• Journal of Power Electronics
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• v.18 no.6
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• pp.1771-1779
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• 2018

Modern trams with a super capacitor have gained a lot of attention in recent years due to its reliability, convenience, energy conservation and environmental friendliness. Because of its special charging characteristic, the traditional charging structure and control strategy cannot satisfy its charging requirements. This paper presents a new charging topology for fast charging modern trams with a super capacitor and it designs a controller using continuous control set model predictive control (CCS-MPC). There are three contributions in this paper. First, a new charging structure is designed and its mathematics model is derived. The cascade structure is adopted instead of the parallel structure to simplify the control process and to keep the rated power of the controllable part low. Second, a MPC control strategy is proposed to satisfy the charging characteristic. The optimal control signal can be obtained by solving the designed optimization problem. The optimal control signal is related to the discrete control action. In addition, mapping between the continuous control signal and the discrete control action is designed. Third, a semi-physical experimental platform is built to verify the proposed topology and control method. The simulation model and experiment platform are built to verify the correctness of the new structure and its control method. The results obtained show that the new topology can work effectively.

• Environmental Analysis Health and Toxicology
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• v.20 no.4 s.51
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• pp.259-271
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• 2005

Engineered nanoparticles exhibit a variety of unique and tunable chemical and physical properties. These unique properties make the nanoparticles central components and widespread potential applications in nanoindustry. However, the potential toxicities of nanoparticles have not been fully evaluated. Recently, the impacts of nanoparticles to human and environment became the emerging issue of toxicology. In this article, physicochemical properties and toxicities of carbon nanotube, fullerene, quantum dots, and other types of nanomaterials were reviewed and the strategy of risk assessment were suggested based on the frame of chemical assessment.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10a
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• pp.1122-1126
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• 1991

As microcomputers have become widespread and the high speed solenoid valves have been developed, digitally controlled hydraulic systems are used in many applications. This study deals with position control of hydraulic cylinder operated by two port 3-way high speed solenoid valve using a self-learning strategy. This was done by developing a control algorithm for the microcomputer which always automatically adjust the length of control pulse to the optimum value in accordance with the error regardless of changes in the operating condition and physical differences between components. Tests carried out in the laboratory indicate that a positional accuracy could be improved.

• Korean Journal of Organic Agriculture
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• v.19 no.4
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• pp.475-500
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• 2011

One of the first important strategic decisions when a starting an organic marketing initiative (OMI) is to plan the right strategy for distributing products. This decision depends to a large extent on whether the OMI has chosen a quality-premium product strategy or a price-quantity strategy. All distribution decisions interact strongly with other aspects of the marketing mix. Where and how a product is distributed objectives, its chosen strategy and the availability of human and capital resources. To select a market channel, frequent contact and discussions with possible partner are important. Generally, a distribution is made between the direct and indirect physical distribution of organic products to consumers. The longer the supply chain, the lower the chances that an OMI can steer the market through its own marketing measures and convince consumers through its own promotion activities. Generally speaking, the shorter the chain between OMI products and the final consumer, the less dependent the OMI will be on the success of other market actors. Direct selling activities to the retail or food industries also requires an OMI to undertake additional processing and marketing activities. For example, retailers often expect products to have been packed and labelled ready for sale. To conclude, distribution channels should be chosen in accordance with the product and price policy as well as the management capacity of the OMI.

• Journal of Korean Academy of Medicine & Therapy Science
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• v.10 no.2
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• pp.59-71
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• 2018

Objective: The purpose of this study is to compare the effects of the CO-OP program using cognitive strategy on the satisfaction and high-level cognitive function of chronic stroke patients with cognitive impairment with the existing task-oriented approach training method. Method: The group randomly selects the experimental group and control group from 30 patients who suffer cognitive damage due to brain damage, and then randomly presents the Cognitive Orientation to daily Occupative Performance (CO-OP) Results: The results of the study showed a significant increase in patient performance and satisfaction, task performance, and high-level cognitive functions in comparison to those before training (p<).05) There was no significant difference in CNT testing in controls; Although there were no significant differences in overall CNT testing between the two groups, the COPM, AMPS tests showed a significant increase in the experimental group compared to the comparators (p <.05). Conclusion: The Cognitive Orientation to Daily Occupative Performance (CO-OP) Intervention Act, which uses meta-in strategies, was previously used. We were able to confirm that it could be a more effective intervention in task performance and high-level cognitive function than in the Meaningful Task-Specific Training Program (MTST).

• International Journal of Contents
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• v.15 no.2
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• pp.59-74
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• 2019

The objective of this study was to analyze the influence of physical education classes based on Flipped Learning on self-directed learning abilities and learning attitude towards these classes, for middle school students. The study selected 90 students as an experimental group (3 classes) and 97 students as a control group (3 classes), among 240 students of the first-year students attending a middle school located at Jeonju City of South Korea, applying convenience sampling, one of the non-probability sampling methods. For the experimental group, 36 sessions of physical education classes were held for 14 weeks, while the control group received teacher-centered classes. Comparing the results with the control group, the experimental group showed significant differences in terms of all sub factors of self-directed learning abilities, namely; desire for learning, learning objective establishment, basic self-management abilities, selection of learning strategy and self-reflection. Moreover, the experimental group manifested significant differences in terms of all sub factors of attitude towards the physical education subjects, namely; positive emotions, negative emotions, health & physical strength, interpersonal relations, physical activities & movements, and active participation & positive performance. From the findings, it can be considered that physical education classes based on Flipped Learning contributed to improving self-directed learning abilities and attitude towards physical education classes. This result can serve as a significant basic material for designing and performing classes in raising the understanding of Flipped Learning and effectively applying Flipped Learning in physical education classes.

• Journal of Information Technology Services
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• v.21 no.5
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• pp.95-106
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• 2022

Recently, physical examinations have become an important strategy to reduce costs for individuals and society. Pre-physical counseling is important for an effective physical examination. However, incomplete counseling is being conducted because the demand for physical examinations is not predicted. Therefore, in this study, the demand for physical examination was predicted using text mining and stepwise regression. As a result of the analysis, the most recent text data showed a high explanatory power of the demand for physical examination. Also, large amounts of data have high explanatory power. In addition, it was found that the high frequency of the text "health food" reduces the number of health examination customers. And the higher the frequency of the text of the word "food", the lower the number of physical examination customers. However, when the word "wild ginseng" was exposed a lot on Twitter, the number of physical examination customers visiting hospitals increased. In other words, customers consume efficiently by comparing the health examination price with the price of consumer goods. The proposed research framework can help predict demand in other industries.

• Journal of information and communication convergence engineering
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• v.15 no.1
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• pp.14-20
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• 2017

In this paper, we discuss physical layer security techniques in downlink networks, including eavesdroppers. The main objective of using physical layer security is delivering a perfectly secure message from a transmitter to an intended receiver in the presence of passive or active eavesdroppers who are trying to wiretap the information or disturb the network stability. In downlink networks, based on the random feature of channels to terminals, opportunistic user scheduling can be exploited as an additional tool for enhancing physical layer security. We introduce user scheduling strategies and discuss the corresponding performances according to different levels of channel state information (CSI) at the base station (BS). We show that the availability of CSI of eavesdroppers significantly affects not only the beamforming strategy but also the user scheduling. Eventually, we provide intuitive information on the effect of CSI on the secrecy performance by considering three scenarios: perfect, imperfect, and absence of eavesdropper's CSI at the BS.

• Journal of Korean Physical Therapy Science
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• v.18 no.4
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• pp.47-58
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• 2011

The purpose of this study was to analyses the main factors of research papers for related with home physical therapy. This study was retrospective descriptive study, the period of data collection was from 1991 to 2011. The data was collected by the journal related in physical therapy, the dissertation of academic degree, National Assembly Library and the web-site for academic information. In the web-site, searched with the keyword 'home physical therapy' and 'after school voucher'. The results were as follows; 1. In the home physical therapy, visiting physical therapy, school physical therapy, there were different based on laws; home physical therapy was based on medical law, visiting physical therapy was based on law for community health and law for long term health insurance, school physical therapy was based on special education law. 2. The summary of research title/thema from 1991 to 2011 was as follows; for the home and visiting physical therapy 'the needs and necessity of home and visiting physical therapy' was 18 papers, 'the contents of service of home and visiting physical therapy' was 18 papers, 'program and skill development' was 16 papers, 'system developing and induction strategy of home and visiting physical therapy 'was 15 papers, 'costs of nome and visiting physical therapy' was 2 papers, 'perception and information of home and visiting physical therapy' was 9 papers, 'Recoding system and administration management' was 9 papers, 'the others 'was 14 papers, for the school physical therapy 'after school voucher system' was 9 papers, the others was 4 papers. The total papers was 114 papers. 3. Finally suggested 'Model of Educational Program for HomeVisiting and School Physical Therapy'.

• Journal of The Korean Association For Science Education
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• v.21 no.2
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• pp.289-298
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• 2001

The effect of the instructional approach that asked students to check their problem-solving processes through a paired think-aloud problem solving after presenting molecular-level pictures and a four stage-problem solving strategy was investigated. Four high school classes (N = 191) were randomly assigned to St group (using Strategy individually), SL group (Solver Listener), St-SL group (using Strategy-Solver Listener), and control group. Although the test scores of the St-SL group on strategy performing ability were significantly higher than those of the control group, there was not significant difference for the scores in the multiple-choice algorithmic problems. Regarding the subcategories of strategy performing ability test, students' ability of understanding given of problems and deriving the proper physical quantity was improved, but their ability of setting up subgoals and reviewing their solving process was very low. The preference to the strategy of the St-SL group was more positive than that of the St group.