• Perspectives in Nursing Science
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• v.8 no.2
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• pp.148-155
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• 2011

Purpose: The aims of this study were to (1) summarize the HF self-management interventions and (2) identify gaps and priorities for further investigation. Methods: A computer search of the literature over the past decade yielded 9 HF self-management studies. Six studies used non-experimental design; only 3 (33%) studies used quasi-experimental design which were included in this review. Results: The three pivotal HF self-management interventions studies were important because they highlight the positive effects of self-management compliance and other quality of life outcomes as well as discussing various issues. The informational booklet and telephone follow-up were the most common modalities in these interventions. The periodic telephone counseling offered in 2 studies effectively facilitated patient self-management compliance. There were some methodological flaws such as small sample sizes (range 8~21 in each group) and lack of experimental designs, long-term follow-up, and random group assignment. Additionally, the use of valid, reliable outcome measures is necessary to compare the effects of the interventions worldwide. Conclusion: More clinical evidence on HF self-management is needed using a larger sample size and the efficacy needs to be tested for various outcomes, including morbidity, mortality, and health care cost.

• 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.

• Elastomers and Composites
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• v.40 no.2
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• pp.128-135
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• 2005

Optimal conditions for preparation of starch/PVA blends were investigated with the consideration of factors that may influence mechanical properties of the blends. $L_{27}(3^{13})$ experimental designs based on Taguchi method were performed and then tensile strength, strain at break, Young's modulus and tear strength of films of the blends were measured to determine the optimal conditions for preparation. Interaction effects for each factor were determined from analysis of variables. Results of $L_{27}(3^{13})$ experiments indicated that glycerol and urea were important process factors affecting optimization of the mechanical properties.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.6
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• pp.593-601
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• 2020

Two-dimensional laboratory experiments were conducted in a wave flume to investigate the wave transmission phenomena of impermeable-type submerged structures armored by concrete blocks. Different experimental conditions were included by considering relative crest depth, relative freeboard, relative crest width, wave steepness, and so on. An empirical formula was proposed to predict the wave transmission coefficients over various specifications and structural designs of the impermeable submerged structure from the experimental results. The proposed formula successfully predicted the wave transmission coefficients. Therefore, in this study, the proposed empirical formula of the wave transmission over an impermeable submerged structure was improved from the existing formula.

• Wind and Structures
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• v.33 no.6
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• pp.437-446
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• 2021

As wind turbine rotors increase, the overall loads and dynamic response become an important issue. This problem is augmented by the exposure of wind turbines to severe atmospheric events with unconventional flows such as tornadoes, which need specific designs not included in standards and codes at present. An experimental study was conducted to analyze the loads induced by a tornado-like vortex (TLV) on horizontal-axis wind turbines (HAWT). A large-scale tornado simulation developed in The Wind Engineering, Energy and Environment (WindEEE) Dome at Western University in Canada, the so-called Mode B Tornado, was employed as the TLV flow acting on a rigid wind turbine model under two rotor operational conditions (idling and parked) for five radial distances. It was observed that the overall forces and moments depend on the location and orientation of the wind turbine system with respect to the tornado vortex centre, as TLV are three-dimensional flows with velocity gradients in the radial, vertical, and tangential direction. The mean bending moment at the tower base was the most important in terms of magnitude and variation in relation to the position of the HAWT with respect to the core radius of the tornado, and it was highly dependent on the rotor Tip Speed Ratio (TSR).

• Wind and Structures
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• v.34 no.3
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• pp.303-312
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• 2022

As wind turbine rotors increase, the overall loads and dynamic response become an important issue. This problem is augmented by the exposure of wind turbines to severe atmospheric events with unconventional flows such as tornadoes, which need specific designs not included in standards and codes at present. An experimental study was conducted to analyze the loads induced by a tornado-like vortex (TLV) on horizontal-axis wind turbines (HAWT). A large-scale tornado simulation developed in The Wind Engineering, Energy and Environment (WindEEE) Dome at Western University in Canada, the so-called Mode B Tornado, was employed as the TLV flow acting on a rigid wind turbine model under two rotor operational conditions (idling and parked) for five radial distances. It was observed that the overall forces and moments depend on the location and orientation of the wind turbine system with respect to the tornado vortex centre, as TLV are three-dimensional flows with velocity gradients in the radial, vertical, and tangential direction. The mean bending moment at the tower base was the most important in terms of magnitude and variation in relation to the position of the HAWT with respect to the core radius of the tornado, and it was highly dependent on the rotor Tip Speed Ratio (TSR).

• Journal of the Ergonomics Society of Korea
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• v.21 no.2
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• pp.71-86
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• 2002

This study's purpose is to gain basic data for the factory automation of manufacturing custom-made girdles. For this study , obese women in their 30s and 40s was experimented through direct measuring and by the 3D scanner, by means of which the proportions of the subject's body was measured. Based upon the results of this experiment, individually designed girdles were made. In order to gain the basic data for the factory automation of manufacturing custom-made girdles, the patterns and the clothing pressure and the feeling of wearing such girdles were analyzed. This study can be summarized as follows: The material properties and the designs of existing functional girdles in the market were studied thoroughly, and the subject were required to wear those existing girdles. On the basis of this result, the experimental girdles were designed and produced which could serve well the subject's intension. The experimental girdles were of the basic long-type in order to apply to all sorts of girdles, and they were produced according to the style and pattern of the existing grading system. The second experiment was conducted by applying the subject's body measurements. Due to the elasticity of the material, in girdles the smaller measurements were to be used in this second experiment were: 80% of waist size, 84% of the hip and 85% of the thigh. To determine the length of the girdles, the same measurements were applied. The test results of the feeling of wearing the experimental girdles showed that the second, custom-made experimental girdles were better. According to the test results of the clothing pressure, the second experimental girdles(custom-made girdles) marked the higher pressure than the first on every part of the body, especially on the hips and thighs. Thus, it can be said that the second experimental girdles are better than the first in lifting up the hips. It is expected that the design methods developed in this study can be utilized as basic resources for the factory automation system of manufacturing custom-made girdles.

• Women's Health Nursing
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• v.19 no.4
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• pp.306-317
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• 2013

Purpose: This study was done to evaluate quality of reports of non-randomized controlled quasi-experimental study articles published in the Korean Journal of Women Health Nursing (KJWHN). Methods: A search was done for experimental studies assessing intervention effects among all articles published in the KJWHN from 2008 to 2013. Original articles were reviewed and analyzed according to the 22 checklist items of the guidelines for Transparent Reporting for Evaluations with Non-randomized Designs (TREND). Results: Thirty-five articles on experimental studies were identified. The evaluation of the quality of reporting in these experimental studies found that there was a wide variety in the level of satisfying the TREND checklist. In particular, according to TREND topics, low levels of reporting quality were found for "title & abstract (only for information on how units were allocated to the intervention)", "outcomes in methods", "assignment in methods", "blinding in methods", "recruitment in results", "baseline data in results", "interpretation in discussion (especially intervention mechanism and success or barriers), "generalizability in discussion". Conclusion: Results indicate that adherence to TREND guidelines varied in experimental studies published in the KJWHN suggesting the recommendation that for higher levels of complete reporting, TREND guidelines be used in reports on experimental studies.

• Restorative Dentistry and Endodontics
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• v.18 no.2
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• pp.395-411
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• 1993

The purpose of this study was to examine the clear concept of the designs for cavity preparations. Among the several parameters in cavity designs, profound understanding of isthmus width factor would facilitate selection of the appropriate cavity preparation for a specific clinical situation. In this study, the cavities were prepared on maxillary first premolar and filled with gold inaly. A two - dimensional model was composed of 1037 - node triangle elements. In this model, isthmus was varied in width at 1/4, 1/3 and 1/2 of intercuspal width and material properties were given for four element groups, i.e., enamel, dentin, pulp and gold. The 500N occlusal load varied in direction and it was examined using three types of load : concentrated load, divided load and distributed load. The models were also examined with empty cavities using the devided load and distributed load. These models were analyzed the displacement and strees distribution by the two - dimensional Finite Element Method. The results were as follows : 1. All experimental models which filled with gold inlay after cavity preparation were similar direction of displacement with control model under same load type. But in the models with empty cavities, as isthmus width was wider, the degree of displacement was increased at same load type. 2. Among the experimental models which were filled with gold inaly after cavity preparation, the model II showed the least stress concentration under concentrated load and divided load. But in the models with empty cavities, the model III showed the largest stress concentration and tooth fracture is expected regardless isthmus width. 3. All experimental models showed similar displacement pattern beneath restorative material under a concentrated load. In the models with empty cavities, a divided load resulted in a lingual displacement of the lingual cusp, but a distributed load resulted in a buccal displacement of the lingual cusp. In regard to the above results, the restored models were stronger than empty models in respect to the bending moment and tensile stress. The empty models are expected to fracture regardless isthmus width. The safest isthmus width was 1/3 of intercuspal distance, which showed the least stress concentration in respect to the effect of stress distribution.

• Journal of the Korean Institute of Gas
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• v.20 no.4
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• pp.78-84
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• 2016

In this work, finite element investigations were carried out to optimize reverse drawing process design for manufacture of high-capacity aluminum liner used in fuel cell vehicle. The tensile tests with aluminum alloy Al6061 annealed at $350^{\circ}C$ were carried out to obtain the flow stresses. In order to estimate more accurate flow stresses after necking, the flow stresses were estimated from the comparison of load vs. displacement curves which were obtained from experimental and simulation results of tensile tests. In case of finite element analyses of reverse drawing processes, it was focused on the effects of process designs such as punch and die designs, blank holding force, drawing ratio and the clearance between the punch and blank holder on the generation of wrinkle and fracture of the blank and partially heated punch. However, it was revealed that experimental results still show the fracture at the end of 2nd drawn cup, although partially heated punch is used. Nevertheless, the drawn cup can be used because the sufficient length of the drawn cup for the next flow forming process and spinning process was obtained.