Multiwall carbon nanotubes (MWCNT) with two different (L/D) aspect ratios (7±2 μm/140±30 nm and 0.5–2 μm/8–15 nm) were surface treated using nitric acid (HNO3) and polyethyleneimine (PEI) prior to their deposition on carbon fibers (CF). Before the hierarchical reinforcement with CF-MWCNT, the CFs were treated with 3-glycidoxypropyltrimethoxysilane, a coupling agent (Z6040) and with poly(amidoamine) (PAMAM) a dendrimer containing an ethylenediamine core and amine surface groups. The MWCNT were deposited on the CF using two methods, by electrostatic attraction and by chemical reactions. The changes in the CF surface morphology after the MWCNT deposition were analyzed using SEM, which revealed a higher density and uniform coverage for the PAMAM-treated CF and the short MWCNTs. The interfacial adhesion of the composite materials was evaluated using the single fiber fragmentation technique. The results indicated an improvement in the interfacial shear strength with the addition of the short-MWCNTs treated with acid solutions and grafted onto the surface of the CF fiber using electrostatic attraction.

PURPOSES : The purpose of this study is to verify the effects of fiber grid reinforcement on the thickness reduction of asphalt pavement. Test sections were constructed on the national highway to evaluate the structural capacity of asphalt pavement with the reinforced fiber grid and normal asphalt pavement. METHODS: Falling Weight Deflectometer (FWD) tests were performed to measure the structural capacity of test sections. The loads of the FWD test are 4.1 ton, 8.0 ton, 10.0 ton, and loaded twice, respectively. The test sections consist of a reference asphalt pavement section, an asphalt pavement section reduced with a 5-cm base layer thickness, and a fiber grid reinforced asphalt pavement section reduced with a 5-cm base layer thickness. In addition, strain data was collected using strain gauges installed in the test sections. RESULTS: The results of the FWD tests showed that the deflections of the pavement section reinforced with the fiber grid was reduced by about 14% compared with that of the reference asphalt pavement section. The strain at the bottom of the asphalt surface layer of the pavement section reduced to a 5-cm base thickness and reinforced with a fiber grid was similar to that at the bottom of the asphalt layer of the reference asphalt pavement. CONCLUSIONS : The results of the FWD and strain tests showed the possibility of the pavement thickness reduction by reinforcement with a fiber grid.

본 연구에서는 열분해잔사유(Pyrolysis Fuel Oil, PFO)를 이용한 Pitch계 활성탄소섬유를 제조하였다. 제조한 Pitch안정화 섬유의 탄화 및 활성화 온도를 850, 880, 900 ℃로 달리하여 각각 다른 샘플의 기공형성에 대한 영향을 알아보기 위해 BET 와 SEM을 이용하여 비교 분석하였다. 세 가지 샘플 ACF850, ACF880, ACF900를 분석한 결과 ACF880의 비표면적과 미세 기공표면적이 각각 1,420 m2·g-1, 1,270 m2·g-1으로 가장 높았으며, 외부비표면적과 BJH흡착누적공극표면에서 가장 낮은 중기공표면적이 도출되었다. 또한 N2가스 등온흡착곡선을 분석한 결과, 미세기공의 분포가 균일한 것을 확인할 수 있었다. ACF880은 흡착률 및 흡착속도에서도 가장 높은 결과값을 보이며, 흡착속도는 미세기공표면적과 비례하며 중기공표면적과 반비례함을 알 수 있었다. 제조한 Pitch계 활성탄소섬유를 라돈 연속측정방법을 통해 48시간 동안 측정한 결과 샘플 모두 라돈 흡착성능을 보였다. 제 조한 샘플 중 ACF880이 34.0%로 가장 높은 흡착률을 보였으며, ACF850이 29.5%로 가장 낮은 흡착률을 나타내었다. 이는 비표면적이 높을수록 흡착률이 높아지는 것을 알 수 있었다. 이를 선형회귀선 기울기로 환산하여 흡착속도로 확인한 결과 ACF880이 -1.89로 가장 빠른 것을 확인하였으며, ACF900이 -1.48로 가장 낮은 흡착속도를 보여 미세기공표면적이 높을수 록, 중기공표면적이 낮을수록 흡착속도가 증가하는 것을 알 수 있었다.

This study investigated the stress-related metabolites and hormones in blood and compared the muscle structure to identify the reason for blood splash in Hanwoo beef. Five slaughter houses were selected based on the region (Seoul, Gimhae, Jungbu, Naju, and Goryung) and a previous blood splash record. In total, three-hundred eighty blood samples (n=380) and forty-two muscle tissues (n=42) of control and blood splash Hanwoo beef were collected during the slaughter process and beef grading. Blood metabolites were analyzed including glucose, lactate, creatinine, urea-N, and hormones such as cortisol and thyroxin. Muscle fiber, fiber bundle, and capillary wall thickness were measured under microscope. The concentrations of blood glucose, lactate, and urea-N were not significantly different between the control and the blood splash samples. Cortisol and thyroxin levels were not significantly different in both samples. In contrast, the creatinine level was significantly increased (p<0.05) in the blood splash samples. There were also no significant differences observed in muscle fiber, bundles, and capillary wall thickness between the control and the blood splash tissues. In conclusion, blood metabolites, hormones, and muscle fiber showed no differences between the control and the blood splash animal. However, increased creatinine levels may be used as an indicator for identifying blood splash prior to slaughter in Hanwoo.

The pultruded fiber reinforced polymer plastic (PFRP) is one of the most actively studied composite materials for the structural member in construction industries. In domestic design process, the PFRP member is designed as an isotropic material having only longitudinal material properties for simplicity, because it is too complex to consider orthotrophy of PFRP perfectly. In this study, three cases of buckling analysis of PFRP plate is conducted theoretically and numerically. First, the PFRP plate is considered as an orthotropic material. Second, the PFRP plate is considered as an isotropic plate having only longitudinal material properties. Third, the PFRP plate is considered as an isotropic plate having geometric mean of longitudinal and transverse material properties. As a result of buckling analysis, a buckling strength of PFRP plate as an isotropic plate having only longitudinal material properties is about 2.21 times larger than that of PFRP plate analyzed as an orthotropic plate. On the other hand, a buckling strength of PFRP plate as an isotropic plate having geometric mean material properties is about 1.19 times larger than that of PFRP plate analyzed as an orthotropic plate. In conclusion, the safety factor of 3 used in domestic design process of PFRP member is no longer applicable due to overestimation of buckling strength of PFRP member which leads to nonconservative design.

본 연구에서는 인체 친화적이고 환경 친화적인 패션제품 소재기획을 위한 기초 자료를 제시하고자 수행되었다. 이를 위해서 4종의 섬유소 소재를 대상으로 염색조건을 달리하여 천연 쪽 염색을 실시하여 색채특성과 색채감성을 평가하였으며, 이러한 특성이 선호도에 미치는 영향을 분석하였다. 쪽 염색된 직물은 모두 중, 저명도와 저채도의 남색(PB)을 구현하였다. 이들 직물의 색채특성은 섬유종류와 염색조건에 따라 유의한 차이를 보였다. 쪽 염색된 직물에 대한 색채감성은 스포티 감성, 클래식 감성, 내추럴 감성 등 3가지 요인으로 분류되었다. 이러한 색채감성은 섬유종류와 염색조건에 따라 부분적으로 유의한 차이를 나타내었다. 또한 쪽 염색 직물의 색채특성과 색채감성 요인 간에는 부분적으로 유의한 상관관계를 보였다. 쪽 염색 직물의 색채 선호도에 영향을 주는 요인으로는 색채감성 요인 중에서 클래식 감성과 스포티 감성, 색채특성에서는 L*값인 것으로 나타났다.

The service life of coal gangue concrete(CGC) strongly depends on the capillary water absorption, this water absorption is susceptible to freeze-thaw cycles. In this paper, the cumulative water absorption and sorptivity were obtained to study the effects of 0, 0.5, 1.0, and 1.5 % steel fiber volume fraction added on the water absorption of CGC. Sorptivity and freeze-thaw tests were conducted, and the capillary water absorption was evaluated by the rate of water absorption(sorptivity). Three prediction models for the initial sorptivity of steel fiber reinforced coal gangue concrete(SFRCGC) under freeze-thaw cycles were established to evaluate the capillary water absorption of SFRCGC. Results showed that, without freeze-thaw cycles, the water absorption of CGC decreased when steel fiber at 1.0 % volume fraction was added, however, the water absorption increased with the addition of 0.5 or 1.5% steel fibers. Once the SFRCGC specimens were exposed to freeze-thaw cycles, the water absorption of SFRCGC significantly increased, and 1.0 % steel fiber in volume fraction added to CGC caused the lowest water absorption, except for the case of the sample without steel fibers added. The CGC with steel fiber at 1.0 % volume fraction performed better. The SFRCGC has a strong response to freeze-thaw cycles. Results also showed that the linear function prediction model is practical in the field of engineering because of its simple form and a relatively high precision. Although the polynomial prediction model presents the highest computation precision among the three models, the complicated form and too many coefficients make it impractical for engineering applications.

In this study, thermal performance test of VMD module was performed, prior to the construction of the demonstration plant using the vacuum membrane distillation　(VMD) module of the capacity of 400 m3/day and to the commercialization of the VMD module. For the thermal performance test, the experimental equipment of capacity of 2 m3/day was constructed. The permeate flux test and thermal performance test according to feed water conditions such as temperature and flow rate were conducted. The VMD module used in the study was manufactured by ECONITY Co., LTD with PVDF hollow fiber membrane. As a result, the Performance Ratio (PR) of the VMD module showed the maximum value of 0.904 under the condition of feed water temperature of 75℃ and flow rate of 8 m3/h. PR value of the VMD module using PVDF hollow fiber membrane showed linearly increasing relationship with feed water temperature and flow rate. Also, The permeate flux of the VMD module was analyzed to have maximum value of 18.25 LMH and the salt rejection was 99.99%.

Introduction The current fashion industry has been overrun with fast fashion products in the last couple of decades. Consequently, it has become one of the most environmentally degrading industries worldwide, and is plagued by social and economic inequalities (Fletcher, 2013). The fast fashion apparel industry produces pollution and waste; and wearers are exposed to hazardous materials. The fast pace of the fashion industry has also led to unsafe working conditions that can result in detrimental influence on workers as in the 2013 Rana Plaza collapse in Dhaka, Bangladesh. Furthermore, the individuals responsible for making the fast fashion products often live in underdeveloped countries and are paid below national minimum wage (Niinimaki, 2013). In contrast, the sustainable fashion industry aims to produce safer, cleaner, and more impactful apparel. A part of the growing sustainable apparel industry is slow fashion, which emphasizes creating fashion products at a less-intensive pace with environmentally-minded techniques. Slow fashion movement is an emerging trend within the fashion industry that counteracts the harms of fast fashion. The term „slow fashion‟ was first used by Kate Fletcher and shares several characteristics with slow food, from which the slow fashion movement got much of its inspiration (Cataldi, Dickson, & Grover, 2010). Slow fashion is thought to represent a blatant discontinuity such as a break from the values and goals of fast (growth-based) fashion (Fletcher, 2013). Slow fashion attempts to remedy the various negative economic, social, and environmental global impacts of the current fast fashion system. The purpose of this study was to analyze the material-oriented trends of representative fast fashion and slow fashion brands toward the development of sustainable fashion. This study aimed to answer the following questions: 1) By what efforts in terms of material usage do the fast and slow fashion brands promote sustainable fashion? and 2) How do these efforts influence apparel manufacturing as sustainability practices and consumers‟ purchase intentions? Backgrounds Moore and Fernie (Moore & Fernie, 2004, p. 31) defined fast fashion as “various strategies to respond commercially to the latest fashion trends”. Fast fashion brands, such as H&M, Forever 21, and Zara, use a combination of quick response and enhanced design techniques to quickly design, manufacture, and stock trendy apparel and accessories that consumers can purchase at an affordable price (Cortez et al., 2014). The manufacturers of fast fashion brands struggle to provide innovative merchandise in their preferred production timetable (Cortez et al., 2014). In such an overloaded manufacturing process, the apparel industry has experienced increased pollution and hazardous work environments. Slow fashion is defined as “a philosophy of attention that is sensitive to environmental and societal needs and to the impact production and distribution have on society and the environment” (Karaosman, Brun, & Morales-Alonso, 2016). Antanaviciute and Dobilaite (2015) report that the slow fashion industry is sustainable and seeks a greater purpose than making profit, and is thus characterized with promoting fair economic, environmental, and social systems within the fashion cycle. In the slow fashion movement, the materials used to produce garments are environmentally friendly. Sustainable fashion is achieved when available materials are used to their ultimate potential; waste materials are utilized; the products are recycled; and a second life for the fashion products is planned (Sharda & Mohan Kumar, 2012). In addition, sustainable fashion uses biodegradable materials such as organic cotton, polylactic acid, and other biopolymers etc. (Fletcher, 2013). In the production phase, garments workers who produce sustainable fashion products are paid a living wage, unlike their counterparts who work for less than a dollar a day in the fast fashion industry. Throughout the slow fashion supply chain, reducing the speed at which the products are produced and consumed is emphasized. Slowing down the production phase results in end products of better materials, with more material-construction input-time, and longer-lasting overall final product, as compared to typical fast fashion items. Case study This study was conducted based on a case study. We analyzed the sustainability practices in aspect of fiber materials of two representative brands: a fast fashion, Zara and a slow fashion, People Tree. Several resources were used to collect the information necessary for the case study. The primary resources were academic articles, reports, and brochures from companies‟ websites. The information on both companies was very useful to understand their products and sustainability practices as a fast fashion and a slow fashion brand. Zara is a ready-to-wear fast fashion retailer based in Spain, which was created by Rosalia Mera and Óscar Pérez Marcote in 1974. Since its creation, the fast fashion retailer has built a reputation for manufacturing and stocking on-trend clothing at the customer‟s demand. The company sends small shipments year-round to stores and subsequently monitors the customers‟ reactions by adjusting the store inventory. The retail giant has employed over 10,000 employees and is a private company that, according to the Business of Fashion, was worth $16.7 billion in 2013 (Hansen, 2012). Zara is known as affordable luxury (Gamboa & Goncalves, 2014) for its on-trend imitations of high-end clothing pieces that are inexpensive. The average Zara consumer is young with an age range of 18 to 24 years and female (Gamboa & Goncalves, 2014). Zara was chosen for this case study based on its unique and successful fast fashion business model. Zara has been criticized for numerous violations in manufacturing practice, including a lack of hygiene and safety in its Argentinian factories. The workers‟ rights NGO La Alameda, alleged that the working conditions consisted of no breaks and poorly lit and unventilated conditions (Crotty, 2013). The company compensated the workers and was forced to pay $530,000. People Tree is considered as a pioneer in the slow fashion movement and sustainable fashion. The company has implemented many measures to increase its economic, social, and environmental sustainability. People Tree was the first fashion brand to develop an integrated supply chain for organic cotton from the farm to the final product. Furthermore, they were the first organization to achieve a Global Organic Textile Standard certification. They source their yarns, fabrics, and accessories locally, as well as choose natural and recycled products over the toxic, synthetic, and non-biodegradable materials typically found in fast fashion products. The People Tree producer group is comprised of over 4,560 artisan producers, which includes hand weavers, hand knitters, embroiderers, tailors, and group leaders. They allow local individuals to produce and create incredibly unique products, thus generating livelihoods and incomes for these individuals who typically reside in very rural areas. Zara uses a variety of synthetic and organic fibers and textiles in its clothing. Zara partners with a company called Lenzing to source recycled polyester, cotton, and wool when available, and then donates any extra textiles not used in manufacturing products. Zara prioritizes using organic cotton and recycled materials. Organic cotton is grown and manufactured without harmful pesticides. Zara has become one of the biggest users of organic cotton, which is a part of their Join Life campaign and in collaboration with the Better Cotton Initiative (Inditex Annual Report, 2016). Zara also uses three types of rayon in its products: Modal, Viscose, and Lyocell. These materials are made from cellulose fibers, which take longer to harvest and manufacture than cotton. People Tree does not use polyester in its products, and most of its clothing is made from organic cotton and wool. It uses 100% fair-trade certified organic cotton that is certified by Soil Association (People Tree Seventh Biennial Social Review, 2011-2012). In addition to cotton and wool, it uses a fiber called “Tencel,” which is made from wood pulp. Tencel is a Lyocell product, also made from cellulose fiber, which is stretch-resistant and highly versatile. Zara uses both synthetic and organic fibers; whereas, People Tree uses organic fibers in the manufacturing of products. Lyocell is one of the most revered sustainable fibers currently on the market. Lyocell is a cellulosic fiber, specifically derived from wood pulp, normally eucalyptus (Fletcher, 2013), beech, and pine (Gordon & Hill, 2015). In a typical process, the wood pulp is dissolved in a solution of amine oxide, a solvent, which is then spun into fibers; subsequently, the solvent is removed from the fibers through a washing process (Fletcher, 2013). The manufacturing process recovers 99.5% of the solvent and the solvent is recycled back into the process (Fletcher, 2013). The solvent is non-toxic, non-corrosive, and all effluent is non-hazardous (Fletcher, 2013). Lyocell has many other environmental benefits such as complete biodegradability (six weeks in an aerated compost heap), and of renewable raw material (eucalyptus has a fast-growing cycle and reaches full maturity in seven years). No bleaching is used prior to processing the fiber, thus reducing chemical, water, and energy consumption in the dyeing process; hence, Lyocell is considered as a “very clean” fiber (Fletcher, 2013). While Lyocell is considered a very sustainable product, its production is energy intensive. However, due to recent research, the amount of energy used to make Lyocell has begun to decrease (Fletcher, 2013). Lyocell is also known by its brand name, Tencel (Gordon & Hill, 2015). Companies such as People Tree have begun to use products like Tencel in their everyday-clothing production. People Tree‟s “Our Tencel” collection is produced by Creative Handicrafts, a social enterprise working to actively empower disadvantaged women of the slum communities of Mumbai through economic independence. Like every producer of People Tree‟s clothing or Tencel products, Creative Handicrafts works to provide fair pay and safe treatment for all their workers. They also work to improve the lives of those employed by Creative Handicrafts. People Tree is currently using their “Our Tencel” collection to upskill the workers, making them qualified for higher paying and more difficult jobs should they choose to leave Creative Handicrafts. They aim to provide workers with a greater range of fabrics that they can work with for future client‟s needs. This provides the workers with greater business opportunities. The slow fashion brand‟s attributes attract ethical consumers. The ethical consumer considers the impact of consumption in terms of environmental and social responsibilities (Barnett et al., 2005). The likeliness of ethical consumer‟s purchasing or willing to purchase a slow fashion product depends on the customer‟s level of involvement. A consumer with high involvement who is willing to purchase the product at a higher price, is not attracted to mass fashion trends, and shows intent to purchase an apparel product for environmental reasons (Jung & Jin, 2016). McNeil and Moore (McNeil & Moore, 2015) found correlations between concern levels for both environmental and social wellbeing and consumer‟s intentions towards sustainable apparel. Similarly, it is possible to predict the preference of ethical consumers to purchase a fast fashion product if made of sustainable fiber materials. Conclusions We analyzed the material-oriented trends of representative fast fashion brand, Zara, and slow fashion brand, People Tree, toward development of sustainable fashion. The kinds of materials used by each brand in manufacturing fashion products, and recent efforts in sustainable practices of both fashion brands were analyzed. The results indicated that the fast fashion brand, Zara has begun to incorporate sustainable fibers such as organic cotton into their products, and the slow fashion brand, People Tree uses more sustainable fibers such as Tencel and organic cotton for its garments and other products. The efforts involved in the trends of fast and slow fashion brands toward sustainable fashion were anticipated to attract ethical consumers‟ purchase intentions. The current findings suggested that new technology offers innovative manufacturing processes producing more eco-friendly products, less waste, and less pollution, which begins to mitigate the negative environmental effects of the traditional fast fashion industry. Implications and limitations This study was intended to analyze the efforts involved in the production of fast fashion and slow fashion brands in aspect of fiber materials, toward the overall goal of sustainable practices. This study may be useful to designers, manufacturers, and retailers who hope to better understand the trend of sustainable practices of both fast and slow fashion brands. Since ethical consumers presumably prefer sustainable products, this study may help designers, manufacturers, and retailers establish optimized strategies tailored to such trends. This study has a limitation due to selection of a small number of brands, which prevents the generalization of the results to all fast and slow fashion brands.

The compressive strength and electrical resistance of pitch-based carbon fiber (CF) in cementitious materials are explored to determine the feasibility of its use as a functional material in construction. The most widely used CFs are manufactured from polyacrylonitrile (PAN-based CF). Alternatively, short CFs are obtained in an economical way using pitch as a precursor in a melt-blown process (pitch-based CF), which is cheaper and more eco-friendly method because this pitch-based CF is basically recycled from petroleum residue. In the construction field, PAN-based CFs in the form of fabric are used for rehabilitation purposes to reinforce concrete slabs and piers because of their high mechanical properties. However, studies have revealed that construction materials with pitch-based CF are not popular. This study explores the compressive strength and electrical resistances of a cement paste prism using pitch-based CF.

To aid in the development of a food nutrient database that provides the dietary fiber composition of eat-out Korean foods, we determined the total dietary fiber (TDF) content in the eat-out Korean foods Muchim, Bokkeum, and Guk (Tang) using a dietary fiber autoanalysis instrument. A total of 59 samples were collected from Gangwon-do, Gyeonggi-do, Gyeongsangdo, Seoul, Jeonla-do, and Chungcheong-do. First, among 14 samples of Muchim, the TDF content of Kkaennip namul, Goguma-julgi-namul, and Dallae-namul (4.33~6.24, 3.16~5.07 and 3.70~4.99 g/100 g, respectively) was higher than the other types of Muchim. There was no significant difference in TDF content of Muchim (p>0.05) among locations. Among 13 samples of Bokkeum, the TDF content of Pyogo-beoseot-Bokkeum (4.77~6.66 g/100 g) and Miyeok-julgi-Bokkeum (4.16~7.47 g/100 g) was higher than the other types of Bokkeum. The TDF content of Pyogo-beoseot-Bokkeum in Gyeongsang-do was the lowest and the TDF content of Miyeok-julgi-Bokkeum in Gangwon-do was the highest (p<0.05). The TDF content of spinach soybean paste soup (1.34~2.21 g/100 g), Dakgogi-yukgaejang (1.61~2.45 g/100 g), duck stew (1.25~2.80 g/100 g) and spicy yellow croacker stew (1.70~2.27 g/100 g) were higher than the other types of Guk (Tang). There was no significant difference in TDF content of Guk (Tang) among locations (p>0.05).

본 논문에서는 합성단면을 갖는 구조물의 극한 거동 해석에서 요구하는 재료 및 기하학적 비선형 해석을 수행하기 위한 보 요소를 제시하였다. 제안된 요소는 기하학적 비선형성을 효과적으로 모사할 수 있는 co-rotational 정식화를 통해 도출되 었으며, 다양한 합성단면의 저항성능을 재현할 수 있도록 화이버 단면법이 요소의 내력 및 강성을 산정하는데 활용되었다. 제안된 방법을 구현할 수 있도록 해석 프로그램이 개발되었으며, 호장법을 적용하여 최대내력 발생 이후의 연성거동뿐만 아 니라 심한 비선형 응답(snap-through 또는 snapback)까지 추적해낼 수 있도록 하였다. 본 연구에서 제안된 요소 정식화와 해석 프로그램의 정확성을 검증을 위해 몇 가지 수치예제가 수행되었고, 해석결과는 제안된 요소의 정확성과 효율성을 보이 기 위해 3차원 연속체 모델 및 기존 연구의 결과와 비교되었다. 추가로 합성단면을 갖는 골조 구조물에 대한 수치예제를 통 해, 합성단면을 구성하는 재료의 탄성계수 비 및 강도 비에 따른 영향을 분석하였다. 해석결과는 외층 재료의 탄성계수가 증 가됨에 따라 준취성 거동이 나타났으며, 외층 재료의 항복강도가 높을수록 선형 거동하는 기하적 비선형 응답과 유사한 응 답을 보였다.

PURPOSES: The objective of this study is to verify the effect of fiber grid reinforcement on the long-term performance of asphalt pavement overlaid on old concrete pavement by performing field investigation, laboratory test, and finite element analysis. METHODS : The reflection cracking, roughness, and rutting of fiber grid reinforced overlay sections and ordinary overlay sections were compared. Cores were obtained from both the fiber grid reinforced and ordinary sections to measure bonding shear strength between the asphalt intermediate and asphalt overlay layers. Fracture energy, displacement after yield, shear stiffnesses of the cores were also obtained by analyzing the test results. Finite element analysis was performed using the test results to validate the effect of the fiber grid reinforcement on long-term performance of asphalt pavement overlaid on the old concrete pavement. The fatigue cracking and reflection-cracking were predicted for three cases: 1) fiber grid was not used; 2) glass fiber grid was used; 3) carbon fiber grid was used. RESULTS : The reflection-cracking ratio of fiber grid reinforced sections was much smaller than that of ordinary sections. The fiber grid reinforcement also showed reduction effect on rutting while that on roughness was not clear. The reflection-cracking was not affected by traffic volume but by slab deformation and joint movement caused by temperature variation. The bonding shear strength of the fiber grid reinforced sections was larger than that of the ordinary sections. The fracture energy, displacement after yield, and shear stiffnesses of the cores of the fiber grid reinforced sections were also larger than those of the ordinary sections. Finite element analysis results showed that fatigue cracking of glass or carbon fiber grid reinforced pavement was much smaller than that of ordinary pavement. Carbon fiber grid reinforcement showed larger effect in elongating the fatigue life of the ordinary overlay pavement compared to glass fiber grid reinforcement. The binder type of the overlay layer also affected the fatigue life. The fiber grid reinforcement resisted reflection-cracking and the carbon fiber grid showed the greater effect. CONCLUSIONS: The results of field investigation, laboratory test, and finite element analysis showed that the fiber grid reinforcement had a better effect on improving long-term performance of asphalt pavement overlaid on the old concrete pavement.

막여과 생물반응기는 분리막 공정을 기반으로 한 생물학적 고도 하폐수 처리기술이다. 최근, 막여과 생물반응기 내의 고질적인 문제인 생물막오염을 근본적으로 해결하고자 미생물 간의 정족수 감지(quorum sensing)를 차단하는 정족수감지 억제(quorum quenching) 기술을 적용한 연구가 활발히 보고되고 있다. 이 기술을 침지형 중공사막 생물반응기에 적용할 때 중공사막 간격에 따라 막오염과 정족수 감지 억제 효과가 다를 수 있는데, 그러한 효과를 비교한 연구는 없었다. 따라서 본 연구에서는, 정족수 감지 억제 담체를 적용한 침지형 중공사막생물반응기 안에서 막 사이의 간격에 따른 막오염 정도와 막오염 방지 효과를 비교하였다.

본 연구에서는 높은 이산화탄소 분리성능을 가지는 폴리이미드 제조를 위해 3가지 모노머를 이용하여 합성하였다. 합성된 고분자를 비용매 상전이법으로 비대칭 분리막을 제조하기 위하여 고분자의 용해도 지수 추정 값과 비용매 상전이 계수 측정을 통해 용매를 선정하였고, 고분자 용액 점도 측정을 통해 분리막제조를 위한 도프용액 중의 고분자의 함량을 결정하여 질산리튬을 첨가제로 사용하여 최종적으로 분리막을 제조하였다. 제조된 비대칭 분리막은 전자주사현미경(SEM)을 통해 질산리튬과 휘발성 용매 함량에 변화에 따른 모폴로지의 변화를 확인하였으며, 이의 변화에 따른 기체 투과도 변화를 확인하였다. 휘발성 용매 함량이 작을수록 선택도는 유지되면서 이산화탄소 투과도가 증가하는 것을 확인하였다.