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Analytical Method of Partial Standing Wave-Induced Seabed Response in Finite Soil Thickness under Arbitrary Reflection (임의반사율의 부분중복파동장에서 유한두께를 갖는 해저지반 내 지반응답의 해석법)

  • Lee, Kwang-Ho;Kim, Do-Sam;Kim, Kyu-Han;Kim, Dong-Wook;Shin, Bum-Shick
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.26 no.5
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    • pp.300-313
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    • 2014
  • Most analytical solutions for wave-induced soil response have been mainly developed to investigate the influence of the progressive and standing waves on the seabed response in an infinite seabed. This paper presents a new analytical solution to the governing equations considering the wave-induced soil response for the partial standing wave fields with arbitrary reflectivity in a porous seabed of finite thickness, using the effective stress based on Biot's theory (Biot, 1941) and elastic foundation coupled with linear wave theory. The newly developed solution for wave-seabed interaction in seabed of finite depth has wide applicability as an analytical solutions because it can be easily extended to the previous analytical solutions by varying water depth and reflection ratio. For more realistic wave field, the partial standing waves caused by the breakwaters with arbitrary reflectivity are considered. The analytical solutions was verified by comparing with the previous results for a seabed of infinite thickness under the two-dimensional progressive and standing wave fields derived by Yamamoto et al.(1978) and Tsai & Lee(1994). Based on the analytical solutions derived in this study, the influence of water depth and wave period on the characteristics of the seabed response for the progressive, standing and partial standing wave fields in a seabed of finite thickness were carefully examined. The analytical solution shows that the soil response (including pore pressure, shear stress, horizontal and vertical effective stresses) for a seabed of finite thickness is quite different in an infinite seabed. In particular, this study also found that the wave-induced seabed response under the partial wave conditions was reduced compared with the standing wave fields, and depends on the reflection coefficient.

A Study on the Effects of Career Interrupted Women' Personal Attitude and Subjective Norm on Entrepreneurial Intention: Focusing on Moderating Effects on the Entrepreneurial Supporting Policy (경력단절여성의 창업행위에 대한 태도와 주관적 규범이 창업의도에 미치는 영향)

  • Choi, Jinsook;Lee, Namhee;Hwang, Kumju
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.14 no.4
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    • pp.113-132
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    • 2019
  • The degree of females' participation in corporate activity has been recently increased over the world and females' participation in economic activity may be new dynamic fuel for the Korean economy that falls into the vicious cycle of low growth. Start-up, therefore, has increasingly taken attention as an opportunity for females whose careers were interrupted to re-enter the labor market. The need for studies that examine factors influencing the decision of start-up is also increased along with the increase of the ratio of females' start-up. This study aims to verify effects of the women's characteristics(women discrimination, women's role conflict) and the human networks of females whose careers were interrupted, with the intention for entrepreneurial intention, which are mediated by personal attitudes and subjective norm suggested by Ajzen's Theory of Reasoned Action, based on an empirical research. The findings show that the human networks of females have an effect on attitudes toward start-up activity and subjective norm and the woman discrimination influence the personal attitudes. In contrast, the women's role conflict have no effect on both personal attitude toward start-up activity and subjective norm. This can be supposed as an outcome resulted from the subjects' low level of conflict caused by their sex roles, on their age distribution. The relation between subjective norm and entrepreneurial Intention seemed to be moderated by their perceived strong entrepreneurial supporting policy. Their attitudes toward start-up activity were found to have a mediating effect on the relation between the women discrimination, human networks and entrepreneurial Intention, while the subjective norm only mediated the relation between human networks and entrepreneurial Intention. Based on such results, this study attempts to suggest theoretical suggestions and the direction of various entrepreneurial supporting policy for the increase and the growth of start-up of females whose careers were interrupted, in Korea.

Enhancing the Performance of Polypropylene Fiber Reinforced Cementitious Composite Produced with High Volume Fly Ash (폴리프로필렌 섬유로 보강된 하이볼륨 플라이애시 시멘트 복합재료의 성능 향상 기법)

  • Lee, Bang Yeon;Bang, Jin Wook;Kim, Yun Yong
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.17 no.3
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    • pp.118-125
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    • 2013
  • The synthetic fibers including Polyvinyl alcohol and Polyethylene fibers have been successfully used in the manufacture of high ductile fiber reinforced cementitious composites. Polypropylene (PP) fiber has also been used in composites, not for the purpose of achieving a high level of tensile ductility but to improve the fire resistance performance of concrete exposed to high temperatures. This paper discusses the method for enhancing the performance of composites supplemented with PP fiber. Five types of mixture proportions were designed with high volume fly ash for testing the performance of composites. Type I cement and fly ash F were used as binding materials. The water-to-binder ratio was 0.23~0.25, and the amount of PP fiber used was 2 vol%. Polystyrene bead were also used to increase the tensile ductility of composites. A series of experiments including slump, density, compression and uniaxial tension tests were performed to evaluate the performance of cementitious composites supplemented with PP fiber. From the test results, it was exhibited that the performance of composites supplemented with PP fiber can be enhanced by adopting the mechanics and statistics theory.

Analysis of Traffic Delays at Scramble Crosswalks Considering Signal Phase Sequence and Traffic Volume (신호현시 순서와 통행량을 고려한 대각선 횡단보도 지체도 분석)

  • Kim, Suji;Lee, Jooyoung;Kwon, Yeongmin
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.19 no.3
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    • pp.116-128
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    • 2020
  • This study compared the delays of scramble crosswalks and general crosswalks, considering the pedestrian and vehicle traffic at intersections. Based on the signal theory, this study used traffic delays as a measure of feasibility of installing scramble crosswalks. The road structure and length of signal lights were assumed to be specific numbers to calculate the delays in vehicles and pedestrians. With the computed delays, this study compared general crosswalks and scramble crosswalks, and evaluated the feasibility sections on the installation of scramble crosswalks using circular and non-circular signal phases, respectively. The analysis confirmed that the introduction of scramble crosswalks might be more appropriate when the traffic ratio on the main roads is high. In addition, the application of non-circular signal phases is more proper for the operation of scramble crosswalks than circular signal phases. In the non-circular signaling system, however, it was shown that diagonal crosswalks might not be practical if the demand for diagonal crossing is too low. These results are expected to contribute to the development of basic guidelines for assessing the installment feasibility of scramble crosswalks in terms of traffic operation and efficiency.

The clinical study on 37 cases of whiplash injury patients which caused by traffic accident (교통사고(交通事故)로 인한 편타성(鞭打性) 손상(損傷) 환자(患者) 37례(例)에 대한 임상연구(臨床硏究))

  • Kang, Jae-Hui;Jang, Suk-Geun;Lee, Hyun;Lee, Byung-Ryul
    • Journal of Acupuncture Research
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    • v.19 no.3
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    • pp.180-191
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    • 2002
  • Objective : This study was performed to evaluate the effect of oriental medical treatment in whiplash injury patients which caused by traffic accident. Methods : The clinical study was carried out 37 cases of whiplash injury patients which had been admitted in Daejon university Cheon-an oriental hospital from June, 2001 to December, 2001. Results : l. In the distribution of sex distinction was female much more than male in the ratio of 3:2 and thirties was most in age distribution. 2. In situation of traffic accident, The most case was rear-ending(70.27%). 3. Except cervical pain or it's reffered pain, there were whole body symptoms as fallow, insomnia in 11cases(29.73%), night pain in 10 cases(27.03%), general body pain in 8cases(21.62), dizziness in 6cases(16.22%). 4. According to Meridian Muscle theory, a injured parts of patient were devided as follows. There were 22cases(59.46%) which have injury in Bladder, Small Intestine Meridian Muscle, 10cases(27.03%) in Gallblader, Triple Energizer Meridian Muscle, 5cases(13.51%) in Stomach, Large Intestine Meridian Muscle. 5. There were 6cases(16.22%) of the grade of complete recovery, 10cases(27.03%) of the grade of excellent, 12cases(32.43%) of the grade of improvement, 6cases(16.22%) of the grade of disimprovement and 3cases(8.11%) of the grade of poor. So 28cases(75.68%) were efficacious. 6. Generally Herb-meds that have efficacy of Geo-Eohyeol were most used(27cases, 72.97%) in early stage. Secondly Herb-med that have efficacy of Yiqi-sunqi were used(20case, 54,05%) in middle stage and Herb-med of Bo-Qiheol were used(l0cases, 27.03%) in latter term. The most used Herb-med was Hoisu-san, Oyaksungi-san(22cases, 54.96%). 7. In l5cases which have Aqua-Acupuncture treatment, There were 3cases of Complete recovery, 5cases of Excellent, 4cases of Improvement, 2cases of Disimprovement, 1cases of Poor. 8cases(53.33%) were above Excellent grade, so it is more efficatious Than simple treatment without Aqua-Acupuncture(36.37%). 8. The improvement of Bladder, Small Intestine Meridian Muscle was 77.27%, Gallblader, Triple Energizer Meridian Muscle was 70% and Stomach, Large Intestine Meridian Muscle was 80%. Additional Aqua-Acupuncture treatment improved to be effective in Bladder, Small Intestine Meridian Muscle(77.78%), in Gallblader, Triple Energizer Meridian Muscle(75%), in Stomach, Large Intestine Meridian Muscle(100%). Conclusions : In this study, Oriental treatment especially Aqua-Acupuncture was effective in whiplash injury patients which caused by traffic accident.

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Analysis of Successional Trend by Transition Matrix Model in the Mixed Broadleaved-Abies Forest of Mt. Odae (추이행렬(推移行列) 모델에 의한 오대산(五臺山) 활엽수(闊葉樹)-젓나무속(屬) 혼효림(混淆林)의 천이(遷移) 경향(傾向) 분석(分析))

  • Kim, Ji Hong
    • Journal of Korean Society of Forest Science
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    • v.81 no.4
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    • pp.325-336
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    • 1992
  • The successional status and potential natural vegetation were examined in a mixed broadleaved-Abies forest located at Mt, Odae National Park. The examination was based on the subsequent process of generation replacement by understory saplings for the dominant canopy trees within 88 $5m{\times}50m$ belt transects. The transition matrix model, which was modified from mathematical theory of Markov chain, was employed to analyze the successional status of the study forest. The model suggests that the study forest is still seral, and it is considered to be more than 700 years away from the steady state or climax in terms of species composition. The simulations predict a remarkable decrease in the proportion of species composition of the present dominant Quercus mongolica and Tilia amurensi.s from current 28% and 13% to less than 3% and 5%, respectively, at the steady state. On the contrary, the proportions of Abies holophylla, Acer pseudo-sieboldianum, Carpinus cordata, and Pinus koraiensis will increase at the steady state. The ratio of mixture between deciduous and coniferous trees will be gradually changed from current 6.5 : 3.5 to 5.0 : 5.0 at equilibrium. Discussion for the problems of Quercus mongolica in successional status noted that the species behaved as a mid-successional dominant, not a climax species in the study forest. The hypothesis and sensitivity of the transition matrix model were also discussed to evaluate the applicability to the real situation. The overall results indicated that the present dynamics of the forest must reflect the seral state due to previous disturbance mainly by hyman related interference.

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Analysis of Factors Affecting Breakfast Eating Behavior of Children in Indonesia: An Application of the Health Belief Model (인도네시아 아동들의 아침식사하기에 영향을 미치는 요인 분석 -건강신념모델을 이용하여-)

  • Kang, Ran Yi;Lee, Soo Jin;Ryu, Ho Kyung
    • Korean Journal of Community Nutrition
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    • v.25 no.1
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    • pp.1-12
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    • 2020
  • Objectives: This study investigates the current state of consuming breakfast among elementary school students residing in Malang, East Java, Indonesia, and to identify factors that influence breakfast behavior. Methods: The research model was set up as per the health belief model, and slightly modified by adding the subjective normative factors of the theory of planned behavior. The survey was conducted from July 17 to August 15, 2017 using a questionnaire, after receiving the permission PNU IRB (2017_60_HR). Results: The subjects were 77 boys (49.4%) and 79 girls (50.6%) suffering from malnutrition with anemia (21.2%) and stunting ratio of Height for Age Z Score (HAZ) (11.5%). Furthermore, moderate weakness (14.8%) and overweight and obesity (12.3%) by Body Mass Index for Age Z Score (BMIZ) were coexistent. According to the results obtained for breakfast, 21.8% did not eat breakfast before school, with 18.8% of the reasons for skipping breakfast being attributed to lack of food. Even for subjects partaking breakfast, only about 10% had a good balanced diet. The average score of behavioral intention on eating breakfast was 2.60 ± 0.58. The perceived sensitivity, perceived severity, perceived benefits, and self-efficacy of the health belief model correlated with breakfast behavior. Of these, self-efficacy (β=0.447, R2=0.200) and perceived sensitivity (β=0.373, R2=0.139) had the greatest effect on breakfast behavior. Mother was the largest impact person among children. Conclusions: In order to increase the level of breakfast behavior intention among children surveyed in Indonesia, we determined the effectiveness by focus on education which helps the children recognize to be more likely to get sick when they don't have breakfast, and increase their confidence in ability to have breakfast on their own. We believe there is a necessity to seek ways to provide indirect intervention through mothers, as well as impart direct nutrition education to children.

GIS-based Data-driven Geological Data Integration using Fuzzy Logic: Theory and Application (퍼지 이론을 이용한 GIS기반 자료유도형 지질자료 통합의 이론과 응용)

  • ;;Chang-Jo F. Chung
    • Economic and Environmental Geology
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    • v.36 no.3
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    • pp.243-255
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    • 2003
  • The mathematical models for GIS-based spatial data integration have been developed for geological applications such as mineral potential mapping or landslide susceptibility analysis. Among various models, the effectiveness of fuzzy logic based integration of multiple sets of geological data is investigated and discussed. Unlike a traditional target-driven fuzzy integration approach, we propose a data-driven approach that is derived from statistical relationships between the integration target and related spatial geological data. The proposed approach consists of four analytical steps; data representation, fuzzy combination, defuzzification and validation. For data representation, the fuzzy membership functions based on the likelihood ratio functions are proposed. To integrate them, the fuzzy inference network is designed that can combine a variety of different fuzzy operators. Defuzzification is carried out to effectively visualize the relative possibility levels from the integrated results. Finally, a validation approach based on the spatial partitioning of integration targets is proposed to quantitatively compare various fuzzy integration maps and obtain a meaningful interpretation with respect to future events. The effectiveness and some suggestions of the schemes proposed here are illustrated by describing a case study for landslide susceptibility analysis. The case study demonstrates that the proposed schemes can effectively identify areas that are susceptible to landslides and ${\gamma}$ operator shows the better prediction power than the results using max and min operators from the validation procedure.

Generation of Charged Clusters and their Deposition in Polycrystalline Silicon Hot-Wire Chemical Vapor Deposition (열선 CVD 증착 다결정 실리콘에서 전하를 띈 클러스터의 생성 및 증착)

  • Lee, Jae-Ik;Kim, Jin-Yong;Kim, Do-Hyeon;Hwang, Nong-Moon
    • 한국신재생에너지학회:학술대회논문집
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    • 2005.11a
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    • pp.561-566
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    • 2005
  • Polycrystalline silicon films were deposited using hot wire CVD (HWCVD). The deposition of silicon thin films was approached by the theory of charged clusters (TCC). The TCC states that thin films grow by self-assembly of charged clusters or nanoparticles that have nucleated in the gas phase during the normal thin film process. Negatively charged clusters of a few nanometer in size were captured on a transmission electron microscopy (TEM) grid and observed by TEM. The negatively charged clusters are believed to have been generated by ion-induced nucleation on negative ions, which are produced by negative surface ionization on a tungsten hot wire. The electric current on the substrate carried by the negatively charged clusters during deposition was measured to be approximately $-2{\mu}A/cm^2$. Silicon thin films were deposited at different $SiH_4$ and $H_2$ gas mixtures and filament temperatures. The crystalline volume fraction, grain size and the growth rate of the films were measured by Raman spectroscopy, X-ray diffraction and scanning electron microscopy. The deposit ion behavior of the si1icon thin films was related to properties of the charged clusters, which were in turn controlled by the process conditions. In order to verify the effect of the charged clusters on the growth behavior, three different electric biases of -200 V, 0 V and +25 V were applied to the substrate during the process, The deposition rate at an applied bias of +25 V was greater than that at 0 V and -200 V, which means that the si1icon film deposition was the result of the deposit ion of charged clusters generated in the gas phase. The working pressures had a large effect on the growth rate dependency on the bias appled to the substrate, which indicates that pressure affects the charging ratio of neutral to negatively charged clusters. These results suggest that polycrystalline silicon thin films with high crystalline volume fraction and large grain size can be produced by control1ing the behavior of the charged clusters generated in the gas phase of a normal HWCVD reactor.

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Multi-modality MEdical Image Registration based on Moment Information and Surface Distance (모멘트 정보와 표면거리 기반 다중 모달리티 의료영상 정합)

  • 최유주;김민정;박지영;윤현주;정명진;홍승봉;김명희
    • Journal of KIISE:Computer Systems and Theory
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    • v.31 no.3_4
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    • pp.224-238
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    • 2004
  • Multi-modality image registration is a widely used image processing technique to obtain composite information from two different kinds of image sources. This study proposes an image registration method based on moment information and surface distance, which improves the previous surface-based registration method. The proposed method ensures stable registration results with low registration error without being subject to the initial position and direction of the object. In the preprocessing step, the surface points of the object are extracted, and then moment information is computed based on the surface points. Moment information is matched prior to fine registration based on the surface distance, in order to ensure stable registration results even when the initial positions and directions of the objects are very different. Moreover, surface comer sampling algorithm has been used in extracting representative surface points of the image to overcome the limits of the existed random sampling or systematic sampling methods. The proposed method has been applied to brain MRI(Magnetic Resonance Imaging) and PET(Positron Emission Tomography), and its accuracy and stability were verified through registration error ratio and visual inspection of the 2D/3D registration result images.