By analyzing the compressive strength througth field test execution on the shotcrete mixture with 40% blast furnace slag and slurry accelerator, confirmed the suitability as subsea tunnel material. As a result, strength characteristic on the anti-chloride shotcrete is excellent evaluated in terms of compressive strength compared with existing shotcrete.
Traditional marine structures are difficult to construct under the marine environment. These structure have maintenance costs associated with the chloride attack environments. In this paper, a new structure system is proposed to overcome these disadvantages. The connection of precast reinforced concrete girders and bent cap is the main feature of the proposed structure system. To assess the joint performance of the proposed methods, full-scale joint was fabricated and tested under cyclic loading. The key parameters examined were the pile displacement; the strain in the reinforcement; and the crack patterns in the concrete. The test structure behaved stably for cyclic loading. The test structure is analyzed to be safe in all members.
연안오염퇴적물에 함유된 유기물질과 PAHs의 현장정화를 위한 생물활성촉진제의 효능을 파일럿 규모의 현장실험을 통하여 1년간 평가하였다. 실험 해역의 수온은 계절적인 요인으로 인해 16.5°C에서 21°C까지 변화가 있었으나, 파일럿 반응조의 오염퇴적물의 pH는 8.4-8.5로 서 비교적 일정하였다. 파일럿 실험종료 후 바탕시험구와 초산, 황산이온, 질산이온을 함유한 생물활성촉진제를 주입한 오염퇴적물의 화학적 산소요구량은 각각 39% 및 79%까지 감소하였으며, 휘발성고형물은 초기 약 15 g/kg에서 7 g/kg 및 2.5 g/kg까지 각각 감소하였다. PAHs는 2- ,3- ,4- ,5-ring 과 6-ring 16PAHs를 평가하였으며, 생물활성촉진제를 주입한 오염퇴적물에서 2-ring 화합물인 나프탈렌은 실험시작 2개월 후 100%(바탕시험구의 감소율 55.6%)까지 감소되어 가장 빨랐고, 12개월 후 3-ring 및 4-ring PAHs의 감소율은 모두 100%(바탕시험구의 감 소율 46%-100%)에 달하였다. 5-ring과 6-ring PAHs의 12개월 후의 감소율은 바탕시험구와 생물활성촉진제를 투여한 오염퇴적물에서 각각 26%-87% 및 77%-100%로 평가되었다. 연안오염퇴적물에 투입한 생물활성촉진제는 유기물질 및 난분해물질인 PAHs의 제거속도를 향상시킬 수 있는 것으로 평가되었다.
본 연구는 해상교통관제사(이하 ‘VTS 관제사’)의 해상교통관제(Vessel Traffic Service: 이하 ‘VTS’) 수행 속성을 상황인식 (situation awareness: 이하 ‘SA’)과 관련된 세부 과제들의 수행 빈도와 SA 역량에 대한 주관적 평가의 측면에서 살펴보기 위해 실시되었다. SA 세부 과제들에 대한 수행 빈도 자료는 3개 VTS 센터의 VTS 관제사가 보인 VTS 수행을 직접 관찰하여 수집하였고, SA 역량에 대한 주관적 평가 자료는 18개 VTS 센터에서 근무하는 VTS 관제사를 대상으로 설문조사법을 통해 수집하였다. 수행 빈도 자료는 SA의 세 수준 과 각 세부 과제에 따라 비교하였고, 주관적 평가 점수에 대해서는 VTS 관제사의 성별과 근무경력을 추가적으로 고려하여 분석하였다. 본 연구의 결과를 요약하면 다음과 같다. 첫째, VTS 관제사는 SA 수준 중 정보지각에 해당하는 과제를 가장 높은 비율로 수행하였고, 이어서 정보통합과 예측에 해당하는 과제들을 각각 유사한 수준으로 수행하는 것이 관찰되었다. 둘째, VTS 관제사는 정보를 획득하거나 통합하는 역량에 비해 미래 상황을 예측하는 역량을 상대적으로 더 낮게 평가하였다. 셋째, 성별 차이를 비교한 결과, 남성 VTS 관제사는 여성에 비해 더 높은 수준으로 자신의 SA 역량을 평가하였다. 넷째, 성별로 근무경력에 따른 주관적 평가 차이를 비교한 결과, 남성의 경우 근무경력이 15 년 이상인 VTS 관제사는 5년 미만의 VTS 관제사에 비해 SA의 모든 수준에 걸쳐 상대적으로 더 높은 주관적 평가를 보였으나, 여성의 경우 는 근무경력에 따른 주관적 평가에서의 차이가 관찰되지 않았다. 이러한 결과는 VTS 관제사의 SA 과제 수행 빈도와 SA에 대한 주관적 평 가가 SA 수준과 개인차 변인에 따라 달라질 수 있음을 시사한다.
The indoor thermal conductivity test, unfrozen water test, and freezing pressure test were conducted on soil mixed with waste vinyl aggregate (PE aggregate). Consequently, lower thermal conductivity, less unfrozen water, and lower freezing pressure resulted from higher PE aggregate mixing ratios. Furthermore, the plate loading test and frost penetration depth test were conducted on field model road with a sub-base of PE aggregate and crushed stone. As a result, the bearing capacity of the road mixed with 10% PE aggregate exceeded the requirement, whereas frost penetration depth was reduced by 39% compared to that of using crushed stone only.
국가직무능력표준(National competency standards, NCS)은 산업현장에서 직무를 수행하기 위해 요구되는 지식, 기술, 태도 등의 내용을 국가가 체계화한 것이다. NCS기반 현장중심 교육과정을 적용한 방사선과 재학생 3학년을 대상으로 일반촬영에 대한 방사선사 직무수행도를 평가하였다. 평가 결과, 모든 촬영방식에서 우수 및 충족 비율이 93% 이상으로 현장중심 교육과정이 재학생의 직무수행도 향상에 긍정적인 영향을 끼친 것으로 판단된다. CR 방식은 전체적으로 가장 우수한 평가를 받았으나 대상자 간 편차가 크고 영상기기조작능력이 부족한 것으로 평가되었고 Film 방식은 노출조건 설정 및 현상작업이 문제점으로 평가되었다. DR 방식은 우수한 평가를 받았으나 영상기기조작능력, 부속기자재운영능력이 부족한 것으로 평가되었다. 각 촬영에서 성취수준 이하의 평가요소를 교과목 운영에 보완한다면 재학생의 학업성취도 향상뿐만 아니라 졸업 후 임상에서 방사선사 직무수행도 향상에 도움이 되리라 판단 한다.
In this paper, the material characteristics of field applied green slope soil for development of vegetation shotcrete using mineral additive are evaluated. From the results, after a consolidation of certain level is proceeded, soil hardness and soil strength are not affected by ages. However, in order to ensure slope stability, the cohesion should be improved of green slope soil.
There are bolt contraction torque decision standards in KSB 0101 for high tension bolt( torque calculation method) and in KSB 0140 for general bolts(bolt torque decision general rule), But in using bolt torque decision general rule method, friction coefficients between bolt and to-be-bolted object will rule the calculated yielding contraction axle force and yielding contraction torque, making it hard to determine the contraction torque in the field.
So in other to determine the contraction torque for general bolts in field using high tension bolt torque decision method, the torque decision method for general bolt is proposed referencing high tension bolt torque decision method. And the field torque test is planned to verify the adaptability of the proposed method in the field.
The purpose of this study is to investigate the field application of Permeability recycled asphalt using Waste Asphalt Concrete and Resin. After the test construction, it was not cause problem, such as this stripping, falling and crack of pavement. Also, it was confirmed to be performance of equal or higher than of existing technology.
By amending of the special law on the safety management of the facility, coastal structures(breakwaters) has been incorporated into kinds of facilities. In this paper, a case study for condition assessment of coastal structures(breakwaters) is conducted according to the detailed guidelines established for coastal structures(breakwaters).
To verify the displacement estimation method which is based on the relation between displacement and strain, static and dynamic field test are performed on the real bridge structures. Static and dynamic displacements estimated by using strain signal are well agreed with measured one by LVDT. This study demonstrates that the displacement estimation method using strain signal can be effectively applied to the displacement measurement of bridge structures, which are crossing the river/road/railway or have high clearance.
Purpose: This study was to create and practically apply psychological skills training program(PSTP) for rhythmic gymnasts. Methods: Four rhythmic gymnasts aged ten to fifteen who are members of Korea Gymnastics Association and Office of Education in ‘G’ city were selected as research participants in 2014. They participated in PSTP for six months. Program effectiveness was examined through the questionnaire of CSAI-2, psychological skills, and self-management, list of competition result, and psychological counseling. The selected program was applied to each rhythmic gymnasts through supplementation sequence after practical skill training that reflected personal psychological skills level and characteristics. Results: Based on the data collected, nine specific psychological skills methods consisted of goal setting, breathing and relaxation, positive imagery, self-management, cognitive restructuring, self-confidence, performance routine, psychological counselling, and integrated performance routine were applied to the research participations. As they participated in PSTP, the following positive psychological effects were found to the research participant. First, participants’ competitive state anxiety was reduced. Second, participants’ psychological skills was improved. Third, participants’ self-management was enhanced. Fourth, participants’ performance was improved. Conclusion: PSTP was evaluated as an effective training program that helps rhythmic gymnasts’ psychological steadiness. Based on the result of the study, it is expected that more rhythmic gymnasts are trained using PSTP to improve their mental strongness, so that they perform their best athletic skills and talents in their competition.
Ninety ducks (one-day-old Pekins, 45 males and 45 females) were used to evaluate the effects of supplementing diets with Houttuynia cordata powder on the fatty acid profiles of duck breast meat. The ducks were allotted to one of the three treatment diets using a completely randomized design, each treatment-group containing three replicate pens with ten birds each (five of each gender). The experimental diets were: 1) Control (basal diet), 2) T1 (Control+ 1% Houttuynia cordata) and 3) T2 (Control+2% Houttuynia cordata). In spite of significant difference, the addition of Houttuynia cordata resulted in higher unsaturated fatty acid and lower saturated fatty acid contents than in the Control group. However, no remarkable difference was observed between 1% and 2 % Houttuynia cordata groups for fatty acid profiles.
After carrying out on-the-spot observation targeting each farmhouse of large-scale environment-friendly agricultural district (LEAD), Suncheon, Sancheong, Jangheung, Yeongam, Hamyang, Okcheon, and Jeongseon in 2015, only one LEAD, a farmhouse in Jangheung had used sustainable compost coming out under their own non-antibiotic livestock. The soil pH and EC at a depth of 0-20 cm in the seven LEADs were ranged between 5.3-6.6 and 0.4-1.2 dS m-1, respectively, with 0.03- 0.27% for T-N concentration, 22-322 mg kg-1 for P, and 0.05-0.29 mg kg-1, which were, in particular, low a farmhouse in Jeongseon. When intensively surveying on each farmhouse of Suncheon, Jangheung, and Okcheon for a growing period, seasonal soil pH was maintained above 6.0 and high in a farmhouse in Okcheon, with similar soil EC observed among the three LEADs. Seasonal soil T-N was 0.1% higher on the farmhouse in Suncheon than other two LEADs, with higher seasonal soil P observed on the farmhouse in Okcheon and higher soil K in the Jangheung. T-N concentration in rice (Oryza sativa L.) crops was the highest in Jangheung, and concentrations of T-N, P, and K decreased in a season. Plant height and number of tillers per hill were the highest on the farmhouse in Okcheon, where was similar or low plant diameter and SPAD levels compared to other two LEADs. Dry weight (DW) before harvest was ranged between 52-63 g, and DW, rough rice yield (kg), brown rice/rough rice (%), brown rice yield (kg), head rice (%), and broken rice (%) were not significantly different among the three LEADs. Total annual gross production ha-1 was the highest on the farmhouse in Okcheon (16,230,000 won) planting with high class of variety, ‘Milky queen’ atearly maturation, which was expected to be increased on an agricultural income. However, high amount of fertilizer was applied for growing the following crops on the farmhouse in Okcheon, affecting the highest balance of T-N, P, and K more than 200 kg ha-1.