• Journal of The Korean Association For Science Education
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• v.32 no.10
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• pp.1502-1523
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• 2012

Recently, there have been growing interest in teachers' professional development since teachers were regarded as a critical factor in the context of the reform efforts. Along with these efforts, educational researchers have continued to implement various programs to improve teachers' subject matter knowledge, beliefs, and their practices. Although considerable researches have been done regarding the efficiency of these programs, most of them have focused on individual teacher's change. However, a "teacher's mind is socially formed" (Edwards, 2001). This perspective indicates that teacher change is necessarily viewed in terms of social mediational process between individual and the social context. This study examines the interactions between teachers and researchers in order to explore the mediational processes and the aspects of collective understanding, which has emerged from the collaborative workshop. The data were collected from small group activities in a workshop and then analyzed using interactional sociolinguistic approach. Futhermore, activity system was employed to describe the social mediational process. The findings show that participating teachers constructed knowledge through conflict regarding collective understanding. This process of collective understanding was mediated by object, rules, and roles within each activity system. Findings from the study suggest that the sociocultural perspectives to teacher education are essential in understanding how teachers learn to teach and that teachers' professional discourse can play a significant role in teachers' professional development.

• Journal of Korean Society of Archives and Records Management
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• v.11 no.1
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• pp.139-159
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• 2011

This study investigated the perceived significance of laboratory(lab) notebooks and the creation and maintenance of them from the perspectives of graduate students and professors in science fields. Semi-structured interviews of three professors and four graduate students were conducted. The interviewees were from three university laboratories of physics, chemistry and biological science. While professors perceived administrative continuity to be a reason for creating lab notebooks, students valued lab notebooks as a memory, and emphasized learning professional knowledge and skills through the recordkeeping practice. Students understood the ownership of lab notebooks and professors wanted to keep lab notebooks until they retire. Interviewees focused more on the content of lab notebooks rather than the form and the structure. They were also not willing to adopt an electronic lab notebook system. Students learned how to create lab notebooks through a course, their current or former academic advisors, seniors in the lab or well-written sample lab notebooks. In particular, students have learned how to create lab notebooks within their laboratories, which are considered to be communities of practice. In this sense, professors responsible for managing laboratories play an important part in teaching students the recordkeeping practice. University archives should also be more concerned with managing and preserving lab notebooks created from their universities.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.3
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• pp.229-234
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• 1982

Environmental factors are known in general to influence much on the development of abscission layer and thereby on shedding of plant parts. The present study was carried out to determine the effect of meterological condition during ripening on the grain shatterability of rice plants at harvest. Different meteorological conditions were obtained by shifting transplanting timing of 40 days old rice seedlings 4 times with a 15 days-interval. Grain shatterability was measured as tensile strength of rice grains: it varied within a range of 214g. to 251g. in a practically non-shattering Japonica variety'Jinheung' and l27.5g. to 204g. in an easy shattering Indica \times Japonica progeny variety'Taeback'. In view of field loss of rice, the variation in tensile strength with time of transplanting and harvest did not matter in Jinheung, but was an important factor in Taeback. In Taeback the tensile strength was significantly correlated positively with mean, maximum and minimum air temperature and relative humidity during a certain period of grain ripening, especially during 30 days period before harvest, but diurnal range of air temperature showed a significant, negative correlation with it. The tensile strength seemed to be more closely related with min. air temperature than max. air temperature, and it was not significantly correlated with radiation amount during any period of pre-harvest. Meteorological effect on grain shatterability may vary with variety, but temperature regime during ripening appears to play major role among the meteorological factors in easy shattering and more thermophilic Indica \times Japonica varieties: lower the temperature, greater the shatterability.

• Journal of Korean Society of Transportation
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• v.23 no.1
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• pp.103-114
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• 2005

The transit fare resulted from the renovation of public transit system in Seoul is basically determined based on the distance-based fare policy (DFP). In DFP, the total fare a passenger has to pay for is calculated by the basic-transfer-premium fare decision rule. The fixed amount of the basic fare is first imposed when a passenger get on a mode and it lasts within the basic travel distance. The transfer fare is additionally imposed when a passenger switches from one mode to another and the fare of the latter mode is higher than the former. The premium fare is also another and the fare of the latter begins to exceed the basic travel distance and increases at the proportion of the premium fare distance. The purpose of this study is to propose an algorithm for finding K number of paths, paths that are sequentially sorted based on total amount of transit fare, under DFP of the idstance-based fare policy. For this purpose, the link mode expansion technique is proposed in order to save notations associated with the travel modes. Thus the existing K shortest path algorithms adaptable for uni-modal network analysis are applicable to the analysis for inter-modal transportation networks. An optimality condition for finding the K shortest fare routes is derived and a corresponding algorithms is developed. The case studies demonstrate that the proposed algorithm may play an important role to provide diverse public transit information considering fare, travel distance, travel time, and number of transfer.

• Journal of Korean Philosophical Society
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• v.143
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• pp.215-244
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• 2017

It is said that we live in an age of technology. And indeed, science and technology do play key roles to our life of happiness, but they are equally central in all events that threaten it. Science and technology are the means we often turn to in seeking solutions to our problems, and in turn are often the apparent sources of new problems. Thus it is not surprising that they have two aspects at the same time. CCTV has been presented to us as a technical solution to security problems. With the help of CCTV, we can more effectively prevent, detect, and prosecute crimes. With the help of CCTV, both public and private spaces can be made more secure. But of course, CCTV also has a down side. The down side most prominently anticipated has been loss of privacy and proliferation of surveillance. It is largely this potential problem with CCTV that has been regulated against. It is said that one reason for imposing a limitation on individual privacy is the societal interest in the prevention of crime. Accordingly a balance between the need to prevent crime through the use of CCTV and the duty to respect the privacy interests of individual citizens is in need of redress. In other hand, two theories of socio-political philosophy may have provided useful ways of understanding the role of CCTV in contemporary society. Firstly, neo-Marxist frameworks, for instance, stress the use of CCTV to police existing unequal socioeconomic divisions within society and the dominance of particular forms of order based upon materialist agendas. Secondly, Foucauldian frameworks contend that Foucault's notion of panoptic surveillance underpinning (self) disciplinary society is an appropriate template for understanding CCTV in late-modern society. In order to find a new point of valance between security and privacy in the use of CCTV, the participation of each citizen in the discourse to make the new norm is necessary. And to prevent its political misuse, their surveillance, or check for the potential surveillance-power is required.

• Animal Bioscience
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• v.37 no.6
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• pp.1096-1109
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• 2024

Objective: This research aims to explore the nutritional and bioactive peptide properties of goat meat taken from various primal cuts, including the breast, shoulder, rib, loin, and leg, to produce these bioactive peptides during in vitro gastrointestinal (GI) digestion and absorption. Methods: The goat meat from various primal cuts was obtained from Boer goats with an average carcass weight of 30±2 kg. The meat was collected within 3 h after slaughter and was stored at -80℃ until analysis. A comprehensive assessment encompassed various aspects, including the chemical composition, cooking properties, in vitro GI digestion, bioactive characteristics, and the bioavailability of the resulting peptides. Results: The findings indicate that the loin muscles contain the highest protein and essential amino acid composition. When the meats were cooked at 70℃ for 30 min, they exhibited distinct protein compositions and quantities in the sodium dodecyl sulfate-polyacrylamide gel electrophoresis profile, suggesting they served as different protein substrates during GI digestion. Subsequent in vitro simulated GI digestion revealed that the cooked shoulder and loin underwent the most significant hydrolysis during the intestinal phase, resulting in the strongest angiotensin-converting enzyme (ACE) and dipeptidyl peptidase-IV (DPP-IV) inhibition. Following in vitro GI peptide absorption using a Caco-2 cell monolayer, the GI peptide derived from the cooked loin demonstrated greater bioavailability and a higher degree of ACE and DPP-IV inhibition than the shoulder peptide. Conclusion: This study highlights the potential of goat meat, particularly cooked loin, as a functional meat source for protein, essential amino acids, and bioactive peptides during GI digestion and absorption. These peptides promise to play a role in preventing and treating metabolic diseases due to their dual inhibitory effects on ACE and DPP-IV.

• Steel and Composite Structures
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• v.50 no.6
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• pp.705-720
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• 2024

Analyzing the collapse behavior of thin-walled steel structures holds significant importance in ensuring their safety and longevity. Geometric imperfections present on the surface of metal materials can diminish both the durability and mechanical integrity of steel shells. These imperfections, encompassing local geometric irregularities and deformations such as holes, cavities, notches, and cracks localized in specific regions of the shell surface, play a pivotal role in the assessment. They can induce stress concentration within the structure, thereby influencing its susceptibility to buckling. The intricate relationship between the buckling behavior of these structures and such imperfections is multifaceted, contingent upon a variety of factors. The buckling analysis of thin-walled steel shell structures, similar to other steel structures, commonly involves the determination of crucial material properties, including elastic modulus, shear modulus, tensile strength, and fracture toughness. An established method involves the emulation of distributed geometric imperfections, utilizing real test specimen data as a basis. This approach allows for the accurate representation and assessment of the diversity and distribution of imperfections encountered in real-world scenarios. Utilizing defect data obtained from actual test samples enhances the model's realism and applicability. The sizes and configurations of these defects are employed as inputs in the modeling process, aiding in the prediction of structural behavior. It's worth noting that there is a dearth of experimental studies addressing the influence of geometric defects on the buckling behavior of cylindrical steel shells. In this particular study, samples featuring geometric imperfections were subjected to experimental buckling tests. These same samples were also modeled using Finite Element Analysis (FEM), with results corroborating the experimental findings. Furthermore, the initial geometrical imperfections were measured using digital image correlation (DIC) techniques. In this way, the response of the test specimens can be estimated accurately by applying the initial imperfections to FE models. After validation of the test results with FEA, a numerical parametric study was conducted to develop more generalized design recommendations for the stainless-steel shell structures with the initial geometric imperfection. While the load-carrying capacity of samples with perfect surfaces was up to 140 kN, the load-carrying capacity of samples with 4 mm defects was around 130 kN. Likewise, while the load carrying capacity of samples with 10 mm defects was around 125 kN, the load carrying capacity of samples with 14 mm defects was measured around 120 kN.

• Journal of Environmental Health Sciences
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• v.50 no.2
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• pp.146-156
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• 2024

Background: Children who use playground facilities are exposed to potential risks due to the high concentration of heavy metals contained in the finishing materials of facilities in children's playgrounds. Objectives: The purpose of this study was to investigate the concentration of heavy metals in the finishing materials of outdoor children's playgrounds where harmful heavy metals exist in Gwangju and to conduct human risk assessment for children and adults by age to find the risks and limitations. Methods: The bottom and top layers of double-painted paint were peeled off and collected together from the finishing materials of children's play facilities such as slides, swings, and seesaws in 147 children's parks in Gwangju. Heavy metals were analyzed using ICP-OES, etc., and human risk assessment was performed using the concentrations of heavy metals. Results: Based on 1.0E-04, which requires legal regulation, CTE was found to pose a carcinogenic risk for preschool children and no carcinogenic risk for the rest of the age groups. However, RME showed that both men and women of all ages had a carcinogenic risk. For reference, when the carcinogenic risk was based on 1.0E-06, CTE was found to pose a carcinogenic risk from infants to elementary school students, and RME was found to have a carcinogenic risk in all age groups. It was judged that there is a non-carcinogenic risk if the non-carcinogenic risk exceeds 1 based on the hazard index (HI) 1. In CTE, there was no non-carcinogenic risk, and RME for preschooler males (1.49E+00) and females (1.56E+00) were found to have non-carcinogenic risk. Conclusions: This study was meaningful in that it examines the differences in the current management of heavy metals concentration standards and potential carcinogenic and non-carcinogenic risks to the human body and discusses the relationship between heavy metals and human health effects.

• Journal of Trauma and Injury
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• v.18 no.2
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• pp.81-86
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• 2005

Background: Cardiac troponin I (cTnI) is a sensitive cardiac marker of myocardial injury. In normal coronary angiogram, positive cTnI values may be detected in various events such as sepsis, stroke, trauma and so on. To investigate characteristics of cTnI positive group in trauma patients, we designed this study between cTnI positive group and cTnI negative group. Method: Trauma patients who visited emergency room within 24 hours after accidents were included. Patients who had renal failure, acute coronary syndrome, sepsis, spontaneous SAH were excluded. Retrospective study of 97 trauma patients was done. We investgated ISS (injury severity score), positive cTnI, EKG abnormality, shock class, ICU admission rate and mortality. Result: In comparing with non chest trauma group, chest trauma group, whose chest AIS (Abbreviated Injury Score) is more than 3 point, had significant values in ISS, positive cTnI, EKG abnormality, shock class and ICU admission rate. Also, in non chest trauma group, we found several patients whose cTnI level was positive. When non chest trauma group was divided into two subgroups, the mortality and shock class of positive cTnI group were higher than that of negative cTnI group. When all trauma patients were divided into two groups, a positive cTnI group had higher values in ISS, shock class, ICU admission rate and mortality than that in a negative cTnI group. Conclusion: We found that cTnI were positive in patients of cardiac contusion but also in various trauma cases. In non chest trauma patients, we assumed that hypotension caused cTnI elevating. The cTnI could play a role in predicting prognosis in trauma patients.

• Korean Journal of Head & Neck Oncology
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• v.27 no.2
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• pp.198-203
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• 2011

Background and Objectives : Distinguishing benign from malignant lesion in thyroid noddex is important but clinically difficult. FNAB is the first investigation of choice. However, cytologic results are often indeterminable. In those cases, additional molecular biologic tests are helpful. If serologic tests are available to predict malignancy, it can be useful to fortify accurate diagnosis. We analyzed whether TSH or FreeT4 level could be used as a predictor of malignancy. Materials and Methods : From January 2008 to March 2009, 540 patients received one of thyroidectomy in a single center. We only included 167 patients from 18 to 65 years old without cardiopulmonary or renal disorders. All the patients were in euthyroid state and took no medications, which affect the thyroid function. We reviewed charts retrospectively to find out differences in TSH level and FreeT4 level between the benign and malignant groups. Results : In this study, all the patients with malignancy had the papillary cancer. In benign group, average TSH level came out to be 1.48mU/L, whereas the average TSH level of malignant group was 1.98 mU/L. Moreover, the higher the cancer stage was, the higher the TSH level was. Although we have adjusted factors that can affect TSH level(age, sex, race, goiter type), we still received the same result. The risk of malignant cancer increased in proportion with TSH level within the normal range. In free T4 level, there was no difference between benign and malignant group. Conclusion : We propose that TSH level can play a role as one of the predictors for thyroid cancer. However, there is limitation because all the patients with malignancy in this study have papillary cancer. Thus, we can apply this result only in papillary cancer, and we need more study for other types of thyroid cancer.