• Journal of Korean Society of Environmental Engineers
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• v.33 no.1
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• pp.25-31
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• 2011

In this study, model-based $NH_4-N$ predictive control algorithm by using influent pattern was developed and evaluated for effective control application in $A^2/O$ process. A pilot-scale $A^2/O$process at S wastewater treatment plant in B city was selected. The behaviors of organic, nitrogen and phosphorous in the biological reactors were described by using the modified ASM3+Bio-P model. A one-dimensional double exponential function model was selected for modeling of the secondary settlers. The effluent $NH_4-N$ concentration on the next day was predicted according to model-based simulation by using influent pattern. After the objective effluent quality and simulation result were compared, the optimal operational condition which able to meet the objective effluent quality was deduced through repetitive simulation. Next the effluent $NH_4-N$ control schedule was generated by using the optimal operational condition and this control schedule on the next day was applied in pilot-scale $A^2/O$ process. DO concentration in aerobic reactor in predictive control algorithm was selected as the manipulated variable. Without control case and with control case were compared to confirm the control applicability and the study of the applied $NH_4-N$control schedule in summer and winter was performed to confirm the seasonal effect. In this result, the effluent $NH_4-N$concentration without control case was exceeded the objective effluent quality. However the effluent $NH_4-N$ concentration with control case was not exceeded the objective effluent quality both summer and winter season. As compared in case of without predictive control algorithm, in case of application of predictive control algorithm, the RPM of air blower was increased about 9.1%, however the effluent $NH_4-N$ concentration was decreased about 45.2%. Therefore it was concluded that the developed predictive control algorithm to the effluent $NH_4-N$ in this study was properly applied in a full-scale wastewater treatment process and was more efficient in aspect to stable effluent.

• Archives of design research
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• v.17 no.3
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• pp.221-230
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• 2004

Design textbooks for general education bring our attention to the education of design as a part of whole education. In this vein, this thesis tried to analyze and discuss on the current status of design education contents included in the 7th educational curriculum of the Art & Life. This study had a historical review of the contents of arts education as well as a review of theoretical contents in art education. Also this thesis analyzed five types of Art & Life text books currently used at high schools with weight given to the design and to the status of pictorial coverage in the text books. Finally, the thesis presented problems of design education through a comparative analysis of high school arts education and design education. Through the analysis, inequality of design contents in education was reported. It was clearly attributable to the backgrounds of text book writers. For example, authors with graphic design backgrounds tended to lack product and environment design concepts, while hand craft section of text books all showed a biased contents towards traditional Korean arts. In the analysis of pictorial coverage, similar to the composition of academic contents, coverage was concentrated in the graphic design areas; inequality in quantity of pictures found with a ratio of 1 to 4. In terms of areas of arts, design contents in text books were concentrated only in arts creation chapters among the 3 major areas of arts appreciation, understanding, and creation. Design education is attained in an atmosphere of creativity and the provision of ample teaching material. It is because diverse contents will generate the development of arts. When compared to design education curriculum of U.S. and Japan, these creativity put their focus of design education in the understanding and emotional contacts, so that every application is easily attained. In terms of expression learning, creativity and diversity of material are emphasized. From Kindergarten to middle, and high school periods, apparently the care contents of deign is emphasized. A textbook in the 7th education curriculum is one of the sources for education. In designing text books, learning process should be emphasized following subjects and natures of arts so that creativity can be achieved. Therefore, a systematic approach for design research and educational development for material would be needed in textbook design.

• Journal of Nutrition and Health
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• v.50 no.1
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• pp.64-73
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• 2017

Purpose: Excess sodium intake may contribute to the etiology of hypertension and cardiovascular disease risk. World Health Organization (WHO) recommends a daily sodium intake of less than 2 g. The aim of this study was to estimate the association of sodium intake with obesity in Korean adults. Methods: This study used Dietary intake and Health data on 22,321 subjects aged 30 years and over from the Korea National Health and Nutrition Examination Survey (KNHANES) 2010~2014. Information on dietary intake was obtained by the one day 24-hour recall method in KNHANES, and sodium intake was classified into five groups (< 2,000 mg, 2,000~4,000 mg, 4,000~6,000 mg, 6,000~8,000 mg, ${\geq}8,000mg$). Obesity was defined as having a body mass index (BMI) higher than $25kg/m^2$. Intake of sodium and obesity status were analyzed by logistic regression with SPSS Statistics 23. Results: Men tended to have a higher sodium intake than women (p < 0.001). After adjusting for age, sex, year, daily energy intake, education level, smoking status, drinking status, physical activity, and chronic diseases and comparing the highest sodium intake group (${\geq}8,000mg$) with the lowest intake group (< 2,000 mg), the OR of obesity was 1.351 (95% CI: 1.032~1.767) in men. The OR of obesity in the sodium intake group (4,000~6,000 mg) was 1.232 (95% CI: 1.063~1.427) in women. Conclusion: Our findings suggest an independent relationship between sodium intake and as increased risk of obesity in Korean adults, implying the necessity for future research on low-sodium diet intervention in relation to obesity.

• Korean Journal of Agricultural and Forest Meteorology
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• v.2 no.4
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• pp.183-189
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• 2000

This study was carried out to analyze ecophysiological responses for seedling of Quercus serrata, Quercus mongolica and Quercus variabilis that are the typical species of deciduous broadleaved forests in Korea. And executed experiments in the climatic control room to provide necessary information to ecological forest management and methods of natural regeneration through the analysis of seedling responses. The details of experimental analysis were growth processes of 4 months after seeding that vary with the condition of three light intensity[relative light intensity(RLI) 8%, 20%, 52%] and three soil moisture[water suction(WS) Ψ=100 hPa, Ψ=280 hPa, Ψ=330 hPa] gradient, growth factors after harvesting and the nutrition condition of leaves. The results of this study are followings: 1) Early growth was prosperous after germination for the species which have more weight of acorn. 2) The formation of lammas shoot was favourable with Q. variabilis and Q. mongolica. And the rate of the occurrence was the highest in the RLI 20%, and it was remarkably reduced in the RLI 8%. 3) As the height growth of seedling of all 3 species were greater in the RLI 20% and 8% than that of the RLI 52%, they showed strong shade tolerance. 4) The increase of light intensity promoted the diameter at root collar growth, and development of main and lateral roots with all 3 species. 5) It showed that the increase of light intensity in the experimental radiation condition raised special leaf area weight(mg/cm$^2$) and leaf area productivity(mg/cm$^2$). Consequently, these resulted in the increase of leaf thickness and total dry biomass per the unit area of leaf. 6) As the increase of light intensity, the minerals contents of leaves such as N, P and K were lowered, and the increase of soil moisture resulted in the increase of P, K, Ca and Mg.

• The Journal of Korean Physical Therapy
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• v.16 no.1
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• pp.140-156
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• 2004

This study, to find whether a sports activity and a speciality aptitude activity in school-childhood can affect in forming E.Q, has been done in Gyoung-Nam area and Busan wide city with asked 222 of men and women being in their school-childhood and a group of 85 people who had not joined in such activity, using a E.Q testing paper provided by Dae-Gyo Education Corp,. and Seoul National University Educational Research Institute. Following is the results after analyzing the compiled datas. 1. The E.Q. level difference between people who joined, and who not joined in a sports action activity was reported existing, the total E.Q average of those who joined was resulted 212.6, a point 29.6 higher than those not joined of 183.0 ( p< .05). As for the E.Q causing points, it resulted that the points of the joined group is generally up than that of the non-joined group, especially this difference was remarkable in terms of feeling recognition or feeling control, a finding that deserves an attention ( p<.05) 2. Joining periods of sports activity did also have relation to develping E.Q. of school-childhood according to this research, the total E.Q points of a group joined in the activity more than 2 years was 215.5 points, which was 17.4 points higher than those not joined of 186.5 points ( p< .05). Backing again to E.Q causing points in this case, it resulted without exeption of all main causes that those who joined in more than 2 years are generally higher than that of those joined less than 2 years, especially the difference was regarded as big in terms of feeling recognition or feeling control, a finding that deserves an attention ( p<.01). 3. The E.Q. differnce between those joined in a specialty aptitude activity and not joined was studied existing, the total E.Q average points of those joined in a specialty aptitude activity was 207.8, a higher figure by 21.3 points than those not joined group of 186.5 ( p< .05). As for the E.Q causing points, it resulted without exeption of all main causes that those who joined are generally higher than that of those not joined, especially for feeling recognition or feeling control, this difference was more clear, a finding that deserves an attention ( p<.01). 4. It also resulted that E.Q growth depends on the periods to have joined in a speciality aptitude activity, for example, the total E.Q points of those joined in the activity more than 2 years was 217.1, a total more higher by 13.5 points than 203.6 of those not joined ( p< .05). For the E.Q. causing points, it, with the exception of empathy was resulted that those who joined in the speciality aptitude activity more than 2 years are generally higher than those joined less than 2 years, especially the difference is remarkable in terms of feeling recognition or feeling control, a finding that is also remarkable ( p<.05). 5. The E.Q difference between the men and women who joined in both activities of sports & speciality aptitude was found existing, the total E.Q. average for women was resulted 214.2 points, which was 9.2 points higher than men of 205.0. As for the E.Q. causing points, which, without exeption of main causes, women's was reported being high than that of men, in special is more remarkable in terms of feeling control, a finding that deserves an attention. ( p<.05).

• Korean Journal of Veterinary Research
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• v.33 no.4
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• pp.657-664
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• 1993

To reveal the immunogenicity of ${\gamma}-irradiated$ E tenella and its progeny, a series of experiments on the effects of Cobalt-to ${\gamma}-irradiation$ was performed. The SPF chickens inoculated with diffenrt doses of inoculum were challenged with $1{\times}10^5$ oocysts of virulent E tenella. The levels of 100 Gy ${\gamma}-irradiation$ from $^{60}Co$ and of inoculum with $1{\times}10^4$ oocysts were recognized as proper as immunogen by comparison of survival rates, body weight gains, blood in feces and lesion scores in the chickens. In these trials of challenge with virulent E tenella after inoculation with $1{\times}10^4$ oocysts of the ${\gamma}-irradiated$ E tenella and its progeny, the survival rates of the chickens challenged with the virulent E tenella after immunization with the 1st and the 3rd progeny groups of ${\gamma}-irradiated$ E tenella oocysts were higher(l00%) than that(87.0%) of the challenged control group. The signs of blood in feces and the lesion scores were seen markedly lower with the ourput of the smaller number of oocysts, i.e. OPG 103,900 and 25,800 in the groups of the 1st and the 3rd progeny, respectively, than those(OPG 1,658,900) of the challenged control group. The body weight gains of the 1st and the 3rd progeny groups, the 1st week and the 2nd week after challenge, were higher (2.6g and 155.4g, 11.6g and 168.9g respectively) than those(-85.8g and 63.6g, respectively) of the challenged control group, and the feed conversion ratios(FCR 3.28 and 2.96) of the 1st and the 3rd progeny groups were lower than that(FCR 5.60) of the groups challenged control group. The anticoccidial indices(70.5 and 93.9) of the groups challenged with the virulent oocysts of E tenella after immunization with the 1st and the 3rd progeny of the ${\gamma}-irradiated$ E tenella were significantly higher than that (ACI -81.9) of the challenged control group. It was thought that the immunogenicity of ${\gamma}-irradiated$ E tenella would be increase according to increase the number of generation passaged in chicken. That might be because of increasing the pathogenicity of ${\gamma}-irradiated$ E tenella according to increase the number of generation passaged in chicken.

• Korean Journal of Ecology and Environment
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• v.35 no.3 s.99
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• pp.152-159
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• 2002

The seasonal variations of nitrifying bacterial population sampled from 3 sites in Moon-Chon reservoir were analyzed by in situ hybridization with fluorescently labeled rRNA-targeted oligonucleotide probes from August 2000 until July 2001. In addition, physico-chemical parameters such as temperature, pH, chi-a and DOC were measured to determine correlations between those factors and the size of nitrifying bacterial populations. Total bacterial numbers varied in the range of $0.8{\sim}1.5{\times}10^6\;cells/ml$ independent of sites and had the maximal values in March at all 3 stations. The ratio of eubacteria to total bacteria ranged from 44.9% to 79.5%, and the ratio of each nitrifying bacteria to eubacterial numbers reached only $1.0{\sim}7.4%$. The variations of ammonia-oxidizing bacteria ranged from $1.1{\times}10^4$ to $3.0{\times}10^4\;cells/ml$ without noticeable peak values whereas those of nitrite-oxidizing bacteria varied in $1.3{\sim}5.7{\times}10^4\;cells/ml$ with the increasing tendency in winter regardless of the sites. Moreover it was observed that the numbers of nitrite-oxidizing bacteria were higher than those of ammonia-oxidizing bacteria. Total bacterial numbers correlated with water temperature (r = 0.355, p<0.05) and DOC (r = 0.58G, p<0.01) positively whereas nitrite-oxidizing bacteria correlated with temperature (r = -0.416, p<0.05) and pH (r = -0.568, p = 0.001) negatively. In addition, DOC represented good correlations with eubacterial numbers (r = 0.448, p<0.01). These results indicate that temperature, DOC and pH might be one of the main factors affecting variations of bacterial populations in the aquatic ecosystem. It was also suggested that FISH method is a useful tool for detection of slow growing nitrifying bacteria.

• Korean Journal of Ecology and Environment
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• v.42 no.1
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• pp.9-18
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• 2009

The objectives of this study were to evaluate seasonal and interannual variations of water quality and nutrient input (N, P) in Junam Reservoir, a nesting waterbody of migratory birds, over 10 years during 1998$\sim$2007 along with dynamic relations of trophic parameters using empirical models. Concentrations of COD averaged 7.8 mg $L^{-1}$ during the study, while TN and TP were $1.4\;mg\;L^{-1}$ and $83{\mu}g\;L^{-1}$, respectively, indicating an eutrophic-hypereutrophic state. Values of monthly COD had strong positive relations (r=0.669, p<0.001) with conductivity, indicating that summer rainfall resulted in an ionic dilution of the reservoir water by rainwater and contributed better water quality. One-way ANOVA tests showed significant differences (F=$5.2{\sim}12.9$, p<0.05) in TN and TP between the before and after the bird migration. In other words, nutrient levels were greater in the absence of migratory birds than in the presence of the migratory birds, suggesting a no-effect on nutrient inputs by the birds. Also, one-way ANOVA indicated no significant differences (F=$0.37{\sim}0.48$, p>0.05) in $NO_{3^-}N$ and $NH_{3^-}N$ between the before and after the birds migration. Linear empirical models using trophic parameters showed that algal biomass as CHL, had significant low correlations with TN ($R^2$=0.143, p<0.001, n=119) and TP ($R^2$=0.192, p<0.001, n=119). These results suggest that influences of nutrients on the CHL were evident, but the effect was weak. This fact was supported by analysis of Trophic State Index Deviation (TSID). Over 70% in the observed values of "TSI (CHL)-TSI (SD)" and "TSI (CHL)-TSI (TP)" were less than zero, suggesting a light limitation on the CHL by inorganic suspended solids.

• Horticultural Science & Technology
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• v.33 no.5
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• pp.638-646
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• 2015

To increase the utility of seeds in plant resources, seeds of 6 Aster species(A. incisus, A. hayatae, A. koraiensis, A. scaber, A. spathulifolius, and A. yomena) were subjected to experiments to develop adequate methods for sprout production. To study optimum germination conditions, germination rates of the seeds were analyzed at different temperature (15, 20, 25, and $30^{\circ}C$) and light conditions. A longitudinal growth experiment was performed in dark conditions for 10 days. Seedlings, with optimum germination rate and longitudinal growth, were placed in the light for 0-3 days to seek the adequate greening periods. Sprouts grown under optimum environmental conditions were placed in vessels with or without ventilation, and stored under $4^{\circ}C$ and $10^{\circ}C$ to examine storage environment and period. As a result of this analysis, seeds were selected that germinated over 50% within 12 days. Longitudinal growth was promoted at $20-25^{\circ}C$, and optimum growth was obtained with 7-9 days. As greening days increased longitudinal growth was retarded, but orbital growth of radicles and cotyledons was promoted. Considering all these factors, greening treatment of 2 days showed the best results. In a storage ability experiment, the best result was achieved by storage in vessels without ventilation under $4^{\circ}C$. Ventilation prevented rotting of sprouts, but reduced moisture contents of sprouts. Most sprouts were fresh at $4^{\circ}C$ for 3-6 days. In particular, sprouts of A. hayatae and A. yomena had high keeping quality, and remained fresh over 3 days even at $10^{\circ}C$.

• Proceedings of the KSCN Conference
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• 2003.11a
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• pp.1051-1052
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• 2003

미취학 아동기는 생후 1년 동안의 급격한 성장 이후로부터 학령기가 되기 전까지 성장이 완만해지는 시기이다. 이 시기의 아동들은 혼자 먹는 행동을 익히게 되고 식품에 대한 기호가 형성되는 등 식생활에서도 뚜렷한 개인특성을 갖게되며 이 시기에 형성된 식습관은 성인까지 이어지게 된다. 이 시기에 영양부족에 따른 신체발달의 지연이나 영양과잉에 따른 비만과 같은 과다한 신체발달의 문제점이 지적되고 있어 올바른 식습관 형성은 신체발달과 밀접한 관련성이 있는 것으로 보여진다. 우리나라는 취약한 칼슘섭취 부족에 따라 골격건강에 대한 관심이 크게 증가하고 있는데, 모든 질환이 그러하듯이 골격질환도 치료보다는 예방적인 관리가 다양한 측면에서 효율적이다. 따라서 골격건강과 최적의 신체발달을 위한 식사인자는 매우 중요하며, 일생의 성장시기에 따라 서로 다른 인자들이 관여할 것으로 생각된다. 이에 본 연구에서는 성장이 이루어지면서 식품선택의 독립성이 확립되는 미취학 아동에 있어 신체와 골격 발달에 관련성이 있는 영양섭취 요인을 찾아봄으로써 골격과 신체 발달을 위한 올바른 식습관 형성에 필요한 기초자료를 제시하고자 하였다. 이에 46~84개월의 미취학 어린이 총 62명(남자 37명, 여자 25명)을 대상으로 어머니에 의한 설문조사를 실시하고 대상자의 신체계측(InBody, Biospace)과 손목의 골밀도(DEXA, Medilink)를 측정하였다. 설문지는 어린이와 부모의 일반사항, 어린이의 건강상태, 식습관 및 활동조사표와 24시간 회상법에 의한 식사조사표로 구성하였다. 식사섭취조사 결과는 CAN-Pro를 이용하여 영양소 섭취량을 분석하였으며, 모든 연구결과는 SAS program을 이용하여 통계 분석하였다. 연구결과를 요약하면 다음과 같다. 남녀 어린이의 평균 월령은 62.43$\pm$7.26 개월과 62.12$\pm$8.85개월이었다. 출생시 신장과 체중은 남자 어린이가 50.92$\pm$2.14 cm와 3.36$\pm$0.42kg, 여자 어린이는 각각 50.29$\pm$1.36cm와 3.32$\pm$0.39kg이었다. 현재 신장과 체중은 남자 111.65$\pm$5.44 cm와 19.60$\pm$3.52kg, 여자 109.04$\pm$5.04 cm와 18.67$\pm$2.81kg이었으며, 비만지수는 남녀 각각 -2.13$\pm$9.09%와 0.22$\pm$10.49%였다. 손목의 골밀도는 남녀 어린이 각각 0.25$\pm$0.04g/cm, 0.24$\pm$0.03g/$\textrm{cm}^2$이었다. 에너지 섭취량은 남녀 어린이 각각 영양권장량의 66.43$\pm$18.58%와 70.46$\pm$20.31% 수준이었으며, 남녀 어린이 모두 단백질(124.97$\pm$37.55%, 131.24$\pm$45.49%), 비타민B$_{6}$ (152.48$\pm$47.01%, 152.95$\pm$61.77%), 엽산(106.87$\pm$40.44%, 104.52$\pm$50.16%), 비타민 E (121.04$\pm$52.79%, 113.48$\pm$75.78%)를 제외한 영양소 섭취량이 권장량에 미달되는 섭취수준을 보였다. 특히 성장기에 중요한 칼슘도 남녀 어린이 각각 권장량의 62.21$\pm$39.46%와 70.07$\pm$34.52%로 낮게 섭취하고 있었다. 모든 영양소 섭취량은 남녀 어린이간에 유의한 차이가 없었다. 신체계측치와 영양섭취와의 관계에서 체중, 체수분량, 제지방량은 각각 동물성 철 섭취량과 유의한 부의 상관관계를 보였다(p<0.05, p<0.01, p<0.01). 골밀도와 영양섭취와의 관계에서 손목 골밀도는 식물성 칼슘 섭취량과 유의한 정의 상관관계를 보였고(p<0.05), 특히 위쪽 손목 골밀도는 동물성 단백질, 동물성 철 섭취량과 각각 유의한 부의 상관을 보였다(p<0.05, p<0.05). 이상의 연구결과를 종합할 때 성장이 진행되고 있는 미취학 아동에 있어 신체상태와 골밀도는 동물성 단백질, 식물성 칼슘, 동물성 철 섭취량과 상관성이 있는 것으로 나타남으로써 앞으로 이들 영양소의 섭취가 신체와 골격 성장에 어떠한 영향을 미치는가에 대한 보다 세부적인 연구가 이루어져야 할 것으로 생각된다.