PTEF membranes are used for roofing materials of membrane structures. PTEF is the abbreviation of Poly-tetra Fluotide-ethylene. These materials are consisted of fiberglass weave and polyetrfluoroethylene coating. Also, PTEF membranes have some problems of structural capacity by wind or snow load, etc. In this study, sensor housings using lead switches are bonding in PTFE membranes, Monitoring to changes tension and tear damages are studied using radio frequency. If tension is received on edged membranes, bonded lead switches of sensor housings will be destroyed by changes tension, and these become to send signals of damages at the connected radio frequency system with increased tension. Study of these functional membrane materials will be contributed to prevent water leakage and long-term maintenance of membrane structures.

Activated carbon (AC) was synthesized from rice husks using the chemical activation method with KOH, NaOH, a combination of (NaOH + Na2CO3), and a combination of (KOH + K2CO3) as the chemical activating reagents. The activated carbon with the highest surface area (around 2000m2/g) and high porosity, which allows the absorption of a large number of ions, was applied as electrode material in electric double layer capacitors (EDLCs). The AC for EDLC electrodes is required to have a high surface area and an optimal pore size distribution; these are important to attain high specific capacitance of the EDLC electrodes. The electrodes were fabricated by compounding the rice husk activated carbons with super-P and mixed with polyvinylidene difluoride (PVDF) at a weight ratio of 83:10:7. AC electrodes and nickel foams were assembled with potassium hydroxide (KOH) solution as the electrolyte. Electrochemical measurements were carried out with a three electrode cell using 6 M KOH as electrolyte and Hg/HgO as the reference electrode. The specific capacitance strongly depends on the pore structure; the highest specific capacitance was 179 F/g, obtained for the AC with the highest specific surface area. Additionally, different activation times, levels of heating, and chemical reagents were used to compare and determine the optimal parameters for obtaining high surface area of the activated carbon.

The characteristics of abrasive wear of the rubber matrix composites filled with nano sized silica particles were investigated at ambient temperature by pin-on-disc friction test. The range of volume fraction of silica particles tested are between 11% to 25%. The cumulative wear volume and friction coefficient of these materials on particle volume fraction were determined experimentally. The major failure mechanisms were lapping layers, deformation of matrix, ploughing, deboding of particles and microcracking by scanning electric microscopy photograph of the tested surface. The cumulative wear volume showed a tendency to increase nonlinear with increase of sliding distance. As increasing the silica particles of these composites indicated higher friction coefficient.

The main cause of building fire fatalities occur in the combustible material heat, smoke and toxic gases are. Building interior decoration, etc., especially as much of the harmful substances generated during combustion, and, used in domestic architecture wallpaper, ceiling, and other plastics, built-in foam insulation also analyzed recognition of fire hazards approach to test the conkalrorimiteo test, choedaeyeolbangchulryul through, chongbal heat, mass loss rate, generates carbon monoxide gas hazard ratio tests, analysis and evaluation rigid foam index testing the toxicity of hazardous material generated by performing a gas clean up and assess the material test results, the minimum order to provide data to quantify the risk of fire. Ensure fire safety of building materials, composite materials in order to test the various risk factors could be considered organic to the introduction of testing and evaluation is needed urgently.

In this study, the property of crack growth in structural steel is investigated according to length and angle of crack at the analysis result of model. Strain energy, deformation and stress obtained by finite element analysis are compared with various configuration of crack. Stress intensity factors as fracture toughness are calculated by the basis of strain energy, deformation and stress. As there are almost no errors by comparing stress intensity factors with those from the standard formula, these calculated factors can be confirmed in order to be applied at real structure. In case cracks or holes at structure are existed, the fatigue damage possibility can be examined by use of this study result.

Developing proper reduction strategies of indoor radon which have been an important issue in Korea requires proper information on source characteristics a phosphate gypsum board which is a common building material used for inter-wall thermal protection in Korea could be a major source of indoor radon level. This study evaluated the correlation between indoor radon concentration and the attribution of gypsum board content in building materials. In this study we valuated indoor/outdoor radon from 58 facilities selected based on the information availability of gypsum content in the building material across 8 different cities in Korea. Our results showed that indoor radon concentrations were 2 to 3 times higher than outdoor but those results were not significantly attributed from gypsum contents in the building material. Indeed, phosphate content in gypsum board did not significantly play a role in indoor radon level variations. It is concluded that physical environmental condition such as temperature, relative humidity, radon exhalation rate out of each building materials, as well as pathway from external sources (e.g., soil) needs to be identified to develop indoor radon reduction strategies.

전도성 고분자는 고분자가 갖는 높은 투과도와 화학적 구조에 의한 전도성 특성, 좋은 가공성, 낮은 가격과 같은 이점 때문에 전자산업, 특히 디스플레이 재료 개발 분야에서 그 응용에 대한 연구가 활발히 진행되고 있다. 전도성 고분자는 산화환원에 의해 다른 상태의 구조를 갖게 되는데, 이때 색변화, 전도도가 변하게 된다. 따라서 이러한 특징을 이용하여 전도성 고분자의 직접적인 색변화를 이용한 전기변색 디스플레이와 전도성 고분자가 갖는 전기전도도를 이용한 디스플레이 재료들의 연구가 이루어지고 있다. 전도성 고분자는 그 종류마다 다른 전도도를 갖게 되는데, 이는 그 고분자를 이루는 물질에 의해 결정되기 때문이며, 또한 doping level, dopant, 중합방법에 따라 전도도의 조절이 가능한 특징이 있다. 최근 전도성 고분자 응용 분야의 대표적인 선도 연구로는 전기변색 디스플레이, 대전방지, 높은 전도도를 이용한 투명전극 응용 등이 있다.

Shear test on hollow-core slabs that using board-type lightweight materials is performed. Lightweight materials are positioned in the slabs, it separate into two parts vertically. It is possible that each parts act independently and the concrete columns, in the middle of slab, can resist this action. Thus we have to check horizontal shear force on part-column connection besides vertical shear force. Also effective cross-sectional area shear force which is considered by existing study is checked.

PURPOSES: The performance of tack coat, commonly used for layer interface bonding, is affected by application rate and curing time. In this study, bonding strength tests were performed according to the application rate and curing time of asphalt emulsion. Based on finding from this study, optimum application rates and curing times are proposed. METHODS: In order to investigate bonding characteristic of asphalt emulsion, tests were performed on both asphalt concrete pavement and portland concrete pavement. Also, asphalt emulsions were tested at the application rate of 0, 0.2, 0.4, 0.6, and 0.8l/m2 and at the curing time of 0, 0.5, 1, 2, and 24 hours. Pull-off test and shear bonding strength test, which commonly used for bonding strength measurement of asphalt emulsion, were adopted for this study. To assess field performance under different testing condition, asphalt emulsions were applied to in-service pavement. Throughout coefficient of determination analysis between material index properties from asphalt emulsion and mechanical response from bonding strength tests, performance correlativity was analyzed. RESULTS: Test results show that optimum application rate for asphalt overlay on asphalt concrete pavement (AOA) and asphalt overlay on concrete pavement (AOC) was 0.4~0.5l/m2 and 0.3~0.5l/m2, respectively. According to the curing time increment, tensile strength and shear strength of AOC were increased to 22~44% and 20~39%, respectively. AOA case also show strength increment in tensile strength (42%) and shear strength (9%). We tested the applicability of tack coat materials at the field sites, and our findings demonstrated that the bonding (for D and E) and rapid curing (for B, C, and D, E) performances were superior than others. Among material index properties, there was a high correlation between penetration ratio and bonding strength test result. CONCLUSIONS : Result show that interlayer bonding strength was affected by asphalt emulsion type, application rate and curing time. AOC required slightly higher application (0.1l/m2) than AOA. Both AOA and AOC cases show higher strength at longer curing time. Up to 2hours of curing, rapid strength increments were observed, but strength increment ratio was decreased after 2hours of curing. From the observed correlation between penetration ratio and bonding strength, it is expected that penetration ratio can be used as one of important factors affecting bonding strength analysis.

PURPOSES : As a research to develop a cement treated base course for an airport pavement which can enhance its drainage, this paper investigated the strength, infiltration performance and durability of the pervious concrete with respect to maximum coarse aggregate sizes and compaction methods. METHODS : This study measured compressive strength, infiltration rate, continuous porosity and freeze-thaw resistance of pervious concrete specimens, which were fabricated with five different compaction methods and different maximum aggregate sizes. In addition, in order to reduce the usage of Portland cement content and to enhance environment-friendliness, a portion of the cement was replaced with Ground Granulated Blast Furnace Slag (GGBS). RESULTS: Compressive strength requirement, 5 MPa at 7 days, was met for all applied compaction methods and aggregate sizes, except for the case of self-compaction. Infiltration rate became increased as the size of aggregate increased. The measured continuous porosities varied with the different compaction methods but the variation was not significant. When GGBS was incorporated, the strength requirement was successfully satisfied and the resistance to freezing-thawing was also superior to the required limit. CONCLUSIONS: The infiltration rate increased as the maximum size of aggregate increased but considering construct ability and supply of course aggregate, its size is recommended to be 25mm. With the suggested mix proportions, the developed pervious concrete is expected to successfully meet requirements for strength, drainage and durability for cement treated base or subbase course of an airport pavement.

現代腦科學的研究證明，通過科學分析漢字組成，以及用字謎、詞謎、動作等形式，我們完全可以加深對漢字的認識和記憶。更重要的是，這類研究能啟發我們的智力，並可大幅提升我們對中國語文學習的興趣。我的小團隊已自行開發了《漢字部件分類表》、《漢字分類總表》、《同音字/詞串聯手冊》、《唱歌學漢語》、《看好電影•學好普通話》、《電腦打字自學普通話》、《商務漢語語文知識表》、《商務漢語讀本》等學習材料， 將來並會增添《商業應用中國語文》、《商務溝通技巧》這兩本書，從而在國際層次跟中國政府考試中心的《漢語四六級綜合應用測試》配套，為推動漢字與漢字教育作出貢獻。論文會用多個不同層次的實例去說明有關的語文概念，包括在高層次用中國古訓和現代偉人語錄作為漢字文化的示範，同時也會提一下《漢字宮》和《中華字經》 等別人開發的材料。

针对在非汉语语境下汉语汉字教学面临的挑战，我们编写了一系列个性化、生活化、分类化教材来应对海外学生的不同需求。这套教材的主要特点是：词汇按照功能分类、词汇按照难易程度划分、模块式教材、生活化词汇、个性化教学。我们依据海外汉语教学先听说， 后读、写的实践基础，把教学任务纵向分为：听说、读、写三大支柱，再横向把教学任务根据功能需要粗分为20大篇，同时再细分为若干类，再根据难易程度分为初、中、高三个级别，这样纵横交错就形成教学板块。在每个小的教学模块里，我们先从词汇入手，集中学习增加词汇，然后再扩展为句子句式的掌握，短文段落的说读。同时根据海外学生的特点，进行不同模块间的转换，以掌握进度，巩固学习效果。

수증기 투과는 용이하게 하면서 Dimethyl methylphosphonate (DMMP)에 대한 방호성능을 부여하는 선택투과성 능을 가지도록 고안된 몇가지 복합막을 제조하였다. 선택투과막 재료는 폴리비닐알코올 고분자를 기반으로 염기성 작용기를 가지는 기능성 고분자를 포함하도록 하였다. 이들 재료를 사용하여 화생방호성능을 보유한 차세대 소재로서의 가능성을 확인 하기 위하여 선택투과능을 평가하였다. 시험한 결과, 폴리비닐알코올/폴리에틸렌이민 소재가 우수한 수증기 투과성능(2,200 ~ 2,900 g/m 2 /day) 및 DMMP 증기 방호성능(47 g/m 2 /day)을 가지는 것을 확인하였다.

Aphanizomenon flos-aquae는 시아노박테리아 일종이며 anatoxin-a, saxitoxin, neosaxitoxin 등의 독소를 생산할 수 있어 국내에서는 식품원료로 사용이 금지되어있다. 전통적으로 시아노박테리아는 사상체 넓이, 세포 크기, 분열방법, 세포형태, 가스주머니의 존재유무 등의 형태학적 특징에 의한 분류가 가능하다. 그러나 가스주머니 혹은 무성 포자와 같은 특징은 주변 환경 또는 생장조건에 따라 차이가 있으며 경우에 따라 소실되기도 한다. 따라서 PCR에 의한 Aph. flos-aquae를 함유하는 기능식품을 검출할 수 있는 분석법을 개발하였다. 프라이머를 설계하기 위하여 유전자은행(www.ncbi.nlm.nih.gov)에 등록되어있는 Aph. flos-aquae, 스피루리나의 16S rRNA 염기서열을 이용하였으며, 비교 및 분석에는 BioEdit ver. 7.0.9.0 프로그램을 사용하였다. 최종적으로 클로렐라, 스피루리나, 녹차, 시금치로부터 Aph. flos-aquae를 검출할 수 있는 AFA-F1/AFAR1 (363 bp) 프라이머를 최종 선정하였다. 그리고 상기 프라이머는 Aph. flos-aquae가 각각 1% 함유 되도록 제조된 클로렐라, 스피루리나 제품에서 모두 혼입여부의 확인이 가능함을 확인하였다.

본 연구에서는 분자생물학적 방법을 통한 알레르기 유발 원재료 확인을 위해 PCR방법의 최적 조건을 구축하였 다. 가공식품에서 알레르기 원료성분 확인을 위하여 200bp 내외의 PCR 산물을 생성할 수 있는 종특이 프라이머를 설계하거나 선행연구사업 결과를 활용하였다. 대상 원료로는 국내 식품알레르기 표시대상인 난류, 우유, 메밀, 땅 콩, 대두, 밀, 고등어, 게, 새우, 돼지고기, 복숭아 및 토마 토와 제외국에서 알레르기 유발 성분으로 규정하고있는 아몬드, 참깨를 포함하여 총 14종을 대상으로 하였다. 특이 프라이머를 사용하여 PCR 한 결과 난류, 우유, 메밀, 땅콩, 대두, 밀, 고등어, 게, 새우, 돼지고기, 복숭아, 토마토, 아몬드 및 참깨로부터 각각 281, 131, 138, 120, 118, 127, 211, 174, 231, 138, 174, 132, 103 및 220bp의 특이 밴드를 확인하였으며 상호간의 비특이적 밴드는 검출되 지 않았다. 본 연구에서 확립한 알레르기 유발 원재료 검출법은 식품의 부정확한 표시나 가공식품의 제조과정 중 알레르기 유발물질의 비의도적 혼입 등으로부터 소비자를 보호하고 향후 수출 제품에 있어서 정확한 알레르기 유발 원재료 표기에 활용이 가능할 것으로 판단된다.

본 연구는 추수감사절에 지역별로 교회 강단장식에 사용된 표 현 소재의 사용빈도와 장식에 사용되는 색채의 흐름을 파악하기 위하여 서울, 인천, 대전, 경기도, 충남, 전북, 경남, 강원도의 8 지역의 교회를 직접 방문하여 조사하였다. 소재의 사용빈도는 절 화류, 절엽류, 절지류, 과일 및 채소류, 부소재류로 나누어 조사 하였다. 절화류의 경우 소국외 18종류를 사용하여 장식하였는데 이중 소국이 32곳(80%)으로 가장 많이 사용하였으며, 특히 경 기도와 경남 지역은 5곳(100%) 모든 교회에서 사용하여 장식하 였다. 절엽류의 경우 엽란이 뒷받침 소재로서 전국적으로 15곳 (37.5%)에서 가장 많이 이용되었고, 다른 품종은 전체적으로 사 용빈도는 적지만 다양한 소재를 장식에 활용하고 있는 것을 알 수 있었다. 경기도와 강원지역에서는 엽란 대신 편백을 사용하였 다. 11월에 생산되는 열매의 절지류가 다양하게 많이 활용되고 있었는데, 그중 남천이 전국적으로 21곳(25.5%)에서 활용되어 가장 많이 사용되어지고 있었다. 추수감사절에 맞게 가을에 수확 한 과일 및 채소류가 가장 다양하게 사용되고 있었는데, 그 중 감(Diospyros kaki)의 사용빈도가 가장 높았고(100%) 사과, 배 등 매우 다양한 소재를 장식에 활용한 것을 볼 수 있었다. 특 히 충남에서 가장 다양한 36종류를 사용하였고 강원도에서는 다 른 지역에 비해 옥수수를 많이 사용하였다. 색채 선호 경향을 보면 가을철 잎이 가지는 색의 3속성을 달리하여 계절의 감각을 표현하였으며 절지류 열매의 색채와 어울리는 빨강, 노랑, 녹색이 8지역 모두 40곳(100%)으로 높은 사용빈도를 나타냈으며, 주황 이 39곳(97.5%)으로 빨강과 노랑의 절지류 열매에 어울리는 장 식 색으로 많이 활용되어지고 있었다. 하지만 청록, 파랑, 남색 의 사용빈도는 매우 낮은 것으로 나타나 가을에 주는 느낌과 대 조되는 색이라는 것을 알 수 있었다. 지역별 교회 장식의 소재 별 선호 경향을 보면 절화류와 절엽류 등을 사용하여 장식을 보 다 풍성하게 도와줄 수 있는 과일 및 채소류의 소재가 다양하게 사용하고 있음을 알 수 있었다.

PURPOSES: This paper aims to give a guideline and the way to apply the advanced composite materials theory to the road structures with different cross sections to the practicing engineers. METHODS: To simple but exact method of calculating natural frequencies corresponding to the modes of vibration of road structures with different cross sections and arbitrary boundary conditions. The effect of the D22 stiffness on the natural frequency is rigorously investigated. RESULTS: Simple method of vibration analysis for calculating the natural frequency of the different cross sections is presented. CONCLUSIONS: Simple method of vibration analysis for calculating the natural frequency of the different cross sections is presented. This method is a simple but exact method of calculating natural frequencies of the road structures with different cross sections. This method is extended to be applied to two dimensional problems including composite laminated road structures.

PURPOSES: Current theories for composite structures are too difficult for design engineers for construction. The purpose of this paper is to demonstrate to the practicing engineers, how to apply the advanced composite materials theory to the road structures. METHODS: Some laminate orientations have decreasing values of D16, B16, D26 and B26 stiffnesses as the ply number increases. The plate aspect ratio considered is from 1 to 5. In order to study the effect of Mx on the equilibrium equations, two cases are considered. Mx term is considered or neglected. RESULTS: Most of the road structures have high aspect ratios, for such cases further simplification is possible by neglecting the effect of the longitudinal moment terms. CONCLUSIONS: Most of the road structures have plate aspect ratios higher than 2. It is concluded that, for all boundary conditions, neglecting the longitudinal moment(Mx) terms is acceptable if the aspect ratio (a/b) is equal to or higher than 2. This conclusion gives good guide line for design of the road structures.

Food contact packaging material should be stable and non-reactive with the food that it is in contact with, and must promote the safety of food. However, for a number of years, there has been evidence that indefinitely small amounts of chemicals could migrate or leach from food packaging materials into the foods they hold. The chemistry and toxicity of such leachates are well-known and documented; and there is a growing concern over the matter among the general public. In addition, food regulatory agencies are imposing more stringent regulations on the maximum allowable amounts of known leachates into foods in recent years. The majority of toxicity studies have revealed that trace amounts of leachates pose no immediate health problems in humans. However, studies on the effects of long-term exposure or synergistic/cumulative toxicity are still lacking. The present review provides an overview of the chemical nature and toxicity of certain leachates from various types of food contact packaging materials that are in wide use.