• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2004년도 춘계학술대회 논문집
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• pp.135-140
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• 2004

본 논문에서는 비 홀로노믹적인 구속조건을 갖는 수중 이동체의 위치 및 자세제어에 관한 제어기법에 대해서 논의한다. 비 홀로노믹 시스템은 적분 불가능한 구속조건으로부터 도출되어지는 시스템으로 연속시간영역의 피트백제어로는 평형점에서의 안정화제어가 불가능한 특성을 가지고 있다. 본 연구에서는 속도의 비 홀로노믹 구속조건을 가지는 수중 이동체에 대하여 체인트폼으로 변환하고 변환된 시스템에 대해 백스테핑 제어기법을 적용하여 자세제어를 행하고 수치시뮬레이션을 통하여 제어기법의 유용성을 평가하였다.

• The Journal of Korean Physical Therapy
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• 제33권1호
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• pp.1-6
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• 2021

Purpose: This study examined the effects of heel insoles on the static balance and leg muscle activity and posture control strategy during external perturbation. Methods: Thirty healthy young men participated in the study. The subjects underwent two experimental conditions: 1) no heel insole condition (0cm) and 2) wearing heel insole condition (5cm). The static balance was measured using an I-Balance device, which measured the change in the center of gravity (COG). The onset time of muscle activation and muscle activation of the erector spinae (ES), hamstring (HAM), gastrocnemius (GCM) were measured using surface EMG electrodes to determine the change in posture control strategy during external perturbation. Results: The speed and distance of COG were significantly higher in the wearing heel insoles condition than the no heel insole condition (p<0.05). In addition, significant differences in the onset time of the GCM, HAM, and ES muscle activation were observed when there was no heel insole condition during external perturbation (p<0.017). On the other hand, no significant differences in the onset time of muscle activation were observed between GCM and HAM when wearing the heel insole condition during external perturbation (p<0.017). Moreover, muscle activation of the GCM was significantly higher in the wearing heel insoles condition than the no heel insole condition during external perturbation (p<0.05). Conclusion: These findings suggest that heel insoles may have disadvantages, and increased efforts are needed to maintain balance and change the posture control strategy during external perturbation.

• 한국항해항만학회지
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• 제28권6호
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• pp.469-474
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• 2004

본 논문에서는 비 홀로노믹적인 구속조건을 갖는 수중 이동체의 위치 및 자세제어에 관한 제어기법에 대해서 논의한다. 비 홀로노믹시스템은 적분 불가능한 구속조건으로부터 도출되어지는 시스템으로 연속시간영역의 피드백제어로는 평형점에서의 안정화제어가 불가능한 특성을 가지고 있다. 본 연구에서는 속도의 비 홀로노믹 구속조건을 가지는 수중 이동체에 대하여 체인드폼으로 변환하고 변환된 시스템에 대해 백스테핑 제어기법을 적용하여 자세제어를 행하였으며 수치시뮬레이션을 통하여 제어기법의 유용성을 평가하였다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2004년도 추계학술대회
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• pp.41-46
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• 2004

본 논문에서는 속도 구속조건을 갖는 수중이동체를 초기위치로부터 목적위치에 접안하는 제어기법에 대해서 논의한다. 단, 수중이동 체는 일정방향으로 속도성분을 갖지 않는 즉, 속도구속조건을 가지는 것으로 가정한다. 본 논문에서는 이러한 시스템에 대하여 비 홀로노믹적인 관점에서 시스템을 해석하고 수중이동체를 체인드폼으로 변환한 후 Multi-rate 디지털 제어기법을 적용하여 자세제어를 행하고 수치시뮬레이션을 통하여 제어기법의 유용성을 평가하였다.

• Journal of Mechanical Science and Technology
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• 제18권4호
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• pp.649-663
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• 2004

While a great number of studies on human motor control have provided a wide variety of viewpoints concerning the strategy of the central nervous system (CNS) in controlling limb movement, none were able to reveal the exact methods how the movement command from CNS is mapped onto the neuromuscular activity. As a preliminary study of human-machine interface design, the characteristics of human leg motion and its underlying motor control scheme are studied through experiments and simulations in this paper. The findings in this study suggest a simple open-loop motor control scheme in leg motion. As a possible candidate, an equilibrium point control model appears consistent in recreating the experimental data in numerical simulations. Based on the general leg motion analysis, the braking motion by the driver's leg is modeled.

• 한국운동역학회지
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• 제18권1호
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• pp.245-253
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• 2008

본 연구의 목적은 유선형 신발바닥면을 가진 신발의 착용이 자세의 변화 및 조절전략에 미치는 영향을 살펴보는 것이다. 먼저 30명의 여대생을 대상으로 신발의 족저면과 접지면의 상대각도가 조절된 상태에서 'New York State Posture Test'로 평가하여 최적의 각도의 신발(s)을 제작한 후 여대생 10명씩 3개 집단에 대해 각각 제작된 신발(s)과 유선형 신발(m), 일반신발(n)의 8주착용 전 후의 전경골근, 비복근의 근활성도를 평가하였다. 1. 'New York State Posture Test'에서의 자세평가점수는 신발의 각도변화에 따라 $-2^{\circ}$, $-7^{\circ}$에서 쌍봉형을 이루었으며 통계적으로 유의하였다. 또한 $-7^{\circ}$에서 가장 좋은 평가점수가 나왔으므로 이 각도로 신발을 제작하였다. 2. 유선형의 아웃솔을 가진 s, m 신발의 활성패턴을 보면 맨발에서 s신발 착용자의 경우 비복근, m신발 착용자는 전경골근의 활성도가 증가하였으며, 신발을 착용한 상태에서는 s신발에서만 비복근의 활성도가 높게 나타났다.

• International Journal of Computer Science & Network Security
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• 제23권12호
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• pp.1-12
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• 2023

Ensuring the security of Supervisory Control and Data Acquisition (SCADA) and Industrial Control Systems (ICS) is paramount to safeguarding the reliability and safety of critical infrastructure. This paper addresses the significant threat posed by reconnaissance attacks on SCADA/ICS networks and presents an innovative methodology for enhancing their protection. The proposed approach strategically employs imbalance dataset handling techniques, ensemble methods, and feature engineering to enhance the resilience of SCADA/ICS systems. Experimentation and analysis demonstrate the compelling efficacy of our strategy, as evidenced by excellent model performance characterized by good precision, recall, and a commendably low false negative (FN). The practical utility of our approach is underscored through the evaluation of real-world SCADA/ICS datasets, showcasing superior performance compared to existing methods in a comparative analysis. Moreover, the integration of feature augmentation is revealed to significantly enhance detection capabilities. This research contributes to advancing the security posture of SCADA/ICS environments, addressing a critical imperative in the face of evolving cyber threats.

• 한국산학기술학회논문지
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• 제22권3호
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• pp.291-296
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• 2021

본 연구는 머리전방자세가 증가함에 따른 턱관절의 최대 개구량, 관자근과 깨물근의 근활성도, 근육의 비대칭률에 미치는 영향을 알아보고자 진행하였다. 연구 참가자들의 머리척추각을 측정하여, 연구의 선정요구를 충족시키는 머리 척추각이 50° 이상인 대상자 50명(23.10±2.73세)을 선정하였다. 머리전방자세를 증가시키기 위해 머리척추각을 0%, 10%, 20%를 감소시켜 Control I, Control II, Control III으로 설정하였다. 각 조건에 따른 턱관절의 최대 개구량, 관자근과 깨물근의 근활성도와 비대칭률의 변화를 측정하였다. 연구 결과, 머리척추각의 감소에 따라 최대 개구량은 유의하게 감소하였다(p<.001). 조건 변화에 따른 근활성도 변화를 측정한 결과, 오른쪽 관자근과 깨물근 및 왼쪽 관자근의 근활성도는 감소하였으며(p<.001), 왼쪽 깨물근의 근활성도도 감소하였다(p<.01). 조건 변화에 따른 근육의 좌우 비대칭률을 측정한 결과 좌우 관자근의 비대칭률, 좌우 관자근과 깨물근을 더한 근육의 비대칭률은 증가하였다(p<.01). 본 연구 결과는 턱관절 부위에 대한 치료 전략과 종합적 진단을 세우고, 턱관절 장애 치료를 위해 사용된 도수치료와 치료적 운동의 이론적 근거를 제시하는 데 도움이 될 것으로 사료된다.

• 한방재활의학과학회지
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• 제19권3호
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• pp.69-80
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• 2009

Objectives : The purpose of this study was to evaluate the effects of core stability training on postural control and balance of hemiplegia patients who are difficult to control posture due to stroke. Methods : Subjects of the study were consisted of 25 adult hemiplegia patients(experimental 12, control 13) who were receiving rehabilitation therapy in hospital. Its group had a core stability training program by a physical therapists for 40 minutes, five times a week for nine-week period. Measurements of postural assessment scale for stroke(PASS), berg balance scale(BBS) and manual function test(MFT) were evaluated at initial presentation(pretest) and after completion of the each therapy program(posttest). Independent t-test and paired t-test was utilized to detect the mean difference between the groups. Results : Firstly, the result of PASS showed that postural control was significantly increased after the completion of core stability training(p<.01). Secondly, the result of BBS showed that balance control was significantly increased after the completion of core stability training(p<.01) and general physical therapy(p<.01). Lastly, the result of MFT showed that upper extremity's motor function was significantly increased after the completion of core stability training(p<.001). Conclusions : This study showed that core stability training is an effective treatment strategy on postural control, balance and upper extremity's motor function.

• 한국운동역학회지
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• 제28권4호
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• pp.213-218
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• 2018

Objective: The purpose of this study was to examine the effect of the core muscle strength enhancement of the elderly on 8 weeks training using the core exercise equipment for the elderly on the ability to control the whole-body center of mass in posture stabilization. Method: 16 females (10 exercise group, 6 control group) participated in this study. Exercise group took part in the core strength training program for 8 weeks with total of 16 repetitions (2 repetitions per week) using a training device. External perturbation during standing as pulling force applied at the pelvic level in the anterior direction was provided to the subject. In a UCM model, the controller selects within the space of elemental variables a subspace (a manifold, UCM) corresponding to a value of a performance variable that needs to be stabilized. In the present study, we were interested in how movements of the individual segment center of mass (elemental variables) affect the whole-body center of mass (the performance variable) during balance control. Results: At the variance of task-irrelevant space, there was significant $test^*$ group interactions ($F_{1,16}=7.482$, p<.05). However, there were no significant main effect of the test ($F_{1,16}=.899$, p>.05) and group ($F_{1,16}=1.039$, p>.05). At the variance of task-relevant space, there was significant $test^*$ group interactions ($F_{1,16}=7.382$, p<.05). However, there were no significant main effect of the test ($F_{1,16}=.754$, p>.05) and group ($F_{1,16}=1.106$, p>.05). Conclusion: The results of this study showed that the 8 weeks training through the core training equipment for the elderly showed a significant decrease in the $Vcm_{TIR}$ and $Vcm_{TR}$. This result indicates that the core strength training affects the trunk stiffness control strategy to maintain balance in the standing position by minimizing total variability of individual segment CMs.