• Korean Journal of Soil Science and Fertilizer
• /
• v.38 no.3
• /
• pp.142-149
• /
• 2005

This investigation was conducted to observe and verify the distribution and their occurrence between heavy metals and natural isotopes in the soil collected at the 40 locations from the abandoned coal mine areas to the sediment of Chungra reservoir located at Chungra-Myon Boryung city, Chungnam. The results of the investigation showed that there were distinctive differences of the contents for the heavy metals and the natural isotopes between the area influenced by the coal mine tailing and the non-influenced area. The amounts of the heavy metals were Pb ($1.32-29.96mg\;kg^{-1}$), Cd ($0.15-0.76mg\;kg^{-1}$), Cu ($0.28-49.67mg\;kg^{-1}$), and Cr ($1.31-13.18mg\;kg^{-1}$) while the averages were Cu ($12.43mg\;kg^{-1}$), Pb ($10.44mg\;kg^{-1}$), Cr ($4.87mg\;kg^{-1}$), Cd ($0.51mg\;kg^{-1}$). The standard deviations of Pb and Cu were significantly higher compared to other heavy metals investigated in this experiment. And the amounts of the natural isotopes measured from the dried soil samples were Pb-210 ($4.87dpm\;g^{-1}$), Th-234 ($3.52dpm\;g^{-1}$), Ra-226 ($2.88dpm\;g^{-1}$), Ra-228 ($7.30dpm\;g^{-1}$), K-40 ($58.06dpm\;g^{-1}$) for all locations whereas Cs-137 which is fall-out by nuclear experiment from atmosphere was rarely found. From these results we found that the amounts of natural isotopes such as Pb-210 (4.41%), Th-234 (3.60%), and Ra-226 (2.09%) were less than those found in the coal-tailing while the proportion of Ra-228 (266%) and K-40 (308%) were significantly higher than those in the coal-tailing. Also occurrence of correlations between the amounts of the heavy metals and the natural isotopes was proportionally related.

• Journal of Food Hygiene and Safety
• /
• v.26 no.1
• /
• pp.49-56
• /
• 2011

To investigate the toxicological effects of ${\beta}$-glucan, we performed basic studying on ${\beta}$-glucan in Sprague-Dawley (SD) rats. Standard endpoints in this study included mortality, clinical observations, changes of body weights, analysis on food consumption, ophthalmoscopic examination, hematologic examination, serum biochemistry, analysis of organ weights, gross anatomic pathology and histopathology. No clinical signs and mortality were observed in animals treated with beta-glucan throughout the experimental period. The average body weight of each treatment groups showed similar levels at end of experiment. There were no treatment-related changes in mortality, body weights changes, food consumption, ophthalmoscopic examination. Although there were statistically significant differences between the control and treated groups in some relative and absolute organ weights, and hematological and biochemical analysis, the data were in biologically normal ranges and did not show a dose-dependent manner. In the morphological change, hepatic tissue were not showed ballooning degeneration and irregular arrangement of hepatic cell in ${\beta}$-glucan treatment groups with control group. Also, organs weights (liver, heart, kidney and stomach) and hematological indices (WBC, RBC, Hb, Hct and Platelet) did not show statistically significant differences among the experimental groups. In summary of these results, there were no changes in mortality, mean body weight, clinical signs, food consumption. There were no changes in ophthalmological examination, hematology, blood chemistry, necropsy and histopathology. In conclusion, although further investigation of glucan should be performed in the functions registered in many ancient literatures, ${\beta}$-glucan is physiologically safe and may have potential as candidate food for human health.

• Journal of Preventive Medicine and Public Health
• /
• v.29 no.3 s.54
• /
• pp.539-553
• /
• 1996

The study was conducted from May to September in 1994 to investigate applicability of the Hearing Handicap Inventory for the Elderly-Screening version(HHIE-S) in parallel with the pure-tone audiometer to the initial screening test of noise-induced hearing loss(NIHL) in some noise-exposed workers. Subjects were selected by systemic sampling that took every 10th person from 6, 700 workers taking the annual occupational health examination by the department of Health Maintenance of Dongsan Hospital Keimyung University in Taegu. The authors administered the pure-tone audiometric test and self-reported questionnaire of HHIE-S including items of sociodemographic and job-related variables concurrently. The final subjects analysed were 1,019(488 males and 531 females) excluding fourteen persons who had many missing values in their questionnaires. The reliability coefficients of HHIE-S scale by Cronbach's alpha were 0.84. In the univariate analysis of hearing handicap measured by the HHIE-S, work duration, military service and the hearing threshold loss at 1KHz and 4KHz by the initial audiometer were significant in males while age, work duration and hearing threshold loss at 1KHz and 4KHz were significant in females. In the stepwise linear regression analysis, hearing threshold loss at 1KHz and 4KHz, was the only selected variable explaining the hearing handicap in males and hearing threshold loss at 1KHz and 4KHz, age, and work duration were selected in females. In ROC curves for HHIE-S scores against NIHL as gold standard which was defined by the follow-up audiogram as more than 30dB of the average of 0.5/1/2KHz and 50dB at 4KHz, the optimal cutoff for the parallel HHIE-S appeared to be 8. The results suggest that HHIE-S appeared to have some reliability and validity in this data and might be used in screening NIHL in parallel with pure-tone audiometer in noise-exposed workers.

• Journal of Science Education
• /
• v.44 no.1
• /
• pp.92-111
• /
• 2020

The 2015 revised science curriculum and NGSS (Next Generation Science Standard) suggest computational thinking as an inquiry skill or competency. Particularly, concern in computational thinking has increased since the Ministry of Education has required software education since 2014. However, there is still insufficient discussion on how to integrate computational thinking in science education. Therefore, this study aims to prepare a way to integrate computational thinking elements into scientific inquiry by analyzing the related literature. In order to achieve this goal, we summarized various definitions of the elements of computational thinking and analyzed general problem solving process and scientific inquiry process to develop and suggest the model. We also considered integrated problem solving cases from the computer science field and summarized the elements of the Computational Thinking-Scientific Inquiry (CT-SI) model. We asked scientists to explain their research process based on the elements. Based on these explanations from the scientists, we developed 'Problem-finding' CT-SI model and 'Problem solving' CT-SI model. These two models were reviewed by scientists. 'Problem-finding' model is relevant for selecting information and analyzing problems in the theoretical research. 'Problem solving' is suitable for engineering problem solving process using a general research process and engineering design. In addition, two teachers evaluated whether these models could be used in the secondary school curriculum. The models we developed in this study linked with the scientific inquiry and this will help enhance the practices of 'collecting, analyzing and interpreting data,' 'use of mathematical thinking and computer' suggested in the 2015 revised curriculum.

• Journal of Chest Surgery
• /
• v.42 no.2
• /
• pp.226-232
• /
• 2009

Background: Blunt chest trauma accounts for 90% of all chest traumas in Europe and the United States and this causes 20% of all trauma-related deaths. The major cause of morbidity and mortality after blunt chest trauma is undetected injuries. For this reason, chest computerized tomography has gained popularity for the evaluation of trauma, but it is expensive and it exposes patients to radiation. This study identified the clinical features associated with the diagnosic information obtained on a CT chest scan, as compared with a standard chest X-ray, for patients who sustained blunt trauma to the chest. This study also evaluated the role of a routine computed tomographic (CT) scan for these patients. The patients who had chest computed tomography done after the initial chest x-ray were analyzed separately for the presence of occult injuries. Material and Method: We studied 100 consecutive patients from November 2006 to July 2007: 74 patients after motor vehicle crashes and 26 patients after a fall from a height >2m. Simultaneous with the initial clinical evaluation, an anteroposterior chest radiograph and a helical chest CT scan were obtained for all the patients. The data extracted from the medical record included the vital signs, the interventions and the type and severity of injury (RTS). Result: Among the 100 cases, 79 patients showed at least more than one pathologic sign on their chest radiograph, and 21 patients had a normal chest radiograph. For 17 of the patients who had a normal chest X ray, the CT scan showed multiple injuries, which were pneumothorax, hemothorax, lung contusion, sternal fracture etc. This represents that a CT scan is statistically superior to a chest radiograph to diagnose the pathologic signs. But on the other hand, as for treatment, only 31 patients were diagnosed by CT scan and they were treated with chest tube insertion ect. 42 patients needed ony conservative management without invasive thoracosurgical treatment such as chest tube insertion or open thoracotomy. 27 patients were treated based on the diagnosis made by the chest radiograph and physical examination. Conclusion: Chest computerized tomography was significantly more effective than routine chest X-ray for detecting lung contusion, pneumothorax and mediastinal hematoma, as well as fractured ribs, scapula and, sternum. Although the occult findings increased, the number of patients who needed treatment was small. Therefore, we suggest making selective use of a CT scan to avoid its overuse in ERs.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.10
• /
• pp.578-589
• /
• 2018

Building Integrated Photovoltaic (BIPV) system is a typical integrated system that simultaneously performs both building function and solar power generation function. To maximize its potential advantage, however, the solar photovoltaic power generation function must be integrated from the early conceptual design stage, and maximum power generation must be designed. To cope with such requirements, preliminary research on BIPV design process based on architectural design model and computer simulation results for improving solar power generation performance have been published. However, the requirements of the BIPV system have not been clearly identified and systematically reflected in the subsequent design. Moreover, no model has verified the power generation design. To solve these problems, we systematically model the requirements of BIPV system and study power generation design based on the system requirements model. Through the study, we consistently use the standard system modeling language, SysML. Specifically, stakeholder requirements were first identified from stakeholders and related BIPV standards. Then, based on the domain model, the design requirements of the BIPV system were derived at the system level, and the functional and physical architectures of the target system were created based on the system requirements. Finally, the power generation performance of the BIPV system was evaluated through a simulated SysML model (Parametric diagram). If the SysML system model developed herein can be reinforced by reflecting the conditions resulting from building design, it will open an opportunity to study and optimize the power generation in the BIPV system in an integrated fashion.

• Clinical and Experimental Pediatrics
• /
• v.48 no.9
• /
• pp.953-959
• /
• 2005

Purpose : The administration of total parenteral nutrition(TPN) has become a standard procedure in the management of nutritionally deprived and critically low birth weight neonates. Sepsis remains the most frequent serious complication during TPN, resulting in increased morbidity, mortality and health care costs. This study was performed to evaluate the clinical efficacy and complications of percutaneous central venous catheterization(PCVC) in very low birth weight infants. Methods : A total of 56 very low birth weight infants below 1,500 g during the period from January 1998 to December 2003 were enrolled and their medical records reviewed. Study group(n=32) included the babies who had undergone PCVC and a control group(n=24) included babies who had not undergone PCVC. We compared the study group with the control group for factors such as subject characteristics and catheter-related complications. Results : There was no difference in subject characteristics, such as birth weight, gestational week, respiratory distress syndrome, duration of ventilator therapy, duration from tube to complete oral feeding, days at TPN and its total duration, body weight at discontinuation of TPN and the days taken to reach to 2,000 g. However, the morbidity rate due to patent ductus arterious, chronic lung disease, necrotizing enterocolitis, osteopenia, cholestasis, and sepsis showed no difference. The study group with infants below 1,000 g showed a higher incidence of sepsis compared to the control group of the same weight group. The study group with infants between 1,000 to 1,500 g showed significantly higher incidences of intraventricular hemorrhage and took longer reach the a body weight of 2,000 g. Conclusion : Considering the high incidence of sepsis in the PCVC group, every attempt should be made to minimize the length of TPN therapy and encourage early enteral feeding. We also recommend the use of PCVC carefully in patients requiring prolonged nutritional support.

• Cartoon and Animation Studies
• /
• s.30
• /
• pp.113-137
• /
• 2013

The accessibility and effect of cartoon on children are very significant. Since cartoon is a medium of conveying information through text and pictures, it has a characteristic of being easily approached by children than any other medium. Its accessibility to children is inevitably more exceptional than any other medium in the sense that it is a method of not only telling or reading stories but also showing stories. The main audience of is children. It has a characteristic of being easily accepted by children since it's mythology seen in cartoon than read in text. However, gods conducts are full of unethical expressions. Sexual expressions of intermarriages between mother and son, between brother and sister and between uncle and niece, as well as extramarital intercourse are very unethical that could have negative effects on children. This study analyzed the unethical expressions of gods that could have negative effects on children at current point in time. Zeus was often unfaithful to his wife with many stories about the children of Zeus that were created from extramarital intercourse. Standard of value on rational decision has been established for adult readers, but children can readily accept things since they lack their own rational decision on what's right and wrong. As an alternative to children's uncritical observatory study, there is a need for author's intervention to help children form desirable values. The purpose of this study is to analyze the sexual expressions of Zeus and gods in that could affect children's social study.

• Journal of the Korean Wood Science and Technology
• /
• v.46 no.1
• /
• pp.48-59
• /
• 2018

This study was conducted to suggest the effective management and recycling processes of coffee waste, which can be easily obtained from coffee shops and coffee-related products industries. Prior to the fabrication of pellets, the potential of coffee waste as a raw material of pellet was investigated through the examination of its chemical compositions and fuel characteristics. Major gradient included in coffee waste was holocellulose, followed by fat/oil and protein. Coffee waste contained a small quantity of ash (0.7%), such as calcium, sodium, potassium and magnesium. Interestingly, coffee waste was easily dried probably due to its porous structure. Pellets fabricated with coffee waste and larch sawdust showed good fuel characteristics, such as moisture content, ash content, density and durability. The pellets exceed greatly the minimum requirements of $1^{st}$-grade wood pellet standard designated by National Institute of Forest Science (NIFOS). Particularly, the high calorific value of coffee waste showed the potential as a raw material of pellet. However, owing to high nitrogen and sulfur contents, coffee waste is like to be used as a raw material of wood pellet for combined heat and power plants equipped with a reduction system of $NO_x$ and $SO_x$ gases. On the other hand, 91 wt% larch sawdust and 9 wt% coffee waste are required to fabricate the $1^{st}$-grade wood pellets designated by NIFOS. Pellets fabricated with the conditions are estimated to have nitrogen content of 0.298% and sulfur content of 0.03%. Lastly, if amounts of coffee waste and sawdust in the production of wood pellets are adequately adjusted according to its purchasing price, the manufacturing cost of pellet can effectively be reduced. In addition, it is expected tp prepare the effective recycling process of waste and to relieve the environmental burden with the reduction of waste from the commercialization of coffee waste/larch pellets.

• The Journal of the Petrological Society of Korea
• /
• v.18 no.4
• /
• pp.315-336
• /
• 2009

We have studied the orientational characteristics of microcrack frequency, it's length and density in Tertiary crystalline tuff from the northeastern part of the Gyeongsang Basin. 134 sets of microcracks on horizontal surfaces of 3 rock samples from Heunghae-eup were distinguished by enlarged photomicrographs of the thin sections. The variability in patterns among microcrack length-frequency histograms for three rock samples from different altitudes were derived. The pattern of histograms changes progressively from negative exponential form to log-normal form in proportion to altitude. The distribution pattern for rock sample no.1 from lower altitude shows the broad length distribution characterized by higher mean and median, and higher standard deviation. Meanwhile, this distribution pattern corresponds with characteristics of joint length distribution in sedimentary rocks of the lower part of the Gyeongsang Supergroup. The occurrence frequency of shorter microcracks increases toward both NW and NE directions from the $N0{\sim}10^{\circ}W$, with the dominant direction of $N80{\sim}90^{\circ}W$ and $N80{\sim}90^{\circ}E$, respectively. This distribution pattern represents the relative differences in formation timing among microcrack sets and the result of the new initiation of shorter microcracks. Meanwhile, the longest microcracks within $N60{\sim}70^{\circ}W$($L_{max}$:1.18 mm) and $N0{\sim}10^{\circ}W$($L_{max}$:0.80 mm) directions are seen, but this kind of microcracks are very limited in number. Whole domain of the directional angle($\theta$)-frequency(N), length(L) and density($\rho$) chart can be divided into five sections in terms of phases of the distribution of related curves. From the distribution chart, density curve shows five distinct peaks in the WNW-ESE($N70{\sim}80^{\circ}W$), NS~NNE-SSW($N0{\sim}10^{\circ}W$, $N10{\sim}20^{\circ}E$), ENE-WSW($N50{\sim}60^{\circ}E$), and nearly EW($N80{\sim}90^{\circ}E$) directions, respectively. Especially, main directions of faults correspond with the directional angle showing high density. Consequently, these distribution patterns of density curve reflect the representative maximum principal stress orientations suggested in previous studies.