• Journal of Power System Engineering
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• v.13 no.3
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• pp.33-39
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• 2009

The aim of this study is to analyze the welds characteristics of the 205 stainless steel pipe for application of street pole material. The welds corrosion behavior of STS 205 pipe in 0.1 N sulphuric acid solution and 5% NaCl solution at room temperature was studied using both salt spray test and potentiodynamic polarization experiment. The morphology and components of corrosion products on surface of STS 205 pipe welds were investigated using SEM/EDX. The tensile strength and yield strength values of STS 205 plate were 715 MPa and 369 MPa respectively. The microvickers hardness values of STS 205 pipe welds were slightly increased than that of STS 304 pipe welds. Corrosion current density($I_{corr.}$) and critical current density($I_{crit.}$) values of STS 205 pipe welds in 3.5% NaCl solution were $1.89{\times}10^{-6}$ $A/cm^2$ and $15.8{\times}10 ^{-6}$ $A/cm^2$. The corrosion resistance of SIS 205 pipe welds was similar to its STS 304 pipe welds. The STS 205 and 304 pipe welds passive films were chromium oxide. Especially, the STS 205 pipe welds showed good corrosion resistance in 0.1 N sulphuric acid. This is attributed to the forming of protective chromium oxide on the surface of STS 205 pipe welds.

• Radiation Oncology Journal
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• v.30 no.2
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• pp.62-69
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• 2012

Purpose: To evaluate the treatment outcome and prognostic factor of postoperative radiotherapy for extremity soft tissue sarcoma (STS). Materials and Methods: Forty three patients with extremity STS were treated with conservative surgery and postoperative radiotherapy from January 1981 to December 2010 at Korea University Medical Center. Median total 60 Gy (range, 50 to 74.4 Gy) of radiation was delivered and 7 patients were treated with chemotherapy. Results: The median follow-up period was 70 months (range, 5 to 302 months). Twelve patients (27.9%) sustained relapse of their disease. Local recurrence occurred in 3 patients (7.0%) and distant metastases developed in 10 patients (23.3%). The 5-year overall survival (OS) was 69.2% and disease free survival was 67.9%. The 5-year local relapse-free survival was 90.7% and distant relapse-free survival was 73.3%. On univariate analysis, no significant prognostic factors were associated with development of local recurrence. Histologic grade (p = 0.005) and stage (p = 0.02) influenced the development of distant metastases. Histologic grade was unique significant prognostic factor for the OS on univariate and multivariate analysis. Severe acute treatment-related complications, Common Terminology Criteria for Adverse Events (CTCAE) grade 3 or 4, developed in 6 patients (14.0%) and severe late complications in 2 patients (4.7%). Conclusion: Conservative surgery with postoperative radiotherapy achieved a satisfactory rate of local control with acceptable complication rate in extremity STS. Most failures were distant metastases that correlate with tumor grade and stage. The majority of local recurrences developed within the field. Selective dose escalation of radiotherapy or development of effective systemic treatment might be considered.

• Journal of Veterinary Clinics
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• v.41 no.1
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• pp.24-29
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• 2024

A 6-year-old spayed female French Bulldog presented with a left-sided chest wall tumor. Physical examination revealed that the tumor was firmly adhered to the chest wall. A preoperative punch biopsy of the tumor revealed a grade 2 soft tissue sarcoma (STS). On computed tomography, the tumor's dimensions were assessed as 6.5 × 5.7 × 3.5 cm, and it exhibited invasiveness near the tissue surrounding the ninth rib. The tumor size was large in comparison to the dog's chest wall area. Hence, if the traditional wide-margin resection surgery were to be performed, primary wound closure seemed impractical and could potentially result in respiratory function complications. Therefore, considering the extent of tumor invasion and grade, deep margins were established to include the removal of the eighth to tenth ribs, and a 1-cm lateral margin was designated to enable primary wound closure. To reconstruct the chest wall, polypropylene mesh was attached to the adjacent ribs and the remaining muscles were sutured and covered over the mesh. The dog exhibited a rapid recovery beginning the day after the operation. Postoperative biopsy confirmed that the tumor was a grade 2 STS, and the surgical margins were evaluated as incomplete. The owner chose to pursue follow-up observation instead of chemotherapy. In this study, the surgical approach was chosen based on the importance of functional recovery after surgery. Recent research indicates that the tumor grade is more critical for postoperative prognosis than the extent of surgical margins when removing an STS.

• Journal of the Korean Chemical Society
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• v.55 no.4
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• pp.703-714
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• 2011

The purpose of this study was to investigate the effect of STS modules reflecting Ansan's geological characteristics in Chemistry I on high school students' science related attitudes and preference for STS lessons. The subjects were 10th grade students from K High School in Ansan and comprised 71 students in the experiment group and 78 students in the control group from 2 classes each. Pretest-posttest control group design was employed for the purpose of research. Four STS modules with lesson plans and teaching materials with themes of water, air, and energy, all of which are closely related to high school Chemistry I were developed and applied to the experiment group. The science related attitudes and preference for STS lessons were then examined in pre- and post-tests. The science related attitudes of the experiment group were significantly high in three out of five domains compared to the control group who was taught traditionally. The preference for STS lessons of the experiment group were highly positive in all five areas and were particularly high in the area of 'relation to society'. Such results imply that in order to make effective high school Chemistry I curriculum units related to STS, emphasized by both the 7th National Curriculum and the Revised 7th National Curriculum, it is necessary to use episodes reflecting local characteristics in which students show greater interest and active participation.

• Journal of Welding and Joining
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• v.32 no.5
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• pp.80-86
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• 2014

We have successfully fabricated high strengthening Cu/STS/Cu 3 layered clad metal of $70kgf/mm^2$ grade for electric device lead frame, and investigated thermal effect of the mechanical and physical properties on the Cu/STS/Cu 3 layered clad metal lead frame material at different temperatures ranging from RT to $200^{\circ}C$. The fabricated clad metal shows a good thermal stability under 6% degrading of mechanical tensile strength and hardness change at $200^{\circ}C$ and also physical properties show stable thermal and electrical conductance of over $220W/m{\cdot}K$ and 58.44% IACS upto the $200^{\circ}$. The results confirm that fabricated high strengthening Cu/STS/Cu 3 layered clad metal can be applied for the high performed electrical lead frame devices.

• Hwankyungkyoyuk
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• v.19 no.1 s.29
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• pp.14-29
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• 2006

The purpose of this study was to test effect of STS instruction using the subject matter of marine life on middle school students' perception of ocean. The objects of 156 students were sampled from the 1st grade of a middle school and were divided into an experimental group and a control group. 79 students of the control group were treated with traditional instruction, while 77 students of the experimental group were treated with STS instruction materials. All of the students took test of perception of ocean before and after the instructions. The perception of ocean was divided into four categories; value of sea, development of marine resources, research and conservation of sea, and perception of sea-related vocation. The results of the pretest and the posttest indicated that the perception of ocean of the experimental group was statistically significantly higher than that of the control group. Specially in categories of the value of sea and the research and conservation of sea, the scores of the experimental group were significantly higher than those of the control group.

• The Korean Journal of Emergency Medical Services
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• v.13 no.2
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• pp.5-15
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• 2009

Purpose : This study was to examine the secondary traumatic stress(STS) and related factors of emergency medical technicians. Methods : This study was conducted among 190 emergency medical technicians, over the age of 25, with the 1st or 2nd grade qualification, who serve at fire stations in U and P city of Korea. The collected data for this study was analyzed using SPSS 12.0. Result : The average character type of A-type personality technicians was 43.25 points and the average of B-type personality technicians was 37.82 points. It suggested that the former was higher than the latter. State anxiety did not show statistically significant difference between A-Type group and B-Type group with the score of 48.51 for A-Type and 47.91 for B-Type. Physical symptoms showed statistically significant difference between the two groups with the higher score of 28.45 for A-type group than that of 28.13 for B-Type group. The level of STS related to the volunteers' job characteristics was found to be low when the volunteers were satisfied with their job and didn't want to transfer to another division. Those on duty who had slept more than seven hours that day had the highest points. The number of points was highest when the frequency for the onset of trauma was between 20~30 times. Furthermore it was found that for most technicians, 71.05%, the period of symptoms lasted for a few weeks at most, and this was where the STS was the lowest, whereas on the other hand the highest STS occurred when the symptoms lasted for a period of up to six months. The findings showed significant correlations with a relation of r=.24 between STS and level of anxiety and r=.45 between STS and physical symptoms. However, no significant correlation was found between the level of anxiety and physical symptoms. Conclusion : The more emergency medical technicians are exposed to accidents, the more serious the STS are. Those with an A-type personality are especially prone to have higher STS. The higher the STS level is, the higher the level of physical states and anxiety is.

• Journal of the Korea Society of Computer and Information
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• v.29 no.10
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• pp.97-104
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• 2024

This paper proposes a method for classifying the grade of stainless steel using a portable NIR(Near Infrared Ray) spectrometer and a CNN(Convolutional Neural Network) deep learning model. Traditionally, methods for classifying stainless steel grades have included chemical analysis, magnetic testing, molybdenum spot tests, and portable XRF devices. In addition, a classification method using a machine learning model with element concentration and heat treatment temperature as parameters was presented in the paper. However, these methods are limited in their application to everyday products, such as kitchenware and cookware, due to the need for reagents, specialized equipment, or reliance on professional services. To address these limitations, this paper proposes a simple method for classifying the grade of stainless steel using a NIR spectrometer and a CNN model. If the method presented in this paper is installed on a portable device as an on-device in the future, it will be possible to determine the grade of stainless steel used in the product, and to determine on-site whether a product made of low-cost material has been disguised as a high-cost product.

• Journal of The Korean Association For Science Education
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• v.25 no.3
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• pp.327-335
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• 2005

This study investigates student achievement and science-related attitudes on STS hypothetical deductive instruction strategy in the water section of high school chemistry. Two 11th grade co-ed high school classes participated in the study; one control group and one treatment group. After being taught for 10 class periods during the second semester. ANCOVA analysis revealled no significant difference (p>.05) between two groups' achievement tests. However, analysis by ANCOVA did show that the scores for science-related attitudes in the treatment group were significantly higher than those of the control group (p<.05). In particular, the scores of science learning contents and science value about science-related attitude were significantly higher in the treatment group.

• Journal of Korean Elementary Science Education
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• v.33 no.2
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• pp.207-216
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• 2014

Understanding the nature of science (NOS) has been a major component of scientific literacy and an important learning goal in science education (American Association for the Advancement of Science, 1990, 1993; Millar & Osborne, 1998; National Research Council, 1996, 2013). To achieve this goal, it is necessary to include appropriate views of the nature of science in science curriculum such as a textbook. The aim of this study was to conduct a content analysis of the elementary science textbooks to examine the presentation of the nature of science (NOS) using the four themes of scientific literacy, which are (1) nature of scientific knowledge, (2) nature of scientific inquiry, (3) nature of scientific thinking, and (4) nature of interactions among science, technology, and society (STS). Findings show while $3^{rd}$ and $4^{th}$ grade levels of science textbooks heavily emphasize on the Theme I, nature of scientific knowledge and the Theme II, the nature of scientific inquiry, the upper grade levels such as $5^{th}$ and $6^{th}$ grades of science textbooks are well balanced with the four themes of the nature of science. In addition, most of elementary science textbooks little focus on the Theme IV, nature of interactions among science, technology, and society (STS) among the four themes of the nature of science. It might be a shortcoming because the understanding the nature of interacions among science, technology and society (STS) is one of the key components in order for students to be a scientific literate person.