• Proceedings of the Korea Water Resources Association Conference
• /
• 2005.05b
• /
• pp.1148-1153
• /
• 2005

하수관거는 국민의 정맥이라고 할 수 있을 정도로 도시의 환경관리와 치수, 쾌적한 환경조성에 있어서 매우 중요한 시설이며 그 규모가 광범위하고 복잡한 네트워크로 구성되어 있다. 이러한 하수관망을 통해 이송되는 물은 지저분하고 냄새가 심하기 때문에 지하에 관의 형태로 대부분 시공되어 왔으며, 상수관망처럼 압력관이 아니라 대부분 중력에 의한 이송방식을 채택하고 있어 문제 발생 시 원인파악과 대처를 힘들게 하는 요인을 가지고 있다. 특히 하수관거의 관리 소홀은 곧바로 토양오염과 인근 환경오염으로 직결되며 장기적으로는 상수를 오염시키는 요인으로 작용하므로 체계적인 방법과 장기적인 안목을 가지고 명확한 분석을 시행할 수 있는 시스템을 가지고 최적으로 유지관리 되어야 한다. 최근 들어 이러한 하수도 시설을 효율적으로 관리 및 개선하기 위해 대도시를 중심으로 근거 조사와 정비 사업이 활발히 시행되고 있다. 그러나, 사업효과를 검증하거나 관로의 유지관리를 위하여 국내 실정에 맞지 않는 외국하수관망 흐름 해석 프로그램을 그대로 사용하고 있고 정확한 해석이 이루어지지 않고 있어 효율적인 유지관리가 어렵다. 이와 같은 문제점을 해결하기 위하여 하수관망해석이나 하수관망 정비시 필요한 불명수산정이 가능하고 국내실정에 맞는 프로그램 개발이 시급한 실정이며, 아울러 프로그램을 효율적 운영하고 관리하는 제어관리 기술을 개발, 진행하고 있다. 본 논문에서는 개발된 프로그램의 부정류 해석 기능을 활용하여 대상구역의 해석을 실시하여 기존분석방법의 I/I결과와 비교하였으며 최적관리를 위한 방안을 제시하였다.준편차가 증가하고 있음을 알 수 있다. 본 연구에서는 상용 CFD모형인 FLOW-3D를 계획 중인 하수처리장의 침전지 유입부 설계에 적용하였으며 저류벽의 위치와 폭, 유공정류벽의 유공율에 따른 유입하수의 분배효과를 분석하였다. 실험을 수행하여 보다 정밀한 공식으로 개선할 수 있었다.$10,924m^3/s$ 및 $10,075m^3/s$로서 실험 I의 $2,757m^3/s$에 비해 통수능이 많이 개선되었음을 알 수 있다.함을 알 수 있다. 상수관로 설계 기준에서는 관로내 수압을 $1.5\~4.0kg/cm^2$으로 나타내고 있는데 $6kg/cm^2$보다 과수압을 나타내는 경우가 $100\%$로 밸브를 개방하였을 때보다 $60\%,\;80\%$ 개방하였을 때가 더 빈번히 발생하고 있으므로 대상지역의 밸브 개폐는 $100\%$ 개방하는 것이 선계기준에 적합한 것으로 나타났다. 밸브 개폐에 따른 수압 변화를 모의한 결과 밸브 개폐도를 적절히 유지하여 필요수량의 확보 및 누수방지대책에 활용할 수 있을 것으로 판단된다.8R(mm)(r^2=0.84)$로 지수적으로 증가하는 경향을 나타내었다. 유거수량은 토성별로 양토를 1.0으로 기준할 때 사양토가 0.86으로 가장 작았고, 식양토 1.09, 식토 1.15로 평가되어 침투수에 비해 토성별 차이가 크게 나타났다. 이는 토성이 세립질일 수록 유거수의 저항이 작기 때문으로 생각된다. 경사에 따라서는

• The Korean Journal of Zoology
• /
• v.31 no.4
• /
• pp.327-333
• /
• 1988

계절에 따른 초파리 집단내 역위다형 현상의 변동상을 알기 위하여 전주근교의 과수원에서 1983년 1월부터 11월까지 격월로 여섯번 채집한 집단 표본을 분석하였다. 총 1071마리에서 얻은 15개형의 역위는 모두 편동원체역위(paracentric inversion)였으며, 이 중 7개형은 세계형91위(cosmopolitan inversion)였고, 나머지 8개형은 지역형역위(endemic inversion)였다. 개체당 역위의 평균 보유수는 0.639이고 역위를 보유한 개체의 빈도는 0.465였다. 7개의 세계형역위에 대한 표본집단을 분석한 결과 격월 집단간에서 유의한 차이를 보이는 반면 1월과 1 1월 표본간에서는 그 성황이 오히려 비숫해짐으로서 집단내 총역위빈도는 주기적으로 변동하고 있음이 암시된다. 역위와 환경변수와의 다중상관분석에서는 기온, 습도, 강수량이 역위빈도에 유의한 영향을 미치는 것으로 나타났고 역위 중 In(2L)t가 상기한 환경변수 모두에 대하여 유의한 상관관계를 보인 반면, In(3R)C와 In(3R)P는 어느 것과도 상관성을 보이지 않았다. 염색체내 그리고 염색체간의 연관 또는 조합의 검정결과 연관불평형혈상을 1월, 5월, 그리고 7월 표본의 제3염색체에서, 그리고 비균일조합은 1월과 7월 표본에서 역시 제3염색체에서만 산출 되었다. Seasonal changes of inversion frequencies in Chonju 0. melanogaster populations were studied. A total of 1071 males were collected six times with ho months intewal from January through November in 1983. to analyse diploid sets of chromosomes carried by males, each male was mated to several virgin females homoBvgous for cytologically standard sequence in all chromo-somes. From each mating, more than seven FL larvae were selected in random and tested to find chromosomal aberrations. In the present study, 15 different inversions were found and identified to be paracentric only In both second and third chromosomes; seven were cosmopolitan and the rest eight endemic types. The average frequency of inversions was 0.465 and the mean number of inversions carried by a single male was 0.639. The linkage disequilibria were detected between the leK and right arms of third chromosomes from the samples of January, May and Julv, Whereas nonrandom associations appeared also in the third chromosomes only in January and Julv samples. In multiple regression analysis among frequencies of inversions and environ-mental variables it appeared that mean temperature, relative humidity and total precipitation for a month skipped over 30 days before collected affect to change to frequencies of particular inver-sions. With respect to the behavior of inversions in the present samples, it is suggested, with the Friedman's analysis of variance by ranks of inversion frequency orders, that the frequencies of inversions change cyclically year to year.

• Microbiology and Biotechnology Letters
• /
• v.34 no.1
• /
• pp.63-69
• /
• 2006

We isolated a bacterium which produces antifungal substances from the Lake of Saimaa soils in Fin-land. The isolated strain was identified as Bacillus sp. and shown a strong antifungal activity on plant pathogenic fungi. Bacillus sp. KMU-1011 produced maximum level of antifungal substances under incubation aerobically at $24^{\circ}C$ for 48 hours in nutrient broth containing 1.0% glucose and 1.0% polypeptone at 180 rpm and initiated pH adjusted to 6.0. Precipitate of culture broth by $30{\sim}60%$ ammonium sulfate precipitation exhibited strong antifungal activity against Botrytis cinerea KACC 40573 by dry cell weight. Chloroform extract of cultured broth also shown fungal growth inhibitory activity against C. gloeosporioides KACC 40804, D. bryoniae KACC 40669, F. oxysporum KACC 40037, F. oxysporum KACC 40052, F. oxysporum f. sp. radicis-lycopersici KACC 40537, F. oxysporum KACC 40902, M. cannonballus KACC 40940, P. cambivora KACC 40160, R. solani AG-1 KACC 40101, R. solani AG-4 KACC 40142, and S. scleotiorum KACC by agar diffusion method.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.4
• /
• pp.454-462
• /
• 2018

This study was conducted to examine SNS addiction proneness and interpersonal satisfaction among undergraduate students and the relationships between these two variables, as well as to establish baseline data for appropriate intervention of SNS addiction prevention. The participants of this study were 316 undergraduate students in D and K city, and data were collected between June 30 and July 30, 2017. Data were collected by a self-administered online survey and analyzed by descriptive statistics, t-tests, and Pearson's correlation coefficients using SPSS. The results showed that SNS addiction proneness and interpersonal satisfaction were negatively correlated (r=-0.57, p<0.01), indicating students with higher SNS addiction had lower interpersonal satisfaction. There were no significant differences in SNS addiction proneness and interpersonal satisfaction by gender (t=0.05, p=0.963), number of SNS networks (t=0.66, p=0.513), or number of SNS-only networks (t=-1.24, p=0.216). Students who used SNS for data collection showed significantly higher interpersonal satisfaction (t=3.02, p=0.030); however, there was no significant differences in SNS addiction proneness among purposes for using SNS (t=0.39, p=.759). The results of this study will be useful baseline data for developing an intervention to improve interpersonal satisfaction and prevent SNS addiction among undergraduate students.

• Journal of Korea Water Resources Association
• /
• v.53 no.4
• /
• pp.273-283
• /
• 2020

Quantitative forecasting of groundwater levels for the assessment of groundwater variation and vulnerability is very important. To achieve this purpose, various time series analysis and machine learning techniques have been used. In this study, we developed a prediction model based on LSTM (Long short term memory), one of the artificial neural network (ANN) algorithms, for predicting the daily groundwater level of 11 groundwater wells in Hankyung-myeon, Jeju Island. In general, the groundwater level in Jeju Island is highly autocorrelated with tides and reflected the effects of precipitation. In order to construct an input and output variables based on the characteristics of addressing data, the precipitation data of the corresponding period was added to the groundwater level data. The LSTM neural network was trained using the initial 365-day data showing the four seasons and the remaining data were used for verification to evaluate the fitness of the predictive model. The model was developed using Keras, a Python-based deep learning framework, and the NVIDIA CUDA architecture was implemented to enhance the learning speed. As a result of learning and verifying the groundwater level variation using the LSTM neural network, the coefficient of determination (R²) was 0.98 on average, indicating that the predictive model developed was very accurate.

• Journal of Korean Society of Transportation
• /
• v.33 no.4
• /
• pp.393-404
• /
• 2015

Gravity model has had the major problem that the model explains the characteristics of travel behavior with only deterrence factors such as travel time or cost. In modern society, travel behavior can be affected not only deterrence factors but also zonal characteristics or transportation service. Therefore, those features have to be considered to estimate the future travel demand accurately. In this regard, there are two primary aims of this study: 1. to identify the characteristics of inter-zonal travel, 2. to develop the new type of calibration method. By employing accessibility variable which can explain the manifold pattern of trip, we define the zonal travel behavior newly. Furthermore, we suggest 2-phase calibration method, since existing calibration method cannot find the optimum solution when organizing the deterrence function with the new variables. The new method proceeds with 2 steps; step 1.estimating deterrence parameter, step 2. finding balancing factors. The validation results with RMSE, E-norm, C.R show that this study model explains the inter-zonal travel pattern adequately and estimate the O/D pairs precisely than existing gravity model. Especially, the problem with estimation of short distance trip is overcomed. In conclusion, it is possible to draw the conclusion that this study suggests the possibility of improvement for trip distribution model.

• Journal of Conservation Science
• /
• v.29 no.4
• /
• pp.345-354
• /
• 2013

This study analyses geochemistrical, microscopic, mineralogical characteristics of coals which have been collected from in and out of the shipwreck No 1 of Mado island during underwater excavation in Taean. The result from mineralogical and geochemical analysis reveals that the specific gravity of the coals is $1.28g/cm^3$. Considering that coals contains 10% mineral of it and the specific gravity of the pure is $1.15g/cm^3$, it is believed that the collected coals would be lignite or biturminous coal. The X-ray diffraction analysis which displays the peak of $2{\theta}$ is 20~25C degree, proves that the collected coals would be categorised as low rank coal. The collected coals is composed of: 93%-94%(93.5%) of vitrinite maceral group, 5%-6%(5.5%) of exinite maceral group, and 1% of inertinite maceral group. In addition, the average of reflection rate is $R_{mean}$: 0.627 showing that it would be either high volatile bituminous C coal or sub-bituminous C coal. Such result confirms that the coal is sub-bituminous C or high volatile bituminous C coal in accordance with the U.S Bureau of Mine(USBM) classification system. The element analysis reveals that the coal is the coking coal which is grouped as the bituminous coal. Comparative analysis between the coals of Mado Shipwreck No 1 and domestic coals shows that the coals of Mado Shipwreck is similar to the bituminous coal used in the area of Janggi in Pohang city.

• Journal of KIISE:Information Networking
• /
• v.30 no.4
• /
• pp.559-571
• /
• 2003

ENUM(tElephon NUmbering Mapping) is protocol that brings convergence between PSTN Networks and IP Networks using a unique worldwide E.164 telephone number as an identifier between different communication infrastructure. The mechanism provides a bridge between two completely different environments with E.164 number; IP based application services used in PSTN networks, and PSTN based application services used in IP networks. We propose a new way to organize and handle ENUM Tier 2 name servers to improve performance at the name resolution process in ENUM based application service. We build an ENUM based network model when NAPTR(Naming Authority PoinTeR) resource record is registered and managed by area code at the initial registration step. ENUM promises convenience and flexibility to both PSTN and IP users, yet there is no evidence how much patience is required when users decide to use ENUM instead of non-ENUM based applications. We have estimated ENUM response time, and proved how to improve performance up to 3 times when resources are managed by the proposed mechanism. The proposition of this thesis favorably influences users and helps to establish the policy for Tier 2 name server management.

• Food Engineering Progress
• /
• v.21 no.2
• /
• pp.132-137
• /
• 2017

The purpose of this study was to optimize dough properties using response surface methodology (RSM) and to demonstrate the performances of dough prepared under optimized conditions. Dough mixed with yeast, margarine, salt, sugar and wheat flour was prepared by fermentation process. Hardness, cohesiveness and springiness of dough were selected as critical quality attributes. The critical formulations (yeast and water) and process (fermentation time) variables were selected as critical input variables based on preliminary experiment. Box-Behnken design (BBD) was used as RSM. As a result, the quardratic, the squared and the linear model respectively provided the most appropriate fit ($R^2$>90) and had no significant lack of fit (p>0.05) on critical quality attributes (hardness, cohesiveness and springiness). The accurate prediction of dough characteristics was possible from the selected models. It was confirmed by validation that a good correlation was obtained between the actual and predicted values. In conclusion, the methodologies using RSM in this study might be applicable to the optimization of fermented foods containing various wheat flour and yeast.

• Journal of the Korean association of regional geographers
• /
• v.3 no.1
• /
• pp.183-198
• /
• 1997

This case study was conducted by verification the site characteristics based on the questionnaire and interview obtained from the all factories located at No. 1 developing area in Kumi industrial complex. The site characteristics were presumed from the process of location behavior and spatial linkage. Kumi industrial complex was developed to improve export industry at national levels by providing chief land price and benefiting various tax. Kumi industrial complex which enticed many factories is playing an important role in export industry in Korea. At beginning, the detention of large enterprises promoted the establishment of related small to medium sized factories into the complex. Two distinctive industries. textile and electronic, were reflected by the purpose to establish the complex and industrial characteristics of Taegu city. respectively. In Kumi industrial complex, positive responses on traffic and raw material supply and negative reactions on the environmental impact on social community as well as high labor charge were investigated. Especially the higher labor cost prevented to hire laborers effectively. In the linkages of spatial and raw material, most factories in the complex depended on the availability of out side the Kumi city. For the textile factories, the supply of raw material and parts were relied on Taegu and/or other cities, whereas in electronic factories purchased them mainly from other cities and partly from abroad. Although questionnaire and interview suggested it, most of the parts were supplied by a parts maturing companies on the complex to a few large enterprises. In the marketing linkage, textile factories revealed higher relation-ship with the foreign countries and sewing factories in Korea. On the other hand, electronic factories have strong relation-ships in the marketing linkage to the parts supplying companies in the complex or large-scale resembling companies in other cities. In the textile companies, the right for decision on purchasing raw materials and parts is belonging to the owner whereas mother enterprise usually have the right for the marketing. In the case of the electronic factories, all the purchasing activities are related to the sub-contracting companies. In the service linkage, the Quality of the service created spatial distinction. There was high linkages on inside of Kumi complex for the low grade services such as repairing and installing machines, whereas strong linkages on outside of the complex for the high grade services such as management, law, taxation, new product development. and manufacturing technology. In the linkages of activity on the R&D (research and development), electronic factories do not have sufficiently qualified institutes in the complex. Strong regional linkages in the field of textile and electronic industries revealed limitations of the local industrial complex. In the sub-contracting linkage, high linkage ship within Kumi boundary reflected the characteristics of industrial site in the complex. There, most decisions by the companies centered by the mother enterprise.