• Design & Manufacturing
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• v.16 no.4
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• pp.34-39
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• 2022

Sustained economic development around the world is accelerating resource depletion. Research and development of secondary batteries that can replace them is also being actively conducted. Secondary batteries are emerging as a key technology for carbon neutrality. The core of an electric vehicle is the battery (secondary battery). Therefore, in this study, the temperature change by the heat source of the hammer and the rotational speed (rpm) of the abrasive disc of the Classifier Separator Mill (CSM) was repeatedly calculated and analyzed using the heat flow simulation STAR-CCM+. As the rotational speed (rpm) of the abrasive disk increases, the convergence condition of the iteration increases. Under the condition that the inlet speed of the Classifier Separator Mill (CSM) and the heat source value of the disc hammer are the same, the disc rotation speed (rpm) and the hammer temperature are inversely proportional. As the rotational speed (rpm) of the disc increases, the hammer temperature decreases. However, since the wear rate of the secondary battery material increases due to the strong impact of the crushing rotational force, it is determined that an appropriate rpm setting is necessary. In CSM (Classifier Separator Mill), it is judged that the flow rate difference is not significantly different in the direction of the pressure outlet (Outlet 1) right above the classifier wheel with the fastest flow rate. Because the disc and hammer attachment technology is adhesive, the attachment point may deform when the temperature of the hammer rises. Therefore, it is considered necessary to develop high-performance adhesives and other adhesive technologies.

• Structural Engineering and Mechanics
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• v.86 no.1
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• pp.119-137
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• 2023

The purpose of this research is to assess the performance of CBN and ceramic tools during the dry turning of gray cast iron EN GJL-350. During the turning operation, the variable machining parameters are cutting speed, feed rate, depth of cut and type of the cutting material. This contribution consists of two sections, the first one deals with the performance evaluation of four materials in terms of evolution of flank wear, surface roughness (2D and 3D) and cutting forces. The focus of the second section is on statistical analysis, followed by modeling and optimization. The experiments are conducted according to the Taguchi design L₃₂ and based on ANOVA approach to quantify the impact of input factors on the output parameters, namely, the surface roughness (Ra), the cutting force (Fz), the cutting power (Pc), specific cutting energy (Ecs). The RSM method was used to create prediction models of several technical factors (Ra, Fz, Pc, Ecs and MRR). Subsequently, the desirability function approach was used to achieve a multi-objective optimization that encompasses the output parameters simultaneously. The aim is to obtain optimal cutting regimes, following several cases of optimization often encountered in industry. The results found show that the CBN tool is the most efficient cutting material compared to the three ceramics. The optimal combination for the first case where the importance is the same for the different outputs is Vc=660 m/min, f=0.116 mm/rev, ap=0.232 mm and the material CBN. The optimization results have been verified by carrying out confirmation tests.

• Restorative Dentistry and Endodontics
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• v.46 no.4
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• pp.51.1-51.13
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• 2021

Objectives: This study aimed to evaluate the effect of improper positioning single-peak and multi-peak lights on color change, microhardness of bottom and top, and surface topography of bulk fill and incremental composites after artificial aging for 1 year. Materials and Methods: Bulk fill and incremental composites were cured using multi-peak and single-peak light-emitting diode (LED) following 4 clinical conditions: (1) optimal condition (no angulation or tip displacement), (2) tip-displacement (2 mm), (3) slight tip angulation (α = 20°) and (4) moderate tip angulation (α = 35°). After 1-year of water aging, the specimens were analyzed for color changes (ΔE), Vickers hardness, surface topography (Ra, Rt, and Rv), and scanning electron microscopy. Results: For samples cured by single-peak LED, the improper positioning significantly increases the color change compared to the optimal position regardless of the type of composite (p < 0.001). For multi-peak LED, the type of resin composite and the curing condition displayed a significant effect on ΔE (p < 0.001). For both LEDs, the Vickers hardness and bottom/top ratio of Vickers hardness were affected by the type of composite and the curing condition (p < 0.01). Conclusions: The bulk fill composite presented greater resistance to wear, higher color stability, and better microhardness than the incremental composite when subjected to improper curing. The multi-peak LED improves curing under improper conditions compared to single-peak LED. Prevention of errors when curing composites requires the attention of all personnel involved in the patient's care once the clinical relevance of the appropriate polymerization reflects on reliable long-term outcomes.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.5A
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• pp.503-510
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• 2009

Latex modified concrete (LMC) is a successful polymer-portland cement concretes, which have been developed and used for many years, in overlaying bridge decks and resurfacing industrial floors. The excellent bond strength to substrate, easy application and high resistance to impact, abrasion, wear, aggressive chemicals and freeze-thaw deterioration have made this material used widely. The objective of this study was to determine experimentally the load-deflection response and ultimate strength of reinforced RC beams. The cracking patterns and the mode of failure were observed. Because of excellent bond strength and repairing effects, the RC beams repaired by LMC at compression or tension zone showed over 100% recovery from damaged structures. The RC beams overlaid by LMC showed significant improvement at load carrying capacity as overlay thickness increases. However, the beams repaired of tension zone without shear stirrups almost showed no strengthen effect, and indicated an interfacial failures. The interfacial behavior was estimated by numerical method adopting the concept of shear flow.

• Journal of the Korean Society of Food Culture
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• v.25 no.6
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• pp.708-718
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• 2010

This study was conducted to examine the effects of a healthy dietary life and purchase of environmental-friendly food materials according to a mother's lifestyles of health and sustainability (LOHAS) attitudes. The subjects consisted of 295 mothers. The findings are summarized as follows. The mother's LOHAS attitude index averaged 3.39 points out of 5 points. High LOHAS attitude items were "I participate actively in separating the trash collection" (4.16 points), and "I recycle dresses that I do not wear by taking them to the recycling center" (4.08 points). In contrast, LOHAS attitude items for "I do community service activity on the weekend" (2.57 points), and "I try to serve in the local community" (2.63 points) scored very low. A high LOHAS behavior index occurred for mothers who were "resource saving", whereas "social welfare" scored low. Mother's intention to purchase environmental-friendly food materials averaged 3.61 points. Mother's health dietary life attitude score averaged 3.52 points. When age, monthly income, and the environmental-friendly food materials purchase ratio of the mother was high, the health dietary life performance was high. The LOHAS attitude index of mothers had an impact on the purchase intention of environmental-friendly food materials in resource saving and environmental-friendly oriented propensity groups. The LOHAS attitude index of mothers impacted healthy dietary life in environmental-friendly, family and health oriented propensity groups.

• Journal of Fashion Business
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• v.27 no.3
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• pp.1-18
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• 2023

The online shopping industry in China has experienced rapid growth, particularly in the infant goods sector, which is considered highly promising in terms of its growth potential. This growth can be attributed to the Chinese market's increasing economic power, the implementation of new policies concerning marriage and childbirth, changes in family structure, and evolving and diverse consumer demands for infant products. While the infant clothing industry has emerged as a significant player in the Chinese market, there is still a lack of sufficient academic research on the online shopping environment specific to China's infant clothing industry. The objective of this study was to explore the influence of online experiential marketing on brand loyalty and purchase intention among Chinese consumers of children's wear. The study findings indicated that the emotional experience, action experience, and relationship experience encountered by consumers during online interactions had a positive and significant impact on brand loyalty. Both perceptual experience and cognitive experience had a positive and significant influence on consumers' willingness to make a purchase. The study also revealed that brand loyalty had a positive and significant effect on consumers' purchase intention. The perception of online experiential marketing, brand loyalty, and purchase intention varied based on individual attributes, and gender was found to moderate the relationship between online experiential marketing and brand loyalty.

• Geomechanics and Engineering
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• v.31 no.3
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• pp.249-263
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• 2022

The specially-shaped Polycrystalline Diamond Compact (PDC) cutter is widely used in drill bit design due to its advantages of high rock cutting efficiency, strong impact resistance and long service life in hard and abrasive formation drilling. A detailed understanding of rock cutting behavior of worn specially-shaped PDC cutter is essential to improve the drilling efficiency and decrease the drilling costs. In this paper, the theoretical models of two new principles (loading performance (LP) and cutting performance (CP)) are derived for evaluating the cutting process of worn specially-shaped cutter, the theoretical models consider the factors, such as cutter geometry, aggressiveness, stress state, working life, and rock cutting efficiency. Besides, the numerical model of heterogeneous granite is developed using finite element method combined with Voronoi tessellation, the LP and CP of 12 kinds of worn specially-shaped PDC (SPDC) cutters are analyzed. The results found that the mechanical specific energy (MSE) of worn cutters first increase and then decrease with increasing the cutting depth, and the MSE increase with the increase of back rake angle except for Conical cutter and Wedge-shaped cutter. From the perspective of CP, the worn PDC cutters are more suitable for the smaller cutting depths, and the back rake angle has little effect on the CP of the specially-shaped worn PDC cutters. Conical cutter, Saddle-shaped cutter and Ellipse-shaped cutter have the highest CP value, while Rhombus-shaped cutter, Convex cutter and Wedge-shaped cutter have the lowest value in selecting cutters. This research leads to an enhanced understanding of rock-breaking mechanisms of worn SPDC cutters, and provides the basis to select of specially-shaped PDC cutters for the specific target formation.

• Journal of Convergence for Information Technology
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• v.8 no.1
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• pp.131-138
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• 2018

The purpose of the study was to explore whether the Cyber Motion sickness used VR causes a change in the dynamic balance and fall. For 39 people who voluntarily participated in this study, this study measured the motion sickness questionnaires, the heart rate and stability of limit test in BioRescue. The study used Samsung Gear VR and applied the games to the To the homeland. The game proceeded 20minutes. Although the value of the stability after a VR application is slightly reduced, it did not reach statistical significance. The motion sickness questionnaires increased, and it had a statistical significant impact. Also Heart rate increased and it had a statistically significant impact. A virtual reality game affect for getting motion sickness but it did not affect the dynamic balance. So, cyber motion sickness caused by virtual reality wear does not result in decreased balance and falls.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.5 no.1
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• pp.75-80
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• 1999

The Taekwondo being a martial sports, there are higher chances for the injury to occur than the non martial sports. Therefore, this study analyze the frequency, the area, the type, and the condition of the injury which are prone to occur in the Taekwondo matches; it is to help the Taekwondo players in prevention of the injury and in treatment. The subjects of this study were the 48 players (male 24, female 24) who participated in the final selection contest of the national team player on March 9 to 12, 1993. The data of the injury were obtained from the medical recoder staff and were analyzed to the frequency of the injury per match, the vulnerable area of the injury, the type of injury, and the condition of the injury with a gender difference. There were 24 matches for the male and 24 matches for the female, total 48 matches. Therefore, the total participation number of the players are the double of the match number. 1. The frequency of the injury per match was 18.3%(11/60) for male and 23.1%(12/52) for women. 2. The areas of the injury were ankle 36.4%(4), foot 18.2%(2), knee 18.2%(2), lower leg 18.2%(2), wrist 9.1%(1) in male; foot 33.4%(4), ankle 16.7%(2), knee 16.7%(2), lower back 16.7%(2), lower leg 8.3%(1), face 8.3%(1) in female. 3. The types of the injury were contusion 45.5%(5), sprain 27.3%(3), abrasion 9.1%(1), laceration 9.1%(1), tendon rupture 9.1%(1) in male; contusion 33.3%(4), sprain 33.3%(4), abrasion 16.7%(2), subcutaneous hemorrhage 8.3%(1), dislocation 8.3%(1) in female. 4. The condition of the injury were the unblocked attack 36.4%(4), attacking kick 27.3%(3), blocking a kick 18.2%(2), attacking punch 9.1%, impact with surface 9.1%(1) in male; attacking kick 33.3%(4), unblocked attack 25%(3), blocking a kick 25%(3), attacking punch 8.3%(1), impact with surface 8.3%(1) in female. This study shows that the injury from the Taekwondo matches occurred most in the lower extremity joints and the foot, and shows that the most of the injury types were contusion and sprain. Therefore, it is believed to be helpful to wear the proper fitting ankle or the knee protector and using other protective equipment to prevent the sports injury in the Taekwondo matches.

• Journal of Distribution Research
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• v.17 no.2
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• pp.93-115
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• 2012

This study empirically examines the impact of changes in market shares among retailing types on the price index. The retailing type is classified into 6 groups: department store, big mart, super market, convenient store, specialty merchant, and on-line store. The market shares of retailing types are calculated by the ratio of each retailing type monthly sales to total monthly retailing sales in which total retailing sales is the sum of each retailing type sales. We employed several price indices: consumer price index (CPI), CPI for living necessaries, and fresh food price index. In addition, this study used fundamental price indices based on 25 product families as well as 42 representative products. The empirical model also included several variables in order to control for the macroeconomic effects and those variables are the exchange rate, M1, an oil price, and the industrial production index. The data is monthly time-series data spanning over the period from January 2000 to December 2010. In order to test for the stability of data series, we conducted ADF test and PP test in which the model and length of lag were determined by the relevant previous literature and based on the AIC. The empirical results indicate that changes in market shares among retailing types have impacts on the price index. Table A shows that impacts differ as to which price index to use and which product families and products to use. For department store, it lowers the price of food and non-alcoholic beverages, home appliances, fresh food, fresh and vegetables, but it keeps the price high for fresh fruit. The big mart retailing type has a positive impact on the price of food, nut has a negative effect on clothing and foot wear, non-food, and fresh fruit. For super market, it has a positive impact on food and non-alcoholic beverages, fresh food, fresh shellfishes, but increases the price of CPI for living necessaries and non-food. The specialty merchant retailing type increases the price level of CPI for living necessaries and fresh fruit. For on-line store type, it keeps the price high for CPI for living necessaries and non-food as well as fresh fruit. For the analysis based on 25 product families shows that changes in market shares among retailing types also have different effects on the price index. Table B summarizes the different results. The 42 representative product level analysis is summerized in Table C and it indicates that changes in market shares among retailing types have different effects on the price index. The study offers the theoretical and practical implication to these findings and also suggests the direction for the further analysis.