• Title/Summary/Keyword: 견인력

Search Result 261, Processing Time 0.032 seconds

A Action Research on Team-Based Learning Problem Solving Activity (팀 기반 학습 문제해결 활동에 대한 실행 연구)

  • Yu, Jae-Young
    • 대한공업교육학회지
    • /
    • v.42 no.1
    • /
    • pp.87-105
    • /
    • 2017
  • The purpose of this study was to verify that students' interest in team activities for problem solving, the effect of interest on it, and students' changes in perceptions and their behavioral characteristics in the process of problem solving. The study reviewed documents prepared by students, such as work sheets, descriptive questionnaires, works and their photos, student activity photos and observation journals of teachers. The results of this research are as below. First, a problem solving team activity for making a model car was considered an interesting assignment by more than 90% of male/female students. The fact that female students could be more focused on this assignment than male students was discovered. Interest in the assignment not only had an influence on the points from the start (the blueprint) to the end (model cars completed based upon the designs) of problem solving, but also provided the traction power behind the assignment. Second, the problem solving team activity allowed the students to change their existing recognition (thoughts) while positively taking a lead or indirectly utilizing various learning experiences (including experiences of failure). Third, $2^{nd}$ graders in middle school had a tendency to solve problems in dependently rather than to receive help from others when they encountered problematic situations.

AN EXPERIMENTAL STUDY ON THE EFFECT OF THE MANDIBULAR RETRACTIVE FORCE ON THE MANDIBULAR CONDYLE OF GROWING YOUNG DOG (하악 후방 견인력이 성장기 유견의 하악과두에 미치는 영향에 관한 실험적 연구)

  • Lim, Yong-Kyu;Yang, Won-Sik
    • The korean journal of orthodontics
    • /
    • v.20 no.2
    • /
    • pp.363-379
    • /
    • 1990
  • The purpose of this study was to evaluate the effects of the mandibular retractive force on the mandibular condyle of growing dog. The experimental animals were six mongrel dogs of two-month old. Their deciduous dentition were completed. Two of them was used as control group, and experimental group was composed of remaining four. Head band and chin cup were made of cotton tape, and hooks are fabricated on the chin cup and had band for closed coil. Mandibular retractive force was 100g/side and chin cap appliance was used for 14 hours/day during night. Experimental group were sacrificed at 2, 4, 6, 8 weeks from beginning of the experiment. Right TMJ was prepared for histologic study and left TMJ was examined grossly for disc, fossa, and condyle. The conclusions are: 1. Two-month old control animal showed active cartilaginous growth on the mandibular condyle, therefore showed thick proliferative and hypertrophic zones. Remodeling process in the condyle head was observed in which there were bone resorption on the anterior surface and bone apposition on the posterior surface. 2. Four-month old control animal showed marked reduction of hypertrophic zone but the condylar bone remodeling was more pronounced. 3. In experimental group, there are marked reduction of hypertrophic zone at 4 weeks from beginning of experiment, and hypertrophic zone disappeared at posterior-superior portion of condyle in 6-week experimental animal. 8 week experimental animal showed slight recovery of hypertrophic zone. 4. In experimental group, bone deposition was increased at anterior surface of condyle, and bone resorption was increased at posterior surface of condyle. 5. In control group, the glenoid fossa and surrounding bone showed mainly bone apposition. But experimental group showed bone resorption at anterior surface of articular eminence and increased bone apposition at posterior surface of postglenoid spine. 6. No marked traumatic change was seen but 4 weeks and 8 weeks experimental animal showed flattening of posterior surperior condylar surface. Bone marrow of condyle showed minute focal bleeding in 2 weeks and 4 weeks experimental animal, and congestion and depression of hematopoietic bone marrow during all experimental period.

  • PDF

The design and construction with the JES method used steel elements for under pass in korea and the practical use of the JES method (강재 엘리먼트를 이용한 기계식 UNDER PASS 공법(JES 공법)의 국내 적용 사례 및 활용 방안 연구)

  • Jeong, Gyeong-Hwan;Jung, Sun-Tae;Kim, Do-Hyeong;Kim, Jung-Sung;Hwang, Young-Chul;Park, Min-Kwan
    • Proceedings of the KSR Conference
    • /
    • 2009.05a
    • /
    • pp.1498-1508
    • /
    • 2009
  • Recently, the expansion of roads are necessary because the population and vehicles have rapidly increased, but those are restricted because of the limited site. JES(Jointed Element Structure) method is the method of the new cross-structure, which is element-traction method which draws and excavates elements under the existing structure with high accuracy within a short time. Also JES(Jointed Element Structure) method has a facility of the economical execution, a small effect on the train-service during construction period and no limit of the crossing length under the trade In this study, the tractive force and settlement are compared with the upper element, side wall element and the lower element respectively in the section which the JES method is applied In the case of element located at left side wall, the tractive force measured by a guage is double or more than the tractive force calculated by a formula. It is expected that many boulder contented in the ground contrary to the site investigation data cause high tractive force. For comparison of the settlement, the settlement as excavating the upper element is the largest in all steps. It is expected that this is the same as the cause of high tractive force. Also in this study, the practical use of the JES method when some under pass structures are extended in the future is studied.

  • PDF

THE CARE OF DELAYED MALUNION AFTER MAXILLARY FRACTURE BY DIFFERENT METHODS:REPORT OF THREE CASES (치료법을 달리한 상악골절후 부정유합 2예)

  • Yoo, Jae-Ha;Lee, Won-Yoo;Rew, Soo-Jang
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.13 no.1
    • /
    • pp.117-127
    • /
    • 1991
  • When open reduction of maxilla fractures is postponed due to concurrent life-threatening injuries, delayed union may result with malunion or nonunion. If delayed malunion is occurred, significant facial deformity may result, including a dished-out face, irregular retromaxillism with Angle's class III malocclusion, open anterior bite, nasal collapse, telecanthus and malar flattening. The treatment planning for this problem includes cephalometric evaluation anterior and lateral tomograms, dental casts, orthodontic planning, dental planning and use of impression tray to rupture the fibrous tissue casts, orthodontic planning, dental planning and use of impression tray to rupture the fibrous tissue attachment at the fracture site. In this paper, one case presented a 58-year-old female patient with maxilla retrusion after comminuted fracture, who was treated with orthodontic methods of maxillary protraction headgear and Plaster headcap, whereas the other two cases were about male patients who were treated principally with surgically open reduction or Le Fort I-controlled transverse osteotomy with iliac bone graft.

  • PDF

A Generalized Model for the Prediction of Thermally-Induced CANDU Fuel Element Bowing (CANDU 핵연료봉의 열적 휨 모형 및 예측)

  • Suk, H.C.;Sim, K-S.;Park, J.H.
    • Nuclear Engineering and Technology
    • /
    • v.27 no.6
    • /
    • pp.811-824
    • /
    • 1995
  • The CANDU element bowing is attributed to actions of both the thermally induced bending moments and the bending moment due to hydraulic drag and mechanical loads, where the bowing is defined as the lateral deflection of an element from the axial centerline. This paper consider only the thermally-induced bending moments which are generated both within the sheath and the fuel and sheath by an asymmetric temperature distribution with respect to the axis of an element The generalized and explicit analytical formula for the thermally-induced bending is presented in con-sideration of 1) bending of an empty tube treated by neglecting the fuel/sheath mechanical interaction and 2) fuel/sheath interaction due to the pellet and sheath temperature variations, where in each case the temperature asymmetries in sheath are modelled to be caused by the combined effects of (i) non-uniform coolant temperature due to imperfect coolant mixing, (ii) variable sheath/coolant heat transfer coefficient, (iii) asymmetric heat generation due to neutron flux gradients across an element and so as to inclusively cover the uniform temperature distributions within the fuel and sheath with respect to the axial centerline. As the results of the sensitivity calculations of the element bowing with the variations of the parameters in the formula, it is found that the element bowing is greatly affected relatively with the variations or changes of element length, sheath inside diameter, average coolant temperature and its variation factor, pellet/sheath mechanical interaction factor, neutron flux depression factor, pellet thermal expansion coefficient, pellet/sheath heat transfer coefficient in comparison with those of other parameters such as sheath thickness, film heat transfer coefficient, sheath thermal expansion coefficient and sheath and pellet thermal conductivities.

  • PDF

Size and Retention of Tongue Bulb for Tongue Retaining Device (혀 유지구의 크기와 유지력 평가)

  • Park, Nam-Seon;Lee, Ki-Ho;Kim, Mee-Eun;Kim, Ki-Suk
    • Journal of Oral Medicine and Pain
    • /
    • v.32 no.3
    • /
    • pp.283-292
    • /
    • 2007
  • In several treatment modalities for snoring and obstructive sleep apnea (OSA), oral appliances mainly including mandibular advancement appliance (MAA) and tongue retaining device (TRD) are recognized as a non-invasive, reversible alternative with favorable results. Tongue bulb is a major component of TRD which prevents the tongue from approaching the posterior wall of the pharynx and can be combined with MAA. Determination of tongue bulb size for the patient is important for therapeutic effect, but frequently needs time-consuming work. For effective fabrication and standardization of tongue bulbs, this study aimed to categorize tongue bulb size for healthy young men and to examine its relation with maximum retention force and with physical parameters including tongue-related variables. 36 non-snoring, asymptomatic young men with normal occlusion were voluntarily participated in this study (mean age: $24.47{\pm}2.58$ years). Experimental procedures consisted of prefabrication of tongue bulb set (20 types with a width of 27-36mm and thickness of 8 and 10 mm), determination of tongue bulb size and the maximum retention force for each subject, and measurement of physical parameters including body mass index (BMI), neck circumference and width, thickness and length of tongue. This study showed that there was significant difference of retention force among the bulb size-related groups both in upright and supine position (p<0.05) and that retention force increased with bulb size. Correlation of tongue bulb size with physical parameters was not clearly verified and there was no significant difference in retention force between upright and supine positions. Based on our results, it can be suggested that retention force relates with tongue bulb size, ultimately with tongue volume. A further study needs to be performed in the patients with snoring and OSA.

Case Study on the Leadership Shifts in Smart Phone Industry: Rise of China and Falling Behind of Korea (스마트폰 산업에서의 주도권 이전: 중국의 부상과 우리나라의 쇠퇴에 관한 사례 연구)

  • Kwak, Kiho;Lee, Eunju
    • Journal of Technology Innovation
    • /
    • v.26 no.2
    • /
    • pp.95-128
    • /
    • 2018
  • Since mid and late 2000s, the smartphones has been widely diffused and Korea ranked first in global smartphone market in 2011 thanks to its rapid adoption of Android operating system, technology capability accumulated in featurephone development, vertical integration on smartphone production and premium positioning. However, Korea fell behind because of the rise of another latecomer, China, in four years (2015) after it recorded the top position globally. How did the leadership change occurred in the smartphone industry so rapidly? In order to answer the question, we investigated three favorable windows of opportunity for the rise of China, which are technological, demand, and institutional, and the strategic responses of Chinese firms as well as the rigidity and complacency with the past success of Korean firms. Our findings contribute to the extension of 'catch-up cycle' theory as well as provide in-depth insights for strategies and policies settings to overcome the recent rise of China in information and communication technology sector for Korea.

A Study on the Development of the Tourism Information Service based on a Service Science - Focus on Using VWORLD - (서비스 사이언스에 기반을 둔 관광정보 서비스 개발에 관한 연구 - VWORLD 활용을 중심으로 -)

  • Oh, Myung Woo;Kim, Hyung June;Koh, Junehwan
    • Spatial Information Research
    • /
    • v.21 no.1
    • /
    • pp.23-36
    • /
    • 2013
  • Recently, the VWORLD was built to ensure competition on the advance of domestic enterprise into foreign markets with rapid expansion of spatial information industry of the world. However, the policy to secure user is insufficient because the VWORLD's service is embryonic stages. Then again, tourist industry is growing rapidly and leading the world economy and number of domestic tourists are also steadily increasing. Although the size was expanded, Korean tourist industry's competition is relatively weak, so some scholars insist that raising the tourist industry's quality. This backgrounds make a study of the tourism information service. So, this paper progressed a study on the development of the tourism information service based on a service science and used VWORLD as a test model. This paper drew the customer's demands on the tourism information service and strategic points of the development from those by using a Quality Function of Deployment of service science's new service development methodologies. After that this study prioritized those strategic points. As a result, 'Face Map' that is a service model was made. Moreover, this study have try to raise the development's effectiveness and efficiency based on service science's a new service development process.

Study on the competitiveness enhancing strategy of Korean service trade through FTA - Focus on the logistics industry - (FTA를 활용한 서비스무역 경쟁력 제고방안 연구 - 물류산업을 중심으로 -)

  • Sohn, Sungpyo
    • International Commerce and Information Review
    • /
    • v.18 no.2
    • /
    • pp.151-167
    • /
    • 2016
  • This study is focus on the relationship between the role of FTA and service trade performance enhancing strategy in Korea. and It is on the verification of the focus to the competitive promoting strategy of the logistics industry. finally proposition of the policy making to the government is proposed in the research. The invigoration of the service trade through FTA focus on the logistics industry is very combinative economy policy target with the side of government and the side of private enterprises both. added to this, this is the goal of impossible to achieve just with the development of logistics industry itself. it needs to construct the organic relationship, that is the implement and enforcement of the SCM through logistics industry network. Thus, on logistics, the 3rd party operating system implementation is top priority to gain international competitiveness. furthermore, the 4th party facilitation including consulting function and IT technology to pursue the maximum effectiveness logistics service providing.

  • PDF

A Study on the Influence of Characteristics of Service Nature Dynamic Capability on Organizational Innovation of Small and Medium size Manufacturing Firms (서비스 본질 특성과 동태적 역량이 중소제조기업의 조직혁신에 미치는 영향)

  • Lee, JeungSun;Kim, Hyunsoo
    • Journal of Service Research and Studies
    • /
    • v.8 no.1
    • /
    • pp.27-39
    • /
    • 2018
  • This study is an empirical study to examine the effect of the characteristics of service nature of Korean small and medium manufacturing firms on organizational innovation. It is essential to know service in order for Korea, which has a strong image as a fast follower, to enhance the competitiveness of Small and Medium size Manufacturing firms. By analyzing the service characteristics phenomenon, it is possible to understand the service nature characteristics and to strengthen the capacity to meet them. In order to gain a new resource while achieving organizational innovation, the manufacturing industry can produce new demand for the main products with competitive advantage. The characteristics of service nature are derived from relationship, equality, interactivity, and experiential value. In order to enhance the competitiveness of small and medium size manufacturing firms, core competencies required for organizational innovation are set as dynamic competencies, and to prove it. The dynamic capacity was found to affect the relationship, interactivity, and experience value. It is proved that it is an important factor to promote organizational innovation as a capability to identify and actively utilize organizational innovation opportunities ahead of competitors in a rapidly changing environment. It is needed to confirm that large corporations, midsize companies, and overseas companies can achieve the same results.