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A study on the difference in management performance according to the quality management system introduction level of small and medium-sized manufacturing companies (중소제조기업의 품질경영시스템 도입 수준에 따른 경영성과 차이 연구)

  • Lee, JuYong;Joo, HyungKun
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.18 no.2
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    • pp.61-75
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    • 2022
  • The purpose of this study is to analyze the impact of quality management system requirements, a management innovation technique, on business performance to secure the competitiveness of SMEs in an environment of increasing uncertainty in the global economy and intensifying competition. To this end, a survey was conducted on small and medium-sized enterprises (SMEs) operating a quality management system, and statistical analysis was performed through validity and reliability analysis, regression analysis, and group analysis using IBM SPSS 26.0. As a result of the study, it was found that planning, operation, support, and improvement, which are the core requirements of a quality management system, have a positive effect on business performance. In addition, through group analysis, it was found that the effect of quality management system requirements on business performance varies according to the level of the company. This means that the importance of quality management requirements required for strategy establishment varies according to the quality management introduction level of small and medium-sized manufacturers, and it can be used for small and medium-sized manufacturers to set strategic directions.

On the equivalence of reaction rate in energy collapsing of fast reactor code SARAX

  • Xiao, Bowen;Wei, Linfang;Zheng, Youqi;Zhang, Bin;Wu, Hongchun
    • Nuclear Engineering and Technology
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    • v.53 no.3
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    • pp.732-740
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    • 2021
  • Scattering resonance of medium mass nuclides leads complex spectrum in the fast reactor, which requires thousands of energy groups in the spectrum calculation. When the broad-group cross sections are collapsed, reaction rate cannot be completely conserved. To eliminate the error from energy collapsing, the Super-homogenization method in energy collapsing (ESPH) was employed in the fast reactor code SARAX. An ESPH factor was derived based on the ESPH-corrected SN transport equation. By applying the factor in problems with reflective boundary condition, both the effective multiplication factor and reaction rate were conserved. The fixed-source iteration was used to ensure the stability of ESPH iteration. However, in the energy collapsing process of SARAX, the vacuum boundary condition was adopted, which was necessary for fast reactors with strong heterogeneity. To further reduce the error caused by leakage, an additional conservation factor was proposed to correct the neutron current in energy collapsing. To evaluate the performance of ESPH with conservation factor, numerical benchmarks of fast reactors were calculated. The results of broad-group calculation agreed well with the direct full-core Monte-Carlo calculation, including the effective multiplication factor, radial power distribution, total control rod worth and sodium void worth.

Composite effects of circular concrete-filled steel tube columns under lateral shear load

  • Faxing Ding;Changbin Liao;Chang He;Wei Gao;Liping Wang;Fei Lyu;Yuanguang Qiu;Jianjun Yang
    • Computers and Concrete
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    • v.31 no.2
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    • pp.123-137
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    • 2023
  • To fully understand shear mechanisms and composite effects of circular concrete-filled steel tube (CFST) columns, systematic numerical investigations were conducted in this paper by improved finite element models. The triaxial plastic-damage constitutive model of the concrete and the interactions between the concrete and steel tube were considered. Afterwards, the critical and upper bound shear span ratios of the circular CFST column under lateral shear loading were determined. The composite effects between the two materials were analyzed by comparing the shear resistance with plain concrete column and hollow steel tube. In addition, a method that predicts the shear bearing capacity of a circular CFST column was proposed. The confining effects on the concrete core and the restraining effects on the steel tube were considered in this method. The proposed formula can predict more accurate results than the methods in different codes and references.

Transformable eco-friendly one-touch DIY children's furniture for childr en's growth and development

  • JEON, Jin-Soo;KIM, Hyun-Joo;Han, Sul-A
    • Archives of design research
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    • v.25 no.5
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    • pp.113-119
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    • 2012
  • Under the paradigm of 'Eco', the core of sustainability management, this study aims to establish both domestic and international markets and secure competitiveness in the global markets through the development of children's furniture composed of recycled and unharmful materials. Currently, in Europe and in the Western regions, the concepts of 'eco-friendly', 'children', and 'DIY' are well-placed in the daily lives of the people. On the other hand, compared to the domestic demand for eco-friendly children's furniture, the essential approach and the qualitative improvements about the subject are being slowly progressed. Particularly, the process of applying eco-friendly materials and finishing materials to the children's furnitures are mostly in a non-existent state. Thus, in this study, simple application of basic eco-friendly materials such as natural woods or imitation of overseas furniture designs were avoided to create transformable eco-friendly one-touch DIY children's furniture for children's growth and development through the application of eco-friendly processes of technology, design, and other stages of the development process. In other words, under the big category of eco-friendly children's furniture, the furniture was developed through an environmentally-friendly process of universal design that is suitable for children of all ages, and thus, ultimately maximizing the economical effective value and reducing consumption of resources and environmental pollutions.

Study on Qiang embroidery patterns creative design based on Shape Grammars

  • Ruiyu Li;Xiajie Zhao
    • International Journal of Advanced Culture Technology
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    • v.12 no.1
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    • pp.51-59
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    • 2024
  • Qiang ethnic group is one of the fifty-six ethnic minorities in China, and Qiang embroidery, as an important achievement of Qiang's intangible cultural heritage, is the precipitation and testimony of the history and culture of the Qiang ethnic group. However, with the development of the times, traditional and ancient Qiang embroidery is facing a dilemma due to the problem of a single form of communication. Therefore, it is necessary to add new communication media for Qiang embroidery to help it spread and develop better. In this paper, we extract the core representative patterns of Qiang embroidery, use the "shape grammars" as the rules of morphological changes, and generate new decorative pattern patterns with the characteristics of Qiang embroidery by adding, deleting, mirroring, rotating, and other relevant rules of changes, and combine the new patterns with the rules of formal beauty to combine the layout, which is then applied in the design of different cultural creations and products. The new patterns are combined with the rules of formal beauty and applied in the design of different cultural and creative products. To provide a quantitative method for the digital protection of Qiang embroidery in the new era of Chinese traditional art, and also provide new ideas for the industrialization application.

Development and validation of transient analysis module in nodal diffusion code RAST-V with Kalinin-3 coolant transient benchmark

  • Jaerim Jang;Deokjung Lee
    • Nuclear Engineering and Technology
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    • v.56 no.6
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    • pp.2163-2173
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    • 2024
  • This study introduces a transient analysis module developed for RAST-V and validates it using the Kalinin-3 benchmark problem. For the benchmark analysis, RAST-V standalone and STREAM/RAST-V calculations were performed. STREAM supplies the few-group constants and RAST-V conducts a 3D core simulation utilizing few-group cross-sectional data. To improve accuracy, the main solver was developed based on the advanced semi-analytic nodal method. To evaluate the computational capability of the transient analysis module in RAST-V, Kalinin-3 benchmark is employed. Kalinin-3 represents a coolant transient benchmark that offers experimental data during the deactivation of the Main Circulation Pumps. Consequently, the transient calculations reflected the changes in the reactor flow rate. Benchmark comprising steady-state and transient calculations. During the steady state, the STREAM/RAST-V combination demonstrated a 30 ppm root mean square difference from 0 to 128.50 EFPD. For the transient calculations, STREAM/RAST-V showed power differences within ±7 % over a range of 0-300 s. Axial offset differences were within ±3 %, and the RMS difference in radial power ranged within 2.596 % at both 0 and 300 s. Overall, this study effectively demonstrated the newly developed transient solver in RAST-V and validated it using the Kalinin-3 benchmark problem.

Measuring stress responses using active biotelemetry in cattle II. Fluid administration for reducing transport stress (Active biotelemetry를 이용한 젖소의 스트레스 반응 측정: II. 수송 스트레스 감소를 위한 수액투여 효과)

  • Lee, Su-han;Lee, Byeong-han;Lim, Joa-jin;Kim, Jin-young;Lee, Dong-hee;Kim, Jae-kyung;Choe, Nong-hoon;Jeong, Soon-wuk;Chung, Byung-hyun
    • Korean Journal of Veterinary Research
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    • v.41 no.4
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    • pp.603-609
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    • 2001
  • A transport stress is one of the main causes of economic losses and physiological dysfunction. The present study has been performed to suggest a method to decrease the adverse effects above mentioned from transport. The groups were prepared as follows; (1) Control group : 4 cattle transported for 5 hrs (274 km) without any treatment, (2) Treatment group : 4 cattle treated with electrolyte-mineral solution (I.V.) at 1 hr before the enrollment of transport under same experimental condition with Control group. The blood specimens were collected at 1 hr before transport, 2.3 hrs (135 km) and 5 hrs (274 km) after the enrollment of transport, and 1, 6 and 18 hrs after fulfillment of transport. The collected blood specimens were analyzed for cortisol and epinephrine. Core temperature and heart rate were measured with active biotelemetry in every 30 minutes from 0.5 hr before the start of transport to 18 hrs after the end of transport. In results, the level of cortisol considerably increased to the peak either in Control group ($5.3{\pm}1.3{\mu}g/d{\ell}$) and in Treatment group ($4.0{\pm}2.6{\mu}g/d{\ell}$) at 2.3 hrs in transport. The concentration of epinephrine of Treatment group had been higher than that of Control group from the start of transport to 18 hrs after the fulfillment of transport. Particularly there was the biggest gap between Control and Treatment groups, $424.0{\pm}194.1pg/m{\ell}$ and $209.1{\pm}65.1pg/m{\ell}$ respectively, at 6 hrs after the end of transport. The heart rates were considerably increased either in Control group ($81.5{\pm}18.5$ to $126.3{\pm}7.8beats/min$) and in Treatment group ($114.3{\pm}14.4$ to $140.8{\pm}22.4beats/min$) with the enrollment of transport. These results indicate that the concentration of cortisol and the heart rate were pertinent to cognitive parameters to evaluate physiological responses against stress such as transport. In addition, the intravenous administration of electrolyte-mineral solution could be suggested as the method to decrease the adverse effects from a transport stress.

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Effects on Bond Strength between Zirconia and Porcelain according to Etching Treatment and Low Temperature Degradation (지르코니아 표면에칭처리와 저온열화현상이 지르코니아와 전장도재의 결합강도에 미치는 영향)

  • Park, Jin-Young;Kim, Jae-Hong;Kim, Woong-Chul;Kim, Ji-Hwan;Kim, Hae-Young
    • Journal of dental hygiene science
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    • v.14 no.2
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    • pp.140-149
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    • 2014
  • The purpose of this study was to investigate the influence of etching surface treatment and aging treatment of zirconia on the shear bond strength between zirconia core and veneered ceramic. Four groups of zirconia-ceramic specimens were prepared; 1) NEZ group (no etching zirconia), 2) EZ group (etching zirconia), 3) ANEZ group (aging and no etching zirconia), 4) AEZ group (aging and etching zirconia). The shear bond strength between zirconia and porcelain was measured using Instron Universal Testing Machine. Surface texture with crystalline structure of zirconia surface was examined by the field emission scanning electron microscopy (FE-SEM) with ingredient analysis. The fractured surfaces of specimens were examined to determine the failure pattern by a digital microscope. The mean${\pm}$standard deviation of shear bond strengths were $23.47{\pm}3.47$ Mpa in NEZ, $28.30{\pm}4.34$ Mpa in EZ, $21.85{\pm}4.65$ Mpa in ANEZ, $24.65{\pm}3.65$ Mpa in AEZ group, respectively, and were significantly different (p<0.05). The average shear bond strength was largest in EZ group, followed by AEZ, NEZ, and ANEZ groups. Most specimens in NEZ group showed adhesive failure and most specimens in EZ, AEZ, and ANEZ group showed mixed failure. Surface of etching treatment group (EZ and AEZ) showed complex micro-structure and irregular surface texture which may facilitate mechanical interlocking, while untreated zirconia surface presented simpler micro-structure. In conclusion, an etching treatment improved bonding strength between zirconia and porcelain by forming mechanical interlocking.

Qualitative Inquiry on Ways to Improve Science Instruction and Assessment for Raising High School Students' Positive Experiences on Science (고등학생의 과학긍정경험 향상을 위한 교수학습 및 평가 개선 방안에 대한 질적 탐구)

  • Kwak, Youngsun;Shin, Youngjoon;Kang, Hunsik;Lee, Sunghee;Lee, Il;Lee, Soo-Young;Ha, Jihoon
    • Journal of The Korean Association For Science Education
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    • v.40 no.3
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    • pp.337-346
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    • 2020
  • In this study, we investigated the characteristics of students participating in Science Core high schools classes and their relevance to Positive Experiences on Science (hereinafter, PES), and factors causing PES, presented by the students of Science Core high schools. A total of 20 students and five teachers in four regions across the country participated in the in-depth interview, which were conducted with the focus group of students first, and then in-depth interviews with teachers. Based on the interview results, we explored teaching and learning experiences helpful to the PES, assessment experiences resulting in the PES, and ways to support Science Core high schools to enhance their PES. Students and teachers of Science Core high schools argued that students' participation will increase only if they engage in classes while drawing attention within the range that students can understand, students' PES such as scientific interest can be improved through experiments in which students choose topics or design their own exploration process, science competencies such as science problem solving ability and scientific thinking ability should be developed through exploratory experiment activities that fit the nature of science, etc. In addition, regarding ways to improve and support Science Core high schools to enhance PES, securing science class hours, restructuring the contents of science elective courses, and necessity of maintaining Science Core high schools are suggested. Based on the research results of science high school students' PES, ways to improve the PES of general high school students are discussed.

Blend Characteristics of PBT, Nylon6,12 and Preparation of PBT/Nylon6,12 Micro Fiber with Core/shell Structure and their Extrusion Conditions (PBT와 Nylon6,12의 블렌드 특성과 core/shell 구조를 갖는 PBT/Nylon6,12 미세모의 제조 및 압출조건)

  • Park, Hui-Man;Lee, Seon-Ho;Kwak, Noh-Seok;Hwang, Chi Won;Park, Sung-Gyu;Hwang, Taek Sung
    • Korean Chemical Engineering Research
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    • v.50 no.6
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    • pp.1068-1075
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    • 2012
  • Poly(butylene terephthalate) (PBT)/Nylon6,12 core/shell micro fiber were prepared by extrusion molding. To investigate their optimum extrusion conditions, compatibility of PBT/Nylon6,12 blend micro fiber in conformity to their weight ratio and manufacture temperature was explored with SEM morphology and DSC. The alterations in their mechanical properties by extrusion speed were compared and analyzed through a UTM. In comparison with SEM figures, the domain sizes of Nylon6,12 were gradually declined by increasing the extrusion temperature of blends. Furthermore, according to these SEM images, the phase separation between Nylon6,12 domain and PBT matrix became indistinct with increasing of weight percentage of Nylon6,12. In case of DSC, the boundaries of two peaks were almost disappeared when increasing the extrusion temperature and also intervals of each two melting peaks became narrow as increasing the Nylon6,12 ratio. The mechanical properties including tensile strength, elongation, flexural strength and flexural modulus were increased as the increase in the extrusion temperature until $260^{\circ}C$. However, the mechanical properties were actually deteriorated over $260^{\circ}C$. The tensile strength, elongation, flexural strength and flexural modulus at $260^{\circ}C$ were 560 $kg_f/cm^2$, 220%, 807 $kg_f/cm^2$ and 22,146 $kg_f/cm^2$, respectively. These values are more than intermediate values of mechanical properties of PBT and Nylon6,12. These results mean that there is compatibility between PBT and Nylon6,12. Based on the extrusion conditions that produced optimum compatibility of blend, as a result, our group obtained micro fibers with the core/shell structure.