• Steel and Composite Structures
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• v.53 no.2
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• pp.243-252
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• 2024

Conventional carbon mild steel is a type of steel known for its low carbon content and generally used in the construction industry. Its easily formable and weldable properties make this steel a widely preferred material for buildings, bridges and various construction projects. Other advantages of these steels are their low cost and good mechanical properties. However, high temperatures have an impact on the microstructure and mechanical characteristics of these materials. When high temperatures are present during a fire, steels show significant microstructural changes. Elevated temperatures often decrease the mechanical characteristics of steels. For this purpose, evaluating the post-fire behavior of conventional structural mild steel is an important issue in terms of safety. A combined experimental and parametric study was conducted to estimate fire damage to steel buildings, which is an important issue in the construction field. Tensile test coupons were cut from conventional structural S235JR mild steel sheets with thicknesses ranging from 6 mm to 12 mm. These samples were exposed to temperatures as high as 1200 ℃. After heat treatment, the specimens were allowed to naturally cool to ambient temperature using air cooling before being tested. A tensile test was performed on these coupons to evaluate their mechanical properties after fire, such as their elastic modulus, yield strength, and ultimate tensile strength. The mechanical behavior of conventional S235JR structural steel changed significantly when the heating temperature reached 600℃. The thickness of the steel had a negligible effect on yield strength loss, with the highest measured loss being 50% for 8 mm thickness at 1200℃. For thinner sections (6 mm), yield strength decreased by up to 40%, while thicker samples (12 mm) showed similar reductions. Ultimate tensile strength also showed minimal changes up to 600℃, but beyond this point, a notable decline occurred, with approximately 30% strength loss at 1200℃. The modulus of elasticity remained almost constant up to 800℃, but at 1200℃, the loss reached around 20% for thicker sections (10 mm and 12 mm) and up to 35% for thinner sections (6 mm and 8 mm). Overall, high temperatures led to significant deterioration in both yield and ultimate strength, with a general loss of load-bearing capacity above 600℃. A new equation was formulated from experimental results to predict changes in the mechanical properties of S235JR steels. This equation offers a precise evaluation of buildings made from conventional structural S235JR mild steel after fire exposure. Furthermore, the empirical equation is applicable to low-strength steels with yield strengths ranging from 235 MPa to 420 MPa.

• Journal of Korean Public Health Nursing
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• v.29 no.1
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• pp.40-52
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• 2015

Purpose: This study examined the characteristics of preparation to perform activities of suicide prevention according to professional type. Methods: A structural survey was conducted from Dec. 10, 2012 to Jan. 4, 2013 for 355 participants working at suicide prevention institutions in S city. The data were analyzed in terms of frequency, percentage, mean, standard deviation, t-test, ANOVA, Pearson's correlation coefficient, and multiple regression using SPSS/WIN 18.0. Results: Self-evaluation knowledge of characteristics was a significant distance depending on education and economic status. Participants were classified according to four groups based on professional type; public health nurse, social worker, fire officer, and administrative staff. Significant differences in experiences in suicide, the several items of self-evaluation knowledge, and the preparation to perform activities of suicide prevention were observed according to professional type (p<.05). Correlation among the experience, self-evaluation knowledge and preparation to perform activities of suicide prevention showed a positive correlation in public health nurse, social worker, and administrative staff (p<.05). In all professional types, the variable that predicted preparation to perform activities of suicide prevention was self-evaluation knowledge (p<.001). Conclusion: Tailor-made suicide prevention programs that affect changes in preparation to perform activities of suicide prevention should be developed by professional types.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.9_10 s.157
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• pp.1400-1412
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• 2006

As PB market segments into premium market, PBs were drawing attentions in terms of creating profits as well as a means to differentiate building up store identity. The purpose of this study makes a comparative study on the difference of consumer attitude formation process in discount store and home-shopping distribution channel which are recently on the upswing. This paper investigated the consumer's attitude formation on the private apparel brand. Subjects of this study were consumers in their $20s{\sim}40s$ who are main customer groups of PBs. The data were analyzed by Structural Equation Modeling and Multi-Group Analysis of Amos 5.0 to verify the difference of the path between store PB and premium PB. Following are the results of the study. Consumer attitude formation path on PB grades showed statistically noticeable difference. In discount store PB, store evaluation didn't directly influence on consumer attitude formation but showed indirect effect. On the other hand, in home shopping premium PB case, product evaluation directly influenced on consumer attitudes with store evaluation. Hedonic attitude dimension connected with behavioral attitude(purchase intention) revealed difference in path. Also consumer's evaluation on variables in model turned out to be different according to brand grade.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.12
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• pp.1871-1876
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• 2010

The reduction of vehicle interior noise has been the main interest of NVH engineers. The driver's perception of the vehicle noise is strongly affected by the psychoacoustic characteristics of the noise and the SPL. The existing methods to evaluate the SQ for vehicle interior noise are linear regression analysis of subjective SQ metrics by statistics and the estimation of subjective SQ values by neural network. However, these methods strongly depend on jury tests, this leads to difficulties. To reduce the important of the jury tests, we suggest a new method using the Mahalanobis distance for SQ evaluation. And, the optimal characteristic values that influenced the results of sound quality evaluation on the basis by main effect. Finally, we developed a new method based on the MD method to evaluate sound quality. The result of noise evaluation revealed that the sound quality could be well improved by changing the structural characteristics of the vehicle.

• Journal of Distribution Science
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• v.16 no.4
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• pp.75-82
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• 2018

Purpose - As the role of salespersons in retail stores has expanded from selling products to sharing brand experiences with customers, the importance of research on the effects of salesperson-brand relationships has grown. The purpose of this research is to investigate the influences of salespersons' brand identification on conceptual fluency and customers' service and brand evaluations. It was supposed that salespersons' brand identification is affected by brand knowledge, which is a core dimension of internal branding. Research design, data, and methodology - The author developed a structural model in which salespersons' brand knowledge influences brand identification, hence customers' perception of salesperson-brand image congruence. And it is hypothesized that salesperson-brand image congruence influences conceptual fluency which affects customers' satisfaction and brand evaluation. Data were collected from five department stores in Seoul. Results - First, salespersons' brand knowledge was found to have a significant effect on brand identification. The more a salesperson knows about the affiliated brand, the higher her level of brand identification. Second, salespersons' brand identification influenced salesperson-brand image congruence. Third, salesperson-brand image congruence had a significant effect on brand conceptual fluency. Customers who perceive salesperson-brand image congruent are more likely to process information easily. Finally, conceptual fluency was found to be a significant determinant of store loyalty and brand value evaluation. Conclusions - The results of this study verify importance of salesperson's brand identification on customers' service and brand evaluations. To enhance salespersons' brand identification, retailers should emphasize the importance of internal branding and communication, especially by sharing brand vision, values, and identity with employees at customer contact points. Also, as brand conceptual fluency is a significant determinant of customer responses, retailers need to deliver consistent messages through various components of store environments, including salespersons' attitudes, appearances, and manners, as well as physical store design. With a deeper understanding of the effects of salesperson-brand relationship and brand conceptual fluency, retailers will be able to create more effective brand strategies to enhance their performances. Future studies should consider data from various retail types, such as discount stores, to generalize the findings.

• Korean Journal of Child Studies
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• v.25 no.4
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• pp.115-128
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• 2004

In this study, we examined the relationship among Multiple Intelligence constructs and the relationship among the sub-areas and analysed the development of the Multiple Intelligence according to age and gender to evaluate Korean children's Multiple Intelligence structures that teachers evaluated based on MIDAS-MYC. The subjects of the study consisted of 158 4-5 year old children (71 4-year-old group(boy 38, girl 33); 87 5-year-old group(boy 40, girl 47)) in Seoul and Gyeonggi. We found several results which are as follows. 1) Reliability on each area of intelligence in MIDAS-MYC was good. 2) The result of confirmatory factor analysis using the model of structural equation modeling was consistent with the results of other studies that children's Multiple Intelligence consists of eight intelligent areas that are independent to each other but are relative to each other. In particular, interpersonal-intrapersonal intelligence, languistic-intrapersonal intelligence, languistic-Interpersonal intelligence, and languistic-logic/math intelligence were high correlation. However, physical/motion-naturalist intelligence and musical-logic/math intelligence were low correlation. 3) Children's multiple intelligence differed according to age and sex, the 5-year-old was higher than 4-year-old and girls were higher than boys in a general way. 4) There was high correlation between the result of evaluation based on MIDAS-MYC and the result of teacher's subjective evaluation about children's Multiple Intelligence.

• Journal of the Korean Geotechnical Society
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• v.30 no.4
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• pp.81-92
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• 2014

The integrity evaluation of river levee includes slope stability evaluation of riverside land and protected low-land, and safety of piping with respect to critical gradient and critical velocity based on related regulations, such as Design Criteria Rivers Commentary (2009), Structural Design Criteria Based Commentary (2009). The design hydro-graph is the most important design input factor for the integrity evaluation; it can be inaccurate due to the absence of its decision methods suggested by the national level. The authors in this paper evaluated numerical analytic levee integrity for piping and slope stability by changing each design hydro-graph, including rising ordinary water level, lasting flood water level, falling water level, and flood frequency for Mun-san-jae on Nak-dong River. Finally, the authors suggested that the levee integrity of piping and slope stability are very sensitive to the changes of increasing time of ordinary water level by 57 hours and lasting time of the flood water level by 53 hours, respectively, for Mun-san-jae.

• The Journal of Korean Physical Therapy
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• v.25 no.2
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• pp.76-80
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• 2013

Purpose: The objective of this study was to offer primary clinical data examining whether change of imaging structure and quantitative evaluation of muscle activity on myofascial trigger points can lead to implementation of an analytical technique for evaluation of myofascial pain diagnoses. In addition, we examined the effect of a variety of mediation techniques, in order to examine neuromuscular physiological characteristics of myofascial trigger points muscle by comparing differences in pressure pain threshold and ultrasound imaging. Methods: Participants in the study included 30 adults in their twenties. The subjects were divided into the normal and myofascial trigger points groups. Clinical outcomes were evaluated by pressure pain threshold for pain and ultrasound imaging was performed for evaluation of the structural characteristics of muscle. Independent t-test was used for statistical analysis. Results: The two groups showed statistical significance in the change in pressure pain threshold (p<0.05). Findings of ultrasound imaging analysis showed no significant differences, increased muscle thickness was observed (p>0.05). Findings of ultrasound imaging analysis showed significant differences, increased muscle echodensity was observed (p<0.05). Findings on ultrasound imaging analysis showed significant differences, increased muscle white area index was observed (p<0.05). Conclusion: From these results, active myofascial trigger points muscle showed quality deterioration on ultrasound imaging. Thorough evaluation of imaging structure and physiological characteristics can be useful quantitative analytical techniques for diagnosis of myofascial pain syndrome and a primary factor reflected in physical therapy intervention.

• Journal of Advanced Navigation Technology
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• v.19 no.4
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• pp.338-344
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• 2015

The national competency standards (NCS) is a systematize and standardize for skills required to perform their job. The NCS has developed a learning module with materialization and standardize by competence unit element, which is the unit of specific job competency. The existing curriculum is material to gab analysis for use in education training with competence unit element. The existing gab analysis has evaluated subjectively by experts. The gab analysis by experts bring up a subject subjective decision, accuracy lack, temporal and spatial inefficiency by psychological factor. This paper is proposed automated evaluation model for problem resolve of subjective evaluation. This paper use index term extraction, term frequency-inverse document frequency for feature value extraction, cosine similarity algorithm for gab analysis between existing curriculum and competence unit element. This paper was presented similarity mapping table between existing curriculum and competence unit element. The evaluation model in this paper should be complemented by an improved algorithm from the structural characteristics and speed.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.13 no.2
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• pp.1-18
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• 2017

Metal fatigue is an important aging mechanism that material characteristics can be deteriorated when even a small load is applied repeatedly. An accurate fatigue evaluation is very important for component structural integrity and reliability. In the design stage of a nuclear power plant, the fatigue evaluations of the Class 1 components have to be performed. However, operating experience shows that the design evaluation can be very conservative due to conservatism in the transient severity and number of occurrence. Therefore, the fatigue monitoring system has been considered as a practical mean to ensure safe operation of the nuclear power plants. The fatigue monitoring system can quantify accumulated fatigue damage up to date for various plant conditions. The purpose of this paper is to describe the fatigue monitoring procedure and to introduce the fatigue monitoring program developed by the authors. The feasibility of the fatigue monitoring program is demonstrated by comparing with the actual operating data and finite element analysis results.