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        검색결과 165

        41.
        2017.10 구독 인증기관·개인회원 무료
        The hawthorn spider mite, Amphitetranychus viennensis (Zacher), is an important tetranychid causing damage on fruittrees and woody ornamental plants. We investigated the effect of a mycoinsecticide BotaniGard® ES at different humiditylevels on the eggs and adults mortality of A. viennensis. In a laboratory condition, egg mortality was significantly influencedby the conidial concentration and RHs. Highest mortality of eggs was observed at 1×108 conidia/ml with 95% RH thanother conditions. In 1×108 conidia/ml, LT50 at 95 and 75% RH were significantly different from 55% RH. In BotaniGard®spray in cherry plants, mites decreased on day 6 at all the concentrations, but the mite populations rebounded exceptin 1×109 conidia/ml where it maintained 0 until 9 days after spraying. It is therefore concluded that B. bassiana hasa potential to be used against A. viennensis
        42.
        2017.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In order to reduce odor and methane emission from the landfill, open biocovers and a closed biofilter were applied to the landfill site. Three biocovers and the biofilter are suitable for relatively small-sized landfills with facilities that cannot resource methane into recovery due to small volumes of methane emission. Biocover-1 consists only of the soil of the landfill site while biocover-2 is mixed with the earthworm casts and artificial soil (perlite). The biofilter formed a bio-layer by adding mixed food waste compost as packing material of biocover-2. The removal efficiency decreased over time on biocover-1. However, biocover-2 and the biofilter showed stable odor removal efficiency. The rates of methane removal efficiency were in order of biofilter (94.9%)>, biocover-1(42.3%)>, and biocover-2 (37.0%). The methane removal efficiency over time in biocover-1 was gradually decreased. However, drastic efficiency decline was observed in biocover-2 due to the hardening process. As a result of overturning the surface soil where the hardening process was observed, methane removal efficiency increased again. The biofilter showed stable methane removal efficiency without degradation. The estimate methane oxidation rate in biocover- 1 was an average of 10.4%. Biocover-2 showed an efficiency of 46.3% after 25 days of forming biocover. However, due to hardening process efficiency dropped to 4.6%. After overturn of the surface soil, the rate subsequently increased to 17.9%, with an evaluated average of 12.5%.
        4,200원
        43.
        2017.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES:The objective of this study is to ascertain the curing period of cementless cold central plant recycled asphalt base-layer, using mechanical analyses and specimen quality tests on the field.METHODS :Cold central plant recycled asphalt base-layer mixture was produced in the plant from reclaimed asphalt, natural aggregate, filler for the cold mix, and the modified emulsion AP using asphalt mix design and plant mix design. In order to examine the applicability of the curing period during the field test, the international standards for the possibility of core extraction and the degree of compaction and LFWD deflection were analyzed. Moreover, Marshall stability test, porosity test, and indirect tensile strength test were performed on the specimens of asphalt mix and plant mix design.RESULTS :The plant production process and compaction method of cementless cold central plant recycled asphalt base-layer were established, and the applicability of the optical moisture content for producing the mixture was verified through the field test. In addition, it was determined that the core extraction method of the conventional international curing standard was insufficient to ensure performance, and the LFWD test demonstrated that the deflection converges after a two-day curing. However, the back-calculation analysis reveals that a three-day curing is satisfactory, resulting in a general level of performance of dense asphalt base-layer. Moreover, from the result of the specimen quality test of the asphalt mix design and plant mix design according to the curing period, it was determined that the qualities satisfied both domestic and international standards, after a two-day curing. However, it was determined that the strength and stiffness after three-day curing are higher than those after a two-day curing by approximately 3.5 % and 20 %, respectively.CONCLUSIONS:A three-day curing period is proposed for the cementless cold central plant recycled asphalt base-layer; this curing period can be demonstrated to retain the modulus of asphalt-base layer in the field and ensure stable quality characteristics.
        4,000원
        44.
        2016.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Naval combat system developed in-country is progressing at an alarming rate since 2000. ROK navy will be achieved all vessels that have combat system in the near future. The importance of System Engineering and Integrated Logistics Support based on reliability analysis is increasing. However, reliability analysis that everyone trusted and recognized is not enough and applied practically for development of Defense Acquisition Program. In particular, Existing Reliability Analysis is focusing on reliability index (Mean Time Between Failure (MTBF) etc.) for policy decision of defense improvement project. Most of the weapon system acquisition process applying in the exponential distribution simply persist unreality due to memoryless property. Critical failures are more important than simple faults to ship’s operator. There are no confirmed cases of reliability analysis involved with critical failure that naval ship scheduler and operator concerned sensitively.Therefore, this study is focusing on Mean Time To Critical Failure (MTTCF), reliability on specific time and Operational Readiness Float (ORF) requirements related to critical failure of Patrol Killer Guided missile (PKG) combat system that is beginning of naval combat system developed in-country. Methods of analysis is applied parametric and non-parametric statistical techniques. It is compared to the estimates and proposed applications. The result of study shows that parametric and non-parametric estimators should be applied differently depending on purpose of utilization based on test of normality. For the first time, this study is offering Reliability of ROK Naval combat system to stakeholders involved with defense improvement project. Decision makers of defense improvement project have to active support and effort in this area for improvement of System Engineering.
        4,200원
        45.
        2016.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was carried out to determine the effects of application levels of fertilizer and sowing methods on yields and nutritive values of Italian ryegrass (IRG) in early spring. Five fertilizer levels were used: Treatment 1, 100-80-80 kg/ha; Treatment 2, 120-100-100 kg/ha; Treatment 3, 140-120-120 kg/ha; Treatment 4, 160-140-140 kg/ha; Treatment 5, 140-120-120 kg/ha of N-P2O5-K2O with silicate fertilizer 200 kg/ha. Dry matter (DM) yield was 8,330 kg/ha in Treatment 5, 7,686 kg/ha in Treatment 4, and 7,347 kg/ha in Treatment 3. There was no significant difference in total digestible nutrients (TDN) content. The content of crude protein was the highest in Treatment 5. Dry matter ratio was the lowest in Treatment 5. In Treatment 3, DM yield was 7,347 kg/ha, when total amounts of fertilizers were applied at one time. However, DM yield was 7,405 kg/ha, when 50% of pre-planting fertilizer and 50% of supplementary fertilizer were applied at different time. There was no significant difference between total application and split application of fertilizers. However, DM yield was 9,469 kg/ha in application treatment with 100 kg/ha of additional urea at three to four leaf stages of IRG. Regarding DM yield by sowing methods of IRG, the following order was found: drill seeding (8,176 kg/ha) > rotary-broadcast seeding-stamping (7,957 kg/ha) > rotary-broadcast seeding (7,810 kg/ha) > broadcast seeding (7,347 kg/ha) > broadcast seeding-rotary (7,034 kg/ha). DM yield (59.57%) was the lowest in broadcast seedingrotary. Crude protein content was the highest with rotary work but the lowest with broadcast seeding.
        4,000원
        46.
        2016.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Wire rods having various sectional shape are generally used in various applications. In a 2-roll shape rolling process, step-by-step rolling operations are executed repeatedly and the rollers must be changed whenever the sectional shape of wire rod is changed. The frequent changes of the rollers and discontinuous repeated operations are cause various shortcomings such as increase of manufacturing cost and reduction in precision. We had developed a high precision automatic wire rod manufacturing system to reduce these shortcomings in the previous study. In this study, we evaluated the field application performance of the developed system in terms of straightness, thickness deviation, surface precision, tensile and hardness of the wire rod in order to verify the feasibility of the system.
        4,000원
        47.
        2016.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES: This study evaluated the field applicability and laboratory performance of glass fiber-reinforced asphalt (GFRA) mixtures. METHODS : The general hot-mix asphalt (HMA) and GFRA mixtures were paved in five sites, including three national highways, one express highway, and an arterial road, to evaluate field applicability and durability. The plant mixing and construction method for the GFRA were similar to those for the general HMA. The lab performances of the field samples were relatively compared through the mechanical measures from the Marshall stability, indirect tensile strength, and dynamic stability. The field performance was surveyed after a year. RESULTS : The lab tests verified the superior lab performances of the GFRA compared to the general HMA. The Marshall stability of the GFRA increased for about 128% of the general HMA. The indirect tensile strength of the GFRA was 115% greater than that of the general HMA. The dynamic stability of the GFRA resulted in 16,180 reps/mm, which indicated that high rut resistance may be expected. No noticeable defects, such as cracks or deformation, were observed for the GFRA sections after a year. CONCLUSIONS: The lab tests and field survey for the five GFRA sites resulted in superior performances compared to the general HMA. The relatively low-cost GFRA, which required no pre-processing procedures, such as polymer modification, may be a promising alternative to the polymer-modified asphalt mixtures. The long-term performance will be verified by the superior field durability of the GFRA in the near future.
        4,000원
        48.
        2016.04 구독 인증기관·개인회원 무료
        This study was performed to apply and to utilize the digital forecasting information for Integrated Pest Management at pepper field in Chungbuk province. Chemical spray according to the forecasting prediction using FarmIPM and NCPMS were compare to the that of no control and conventional control. Pests such as Oriental tobacco budworm, Western flower thrips, and Cotton aphids were investigated the control effect by the forecasting modeling information at three pepper plots. Damaged fruit ratio (%) of Oriental tobacco budworm was ordered into no treatment (30) > forecasting (20) > conventional (12), but damages by other pest was insignificant. The frequency of forecasting control was ordered into NCPMS (31) > conventional control (17) > FarmIPM (8). Damaged fruit ratio (%) of Oriental tobacco budworm was ordered into no treatment (35.5) > NCPMS (26.1) > FarmIPM (24.6) > conventional (13.9). Density of western flower thrips was higher but had no problematic by the chemical control when it is hard to analyze the damage by cotton aphid occurrence. Damage by cotton aphids has no prediction of forecasting but done with 6th chemical spray, and their damage ratio (%) was ordered into no treatment (67.7) > FarmIPM (16.2) > NCPMS (11.3) > conventional treatment (4.8). At an analysis of economic value, gross profit was highest in FarmIPM and next to NCPMS > conventional control.
        49.
        2016.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES : The field application and performance of continuously reinforced concrete pavement (CRCP), constructed by using the mechanical tube-feeding method, are evaluated in this study. METHODS: The location of the rebar was evaluated by using the MIRA system. The early-age CRCP performance was evaluated via visual survey, in which the crack spacing and crack width were examined. RESULTS: The location of longitudinal reinforcing bars was evaluated via MIRA testing and the results showed that the longitudinal rebars all lie within a given tolerance limit (±2.5 cm) of the target elevation. In addition, owing to the low temperature when the concrete was pured, the crack spacing in the Dae-Gu direction is slightly wider than that of the Gwang-Ju direction. Almost all of the crack spacings lay within the range of 1.0 m~3.0 m. A crack width of <0.3 mm was measured at the pavement surface. However, as revealed by the field survey, the crack spacing was not correlated with the crack width. CONCLUSIONS : In CRCP constructed by using the mechanical tube-feeding method, almost all of the longitudinal reinforcing bars lay within the tolerance limit (2.5 cm) of the target elevation. The concrete-placing temperature affects the crack spacing, owing to variations in the zero-stress temperature. Crack survey results show that there is no correlation between the crack spacing and crack width in CRCP.
        4,000원
        50.
        2015.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 실험은 논 토양에서 사일리지용 수수 × 수수 교잡종 재배시 화학비료와 발효 돈분 액비 혼용 시용이 생육특성 및 영양성분에 미치는 영향을 조사하고자 실시하였다. 실 험설계는 화학비료 100% 처리구 (C), 화학비료 70% + 돈분 액비 30% 처리구 (T1), 화학비료 50% + 돈분액비 50% 처 리구 (T2), 화학비료 30% + 돈분액비 70% 처리구 (T3) 그리 고 돈분액비 100% 처리구 (T4)로 한, 5처리 3반복 난괴법 으로 배치하였다. 이때 돈분 액비 시용은 질소량만을 기준 으로 하였다 (150 kg/ha). 초장, 엽장, 엽폭 그리고 경의 굵 기는 T4구가 유의적으로 작게 나타났다 (p<0.05). 경의 경 도는 돈분액비 시용 비율 낮고 화학비료 시용 비율이 높을 수록 유의적으로 증가하였다 (p<0.05). 생초수량은 T2구가 높았던 반면 T3구가 낮게 나타났다 (p<0.05). 그러나 건물 수량 및 TDN 수량은 처리구들 간에 유의적인 차이를 보이 지 않았다. 조단백질 함량은 T1구가 다른 구에 비하여 높 게 나타났다 (p<0.05). 조지방 함량은 T1, T2, T3 그리고 T4 처리구들 간에는 유의적인 차이가 없었지만, C구와는 유의적인 차이를 보였다 (p<0.05). NDF와 조섬유 함량은 각각 T3구와 C구에서 높게 나타났다 (p<0.05). 그러나 ADF 함량은 처리구들 사이에 유의적인 차이를 보이지 않았다. 총무기물 함량은 T1 > T2 > T4 > T3 > C 구 순으로 높게 나 타났다 (p<0.05). 유리당 함량은 T1과 C구가 다른 처리구에 비하여 유의적으로 높게 나타났다 (p<0.05). 이상의 결과를 종합해 볼 때, 돈분액비 시용은 화학비료에 비하여 수량성, 영양성분에 크게 떨어지지 않기 때문에 사일지용 수수 × 수수 교잡종 재배시 돈분액비와 화학비료를 혼용 시용 하 거나 돈분액비 만 시용하여도 큰 무리가 없는 것으로 판단된다.
        4,000원
        51.
        2015.07 구독 인증기관 무료, 개인회원 유료
        현대사회에서 범죄문제는 개인 간의 물리적인 피해와 함께 경제적, 사회적 피해를 발생시키며 지역사 회의 신뢰관계를 무너뜨리는 가장 시급히 해결되어야 할 사회문제라고 할 수 있다. 교정복지란 범죄로 인 해 발생한 부정적인 영향력을 해결하고 범죄 당사자들의 원만한 사회복귀를 위해 노력하는 일련의 과정 이라고 할 수 있다. 본 연구는 우리나라 범죄 현황과 교정현장을 파악함으로써 교정복지의 필요성과 교정 복지 분야를 이해하고, 기존의 사회복지실천 모델들의 교정복지 현장 적용을 위해 제안을 시도하고자 한다. 교정현장의 사회복지실천 적용을 위해서는 첫째, 교정현장에 대한 관심과 이해가 선행되어야 한다. 둘째, 다양한 교정대상자 및 교정현장에 적합한 사회복지실천 모델들이 개발되고 실험되어야 한다. 셋째, 교정사회복지사 양성을 위한 실천가 양성 프로그램이 마련되어야 한다. 넷째, 교정현장의 민간자원 연계가 원활히 이루어지도록 교정현장이 개방되어야 한다. 다섯째, 교정대상자의 사회복귀를 위한 정책적 지원이 확대되어야 한다.
        4,800원
        52.
        2014.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        자동취수 물꼬와 토사유출저감 물꼬의 현장 적용성을 평가하기 위하여 2012년부터 2013년까지 2년 동안 취수량, 배출수량, 수질농도변화 그리고 생육 및 생산성을 조사하여 얻은 결과는 다음과 같다. 1. 관행 물꼬 관리 논과 자동취수 물꼬관리 논의 취수량은 각각 1,634 mm/yr와 922 mm/yr로 관측되었으며, 43.6%의 절약효과가 산정되어 용수량 절약에 효과적인 것으로 나타났다. 2. 자동취수 물꼬를 설치한 논의 배출수량이 관행 물꼬 관리 논에 비하여 38.6% 감소하였다. 3. 토사유출저감 물꼬를 설치한 논에서 SS는 22.8 ~ 75.0%, COD는 9.7 ~ 45.5%, TN은 0 ~ 64.5%, TP는 0 ~ 42.5%의 농도 개선효과가 있는 것으로 나타났다. 4. 개선된 물꼬 관리 논과 관행 물꼬 관리 논의 벼 생육과 생산량은 큰 차이가 없는 것으로 조사되었다. 이러한 연구결과로 볼 때 자동취수 물꼬와 토사유출저감 물꼬를 이용한 논의 물꼬 관리 시스템 개선은 생산량을 유지하며 수자원 및 물 환경을 보전하기 위한 좋은 시설로 판단된다.
        4,000원
        53.
        2014.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 가축분뇨를 화학비료로 대체하기 위해 사료용 옥수수 재배시 돈분 액비의 적정 시용방법을 구명하고자 화학비료100%, 액비100%, 액비150%, 액비50% +화학비료50%, 액비70% +화학비료30%, 액비70% +화학비료50%를 처리한 후 작물의 수량 및 사료가치, 토양변화 등을 조사하였다. 토양의 화학성 변화중 pH와 치환성 Mg는 시험전에 비하여 큰 변화가 없었으나 그 밖의 성분들은 화학비료구를 제외한 액비처리구의 경우 약간씩 높은 함량을 나타내었다. 토양중 NO3-N함량과 옥수수 생육초기에는 화학비료100%, 액비150%, 액비70% +화학비료50%처리구가 그 밖의 액비와 화학비료 분시구보다 높았으나 생육후기로 갈수록 처리간에 큰 차이가 없었다. 사료용 옥수수의 전장, 직경 및 생체수량은 화학비료100%, 액비150%, 액비70% +화학비료50%처리구에서 가장 양호하였고 액비100% 전량기비처리구에서 가장 낮았다. 특히, 수량은 액비150%처리구와 액비70%+화학비료50%에서 유사하였으며, 액비100%에서 79%로 가장 저조하였다. 사료용 옥수수의 조단백질과 사료가치도 역시 액비150%, 액비70%+화학비료50%에서 가장 높은 값를 나타냈지만, ADF와 NDF 함량은 가장 낮은 값을 나타내었다. 이상의 결과를 종합해 보면 논 조건에서 화학비료를 대체하여 가축분뇨 액비를 이용한 옥수수 재배시 증수와 사료가치를 높이기 위해서는 일시에 100%전량을 사용하는 것보다는 2회 분할 시용하는 것이 유리하며 특히, 액비70%를 처리하고 추비로 화학비료50%를 처리하는 것이 토양비옥도를 유지하면서도 생산성을 높여 주며 화학비료를 50%수준 절감해줄 것으로 생각된다.
        4,000원
        54.
        2014.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was conducted to investigate the influence of the mixed application of chemical fertilizer (CF) and liquid swine manure (LSM) on the agronomic characteristics, dry matter yield, amino acids, minerals, and free sugars in cultivating Sorghum × Sudangrass hybrid (SSH) on paddy soil. The field experiment was designed in a randomized block design with three replications and consisted of CF 100% (C), CF 70% + LSM 30% (T1), CF 50% + LSM 50% (T2), CF 30% + LSM 70% (T3), and LSM 100% treatment (T4). The application of LSM was based solely on the nitrogen. Plant length, leaf length, leaf width and number of leaf were significantly higher in T4 (p<0.05), but stem diameter did not show significant differences among treatments. Stem hardness increased significantly (p<0.05) as the LSM application rate decreased, but sugar degree decreased significantly (p<0.05) as the LSM application rate decreased. Fresh yield, dry matter yield and TDN yield were the highest in T4, whereas the lowest in T2 (p<0.05). Crude protein, crude fat and crude ash were the highest in C, T4 and T2, respectively (p<0.05). However, NDF and ADF did not show significant difference among treatments. Crude fiber decreased significantly (p<0.05) as the LSM application rate increased. The total mineral content was decreased significantly (p<0.05) as the LSM application rate increased. Total amino acid content was higher in the order of T1> C> T3> T4> T2 (p<0.05). Free sugar content increased significantly (p<0.05) as the LSM application rate increased. The analysis of all the above results suggests that the application of liquid swine manure is very effective, considering the yield performance and the content of sugar degree and free sugar. In addition, liquid swine manure may be possible to grow Sorghum × Sudangrass hybrid without chemical fertilizer.
        4,000원
        55.
        2014.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 전라북도 부안군 채석강 지역에 대한 3D파노라마 가상 현실 지질 답사 투어 학습자료를 개발하였다. 개발된 프로그램은 360˚×180˚ 파노라마로서 관측 지점의 모든 면을 볼 수 있고, 확대, 축소, 화면 돌리기 등의 상호작용이 가능하다. 이 프로그램의 교육적 효과를 얻기 위해 컴파스 활용하기, 지층의 경사 등을 측정하기 위한 이동 가능한 각도기 제공, 관찰 지점의 표본에 대한 3D 관찰하기 등을 제공하였다. 또 주요 관찰 포인트에는 확대된 사진, 팝업창, 전문가 설명 등으로 학습을 도왔다. 이 프로그램의 교육적 효과를 알아보기 위하여 중학교 과학 영재반 학생 35명에게 적용해본 결과 약 85% 이상의 긍정적인 반응을 보여주었다. 따라서 이 프로그램은 중학교 과학과 지질학 수업 시 간접적 상황학습이 될 수 있고, 시간문제, 비용문제, 안전문제 등을 줄일 수 있는 하나의 보충적인 지질 답사 방법이 될 것이다.
        4,300원
        56.
        2014.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Indoor air quality including metro subway is of recent interests in large cities. Inflow air to the inside of the train and circulating air flow through MVAC of stations contain large amount of iron based fine particles. This paper evaluated the collection of such a dust by magnetic filters as comparing to conventional particle capturing mechanisms such as inertia, direct impaction and diffusion. It was found that filtration velocity, magnetic field intensity, and fiber size were the most important parameters for magnetic filtration. Application of magnetic force obviously enhances the collection efficiency particularly in fine modes smaller than 10 mm. However, its effect was found greater in 2.5 mm than submicron particles.
        4,000원
        57.
        2013.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES: This research investigates traffic noise characteristics as change the transverse rumble strips shape from rectangular to cylinder at toll plaza of highway. METHODS : The traffic noise was investigated at two different places at toll plaza of highway. One is modified grooving, another is employed cylinder shape of TRS instead of rectangular shape of TRS. A measurement of traffic noise was conducted at same location and time period. The traffic volume information was gotten from office of highway office and vehicle speed was measured by speed measuring device. The traffic noise measurement was conducted from 13:00 to 23:00 and by pass-by method. Also, the traffic noise was measured behind noise barrier. Various distance from noise barrier(7.5m, 30m, 50m) and different heights(1.2m, 3m, and 5m) were parameter for measurement of traffic noise in this study. RESULTS : The class 1 vehicle was contributed from traffic volume which was increased 1,500. However, the distribution of traffic speed didn’t change compare to previous investigated period. From this study, It was found that the external traffic noise was changed as function of geometric shape of TRS. The external noise from modified grooving was less than 1.2dB(A) of the current TRS. A difference of traffic noise was 20dB(A) before and after barrier. It came from a noise barrier effect as reduction of traffic noise. According to investigate a traffic noise distribution near barrier, there is similar noise characteristic as function of height at 7.5m distance from noise barrier. Also, There is no different traffic noise between 30m and 50m from source of the noise of sound barrier. CONCLUSIONS: Based on this traffic noise investigation result, there is a clear characteristic difference as changed TRS shape. The traffic noise was reduced by changed TRS shape. Specially, traffic noise was decreased although the traffic volume was increase for same investigation time and period. It is implied that cylinder type of TRS significantly reduces the traffic noise. The specification of various TRS will be studied in the future.
        4,000원
        58.
        2013.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES : The purpose of this study is to evaluate of field application and laboratory performance of warm-mix asphalt (WMA) according to the dosage rate of organic-based WMA additive. METHODS: Three asphalt mixtures, i.e., hot mix asphalt (HMA), WMA with the dosage rate of 1.5%, WMA with the dosage rate of 1.0%, were sampled from the asphalt plant when the field trial project were constructed. With these mixtures, the laboratory testings were performed to evaluate the linear viscoelastic characteristics and the resistance to moisture, rutting and fatigue damage. RESULTS : From the laboratory test results, it was found that the WMA with the reduced dosage rate of additive would be comparable to HMA and WMA with the original dosage rate in terms of the dynamic modulus, tensile strength ratio, rutting resistance. However, the fatigue reisistance of WMA with the reduced dosage rate was slightly worse but it should be noted that the fatigue performance is necessarily predicted by combining the material properties and pavement structure. CONCLUSIONS: Through the field construction and laboratory testings, the dosage rate of organic-based WMA additive could be reduced from 1.5% to 1.0% without the significant decrease of compactability and laboratory performance. The long-term performance of the constructed pavement will be periodically monitored to support the findings from this study.
        4,000원
        59.
        2013.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        이 연구는 강원도 고성군 지역에 분포하는 뒤배재 화산체와 서낭바위를 대상으로 화성암 지역의 지형과 지질학습을 위한 야외지질학습장을 개발하는 것이다. 그리고 고등학교 1학년을 대상으로 그 교육적 효과를 알아보았다. 연구절차는 Orion의 모형에 근거하여 준비 단계, 야외학습 단계 및 정리 단계 순이며, 교육과정에 제시된 지질학습 요소를 바탕으로 야외지질학습장을 개발하였다. 야외학습 전에 학생들은 광물, 암석 등에 대하여 단순히 암기하고 있으며, 화강암과 현무암이 분포하는 지형의 형성과정에 대한 이해도는 매우 낮았다. 특히, 화강암과 현무암이 한 마그마에서 동시에 형성되는 것으로 이해하고 있다. 야외학습 후, 학생들은 광물, 암석 및 지질구조 등에 대한 단순한 지식은 학습이 잘 되었으나, 화강암과 현무암의 생성시기를 인식하지 못하여, 두 암석의 지형적 특성을 제대로 설명하지 못하였다. 이유는 중학교에서 화강암과 현무암의 생성과정에 대한 단순한 개념은 학습하였으나, 두 암석이 생성되는 지질시대 차이에 대한 의미는 학습하지 않았기 때문인 것으로 해석된다.
        4,300원
        60.
        2013.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        도장공정에서 발생되는 휘발성 유기화합물의 회수를 위하여 중공사 분리막 모듈을 이용한 공정을 준비하여, 공급 압력과 시간변화에 따른 휘발성 유기화합물의 회수에 대한 특성평가를 실시하였다. 중공사 분리막 모듈을 도장공정에 직접 적용한 결과, 투과된 휘발성 유기화합물의 농도는 투과시간과 압력의 증가됨에 따라 증가되었으며, 단일공정보다 다단공정이 더 우수한 분리성능을 나타내는 것을 확인하였다.
        4,000원
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