Earticle

코어의 유효공극률 측정에 있어서 그 정확성과 반복성을 높일 수 있도록 고체질량을 초기화하고 이건조상태를 지속시키는 방법을 제안하고 그 효과를 유효공극률과 전기비저항 측정을 통해 살펴보았다. 암석코어시험편이 겪은 환경 이력에 관계없이 내부를 완전하게 건조시켜서 고체질량을 초기화하고 필요에 따라서 이건조 상태를 지속시키는 방법으로 건조 공정 중에 질소가스(불활성가스)를 주입하는 기술을 고안하였다. 원주형시멘트 시험편에 대해 고안된 기술을 적용한 결과, 질소가스를 주입하면 공기에 포함된 수분이 시험편 내부로흡수되는 것을 효과적으로 차단 또는 지연시킬 수 있어서 시험편의 내부 수분을 최소화한 고체질량을 얻을수 있고 건조한 암석코어의 전기비저항을 장시간 모니터링할 수 있었다. 이를 토대로 유효공극률을 측정하는표준시험법의 수정을 제안하였다.

A method for initializing grain mass and maintaining dry condition of a core sample has been suggested. It is validated by effective porosity and resistivity measurements of cement core samples. Injection of noble gas such as nitrogen gas during the drying process of a core sample can ignore the environmental factors of the core beforehand and initialize the grain mass and sustain the core in dry condition for a while by keeping the pore space from infiltrating the humidity in the air. Injection of nitrogen gas into the dried cement cores effectively block or delay the humidity invasion into the pore space, so that one can get grain mass with minimum humidity in its pore space, and can perform an long term resistivity monitoring of the dry sample. Based on the suggested method and experiment results, it is suggested to modify the standard test method for effective porosity and density of rocks.

본 연구에서는 내열성 다이아몬드 절단공구를 이용하여 콘크리트를 절단할 때 절단면에 발생하는 열을 물 대신 초저온 순간냉풍으로 냉각하며, 절단 시 발생하는 분진은 집진장치로 처리하는 콘크리트 구조물 해체공법을 개발하였다. 콘크리트 절단시, 물대신 공기를 사용함에 따라 발생하는 초과마찰열에 견딜 수 있는 내열성 다이아몬드 와이어 톱을 개발하여 기존의 건식공법이 갖는 초 과열 문제를 해결하였으며 또한 본 기술은 기존의 물을 사용한 습식 절단공법의 문제점인 환경오염(토양, 수질, 대기, 해양)을 극소화 한 공법으로서 특히, 직접적으로 비산먼지, 수질오염 등에 피해를 받을 수 있는 다중 이용시설, 물의 사용이 금지 된 구조물, 수질보호지역 등에 적용할 수 있는 친환경적인 기술이다.

In this study, diamond wire saw based demolition method is developed, where high speed and low temperature dried air is used to cool the cutting surface instead of traditional cooling water. Heat resistant diamond wire saw and cooling air supplier, which are the core components of the present equipment, are designed and fabricated to overcome the overheating problems of the existing demolition method when cutting concrete structures. Practicability of the developed equipment is proved by measuring and analyzing the cooling performance of the cooling air system, in order to test on-site applicability. The developed technique is environment friendly dry demolition method to minimize the environmental problems such as soil/air pollution, water contamination and scattering dust, which can be suitable for multiplex facilities and structures in water pollution prevention area.

Ignition mechanism of dry bit which is applied to the exterior insulation finishing system in building is analysed and constructive methods to prevent the fire are suggested. For the experiment, surface finishing conditions, separation distances and kinds of ignition sources are selected as experiment variables, and danger of fire is confirmed through replication experiment. And through the re-ignition test, the fire ignition mechanism of the dry bit applied to the building is identified, and the fire prevention and casualty reduction measures are classified into institutional and technical aspects. Establishing practical preventive measures and technical alternatives that can be applied to the fire investigation are suggested.

The paper picking during printing is one of the most serious problems in printing press, which relate to the interaction between the ink and the paper. So far, It has been used many kinds of the devices and the machines as a pick test methods. However, the current pick test methods give little understanding of important mechanisms. In this report, the current pick test methods were briefly reviewed and a novel dry pick test method which we are proposing, was introduced.

원자력발전소내 습식저장중인 사용후핵연료의 건식저장을 위해서는 캐니스터 내부에 사용후핵연료를 옮겨 담은 이후, 건 식저장 캐니스터 내장품이나 사용후핵연료 다발의 부식방지 및 피복관의 열화방지를 위해 모든 수분은 제거해야 한다. 캐 니스터 내부의 수분을 제거하는데 사용할 수 있는 기체강제순환 건조시스템 개발을 위한 연구개발이 진행중이다. 본 연구 에서는 기체강제순환 건조시스템 설계, 제작을 위한 예비설계를 수행하였다. 예비설계에는 캐니스터 내부 잔존수분 제거를 위한 건조사례조사, 건조관련 규격이나 표준, 건조합격기준, 건조장치구성, 현장요구분석, 습식저장중인 사용후핵연료 특성 을 포함하였다. 예비설계를 통하여 기체강제순환 건조시스템의 설계 개념도와 P&ID를 도출하였고, 이를 활용하여 건조시 스템 제작을 위한 상세설계를 수행할 것이다.

For dry storage of the spent nuclear fuel (SNF) stored in the storage pool of a nuclear power plant, essentially all moisture must be removed to prevent corrosion of the assembly and canister internals and/or degradation of fuel cladding integrity after SNF canister loading operation. R&D work is now in progress on a forced gas drying system that can be used to remove residual water in canisters. In this work, preliminary design is performed to manufacture the forced gas drying system. This process includes a case study of dry methods for canister moisture removal, relative codes and standards, confirmation of adequate dryness, needs analysis at plant sites, and characteristics of SNF stored in pools. Through this preliminary design work, we obtained a conceptual flow diagram and preliminary P&ID of the forced gas drying system. The results of this study can be used to determine details of the design to manufacture the forced gas drying system.

This paper takes raw milk as research object, and using mid-infrared spectrum analysis method rapidly tests dry matter in raw milk through establishing quantitative analysis model. First of all, researchers collect 84 kinds of raw milk which is different areas and varieties in Heilongjiang province, and classify 84 samples into calibration sets and validation sets by standard chemical testing and spectral scanning on raw milk, and calibration sets contain 64 samples, and validation sets contain 20 samples. Then, respectively selecting SPA and GA characteristic wavelength after treating by smoothing denoising method which window size is 11 points, and establishing PLS model and model demonstration. Eventually, researchers draw the conclusion that SPA wavelength selection method which value of m_max is 10 and GA wavelength selection method which value of Evaluat is 10d can effectively improve validation set model precision, but precision of the latter is higher and characteristic wavelength point reduces from 352 to 10, The calibrating determination coefficient R2 of model is 0.8092155, root mean square error (RMSEC ) is 0.1206172. Validation set determination coefficient R2 is 0.8620867, the root mean square error (RMSEC) is 0.0950656, and relative standard deviation RSD<3%. These prove that the method for rapid testing of raw milk components is feasible.

식품의 안전성 평가에 사용되는 주요 지표 미생물들의 검출 시험법 중에서 전통적인 미생물 시험법과 신속 검출법인 건조 필름법에 의한 미생물 시험법 간의 유효성 관계를 국내 특정 축 수산식품에 존재하는 미생물을 대상으로 분석하였다. 축 수산식품 중 어묵, 게맛살, 아이스크림, 우유, 햄 시료에 대하여 두 가지 미생물 시험법을 각각 실시하였다. 일반 세균수 분석에는 plate count agar법과 aerobic count plate법을 비교하였고, 대장균군과 대장균의 분석에는 most probable number(MPN)법과 coliform count plate 및 E. coli/coliform count plate법을 각각 비교하였으며, 효모와 곰팡이의 분석에는 potato dextrose agar법과 yeast and mold count plate법을 비교하였다. 황색포도상구균의 분석에는 coagulase 시험법과 staph express count plate법을 비교하였다. 5가지 축 수산식품에 대한 두 방법들간 상관계수는 일반세균이 , 대장균군이 0.979-0.987, 대장균이 0.978-0.984, 효모와 곰팡이가 0.975-0.999, 황색포도상구균이 0.999로 두 방법간 상관성이 매우 높았으며, 평균 미생물 수에 있어서도 유의적인 차이가 없는 것으로 확인되었다. 이상의 결과로부터 건조필름법이 기존의 전통적인 시험 방법을 대체할 수 있는 미생물 분석법임이 확인되었다.

Contents of total aerobic bacteria, coliform, Escherichia coli, yeast, mold, and Staphylococcus aureus in meat, dairy, and fishery products were analyzed by dry rehydratable film method using 3M and compared against those obtained through conventional method. Two methods showed high correlations of 0.990-0.999, 0.975-0.999, 0.979-0.987, 0.978-0.984, and 0.999 for total aerobic bacteria, yeast and mold, coliform, E. coli, and S. aureus, respectively; therefore, dry rehydratable film method using 3M offers acceptable alternative to conventional method for enumeration of microorganisms in meat, dairy, and fishery products.

For the fast dry of the aqueous tape, the process which water was replaced by organic solvent was proposed. Socalled, it was the solvent washing dry. Three organic solvents (methanol, ethanol and acetone) were selected for the washing solvent. The weight loss of the washed tapes was measured to evaluate the dry rate of the tapes and dried tapes were examined the generation of the cracks with the variations of the organic solvent and the washing time. Methanol, ethanol and acetone were available organic solvents for this method. The tapes washed in methanol, ethanol and acetone were dried rapidly for twenty minutes. After thirty minutes, the weight losses were not found any more. The solvent of the lower surface tension can decreases the crack of dried tape. If solvent substitutes water completely, though it was fast dried, crack can be eliminated.

In order to find potential anticancer agents, we extracted pheophytin from silkworm feces according to various dry and storage methods such as sun dry, shade dry, fresh freezing dry and freezing dry after freezing storage (for 1∼3 years). The pheophytin extracts, mainly 10-hydroxypheophytin a, little b, of various storage silkworm feces were analyzed by reversed-phase high-performance liquid chromatography with photodiode array and fluorescence detection. The content of those pheophytih in old silkworm for 3 years (freezing storage and freezing dried in use, or freezing dried and cold storage) was better than others. The cytotoxicity of the pheophytin extracts and ethanol extracts of various storage silkworm feces were measured using Jurkat cells originated from human leukemia, using dye uptake assay (MTT) in order to find effective photodynamic therapeutic agents. The anticancer activity of those pheophytin extracts in various storage methods showed little difference among them. But ethanol extracts of fresh freezing dried silkworm in the current year was good cytotoxic activity than those of any other silkworm feces. With regards to these results, fresh ethanol extracts of silkworm feces were better than old ones. On the other hands, the pheophytin extracts of old silkworm feces contained the highest percentage of pheophytin content and showed good cytotoxicity against cancer cells by changing the pheophytin into pheophobide in the degradative process.

With a new PDP transparent dielectric layer formation technique, we were able to make dielectric layer with high transmittance by using dry film type dielectric material. We optimized dielectric pastes for dry film and they showed good process properties in lamination , drying and firing.

Most concrete is recently made of an aggregate which is properly absorbed, and carried in it in order to do capability at every fields. We have been close to demand new capability of high flowing and enduring for specific concretes. That is difficult to cope with claiming the efficiency on deterioration from lack of a high quality aggregate. Therefore, for solving the problems we apply to a packing method for using dried materials. That is to say it is a kind of making into an instant. In this study, There is a purpose to present fundamental data, comparing and analyzing a phenomenon about aggregate absorption following the rate of adding water, for using existing materials.

Purpose: The purpose of this study is to examine the effects of X-ray beam angulation on the fractal dimension of trabecular bone structure of human dry mandible using the tile counting method. Materials and Methods: We divided 5 human dry mandibles into an angle and a molar groups depending on the regions and deciding the region of interest (ROI). When contrasted with the ROI, the inferior cortex was appointed to be low and the lines perpendicular to the buccal cortex were appointed to be the standard angle. Direct digital intraoral radiographs were obtained from 9 different projection angles. We analyzed statistically the fractal dimension using the tile counting method. Results: There was a statistically significant difference in the fractal dimension of the regions and the mandibles, but there was no statistically significant difference in the fractal dimension according to the X-ray beam angulation. Conclusion : There is no statistically significant effect of the angle of the projection on the fractal dimension of trabecular bone structure of a human dry mandible according to the tile counting method.

Dry-cured pork neck samples were stored at $10^{\circ}C$ for 90 days under vacuum packaging (VP) or modified atmosphere packaging (MAP; 25% $CO_2$+75% $N_2$) conditions. The pH, moisture, water activity, total aerobic bacteria, and Enterobacteriaceae counts of dry-cured pork neck products with MAP were significantly lower than those with VP (p<0.05) after 90 days of storage. However, CIE $b^*$ and 2-thiobarbituric acid reacted substance (TBARS) values of the pork product with MAP were significantly higher (p<0.05) than those with VP. Total aerobic bacterial counts and Enterobacteriaceae counts of samples with MAP were lower than those with VP after 30 days of storage. Sensory results indicated that aroma, flavor and tenderness scores of the samples with both VP and MAP decreased during storage and the scores after >60 days of storage were lower than those at Day 1. In conclusion, despite presenting higher lipid oxidation, the samples stored in packages containing 25% $CO_2$ for 90 days at $10^{\circ}C$ have lower bacterial counts than vacuum-packed samples. Therefore, further studies should be performed on the packaging of dry-cured meat at adjusted concentrations of $CO_2$.

식품공전 시험법은 식품기초규격 적부 판정, 수거검사의 적부판정, 수입식품의 적부판정 등의 판단근거가 되기 때문에 식품산업에서 매우 중요하다. 본 연구는 도시락, 밀키트, 된장에 오염된 일반세균, 대장균군, 효모, 곰팡이, 대장균을 분리하기 방법으로 사용되는 평판배지법, Petrifilm법, Compact Dry법을 이용해 각각의 세균을 분리하였고, 회수율을 비교하였다. 식품 내 자연균총(일반세균, 효모/곰팡이, 대장균군)검출은 평판배지 PCA, PDA, DCLA와 Petrifilm AC, YM, CC의 성능을 Compact Dry TC, YMR, CF와 비교하였다. 인위접종한 대장균(E. coli)의 경우는 평판배지 EMB, Petrilfilm EC, Compact Dry EC의 검출능을 비교하였다. 본 실험결과, 일반세균, 대장균군, 대장균의 검출에서 Compact Dry법은 기존의 평판배지법 및 건조배지법과 비교하여 식품 내 각각의 세균수를 계수하는데 유의적 차이를 보이지 않았다(P>0.05). 또한, 평판배지법과 Compact Dry간의 상관관계 및 Petrifilm과 Compact Dry간의 상관관계 역시 1에 가까운 높은 값을 확인하였다. Compact Dry법은 미생물 분석을 위해 배지 준비 과정이 필요 없으며, 접종 후 자체 확산이 가능하여 사용하기 쉽고, 공간을 효율적으로 사용할 수 있으므로 기존의 배지를 사용하는 방법에 비해 많은 장점을 제공하였다. 따라서 식품 중 일반세균, 대장균군, 대장균의 검출을 위한 Compact Dry법(Compact Dry TC, CF, EC)은 기존의 식품공전 상 등재된 다른 건조필름법을 대체 가능한 것으로 판단된다.

The present study aimed to compare the accuracy of the compact dry and culture plate methods for natural flora (yeasts/molds, coliforms, and total bacterial count) and artificial inoculum (Escherichia coli) in dosirak (meat-based), meal kits (seafood-based), and Doenjang (traditional food). Compact dry TC, EC, CF, and YMR were compared with culture plate methods using a suitable medium for each bacterium. The total bacterial count, coliforms, yeasts/molds, and E. coli were assessed with 3M Petrifilm (aerobic bacterial, coliform, yeast/mold, and E. coli count plates) using culture plate methods. Analysis of the recovery rates of target microorganisms in the three food samples showed that the compact dry method for total bacteria, coliforms, and E. coli exhibited recovery capabilities equivalent to those of the culture plate and Petrifilm methods, with no significant differences (P>0.05). Overall, compact dry TC, CF, and EC showed a good correlation between the methods used in this study, indicating rapid and convenient microbial enumeration by saving time and requiring less space.

Waste vinyl tretreatment system has been developed by the joint project between KIMM and Woosung Co. General process for removal of impurities from waste vinyl is consisted of feeding, separating, cutting, washing, drying and recovering impurities. However, there are problems such as wastewater when washing of waste vinyl. In order to solve these problems we have developed new dry type cleaning system.

For the fast dry of the aqueous tape, the process which water was replaced by organic solvent was proposed. So-called, it was the solvent washing dry, Three organic solvents (methanol, ethanol, and acetone) were selected for the washing solvent. The weight loss of the washed tapes was measured to evaluate the dry rate of the tapes and dried tapes were examined the generation of the cracks with the variations of the organic solvent and the washing time. Methanol, ethanol, and acetone were all available organic solvents for this method. The tapes washed in methanol, ethanol, and acetone were dried rapidly for twenty minutes. After thirty minutes, the weight losses were not any more. The solvent of the lower surface tension can decreases the crack of dried tape. If solvent substitutes water completely, though it was fast dried, crack can be eliminated. The tape casting system was designed for the solvent washing dry and prepared. An homogeneous tape was established by continuous tape casting process.

Inkjet printing was successfully done using Cu nano powder ink after these Cu nano powders were dry-coated with 1-octanethiol for oxidation prevention. 1-octanethiol, which is Self-Assembled Multi-layers (SAMs), was coated approximately 10-nm thick on the surface of Cu nano powders. 1-Octanol, which has the same chain length as that for 1-octanethiol, was used as a solvent to make the ink for inkjet printing. As a result,the fabricated ink was dispersed for about 4 weeks, and after printing and heat treatment at 350oC for 4 hours, the resistivity for the printed pattern was measured to be 1.15×10^(?5)Ω · cm.

토양 내 유기물 덴 탄소 함량 분석을 위한 Tyurin법과 건식 연소법을 비교하기 위하여 우리나라 논과밭 토양에서 212점의 토양시료를 채취하여 분석을 실시하였다. 공시 토양의 탄소함량 평균값은 Tyurin법과 건식연소법에서 각각 17.47과 $19.91g\;kg^{-1}$을 나타내었다. 또한, 토양시료들의 표준편차의 평균값은Tyurin법과 건식연소법이 각각 0.80과 0.63으로 분석되었다. 이 결과로 미루어 볼 때, 두 분석방법 모두토양 탄소를 분석하는데 있어 좋은 분석방법으로 사용될 수 있음을 알 수 있었다. 한편, 토성에 따른 토양시료의 탄소함량에 미치는 영향을 분석한 결과 토성에 따른 탄소분석에서의 커다란 차이는 없는 것으로 판단되었다. 두 가지 분석방법으로 분석된 결과 값들을 비교하기 위하여 직선회귀식을 구한 결과 Y = 0.046X로 전체적으로 건식연소법 축으로 기울어지는 회귀식을 얻을 수 있었으며, 결정계수 $R^2$도 0.991로 매우 높은 유의성이 있었음을 알 수 있었다. Tyurin법과 건식연소법으로 분석된 토양 탄소함량을 직접 비교한 결과 건식연소법으로 분석한 결과 값의 약 69%가 높게 나왔으며 탄소함량이 증가할수록 건식연소법에서 분석하였을 때의 결과 값이 Tyurin법에 비해 높게 분석되고 있음을 알 수 있었다. Tyurin법과 건식연소법으로 분석된 탄소함량에 대한 표준편차를 비교한 결과 토양의 탄소함량이 낮을 경우의 표준편차의 분포가 표준편차의 전체 평균값 두 방법 모두 아래쪽에 분포한 반면 탄소함량이 증가할 경우 편차의 변이가 증가하였다 특히, Tyurin법의 경우 낮은 함량에서도 일부 편차가 큰 값을 나타내는 경우가 있었는데 이는 분석과정에서의 숙련도와 밀접한 관계가 있을 것으로 추정되었다. Tyurin법과 건식연소법의 분석과정을 비교해보면 1회에 통시에 분석할 수 있는 시료의 수는 Tyurin법에서는 20개 이하, 건식연소법에서는 60개 이하로 파악되었으며 소요되는 시약의 수도 Tyurin법은 5개인 반면 건식연소법은 6개에 불과하다. 그러나 한 개의 시료를 분석하는데 소요되는 평균시간은 Tyurin법의 경우 2.5분 이하로 건식연소법의 4분 이하보다는 적게 소요되는 것으로 파악되었다.

To compare soil carbon contents by Tyurin method and dry combustion method, we carried out analysis for 212 samples of agricultural land in Korea. The average values of soil carbon contents analyzed by Tyurin method and dry combustion method were $17.47{\pm}10.80$ and $19.91{\pm}10.63g\;kg^{-1}$, respectively. Both methods were evaluated as acceptable methods for soil carbon contents as the results showed. The results showed that soil texture had little effect on analysis method of carbon contents. Highly significant linear regression equation, Y = 0.846X ($R^2=0.991$), was obtained between carbon contents analyzed by Tyurin method (Y) and dry combustion method (X). As a result of comparison with data of carbon contents of the two methods, about 69% of results at dry combustion method have exceeded to results at Tyurin method. Especially, differences between results at two methods became higher as carbon contents were increasing. Tyurin method has been advantages such as shorter analysis time for one sample, more recognition for carbon analysis, and no need for expensive analyzer, while dry combustion method has simpler procedure, no heavy metal wastes, and more samples for analysis at one time.