• Journal of Electrical Engineering and Technology
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• 제2권2호
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• pp.178-187
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• 2007

One important issue in power systems is dynamic instability due to loosing balance relation between electrical generation and a varying load demand that justifies the necessity of stabilization. Moreover, Power System Stabilizer (PSS) must have capability of producing appropriate stabilizing signals over a wide range of operating conditions and disturbances. To overcome these drawbacks, this paper proposes a new method for robust design of PSS by using an auto-tuning fuzzy control in combination with Real-Coded Genetic Algorithm (RCGA). This method includes two fuzzy controllers; internal fuzzy controller and supervisor fuzzy controller. The supervisor controller tunes the internal one by on-line applying of nonlinear scaling factors to inputs and outputs. The RCGA-based method is used for off-line training of this supervisor controller. The proposed PSS is tested in three operational conditions; nominal load, heavy load, and in the case of fault occurrence in transmission line. The simulation results are provided to compare the proposed PSS with conventional fuzzy PSS and conventional PSS. By evaluating the simulation results, it is shown that the performance and robustness of proposed PSS in different operating conditions is more acceptable

• 대한의용생체공학회:의공학회지
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• 제27권5호
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• pp.245-249
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• 2006

The aim of this study is to design and develop the gait rehabilitation equipment that judge patient's movement of his/her center of gravity using pressure sensors, and to aid hemiplegic patients to balance themselves using an automatic stepper that changes the patient's center of gravity. It is hard to bear the weight on the affected side for hemiplegic patients. The gait rehabilitation equipment detects the footing phase of hemiplegic patient during training and moves the unaffected footing side of the stepper up and moves the affected footing side down simultaneously so that the patient's center of gravity can shift from unaffected side to affected side. The gait rehabilitation system was developed and applied for hemiplegic patients during exercise. Eight hemiplegic patients and one normal adult were studied. The developed gait rehabilitation system could judge not only the normal adult's intention but also the patient's intention to move his/her center of gravity. Even though the most of hemiplegic patients exercised in automatic mode and a few hemiplegic patients exercised in manual mode, the developed gait rehabilitation system can aid the hemiplegic patients to train more easily.

• 국제물리치료학회지
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• 제11권1호
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• pp.1940-1949
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• 2020

Background: Self-checked monitoring home exercises are recommended for preventing falls among people with Parkinson's disease. However, as these home exercises are performed autonomously by patients without professional management, their accuracy and efficiency can be compromised. Objective: To investigate the effects of providing regular training sessions to patients and caregivers and of patient self-monitoring of exercise performance following the implementation of a self-checked monitoring exercise program for people with Parkinson's disease. Design: Randomized Pretest-Posttest Control Group Design. Methods: We provided regular self-checked monitoring home exercise and general home exercise programs to 30 participants for 12 weeks. Once a month at the first, fifth, and ninth-week sessions, a rehabilitation team attended the Parkinson's group education. In addition to the subject in the experimental group perform the home exercises program to provide feedback regarding the home exercises program and to carry out a self-monitoring checklist performance for 12 weeks. Results: The 10 m walk test, functional reach test, and sit to stand test and the modified Barthel index significantly improved in the self-checked monitoring home exercise group. Conclusion: These results suggest that self-checked home exercise programs, which facilitate safety and consistent performance of exercises at home, are beneficial for people with Parkinson's disease.

• Physical Therapy Rehabilitation Science
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• 제10권3호
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• pp.257-262
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• 2021

Objective: Patients with stroke generally diminished ankle range of motion, which decreases balance and walking ability. This study aimed to determine the effect of ankle self-mobilization with movement (s-MWM) on ankle dorsiflexion passive range of motion, timed up and go test, and dynamic gait index in patients with chronic stroke. Design: Randomized controlled trial design Methods: Twenty-four post-stroke patients participated in this study. The participants were randomized into the control (n = 12) and self-MWM groups (n = 12). Both groups attended standard rehabilitation therapy for 30 minutes per session. In addition, self-MWM group was performed 3 times per week for 8 weeks. All participants have measured ankle dorsiflexion passive range of motion, timed up and go test, and dynamic gait index in before and after the intervention. Results: After 8 weeks of training, self-MWM group showed greater improvement in ankle dorsiflexion passive range of motion, timed up and go test, and dynamic gait index than in the control group (p<0.05). Further, self-MWM group had significantly improvement in all dependent variables compared to the pre-test (p<0.05). Conclusions: Our investigation demonstrates that self-MWM is beneficial for improving functional ability. Also, self-MWM was superior to control with respect to improving ankle dorsiflexion passive range of motion, timed up and go test, and dynamic gait index.

• 융합정보논문지
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• 제9권8호
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• pp.243-247
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• 2019

본 연구는 6주간 20대의 일반 대학생을 대상으로 척추 정렬과 균형능력에 대한 클라이밍 운동 프로그램이 자기효능감에 미치는 영향에 대해 알아보았으며, 실험대상자는 총 30명이었으며, 6주간 주 3회 씩 상지와 하지에 대한 클라이밍 운동프로그램을 실시하였고, 결과는 다음과 같았다. 자기효능감의 군내 비교에서는 훈련군에서 유의한 차이가 있었다. 따라서, 클라이밍 운동이 자기효능감에 정상성인의 동기부여를 향상하는데 영향을 줄 수 있다는 것을 알 수 있었다. 결론적으로 추후 다양한 실험자들에게 클라이밍 운동을 실시할 시 참고 자료로 사용될 수 있을 것이라 사료된다.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2019년도 춘계종합학술대회
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• pp.385-386
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• 2019

본 연구의 목적은 균형에 이상이 있는 20대 정상 성인에게 혈류제한성 탄력밴드 훈련 적용 시 균형능력 회복에 미치는 효과를 알아보고자 하였다. 12명의 남성을 대상으로 대조군(n=6), 실험군(n=6)으로 무작위할당하였다. 두 군은 고강도 축구경기를 통한 균형능력 손상 유발 후 실험군은 1주일 3회 1시간씩 4주 동안 혈류제한성 탄력밴드 훈련을 실시하였고, 대조군은 아무런 훈련을 실시하지 않았다. 모든 대상자는 경기 전, 경기 후, 경기 4주 후에 정적 및 동적 균형을 측정하였다. 연구 결과, 정적균형에서 대조군은 경기 전으로 유의한 회복을 나타내지 않았으나, 실험군은 유의한 회복을 나타냈다. 동적균형에서는 대조군과 실험군 모두에서 유의한 회복을 나타냈다. 혈류제한성 탄력밴드 운동은 단기간에 효율적으로 근력을 향상시킴으로써 균형능력 회복에 긍정적 영향을 줄 수 있다고 판단된다.

• The Journal of Asian Finance, Economics and Business
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• 제8권2호
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• pp.635-641
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• 2021

This article analyzes the factors affecting income inequality in Vietnam, with data from 63 provinces and cities collected from the Vietnam Household Living Standards Survey of the General Statistics Office of Vietnam from 2010 to 2018. The article will firstly build a research model to identify factors affecting income inequality. Then, it uses the Generalized Method of Moments (GMM) method to evaluate the effect of factors on income inequality in Vietnam. The empirical estimate result shows that, in the period from 2010 to 2018, the factors such as the proportion of the working employees, income per capita, and inflation have positive effects on the Gini coefficient. That is, when these factors increase, there will be negative effects on improving income inequality in Vietnam. Conversely, when the factors such as the proportion of the literate adults, the proportion of the urban population, and population density increase they will have a positive impact on improving income inequality in Vietnam during this period. The estimated coefficients satisfied the sign expectation except the proportion of the literate adults. It means that, in Vietnam, the increase and more equilibrium in educational attainment balance the distribution of income and bring an improvement in income inequality.

• 산업경영시스템학회지
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• 제43권4호
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• pp.150-160
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• 2020

In this paper, we introduce a pilot's scheduling model which is able to maintain and balance their capabilities for each relevant skill level in military helicopter squadron. Flight scheduler has to consider many factors related pilot's flight information and spends a lot of times and efforts for flight planning without scientific process depending on his/her own capability and experience. This model reflected overall characteristics that include pilot's progression by basis monthly and cumulative flight hours, operational recent flight data and quickly find out a pinpoint areas of concern with respect to their mission subjects etc. There also include essential several constraints, such as personnel qualifications, and Army helicopter training policy's constraints such as regulations and guidelines. We presented binary Integer Programming (IP) mathematical formulation for optimization and demonstrated its effectiveness by comparisons of real schedule versus model's solution to several cases experimental scenarios and greedy random simulation model. The model made the schedule in less than 30 minutes, including the data preprocessing process, and the results of the allocation were more equal than the actual one. This makes it possible to reduce the workload of the scheduler and effectively manages the pilot's skills. We expect to set up and improve better flight planning and combat readiness in Korea Army aviation.

• International Journal of Knowledge Content Development & Technology
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• 제11권4호
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• pp.87-99
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• 2021

The study examines the relationship between co-operative society governance and members' satisfaction. Co-operative societies face problems of how to keep balance between efficiency and governance because those in charge of operations of co-operative; the board and the staff must meet two demands i.e. good business practice and the social responsibility which involves the satisfaction of members. The objective of this study is to examine the relationship between co-operative governance and members' satisfaction using Ambrose Alli University Workers/Farmers Multi -Purpose the Co-operative Society as a case study. The data collected in this study were obtained through structured questionnaire. Data analyzed were subjected to descriptive statistics and graphs. The data analyzed indicated that the challenges facing the co-operative society include theft /fraud and mismanagement. Members agitated for transformation of the co-operative society to operate in line with the guidelines of the Central Bank of Nigeria. It was recommended that for efficiency and high productivity, staff should be trained. Also there is need for innovative technology and the necessity for the cooperative society in question to network with other organizations.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권11호
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• pp.3780-3797
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• 2022

The estimation of radio map (RM) is a fundamental and critical task for the network planning and optimization performance of mobile communication. In this paper, a RM estimation method is proposed based on a deep dual learning structure. This method can simultaneously and accurately reconstruct the urban building map (UBM) and estimate the RM of the whole cell by only part of the measured reference signal receiving power (RSRP). Our proposed method implements UBM reconstruction task and RM estimation task by constructing a dual U-Net-based structure, which is named RadioCycle. RadioCycle jointly trains two symmetric generators of the dual structure. Further, to solve the problem of interference negative transfer in generators trained jointly for two different tasks, RadioCycle introduces a dynamic weighted averaging method to dynamically balance the learning rate of these two generators in the joint training. Eventually, the experiments demonstrate that on the UBM reconstruction task, RadioCycle achieves an F1 score of 0.950, and on the RM estimation task, RadioCycle achieves a root mean square error of 0.069. Therefore, RadioCycle can estimate both the RM and the UBM in a cell with measured RSRP for only 20% of the whole cell.