• Journal of Korean Society of Water and Wastewater
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• v.20 no.5
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• pp.727-736
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• 2006

Granular activated carbon (GAC) has been identified as a best available technology (BAT) by the United States Environmental Protection Agency (USEPA) for removal disinfection by-product (DBP) precursors, such as dissolved organic carbon (DOC) and dissolved organic nitrogen (DON). Rapid small-scale column test (RSSCT) were used to investigate four types of carbon (F400, Norit1240, Norit40S, and Aquasorb1500) for their affinity to absorb natural organic matter (NOM). DOC, $UV_{254}$, and Total dissolved nitrogen (TON) concentrations were measured in the column effluent to track GAC breakthrough. DOC and $UV_{254}$ breakthrough occurred at around 3500 bed volumes (BVs) of operation for all GACs investigated. The $UV_{254}$ breakthrough curves showed 33% to 48% at 8000 BVs, when the DOC was 48% to 65%. All GACs showed greater removal in DOC than $UV_{254}$. The NORIT1240 GAC was determined to have the highest adsorption capacity for DOC and $UV_{254}$. The removal of nitrate (NOTN) had not broken through over BVs. The initial TON breakthrough curves were started around 50%, when the DOC breakthrough was only 10 % at 500 BVs. The curves were gradually increased after 3500 BVs and approximately 69% through 81% of TON breakthrough occurred at 8000 BVs. All of the GACs were able to remove TON, in the case of this investigation the majority of the TON was present as DON. Because nitrate nitrogen was seldom removed and ammonium nitrogen ($NH_3-N$) was not detected in the effluent from RSSCTs even though raw water. The carbon usage rate of DOC was from 2 to 6 times less than that of TON. The NORIT1240 GAC demonstrated the best performance in terms of DOC removal, while the F400 GAC was best in terms of TON removal. Excitation emission matrix(EEM) analysis was used to show that GAC adsorption successfully removed most of Humic-like DOC and Fulvic-like DOCs. However, soluble microbial product(SMP)-like DOC in the absence of raw water were detected in the NORIT40S and Aquasorb1500 GAC. The authors assumed that this results is due probably to the part of GAC in the RSSCT which was converted into biological activated carbon(BAC). To compare with organics removal by GAC according to preloading, the virgin GACs had readily accessible sites that were adsorbed DOC more rapidly than preloaded GACs, but the TDN removal had not showed differences between those GACs.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.93-93
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• 2011

전 세계적으로 기후변화로 인한 기상재해의 피해가 매년 증가하고 있으며, 기후변화로 인한 시민들의 안전, 재산, 인명피해 또한 늘어나고 있다. 이러한 피해를 최소화하기 위해서는 도시지역을 중심으로 한 신뢰성 높은 미래 기후전망 기법이 필수적이며, 미래 기후전망을 바탕으로 하여 기후변화로 인한 향후 발생할 수 있는 위험성의 정도를 전망하여 적응대책을 수립할 필요가 있다. 본 연구에서는 도시지역의 미래 기후전망 기법을 개발하여 서울시의 미래기후를 전망한다. 본 연구를 수행하기 위하여 먼저 IPCC 기후시나리오에 대한 조사를 수행하여 자료를 수집한다. 수집한 자료를 바탕으로 역학적 상세화와 통계적 상세화 기법을 이용하여 고해상도 기후 시나리오를 생산하였다. 역학적 상세화 기법은 A2시나리오의 ECHO-G/S에서 생산된 기후 시나리오를 이용하여 지역 기후모델인 RegCM3에 적용하여 상세화 과정을 수행하였다. RegCM3를 이용하여 60km로 상세화한 후에 one-way double-nested system을 구축하여 20km까지 상세화 하였다. 20km 해상도의 기후 시나리오는 서울시와 같은 좁은 지역의 기후를 분석하기에는 어려움이 있으므로, RegCM3에 사용할 수 있는 Sub-BATS라는 기법을 이용하여 5km의 고해상도 기후 시나리오를 생산하였다. 역학적 상세화 결과는 관측결과에 비해 과소 추정되는 경향이 있어, 편차보정을 통하여 관측값에 가까운 자료를 만들어 주었다. 역학적 상세화 결과를 분석한 결과, 기준기간에 비해 미래기간(S3)에는 전체적으로 약 4.9도의 기온상승과 강수량 증가가 나타났으며, 특히 9월에 가장 큰 상승폭을 나타내고 있었다. 강수량의 경우 증가 경향이 뚜렷이 나타나고 있었으며, 여름철에 큰 증가폭을 나타내고 있었다. 통계적 상세화 기법은 역학적 상세화 기법에서 사용된 ECHO-G/S를 포함한 13개의 GCM결과와 우리나라의 57개 지점에 대한 CSEOF기법을 이용하여 기후 시나리오를 생산하였다. 이 자료는 서울시에 대하여 하나의 지점밖에 존재하지 않아, 서울시내의 지역별 미래 기후전망에는 문제가 있었으므로, Delta method라는 기법을 이용하여 서울 및 인근지역의 AWS 35개 지점에 대하여 미래 기후시나리오를 생산하였다. 통계적 상세화 결과, 13개 GCM의 기온변화는 전체평균 약 3.1도 상승하였고, 겨울과 여름철의 변화폭이 가장 크며, 모델의 불확실성 또한 겨울과 여름에 가장 큰 특징을 가지고 있다. 강수량의 경우 MME에서는 약간의 상승은 나타나고 있었지만 모델간의 불확실성은 여름철에 크게 나타나고 있었다. 역학적 및 통계적 상세화 기후 시나리오(ECHO-G/S, A2)를 비교 분석한 결과, 기온은 역학적 상세화 결과가 약간 크게 나타났으며, 전체적으로 유사한 패턴을 보이고 있었다. 강수량 또한 역학적 상세화 결과가 크게 나타나고 있었다. 역학적 및 통계적 상세화 결과는 S1의 경우 유사한 특징을 보이고 있었지만 S3로 갈수록 차이가 크게 나타나고 있었다.

• Childhood Kidney Diseases
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• v.11 no.2
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• pp.294-298
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• 2007

Moyamoya disease is a progressive cerebrovascular disorder with stenosis or occlusion of the bilateral internal carotid arteries with abnormal vascular networks at the base of the brain. Previous reports have shown that there are extracranial vascular involvements in Moyamoya disease, especially in the renal artery. We report a 7-year-old patient with Moyamoya disease associated with renovascular hyper tension, who presented in infancy with seizures and hemiparesis. Renal angiography showed multiple stenoses of the right renal artery. Although renal artery stenosis in Moyamoya disease has been effectively treated with balloon angioplasty, stent implantation, or surgery, bat-loon angioplasty could not be done in this patient due to multiple stenoses. His blood pressure was successfully controlled with medical treatment, and remained normotensive during the follow up period of 6 months.

• Therapeutic Science for Rehabilitation
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• v.6 no.1
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• pp.35-43
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• 2017

Objective : To identify the effect of symmetrical and asymmetric bilateral training For stroke patients in upper extremity recovery. Methods : 15 patients with stroke, randomized to an in- phase group(n =7) and anti-phase group(n =8). Each groups received symmetrical and asymmetric bilateral training, 30-min sessions per a day for 5 weeks, total 20 session.Accelerometer was used to evaluate the amount used for both groups. Y-BAT was used to evaluate performance status and satisfaction, ARAT was used to evaluate hand function. Results : the amount used of symmetrical movement training showed significant changes in affected and unaffected side. asymmetric bilateral training. there is a significant difference in affected side before and after receiving asymmetric bilateral training. Also, There was a significant difference between the groups on the affected side. Both training, there was no significant difference in performance, satisfaction, and upper limb function between group but, there was significant differences within-groups, Conclusions : Symmetric training showed higher motor performance than asymmetric training, but, To obtain a clearer difference, it would be necessary to use a neuromuscular assessment tool such as fMRI. Also, need a clearer training protocol and the need for follow-up studies on more stroke patients is suggested.

• Journal of Science Education
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• v.36 no.1
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• pp.153-165
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• 2012

This study investigated the frequent mistakes and the causes of the alternative conceptions in the animal classification by using the questionnaire and interview with the middle school students (N=300). As results, some students have difficulties classifying suggested animals into vertebrates or invertebrates : snakes (31.7%), shrimps (28.3%), turtles (25.6%), frogs (24.7%), and starfish (10.7%) in order of precedence. These errors seemed to be caused by intuitive thinking over characteristics of physical motions and appearance of suggested animals, wrong inference from comparing to features of familiar animals and the lack of observation experience of the vertebrate backbone. Furthermore, the results showed that relatively many students made a mistake classifying subgroup members of vertebrates such as classifying salamanders into the class Reptilia (45.3%) and turtles into Amphibia (40.3%). It is likely that those errors are affected by ambiguousness of classification terminology (e.g. the term of Amphibia) and weak ability in relating the physiological and ecological feature to standard of classification feature. In addition, sociocultural factors could influence animal classification as 'bat in birds', 'whale in fish, and 'penguin in mammals'. The present study implied that teaching and learning animal classification may require an appropriate guide focused on activities to explore major characteristics used for the animal classification standard through providing more chances of animal observation rather than the cramming method of learning induced by technical memorizing.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.5
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• pp.55-63
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• 2018

Recently, the use of duplex stainless steel which with a two-phase microstructure (equal mixture of ferrite and austenite) has been increased in a variety of industrial fields due to higher strength leading to weight saving, greater corrosion resistance(particularly, stress corrosion cracking) and lower price. However, currently, stainless steels are not included in the structural materials of Korean Building Code and corresponding design standards are not specified. In this paper, experimental studies have been performed to investigate the structural behaviors of duplex stainless steel (STS329FLD) bolted connection with two bolts for providing the design data. Main variables are shear connection type (single shear and double shear) and end distance parallel to the direction of applied force. Fracture modes at the final step of test were classified into typical block shear fracture, tensile fracture and curling. Curling occurrence in single shear connection led to ultimate strength drop by up to 20%. Test strengths were compared with those by current design specifications such as AISC/AISI/KBC, EC3 and AIJ and proposed equations by existing studies. For specimens with no curling, Clement & Teh's equation considering the active shear plane provided a higher strength estimation accurancy and for specimens with curling, Kim & Lim's equation considering strength reduction by curling was also overly unconservative to predict the ultimate strength of curled connections.

• Solar Energy
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• v.13 no.1
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• pp.1-10
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• 1993

The purpose of this research is to investigate the characteristics of heat transfer in the downward axisymmetric free water jet system impinged on a flat oblique plate which has the uniform heat flux. Experimental conditions considered were Reynolds number, distance between nozzle and Bat plate, inclination angle of heater surface and nozzle exit velocity. Local Nusselt number was subjected to the influence of Re number, Pr number, oblique angle of heating surface and local position of flat plate. In the wall region of downward surface, The secondary peak point of heat transfer appeared at the local point of X/D=-8 from the stagnation point. The stagnation heat transfer rate of this experimental study augments 2.4 times than that of laminar theorical solution. The stagnation nusselt number is function of Reynolds number, nozzle-plate spacing Prandtl number and oblique angle of impinging plate.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.33 no.3
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• pp.58-65
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• 2015

Compared to pavement of Chinese palace gardens, those of private gardens in south part of the Yangtze River(長江) in China shows variety of patterns. In order to figure out what causes the difference in paving pattern, this article focuses on the traditional Chinese ideologies during the all time. An analysis on 'Classical Gardens of Suzhou', which has been designated as UNESCO World Heritage, was used to determine how ideologies have influence on paving pattern of Classical Gardens. As a result, various Chinese ideologies such as Nature worship, Totemism, Confucianism, Taoism, Buddhism, and Folk Culture were found in paving patterns of the private gardens. Pattern of sun in the Retreat & Reflection Garden(Toisawon) is an example of Nature worship among primitive beliefs of ancient China. Phoenix pattern of the Couple's Retreat Garden(Ouyuan, Liuyuan) reflects Totemistic beliefs. Confucianism is the underlying philosophy of Eight Square pattern, Six Square pattern, and Cross Square pattern. These patterns were mainly used to pave large area and easily found in many gardens. Patterns reflect Taoism are "Wufu holding life" pattern(the Five blessing holding life, 五福捧壽), Flat peach pattern, and Alluding Eight Immortals pattern. Paving patterns related to Buddhism are patterns of 'Eight treasures' and Endless knot pattern appears most frequently since it expresses concept of reincarnation well. Paving patterns shows folk culture and beliefs of the time in China are bat, butterfly, dragonfly, frog, carp, and coin(ingot).

• Journal of Digital Convergence
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• v.18 no.8
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• pp.225-230
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• 2020

The KBO League is held over a long period of time due to the large number of games. Also, Korea has a diverse and distinct climate. Therefore, this study analyzed the relationship between the daily average temperature and the record of batting power such as home runs, triples, doubles, number of bases, batting percentage, and net batting percentage, and a third baseball record was defined. For this study, the correlation between the daily average temperature data and the batter who entered the standard at-bat in the KBO League in 2019 was analyzed through the SEMMA method. From the results of this study, it was found that the average daily temperature had an effect on a batter's hitting power. In particular, it was found that a batter's hitting power decreased on the day of temperatures recorded between 20.0 degrees and 24.9 degrees, and it was discussed that this may have been related to the physical condition of the pitcher the batter was facing. Therefore, it can be expected that players, coaching staff, and the front desk can use them in the game through conditions outside the game. In addition, it is expected that it will be a more useful analysis model by analyzing the records of pitching, base running, and defense as well as subsequent batting records.

• Korean Journal of Environment and Ecology
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• v.31 no.1
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• pp.30-41
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• 2017

Mammals in Korea have been studied in various fields such as animal science, veterinary medicine, laboratory animal science, ecology, and genetics. As the importance of biodiversity has been emphasized recently, conservation and management of mammals have attracted much public attention. However, in spite of such an increase in scientific research and public interest, it is still difficult to find a report or summary to grasp the trend of mammalian research in Korea. The purpose of this study is to provide the basic data for future plans of the detailed research area and the related policies by grasping the research trends of mammals in Korea. Using text-ming and co-word analysis, we analyzed 392 mammalian research papers published in Korean national journals as of 2015. Our results showed that the number of mammalian research papers published in Korea has gradually increased and that the research target species have also become increasingly diverse. The major research areas identified through text-mining and co-word analysis are (1) evolution/phylogenetics/genetics, (2) environmental science/ecology, (3) embryology/reproductive biology/cell biology, (4) veterinary medicine related to parasites, (5) parasitology related to rodents, (6) bacteriology/virology, (7) anatomy/cell biology/laboratory animal science, (8) veterinary science related to morphology and anatomy, (9) animal science, (10) marine mammalogy, and (11) Chiroptera (bat) research. Environmental science/ecology has been the most active field among the 11 research areas in recent times, and the proportion of research has increased sharply compared to the past. Environmental science/ecology is the core of biodiversity conservation, and as the importance of biodiversity has been emphasized in recent years, researchers' interest in mammal ecology appears to have increased. We expect that the results of this study will be useful for future research plan and related policies on mammals in Korea.