• 한국식품과학회지
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• 제25권4호
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• pp.355-359
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• 1993

명반이 멥쌀과 찹쌀전분의 이화학적 성질에 미치는 영향을 조사하였다. 멥쌀 및 찹쌀전분의 팽윤력은 두 전분 모두 대조구보다 명반 $0.05{\sim}1.0%(w/w)$ 첨가구에서 증가하였으며, 이 농도 이상에서는 완만하게 감소하는 경향을 나타내었다. 용해도는 멥쌀전분의 경우 명반 $0.05{\sim}1.0%(w/w)$ 첨가구에서는 온도증가에 따라 점차 증가한 반면, 찹쌀전분의 경우는 온도에 관계없이 감소하였으며, 이농도 이상에서는 두 전분 모두 거의 변화를 보이지 않았다. Blue value값은 명반농도가 증가할수록 멥쌀전분의 경우는 증가한 반면, 찹쌀전분에서는 감소하였다. Amylography에 의한 호화양상에 있어서는 명반 1.0%(w/w) 첨가가 멥쌀 및 찹쌀전분의 호화개시 온도와 breakdown값을 증가시켰고 setback값은 감소시켰다.

• 한국세라믹학회지
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• 제51권3호
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• pp.170-176
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• 2014

Effective glass frit compositions enabled to absorb laser energy, and to seal a commercial dye-sensitized solar-cell-panel substrate were developed by using $V_2O_5$-based glasses with various amounts of $TeO_2$ substitution. The latter was intended to increase the lifetime of the solar cells. Substitution of $V_2O_5$ by $TeO_2$ provided a strong network structure for the glasses via the formation of tetrahedral pyramids in the glass, and changed the various glass properties, such as glass transition temperature ($T_g$), dilatometric softening point ($T_d$), crystallization temperature, coefficient of thermal expansion (CTE), and glass flowage without any detrimental effect on the laser absorption property of the glasses. The thermal expansion mismatch (${\Delta}{\alpha}$) between the glass frit and the substrate could be controlled within less than ${\pm}5%$ by addition of 10 wt% of ${\beta}$-eucryptite. An 810 nm diode laser was used for the sealing test. The laser sealing test revealed that the VZBT20 glass frit with 10 wt% ${\beta}$-eucryptite was successfully sealed the substrates without interfacial cracks and pores. The optimum sealing conditions were provided by a beam size of 3 mm, laser power of 40 watt, scan speed of 300 mm/s, and 200 irradiation cycles.

• 제어로봇시스템학회논문지
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• 제8권1호
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• pp.21-27
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• 2002

Inspection and shape measurement of three-dimensional objects are widely needed in industries for quality monitoring and control. A number of visual or optical technologies have been successfully applied to measure three-dimensional surfaces. However, those conventional visual or optical methods have inherent shortcomings such as occlusion and variant surface reflection. X-ray vision system can be a good solution to these conventional problems, since we can extract the volume information including both the surface geometry and the inner structure of any objects. In the x-ray system, the surface condition of an object, whether it is lambertian or specular, does not affect the inherent characteristics of its x-ray images. In this paper, we propose a three-dimensional x-ray imaging method to reconstruct a three dimensional structure of an object out of two dimensional x-ray image sets. To achieve this by the proposed method, two or more x-ray images projected from different views are needed. Once these images are acquired, the simultaneous algebraic reconstruction technique(SART) is usually utilized. Since the existing SART algorithms have several shortcomings such as low performance in convergence and different convergence within the reconstruction volume of interest, an advanced SART algorithm named as USART(uniform SART) is proposed to avoid such shortcomings and improve the reconstruction performance. Because, each voxel within the volume is equally weighted to update instantaneous value of its internal density, it can achieve uniform convergence property of the reconstructed volume. The algorithm is simulated on various shapes of objects such as a pyramid, a hemisphere and a BGA model. Based on simulation results the performance of the proposed method is compared with that of the conventional SART method.

• 산업경영시스템학회지
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• 제40권2호
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• pp.22-30
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• 2017

PL (Product Liability) refers to the legal responsibility of a manufacturer or seller for bodily injuries or property losses caused by product defects. Therefore, it is important for companies to construct a product liability response system that strategically manage and effectively adapt to product liability. A PL response system refers to companywide operations of PL prevention (PLP) measures, product safety (PS) measures, and PL defense (PLD) measures appropriate for a company's scale and environment. To establish an enterprise product liability response system, each essential component of corporations should be systematically operated and maintained considering the scale and characteristics of the corporations. Essential components of PL response system is Strategy, Organization, Training, Technology, Investment, and Awareness. Role of essential components is that companies need specific strategies to secure product safety and protect customers from product defects, and appropriate organizations must be composed for effective operation of such strategies. The objective of this paper seeks to examine the relationships among the essential components of the product liability response system and PL performance. PL performance consists of positive performance and negative performance. In particular, positive performance include increased efforts in product or process innovation such as strengthening research and development (R&D) to produce safer products without defects. In order to carry out this research we obtained 98 questionnaire of manufacturing company. A summary of the analyses is as follows: First, the awareness and technology among essential components affect significantly to the positive performance. Second, the awareness and strategy among essential components negative affect to the negative performance.

• 접착 및 계면
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• 제14권2호
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• pp.82-87
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• 2013

본 연구에서는 레졸, 질산철 그리고 트리블럭 공중합체를 이용하여 직접 탄화과정에 의해 자성체 나노입자가 분산된 탄소나노세공체를 합성하였다. 나노세공 마그네타이트/카본($Fe_3O_4$/carbon) 나노복합체는 낮은 마그네타이트 함량(1 wt%)을 가지고 잘 배열된 이차원적 육방체 구조(p6mm)를 보이며, 균일한 세공크기(3.6 nm), 높은 표면적(635 $m^2/g$)과 세공부피(0.48 $cm^3/g$)를 가진다. 작은 입자크기(10.2 nm)를 가지는 마그네타이트 나노입자는 초상자기성(7.7 emu/g)을 보이고 탄소 세공벽 내에 잘 분산되었다. 나노세공 마그네타이트/카본 물질은 최대 995 mg/g의 아이부프로펜 흡착량을 보였다. 또한, 자석을 이용하여 용액과 나노세공 마그네타이트/카본 물질의 분리가 용이하였다. 본 연구에서 제조된 나노복합체는 우수한 아이부프로펜 흡착제로 작용하였다.

• 한국초전도ㆍ저온공학회논문지
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• 제19권3호
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• pp.27-32
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• 2017

The effects of artificial holes on the trapped magnetic fields and magnetic levitation forces of very large single-grain $Y_{1.5}Ba_2Cu_3O_{7-y}$ (Y1.5) bulk superconductors were studied. Artificial holes were made for Y1.5 powder compacts by die pressing using cylindrical dies with a diameter of 30 mm or 40 m, or rectangular dies with a side length of 50 mm. The single grain Y1.5 bulk superconductors (25 mm, 33 mm in diameter and 42 mm in side length) with artificial holes were fabricated using a top-seeded melt growth (TSMG) process for the die-pressed Y1.5 powder compacts. The magnetic levitation forces at 77 K of the 25 mm single grain Y1.5 samples with one (diameters of 4.2 mm) or six artificial holes (diameters of 2.5 mm) were 10-17% higher than that of the Y1.5 sample without artificial holes. The trapped magnetic fields at 77 K of the Y1.5 samples with artificial holes were also 9.6-18% higher than that of the Y1.5 sample without artificial holes. The 33 mm and 42 mm single grain Y1.5 samples with artificial holes (2.5 mm and 4.2 mm in diameter) also showed trapped magnetic fields 10-13% higher than that of the Y1.5 samples without artificial holes in spite of the reduced superconducting volume fraction due to the presence of artificial holes. The property enhancement in the large single grain Y1.5 bulk superconductors appears to be attributed to the formation of the pore-free regions near the artificial holes and the homogeneous oxygen distribution in the large Y123 grains.

• 한국의류산업학회지
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• 제5권3호
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• pp.267-272
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• 2003

Tactel(Nylon66) union fabrics were woven with the specification of 70d/34f nylon as warp for sport wear jacket. Weft yarn has three types; 100% cotton yarn, nylon core-spun yarn and nylon-polyurethane covering yarn as weft. Fabric structers were plain, twill and satin weave structure with the air jet loom. The mechanical properties of 8 fabrics were measured with KES-F and primary Hand Values and Total Hand Values were calculated. The results of the study were as follows: 1) There was little difference among LTs of N/CM fabric groups. RT of the fabrics with CM100's was bigger than that of fabrics with CM80's, resulting that the fabrics with CM100's have better formability. In terms of weaving structure, twill fabrics have shape deformation. 2) In comparison of RTs with weft yarn type, RT of N-PU covering yarn was the highest, followed by Nylon core-spun yarn and cotton yarn. Thus, the fabric with N-PU covering yarn has better stability of shape deformation. 3) Stretch yarn could express an excellent silhouette formation and twill and satin structures were better structure to make curvature on human form. 4) 2HG/G value of nylon core-spun fabrics was larger than that of N/C fabrics, but the silhouette formation of N/C fabrics was excellent. 5) The RC of N/PU was the highest, followed by N/P, and N/CM. 6) Koski of N/PU fabrics was the highest, Numeri of N/PU and N/Co-I were relatively higher than the others. THVs of N/CM-IV and N/CO-II were lower than the others, resulting that, twill structure was better than plain structure for a sport wear uses.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제31권2호
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• pp.127-135
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• 2009

Objectives : The titanium fixation system has been used in orthognathic surgery for fixation of bone segments usually, but the biodegradable fixation system was developed and also being used. The strongest point in the biodegradable system is that no extra operation should be needed to remove fixation materials. In spite of this merit, oral & maxillofacial surgeons hesitate to use this system in fracture or orthognathic surgery. In this study, as we got some clinical experiences, we'd like to report the result of clinical study using the biodegradable fixation system in orthognathic surgery. Patients and Methods : A total of 35 patients composed of 17 males and 18 females with 25 osteotomies in maxilla and 34 osteotomies in mandible were fixated with the biodegradable fixation system(Inion $CPS^{(R)}$). We investigated methods of stabilization, fixation time, and complications on the basis of the method as above. Results : Four 2mm thick L shaped plates with 7 holes of which 1 hole was removed were fixed in maxilla with six $2.0{\times}7mm$ screws. Three $2.5{\times}16{\sim}18mm$ screws were used to fix superior ramus area and one mandibular angle area in mandible. It took about 27.4 minutes in maxilla, 25.3 minutes in mandible to perform the fixation which took longer time than the titanium system(9.5 minutes in maxilla, 8 minutes in mandible). Generally, there was no problem except 9 cases in which there were some complications. Conclusions : In most cases, the biodegradable fixation system can be used without problem in usual orthognathic surgery. But, this system is inferior to the titanium fixation one in some respects such as fixation time, size, and physical property. Some supplementations for such weak points as aforementioned should be needed for the universal use of biodegradable materials.

• 대한전자공학회논문지TC
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• 제45권9호
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• pp.49-54
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• 2008

본 논문에서는 class F 전력 증폭기의 출력 정합단에 새로운 광전자밴드갭(PBG) 구조를 적용하여 높은 효율을 얻을 수 있도록 하였다. 제안된 나선형 PBG 구조는 비평면 제조 공정을 요구하지 않는 유전체 판 위에 패턴을 뜬 2차원의 규칙적인 격자이다. 이 구조는 2차 고조파에서 높은 저지 특성을 갖는다. 또한 더욱 가파른 스커트 특성을 보인다. 이 새로운 PBG 구조는 효율향상을 위하여 class F 전력 증폭기에 적용되어 질 수 있다. 나선형 PBG 구조를 적용한 class F 전력 증폭기의 power-added efficiency(PAE)는 코드분할 다중접속(CDMA) 응용에서 73.62 %의 효율을 얻을 수 있었다. 이 결과는 제안한 PBG 구조를 적용하지 알은 기존의 Class F 전력 증폭기와 비교했을 때 6.2 % 향상된 결과를 보여준다.

• 농업과학연구
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• 제26권2호
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• pp.116-129
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• 1999

The objectives of the study mainly concentrated on identifying the political implication on genetically modified crops considering production potentials and problems. It is found that the comprehensive evaluation of the genetically modified crops could not be concluded and compromised in a word on account of the polarization and parallelism of the positive and negative benefits of genetically modified crops just like as the rail way. The genetically modified crops will be contributed to solving the food shortage problems in the world, when the issues such as food safety, ecological disturbance and loss and degradation of biodiversity can be guaranteed in transparency. And when the trade morality of the multi-national enterprises be accepted by the genetically modified crops consumers, the potentiality of genetically modified crops will be realized greatly. By the way, the first problems will be expected to be solved by scientific development. If the food safety of the genetically modified technology be verified in transparency, it will be greatly contributed to solve food problems of human beings in the world. But the second problem could not be expected to be easily solved from the view point of capital property. In conclusion, the genetically modified technology will be made a severe sense of incongruity and a seed of fire on it will be remained persistently. According to the results based on the analysing the genetically modified crops potentiality and problems, it was identified that the ex-ante preparation of counter-measures and actions on it should be necessary. Accordingly this study has recommended that how and what the R&D policy on genetically modified crops be established and suggested how to carried out the industrial and economic policy together with international negotiation, and organizational and institutional rearrangement and etc.