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Development of spatial dependence formula of FORGEX method using rainfall data in Korea (우리나라 강우 자료를 이용한 FORGEX 기법의 공간상관식 개발)

  • Kim, Sunghun;Ahn, Hyunjun;Shin, Hongjoon;Heo, Jun-Haeng
    • Journal of Korea Water Resources Association
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    • v.49 no.12
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    • pp.1007-1014
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    • 2016
  • The FORGEX (Focused Rainfall Growth Extension) method was developed to estimate rainfall quantiles in the United Kingdom. This method does not need any regional grouping and can estimate rainfall quantiles with relatively long return period. The spatial dependence formula (ln $N_e$) was derived to consider the distance from growth curve of proper population to the distributed network maximum (netmax) data using the UK rainfall data. For this reason, there is an inaccurate problem in rainfall quantiles when this formula is applied in Korea. In this study, the new formula was derived in order to improve such shortcomings using rainfall data of 64 sites from the Korea Meteorological Administration (KMA). A 42-year period (1973~2014) was taken as the reference period from rainfall data, then the formula was derived using three parameters such as rainfall duration, number of site, area of network. Then the new formula was applied to the FORGEX method for regional rainfall frequency analysis. In addition, rainfall quantiles were compared with those from the UK formula. As a result, the new formula shows more accurate results than the UK formula, in which the FORGEX method by the UK formula underestimates rainfall quantiles. Finally, the new improved formula may estimate accurate rainfall quantiles for long return period.

Estimation of Dynamic Vertical Displacement using Artificial Neural Network and Axial strain in Girder Bridge (인공신경망과 축방향 변형률을 이용한 거더 교량의 동적 수직 변위 추정)

  • Ok, Su Yeol;Moon, Hyun Su;Chun, Pang-Jo;Lim, Yun Mook
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.34 no.6
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    • pp.1655-1665
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    • 2014
  • Dynamic displacements of structures shows general behavior of structures. Generally, It is used to estimate structure condition and trustworthy physical quantity directly. Especially, measuring vertical displacement which is affected by moving load is very important part to find or identify a problem of bridge in advance. However directly measuring vertical displacement of the bridge is difficult because of test conditions and restriction of measuring equipment. In this study, Artificial Neural Network (ANN) is used to suggest estimation method of bridge displacement to overcome constrain conditions, restriction and so on. Horizontal strain and vertical displacement which are measured by appling random moving load on the bridge are applied for learning and verification of ANN. Measured horizontal strain is used to learn ANN to estimate vertical displacement of the bridge. Numerical analysis is used to acquire learning data for axis strain and vertical displacement for applying ANN. Moving load scenario which is made by vehicle type and vehicle distance time using Pearson Type III distribution is applied to analysis modeling to reflect real traffic situation. Estimated vertical displacement in respect of horizontal strain according to learning result using ANN is compared with vertical displacement of experiment and it presents vertical displacement of experiment well.

THREE-DIMENSIONAL ANALYSIS OF THE NORMAL DENTITION AND EDENTULOUS MAXILLA OF KOREANS (한국인의 상악 유치악 치열 및 무치악 치조제에 관한 삼차원적 연구)

  • Kim Hyeong-Seop;Shin Sang-Wan
    • The Journal of Korean Academy of Prosthodontics
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    • v.43 no.2
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    • pp.191-203
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    • 2005
  • Statement of problem. In Korea, the preliminary impression trays for dental and edentulous maxillae are manufactured on the base of the statistical value of Westerners. There had been less study on the dental and edentulous arches of Koreans. Purpose. The purpose of this study was to evaluate an average dental cast, preliminary impression trays, three-dimensional relation of dental and edentulous maxilla of Koreans Material and methods. The subjects for this study were 173 dental casts of maxilla (dental: 52, edentulous : 146) with ages $18\{\sim}60$ years old. Each of the master casts was measured 69 measuring points on the dental cast or maxilla, and 46 measuring points on the edentulous cast of maxilla with three-dimensional digital measuring machine. Each measuring points were analysed and were overlapped, that three dimensional dental graphic manufactured by CAD/CAM system. Results. 1. A standard of distribution to alveolar bone were width between left and right buccal border lines of the standard 3/4 line. The mean value of dental and edentulous casts were 67.27mm, 63.49mm respectively. 2. Morphological classification of dental casts were divided into three groups or V-shape, O-shape, U-shape, that proportion of distribution were 17%, 16%, 67%, respectively. Dimensional classification of the dental casts were divided into five groups of less than 63mm, 63 up to 65mm, 65 up to 67mm. 67 up to 69mm, more than 69mm, respectively. 3. Morphological classification of edentulous casts were divided into three groups or V-shape, O-shape, U-shape, that proportion of distribution were 18%, 17%, 65%, respectively Dimensional classification of the edentulous casts were divided into five groups of less than 57mm, 57 up to 61mm, 61 up to 65mm, 65 up to 69mm, more than 69mm, respectively. 4. Mean dental and edentulous cast of maxilla were overlapped, the proportion of bone resorption to alveolar bone is higher than that of palatal bone, its difference were higher anterior 2/4 area than posterior 3/4 area. Conclusion. It obtains information of preliminary impression trays for dental and edentulous maxilla of Koreans.

Biomechanical evaluation of dental implants with different surfaces: Removal torque and resonance frequency analysis in rabbits

  • Koh, Jung-Woo;Yang, Jae-Ho;Han, Jung-Suk;Lee, Jai-Bong;Kim, Sung-Hun
    • The Journal of Advanced Prosthodontics
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    • v.1 no.2
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    • pp.107-112
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    • 2009
  • STATEMENT OF PROBLEM. Macroscopic and especially microscopic properties of implant surfaces play a major role in the osseous healing of dental implants. Dental implants with modified surfaces have shown stronger osseointegration than implants which are only turned (machined). Advanced surface modification techniques such as anodic oxidation and Ca-P application have been developed to achieve faster and stronger bonding between the host bone and the implant. PURPOSE. The purpose of this study was to investigate the effect of surface treatment of titanium dental implant on implant stability after insertion using the rabbit tibia model. MATERIAL AND METHODS. Three test groups were prepared: sandblasted, large-grit and acid-etched (SLA) implants, anodic oxidized implants, and anodized implants with Ca-P immersion. The turned implants served as control. Twenty rabbits received 80 implants in the tibia. Resonance frequencies were measured at the time of implant insertion, 2 weeks and 4 weeks of healing. Removal torque values (RTV) were measured 2 and 4 weeks after insertion. RESULTS. The implant stability quotient (ISQ) values of implants for resonance frequency analysis (RFA) increased significantly (P <. 05) during 2 weeks of healing period although there were no significant differences among the test and control groups (P >. 05). The test and control implants also showed significantly higher ISQ values during 4 weeks of healing period (P < .05). No significant differences, however, were found among all the groups. All the groups showed no significant differences in ISQ values between 2 and 4 weeks after implant insertion (P >. 05). The SLA, anodized and Ca-P immersed implants showed higher RTVs at 2 and 4 weeks of healing than the machined one (P < .05). However, there was no significant difference among the experimental groups. CONCLUSION. The surface-modified implants appear to provide superior implant stability to the turned one. Under the limitation of this study, however, we suggest that neither anodic oxidation nor Ca-P immersion techniques have any advantage over the conventional SLA technique with respect to implant stability.

Eligibility Analysis of Land on a Reforestation CDM Project in Goseong District, South Korea (청정개발체제하 재 조림 사업의 토지적격성에 대한 사례 분석 -고성군 재조림 사업을 중심으로-)

  • Guishan, Cui;Kwon, Tae-Hyub;Lee, Woo-Kyun;Kwak, Hanbin;Nam, Kijun;Song, Yongho;Hangnan, Yu
    • Journal of Korean Society of Forest Science
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    • v.102 no.2
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    • pp.216-222
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    • 2013
  • For reducing greenhouse gases, many countries carried out a series of activities not only at home but abroad. Particularly, after the release of the Kyoto Protocol, either nation or companies' participation was intensified, due to endow to responsibility of emission limits. This study focused on reforestation CDM work in Goseong Gun based on clean development system. Obstacle factors of land eligibility could be distinguished to three periods: before December 31th 1989, present and future. The obstacle before December 31th 1989 was that land cover of study area hardly illustrated by Landsat image, due to the low resolution, which were confirmed by a document of Grassland Composition Permission instead. The problem of current land eligibility is that the area of trees presence are difficult to be determined as forest or not. The boundary of forest in strata was identified, using 3-Dimensional Cartography Machine and aerial photograph. Land eligibility would still have obstacle whether the study area with trees presence has potentiality to be forest in the future at situation in absence of reforestation project. This was resolved by prediction of tree growth using stem analysis during execution of the project at study area.

An Empirical Approach for Gamer's Cognitive Model on Game Playing Experience : Towards Difference of Gamers' Expertise in World Warcraft Game (게임플레이 경험에 대한 게이머의 인지적 모형에 관한 실증적 접근 : World of Warcraft 게임에서 게이머의 전문성 차이를 중심으로)

  • Song, Seung-Keun
    • Journal of Korea Game Society
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    • v.9 no.3
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    • pp.23-33
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    • 2009
  • This study aims to uncover the gamers' cognitive process during the gameplay and explore the differences between groups in the gamers' playing behavior according to their expertise: experts, intermediate players, and novices. To this end, the empirical experiment was conducted in 'World of Warcraft' game which is a good representative of MMO(Massively Multi-player Online) game currently. Verbal protocol and action protocol collected from the empirical experiment were analyzed according to the gamers' expertise. As a result of this study, we found that the different behavior patterns result from standardizing pattern of their actions for experts and forming the learning curves and the specific patterns of action for intermediate game players and novices. While three functional-actions as a collection action concentrates on the early stage of the game for experts, the novices' behavior pattern dispersedly appeared in all seven functional-action, such as search, combat, three type collections, avoid, and communication in the whole gameplay. This study represents the consistency and the difference derived from the comparison analysis between groups according to the expertise. This study is concluded with key implications to support game design guidelines according to experts, intermediate players, and novices. Consequently, the result of this study provides the basic to the development of MMO content for game novices.

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Occupational Therapy Intervention for Improving Play of Children : A Systematic Review (아동의 놀이 향상을 위한 작업치료 중재에 관한 체계적 고찰)

  • Lee, Sun-Hee;Park, Hae Yean
    • The Journal of Korean Academy of Sensory Integration
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    • v.15 no.2
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    • pp.93-106
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    • 2017
  • Objective : The purpose of this study is to provide an evidence for clinical practice by systemic analysis on occupational therapy interventions for improvement of children's play. Methods : Articles used in this study were collected from database of Pubmed, ProQuest, EBSCOhost, Scopus, RISS, KISS, and National Library of Korea. The key words used in the search were "Play AND Occupational Therapy AND (Intervention OR Treatment)" and the publication period was limited from January 2007 to April 2017. 11 articles in total were selected for the systematic review analysis. Results : The results revealed that the majority of studies was one-group non-randomized study and the majority of intervention used was play-based intervention in case of that play itself was the intervention goal. The most frequently used environment for the intervention was parallel setting of home and treatment room. The majority of studies was for children with ADHD and the most commonly used assessment tool was Test of Playfulness (ToP). Dependent variables measured along with play were language skills, social interactive skills, communication and pragmatic skills, problem-solving skills, caregiver responsiveness, and parent-child interaction. Conclusion : This study help to understand the current state of occupational therapy intervention for improvement of children's play. Starting with the understanding, it is expected that various studies on play of children will be done in the future.

Descriptive Study on the Development of Educational Program for Mothers with Children who have had Open Heart Surgery in Congenital Heart Disease (개심술을 받은 심기형 환아모의 교육프로그램 개발을 위한 조사연구)

  • Lee, Kun-Ja;Jo, Hyun-Sook
    • The Korean Journal of Rehabilitation Nursing
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    • v.4 no.1
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    • pp.73-83
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    • 2001
  • The aims of this study were to identify the mothers educational needs when they have children who have had open heart surgery in congenital heart disease, to identify the children's characteristics with this problem, and also to provide the basic information on the development of the educational program for the mothers. The subjects of the study were 101 mothers of children and their children hospitalized with congenital heart disease in pediatric wards of G. University Hospital in Inchon and S. Hospital in Puch on from June to November 2000. The study used a Likert-type questionnaire with 39 questions which was based on a previous questionnaire developed by Lee Mi-ryun(1989) for adult open heart surgery patients. The reliability of the questionnaire was Cronbach' ${\alpha}$=.9375. The data were collected directly from mothers of the patients in wards. The t-test, ANOVA was adopted for the data analysis. The key results of the study are as follows : 1) The average age of the children was 32.90 months. The majority of the children are male and weighted 3.0-3.5Kg at birth. Most of the children had VSD(29.7%), and 10.9% of children had a family history of heart disease. 2) An average score of 4.62 out of a maximum of 5.00 was recorded for the educational needs of the children's mother. The highest score of 4.69 was for home care after discharge followed by a score of 4.67 for diagnosis and prognosis on congenital heart disease. And pre-post operation care scored 4.51. The mean scores of single-question items of educational need were, in order, 4.81 for immunization after operation, 4.80 for recovery process, and 4.77 for prognosis of the disease. The score of 4.18 for measurement of intake and output was the lowest. 3) The analysis on the children's mothers educational needs by social-demographic characteristics such as sex, age of patient and mother, economical status, educational status, number of child, hospitalization times, and hospitalization cause showed no significant difference statistically, but there was a significant difference between mothers with jobs and with out jobs.

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Impact of Conflict and Nurturing Factors for the Divorced Parents on the Behavioral Adaptation of their Children (이혼가정자녀의 행동적응문제에 영향을 미치는 부모요인과 아동의 이혼지각 분석)

  • Joo, So-Hee;Cho, Sung-Woo
    • Korean Journal of Social Welfare
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    • v.56 no.4
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    • pp.215-238
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    • 2004
  • The purpose of this paper is to examine the impact of conflict and nurturing factors for the divorced parent on the behavioral adaptation of their children. The participants in this study include 216 children in divorced families nationwide. Structural Equation Modeling with LISREL8 was used for statistical method. In order to achieve the purpose, researchers firstly tried to test a construct validity of conceptual variables(parental conflict, negative attitude of parental nurturing, child's belief about parental divorce, child's aggression and child's delinquence) by employing exploratory factor analysis(EFA) and confirmatory factor analysis(CFA). Result showed that all the five conceptual variables were discriminated. It was identified as the fit index of path structure was good(CFI=.955, NNFI=.947, RMSEA=.046). The specific result were as follows: 1. the parental conflict(${\xi}1$) was directly related to the negative attitude of parental nurturing(${\eta}1$) and the child's belief about parental divorce(${\eta}2$). 2. the parental conflict(${\xi}1$) was indirectly related to child's belief about parental divorce(${\eta}2$), the child's aggression(${\eta}3$) and delinquence(${\eta}4$). 3. the negative attitude of parental nurturing(${\eta}1$) was directly related to the child's belief about parental divorce(${\eta}2$). 4. the negative attitude of parental nurturing(${\eta}1$) was indirectly related to the child's aggression(${\eta}3$) and delinquence(${\eta}4$). Lastly, and, the child's belief about parental divorce(${\eta}2$) was directly related to the child's aggression(${\eta}3$) and delinquence(${\eta}4$). Researchers also identified the mediating effect of the parental nurturing between parental conflict and child's belief about parental divorce. On the basis of these results, this article provided some suggestions for promoting of children welfare.

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A Systematic Approach to Port related Problems An Analysis on the Actual Condition of physical Distribution System of Pusan port (항만관련문제의 시스템적 고찰 부산항 물류시스템의 실태분석)

  • Lee Cheol-Yeong;Moon Seong-Hyeok
    • Journal of Korean Port Research
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    • v.2 no.1
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    • pp.7-28
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    • 1988
  • From the viewpoint of physical distribution, the port transport process can be regarded as a system which consists of various subsystems such as navigational aids, quay handling, transfer, storage, information If management, and co-ordination with inland transport. The handling productivity of this system is determined by the production level of the least productive subsystem. So, a productivity analysis on the flow of cargoes through each subsystem should be made in order to achieve efficient port operation. The purpose of this paper is to analyze the productivity of each subsystem in Pusan port, and to bring forward problems and finally to draw up plans for their betterment. Analyzed results on the productivity of each subsystem are as follows, i) It is known that the number of tugs with low HP should be increased by a few, the number of tugs with medium HP is appropriate, and the number of tugs with high HP is in excess of that necessary. ii ) In the case of container cargoes, it is found that the transfer and storage systems in BCTOC have the lowest handling capability, with a rate of $115\%$, leading to bottle-necks in the port transport system, while the handling rate of the storage and quay handling systems in general piers is in excess of the inherent capability. iii) In the case of the principal seaborne cargoes passing through general piers, there is found to be a remarkable bottle-neck in the storage system. In the light of these findings, both the extension of storage capability and the extension of handling productivity are urgently required to meet the needs of port users. Therefore, iv) As a short-term plan, it is proposed that many measures such as the reduction of free time, the efficient application of ODCY, etc must be brought in and v) In the long-trun, even though the handling capability will accommodate an additional 960,000 TEU in 1991, the scheduled completion date of the third development plan of Pusan port, insufficiency of handling facilities in the container terminal is still expected and concrete countermeasures will ultimately have to be taken for the port's harmonious operation. In particular, the problem of co-ordination with inland transport and urban traffic should be seriously examined together in the establishment of the Pusan port development. As a method of solving this, vi) It is suggested that Pusan port (North port) should be converted into an exclusive container ternimal and overall distribution systems to the other ports for treating general cargoes must be established. vii) And finally, it is also proposed that the arrival time (cut-off time) of influx cargoes for exports such as general merchandise and steel product should be limited, with a view to securing cargoes suitable for the operational capability of BCTOC.

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