사라지게 되었다. 하지만 새로운 버전에서 그 인물이 생략되었다는 것이 원래 버전에서 담당하고 있던 인물의 기능을 모두 무의미한 것으로 평가하는 것은 아니기 때문에, 이 논문은 큰 시계탑의 왕에 주목하여 극을 면밀히 분석함으로써 그가 수행하고 있는 여러 기능을 탐구한다. 먼저 『큰 시계탑의 왕』이라는 제목이 암시해주는 것처럼 왕은 시간을 상징하는 인물이다. 하지만 이러한 상징적 의미뿐 아니라 이 희곡의 구조적 원형이 되고 있는 『매의 우물에서』의 노인과 같이 주인공과 대비되는 역할을 하고 있음을 증명하고, 더 나아가 극의 행위가 진행될 수 있도록 하는 촉발자와 극의 극적 긴장감을 조성하는 역할을 하고 있음을 보여준다. 결론으로서 왕의 존재가 이 희곡을 『삼월의 보름달』과 차별화하는 데 중요한 요소가 된다는 것을 주장한다.

처분 부적합 폐기물이란 원전운영이나 해체 시 처리, 고화 및 포장이 요구되는 방사성폐기물 등을 일컬으며, 대표적으로 분산 특성을 갖는 입자성 방사성폐기물을 예로 들 수가 있다. 이들 폐기물에는 원전 운영과정에서 발생되는 농축폐액의 건조 분말, 슬러리 및 슬러지, 향후 원전 해체과정에서 발생되는 온갖 분말 상태의 폐기물(콘크리트 파쇄물, 제염 슬러지 등), 그리고 제염이 용이치 못한 미세 크기의 방사능오염 토양 등이 있다. 입자성 폐기물을 기존의 고화방식으로 처리할 경우에는 최종 폐기물의 부피가 증가하는 단점을 갖게 되어 처분 비용의 증가 및 처분장의 수용성을 감소하는 결과를 야기할 수가 있 다. 따라서 이들 문제를 해결하고자 본 연구에서는 최종 폐기물 부피의 감용화를 위해 롤 압축 기술을 이용하여 분말의 펠렛화 연구를 수행하였다.

The aim of the present work was to develop simultaneous methods of quantification of carazolol, azaperone, and azaperol residues in livestock and fishery products using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Samples were extracted from beef, pork, chicken, egg, milk and shrimp using acetonitrile (ACN); while flat fish and eel were extracted using 80% ACN. For purification, ACN saturated n-hexane was used to remove fat composition. The standard calibration curves showed good linearity as correlation coefficients; r 2 was > 0.99. Average recoveries expressed were within the range of 67.9-105% for samples fortified at three different levels (0.5 × MRL, 1 × MRL and 2 × MRL). The correlation coefficient expressed as precision was within the range of 0.55- 7.93%. The limit of quantification (LOQ) was 0.0002-0.002 mg/kg. The proposed analytical method showed high accuracy and acceptable sensitivity based on Codex guideline requirements (CAC/GL71-2009). This method can be used to analyze the residue of carazolol, azaperone, and azaperol in livestock and fishery products.

SUS hexagonal bar, which is manufactured by drawing process of SUS circular bar, have been widely used to make various adapters and fittings. The purpose of this study is to investigate the characteristics and stability of variable roll unit including stand module. Stand module is essential part of variable roll unit. Structural analysis was performed to predict the stability of stand module using 3 loads (50, 75, 100 Ton), thus it may be of help to the manufacture of stand module. As the results, internal ring of bearing showed maximum equivalent stress, and moreover bearing, shaft and roller had to be preferentially considered in order to maintain its stability. In cases of 50 and 75 Ton, there were no problems for stabilities, respectively, on the other hand, problem for stability may occur in case of 100 Ton.

Wire rods having various sectional shape are generally used directly in various applications. In the shape rolling, a couple of grooved rollers are used and the groove match the sectional shape of the wire rod. In this 2 roll system, a couple of rollers must be changed whenever the sectional shape of the wire rod is changed, and the frequent changes of roller cause rise of manufacturing cost. We developed a 4 roll wire rolling mill that reduce the disadvantage of 2 roll rolling, at the same time improving quality of the wire rods and reducing production costs. The present work is focused on the development of a high precision 4 roll wire rolling mill for the wire rods that have various rectangle sectional shape.

본 연구는 수형자가 주체적⋅자발적으로 참여할 수 있는 교육프로그램을 개발하여 그 효과를 밝히는 것을 목적으로 하였다. 주요 교육방법으로는 시청각교육과 그룹워크를 가미한 일본의 롤레터링 기법을 채택하였고, 총12회기의 프로그램을 구성하여 Z교도소 수형자를 대상으로 교육을 실시하였다. 제1기(12명)는 2015년 1월부터 4월까지, 그리고 제2기(13명)는 동년 5월부터 8월까지 프로그램을 진행하였고, 교육 전후의 자아존중감, 공감능력, 분노 그리고 충동성의 변화를 살펴보았다. 결과분석에는 SPSS ver.23 통계프로그램을 사용하였다. 분석결과, 본 교육프로그램의 실시 후에 수형자의 자아존중감과 공감능력은 향상되고 충동성은 저하되는 등 통계적으로 유의미한 변화가 있음을 확인할 수 있었다. 이와 같은 결과는, 롤레터링 기법을 활용한 본 교육프로그램이 수형자의 수용생활을 긍정적인 방향으로 변화시키고, 출소 후 재범을 방지하는 효과적인 방법이 될 수 있음을 시사한다. 아울러 분노의 양상은 제1기에서는 유의미한 변화가 있었지만 제2기에서는 눈에 띄는 변화가 없었는데, 이것은 수형자의 형기, 죄명, 연령 등 그룹구성원의 속성에 따라 다양한 결과가 도출될 수 있음을 시사한다.

As film products are increasingly used in a wide range of areas, from producing traditional flexible packaging to high-tech electronic products, a higher level of quality is demanded. Most film products are made in the form of rolled finished goods, therefore, various quality issues related to their shape characteristics must be addressed. The thickness of the film products is one of the most common and important critical-to-quality attributes (CTQs). Particularly, the degree of thickness uniformity is more important than other thickness parameters, because it will be potential causes of many secondary thickness-related quality problems, such as wrinkles or faulty windings. To control the degree of thickness uniformity, the fixed bending region is oneof the most important CTQs to manage. Fixed bending regions are special points in the transverse direction of a rolled product with consistent minute variations of the thickness gap. This paper describes the measurement and analysis of thickness uniformity data, which were performed in a real manufacturing field of biaxial oriented polypropylene (BOPP) film. In previous researches, quality function deployment (QFD) or fault tree analysis were used to find the most critical process attributes out to controlthe CTQ of thickness uniformity. Whereas, this paper uses traditional control charts to find the most critical process attributes out in this problem. In addition, the selection of one of the major critical process attributes (CTPs) that is expected to affect the CTQ of thickness uniformity is also described. The selected critical-to-process attributes are the controlled temperatures along the transverse direction. A dramatic improvement in thickness uniformity was observed when the selected CTPs were controlled.

2013년부터 2014년 부여의 무농약 양송이버섯 재배농가에서 포식성 천적(제품명: 마일즈응애, 종명: Stratiolaelaps scimitus), 백색 LED 및 황색 롤트랩을 이용하여 버섯파리의 밀도감소 효과와 양송이 생산량에 미치는 영향을 조사하였다. 백색 LED(1.3×5m)는 1동 당 165㎡의 양송이버섯 재배사 양측면 벽면과 균상 위 베드 2단과 3단 사이의 높이에 설치하였다. 황색 롤트랩(폭 20cm)은 LED 아래 벽면에 부착하고, 롤트랩만 설치하는 구는 양측면에 한 줄씩 설치하였다. 그리고 마일즈응애는 165㎡ 당 20,000 마리(2통)를 균상 위에 골고루 흩어 뿌렸다. 마일즈응애는 작기마다 종균 접종 후, 복토 후, 1주기 시작 시에 각각 1회, 2회, 3회 방사하였다. 각 처리마다 백색 LED, 황색 롤트랩 및 포식성 천적을 처리한 후 양송이버섯의 생산량을 조사하였다. 그 결과, 관행구 대비 소득증가율은 LED를 설치하지 않을 경우 소득이 감소하는 것으로 나타났다. 그러나 LED+롤트랩+포식성 천적을 종합 사용 할 경우에는 모두 소득이 증가하였으며, 특히 LED+롤트랩+포식성 천적 3회방사구에서는 관행구 대비 16.9∼19.1%의 소득증가율을 보였다. 무처리구 대비 소득증가율은 롤트랩만 설치할 경우에는 무처리와 소득이 비슷했으나, 그 외의 모든 처리구에서 소득이 증가하였다. LED+롤트랩+포식성 천적 3회방사구는 무처리 대비 소득증가율이 45.7∼48.4%에 이르는 것으로 나타났다. 균상 위에 LED를 설치할 경우 관행구나 무처리에 비해 소득이 크게 증가하지만 측면 LED 설치구에서 소득 증가율이 더 높았으며, 균상 위에 LED를 설치하면 버섯파리의 성충 유인효과는 크지만 균상에 알을 낳는 경우가 발생하였다. 또한 작업에 불편을 끼치며 벽면보다 설치비용이 많이 소요되어 LED는 벽면에 설치하는 것이 효율적이었다.

롤 투 플레이트 시스템은 인쇄 전자에서 가장 경제적이고 효과적인 방법 중 하나이다. 본 논문에서는 롤 투 플레이트 시스템의 틈새출구에서 PDMS의 공동 변화가 유체 흐름의 어떠한 영향을 미치는지, 또 플레이트에 어떻게 전이되는가를 시뮬레이션을 통해 규명하였다. 실험은 IGT-C1 인쇄적성 실험기를 이용하여 전이율, 인쇄 밀도, 프린트 스루, 분할점 등과 같은 데이터를 측정하여, 컴퓨터 시뮬레이션 결과 값들과 비교 분석하였다. 컴퓨터 시뮬레이션은 Flow 모델을 뉴토니언 모델로 생성하여, Navier-Stokes 방정식을 기반으로 한 패키지 소프트웨어인 Polyflow와 Flow 3D로 시뮬레이션 하였고, 시뮬레이션 결과와 실험 결과는 잘 일치하였다.

As film products are more frequently used from producing traditional flexible packing products to high-tech electronic products, requested higher level of quality. Most film products are made in the shape of roll-type finished goods, so various quality problems are addressed related with their characteristics of shape. Thickness of film products is one of the most common and important quality problems. Particularly the Degree of thick smoothness is more important than other thickness issues, because it causes many secondary issues of thickness-related quality problems like wrinkles or faulty windings. Thick smoothness must be controlled in both horizontal and vertical direction. In this paper, HOQ (house of quality) was built to interpret VOC (voice of customers) to CTQs (critical to quality). To decide priorities of VOC and CTQs, both techniques are applied. One is AHP (analytic hierarchy process) with pairwise comparison. The other is an absolute weight calculation method with level-up rate. From the result of HOQ, it is certain that the thick smoothness is the most important CTQ in film manufacturing industry. Finally, this paper presents how to monitor and improve repetitive coincidence of microscopic deviation of thickness in some special vertical points.

This study evaluated the enhancement of microstructural and mechanical properties of a cross rolled Ni-10Cr alloy, comparing with conventionally rolled material. Cold rolling was carried out to 90% thickness reduction and the specimens were subsequently annealed at 700˚C for 30 min to obtain a fully recrystallized microstructure. Cross roll rolling was carried out at a tilted roll mill condition of 5˚ from the transverse direction in the RD-TD plane. In order to observe the deformed microstructures of the cold rolled materials, transmission electron microscopy was employed. For annealed materials after rolling, in order to investigate the grain boundary characteristic distributions, an electron back-scattering diffraction technique was applied. Application of cold rolling to the Ni-10Cr alloy contributed to notable grain refinement, and consequently the average grain size was refined from 135 μm in the initial material to 9.4 and 4.2 μm in conventionally rolled and cross rolled materials, respectively, thus showing more significantly refined grains in the cross rolled material. This refined grain size led to enhanced mechanical properties such as yield and tensile strengths, with slightly higher values in the cross rolled material. Furthermore, the<111>//ND texture in the CRR material was better developed compared to that of the CR material, which contributed to enhanced mechanical properties and formability.

We carried out this study to evaluate the grain refining in and the mechanical properties of alloys that undergo severe plastic deformation (SPD). Conventional rolling (CR) and cross-roll rolling (CRR) as SPD methods were used with Ni-20Cr alloy as the experimental material. The materials were cold rolled to a thickness reduction of 90% and subsequently annealed at 700˚C for 30 min to obtain a fully recrystallized microstructure. For the annealed materials after the cold rolling, electron back-scattered diffraction (EBSD) analysis was carried out to investigate the grain boundary characteristic distributions (GBCDs). The CRR process was more effective when used to develop the grain refinement relative to the CR process; as a result, the grain size was refined from 70μm in the initial material to 4.2μm (CR) and 2.4μm (CRR). These grain refinements have a direct effect on improving the mechanical properties; in this case, the microhardness, yield and tensile strength showed significant increases compared to the initial material. In particular, the CRR-processed material showed more effective values relative to the CR-processed materials. The different texture distributions in the CR (001//ND) and CRR (111//ND) were likely the cause of the increase in the mechanical properties. These findings suggest that CRR can result in materials with a smaller grain size, improved texture development and improved mechanical properties after recrystallization by a subsequent annealing process.

The objective of this study was to assess the physicochemical characteristics of morning rolls containing various levels (0, 2, and 4%) of Makgeolli lees extract powder, which has nutritional and health effects. The results demonstrated that pH, moisture content, volume, weight, and baking loss rate of morning rolls were not significantly different among the groups. In the morning rolls with 4% Makgeolli lees extract powder, the Hunter's color 'a' (redness), but not L (lightness) or b (yellowness), was significantly higher than that in the other two groups. After estimating the texture quality of morning rolls, hardness, chewiness, and gumminess decreased significantly with added Makgeolli lees extract powder, but springiness was not significantly different. The results of the sensory test showed that appearance and texture increased as more Makgeolli lees extract powder was added, and that the overall acceptability score and air cell uniformity score for 2% and 4% Makgeolli lees extract powder morning rolls were significantly higher than those of controls. These results indicate that the texture and sensitivity of morning rolls can be increased by adding Makgeolli lees extract powder without affecting the overall quality.