• Title/Summary/Keyword: A level-set method

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The Study of Joint Motion and Friction on the Floor of Poly Urethane for the Cutting Movement of Various Angles (폴리우레탄 바닥재에서 방향 전환 각도에 따른 하지 관절의 움직임과 마찰력에 관한 연구)

  • Moon, Gon-Sung;Choi, Ji-Young
    • Korean Journal of Applied Biomechanics
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    • v.25 no.3
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    • pp.363-370
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    • 2015
  • Objective : The purpose of this study was to give the basic data for the cutting movement with the various angels on the poly urethane. Method : Ten healthy men voluntarily participated in this study. A three-dimensional motion analysis system (VICON) and force plates were used to analyze the movements of the joints for the lower extremities. For the statistical analysis the IBM SPSS 21.0 was used to perform repeated measured ANOVA and post-hoc comparison result was used to perform the Scheffe and the level of significance was set up at ${\alpha}=.05$. Results : There were significant differences for the time required for the increasing angles of the cutting movement(p<.05). In addition, there were significant differences for the maximum dorsiflexion, plantarflexion of ankle joint, maximum flexion of knee joint and hip joint with the increasing the angles of cutting movement(p<.05). Also, there were significant differences for the maximum adduction and abduction angle of the hip joint with the increasing of the angles of cutting movement. There was signigicant difference for the resultant utilized coefficient of friction(RuCOF) for the increasing angles of cutting movement(p<.05). Conclusion : There was a pattern to increase the coefficient friction with the angle of cutting direction. Also, it would be possible to use the poly urethane for the outdoor floor with the results of this study.

Relationship between Leisure Activities, Job Satisfaction and Quality of Life among Security Agents (시큐리티 요원의 여가활동과 직무만족 및 삶의 질의 관계)

  • Kim, Kyong-Sik;Lee, Kwang-Lyeol;Kim, Pyung-Su;Kim, Chan-Sun
    • The Journal of the Korea Contents Association
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    • v.9 no.3
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    • pp.336-344
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    • 2009
  • This study is to examine the relationship between leisure activities, job satisfaction and quality of life among security agents. To attain the goal of the study described above paragraphs, private guards held in Seoul and Gyeong-Gi were set as a collected group. Then, using judgment sampling method, finally drewout and analyzed 333 peoples in total. The result of reliability analysis check up was here below; Chronbach's $\alpha$= .665-.816. The conclusion drawn from this study is as follows: First, it make no difference between leisure types in job satisfaction. Second, there is a difference between leisure type in quality of life. Third, the level of leisure activities results in the indirect, direct effect on quality of life through job satisfaction. Job satisfaction is an important variable intermediating the relationship between leisure activiteis and quality of life.

An Experimental Study on the Analysis of the Interventricular Pressure Waveform in the Moving-Actuator type Total Artificial Heart (이동작동기식 완전 이식형 인공 심장의 심실간 공간 압력 파형 해석에 관한 실험적 연구)

  • 조영호;최원우
    • Journal of Biomedical Engineering Research
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    • v.18 no.1
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    • pp.25-36
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    • 1997
  • To regulate cardiac output of the Total Artificial Heart(TAH) physiologically, the hemodynamic information must be toed back to the controller. So far, our group has developed an automatic cardiac output control algorithm using the motor current waveform, It is, however difficult to detect the preload level such as a filling status of ventricular inflow and the variation of atrial pressures within normal physiologic range(0-15 mmHg) by analyzing the motor current which simultaneously reflects the afterload effect. On the other hin4 the interventricular volume pressure(IVP) which is not influenced by arterload but by preload is a good information source for the estimation of preload states. In order to find the relationship between preload and IVP waveform, we set up the artificial heart system on the Donovan type mock circulatory system and measured the IVP waveform, right and left atrial pressures, inflow and outflow waveforms and the signals represented the information of moving actuator's position. We shows the feasibility of estimating the hemodynamic changes of inflow by using IVP waveform. fife found that the negative peak value of IVP waveform is linearly related to atrial pressures. And we also found that we could use the time to reach the negative peak in IVP waveform, the time to open outflow valve, the area enclosed IVP waveform as unfu parameters to estimate blood filling volume of diastole ventricle. The suggested method has advantages of avoiding thrombogenesis, bacterial niche formation and increasing longterm reliability of sensor by avoiding direct contact to blood.

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Ab Initio Conformational Study on Ac-Pro-$NMe_2$: a Model of Polyproline

  • Kang, Young-Kee
    • Proceedings of the Korean Biophysical Society Conference
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    • 2003.06a
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    • pp.75-75
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    • 2003
  • We report here the results on N-acetyl-N'-dimethylamide of proline (Ac-Pro-NM $e_2$) calculated using the ab initio molecular orbital method with the self-consistent reaction field (SCRF) theory at the HF level with the 6-31+G(d) basis set to investigate the conformational preference of polyproline depending on the cis/trans peptide bonds and down/up puckerings along the backbone torsion angle $\square$ in the gas phase, chloroform, and water. In the gas phase, Ac-Pro-NM $e_2$ has seven local minima of tFd, tFu, cFd, cFu, cAu, tAu, and cAd conformations. In particular, polyproline conformations tFd, tFu, cFd, and cFu are found to be more stable than $\square$-helical conformations cAu, tAu, and cAd. In contrast, Ac-Pro-NHMe has seven local minima of tCd, tCu, cBd, cAu, tAu, cFd, and cFu conformations. Conformations tCd and tCu are found to be most stable, which is ascribed to the intramolecular hydrogen bond between C=O of acetyl group and $N^{~}$ H of N'-methyl amide group. The stability of the cFd conformation (i.e., the polyproline I structure) in chloroform is somewhat increased, relative to that in water, although tFd and tFu conformations (i.e., the polyproline II structure) are dominate both in chloroform and water. The population of backbone conformations feasible in chloroform and water is consistent with the experiments. This work is supported by a Korea Research Foundation Grant (KRF-2002-041-C00129).

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Fusion algorithm for Integrated Face and Gait Identification (얼굴과 발걸음을 결합한 인식)

  • Nizami, Imran Fareed;An, Sung-Je;Hong, Sung-Jun;Lee, Hee-Sung;Kim, Eun-Tai;Park, Mig-Non
    • Journal of the Korean Institute of Intelligent Systems
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    • v.18 no.1
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    • pp.72-77
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    • 2008
  • Identification of humans from multiple view points is an important task for surveillance and security purposes. For optimal performance the system should use the maximum information available from sensors. Multimodal biometric systems are capable of utilizing more than one physiological or behavioral characteristic for enrollment, verification, or identification. Since gait alone is not yet established as a very distinctive feature, this paper presents an approach to fuse face and gait for identification. In this paper we will use the single camera case i.e both the face and gait recognition is done using the same set of images captured by a single camera. The aim of this paper is to improve the performance of the system by utilizing the maximum amount of information available in the images. Fusion in considered at decision level. The proposed algorithm is tested on the NLPR database.

Synthesis, Crystal Structure and Quantum Chemistry of a Novel Schiff Base N-(2,4-Dinitro-phenyl)-N'-(1-phenyl-ethylidene)-hydrazine

  • Ji, Ning-Ning;Shi, Zhi-Qiang;Zhao, Ren-Gao;Zheng, Ze-Bao;Li, Zhi-Feng
    • Bulletin of the Korean Chemical Society
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    • v.31 no.4
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    • pp.881-886
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    • 2010
  • A novel Schiff base N-(2,4-dinitro-phenyl)-N'-(1-phenyl-ethylidene)-hydrazine has been synthesized and structurally characterized by X-ray single crystal diffraction, elemental analysis, IR spectra and UV-vis spectrum. The crystal belongs to monoclinic with space group P21/n. The molecules are connected via intermolecular O-$H{\cdots}O$ hydrogen bonds into 1D infinite chains. The crystal structure is consolidated by the intramolecular N-$H{\cdots}O$ hydrogen bonds. weak intermolecular C-$H{\cdots}O$ hydrogen bonds link the molecules into intriguing 3D framework. Furthermore, Density functional theory (DFT) calculations of the structure, stabilities, orbital energies, composition characteristics of some frontier molecular orbitals and Mulliken charge distributions of the title compound were performed by means of Gaussian 03W package and taking B3LYP/6-31G(d) basis set. The time-dependent DFT calculations have been employed to calculate the electronic spectrum of the title compound, and the UV-vis spectra has been discussed on this basis. The results show that DFT method at B3LYP/6-31G(d) level can well reproduce the structure of the title compound.

Study on How the Height of the Table Influences of the Functional Ability Perfomence to Patients Group with Stroke (뇌졸중 환자군을 대상으로 한 작업대 높이가 수행도에 미치는 영향에 대한 연구)

  • Yu, Young-Yul;Kim, Hee-Soo
    • Journal of the Ergonomics Society of Korea
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    • v.28 no.4
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    • pp.9-15
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    • 2009
  • Our study goal is to find out how the table height influences functional ability of upper extremity to patients with stroke when they are having therapy. In this study, we tested forty patients with stroke at the age of over sixty-five who do not have visual, auditory disability and have no difficulty in communicating and moving things by using upper extremity. And they were able to pinch grip in hospital. We used occupational table for occupational therapy as Lab Materials. We also used cube and pegs board to test upper extremity functional ability. We used occupational table for occupational therapy as Lab Materials and we used cube and pegs board to test upper extremity functional ability. The method is that we measured the recommended table height that takes the subjects' size into consideration and patients' preferred table height and therapists' preferred table height and we applied them and then we have done a comparative analysis and set significance level(p<0.05). As the result, we found the Statistically significant between the recommended height and the other two, which are patients' preferred height and therapists' preferred height. We also discovered that functional ability of upper extremity varies significantly depending on each table height. We came to a conclusion that the table height had effects on the upper extremity functional ability of patients with stroke who are over sixty-five years old. It is therefore considered that the proper table height is important to improve upper extremity functional ability of patients with stroke for their physical therapy.

THE INFLUENCE OF THE INITIAL STABILITY AFTER DENTAL IMPLANT INSTALLATION ON THE OSSEOINTEGRATION (임프란트 식립시 초기 안정성이 골유착에 미치는 영향)

  • Lee, Young-Hoon;Kim, Yeo-Gab;Choi, Byung-Jun
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.30 no.6
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    • pp.518-528
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    • 2008
  • Purpose: The long-term experience of using osseointegrated implants for prosthetic rehabilitation of the edentulous patients shows that high success rates can be predictably achieved. Primary implant stability has been identified to be a prerequisite to achieve osseointegration. In this study, we set up the amount of removed bone so that it differed on implant installation site for each group. The influence of each initial stability on secondary stability and osseointegration was compared with time lapse using resonance frequency analysis and histomorphometric analysis. Materials and methods: A total 27 US $II^{(R)}$ (Osstem, Korea) implants were placed in the mandibular edentulous area of 3 beagle dogs. The implant site was prepared by the conventional technique with drills, and three experimental groups were divided into under-drilling group, normal-drilling group and over-drilling group. The Implant Stability Quotient (ISQ) was measured at intervals of immediately, 4, 8, 12 weeks after placement using $Osstell^{(R)}$ mentor RFA. After the animals were sacrificed, histomorphometric evaluation was executed for measuring BIC and BD. Results: 1) The under-drilled group showed most high ISQ value for whole experiment period. 2) Bone-to-implant-contact(BIC) showed the tendency to be increased gradually as the experiment period passed except the 8 weeks of the normal group. 3) The under-drilled group showed most high bone density(BD) level for whole experiment period, and it was expressed the aspect to be increased gradually according to an experiment period passage in the average of all group. 4) Resonance frequency analysis and histomorphometric analysis are presumed by generally proportional. Conclusions: As this research result, it seems that there are some correlation between resonance frequency analysis and histomorphometric analysis. As are accomplished osseointegration stably so that more superior at the region which the overpressure comes to add, it will be applicable method in clinical field.

The Effects of Bridge Exercise with Contraction of Hip Adductor Muscles on Thickness of Abdominal Muscles (고관절 내전근 수축을 이용한 교각운동이 복부근육의 두께에 미치는 영향)

  • Lee, Geon-Cheol;Bae, Won-Sik;Kim, Chi-Hyok
    • Journal of the Korean Society of Physical Medicine
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    • v.9 no.2
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    • pp.233-242
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    • 2014
  • PURPOSE: The purpose of this study was to determine the correlation between the hip adductor muscles and abdominal muscles during bridge exercise. METHOD: Participants who met the criteria for this study(n=36) were divided into the three groups. The first experimental group performed normal bridge exercises and the second group performed bridge exercises with the contraction of the hip adductor muscles and the control group didn't perform any exercise. Transversus abdominis muscle thickness was measured by ultrasound imaging with a special transducer head device, at pre exercise, after 2 weeks, 4 weeks, and 6 weeks. RESULT: Data were analyzed using repeated ANOVA with the level of significance set at ${\alpha}=.05$. Transversus abdominis muscle thickness was influenced by contraction of the hip adductor muscles during bridge exercise in people without lower back pain. Compared with normal bridge exercise, transversus abdominis muscle thickness significantly increased in thickness during bridge exercise with contraction of the hip adductor muscles(p<.05). CONCLUSION: The results from this study showed that contraction of the hip adductor muscles during bridge exercise increased change in the transversus abdominis muscle thickness. These results can be a good source to prevent low back pain due to hip adductor weakness. Therefore, inducing activation of hip adductor with abdominal stabilizing exercise is more effective in patients with low back pain.

Basic Study on Monitoring System of Reservoir and Leeve Using Wireless Sensor Network (무선센서 네트워크 계측을 이용한 저수지 및 제방 계측시스템 구축에 관한 기초연구)

  • Yoo, Chanho;Kim, IkHoon;Lee, Seungjoo;Hwang, Jungsoon;Baek, Seungcheol
    • Journal of the Korean GEO-environmental Society
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    • v.19 no.1
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    • pp.25-30
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    • 2018
  • Conventional monitoring method is used for evaluation of the reservoir and levee at the highest height sections. In recent years, automated measurement technology has been developed, and the measurement results are transmitted, collected and stored in real time into management office. Despite the development of real time monitoring technology, the measurement results are not used directly or indirectly with facility management at real time. Recently, as wireless sensor network measurement technology has been developed based on internet of things, this study proposed a real - time measurement and evaluation system based on wireless sensor network technology in the reservoir structure. As a result of the seepage analysis for the application, it was confirmed that the volumetric water content changes together with the change of the seepage line inside the embankment body according to the change of the water level of the embankment. In other words, the applicability of the measurement system with the volumetric water ratio set as the sensor node was verified.