• 한국버섯학회지
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• 제16권3호
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• pp.131-139
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• 2018

큰느타리버섯은 에르고스테롤 및 글루칸과 같은 기능성 물질의 함량이 높아 항산화 활성 및 프리바이오틱 효과를 일으키는 버섯이다. 큰느타리버섯은 향이 강하며 단단해 기호도가 높지만 장기간 소요되는 선박수출 등에서는 선도유지 기간 확보가 필요하다. 버섯의 품질에 영향을 미치는 외부요인은 온도, 상대습도, 공기조성 및 통풍 상태가 있으며 이로 인해 버섯의 호흡량, 수분 함량, 경도, 색도, pH 및 이취 등에 영향을 준다. 큰느타리버섯의 주요 장해는 갈변, 이취, 부패가 있으며, 이를 막기 위해 상품성이 높은 품종을 개발하거나 저장성을 높이는 처리 방법이 고안되고 있다. 버섯의 품질을 유지하기 위한 방법으로는 건조, 감마선 조사, 키토산 처리와 같은 수확 후 처리 방법과 CA 저장과 MA 포장을 통한 저장 방법이 있다. 버섯의 건조는 자연건조, 열풍건조, 동결건조, 진공건조, 전자파진공건조 방법이 있으며 동결건조 방법을 사용한 버섯의 성분저하가 비교적 낮았다. 1 kGy 감마선 조사가 고선량에 비해 저장기간 연장에 효과적이었으며 오일, protocatechuic acid, 왁스 등의 친수성 colloid를 키토산에 첨가하여 코팅처리 하였을 때 경도유지, 호흡 및 갈변이 억제되었다. 큰느타리버섯의 CA 저장조건은 $10^{\circ}C$ 이하의 온도에서 5kPa $O_2$ + 10~15kPa $CO_2$의 공기 조성이 제시되었으며 MA 포장으로는 미세천공을 갖는 PP필름을 이용한 능동적 기체조성 방법이 저장 중 품질유지에 효과적이었다.

• 한국지반공학회논문집
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• 제40권1호
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• pp.47-54
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• 2024

기존의 사면안정해석은 포화토 이론에 기반하여 비탈면 안정성에 대한 평가가 진행되었다. 그러나 자연 지반은 기후에 따라 함수 특성이 변화하기 때문에 포화토 이론은 한계가 있어 불포화토의 특성을 고려한 안정해석 연구가 필요하다. 또한, 실제 불포화토 지반은 호우로 인해 모관흡수력이 감소하여 사면 안정성의 저감을 유발하기 때문에 이에 대한 공학적 특성을 평가하는 것이 중요한 실정이다. 본 연구에서는 국내 산지에 내포된 화강풍화토를 활용하여 세립분 함량을 0%, 10%, 20%, 30%로 구분한 4가지 시료를 통해 흙-함수 특성 시험을 수행하였으며, 특히 건조과정뿐만 아니라 실제 사면에서 호우로 인한 안정성 평가를 고려하기 위해 함수비를 증가시키는 습윤과정을 진행하였다. 또한, 다양한 이론식을 적용하여 실험에 가장 일치하는 이론식인 van Genuchten(1980) 모델을 활용하였으며, 건조과정과 습윤과정에 대한 화강풍화토의 세립분에 따른 파라미터를 분석하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.416-416
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• 2016

Organic-inorganic metal halide perovskite solar cells have received attention because it has a number of advantages with excellent light harvesting, high carrier mobility, and facile solution processability and also recorded recently power conversion efficiency (PCEs) of over 20%. The major issue on perovskite solar cells have been reached the limit of small area laboratory scale devices produced using fabrication techniques such as spin coating and physical vapor deposition which are incompatible with low-cost and large area fabrication of perovskite solar cells using printing and coating techniques. To solution these problems, we have investigated the feasibility of achieving fully printable perovskite solar cells by the blade-coating technique. The blade-coating fabrication has been widely used to fabricate organic solar cells (OSCs) and is proven to be a simple, environment-friendly, and low-cost method for the solution-processed photovoltaic. Moreover, the film morphology control in the blade-coating method is much easier than the spray coating and roll-to-roll printing; high-quality photoactive layers with controllable thickness can be performed by using a precisely polished blade with low surface roughness and coating gap control between blade and coating substrate[1]. In order to fabricate perovskite devices with good efficiency, one of the main factors in printed electronic processing is the fabrication of thin films with controlled morphology, high surface coverage and minimum pinholes for high performance, printed thin film perovskite solar cells. Charge dissociation efficiency, charge transport and diffusion length of charge species are dependent on the crystallinity of the film [2]. We fabricated the printed perovskite solar cells with large area and flexible by the bar-coating. The morphology of printed film could be closely related with the condition of the bar-coating technique such as coating speed, concentration and amount of solution, drying condition, and suitable film thickness was also studied by using the optical analysis with SEM. Electrical performance of printed devices is gives hysteresis and efficiency distribution.

• 생명과학회지
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• 제8권1호
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• pp.60-66
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• 1998

G- 및 C-banding법에 의한 ICR 생쥐의 유사분열과 감수분열 시기의 염색체 특징에 관하여 조사하였다. 이를 위한 염색체 표본 작성은 Imai et al.의 공기건조법을 다소 변형한 방법에 의하였다. 정소를 이용한 염색체 분석은 유사분열뿐만 아니라 감수분열단계들을 모두 관찰할 수 있었으며, C-banding에 의하여 X 염색체를 포함한 모든 염색체의 돈원체 부위가 강하게 염색되었다. 정상의 제 1 감수분열 전기와 중기 사이의 세포들에서 2가 염색체로 된 19쌍의 상염색체과 1개의 말단결합으로 된X-Y 염색체를 관찰할 수 있었다. 대조군의 제 1 정모세포에서 조기분리된 성염색체를 가지는 세포의 빈도는 약 7.45%였으나,alkylating agents 처리군에서는 대조군에서보다 약 3-4배 이상 높에 나타났다. 그리고 감수분열 단계의 염색체 표본에 C-banding을 적용함으로서 X-Y 염색체 조기분리의 관찰이 매우 용이하였다.

• Bulletin of the Korean Chemical Society
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• 제35권11호
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• pp.3275-3279
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• 2014

A mass balance method for purity assessment of thermolabile organic reference materials was established by combining several techniques, including liquid chromatography with UV/VIS detector (LC-UV), Karl-Fischer (K-F) Coulometry, and thermal gravimetric analysis (TGA). This method was applied to three fluoroquinolones like enrofloxacin, norfloxacin and ciprofloxacin. LC-UV was used to analyze structurally related organic impurities based on UV/VIS absorbance spectra obtained in combination with LC separation. For all three organic reference materials, the UV/VIS spectra of the separated impurities were similar to that of the major component of the corresponding materials. This indicates that the impurities are structurally related to the respective reference material sharing common chromophores. Impurities could be quantified by comparing their absorbances at the wavelength of maximum absorbance (${\lambda}_{max}$). The water contents of the reference materials were measured by K-F Coulometry by an oven-drying method. The total inorganic impurities contents were assayed from ash residues in TGA analysis with using air as a reagent gas. The final purities estimated from results of those analytical techniques were assigned as ($99.91{\pm}0.06$), ($97.09{\pm}0.17$) and ($91.85{\pm}0.17$)% (kg/kg) for enrofloxacin, norfloxacin and ciprofloxacin, respectively. The assigned final purities would be applied to the reference materials which will be used as calibrators for the certification of those compounds in matrix CRMs as starting points for the traceability of their certified values to SI units.

• 한국동물학회지
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• 제8권1호
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• pp.11-14
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• 1965

The object to this study is to identify the genus and species of the microfilariae which were recently found in the area of Youngju-Gun. THe identification of the microfilariae was made on the morphologicla aspects. 1. Blood samples were collected through vena punction from known microfilariae carriers living in the newly confirmed filaria endemic area of Youngju0Gun in Jyongsang Pukdo Province. Youngju-Gun is located in the mountainous central part of Korean Peninsula. 2. The following fixation and staining techniques were applied. (1) Fixation by drying in the air, followed by staining with Azeo or Giemsa. (2) Knott's fixation method (2% formalin), followed by staining with Azur II. 3. A comparative study of the body length of the microfilariae after different fixation and staining techniques were applied. (1) Knott's fixation method followed by staining with Azur II : average body length found was 28.4$\mu$. (2) Dry fixation followed by staining with Giemsa : average body length found was 209.4$\mu$. (3) Dry fixation followed by staining with Azeo : average body length found was 205.4$\mu$. 4. The locations of the different body cells were measured in 60 individuals of microfilariae in the wet preparation fixed by Knott's method and stained with Azur II. The distance of the different body cells to cephalic apex of microfilariae was measured and calculated as a percentage of the total body length. The average results are as follows : BNC , 3.04% ; N, 22.74%, EP, 31.4% ; EC, 37.77%, G1 cell , 67.94%; G2 cell, 73.54% : G3 cell , 75.55% ; G4 cell, 77.65% ; AP, 82.02%%. 5. As a result of the above findings the microfilariae found in the above mentioned area could be identified as Brugia malai(BRUG, 1927) BUCKLEY, 1960.

• The Journal of Advanced Prosthodontics
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• 제13권4호
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• pp.237-245
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• 2021

PURPOSE. This study aimed to compare the microshear bond strength (µSBS) of dual-cure resin cement in CAD-CAM zirconia after different cleaning techniques. MATERIALS AND METHODS. Fifty discs of zirconia-based ceramic from Ivoclar Vivadent were embedded in acrylic resin. The discs were divided into five groups according to the cleaning methods used: Group 1: drying with spraying + sandblasting with Al₂O₃; Group 2: washed with water and dried with spraying + sandblasting with Al₂O₃;Group 3: washed with distilled water and dried with spraying + sandblasting with Al₂O₃ + zirconium oxide (Ivoclean); Group 4: washed with distilled water and dried with spraying + sandblasting with Al₂O₃ + potassium hydroxide (Zirclean); and Group 5: washed with distilled water and dried with spraying + sandblasting with Al₂O₃ + 1% NaClO. All of the groups were contaminated with artificial saliva for 1 minute and then cleaned. Statistical analyses were performed using ANOVA and Tukey's tests. RESULTS. There were statistically significant differences among all groups for µSBS (P < .05). The group treated with zirconium oxide (Group 3) showed the highest µSBS (18.75 ± 0.23 MPa). CONCLUSION. When applied to zirconia, the cleaning methods affected the bonding with resin cement differently.

• 디지털융복합연구
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• 제20권5호
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• pp.819-825
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• 2022

전문 직업인으로서 자질과 실력을 검증하기 위한 미용사 국가기술 자격증의 중요성이 증가하는 가운데 헤어 실기과제에 대하여 헤어디자이너가 지각하는 직무 태도 연구를 통해 성취동기와 직무 태도 향상이 필요한 시점이다. 이에 헤어살롱에서 근무하는 헤어디자이너의 직무 태도에 미치는 영향을 연구한 결과 미용사 헤어 국가기술 자격증 실기과제 중 블로우 드라이는 헤어디자이너의 직무 효능감을 유발하는 것으로 나타났고, 두피 스켈링과 샴푸는 헤어디자이너의 직무만족도를 유발하는 것으로 나타났다. 연구 결과를 바탕으로 가발에만 국한되는 비현실적 실기기법이 아닌 미용산업체에서 고객에게 다양한 기법으로 유용하게 적용할 수 있는 실용성을 가미한 자격증 실기과제에 대한 다양한 제시가 가능해지며, 체계적인 교육과 헤어디자이너의 직무 태도 향상을 유도하고자 한다. 더불어 본 연구는 헤어디자이너의 성취동기 향상을 위한 다양한 실기과제 개발의 기초자료를 제공하리라 사료한다.

• International Journal of Concrete Structures and Materials
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• 제6권3호
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• pp.145-153
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• 2012

The aim of this study is to explore the possibility of re-cycling a waste material that is now produced in large quantities, while achieving an improvement of the mechanical properties and durability of the mortar. This study examines the mechanical properties and the durability parameters of mortars incorporating plastics bag wastes (PBW) as fine aggregate by substitution of a variable percentage of sand (10, 20, 30 and 40 %). The influence of the PBW on the, compressive and flexural strength, drying shrinkage, fire resistance, sulfuric acid attack and chloride diffusion coefficient of the different mortars, has been investigated and analyzed in comparison to the control mortar. The results showed that the use of PBW enabled to reduce by 18-23 % the compressive strength of mortars containing 10 and 20 % of waste respectively, which remains always close to the reference mortar (made without waste). The replacement of sand by PBW in mortar slows down the penetration of chloride ions, improves the behavior of mortars in acidic medium and improves the sensitivity to cracking. The results of this investigation consolidate the idea of the use of PBW in the field of construction.

• 복식
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• 제58권8호
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• pp.63-73
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• 2008

From the ancient Korea to the late Joseon Korean fur and leather had been preferred in and out of Korea for their good quality and excellent manufacturing skill. Since Unified Silla (A.D.676${\sim}$A.D.936) Korean fur and leather were manufactured divisionally by workmen specialized in materials and products, and such manufacturing process was succeeded to Goryeo and Joseon. Manufacturing of fur and leather was consisted of as follows: hunting and butchering - peeling - beating with a paddle and removing fat - oil manufacturing - drying - tanning, then cutting and sewing, and there was a special caring method. In order to make good fur and leather, each process of manufacturing needed particular techniques and all available methods were tried to have tender fur and leather by using smoking, excrement, lime, vegetable tannin and even cerebral liquid. And also required mouth-chewing and hand-pounding with a lot of time and of labor Keeping furs resilience and flexibility, sowing several skins together, even when the after-all-process skin was converted into clothes, was much more difficult than sewing fabric. Thus, the manufacturing cost was as much expensive as skin materials, and the volume of manufacturing of fur and leather was also limited. Therefore, fur and leather must have been popular for scarcity value in the manufacturing process, and this scarcity must have caused an extreme luxury of fur.