• Title/Summary/Keyword: total reflection

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A Planar Implementation of a Negative Group Delay Circuit (평면 구조의 마이너스 군지연 회로 설계)

  • Jeong, Yong-Chae;Choi, Heung-Jae;Chaudhary, Girdhari;Kim, Chul-Dong;Lim, Jong-Sik
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.21 no.3
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    • pp.236-244
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    • 2010
  • In this paper, a planar structure negative group delay circuit(NGDC) is proposed to overcome the limited availability of the component values required for the prototype lumped element(LE) NGDC design. From the prototype LE circuit analysis, general design equations and the conditions to obtain the NGD are derived and illustrated. Then the LE circuit is converted into the planar structure by applying the transmission line resonator(TLR) theory. As a design example, the LE NGDC and the proposed planar structure NGDC are designed and compared. To estimate the commercial applicability, 2-stage reflection type planar NGDC with -5.6 ns of total group delay, -0.2 dB of insertion loss, and 30 MHz of bandwidth together with 0.1 dB and 0.5 ns of the magnitude and group delay flatness, respectively, for Wideband Code Division Multiple Access(WCDMA) downlink band is fabricated and demonstrated. Also, to show the applicability of the proposed NGDC, we have configured a simple signal cancellation loop and obtained good loop suppression performance.

Behavior Evaluation of Thin Bonded Continuously Reinforced Concrete Overlay on Aged Jointed Concrete Pavement(2) (노후 줄눈 콘크리트 포장 보수를 위한 얇은 연속 철근 콘크리트 덧씌우기 포장의 거동 평가(2))

  • Ryu, Sung-Woo;Cho, Yoon-Ho
    • International Journal of Highway Engineering
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    • v.12 no.4
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    • pp.101-110
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    • 2010
  • In this paper, it has been studied about the CRCO to maintain or rehabilitate the aged JCP. The CRCO and JCO was constructed at useless section of Seo-Hae-Ahn express highway in South Korea. The performance evaluation was conducted. Especially, it was focused on the roll of longitudinal reinforced steels inserted into the CRCO. On crack survey results from field construction section, the reflection cracks at joint of the existing pavement occurred in CRCO. However, due to the constraints of longitudinal reinforced steels, crack width was small. Total crack length and quantity in the CRCO more than that in the JCO. And crack spacing in the CRCO was narrower than it in the CRCP. Through the bonding strength test results, if the cold milling and cleaning as well as surface treatment is applied, there will be no debonding problem at interlayer in the early age. From analysis of the horizontal behavior at the joint, the longitudinal reinforced steels constrained crack width which became wider than initial state over time. Also, that steel in the CRCO reduced the horizontal movement due to temperature variation(4 times than that in the JCO). But, if interface is debonded, the roll decreased. Vertical VWG data showed that CRCO did not occur debonding problem at steel location, but there was some problem in JCO. It was confirmed by field coring. The tensile strain appeared in the CRCO, But the compressive strain occurred in the JCO in early age. Through the FWD test result, deflection in the CRCO was less than that in the JCO. And K value in the CRCO was greater than it in the JCO.

A case study of family therapy about conflict between mother and the eldest son (홀어머니와 큰아들의 갈등에 대한 가족치료 사례연구)

  • Park, Tai-young;Kim, Tae-han
    • Korean Journal of Family Social Work
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    • no.23
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    • pp.263-302
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    • 2008
  • The study had four purposes as follows; First, the researcher tried to find the characteristics of conflict. Second, the researcher attempted to find the factors influencing the conflict between mother and the eldest son, Third, the study attempted to find the therapist's intervention techniques, which were caused the change of the conflict between mother and the eldest son. Lastly, the study was to find the changed contents of family relationships. The total family counseling was 13 sessions, which included individual and family counseling. The study used constant comparative analysis by using open coding method to find the factors. Also, the researcher used Miles and Huberman's matrix and graphical network display to show the relationships among factors influencing the conflicts between mother and the eldest son. The study found the boundary problem of family, family's undifferentiated ego, dysfunctional communication patterns, and mother's experience from family of origin as factors influencing the conflict between mother and the eldest son. On the other hand, the study found that the therapist used the formation of therapeutic alliance relationship, guide of communication skills, the reflection of repeated pattern, reframing and a metaphor as intervention methods. The result of study revealed that changed level of family relationship, activating functional communication, changed boundary among family members, differentiated ego of family members, and changed cognition as the changed contents of family relationship.

New Methods for Correcting the Atmospheric Effects in Landsat Imagery over Turbid (Case-2) Waters

  • Ahn Yu-Hwan;Shanmugam P.
    • Korean Journal of Remote Sensing
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    • v.20 no.5
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    • pp.289-305
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    • 2004
  • Atmospheric correction of Landsat Visible and Near Infrared imagery (VIS/NIR) over aquatic environment is more demanding than over land because the signal from the water column is small and it carries immense information about biogeochemical variables in the ocean. This paper introduces two methods, a modified dark-pixel substraction technique (path--extraction) and our spectral shape matching method (SSMM), for the correction of the atmospheric effects in the Landsat VIS/NIR imagery in relation to the retrieval of meaningful information about the ocean color, especially from Case-2 waters (Morel and Prieur, 1977) around Korean peninsula. The results of these methods are compared with the classical atmospheric correction approaches based on the 6S radiative transfer model and standard SeaWiFS atmospheric algorithm. The atmospheric correction scheme using 6S radiative transfer code assumes a standard atmosphere with constant aerosol loading and a uniform, Lambertian surface, while the path-extraction assumes that the total radiance (L/sub TOA/) of a pixel of the black ocean (referred by Antoine and Morel, 1999) in a given image is considered as the path signal, which remains constant over, at least, the sub scene of Landsat VIS/NIR imagery. The assumption of SSMM is nearly similar, but it extracts the path signal from the L/sub TOA/ by matching-up the in-situ data of water-leaving radiance, for typical clear and turbid waters, and extrapolate it to be the spatially homogeneous contribution of the scattered signal after complex interaction of light with atmospheric aerosols and Raleigh particles, and direct reflection of light on the sea surface. The overall shape and magnitude of radiance or reflectance spectra of the atmospherically corrected Landsat VIS/NIR imagery by SSMM appears to have good agreement with the in-situ spectra collected for clear and turbid waters, while path-extraction over turbid waters though often reproduces in-situ spectra, but yields significant errors for clear waters due to the invalid assumption of zero water-leaving radiance for the black ocean pixels. Because of the standard atmosphere with constant aerosols and models adopted in 6S radiative transfer code, a large error is possible between the retrieved and in-situ spectra. The efficiency of spectral shape matching has also been explored, using SeaWiFS imagery for turbid waters and compared with that of the standard SeaWiFS atmospheric correction algorithm, which falls in highly turbid waters, due to the assumption that values of water-leaving radiance in the two NIR bands are negligible to enable retrieval of aerosol reflectance in the correction of ocean color imagery. Validation suggests that accurate the retrieval of water-leaving radiance is not feasible with the invalid assumption of the classical algorithms, but is feasible with SSMM.

A Design and Effect of Design Thinking-Based Team Project Learning in Nursing Clinical Practice (간호학 임상실습에서 디자인씽킹 기반 팀 프로젝트 학습 설계 및 적용효과)

  • Kang, Myung-Ju;Chung, Kyung-Hee;Cho, Jeong-Ah
    • The Journal of the Korea Contents Association
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    • v.19 no.3
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    • pp.336-348
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    • 2019
  • This study aimed to verify the effects of design thinking-based team project learning on nursing college students' empathy and proactivity of problem solving. This study also examined the subjects' experiences obtained from participating in team project activity through reflective analysis. The research was a one-group, pre-and-posttest design. The subjects were 64 seniors majoring in nursing studies in N university who had attended the course of nursing management practice. During the course, they participated in a design thinking team project for a total of 10 sessions for two weeks, five times per week, and one and a half hour per day. Data was analyzed using SPSS Win 22.0, a paired t-test was conducted and Pearson's correlation coefficients were calculated. Content analysis was carried out on their experiences obtained from participation in team project activity. The subjects' empathy(t=-2.94, p=.005) and proactivity of problem solving(t=-6.23, p<.001) showed statistically significant difference between before and after the design thinking-based team project learning and had significant positive correlation(r=.634, p<.001). Analysis of team reflection revealed four themes: design thinking, empathy, problem solving ability, and critical thinking. This study verified that design thinking-based team project learning was very effective in developing nursing college students' empathy and proactivity of problem solving. Research Results Design Thinking Based on team learning, project learning is an effective teaching learning method for finding and defining customer needs, creating a solution to problems, and enhancing engagement and empathy through various stakeholder collaborations I could.

Effect of Fingertip Temperature on Multi-finger Actions in Young Adults (손 끝 온도변화가 젊은 성인의 다중 손가락 동작에 미치는 효과)

  • Shin, Narae;Xu, Dayuan;Song, Jun Kyung;Park, Jaebum
    • Korean Journal of Applied Biomechanics
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    • v.29 no.3
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    • pp.157-166
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    • 2019
  • Objective: This study examined the effects of stimulating fingertip temperature on the patterns of force sharing and stability properties during multi-finger force production tasks. Method: 9 adult subjects (male: 3, female: 6, age: $26.11{\pm}4.01yrs$, height: $169.22{\pm}5.97cm$, weight: $61.44{\pm}11.27kg$) participated in this study. The experiment consisted of three blocks: 1) maximal voluntary contraction (MVC) task, 2) single-finger ramp task to quantify enslaving (i.e., unintended force production by non-task fingers), and 3) 12 trials of multi-finger steady-state force production task at 20% MVC. There were three temperature conditions including body-temperature (i.e., control condition), $40^{\circ}C$, and $43^{\circ}C$, and the stimulation was given to the index finger only for all experimental conditions. Results: There were no significant differences in the MVC forces, enslaving, and the accuracy of performance during the steady-state task between the conditions. However, the share of stimulated index finger force increased with the index fingertip temperature, while the share of middle finger force decreased. Also, the coefficient of variation of both index and middle finger forces over repetitive trials increased with the index fingertip temperature. Under the framework of the uncontrolled manifold (UCM) hypothesis used to quantify indices of multi-finger synergies (i.e., stability property) stabilizing total force during the steady-state task, the two variance components within the UCM analysis increased together with the fingertip temperature, while no changes in the synergy indices between the conditions. Conclusion: The current results showed that fingertip temperature stimulation only to index finger does not affect to muscle force production capability of multi-finger, independence of individual fingers, and force production accuracy by the involvement of all four fingers. The effect of fingertip temperature on the sharing pattern and force variation may be due to diffuse reflex effects of the induced afferent activity on alpha-motoneuronal pools. However, the unchanged stability properties may be the reflection of the active error compensation strategies by non-stimulated finger actions.

Scale Revalidation Study for Online Use of the Learning Strategy Diagnostic Scale for Junior College (전문대학생용 학습전략 진단 척도의 온라인 활용을 위한 재타당화 연구)

  • Hwang, Jae Gyu
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.1
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    • pp.349-359
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    • 2022
  • The purpose of this study is to add and revalidate items of learning cognition and learning emotion factors for online use of the K-LSS for junior college. It is important for self-reflection and improvement of academic achievement to specifically explore and analyze the sub-factors of learning cognition, learning behavior, and learning emotion for each item that can affect the learning strategy of junior college students. The added items are two items for diagnosing the concentration of attention in the learning information processing process of the learning cognitive factor and two questions about the interpersonal anxiety factor for diagnosing the level of anxiety about others in the learning emotional factor. The study area was conducted in 5 areas nationwide, and the subjects of the study were 923 junior college students excluding 327 respondents who answered insincerity. The K-LSS_r scale is a learning strategy diagnosis scale of 52 questions composed of three sub-elements of learning cognition (18 questions), learning emotion (15 questions), and learning behavior (19 questions), and reliability for generalization in this study. As a result of the verification, Cronbach's α coefficient of the entire scale was .896, and Cronbach's α coefficient of the three factors ranged from .876 to .910. The half-segment reliability coefficient of the scale was .858 in total, and the half-segment reliability coefficients of the three factors ranged from .792 to .843. The test-retest reliability verification result for 3 weeks for 350 Junior college Students in 5 regions was .884, and the validity test for generalization also confirmed that the recruitment validity is significant.

Exploring the Direction of Improvement in Consideration of the Talent Image of Each School in the Science High School Admissions (과학고등학교 입학전형에서 학교별 인재상을 고려하는 개선 방향 탐색)

  • Hwang, Dahyeon;Son, Jeongwoo
    • Journal of The Korean Association For Science Education
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    • v.42 no.1
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    • pp.51-60
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    • 2022
  • This study aims to explore the direction of improvement that considers the talent image of science high schools in the admissions process. To this end, first, the talent image and competencies of science high schools were divided into 'publicity' and 'efficiency,' 'execution' and 'achievement' types, and 'publicity & execution' was predominant in most cases. Next, a total of 28 science high school teachers, education experts, and middle school teachers were surveyed on the degree of reflection of talent image and the direction of improvement in the admissions process of three science high schools. The results of the survey are as follows: first, the evaluation of 'publicity' was very limited in the first stage of admissions process, and selection based on 'achievement' was high. Second, there was a strong tendency to select based on 'efficiency & achievement' in the second stage of interview evaluation. Third, we need to improve the selection of students who fit the 'publicity & execution' type of talent image by introducing 'publicity & execution' type of talent image by introducing 'write a competency-oriented self-introduction letter, reflect other subjects' grades and comparative studies in the school life record, and experts' interviews' to the first-stage of admissions process. Fourth, convergence and open-ended questions that enable divergent thinking should be jointly submitted to reflect the 'publicity & execution' type of talent image in the second stage of interview evaluation. In conclusion, the direction of improvement that considers the talent image of science high schools in the admissions process should be changed to competency-oriented in the first-stage of admissions process and in the second stage of interview evaluation consisting of open-ended questions.

A study on communication process with team members perceived by team leader in corporation (기업 팀장이 인식하는 팀원과의 의사소통 과정 연구)

  • Baek, Eun Jung;Shin, Hyo Jung
    • The Korean Journal of Coaching Psychology
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    • v.5 no.2
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    • pp.25-51
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    • 2021
  • The purpose of this study is to deeply explore the communication process with team members perceived by team leader. To this end, in-depth interviews were conducted with 10 team leaders, and analyzed according to the grounded theory research method procedure suggested by Strauss and Corbin. As a results, a total of 51 concepts, 17 subcategories, and 8 categories were derived. As a causal condition, the concept of 'contemplating and reinterpreting communication necessary for the organization' was derived, and the central phenomenon was 'intentional effort made in parallel with work and private conversations'. The contextual condition was 'recognizing the need to cope with environmental changes', and the mediating condition was 'self-reflection and self-coaching time' was derived. The action/interaction strategy was conceptualized as a communication process with task-oriented coping, conflict resolution coping, and relationship promotion coping, and was confirmed as 'recognizing virtuous cycle communication within the organization' as a result of interaction with the central phenomenon. As a result of analysis of the team leader's communication process, the effort stage, approach stage, coping stage, and cycle stage were shown. As a result of the type analysis, task-oriented coping was a facilitator, conflict resolution coping was a supporter, and relationship promotion coping was a considerate. This study is an empirical study on how the corporate team leader perceives and expresses communication in the relationship with the team members.

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A Research on the Creation of Floral Art Works Applying Characteristics of Contemporary Materials (현대적 소재의 특징을 활용한 화예작품 창작에 관한 연구)

  • Yun, Hwa Jin;Yoo, Taek Sang
    • Journal of the Korean Society of Floral Art and Design
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    • no.41
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    • pp.115-132
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    • 2019
  • Today, the expansion of the possibility of new expressions of plastic arts is largely due to emergence and application of new materials. In the field of flower design, it is found that there is a tendency to seek a new expression by utilizing various new materials instead of natural material that used in the past. This study is an attempt of applying methodological approach in the creation of floral art works utilizing the characteristics of contemporary materials in such context. The researcher gathered cases of specific effect and sensation in the expression of art works using various contemporary materials and extracted the characteristics using descriptive sentences applying behavior setting analysis technique. Reporting detailed result of the research total 100 guidelines under 41 sub-categories, 24 mid-categories, and 6 top categories such as transparency, lighting, combination of objects, combination of materials, reflection, shape construction. The researcher tested the effectiveness of the theories by applying deducted theories as the guidelines in creation process of her own floral art works. The significance of this study lies at experimenting the possibilities of applying methodological approach which could supplement intuitive approach in pursuit of expression for artists in the field of floral art and design.