• Title/Summary/Keyword: Body Segment

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A Musculoskeletal Model of a Human Lower Extremity and Estimation of Muscle Forces while Rising from a Seated Position (인체 하지부 근골격계 모델 및 의자에서 일어서는 동작 시 근력 예측)

  • Jo, Young-Nam;Yoo, Hong-Hee
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.22 no.6
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    • pp.502-508
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    • 2012
  • An analytical model for a human body is important to predict muscle and joint forces. Because it is difficult to estimate muscle or joint forces from a human body, the objective of this study is the development of a reliable analytical model for a human body to evaluate the lower extremity muscle and joint forces. The musculoskeletal system of the human lower extremity is modeled as a multibody system employing the Hill-type muscle model. Muscle forces are determined to minimize energy consumption, and we assume that motion is constrained in the sagittal plane. Muscle forces are calculated through an equilibrium analysis while rising from a seated position. The musculoskeletal model consists of four segments. Each segment is a rigid body and connected by frictionless revolute joints. Muscles of the lower extremity are simplified to seven muscles with those that are not related to the sagittal plane motion are ignored. Muscles that play a similar role are combined together. The results of the present study are compared with experimental results to validate the lower extremity model and the assumptions of the present study.

A multisource image fusion method for multimodal pig-body feature detection

  • Zhong, Zhen;Wang, Minjuan;Gao, Wanlin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.11
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    • pp.4395-4412
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    • 2020
  • The multisource image fusion has become an active topic in the last few years owing to its higher segmentation rate. To enhance the accuracy of multimodal pig-body feature segmentation, a multisource image fusion method was employed. Nevertheless, the conventional multisource image fusion methods can not extract superior contrast and abundant details of fused image. To superior segment shape feature and detect temperature feature, a new multisource image fusion method was presented and entitled as NSST-GF-IPCNN. Firstly, the multisource images were resolved into a range of multiscale and multidirectional subbands by Nonsubsampled Shearlet Transform (NSST). Then, to superior describe fine-scale texture and edge information, even-symmetrical Gabor filter and Improved Pulse Coupled Neural Network (IPCNN) were used to fuse low and high-frequency subbands, respectively. Next, the fused coefficients were reconstructed into a fusion image using inverse NSST. Finally, the shape feature was extracted using automatic threshold algorithm and optimized using morphological operation. Nevertheless, the highest temperature of pig-body was gained in view of segmentation results. Experiments revealed that the presented fusion algorithm was able to realize 2.102-4.066% higher average accuracy rate than the traditional algorithms and also enhanced efficiency.

A NUMERICAL SIMULATION METHOD FOR FREE SURFACE FLOWS NEAR MOVING BODIES IN A FIXED RECTANGULAR GRID SYSTEM (고정된 직사각형 격자계에서 움직이는 물체주위 자유수면유동 계산을 위한 수치기법의 개발)

  • Jeong, K.L.;Lee, Y.G.;Ha, Y.J.
    • 한국전산유체공학회:학술대회논문집
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    • 2011.05a
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    • pp.395-406
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    • 2011
  • In this research a numerical simulation method is developed for moving body in free surface flows using fixed staggered rectangular grid system. The non-linear free surface near the body is defined by marker-density method. The body boundary is defined by line segment connecting the points where the body surface and grid line meet. Continuity equation and Navier-Stokes equations are used as governing equations and the equations are coupled with two-step projection method. The velocities and pressures of body boundary and free surface cells are calculated with simultaneous iterative method. To treat a body movement in a fixed grid system, the volume displaced by moving body is added to the divergence of the body boundary cell. For the verification of the present numerical method. vortex shedding period of advancing cylinder is calculated and the period is compared with existing experiment results. Moreover, added mass and damping coefficients of a vertically excited box are calculated and the computed results are compared with published experiment results. Impulsive pressure and water level variation due to sloshing phenomenon are simulated and the results are compared with published experiment results. Varying the plunger shape, the waves generated by plunging type wave maker are compared with the 2nd order Stokes wave theory The plunger shape generating the wave that shows the best agreement with the theory is represented.

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Eine Structure of the Pineal Body of the Snapping Turtle (자라 송과체의 미세구조)

  • Choi, Jae-Kwon;Oh, Chang-Seok;Seol, Dong-Eun;Park, Sung-Sik;Cho, Young-Kook
    • Applied Microscopy
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    • v.25 no.2
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    • pp.39-52
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    • 1995
  • Pinealocytes in the lower vertebrate are known to have photoreceptive function. These photoreceptor cells have been characterized morphologically in various species of lower vertebrates. No such ultrastructural studies, however, were reported in fresh water turtle. The purpose of this study is to characterize the pinealocytes and the phylogenetic evoluton of these cells is discussed in terms of functional analogy. I. Light microscopy: The pineal body was divided into incomplete lobules by connective tissue septa containing blood vessels, and parenchymal cells were arranged as irregular cords or follicular pattern. In the lobules, glandular lumina were present and contained often densely stained materials. II. Electron microscopy: The pineal parenchyma had three categories of cells: photoreceptor cells, supportive cells and nerve cells. The photoreceptor cells had darker cytoplasm compared to the supportive cells, and the enlarged apical cytoplasm(inner segment) containing abundant mitochondria and dense cored vescles protruded into the glandular lumen in which lamellar membrane stacks(outer segment), dense membranous materials, and cilia were present. Some of these lamellated membrane stacks appeared to be dege-nerating while others were apparently newly formed. Constricted neck portion of the photoreceptor cells contained longitudinally arranged abundant microtubules. centrioles and cross-striated rootlets. Cell body had well developed Golgi apparatus, abundant mitochondria, dense granules($0.5{\sim}1{\mu}m$), dense cored vesicles($70{\sim}100nm$), and rough endoplasmic reticulum occasionally with dense material within its cisterna. Basal portion of the photoreceptor cells had basal processes often with synaptic ribbons, which terminate in the complicated zone of cellular and neuronal processes. Synatpic ribbons often made contact with the nerve processes and the cell processes of neighboring cells. In some instances, these ribbons were noted free within the basal process and were also present at the basal cell mem-brane facing the basal lamina. Obvious nerve endings with clear and dense cored vesicles were observed among the parenchymal cells. Photoreceptor cells of the snapping turtle pineal body were generally similar in fine structure to those of other lower verterbrates reported previously, and suggested to have both photoreceptive and secretory functions which were modulated by pinealofugal and pinealopedal nerves. The supportive cells were characterized by having large dense granules($0.3{\sim}1{\mu}m$), abundant ribosomes, well developed Golgi apparatus and rough endoplasmic reticulum. These cells were furnished with microvilli on the luminal cell surfaces, and often had centrioles, striated rootlets, abundant filaments especially around the nucleus, and scattered microtubules. Some supportive cells had cell body close to the lumen and extended a long process reaching to basal lamina, which appeared to be a glial cell. Nerve cells within the parenchyma were difficult to identify, but some large cells located basally were suspected to be nerve cells, since they had synaptic ribbon contact with photoreceptor cells.

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FERTILITY STUDY (SEGMENT 1) OF RECOMBINANT GRANULOCYTE-MACROPHAGE COLONY STIMULATING FACTORS (LBD-005) IN RATS

  • Kim, Sung-Hoon;Chung, Moon-Koo;Roh, Jung-Koo
    • Toxicological Research
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    • v.8 no.1
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    • pp.29-40
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    • 1992
  • The recombinant glycoprotein, LBD-005 (Lucky R & D Center, Biotechnology)stimulates the growth of stem cells and activates the development of the hematopoietic cell in a similar manner to the naturally occurring GM-CSF. This test was conducted to investigate if LBD-005 had any effect on fertility in male and female rats. Sprague-Dawley rats(88 of each sex) bred at KRICT, were dosed subcutaneously, at a volume of 2ml/kg body weight with LBD-005 at 0, 250, 500 or 1, 000mg/kg body weight. The male rats were dosed, from 6 weeks of asge, for 60 days prior to mating.

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Static Walking Algorithm for a Quadruped Robot using Tilting (틸팅을 이용한 4족 보행 로봇의 정적 보행 알고리즘)

  • Lee, Sun-Geol;Jo, Chang-Hyeon;Kim, Byeong-Su
    • Journal of Institute of Control, Robotics and Systems
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    • v.7 no.8
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    • pp.675-679
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    • 2001
  • This paper presents walking algorithm for a quadruped robot that does not have an upper body. Tilting motion is added to the planned walking trajectory instead of using an extra body segment that is independent on walking trajectory. Area and tracking algorithms are proposed as tilting method and compared with that of off-line tilting and that of no tilting. Computer simulation shows that stability of tilted walking is more improved than that of the usual walking algorithm for general walking paths. It also shows that the tracking method guarantees stability and best mobility.

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The effects of vertebroplasty on adjacent vertebra (척추성형술이 인접 척추체에 미치는 영향)

  • Park, Jung-Soo;Choi, Chul-Hyun;Chae, Soo-Won
    • Proceedings of the KSME Conference
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    • 2007.05a
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    • pp.746-750
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    • 2007
  • Vertebroplasty has drawn much attention as a medical treatment for the compression fracture of spine, which strengthens the vertebral body and corrects deformity, and relieves pain in patients by injecting bone cement. However vertebroplasty can cause fracture on adjacent vertebra due to relative stiffness change. This study involves the biomechanical evaluation of the vertebroplasty especially on adjacent vertebral body. The finite element method has been employed to analyze the patient who was treated vertebroplasty under static and dynamic loading. For this study, a three-dimentioal model of the three-level ligamentous lumbar segment ($L1{\sim}L3$)is created from medical image data (CT)and compared with the experimental results in vitro.

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The Characteristic Improvements of One-Coil Coin Type Vibration Motor (One-Coil Coin Type Motor의 특성 개선)

  • Kwak, Dong-Soo;Kim, Sang-Gil;Shin, Heung-Kyo;Kweon, Chang-Myoung
    • Proceedings of the KIEE Conference
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    • 2000.11b
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    • pp.327-329
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    • 2000
  • This paper present the characteristic improvements of one-coil coin type vibration Motor. Rotor is consist of coreless coil and 4 segment commutator. Magnet is 4 pole, z direction magnetized. This one-coil coin type vibration motor has simple mechanical structure and good efficiency. So production cost is lower than other having 2 or more coils coin type motor but it has the weak points. That is small vibration magnitude and dead zone. Modifying the shape of rotor, vibration magnitude is increased. To avoid the dead zone we attached more magnetic body on rotor. As result we show the optimal position of magnetic body.

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Ontogenetic variation in Chironomus flaviplumus (Diptera, Chironomidae) larvae

  • Hyunsu Yoo;Jae-won Park;Ihn-Sil Kwak
    • Journal of Species Research
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    • v.13 no.1
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    • pp.41-49
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    • 2024
  • Chironomus is a large genus of Diptera comprising about 400 species and occurs worldwide except for Antarctica. The strong morphological cross-taxon similarity of chironomid larvae renders identification at the species level difficult. Here, we analyzed the morphology of larvae of Chironomus flaviplumus, an easily cultured species employed as a bioindicator in polluted environments, to determine identifying morphological characteristics at the first through fourth instar. Observed differences appearing at each instar include the presence or absence of setae on the body and tubules on the 10th and 11th body segment, the number of seta interna in the mandible, and the presence or absence of ring organs in the antennae. Some specific morphological characteristics did not change after hatching. Our findings provide a reliable method for identifying C. flaviplumus larvae.

Effects of Low Frequency Electro-Acupuncture (ST36) on the Adjuvant-Induced Arthritis in Rats (저빈도(低頻度) 족삼리(足三里) 전함랄극(電緘剌戟)이 흰쥐의 Adjuvant 유발(誘發) 관절염(關節炎)에 미치는 영향(影響))

  • Kim, Jong-Chul;Lee, Eun-Yong;Seo, Il-Beok;Koo, Sung-Tae;Choi, Sung-Mi;Kim, Ee-Hwa
    • Journal of Acupuncture Research
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    • v.23 no.6
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    • pp.207-219
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    • 2006
  • Objectives : This study was to investigate the effect of low frequency electro-acupuncture (EA) at ST36 acupoint on the Freund's Complete Adjuvant(FCA)-induced arthritis in rats. Methods : Arthritis was induced by intradermal injection of FCA into base of tail. Experimental groups were divided into 4 groups; Normal, Control, ST36 and Non-Acupoint(NA). ST36 group was treated by 2 Hz EA at ST36 acupoint. Body weight, paw edema volun1e and ankle joint thickness were measured after treatment. And we investigated the effects of 2 Hz EA via WBC count, segment neurophil, lymphocyte, PGE2 assay and NADPH-d histochemistry. Results and Conclusion : The mean of body weight and ankle joint thickness of ST36 group was increased compared with control group. The mean of paw edema volume, WBC count, segment neutrophil and lymphocyte of were not decreased with control group. The mean of PGE2 concentration and NADPH-d positive neurons were changed significantly compared with control group.

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