• Journal of The Korean Association For Science Education
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• v.31 no.4
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• pp.513-527
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• 2011

There have been studies about conceptual ecology making a profound study of conceptual changes in learners' cognitive structure. Because learners' cognitive structure have been compared to ecology, it is natural to think that conception in learner's cognitive structure have a niche as species in ecology have niches. Therefore, it is necessary to study niche approach about conception that learners recognize in their cognitive structure. The purposes of this study were to identify relationships among conceptions that 5th grade elementary school students recognize about photosynthesis and to identify how these relationships among conceptions about photosynthesis change before and after a class of photosynthesis in curriculum in terms of an approach of ecological niche which are composed of 3 domains - diversity of conceptions, relevance and frequency rate of conceptions, and competition among conceptions. Open ended questionnaire was developed by 4 fields: photosynthetic place, photosynthetic products, photosynthetic materials needed and environment factors of photosynthesis. The subjects sampled in this study were 310 5th grade elementary students in 5 cites. Before and after classes in photosynthesis in science curriculum, students were asked to write down conceptions that they knew about the 4 fields of photosynthesis of questionnaire and to write down scales of relevance from 1 to 30 about how they think the conceptions are related to the field of photosynthesis. The results of this study showed the following: First, most students have had a variety of conceptions and commonly recognized 'light' and 'water' as concepts in photosynthesis. Second, students still recognized their preconceptions like 'soil' and 'root,' etc. that were far from scientific conceptions of photosynthesis although they took classes in photosynthesis. Third, students needed to take the various strategies of teachers because they did not recognized scientific conceptions appropriately about photosynthetic fields. Fourth, it appeared that photosynthetic conceptions recognized by students had status in terms of relevance and frequency rate of conceptions, and competition among conceptions, and that they looked like the niche of conceptions in their conceptual ecologies.

• 대한공업교육학회지
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• v.42 no.1
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• pp.30-52
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• 2017

The purpose of this study is to investigate the duties of teachers working at secondary level technical vocational education institutes, and analyze job importance, difficulty and frequency of performance perceived by teachers. For deducing the duties of teachers working at secondary level technical vocational education institutes, they were theoretically devised by reviewing related legislations & regulations and domestic & overseas literatures. The devised duties were reviewed by 16 current teachers and 3 education experts to be revised and supplemented to complete the job model. Based on this, development of research tool was finalized, and questionnaires were used as the research tool. The results of this study are as follow. First, the job categories of teachers working at secondary level technical vocational education institutes consisted of 7 categories that are subject instruction, student instruction, class management, curriculum organization & administration, school affairs & administrative duties, PR & field practical training and expertise enhancement. Based on the CFA, they consisted of 46 sub-factors in 10 categories with 3 categories of lesson preparation & planning, lesson administration and academic evaluation for subject instruction, and 2 categories of extracurricular student guidance and school life guidance for student instruction, and class management, curriculum organization & administration, school affairs & administrative duties, PR & field practical training and expertise enhancement. Second, job importance perceived by teachers working at secondary level technical vocational education institutes was found to be high overall with 4.10, while above average in difficulty with 3.45 and average in frequency of performance with 3.12 (1-3 times a month). As for categories with high job importance, they were found to be in the order of academic evaluation (4.32), lesson preparation & planning (4.28), expertise enhancement (4.27), lesson administration (4.26), school life guidance (4.25), class management (4.17) and PR & field practical training (4.12). In regards to categories with high job difficulty, they were found to be in the order of PR & field practical training (4.07), curriculum organization & administration (3.73), expertise enhancement (3.55), school life guidance (3.48), academic evaluation (3.35) and extracurricular student guidance (3.22). As for categories with high frequency of job performance, they were found to be in the order of class management (3.88), lesson administration (3.77), school life guidance (3.52), school affairs & administrative duties (3.40) and lesson preparation & planning (3.17).

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.11
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• pp.1615-1634
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• 2004

A review was undertaken to obtain information on the sustainability of pig free-range production systems including the management, performance and health of pigs in the system. Modern outdoor rearing systems requires simple portable and flexible housing with low cost fencing. Local pig breeds and outdoor-adapted breeds for certain environment are generally more suitable for free-range systems. Free-range farms should be located in a low rainfall area and paddocks should be relatively flat, with light topsoil overlying free-draining subsoil with the absence of sharp stones that can cause foot damage. Huts or shelters are crucial for protecting pigs from direct sun burn and heat stress, especially when shade from trees and other facilities is not available. Pigs commonly graze on strip pastures and are rotated between paddocks. The zones of thermal comfort for the sow and piglet differ markedly; between 12-22$^{\circ}C$ for the sow and 30-37$^{\circ}C$ for piglets. Offering wallows for free-range pigs meets their behavioural requirements, and also overcomes the effects of high ambient temperatures on feed intake. Pigs can increase their evaporative heat loss via an increase in the proportion of wet skin by using a wallow, or through water drips and spray. Mud from wallows can also coat the skin of pigs, preventing sunburn. Under grazing conditions, it is difficult to control the fibre intake of pigs although a high energy, low fibre diet can be used. In some countries outdoor sows are fitted with nose rings to prevent them from uprooting the grass. This reduces nutrient leaching of the land due to less rooting. In general, free-range pigs have a higher mortality compared to intensively housed pigs. Many factors can contribute to the death of the piglet including crushing, disease, heat stress and poor nutrition. With successful management, free-range pigs can have similar production to door pigs, although the growth rate of the litters is affected by season. Piglets grow quicker indoors during the cold season compared to outdoor systems. Pigs reared outdoors show calmer behaviour. Aggressive interactions during feeding are lower compared to indoor pigs while outdoor sows are more active than indoor sows. Outdoor pigs have a higher parasite burden, which increases the nutrient requirement for maintenance and reduces their feed utilization efficiency. Parasite infections in free-range pigs also risks the image of free-range pork as a clean and safe product. Diseases can be controlled to a certain degree by grazing management. Frequent rotation is required although most farmers are keeping their pigs for a longer period before rotating. The concept of using pasture species to minimise nematode infections in grazing pigs looks promising. Plants that can be grown locally and used as part of the normal feeding regime are most likely to be acceptable to farmers, particularly organic farmers. However, one of the key concerns from the public for free-range pig production system is the impact on the environment. In the past, the pigs were held in the same paddock at a high stocking rate, which resulted in damage to the vegetation, nutrient loading in the soil, nitrate leaching and gas emission. To avoid this, outdoor pigs should be integrated in the cropping pasture system, the stock should be mobile and stocking rate related to the amount of feed given to the animals.

• Journal of Bio-Environment Control
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• v.22 no.2
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• pp.182-187
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• 2013

In closed plant production system like plant factory, changes in environmental factors should be identified for conducting efficient environmental control as well as predicting energy consumption. Since high relative humidity (RH) is essential for crop production in the plant factory, transpiration is closely related with RH and should be quantified. In this study, four varieties of lettuces (Lactuca sativa L.) were grown in a plant factory, and the leaf areas and transpiration rates of the plants according to DAT (day after transplanting) were measured. The coefficients of the simplified Penman-Monteith equation were calibrated in order to calculate the transpiration rate in the plant factory and the total amount of transpiration during cultivation period was predicted by simulation. The following model was used: $E_d=a*(1-e^{-k*LAI})*RAD_{in}+b*LAI*VPD_d$ (at daytime) and $E_n=b*LAI*VPD_n$ (at nighttime) for estimating transpiration of the lettuce in the plant factory. Leaf area and transpiration rate increased with DAT as exponential growth. Proportional relationship was obtained between leaf area and transpiration rate. Total amounts of transpiration of lettuces grown in plant factory could be obtained by the models with high $r^2$ values. The results indicated the simplified Penman-Monteith equation could be used to predict water requirements as well as heating and cooling loads required in plant factory system.

• 한국벤처창업학회:학술대회논문집
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• 2007.04a
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• pp.375-404
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• 2007

When we look into the market economy of our country recently, we learn that the mind of consumption after IMF crisis is very shrunk and the market is led into a serious slump of consumption. For an approach to survive the contraction of the market and the market competition, enterprises command a variety of sales promotion strategy, out of which presentation is a sales promotion strategy to give the same product. The price-discounted strategy through the provision of donation commodity may induce the temporarily-discounted commodity not to be sold to the consumers or make a damage of the images of the brand, or arouse the price war against other companies, or lower the sense of the quality of the commodity. Therefore, it is necessary for a company to meet the end users' demand and also maintain the evaluation of the quality on the consumers' products highly. Therefore, in this study, we have attempted to study and analyze the consumers' satisfaction level and reliability on the donation goods in order to suggest the orientation of the presentation promotion strategy in accordance with the changes of the sales market. In addition, we tried to understand how the recognition, consumers' satisfaction level and reliability on the presentation goods had on the repurchase. With such objectives in this study, we could make an analogy of the following significance and suggestion of study. Firstly, in order to survive a serious competition market, enterprises must execute the product presentation along with diverse events instead of commanding the sales promotion strategy through a simple product presentation. This strategy can be an alternative to lower the danger a person-to-person product presentation may bring about. That is to say, we shall not lower the quality and value of the products but enhance a new image to customers through a product donation occasion together with an event as a new marketing pioneering method. Secondly, during the period of the current economic depression, if a company provides the consumers with an opportunity free of charge through the present special event period and the practical events, it will affect the advertising effect of the goods, the introduction of the customers and customers' repurchase. For this purpose, the company has to heighten customers' preferences by selecting the items customers are liable to prefer and closely analyze the consumer's response and market for such an objective. Thirdly, with the internet age, as the market has a tendency to increase in the number of consumers who do shopping in the internet, the marketing strategy has to build up the strategy of the presentation product instead of a simple offline strategy. For example, a company shall have to draw attention or attraction from end users who intend to do shopping through the online by a product planning expo or a presentation product corner. Fourthly, the excessive sale promotion strategy of presentation products may bring about even a reverse effect on the value of the goods or consumers' attitude as seen above. Therefore, a company has to relay 'the value as to the price' to the consumers instead of the sales promotion strategy of donation products just for a temporary sales volume. Conclusively, even if we put the value with a reasonable price through the presentation product strategy in the past, we shall have construct the strategy by providing some plus factors in the price such as the provision of the upgraded products or services instead of just presentation, or the invitation of the events related to diverse events or culture arts from now on.

• Journal of Mushroom
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• v.2 no.3
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• pp.115-126
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• 2004

Somatic hybrids of inter-compatible and inter-incompatible strains were obtained by protoplast fusion. The fusion products between compatible strains, Pleurotus ostreatus and P. florida, formed heterokaryons, while fusants between incompatible strains such as P. cornucopiae + P. florida, P. ostreatus + Ganoderma applanatum, P. florida + Ganoderma lucidum, and P. ostreatus + Flammulina velutipes formed synkaryons that retained genes from both parents. The heterokaryons showed the same level of basidioma development. In contrast, the synkaryons showed unique characteristics including clamp connection formation at mitosis, either partner basidioma development, and abnormal segregation and recombination compared with inter-compatible strains. Synkaryons can be classified into homokaryoyic and heterokaryotic type. A comparison of somatic hybrids with compatible and incompatible strains was made using random amplified polymorphic DNA (RAPD) analysis. The heterokaryons between compatible species showed the same level of variability and contained both parental RAPD bands. In contrast, most of the synkaryons between incompatible species showed similarity to those of either parental bands and non-parental RAPD bands. Synkaryons can be classified into microgenome insertion type and macrogenome insertion type. A tetrapolar mating system was found among monospore isolates in somatic hybrids and wild type P. ostreatus. Homokaryons from each somatic hybrid combination were paired with tester homokaryons of the initial wild type of P. ostreatus. The changed mating types were identified in progenies. The pattern of mating type switching in somatic hybrids depends on compatibility of fusion partner. There are several factors related to the mechanism of clamp connection formation and fruiting body development of synkaryons. Of these,the major factor may be associated with self-fertility and mating type switching such as homokaryotic fruiting of wild type P. ostreatus. This review will discuss these aspects.

• Clinical and Experimental Pediatrics
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• v.48 no.12
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• pp.1342-1347
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• 2005

Purpose : Among perinatal risk factors, neonatal seizures are one of the strongest independent discriminators of adverse outcome, representing high risks of mortality and neurologic morbidity. This study was undertaken to evaluate the neurologic outcome of neonatal status epilepticus according to underlying etiology, seizure pattern, onset time, and duration. Methods : We reviewed retrospectively 36 neonates(19 males, 17 females) with status epilepticus who were admitted to the neonatal intensive care unit, Inha Hospital between July, 1988 and June, 2003. They were evaluated with neurologic examination, laboratory data, EEG findings, and neuroimaging studies etc. Results : The mean gestational period of the patients was $37.0{\pm}3.6$ weeks and birth weight was $2.70{\pm}0.82$ kilogram. Fifty two point eight percent of the neonates were male and 66.7 percent were born at term. The most common cause of neonatal status epilepticus was hypoxic-ischemic encephalopathy. In preterm babies, intracranial hemorrhages showed an especially high frequency(P=0.034). Gestational age and birth weight did not show a correlation with neurologic complications. The incidence of neurological sequelae were significantly related to prolonged seizures lasting more than 1 hour(P=0.002). Neonates with seizures within the first 72 hours tended to be more frequent among those who developed adverse outcomes(P=0.016). Generalized tonic seizures had the worst prognosis, whereas those children who had subtle seizures had better outcomes than any other type(P<0.05). Generalized tonic seizures were primarily represented on EEG by abnormal background, whereas subtle seizure showed a significantly more normal EEG than any other seizures(P<0.05). Conclusion : Our results indicate that neonatal status epilepticus with early onsets, prolonged durations. And generalized tonic types can predict an increased risk for neurologic sequelae. So, those seizures must be perceived as medical emergencies and treated aggressively with antiepileptic drugs.

• Clinical and Experimental Pediatrics
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• v.52 no.5
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• pp.544-548
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• 2009

Purpose : To elucidate a potential association between Helicobacter pylori (HP) infection and iron-deficiency anemia (IDA) in infants and children in terms of the other factors related to iron utilization and storage although the association of ferritin was previously studied. Methods : We evaluated 135 infants (aged 6-24 months) admitted at Gyeongsang National University Hospital from 2000 to 2006. Western blot assays using the HP CagA antigen (120 kD) were conducted to identify infections. The concentrations of six parameters were measured: hemoglobin (Hb), serum ferritin, soluble serum transferrin receptors, interleukin-6, prohepcidin, and C-reactive protein. In addition, the infants were classified into IDA, anemia from inflammation (AI), unclassified anemia (UCA), and normal groups on the basis of Hb and ferritin concentrations. Results : In the IDA group (n=20), seven infants were infected with HP, with the other infants showing no evidence of infection. The mean Hb levels in the IDA group were significantly lower in HP-infected infants than those uninfected (7.1 vs. 8.2 g/dL, respectively); the mean ferritin levels were also significantly lower in the infected infants (3.2 vs. $6.8{\mu}g/L$). The other four parameters did not differ significantly among the IDA infants. No correlations were found between the six parameters and HP infection status in the other groups. Conclusion : There were no significant differences in the HP infection rates among the study groups. However, in the IDA group, the HP-infected infants had significantly lower serum ferritin and Hb levels than the HP-negative infants (P<0.05).

• Journal of Nutrition and Health
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• v.42 no.7
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• pp.615-621
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• 2009

This study was conducted to evaluate the change of nutritional status and to analyze related factors in hospitalized tuberculosis (TB) patients during their hospitalization. The subjects were 398 men patients (mean age: 47.3 ${\pm}$ 14.4 y) who had hospitalized more than 3 months at TB hospital located in Seoul. The anthropometric and blood biochemical indices were measured, and dietary intakes were assessed. At the time of admission the body weight of subjects was about 76% of the average body weight of Korean men with same age, Body mass index (BMI) of subjects was 18.5 kg/$m^2$, and 53.8% of subjects were under weight status. Average level of blood hemoglobin and hematocrit of subjects was lower than the normal value. After 3 months of hospitalization period, the body weight and body mass index were significantly increased compared to admission by 3.9 kg (7.41%) and 1.4 kg/$m^2$ (7.61%)(p < 0.001), respectively. Blood levels of hemoglobin, hematocrit, albumin, and total protein were also significantly increased after 3 months of hospitalization period compared to admission (p < 0.001). The increment in the body weight and blood indices was significantly higher in below 29 years group than over 60 years group (p < 0.05). The increment in the body weight and body mass index was significantly higher in the under-body weight group compared to the normal-body weight group (p < 0.05). In conclusion the body weight and body mass index of subjects were significantly increased after 3 months of hospitalization period, and the age and body weight of subjects at admission were supposed to influence the degree of change in the nutritional status.

• Journal of Korean Society of Forest Science
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• v.97 no.6
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• pp.605-610
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• 2008

This study was carried out to investigate the short-term (3 years) effect of thinning on aboveground carbon storage for 34-year-old (site 1) and 45-year-old (site 2) Korean pine (Pinus koraiensis Siebold et Zuccarini) plantations with different diameter class and site quality located in Gwangneung experimental forest. Thinning was manually carried out in consideration of basal area in 2004 (site 1 : 30% and 60% of basal area removed and site 2 : 60% of basal area removed). In 2004 and 2007, DBH and tree height were measured to analyze the changes in carbon storage after thinning. In the sites of 60% of basal area removed, although the mean DBH of site 1 was higher than that of site 2, mean annual carbon storage increment in site 2 ($6.5Mg\;C\;ha^{-1}yr^{-1}$) was about 3 times higher than that in site 1 ($2.3Mg\;C\;ha^{-1}yr^{-1}$). The reason for this result was probably due to higher stem density and site quality in site 2 compared to site 1. In site 2, mean annual carbon storage increment in thinned plot ($6.5Mg\;C\;ha^{-1}yr^{-1}$) was about 1.3 times higher than that in control ($5.2Mg\;C\;ha^{-1}yr^{-1}$). The results suggest that the stem density and site quality may be much more related to the aboveground carbon storage compared to diameter class. In addition, it is needed to consider these two factors for determining whether thinning is a feasible management alternative for the increase in aboveground carbon sequestration.