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Revisit Intention of Visitors to Cultural Festival using Logit Model (로짓모형을 이용한 축제참가자의 재방문 의사 분석)

  • Heo, Chung-Uk
    • Korean Business Review
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    • v.22 no.1
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    • pp.139-156
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    • 2009
  • This article investigates the relationships between motivation and revisit intention of visitors to Gangneung Danoje Festival as cultural festival with social demand. Out of 550 questionnaires distributed, a total of 514 usable questionnaires were collected. The hypothesized causal model was tested by logit model, which included satisfaction model to each program as well as overall satisfaction model to cultural festival. Model 1 is constructed with satisfaction and revisit intention to each program, and Model 2 with overall satisfaction and revisit intention to cultural festival. In this models causal variables were inputted including satisfaction to festival programs, frequency of visitation, days of stay, time required to destination. In Model 1 positive sign were shown by causal variables as satisfaction to each program, frequency of visitation, days of stay but negative signs was shown by time required to festival place. In Model 2 sign directions of causal variables were same in Model 1. In comparison, Model 2 is more significant than Model 1 on the basis of statistical theory as significance level and coefficient of determination. Consequently, cultural festival managers should test the satisfaction level of visitors to each program of cultural festival and make efforts to establish advanced program in order to attract more visitors.

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A top-down forecasting model for analyzing the export market of information and telecommunication products (정보통신기기 수출 예측을 위한 하향식(Top-down) 모형에 관한 연구)

  • 지형구;주영진;김찬규;이영호;김영휘
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2000.04a
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    • pp.318-321
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    • 2000
  • 이 연구는 정보통신기기 수출량에 관해 하향식(Top-down) 방법에 기초한 예측 모형을 제시한다. 하향식방법은 전체 수출량과 전체를 구성하는 개별 항목간에 계층적 관계를 바탕으로 순차적으로 예측을 수행하는 방법이다. 전체와 개별 항목간에 관계는 데이터의 시계열 특성과 데이터에 영향을 주는 요인들에 의해서 만들어진다. 이러한 관계를 바탕으로 하는 하향식 예측은 전체 수출량을 먼저 예측한 후 이 예측치를 바탕으로 하여 개별 항목에 대한 예측을 수행한다. 하지만 하향식 방법은 가장 아래 계층의 예측치를 산출하기 위해 필요한 것이며 최종 예측치는 가장 마지막 계층에서부터 예측 데이터를 합산해서 얻을 수 있다. 결국 하향식 예측 방법은 전체와 개별 항목 사이에 상관관계가 높고 계층화되어 있는 구조에 적합하다. 이 예측 대상이 되는 정보통신기기 수출량에 대한 적용 사례를 살펴보자. 계층 구조를 보면 정보통신기기 전체 수출량과 전체를 구성하는 개별 항목으로 정보통신기기 분류별(유선기기, 무선기기, 방송기기, 정보기기, 기타부품기기)과 국가별(미국, 일본, 중국 등 7 개국)로 나뉘어진다. 다시 이 아래 계층으로는 국가와 정보통신기기의 행렬 구조(예: 미국-유선, 일본-부품 등)에 의해 35 개로 나뉘어진다. 각 단계별 예측 방법을 보면 전체 수출량은 시계열 특성과 거시적 변수를 반영한 시계열 모형, 그 아래 계층인 국가별과 분류별 모형에는 전체 수출량 시계열 특성과 국가별과 분류별에 영향을 주는 관련 변수를 반영한 회귀모형 그리고 행렬 구조에 대한 예측은 상위 계층의 시계열 특성과 행렬구조 데이터의 계절성이 반영된 다중 회귀모형을 이용하였다.ndex, mobile user′s will first be classified by their traffic volume, and then calculate the average tariffs per minute of each group of users, and lastly weight-average those tariffs per minute. And finally, this paper shows the mobile tariff index by considering those averaged tariffs and the carriers′ market shares to reflect the contribution of individual carriers and the users′ traffic volume.완화될 수 있다. 즉, 봉지를 씌웅으로서 봉지 내의 대기 환경이 외기보다 안정적으로 유지되고 직사광선이나 농약 및 마찰로부터 과실을 보호해 주기에 동녹이 어느 정도 방지될 수 있는 것이다. 그러나 기존의 황금배봉지는 동녹의 정도를 완화시킬 뿐 완전히 방지할 수 없었으며, 봉지를 적 용한 재배조건에서의 동녹발생 기구를 정확히 이해하지 못했었기에 효과적으로 봉지의 기능 을 개선하는 것이 불가능하였다. 과설의 미려도는 과실의 맛과 함께 그 가치를 결정짓는 중요한 물성으로서 우리나라 황 금배 재배환경과 특성에 알맞은 배봉지의 제작이 선결될 때, 배 품질의 향상, 안정된 공급이 가능하게 될 것이며 아울러 농가의 수업증대와 수출 경쟁력 강화가 이루어질 수 있을 것으로 판단된다. 이러한 측면에서 황금배 재배농가가 당면한 동녹발생의 문제점을 신속한 해결 을

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Reliability Analysis of the Gravity Retaing Wall (중력식(重力式) 옹벽(擁壁)의 신뢰도(信賴度)에 관한 연구(研究))

  • Paik, Young Shik;Lee, Yong Il
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.3 no.2
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    • pp.127-135
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    • 1983
  • A new approach is developed to analyze the reliability of the earth retaining wall using the concept of probability of failure, instead of conventional factor of safety. Many uncertainties, which are included in the conventional stability analysis, can be excluded by using the stochastic approach. And the reliability, more consistent with the reality, can be obtained by the simulation. The strength parameters of soil properties are assumed to be random variables to follow a generalized beta distribution. The interval [A, B] of the random variables could be determined using the maximum likelihood estimation. The pseudo-random values corresponding to the proposed beta distribution are generated using the rejection method. The probability of failure defined as follows, is obtained by using the Monte Carlo Method. $$P_f=\frac{M}{N}$$ where, $P_f$ : Probability of failure N : Total number of trials M : Total number of failure out of N A computer program is developed for the computation procedure mentioned above. Finally, a numerical example is solved using the developed program.

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An Experimental Study on Behavior Characteristics of the Pretension Soil Nailing Systems (프리텐션 쏘일네일링 시스템의 거동특성에 관한 실험적 고찰)

  • Choi, Young-Geun;Shin, Bang-Woong;Park, Si-Sam;Kim, Hong-Taek
    • Journal of the Korean Geotechnical Society
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    • v.20 no.2
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    • pp.87-96
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    • 2004
  • Application of the soil nailing method is continuously extending in maintaining stable excavations and slopes. However, ground anchor support system occasionally may not be used because of space limitations in urban excavation sites nearby the existing structures. In this case, soil nailing system with relatively short length of nails could be efficiently adopted as an alternative method. The general soil nailing support system, however, may result in excessive deformations particularly in an excavation zone of the existing weak subsoils. Pretensioning the soil nails then could play important roles to reduce deformations mainly in an upper part of the nailed-soil excavation system as well as to improve local stability. In this study, a newly modified soil nailing technology named as the PSN (Pretension Soil Nailing) is developed to reduce both facing displacements and ground surface settlements in top-down excavation process as well as to increase the global stability. Up to now, the PSN system has been investigated mainly focusing on an establishment of the design procedure. In the present study, laboratory model tests are carried out to investigate the failure mechanism and behavior characteristics of the PSN system. Various results of model tests are also analyzed to provide a fundamental basis for the efficient design.

An Analytical Study on the Slope Safety Factor Considering Various Conditions (다양한 조건을 고려한 사면안전율에 관한 해석적 연구)

  • Park, Choon-Sik;Ahn, Sang-Jin
    • Journal of the Korean Geotechnical Society
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    • v.35 no.5
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    • pp.31-41
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    • 2019
  • This paper demonstrates safety factor for effective planning at initial stage by utilizing results on changes of safety factor according to various conditions of slop and examines impacts of factors that affect slope safety factors as well. Firstly, it describes shear strength which satisfies minimum allowable safety factor: 1.20 depending on height and slope. As the height increases by 5.0 m, the safety factors decrease by 0.04 while it tends to consistently reduce by approximately 20%, 30% and 40% after height goes to 10.0 m. As slope reduces by about 0.3, the safety factors increases by 0.4, which shows the rate of safety factors on slope grows by about 10%, 20% and 30% on lowering slope. When cohesion goes up by 10.0 kPa the safety factors increases by around 40% respectably while the angle of internal friction grows by $5^{\circ}$, it increases by about 8%. The rate of safety factors is identified as $Fs=3.86H^{-0.59}$, Fs = 0.43 s, Fs = 0.04 c, $Fs=0.02{\phi}$ depending on height, slope and shear strength. The safety factor with rainfall infiltration tends to increase by 18% compared to the condition of saturated surface on earth.

Enhancement of combustion efficiency of a air-cooled combustor system with single F.D. Fan Using CFD (전산유체역학을 이용한 단일 송풍기가 적용된 공냉식 연소설비의 효율개선)

  • Kim, Min-Choul;Shon, Byung-Hyun;Lee, Jae-Jeong;Park, Hung-Suck
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.6
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    • pp.460-468
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    • 2021
  • This study investigated the enhanced combustion efficiency of an "air-cooled combustion system" with single F.D. fan, and performed a numerical analysis for the operation and design conditions to increase the combustion efficiency. The combustion efficiency in an actual combustor was compared before and after the structure modification. Numerical analysis for application of a single fan revealed the difficulty of forming a turbulence for circular combustion conditions. This is because the supply ratio of combustion air supplied into 2 flow paths becomes irregular in the combustion furnace due to a change in friction force and pressure in each flow path. Subsequently, two methods of supplying air into the combustion furnace were analyzed numerically to obtain the optimal combustion conditions of an air-cooled combustion system. The first method involved injecting the preheated combustion air after a 180~360 degree rotation from the outer wall, whereas in the second method, the combustion air was injected into the combustion furnace in a tangential direction after primary heat exchange outside the combustion furnace, by applying a rotatable vane structure in the combustion furnace. Results reveal that application of a single F.D. fan to the air injection into a rotatable combustion furnace is desirable for optimization of the combustion conditions for applying a duct structure having a dual cooling wall for the cooling of the outer wall of the combustion furnace, and for maintaining perfect mixing in the combustion furnace. We therefore confirmed enhanced combustion efficiency by comparing the actual combustion efficiency before and after structure modification.

Analysis on the Rainfall Triggered Slope Failure with a Variation of Soil Layer Thickness: Flume Tests (강우로 인한 조립토 사면에서의 토층 두께 변화에 따른 사면의 활동 분석: 실내 모형실험)

  • SaGong, Myung;Yoo, Jea-Ho;Lee, Sung-Jin
    • Journal of the Korean Geotechnical Society
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    • v.25 no.4
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    • pp.91-103
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    • 2009
  • Slope failure depends upon the climatic features related to related rainfall, structural geology and geomorphological features as well as the variation of the mechanical behaviors of soil constituting a slope. In this paper, among many variables, effects of soil layer thickness on the slope failure process, and variations of matric suction and volumetric water content were observed. When the soil layer is relatively thick, the descending wetting front decreases matric suction and the observed matric suction reaches to "0" value. When the wetting front reaches to the impermeable boundary, the bottom surface of steel soil box, ascending wetting front was observed. This observation can be postulated to be the effects of various sizes of pores. When macro size pores exist, the capillary effects can be reduced and infilling of pore will be limited. The partially filled pores would be filled with water during the ascending of the wetting front, which bounces from the impermeable boundary. This assumption has been assured from the observation of variation of the volumetric water contents at different depth. When the soil layer is thick (thickness = 20 cm), for granular material, erosion is a cause triggering the slope failure. It has been found that the initiation of erosion occurs when the top soil is fully saturated. Meanwhile, when the soil layer is shallow (thickness = 10 cm), slope slides as en mass. The slope failure for this condition occurs when the wetting front reaches to the interface between the soil layer and steel soil box. As the wetting front approaches to the bottom of soil layer, reduction of shear resistance along the boundary and increase of the unit weight due to the infiltration occur and these produce complex effects on the slope failure processes.

Cases and Legal Issues For 119paramedics in Mental Emergency Situations (정신응급상황에서 119구급대원 대응사례와 법적쟁점)

  • Young Pyo Hong
    • The Korean Society of Law and Medicine
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    • v.25 no.1
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    • pp.87-115
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    • 2024
  • In Korea, exposure to stress has been accompanied by mental pain in the process of achieving many growth along with rapid development, various social problems, and the frequency of emergency hospitalization is increasing.. In the case of mentally ill patients, "unwanted hospitalization" is a problem, and police and 119 paramedics try to suppress the body of mentally ill patients, and many problems are exposed This is because the constituent requirements of the provisions of emergency hospitalization under the Mental Health and Welfare Act do not reflect reality, and each institution has a different position on one mentally ill person, and emergency hospitalization does not proceed smoothly or leads to friction between related organizations, and the safety of the mentally ill or others is not secured. Emergency hospitalization is defined as "a person who finds a person who is presumed to be mentally ill and is at high risk of harming his or her health or safety or others," and if the situation is so urgent that he or she cannot afford time to go through the hospitalization procedure to decide on his or her own hospitalization, he or she can request emergency hospitalization with the consent of a doctor and a police officer. In this case, 119 paramedics are escorted to a psychiatric institution. This provision of emergency hospitalization poses many problems in the process of transferring to psychiatric institutions. If a police officer or 119 paramedics in charge of practice use "physical force" during the emergency hospitalization process, side effects will inevitably occur, and professional negligence can be a problem. Specifically, when exercising physical force, the minimum necessary physical restraint based on laws and regulations and proportional principles is required, and the lack of the duty of care of 119 paramedics or police officers under the laws and regulations will eventually be resolved by applying other laws and regulations. Accordingly, it will be an opportunity for mentally ill patients to be transferred to psychiatric institutions in a safe environment by changing the subject of emergency hospitalization provisions under the Mental Health Welfare Act, defining and prescribing the use of physical protection guards as the enforcement regulations of the Mental Health Act, setting the duty of care for 119 paramedics and police officers, and creating an environment for transportation so that mentally ill patients can be treated safely.

Three-dimensional finite element analysis of initial tooth displacement according to force application point during maxillary six anterior teeth retraction using skeletal anchorage (골격성 고정원을 이용한 상악 6전치 후방 견인시 힘의 적용점 변화에 따른 치아 이동 양상에 관한 유한 요소법적 분석)

  • Kim, Chan-Nyeon;Sung, Jae-Hyun;Kyung, Hee-Moon
    • The korean journal of orthodontics
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    • v.33 no.5 s.100
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    • pp.339-350
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    • 2003
  • The purpose of this study was to investigate the micro-implant height and anterior hook height to prevent maxillary six anterior teeth from lingual tipping and extruding during space closure. We manufactured maxillary dental arch form, bracket and wire, using the computer aided three-dimensional finite element method. Bracket was $.022'{\times}.028'$ slot size and attached to tooth surface. Wire was $.019'{\times}.025'$ stainless steel and $.032'{\times}.032'$ stainless steel hook was attached to wire between lateral incisor and canine. Length of hook was 8mm and force application points were marked at intervals of In. Four micro-implants were implanted on alveolar bone between second premolar and first molar. The heights of them were 4, 6, 8, 10mm starting from wire. We analyzed initial displacement of teeth by various force application point applying force of 150gm to each micro-implant and anterior hook. The conclusions of 4his study are as the following : 1. When the micro-implant height was 4m and the anterior hook height was 5mm and below, anterior teeth were tipped lingually. When the anterior hook height was 6mm and above, anterior teeth were tipped labially. 2. When the micro-implant height was 6mm and the anterior hook height was 6mm and below, the anterior teeth were tipped lingually. When the anterior hook height was 6m and above, the anterior teeth were tipped labially. But lingual tipping of anterior teeth decreased and labial tipping Increased when the micro-implant height was 6mm, compared with 4mm micro-implant height. 3. When the micro-implant height was 8mm and the anterior hook height was 2mm, the anterior teeth were tipped lingually. When the anterior hook height was 3mm and above, labial tipping movement of the anterior teeth increased proportionally. 4. When the micro-implant height was 10mm and the anterior hook height was 2mm and above, labial tipping of the anterior teeth increased proportionally. 5. As the anterior hook height increased, aterior teeth were tipped more labially. But extrusion occurred on canine and premolar area because of the increase of wire distortion. 6. Movement of the posterior teeth was tipped distally during maxillary six anterior teeth retraction using micro-im plant because of the friction between bracket and were Based on the results of this study, we could predict the pattern of the tooth movement according to position of micro-implant and height of anterior hook. It seems that we can find the force application point for proper tooth movement in consideration of inclination of anterior anterior teeth, periodontal condition, overjet and overbite