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        2.
        2018.10 구독 인증기관·개인회원 무료
        Global climate change and increased international travel have affected the transmission of mosquito-borne diseases. In South Korea, uncommon diseases such as Dengue, chikungunya and Zika virus could be transmitted by potent mediator like Aedes albopictus. In order to cope with the risk of mosquito-borne diseases, rapid mosquito monitoring system is needed. Current mosquito monitoring procedures include installation of outdoor traps-mosquito collection-species classification-analysis of disease detection – upload of information to government research institutes – disease alert. In this process, species classification takes a lot of time, and if we reduce the time, we can cope with the disease outbreak more quickly. In this study, we developed automate species classification system target for 5 mosquito species (Culex pipiens, Cx. tritaeniorhynchus, Ae. albpictus, Ae. vexans, Anopheles spp.) disease vector live in South Korea. After modeling the morphology of each mosquito species, machine learning was carried out using DenseNet (Densely Connected Networks), one of the models of Artificial Neural Network. Using the learned model, we tested the classification of 5 species of mosquitoes and showed the accuracy from 97.35% to 99.48% at the maximum. Future research will focus on increasing the number of identifiable mosquito species and reducing the time spent on species classification. The autonomous classification of mosquito species using Deep Learning technology will contribute to the development of mosquito monitoring system and public health.
        3.
        2018.05 구독 인증기관·개인회원 무료
        As the demand of fossil fuel has been increased, meeting future will be faced with exhausted non-renewable energy generation. In addition, there is a lot of expectation that fossil fuel resources are expected to get depleted in the end of century. Piezoelectric energy harvesting technology has significant advantages over other renewable energy sources such as solar panel, wind and geothermal energy. By using the pressure of vehicles, the piezoelectric energy transforms to electric energy by deformation of paving materials. There are many studies about this theme, only a few researches have been conducted on-site. It means that piezoelectric harvester is not available for roadway. Therefore, it is necessary to make it better a research framework that is available technology of piezoelectric materials and paving materials. The piezoelectric generator is tested before piezoelectric harvester manufacture for roadway. Each piezoelectric generator produces 9.38[mW/cm²] and piezoelectric harvester is manufactured by the number of 85 the piezoelectric generator. This harvester size has 50*20*9cm3 which is considered for wheel path of vehicle. When the chosen vehicle (about 2 ton) pass this harvester, the amount of electric energy is 255[W/m²] under 2[mm] of deformation and 30[km/h] of velocity. In this situation, the gathered energy is multiplied the maximum of voltage and electric current then divide it for the area of harvester. The test result is the temperature difference between the inside and outside after the thermal insulation coating process. When the external surface temperature is increased to 180 degrees, the internal temperature is kept 80 degrees even after about 30 minutes, indicating that the internal materials are protected from heat. In spite of many advantages with piezoelectric harvesting system, it is very hard to fit between roadway and harvester because of pavement damage. Most of paving material has a strong thickness. In this study, instead of asphalt and concrete pavement, the paving material is compound of poly-urethane to protect rutting and damage. To analysis for behavior, test is conducted by 90,000 times of wheel load on the pavement. The red line on the graph is commonly used asphalt pavement and the green one is polyurethane pavement. As it seemed that polyurethane pavement shows that the depth from wheel load is over 5 times better performance compared with asphalt pavement. Construction design is first of all, cutting off asphalt which is established before, then set up the tenth of piezoelectric harvesters, twenty fourth of road markers is installed into the roadway. Before filling up to space with polyurethane materials, wire arrangement and connect to controller. Each harvester is connected with controller that makes a signal for voltage, temperature sensor, water leak sensor. In order to use electric energy by harvester, road markers are selected, which each harvester has three of road markers. A circuit for lighting the light emitting device using the output of the harvester installed in the rest area was designed and manufactured. Basically, a circuit is configured to light up the harvester output, and a commercial power supply can be used in case the output of the harvester is reduced due to the durability thereof, and a controller is manufactured for each harvester to connect the road markers. Key Words: Piezoelectric Harvester
        4.
        2018.05 구독 인증기관·개인회원 무료
        To be better fit for highways, pavement systems are required to provide comfortable and safe driving and be structurally durable. Composite pavements can be an effective option as they are more durable by placing a high functional asphalt overlay on a rigid concrete base layer. In order to apply a composite pavement system to the field, it is necessary not only to develop technologies that prevent reflecting crack and deterioration of the base layer, but also to improve bonding performance of materials and ensure structural performance as a pavement system against traffic loading. In advanced countries like Japan, USA and Europe, high-functional composite pavement systems are being put into practice across new highway networks. In this study, we evaluated structural performance (rutting, reflecting crack, and deflection) by applying traffic loads of actual highways through an accelerated pavement tester (APT) of a composite pavement section made up of a quiet porous surface laid over a water-proofing layer, a continuously reinforced concrete base, and a lean concrete sub-base layer, which was developed with new pavement methods used for each layer prior to field application. The APT specimen was constructed with paving materials and equipment actually used on site in the same dimensions (W3.5m*L14m*H2m) as actual highway sections in Korea, and 3-axle double-wheel heavy load (45ton) cart type KALES(Korean Accelerated Loading and Environmental Simulator) traveling on the specimen in both directions was used to simulate traffic loading. After applying around 8,574,000 ESALs of traffic loads, no reflecting crack occurred on the asphalt surface of the composite pavement, without surface distress except for rutting. In order to examine what causes rutting of pavements, we surveyed thickness of pavements by layer and measured asphalt density.
        5.
        2018.05 구독 인증기관·개인회원 무료
        Roller Compacted Concrete Pavement (RCCP) is placed by roller compaction of a mixture of less cement and unit water content and more aggregates and provides excellent early strength development with the help of interlocking of aggregates and hydration. The unit cement content of RCC pavements accounts for 85% of conventional pavements, with low drying shrinkage. As low drying shrinkage leads to smaller crack widths than ordinary concrete, RCC pavements can help elevate reflecting crack resistance if applied to a base layer of a composite pavement system. In a composite pavement with an asphalt surface laid over a concrete base, pavement temperature change is important in predicting pavement performance. As movement of the lower concrete layer is determined by temperature depending on pavement depth, temperature data of the pavement structure serves as an important parameter to prevent and control reflecting crack. Among the causes of reflecting crack, horizontal behavior of the lower concrete layer and curling-caused vertical behavior of joints/cracks are considered closely related to temperature change characteristics of the lower concrete course (Baek, 2010). Previous studies at home and abroad about reflecting crack have focused on pavement behavior depending on daily and yearly in-service temperature changes of a composite pavement (Manuel, 2005). Until now, however, studies have not been conducted on initial temperature characteristics of concrete in composite pavements where asphalt surface is placed over an RCC base. Annual temperature changes of in-service concrete pavements go up to 60 ℃, and those of asphalt overlays become around the twice at 110 ℃. This study evaluated initial crack behavior of composite pavement by investigating pavement temperature by depth of an RCC base and analyzing joint movement depending on change to temperatures of continuously jointed pavements. Findings from the study suggest that in composite pavements and asphalt overlays, time of laying asphalt has an important impact on crack behavior and reflecting crack.
        6.
        2018.05 구독 인증기관·개인회원 무료
        Roller Compacted Concrete Pavement (RCCP) is a pavement placed and compacted using an asphalt paver and a compaction roller by applying a small amount of concrete mixture and shows excellent structural performance as a result of hydration reaction of cement and interlocking of aggregates by roller compaction. It also provides economic advantages over conventional concrete pavements by reducing unit cement content and construction period, simplifying construction process, and decreasing traffic closure time (Wayne, 2006). However, given that it tends to show lower IRI levels than common concrete pavements since its low unit water content and binder weight ratios make uniform quality control difficult and roller compaction after paving makes the surface irregular and rough, with rough profile at the bottom of the pavement being reflected on the surface, RCCP is used mainly in port and industrial roads for low speed (60km/h or less) traffic (Dale Harringtion, 2010; Gregory, 2009). In order to apply RCCP to high-speed roadways, diamond grinding (DG) or asphalt overlay that is highly effective in improving roughness is needed (Fares Abdo, 2014; Gregory, 2009). Applying DG over RCCP leads to excellent skid resistance and noise reduction effects as a great percentage of aggregates makes the pavement surface rough, enhancing durability of concrete and the life of DG functionality. In addition, RCCP can be used as a high performance base layer of composite pavements, as it can reduce reflecting cracking at joints and cracked sections thanks to early strength development and low drying shrinkage of concrete. In this study, we assessed longitudinal roughness improvement effects by roughness-affecting factor by applying DG methods and asphalt overlays to three RCCP sites with a variety of sub-structural conditions and analyzed the effects on roughness of existing RCC pavements depending on surfacing method (DG, APOverlay).
        7.
        2018.05 구독 인증기관·개인회원 무료
        In recent years, pavement distresses have been caused by diverse factors such as spalling, deterioration of repaired sections, blow-up, and alkali aggregate reaction due to changing climate environment of a concrete pavement and its construction and maintenance conditions (supply of materials, increase in use of de-icers, etc,). As a leading repair method for deteriorated concrete pavements, partial-depth repair is implemented in accordance with guidelines of material properties for joints of a concrete pavement and field application evaluation systems, but still some of the repaired sections become deteriorated again at an early stage due to poor construction quality and failure of response to environmental impacts. Distresses that can be corrected with partial-depth repairs are largely divided into those of repair materials and of the existing pavement bonded to repair materials, and combined distress of repair materials and the existing pavement. Although re-repair methods should be different by distress type and scale than conventional pavement repair methods, appropriate repair methods and guidance for re-repairs have not been in place so far, and therefore currently, re-repair practices follow the existing manual of partial depth repairs. Therefore, this study evaluated concrete bond characteristics by removing method and repair scope for an experimental section of frequently distressed pavements to determine a re-repair scope and method for deteriorated partial depth repair sections of concrete pavement, the number of which has increased over time.
        8.
        2018.05 구독 인증기관·개인회원 무료
        Composite pavements are constructed by placing a high functional asphalt surface layer on a high performance concrete rigid base layer and provide a more durable, high functional surface to road users. Service life of composite pavements is dependent on the bonding performance of the lower rigid base and the flexible surface layer. Accordingly, it is necessary to place an impermeability layer between the functional surface layer and the rigid base to enhance bonding performance and to prevent moisture penetration into the rigid base and deterioration of pavement. In order to use optimal composite pavement sections, two types were applied to impermeability layer: highly impermeable water-tight SMA and mastic asphalt currently in use. APT (Accelerated Pavement Testing) and experimental construction were carried out to evaluate bond strengths between the rigid base and the impermeability layer depending on the type of impermeability layers. Composite pavement sections for the APT had a 22 cm concrete rigid base layer and a 5cm functional surface, as well as either 5cm of SMA impermeability layer and 5cm of mastic layer. After applying around 8,574,000 ESALs, pull-off test was conducted, which showed that the mastic section outperformed the SMA section. In the experimental construction, three types of rigid base layers, JCP (Jointed Concrete Pavement), CRCP (Continuously Reinforced Concrete Pavement), and RCCP (Roller Compacted Concrete Pavement), were used for composite pavement sections, and as in the APT, two types of impermeability layers, SMA and mastic, were used per rigid base layer of new and deteriorated concrete pavement. Therefore, seven composite pavement sections in total were constructed. We measured the bond strength over one year or so following the construction of these composite pavement sections and found that regardless of the type of rigid base layer and whether it was new or not, those sections with a mastic impermeability layer had high bond strengths.
        9.
        2018.05 구독 인증기관·개인회원 무료
        In Korea, concrete pavements were first applied to highways in 1981 and as a result of continued increase in length over the past years, 2,592 km of concrete pavement network is currently in service, of which 1,399 km(54%) of concrete pavements is 10 years or older, and 233km(9%) is 20 years or older. The length of concrete pavement sections nationwide has been steadily on the rise every year (EXTRI, 2017). Approximately 54% of current concrete pavement highway network will reach the service life limit in 2025 which means around 660 billion won is needed for future pavement repair project (EXTRI, 2017). Given that concrete pavements beyond design life still have a remaining service life, it is economically advantageous to repair them before reconstruction. Asphalt overlays are a major repair method for older concrete pavements. Depending on the concrete pavement condition, thickness and mixture of asphalt overlays are determined. Service life of asphalt overlays varies by the presence, time and size of cracks in existing concrete pavements and reflecting crack at joints. Temperature change of concrete pavement is among the major reaction parameters of reflecting crack. Reflecting crack develops when asphalt bottom-up cracking by longitudinal shrinkage and expansion due to temperature change of the concrete base layer, top-down cracking by temperature difference between top and bottom of concrete, and shear stress by traffic loading are combined (Baek, 2010). Crack and joint behaviors of concrete pavement vary between the base layer and the concrete surface of composite pavement system, and different conductivity by mixture and thickness of asphalt overlay leads to temperature change of concrete base course. This study measured temperatures of each layer of diverse composite pavements in place on site and analyzed differences in temperature change of concrete base layer depending on mixture and thickness of asphalt overlays. Overlay thickness parameters were 5cm and 10cm, two values most widely used, while mixture parameters were SMA and porous asphalt. Based on temperature change of concrete surface, this study also evaluated the difference of temperature change in concrete base layer with an asphalt overlay on top. Findings from this study are expected to be utilized for studies on mechanism and modeling of reflecting crack in old concrete pavements with asphalt overlays.
        10.
        2018.05 구독 인증기관·개인회원 무료
        Roller-compacted concrete (RCC) has been widely used for construction of pavements [1]. The strength of RCCP can be obtained from not only hydration of binder but also the aggregate interlock resulted from roller-compaction [2]. For this reason, RCCP normally achieves higher strength compared to conventional concrete pavement with similar cement content. Even though RCCP can be provided a good structural performance, it has been difficult to verify the long-term performance though actual field construction. Therefore, this study aimed to investigate the fatigue characteristics and crack development in RCCP based on full-scale fatigue test and accelerated pavement test. In case of full-scale fatigue tests, fatigue behavior was evaluated by using 1 m × 1 m dimensional RCC slab specimens obtained from the field in order to consider the field variability. Fatigue equation derived from this study shows that the number of load repetitions which causes fatigue failure at the same stress level is slightly larger than that of PCA fatigue equation. In order to evaluate the performance of RCCP, two phases of accelerated pavement test (APT) were conducted. In phase one, the performance of RCCP at two different strengths (35.6 and 30.4 MPa) was evaluated. In phase two, the performance of RCCP with different thickness (5, 7.5 and 10 cm) was investigated. The number of load repetition of fatigue crack occurrence in each section was compared to the estimated fatigue failure determined from fatigue equation of RCCP. The crack development in each section was compared to the AASHTO crack model for JPCP. Overall, it was confirmed that RCCP has equal or better performance compared to JPCP the estimation in term of fatigue cracking. The fatigue equation from PCA and cracking model from AAHTO can be used on RCCP at certain design thickness range.
        11.
        2016.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Malodor emitted while producing fertilizer from hatchery egg waste treated with microorganism is an important limiting factor. To reduce this problem, we attempted to use two yeast strains, Saccharomyces cerevisiae, KACC 30008 and KACC 30068. Both yeast strains reduce ammonia gas emission 35.4% than only treated with bacterium, Bacillus amyloliquefaciens. When both strains were used together, that was reduced as 57.1%. KACC 30008 and 30068 strains reduced hydrogen sulfide 42 and 90.4%, respectively. Both strains together reduced hydrogen sulfide gas as 98.5%. KACC 30008 did not decrease methyl mercaptan emission. However KACC 30068 decreased 40% and both strains together decreased the gas emission as 66.7%. Overall, this study showed that yeast treatment could enhance the effect of B. amyloliquefaciens treatment in the reduction of malodorous gas emission.
        4,000원
        15.
        2015.03 KCI 등재 서비스 종료(열람 제한)
        This study investigated possible involvement of photoperiodic regulation in reproductive endocrine system of female olive flounder. To investigate the influence on brain-pituitary axis in endocrine system by regulating photoperiod, compared expression level of Kisspeptin and sbGnRH mRNA in brain and FSH-β, LH-β and GH mRNA in pituitary before and after spawning. Photoperiod was treated natural photoperiod and long photoperiod (15L:9D) conditions from Aug. 2013 to Jun. 2014. Continuous long photoperiod treatment from Aug. (post-spawning phase) was inhibited gonadal development of female olive flounder. In natural photoperiod group, the Kiss2 expression level a significant declined in Mar. (spawning period). And also, FSH-β, LH-β and GH mRNA expression levels were increasing at this period. However, in long photoperiod group, hypothalamic Kiss2, FSH-β, LH-β and GH mRNA expression levels did not show any significant fluctuation. These results suggest that expression of hypothalamic Kiss2, GtH and GH in the pituitary would change in response to photoperiod and their possible involvement of photoperiodic regulation in reproductive endocrine system of the BPG axis.
        16.
        2014.09 KCI 등재 서비스 종료(열람 제한)
        Sorghum seed is traditionally used as secondary food sources in addition to rice in Korea. While the hypoglycemia regulating phytochemicals have been found in sorghum seed, peptides related with hypoglycemia never been studied before. To obtain the peptide characteristics and the specifically high-expressed peptides in hypoglycemic sorghum seed, peptide profiles of seven hypoglycemic and five nonhypoglycemic sorghum lines bred in RDA were determined using surface-enhanced laser desorption/ionization time-offlight mass spectrometry (SELDI-TOF MS). The twelve sorghum lines exhibited 104 peptides on CM10 protein chip array (weak cation exchange) and 95 peptides on Q10 (weak cation exchange) in the molecular mass range from 2,000 to 20,000 Da. Heat map via supervised hierarchical clustering of the significantly different peptides (p < 0.01) in peak intensity among the 12 lines effectively revealed the specifically upregulated peptides in each line and distinguished between 7 hypoglycemic and 5 non-hypoglycemic lines. Through the comparison with hypoglycemic and non-hypoglycemic lines, 10 peptides including 2231.6, 2845.4, 2907.9, 3063.5, 3132.6, 3520.8, 4078.8, 5066.2, 5296.5, 5375.5 Da were specifically high-expressed in hypoglycemic lines at p < 0.00001. This study characterized seed peptides of 12 sorghums and found ten peptides highly expressed for hypoglycemic sorghum lines, which could be used as peptide biomarkers for identification of hypoglycemic sorghum.
        17.
        2014.09 KCI 등재 서비스 종료(열람 제한)
        Sorghum seed is traditionally used as health supplements and the secondary food mixed with rice in Korea. While the research of reserve protein in sorghum seed have been carried out in many countries used as major food, much less is known about reserve proteins of Korean local sorghum seeds. To obtain protein characteristics in 20 Korean local sorghum seed, quantitative content of reserve protein was determined after fractionation by modified ‘Osbone’ method and α-kafirin of prolamin was determined by SDSPAGE. Mean albumin, globulin, prolamin and glutelin contents based on total seed protein content of 20 Korean local sorghum seed were 6.2%, 0.9%, 57.9% and 35.1%, respectively. Sorghum cultivar with high prolamin were ‘Whin-susu’, ‘Whin-Chalsusu’, ‘Whanggeum-Chalsusu’, and ‘Daepungshushu’. Sorghum cultivar with high α-kafirin were ‘Whin-susu’, ‘Geumsan-Chalsusu’, ‘Whin-Chalsusu’, and ‘Jangmok-susu’. Among the 20 varieties, ‘Whin-susu’ and ‘Whin-Chalsusu’ were selected as high α -kafirin and prolamin sorghum cultivar, which showed 64.5 and 71.9% of prolamin contents, respectively.
        18.
        2012.07 서비스 종료(열람 제한)
        Cereal seeds, sorghum, foxtail millet, hog millet, adlay, and corn are traditionally used as health assistant as well as energy supplying food in Korea. While beneficial phytochemicals to human have revealed in cereals, the information on peptides from cereals is far less accumulated than major reserve protein. Here, we analyzed peptide profiles using surface enhanced laser desorption/ionization time of flight mass spectrometry (SELDI-TOF MS) in cereal seeds for construction of peptide information and attempted to develop peptide biomarkers for cereal identification. To optimize the analysis condition of SELDI-TOF MS, the effect of dilution factor on binding affinity to protein chips was tested using CM10 and Q10 arrays. Peptide clusters were significantly different at the level of 0.01 p-value. Peak spectra were the most stable in 1:50 of dilution factor in both chip arrays. Numbers of detected peak of 5 cereal seeds were 131 in CM10 and 74 in Q10 array. Each cereal was grouped as a cluster and well discriminated into different cluster in the level of 0.01 p-value. Numbers of potentially identified peptide biomarkers are 11, 13, 9, 5 and 12 in sorghum, foxtail millet, hog millet, adlay and corn, respectively. This study demonstrates that each cereal seed have own distinguishable specific peptides although their function are not identified yet in this study. In addition, the proteomic profiling using SELDI-TOF MS techniques could be a useful and powerful tool to discover peptide biomarker for discrimination and assess crop species, especially under 20 kDa.