• Title/Summary/Keyword: Knee point

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Many-objective Evolutionary Algorithm with Knee point-based Reference Vector Adaptive Adjustment Strategy

  • Zhu, Zhuanghua
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.16 no.9
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    • pp.2976-2990
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    • 2022
  • The adaptive adjustment of reference or weight vectors in decomposition-based methods has been a hot research topic in the evolutionary community over the past few years. Although various methods have been proposed regarding this issue, most of them aim to diversify solutions in the objective space to cover the true Pareto fronts as much as possible. Different from them, this paper proposes a knee point-based reference vector adaptive adjustment strategy to concurrently balance the convergence and diversity. To be specific, the knee point-based reference vector adaptive adjustment strategy firstly utilizes knee points to construct the adaptive reference vectors. After that, a new fitness function is defined mathematically. Then, this paper further designs a many-objective evolutionary algorithm with knee point-based reference vector adaptive adjustment strategy, where the mating operation and environmental selection are designed accordingly. The proposed method is extensively tested on the WFG test suite with 8, 10 and 12 objectives and MPDMP with state-of-the-art optimizers. Extensive experimental results demonstrate the superiority of the proposed method over state-of-the-art optimizers and the practicability of the proposed method in tackling practical many-objective optimization problems.

Illuminance Dynamic Range Expansion using Gamma & Multi-Point Knee for Smart Phone Camera (감마 및 다중 포인터 니를 이용한 스마트폰 카메라의 광 다이나믹 영역 확장)

  • Choi, Duk-Kyu;Han, Chan-Ho
    • IEMEK Journal of Embedded Systems and Applications
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    • v.8 no.1
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    • pp.43-50
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    • 2013
  • The narrow dynamic range of most smart phone cameras is severely limited. It usually is narrower than the dynamic range of most scenes. So we proposes a illuminance dynamic range expansion using multi-point knee for smart phone camera. Such as logarithmic functions the proposed method compress the image sensor output signal. Additionally, the proposed method was merged into the gamma that is essential circuit for any cameras. To justifying multi-point knee effectiveness, we configure the control and quality evaluation system for smart phone camera module. Experimental results show that the lost information by cut off and saturated affectively reconstructed in darker and in brighter areas. Finally this methods have advantage to implement without any changing hardware for conventional smart phones.

Clothing Pressure and Subjective Sensations in Slacks using the Cutting Lines of the Knee Parts (슬랙스의 무릎절개선 활용에 따른 의복압 및 착용감)

  • Lee, Joung-Suk;Sung, Su-Kwang
    • Fashion & Textile Research Journal
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    • v.6 no.1
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    • pp.109-113
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    • 2004
  • The present study attempted to consider the effects of cutting lines in the knee parts of slacks on the clothing pressure and comfort. The study compared and analyzed the pressure imposed to the body in a stooping position and the consequent sensations felt by the wearer according to the slack shapes. The conclusion was drawn as follows: The pressure imposed by the slacks to the body is greater on the two points slightly upper and lower from the knee point than on the knee point itself, regardless of the slack shapes. Clothing pressure was lower in the slacks with 10 cm-wide and 14 cm-wide cutting lines in the knee parts than those with 18 cm-wide cutting lines. Subjective sensations felt in the knee parts were analyzed according to slacks shapes. As a result, it was found that slacks without cutting lines on the knee parts or with sewing lines far from the knee points were more comfortable. In slacks construction, the use of cutting lines in the knee parts can decrease pressure imposed to the knee area or improve the comfort of the slacks. When designing slacks, however, overall appearance should be considered and the weakness of cutting line that makes legs look shorter should also be complemented.

Differential effect of electroacupuncture analgesia depending on the point selection in a rat model of CFA-induced arthritis (CFA로 유도한 관절염에서 선혈(選穴)에 따른 전침(電鍼)의 진통효과 차이)

  • Yang, Bum-Sik;Koo, Sung-Tae;Kim, Kyoung-Sik;Sohn, In-Cheul
    • Korean Journal of Acupuncture
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    • v.22 no.1
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    • pp.95-108
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    • 2005
  • Objective : In the present study, the effect of electroacupuncture (EA) applied to several acupoints and non-acupoint in CFA-induced knee arthritis was examined. Methods : A common source of persistent pain in humans is arthritis. Arthritis was induced by injection of CFA $125\;{\mu}l$ into knee joint cavity under enflurane anesthesia. The rat subsequently showed swelling of the ankle and a reduced stepping force of the affected limb for the next several days. The reduced stepping force of the limb was presumably due to a painful knee. EA was applied to either of $LR_2,\;LI_4$, or non-acupoint on the contralateral forelimb for 30 min under gaseous anesthesia. After the termination of EA, behavioral tests measuring stepping force were periodically conducted during the next 4 h. Results : EA applied to $LR_2$ point produced a significant improvement of stepping force of the affected foot lasting for at least 2 h. However, neigher $LI_4$ point nor non-point produced any significant increase of weight bearing force. The improvement of stepping pressure was interpreted as an analgesic effect. The analgesic effect was specific to the acupuncture point since the analgesic effect on CFA-induced knee arthritic pain model could not be mimicked by EA applied to a point, $LI_4$ or non-acupoint. In addition, both NO production and iNOS protein expression increased by arthritis were suppressed by EA applied to $LR_2$ point. Conclusion : These data suggest that EA produces a potent analgesic effect in the rat model of CFA-induced knee arthritis. This analgesic effect is produced by applying EA to an acupoint at opposite side from the painful area in a stimulus point-specific way.

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A numerical method for improving the reliability of knee translation measurement in skin marker-based motion analysis

  • Wang, Hongsheng;Zheng, Nigel
    • Advances in biomechanics and applications
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    • v.1 no.4
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    • pp.269-277
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    • 2014
  • In skin-marker based motion analysis, knee translation measurement is highly dependent on a pre-selected reference point (functional center) on each segment determined by the location of anatomical landmarks. However, the placement of skin markers on palpable anatomical landmarks (i.e., femoral epicondyles) has limited reproducibility. Thus, it produces large variances in knee translation measurement among different subjects, as well as across studies. In order improve the repeatability of knee translation measurement, in this study an optimization method was introduced, by which the femoral functional center was numerically determined. At that point the knee anteroposterior translation during the stance phase of walking was minimized. This new method was tested on 30 healthy subjects during walking in gait lab with motion capture system. Using this new method, the impact of skin marker position (at anatomical landmarks) on the knee translation measurement has been minimized. In addition, the ranges of anteroposterior knee translations during stance phase were significantly (p<0.001) smaller than those measured by conventional method which relies on a pre-selected functional center ($11.1{\pm}3.5mm$ vs. $19.9{\pm}5.5mm$). The results of anteroposterior translation using this new method were very close to a previously reported knee translation (12.4 mm) from dual fluoroscopic imaging technique. Moreover, this new method increased the reproducibility of knee translation measurement by 50%.

Effects of Acupuncture applied to Food Samli on the Rat Model of Knee Arthritic Pain (족삼리(足三里) 전침(電鍼)이 백서(白鼠)의 슬관절염(膝關節炎) 통증(痛症)에 미치는 영향(影響))

  • Park, Sung-Ik;Koo, Sung-Tae;Hwang, Jae-Ho;Shin, Jong-Keun;Sohn, In-Chul;Kim, Kyung-Sik
    • Korean Journal of Acupuncture
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    • v.21 no.1
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    • pp.113-127
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    • 2004
  • Objectives : The usage of acupuncture has gained popularity as an alternative method of treatment for certain chronic pain conditions. However, the efficacy of acupuncture in various diseases has not been fully established and the underlying mechanism is not clearly understood. In the present study, the effect of electroacupuncture (EA) applied to foot samli$(ST_{36})$ on the carrageenan-induced knee arthritic pain was examined. Methods : A common source of persistent pain in humans is the knee arthritis. Knee arthritis was induced by injection of 2 % carrageenan $50\;{\mu}l$ into the knee joint cavity. When rats developed pain behaviors, EA was applied for 30 min. under enflurane anesthesia with repeated train stimuli at the intensity of 10X of muscle twitch threshold. The weight bearing force of the hind limb was measured for an indicator of pain level after each manipulation. Results : The average weight borne by the hind limb during normal gait was 55% of total body weight, which was reduced to less than 10% after knee arthritis. EA improved the weight bearing of the arthritic hind limb significantly for the duration of 4 hr. EA applied to $ST_{36}$ point produced a significant improvement of stepping force of the arthritic foot lasting for at least 4 h. However, $GB_{31}$ point did not produce any significant increase of weight bearing force. The analgesic effect was specific to the acupuncture point since the analgesic effect on the knee arthritis model could not be mimicked by EA applied to a nearby point, $GB_{31}$. The relations between EA-induced analgesia and endogenous nitric oxide(NO) and inducible NO synthase(iNOS)/neuronal NOS was also examined. Results were turned out that both NO production and nNOS/iNOS protein expression which is increased by arthritis were suppressed by EA stimulation applied to $ST_{36}$ point. Conclusions : The data suggest 1) that EA produces a potent analgesic effect on the rat model of chronic knee arthritis pain in a point specific manner and 2) that EA-induced analgesia modulate endogenous NO through the suppression of nNOS/iNOS protein expression.

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A Comparison analysis of kinematics of lower extremities for 1st position jump in ballet between two types of ballet shoes (발레의 1st Position 점프 동작 시 신발 유형에 따른 하지의 운동학적 비교분석)

  • Youm, Chang-Hong;Park, Young-Hoon;Seo, Kook-Woong
    • Korean Journal of Applied Biomechanics
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    • v.13 no.3
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    • pp.327-340
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    • 2003
  • The purpose of this study was to investigate the height of jump, angle of the ankle and knee, the angular velocity of the ankle and knee between two types of ballet shoes during a jump in the 1st position. The subjects were 5 female ballet majors of university in Busan the majors who have been dancing ballet for six years on the average. The conclusions are as follows: 1. The height of jump had no significant difference between two types of ballet shoes, and then the average of the height of jump with point shoes group ($20.24{\pm}4.62\;cm$) was a little higher than ballet shoes group ($17.50{\pm}4.05\;cm$). 2. The angle of the ankle had no significant difference for all events between two types of ballet shoes. The minimum angle of ankle joint was represented to $54.36_{\circ}$ at the E1 of the left ankle angle of the ballet shoes and the maximum value was showed $155.43_{\circ}$ at the E3 of the right ankle angle of the point shoes. 3. The angle of the knee had no significant difference for all events between two types of ballet shoes. The minimum angle of knee joint was represented to $99.54_{\circ}$ at the E1 of the left knee angle of the ballet shoes and the maximum value was showed $174.25_{\circ}$ at the E3 of the right knee angle of the point shoes. 4. The ankle velocity of the ankle had no significant difference for all events between two types of ballet shoes. The minimum angular velocity of the ankle was represented to 4.35 deg/s at the maximum height(E3) of the point shoes and the maximum value was showed 597.81 deg/s at the take-off(E2) of the right ankle angle of the point shoes. 5. The angular velocity of the knee had significant difference between two types of ballet shoes at the event 1(p<.05). The minimum angular velocity of the hee was represented to -1.68 deg/s at the maximum height(E3) of the point shoes and the maximum value was showed 360.25 deg/s at the take-off(E2) of the left knee angle of the ballet shoes. The other events had no significant difference between two types of ballet shoes.

The Effects of Visual Biofeedback Information on Hyperextended Knee Control

  • Jung, Sung-hoon;Jeon, In-cheol;Ha, Sung-Min
    • The Journal of Korean Physical Therapy
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    • v.33 no.3
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    • pp.162-167
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    • 2021
  • Purpose: A hyperextended knee is described as knee pain associated with an impaired knee extensor mechanism. Additionally, a hyperextended knee may involve reduced position sense of the knee joint that decreases the individual's ability to control end-range knee extension movement. The purpose of this study was to investigate the effects of visual biofeedback information for plantar pressure distribution on knee joint angle and lower extremity muscle activities in participants with hyperextended knees. Methods: Twenty-three participants with hyperextended knees were recruited for the study. Surface electromyography signals were recorded for the biceps femoris, rectus femoris, gastrocnemius, and tibialis anterior muscle activities. The plantar pressure distribution was displayed and measured using a pressure distribution measuring plate. Knee joint angle kinematic parameters were recorded using a motion analysis system. The visual biofeedback condition was the point at which the difference between the forefoot and backfoot plantar foot pressure on the monitor was minimized. The Wilcoxon signed-rank test was used to determine the significance between the visual biofeedback condition and the preferred condition. Results: The knee joint angle was significantly decreased in the visual biofeedback condition compared to that in the preferred condition (p<0.05). The rectus femoris and gastrocnemius muscle activities were significantly different between the visual biofeedback and preferred conditions (p<0.05). Conclusion: The results of this study showed that visual biofeedback of information about plantar pressure distribution is effective for correcting hyperextended knees.

Effects of the Visual Analog Scale and Knee Function Index on the Muscle Strength and Muscle Endurance of the Knees of Male National Field-Hockey Athletes (국가대표 남자 필드하키 선수들의 무릎의 시각적 상사 척도와 무릎 기능평가가 무릎의 근력 및 근지구력에 미치는 영향)

  • Kim, Hyun-Chul;Park, Ki-Jun
    • Journal of the Korean Society of Physical Medicine
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    • v.16 no.1
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    • pp.103-109
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    • 2021
  • PURPOSE: This study examined the effects of the Visual Analog Scale (VAS) and knee function index on the knee strength and endurance in the national male field-hockey athletes. METHODS: Twenty-four male field-hockey athletes with a painful knee who trained at the national training center in 2019 were enrolled. The VAS and knee function index questionnaire were used to evaluate the degree of pain and functional state of the knee. The muscle strength and endurance of the knee were measured by Biodex (System 4, USA). The Pearson product moment correlation was performed to examine the effects of the VAS and knee function index the of knee on the strength and endurance. In addition, the VAS and knee function index and muscle strength and muscle endurance were examined to determine the relationship using Simple Linear Regression. The statistical significance level was α=.05. RESULTS: An analysis of the correlation between VAS and knee function index and muscle strength and muscle endurance revealed the VAS and knee function index to be statistically significant (r = .700). In addition, the extensor muscle strength, knee VAS (r = -.457), and knee function index (r = -.414) were also statistically significant. A 1-point increase in the VAS and knee function index was associated with an approximately 9.881 and 1.006 extensor muscle strength. CONCLUSION: The VAS and knee function index of field-hockey athletes are related to the strength of the knee extensors. Therefore, field-hockey athletes should develop a program to strengthen the extensor muscle strength of the knee.

Study on Clinical Effects of Homnis Placenta Herbal Acupuncture on Osteoarthritis of Knee Joint (자하거(紫河車) 약침(藥針)의 퇴행성(退行性) 슬관절염(膝關節炎) 치료(治療)에 대한 임상적 고찰(考察))

  • Song, Kye-Hwa;Lee, Jin-Seok;Jo, Jin-Hyung;Park, Ki-Bum
    • Journal of Acupuncture Research
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    • v.23 no.4
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    • pp.163-173
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    • 2006
  • Objectives : The study was peformed to evaluate the effect of treatment for Osteoarthritis of knee joint by using Homnis Placenta Herbal Acupuncture. Methods : We investigated 60 cases of patient with Osteoarthritis of knee joint from 1st February 2005 to 31st January 2005, 60 cases of patient with Osteoarthritis in knee joint treated at the department of acupuncture & moxibustion of Kwang-Dong Oriental Medicine Hospital were randomly selected for two group. One group was treated by Homnis Placenta Herbal Acupuncture therapy, the other group was treated by Filiform Acupuncture therapy. We studied Lyshoim score, Ahlaback Grade, Nine-point scale and improvement degree of the grade of Ahlaback. Results : 1. In the Lyshoim score, Homnis Filiform Acupuncture was more effective than Filiform Acupuncture. But, there was no significance between two groups statistically in the Lyshoim score. 2. In the Nine point score, Homnis Placenta Herbal Acupuncture was more effective than Filiform Acupuncture. 3.In the improvement degree of the grade of Ahlaback., Homnis Placenta Herbal Acupuncture was as effective as Filiform Acupuncture. Conclusion : In the treatment of Osteoarthritis of knee joint, Homnis Placenta Herabl Acupuncture was not more effective than Filiform Acupuncture statistically. But both Homnis Placenta Herbal Acupuncture and Piliform Acupuncture was effective in Osteoarthritis of knee joint.

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