• Title/Summary/Keyword: position analysis

Search Result 7,348, Processing Time 0.039 seconds

Reliability of implant stability measuring devices depending on various clinical conditions: an in vitro study

  • Han-Na Lee;Myoung-Sub Kim;Jeong-Yol Lee;Xu Zihan;Jae-Jun Ryu;Ji-Suk Shim
    • The Journal of Advanced Prosthodontics
    • /
    • v.15 no.3
    • /
    • pp.126-135
    • /
    • 2023
  • PURPOSE. The aim of this study was to evaluate the reliability of implant stability measuring devices depending on the location of the implant and the position of the patient. MATERIALS AND METHODS. Six implants were installed in different dentate sextants of six artificial bone models. Implant stability was measured in three conditions of the bone model (without mounting on a phantom head, mounted on a phantom head in supine position, and mounted on a phantom head in upright position). A resonance frequency analysis device (Osstell) and two damping capacity analysis devices (Periotest and Anycheck) were used to measure implant stability. The values measured outside the phantom head were treated as controls, and the values inside the phantom head were compared using an independent t-test. RESULTS. Osstell showed different results in two of the six divisions in both the supine and upright positions compared to outside of the mouth (P < .05). Periotest showed different results in all six parts in the supine position and in five parts in the upright position compared to outside of the mouth (P < .05). While Anycheck showed different results in five areas in the supine position compared to outside of the mouth, it showed different results in only one area in the upright position (P < .05). CONCLUSION. In the difficult implant position for the operator to access, the implant stability measuring devices show less reliability. The accessibility of implant is greatly affected in the order of Osstell, Anycheck, and Periotest.

An analysis of ITI implants placed in korean patients (한국환자에 매식된 ITI 임플란트에 관한 조사)

  • Chang, Moon-Taek
    • Journal of Periodontal and Implant Science
    • /
    • v.32 no.2
    • /
    • pp.361-370
    • /
    • 2002
  • The aim of this study was to analyze various data of 120 non-submerged ITI implants placed in 64 korean adults. The data were retrieved from patients' charts and registered in the computer and coded for a statistical analysis. The results revealed that the most common type of edentulism was a distal extension case, and the largest number of implants were placed in the mandibular first molar position. Implants were placed more frequently in mandibular, posterior position than maxillary, anterior position, respectively. With respect to the implant diameter and length, an implant with 4.1mm in diameter and more than 10mm in length was the most common. Since a molar position was the most prevalent position for implant placement in korean patients, clinicians should be careful about implant diameter which can resist a strong occlusal force expected in the molar position. In addition, the distance to the mandibular canal and the floor of maxillary sinus should be considered to avoid possible damages, such as nerve injury and sinus perforation in selecting a proper implant length.

Analysis and a Compensation Method for Torque Ripple caused by Position Sensor Error in PMSM's Vector Control (PMSM의 벡터제어시 위치센서 오차에 의해 발생하는 토오크 리플에 대한 해석과 그 보상 방법)

  • Lee, J.M.;Mok, H.S.;Choe, G.H.;Kim, S.H.;Cho, Y.H.
    • Proceedings of the KIPE Conference
    • /
    • 2007.07a
    • /
    • pp.205-207
    • /
    • 2007
  • Position information is very important when driving the Permanent Magnet Synchronous Motor(PMSM). Generally, resolver is used to obtain exact position information. However, it generates periodic position errors due to the transformer ratio difference and excitation signal distortion. When the vector control is done with the position information that includes position error, torque ripple is periodically generated. This paper proposes the solution through analysis of above problem. Also, it’s validity is verified by simulation and experiment.

  • PDF

A Study on the Application to Network Analysis on the Importance of Author Keyword based on the Position of Keyword (학술논문의 저자키워드 출현순서에 따른 저자키워드 중요도 측정을 위한 네트워크 분석방법의 적용에 관한 연구)

  • Kwon, Sun-Young
    • Journal of the Korean Society for information Management
    • /
    • v.31 no.2
    • /
    • pp.121-142
    • /
    • 2014
  • This study aims to investigate the importance of author keyword with analysis the position of author keyword in journal. In the first stage, an analysis was carried out on the position of author keyword. We examined the importance of author keyword by using degree centrality, closeness centrality, betweenness centrality, eigenvector centrality and effective size of structural hole. In the next stage, We performed analysis on correlation between network centrality measures and the position of author keyword. The result of correlation analysis on network centrality measures and the position of author keyword shows that there are the more significant areas of the result of the correlation analysis on degree centrality, betweenness centrality and the position of keyword. In addition, These results show that we need to consider that the possible way as measuring the importance of author keyword in journal is not only a term frequency but also degree centrality and betweenness centrality.

A COG Variable Analysis of Air-rolling-breakfall in Judo (유도 공중회전낙법의 COG변인 분석)

  • Kim, Eui-Hwan;Chung, Chae-Wook;Kim, Sung-Sup
    • Korean Journal of Applied Biomechanics
    • /
    • v.15 no.3
    • /
    • pp.117-132
    • /
    • 2005
  • It was to study a following research of "A Kinematic Analysis of Air-rolling-breakfall in Judo". The purpose of this study was to analyze the Center of Gravity(COG) variables when performing Air-rolling-breakfall motion, while passing forward over(PFO) to the vertical-hurdles(2m height, take off board 1m height) in judo. Subjects were four males of Y. University squad, who were trainees of the demonstration exhibition team, representatives of national level judoists and were filmed by four 5-VHS 16mm video cameras(60field/sec.) through the three dimensional film analysis methods.COG variable were anterior-posterior directional COG and linear velocity of COG, vertical directional COG and linear velocity of COG. The data collections of this study were digitized by KWON3D program computed The data were standardized using cubic spline interpolation based by calculating the mean values and the standard deviation calculated for each variables. When performing the Air-rolling-breakfall, from the data analysis and discussions, the conclusions were as follows : 1. Anterior-posterior directional COG(APD-COG) when performing Air-rolling-breakfall motion, while PFO over to the vertical-hurdles(2m height) in judo. The range of APD-COG by forward was $0.31{\sim}0.41m$ in take-off position(event 1), $1.20{\sim}1.33m$ in the air-top position(event 2), $2.12{\sim}2.30m$ in the touch-down position(event 3), gradually and $2.14{\sim}2.32m$ in safety breakfall position(event 4), respectively. 2 The linear velocity of APD-COG was $1.03{\sim}2.14m/sec$. in take-off position(event 1), $1.97{\sim}2.22m/sec$. gradually in the air-top position(event 2), $1.05{\sim}1.32m/sec$. in the touch-down position (event 3), gradual decrease and $0.91{\sim}1.23m/sec$. in the safety breakfall position(event 4), respectively. 3. The vertical directional COG(VD-COG) when performing Air-rolling-breakfall motion, while PFO to the vertical-hurdles(2m height) in judo. The range of VD-COG toward upward from mat was $1.35{\sim}1.46m$ in take-off position(event 1), the highest $2.07{\sim}2.23m$ in the air-top position(event 2), and after rapid decrease $0.3{\sim}0.58m$ in the touch-down position(event 3), gradual decrease $0.22{\sim}0.50m$ in safety breakfall position(event 4), respectively. 4. The linear velocity of VlJ.COG was $1.60{\sim}1.87m/sec$. in take-off position(event 1), $0.03{\sim}0.08m/sec$. gradually in the air-top position(event 2), $-4.37{\sim}\;-4.76m/sec$. gradual decrease in the touch-down position(event 3), gradual decrease and -4.40${\sim}\;-4.77m/sec$. in safety breakfall position(event 4), respectively. When performing Air-rolling-breakfall showed parabolic movement from take-off position to air-top position, and after showed vertical fall movement from air-top position to safety breakfall. In conclusion, Ukemi(breakfall) is safety fall method Therefore, actions need for performing safety fall movement, that decrease and minimize shock and impact during Air-rolling-breakfall from take-off board action to air-top position must be maximize of angular momentum, and after must be minimize in touch-down position and safety breakfall position.

Optimization of feed system of base mold for washing machine using CAE (사출성형 CAE를 이용한 세탁기용 Base 성형용 금형의 유동 시스템 최적화)

  • Yoo, Min-ji;Kim, Kyung-A;Han, Seong-Ryeol
    • Design & Manufacturing
    • /
    • v.15 no.1
    • /
    • pp.1-7
    • /
    • 2021
  • The position of the gate is one of the important factors for optimal injection molding. This is because inappropriate gate positions cannot fill the cavity uniformly, which can lead to defects such as contraction. In this study, CAE was performed on hot runner injection molding of the washing machine base and plasticity was compared by changing gate position from existing gate position. A total of two alternatives have been applied to compare the plasticity of the washing machine base according to its optimal gate position. The gate position of the improved molds and the gate position of the current mold is analyzed by injection molding analysis. The results of the fill time, the pressure at V/P switchover, clamping force, and deflection were compared. In washing machine base injection molding, the deflection was reduced by about 3.76% in the improved mold 2. In improved mold 1, the fill time during injection molding was reduced by 3.32% to enable uniform charging, and the clamping force was reduced by 31.24%. We have confirmed that the position of the gate can change the charging pressure and the clamping force and affect the quality and cost savings of the molded product.

Optimization Analysis of the Shape and Position of a Submerged Breakwater for Improving Floating Body Stability

  • Sanghwan Heo;Weoncheol Koo;MooHyun Kim
    • Journal of Ocean Engineering and Technology
    • /
    • v.38 no.2
    • /
    • pp.53-63
    • /
    • 2024
  • Submerged breakwaters can be installed underneath floating structures to reduce the external wave loads acting on the structure. The objective of this study was to establish an optimization analysis framework to determine the corresponding shape and position of the submerged breakwater that can minimize or maximize the external forces acting on the floating structure. A two-dimensional frequency-domain boundary element method (FD-BEM) based on the linear potential theory was developed to perform the hydrodynamic analysis. A metaheuristic algorithm, the advanced particle swarm optimization, was newly coupled to the FD-BEM to perform the optimization analysis. The optimization analysis process was performed by calling FD-BEM for each generation, performing a numerical analysis of the design variables of each particle, and updating the design variables using the collected results. The results of the optimization analysis showed that the height of the submerged breakwater has a significant effect on the surface piercing body and that there is a specific area and position with an optimal value. In this study, the optimal values of the shape and position of a single submerged breakwater were determined and analyzed so that the external force acting on a surface piercing body was minimum or maximum.

Effect of Kegel Exercise on Vital Capacity According to the Position: A Preliminary Study

  • Park, KangHui;Park, HanKyu
    • The Journal of Korean Physical Therapy
    • /
    • v.32 no.4
    • /
    • pp.217-221
    • /
    • 2020
  • Purpose: This study examined the immediate effect of Kegel exercise on the vital capacity according to the position. Methods: Seventeen subjects participated in the study (male=7, female=10). The subjects performed Kegel exercise in two positions: sitting and hooklying. The order of exercise was conducted in a random order selected by the subjects to exclude the learning effect. The maximum voluntary ventilation (MVV) was measured using a spirometer. The vital capacity was measured according to the manual in the sitting position before the experiment. After each exercise, the vital capacity was also measured in the same way. One way repeated measures analysis of the variance (ANOVA) was used to compare the vital capacity according to the position, and a Bonferroni test was used for post hoc analysis. Results: Significant differences in vital capacity were observed after exercise than before exercise (p<0.05). Post-hoc analysis, however, revealed no difference in vital capacity according to the position (p>0.05). Conclusion: This study was a preliminary study to determine the vital capacity according to the Kegel exercise and two positions. Nevertheless, further study with several revisions of the number of subjects, duration, and time for intervention will be needed.

Socio-cultural position of women in Nepal and Korea: A comparative approach

  • Gadtaulaa, Swechchha;Chung, Yong Kyo
    • Journal of Contemporary Eastern Asia
    • /
    • v.15 no.2
    • /
    • pp.162-176
    • /
    • 2016
  • In this study, a part of the social and the economic condition of Nepali women is introduced with a short comparison to the socio-cultural position of the women of Korea. A relative definition of the condition of the past and now: this also briefly introduces the ideas of some of the Nepali women that we have collected through the questionnaire. A comparative literature reviews about the position of women in the past as well as the review of the position of women in present is made. Various articles are used for this as the method of analysis. A quantitative analysis of the status of women (Nepal) taking 24 households through the questionnaire method was done. The answers given by the women are the base for the article. However, the answers to the questionnaire are used to compare the past and the present. Analysis of the received data and their explanation through the tables and graph are done. The charts and tables are followed by a detailed explanation. Conclusively the briefing of the condition of women in both the countries, the changes that are brought or not brought by development; in their life's status and position in society, is mentioned.

Correlation analysis of radiation therapy position and dose factors for left breast cancer (좌측 유방암의 방사선치료 자세와 선량인자의 상관관계 분석)

  • Jeon, Jaewan;Park, Cheolwoo;Hong, Jongsu;Jin, Seongjin;Kang, Junghun
    • The Journal of Korean Society for Radiation Therapy
    • /
    • v.29 no.1
    • /
    • pp.37-48
    • /
    • 2017
  • Purpose: The most basic conditions of radiation therapy is to prevent unnecessary exposure of normal tissue. The risk factors that are important o evaluate the dose emitted to the lung and heart from radiation therapy for breast cancer. Therefore, comparing the dose factors of a normal tissue according to the radion treatment position and Seeking an effective radiation treatment for breast cancer through the analysis of the correlation relationship. Materials and Methods: Computed tomography was conducted among 30 patients with left breast cancer in supine and prone position. Eclipse Treatment Planning System (Ver.11) was established by computerized treatment planning. Using the DVH compared the incident dose to normal tissue by position. Based on the result, Using the SPSS (ver.18) analyzed the dose in each normal tissue factors and Through the correlation analysis between variables, independent sample test examined the association. Finally The HI, CI value were compared Using the MIRADA RTx (ver. ad 1.6) in the supine, prone position Results: The results of computerized treatment planning of breast cancer in the supine position were V20, $16.5{\pm}2.6%$ and V30, $13.8{\pm}2.2%$ and Mean dose, $779.1{\pm}135.9cGy$ (absolute value). In the prone position it showed in the order $3.1{\pm}2.2%$, $1.8{\pm}1.7%$, $241.4{\pm}138.3cGy$. The prone position showed overall a lower dose. The average radiation dose 537.7 cGy less was exposured. In the case of heart, it showed that V30, $8.1{\pm}2.6%$ and $5.1{\pm}2.5%$, Mean dose, $594.9{\pm}225.3$ and $408{\pm}183.6cGy$ in the order supine, prone position. Results of statistical analysis, Cronbach's Alpha value of reliability analysis index is 0.563. The results of the correlation analysis between variables, position and dose factors of lung is about 0.89 or more, Which means a high correlation. For the heart, on the other hand it is less correlated to V30 (0.488), mean dose (0.418). Finally The results of independent samples t-test, position and dose factors of lung and heart were significantly higher in both the confidence level of 99 %. Conclusion: Radiation therapy is currently being developed state-of-the-art linear accelerator and a variety of treatment plan technology. The basic premise of the development think normal tissue protection around PTV. Of course, if you treat a breast cancer patient is in the prone position it take a lot of time and reproducibility of set-up problems. Nevertheless, As shown in the experiment results it is possible to reduce the dose to enter the lungs and the heart from the prone position. In conclusion, if a sufficient treatment time in the prone position and place correct confirmation will be more effective when the radiation treatment to patient.

  • PDF