This study was performed to evaluate changes of microbiological and hygienic quality characteristics of dry-cured ham during manufacturing process. The water activity(Aw) of dry-cured ham decreased significantly during the period(P<0.05). The salt contents increased from at 0 day to 60 days and decreased slightly at 60 days of post-curing(P<0.05). The contents increased after 120 days again. As the curing, drying and aging progressed, the VBN and TBA of dry-cured ham increased(P<0.05). The dry-cured ham samples showed significantly higher VBN at 120 and 180 days and higher TBA at 180 days. Regarding microbiological analysis, the total aerobic counts and lactic acid bacteria counts increased significantly during the stage(P<0.05). The total aerobic counts closely paralleled the lactic acid bacteria counts. In general, this research can be used as fundamental information for the mass production of a hygienic dry-cured ham.

In manufacturing company, safety is a important issue because it can cause many cost and problems of company. So reduce safety accident can increase manufacturing company's productivity. Safety accident has close relationship with employee's behavior, which is 'safety behavior'. In this study, researcher try to find out role of leader-member exchange and employee's job commitment effect on safety behavior in manufacturing company. A total of 279 responses were collected from manufacturing company’s employees. The result of this empirical study show us that leader-member exchange has positive effect on employee's job commitment and safety behaviot. And job commitment has positive effect on safety behavior. Base on this empirical result, researcher provide critics and manageric implication for manufacturing companies.

전기방사는 높은 비표면적을 가지는 마이크로∼나노 단위 직경의 나노섬유를 생산하는 간단하고 효율적인 공정이 다. 따라서 식물 추출물과 폴리머를 혼합한 방사용액으로 손쉽게 의료용 나노섬유의 제조가 가능하다. 향나무는 라 디칼 생성, 화상, 세포손상과 같은 자외선과 SLS에 의한 피부손상을 방지하는데 효과적이라고 알려져 있다. 또한 방미효과와 함께 집먼지 진드기 방지 효과가 보고된 바 있다. 전기방사로 향나무 추출물을 함유하여 제조한 PVA 나노섬유를 연구하였다. 향나무 추출물의 서로 다른 농도(0.25, 0.5, 1.5 wt. %)를 함유하는 PVA/향나무 추출물 나노 복합섬유를 제조하였으며 방사용액의 농도, 인가전압, TCD 등의 전기방사 조건을 최적화 하였다. 연구결과 균일한 PVA/향나무 추출물 나노 복합섬유을 얻을 수 있는 최적 조건으로 PVA 농도는 12wt%, 인가전압은 10 Kv, TCD는 10∼20 cm로 나타나났다. 제조된 전기방사 나노 복합섬유의 형태 및 미세구조를 SEM을 통해 관찰하였다. 향나무 추출물의 첨가에 의해 나노섬유의 직경이 증가하는 것으로 나타났다. 결과적으로 310∼360 nm의 직경범위를 가지 는 PVA/향나무 추출물 복합 나노섬유가 전기방사를 통해 성공적으로 얻어졌다.

Product liability (PL), which began enforcement in 2002, refers to the legal responsibility of the manufacturers or sellers (wholesales or retailers) for the property damage or bodily harm caused by their product. With a strong enforcement of the Product Liability (PL) Act, companies are required to structure and operate a response system to defend or prevent product accidents efficiently, but small and medium enterprises (SMEs) are unable to respond more aggressively due to limitation of management resources. In this manner, it is important to develop response strategies for SMEs to efficiently cope with the PL Act. In this paper, the PEST (Political, Economic, Social, and Technological) analysis is performed to reveal the impact of the PL Act on SMEs in macro-economic point of view. To formulate SME’s PL response strategy, SWOT analysis is performed to categorize each factors from PEST analysis and AHP is applied to identify the intensities of SWOT factors. The prioritized SWOT factor, results of PEST-SWOT-AHP analysis, are used to formulate SME’s PL response strategies. The study results are briefly summarized as follows. To reduce product defects, it is necessary for SMEs to formulate PL response strategies for each phase of the product life cycle by continuously collecting and analyzing PL cases in the same industry or for similar products. In addition, SMEs should invest more technological effort to ensure product safety. Further, SMEs should spread PL awareness to all staff members by training internal PL experts. Moreover, a SME should enroll in PL insurance and spread this information to its customers so that they become aware that the company is proactively conforming to the PL law.

This study organizes not only the middle-long term developing plan of safety health education to put emphasis on a manufacturing industry, but also the developing plan of activating the domestic safety health education. On the basis of this study, current safety health education can be developed. To achieve a goal of implementing domestic safety health education, this study is carried out more deeply as follows.

목 적: 본 연구는 광 변색 콘택트렌즈 제조에 필요한 spiropyran을 합성하여 캐스트몰드공법과 샌드위치 공법으로 광 변색 콘택트렌즈를 제조하고, 각각의 특성을 비교하여 광 변색 콘택트렌즈의 가능성을 확인하 고자 한다. 방 법: 캐스트몰드공법은 spiropyran과 HEMA, EGDMA, NVP, MMA와 함께 공중합 하여 제조하였고, 샌드위치공법으로는 HEMA, EGDMA, NVP, MMA를 1차 공중합 하여 제조한 콘택트렌즈 표면에 spiropyran을 바인더와 혼합하여 흐름 코팅 후 그 위에 HEMA, EGDMA, NVP, MMA를 2차 공중합 하여 제조하였다. 그리고 각각 제조된 렌즈의 물리적 특성을 평가하기 위해 함수율, 접촉각을 측정하였다. 자외 선에 의해 광 변색 기능을 확인하기 위해 자외선을 1분간 조사 후 색상 변화 및 흡광도를 측정하였으며, 이 후 암실에서 10분 후에 다시 측정하였다. 결 과: 캐스트몰드공법으로 제조한 콘택트렌즈의 함수율과 접촉각은 35.21%와 70.80°이었으며, 자외선 에 의한 광 변색 기능은 전혀 없는 것으로 나타났다. 반면 샌드위치공법으로 제조한 콘택트렌즈의 함수율과 접촉각은 40.35%와 47.85°이었으며, 자외선에 의해 보라색으로 변색되었고 암실에서 투명해지는 광 변색 기능을 확인할 수 있었다. 결 론: 캐스트몰드공법으로 제조한 콘택트렌즈의 경우 자외선에 의해 변화가 전혀 없는 것으로 나타나 광 변색 콘택트렌즈의 기능을 하지 못하는 것으로 나타났다. 그러나 샌드위치공법에 의해 제조된 광 변색 콘택 트렌즈는 함수율과 접촉각 등에 큰 영향을 주지 않으면서 빠른 광 변색 특성을 나타내어 광 변색 콘택트렌즈 의 제조에 적합할 것으로 사료된다.

Cu-30 vol% SiC composites with relatively densified microstructure and a sound interface between the Cu and SiC phases were obtained by pressureless sintering of PCS-coated SiC and Cu powders. The coated SiC powders were prepared by thermal curing and pyrolysis of PCS. Thermal curing at 200 oC was performed to fabricate infusible materials prior to pyrolysis. The cured powders were heated treated up to 1600 oC for the pyrolysis process and for the formation of SiC crystals on the surface of the SiC powders. XRD analysis revealed that the main peaks corresponded to the α-SiC phase; peaks for β-SiC were newly appeared. The formation of β-SiC is explained by the transformation of thermally-cured PCS on the surface of the initial α-SiC powders. Using powder mixtures of coated SiC powder, hydrogen-reduced Cu-nitrate, and elemental Cu powders, Cu-SiC composites were fabricated by pressureless sintering at 1000 oC. Microstructural observation for the sintered composites showed that the powder mixture of PCS-coated SiC and Cu exhibited a relatively dense and homogeneous microstructure. Conversely, large pores and separated interfaces between Cu and SiC were observed in the sintered composite using uncoated SiC powders. These results suggest that Cu-SiC composites with sound microstructure can be prepared using a PCS coated SiC powder mixture.

Porous SiC beads were prepared by freeze-drying a polycarbosilane (PCS) emulsion. The water-in-oil (w/o) emulsion, which was composed of water, PCS dissolved p-xylene, and sodium xylenesulfonate (SXS) as an emulsifier, was frozen by dropping it onto a liquid N2 bath; this process resulted in 1~2 mm sized beads. Beads were cured at 200 oC for 1 h in air and heat-treated at 800 oC and 1400 oC for 1 h in an Ar gas flow. Two types of pores, lamella-shaped and spherical pores, were observed. Lamellar-shaped pores were found to develop during the freezing of the xylene solvent. Water droplets in the w/o emulsion were changed into spherical pores under freeze-drying. At 1400 oC of heat-treatment, porous SiC was synthesized with a low level of impurities.

본 연구는 기업⋅혁신⋅산업 특성이 기업의 전유전략에 미치는 영향을 특허와 영업비밀의 상대적 선호를 중심을 ‘한국기업혁신조사’ 2005, 2010, 2014년 자료를 통해 분석 하였다. 분석결과 벤처기업, 고기술산업에 속한 기업, 정부의 연구개발 자금지원을 받은 기업, 제 품혁신 수행기업과 연구개발 지출이 높은 기업에서 특허를 영업비밀보다 상대적으로 선호하 는 것으로 나타났다. 그러나 기업규모와 연구개발 협력여부는 통계적으로 유의한 영향을 미 치지 않았다. 이는 산업별 특성을 고려한 전유제도 정책이 보다 효과적일 수 있다는 것을 보 여준다. 높은 시장집중도를 가진 산업에 속한 기업들은 영업비밀을 선호하는 것으로 나타났으며, 이러한 특성은 소기업과 벤처기업에서 명확히 나타났다. 이는 선도기업의 전략적 특허출원의 증가가 소기업과 벤처기업의 특허활동을 제약할 수 있다는 것을 의미한다. 과도한 전략적 특허의 증가는 궁극적으로 소규모 기업들의 기술활동을 저해할 가능성이 있기 때문에 불필 요한 전략적 특허의 남용을 방지할 수 있는 정책적 노력이 필요할 것이다.

The purpose of this study was to formulate the optimal ratio of tofu ice cream made with crushed tofu and soybean milk. Also, to compare characteristics of tofu ice cream and soybean ice cream. Mix viscosity, overrun and melting down are measured as characteristics of ice cream. The optimal mixing ratio of tofu ice cream was determined by response surface methodology based on overall quality. As a result of optimization, tofu ice cream was made with 65.90% tofu cream (9% solid contents), 4.35% whipping cream, 14.35% canola oil, 15.00% sugar, 0.2% emulsifier and 0.2% guar gum. Soybean ice cream made with three different treated (blanched, steamed, roasted) soybean and each preprocess are treated for 0-20 min. Mix viscosity was enhanced preprocessing time increasing. Also, overrun and melting down was decline preprocessing time increased. As a result of comparison of ice cream overall quality, 15 min roasted soybean ice cream was shown the best quality.

Proteolytic enzymes were screened to obtain anchovy protein hydrolysates (APH) with low-bitterness under pressurization. First, the residual proteolytic activity (%) and SDS-PAGE of commercially available food-grade protease (Alcalase® 2.4 L, FlavourzymeTM 500 MG, Neutrase®, ProtamexTM) and mixed enzyme (ME, Alcalase® : FlavourzymeTM = 1 : 5) after treatments of ambient pressure and 100 MPa at 50oC were investigated. The proteolytic activity of enzymes was still largely retained after pressure treatment. The SDS-PAGE on tested enzymes showed that the electrophoretic mobility maps (EMMs) after pressure treatment were similar to those at ambient pressure. With these results, it seemed that tested enzymes were stable at 100 MPa and 50oC. Raw anchovy hydrolyzed with various protease at 50oC under ambient pressure and 100 MPa for 1, 2, 6, 12, and 24 h. The degree of hydrolysis (DH, %) of prepared APHs at 100 MPa was increased, which suggests that the medium pressure treatment accelerates protein hydrolysis. The APH by ME exhibited the best suitable characteristics, which had a relatively higher DH (36.2±1.8- 57.5±2.8), a high content of oligopeptides with a molecular mass lower than 1,100 Da, mildly bitter taste as the bitterness value was lower than that of 0.2 g/L tea alkaloid, and the lowest contents of tryptophan. Thus, ME was selected to obtain APH with low-bitterness under pressurization.

Glass-ceramics were developed many years ago and have been applied in many fields such as electronics, chemistry, optics, etc. Much is already known about glass-ceramic technology, but many challenges in glass-ceramic research are still unresolved. Recently, large amounts of slag have steadily increased in the steel industry as by-products. To promote recycling of industrial waste, including steel industry slags, many studies have been performed on the fabrication of basalt-based highstrength glass-ceramics. In this study, we have fabricated such ceramics using various slags to replace high performance castbasalt, which is currently imported. Glass-ceramic material was prepared in similar chemical compositions with commercial cast-basalt through a pyro process using slags and power plant by-product (Fe-Ni slag, converter slag, dephosphorization slag, Fly ash). The properties of the glass-ceramic material were characterized using DTA, XRD, and FE-SEM; measurements of compressive strength, Vicker’s hardness, and abrasion were carefully performed. It is found that the prepared glass-ceramic material showed better performance than that of commercial cast-basalt.

Fluorine-doped tin oxide (FTO) nanoparticles have been successfully synthesized using ultrasonic spray pyrolysis. The morphologies, crystal structures, chemical bonding states, and electrochemical properties of the nanoparticles are investigated. The FTO nanoparticles show uniform morphology and size distribution in the range of 6-10 nm. The FTO nanoparticles exhibit excellent electrochemical performance with high discharge specific capacity and good cycling stability (620mA h g−1 capacity retention up to 50 cycles), as well as excellent high-rate performance (250 mA h g−1 at 700mAg−1) compared to that of commercial SnO2. The improved electrochemical performance can be explained by two main effects. First, the excellent cycling stability with high discharge capacity is attributed to the nano-sized FTO particles, which are related to the increased electrochemical active area between the electrode and electrolyte. Second, the superb high-rate performance and the excellent cycling stability are ascribed to the increased electrical conductivity, which results from the introduction of fluorine doping in SnO2. This noble electrode structure can provide powerful potential anode materials for high-performance lithiumion batteries.

Octahedral Co3O4/carbon nanofiber (CNF) composites are fabricated using electrospinning and hydrothermal methods. Their morphological characteristics, chemical bonding states, and electrochemical properties are used to demonstrate the improved photovoltaic properties of the samples. Octahedral Co3O4 grown on CNFs is based on metallic Co nanoparticles acting as seeds in the CNFs, which seeds are directly related to the high performance of DSSCs. The octahedral Co3O4/CNFs composites exhibit high photocurrent density (12.73 mA/m2), superb fill factor (62.1 %), and excellent power conversion efficiency (5.61 %) compared to those characteristics of commercial Co3O4, conventional CNFs, and metallic Co-seed/CNFs. These results can be described as stemmnig from the synergistic effect of the porous and graphitized matrix formed by catalytic graphitization using the metal cobalt catalyst on CNFs, which leads to an increase in the catalytic activity for the reduction of triiodide ions. Therefore, octahedral Co3O4/CNFs composites can be used as a counter electrode for Pt-free dye-sensitized solar cells.

The purpose of this study is to improve a process of the automatic manufacturing system for producing a phosphor bronze wire developed the previous study. For this purpose, the authors have improved the manufacturing process, such as wire tension control, discoloration, winding and the control appears as a problem when the automatic manufacturing system applied to the field. Also, performance tests for the developed system such as the straightness, tensile strength, hardness, diameter deviation, discoloration have been performed. As a result, we could product the 0.35mm of phosphor bronze wire with continuous processes. The performance of the prototype system satisfies all the objects of this study.

The purpose of this study is to develop the automatic manufacturing system for producing a phosphor bronze wire. Automatic continuous manufacturing system is necessary to raise the productivity and strengthen the competitiveness in the phosphor bronze wire manufacturing. For this purpose, the authors carrying out the design and production of devices such as raw material supply, drawing, heat treatment, winding and main control system, etc. As a result, we could product the 0.35mm of phosphor bronze wire with continuous processes.

습식 동 제련공정은 황화광석을 원료로 하며, 제련 공정 중 약 2~15%의 폐황산이 발생하게 된다. 이 황산용액에는 유가금속(Cu, Zn) 및 희소금속(In, Se, Re 등)은 보통 수 ppm에서 수 % 단위로 용해되어 있으며, 첨단소재로서의 희 소금속 및 유가금속의 용도 및 수요가 다양해짐에 따라 이를 회수하여 활용하는 방향으로 연구가 진행되고 있다. 막분리를 이용하여 희소금속을 분리할 시 효율적이며 친환경적인 장점이 있다. 본 연구에서는 폴리에틸렌이민, 피페라진, 트리메조일클로라이드 용액을 사용하여 다공성 지지막 위에 폴리아미드 계면중 합을 하였으며, 제조된 분리막의 투과 특성 및 15%의 황산용액에 대하여 내산성 특성을 살펴보았다.

본 연구에서는 2차 암모늄기를 가지는 PEEK계 고분자 소재를 합성하였으며 이를 이용하여 분리막을 제조한 후 연료전지 적용을 위한 특성평가를 진행하였다. 이온교환능기의 함량에 따른 분리막의 물성변화에 대해 관찰하였으며, 기존의 폴리에테르에테르케톤 고분자에 비해서 도입된 암모늄기의 함량이 증가함에 따라 이온교환능 및 이온전도도가 향상이 되었으며, 비스페놀 에이계 단량체 도입을 통해서 용해의 용이성을 증가하여 가공성이 향상된 것을 확인 할 수 있었다. 특히 일부 샘플의 경우 장기 안정성 테스트 진행 후에도 분리막의 형상을 유지 함으로써 우수한 내 알칼리성을 나타내는 것을 확인할 수 있었다.

분리막을 이용한 산업은 석유에너지 자원의 고갈과 동시에 친환경 에너지자원의 필요성이 대두되어 최근들어 많은 연구가 이루어지고 있다. 이온기 그룹을 포함하는 고분자 분리막의 경우 해수담수, 전지시스템 등 친환경 에너지 자원의 개발과 더불어 많은 연구가 이루어지고 있다. 본 연구에서는 이온교환 관능기를 포함하는 탄화수소계열 고분자를 합성하여 준비한 후 소수성의 고분자와 블렌 딩을 진행하였으며 이에 따른 이온교환능 및 이온전도도를 분석하여 연료전지용 고분자 전해질 막에 대한 평가가 이루어졌으며, 폴리에테르에테르케톤계 고분자의 내열성 및 우수한 물리적 강도를 가짐과 동시에 우수한 이온전도도를 나타내는 것을 확인 할 수 있었다.

폴리벤즈이미다졸(PBI)은 우수한 내열성, 내화학성으로 잘 알려진 슈퍼 엔지니어링 플라스틱이다. 이러한 최상위 급의 물성을 지녔음에도 불구하고 PBI는 가 공성이 매우 떨어지기 때문에 다양한 분야의 적용에 한계를 지닌다. 기존 압축 성형을 이용한 PBI 성형물은 무게가 가벼우면서 우수한 강도 및 내열성을 나타내어 가혹한 환경을 가지는 산업분야에서 주로 사용되어 왔으나, 기체에 의한 open, closed pore의 조절, 싱크마크, 스프링백 등과 같은 압축성형 공정 자체 의 문제점 때문에 양질의 결과물을 얻기 힘들다. 본 연구에서는 이러한 문제를 해결하기 위하여 개선 된 고온 압축성형방법을 이용하여 PBI 압축성형물을 제 조하였고 고성능의 압출성형물 이상의 물성을 지니기 위하여 개질 된 카본나노 튜브와 그래핀 옥사이드를 도입하여서 기계적 강도를 높이고자 하였다. 각각의 보강제들은 초음파균질기를 통하여 고분자 용액에 골고루 분산되었고, 인장강도와 굽힘강도를 측정하기 위해 각각 ASTM규격에 맞는 압축성형 시편을 제작하였으며 UTM장비를 통해 강도 및 모듈러스를 측정하고 비교하였다.