• Title/Summary/Keyword: technology outflow

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Analysis of Risk Factors for Youth Population Outflow in Busan Based on Machine Learning (머신러닝 기반 부산 청년인구 유출위험 요인 분석)

  • Seoyoung Sohn;Hyeseong Yang;Minseo Park
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.6
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    • pp.131-136
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    • 2023
  • Local youth outmigration is increasingly growing. Various studies are being conducted to identify the factors contributing to this problem, but there is a lack of research analyzing each region individually. Therefore, this study aims to analyze the factors influencing youth outmigration in Busan and predict the risk levels of youth population outflow using machine learning techniques. By utilizing district-level data collected from the KOSIS, we divided the population into three groups based on age (the early 20s, late 20s, and early 30s) and employed Decision Tree and Random Forest algorithms to classify and predict the risk levels of youth population outmigration. The results indicate that the predictive model for youth outmigration risk levels achieves the highest accuracies of 0.93, 0.75, and 0.63 for each age group, respectively.

The Trend of suppression technology of harmonics for distribution system (고조파 유출 억제기술의 동향)

  • Koh Hee Seog;Lee Hyun Moo;Lee Chung Sik
    • Proceedings of the KIEE Conference
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    • summer
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    • pp.330-332
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    • 2004
  • Reliance on electric power has increased together with customer's demand for delightful and convenient linging. Recently, as appeared in the rapid growth of the technology of power electronics, the installation and apparatus using semiconductor applicotion is widly supplied and used from a household goods to industrial goods. However, these machine generate harmonics current and voltage for electric power system. The harmonics current is increased voltage distortion and generate a lot of interference in the electric power system. In this paper, the trend of the trend of suppression technology of harmonics outflow and the fundamental theory about the suppression of harmonics current in the distribution system are investigated and evaluated Therefore we look forward to supply electric power of good quality to satisfy the harmonics current guide line which is applied to household goods in the world.

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Outflow Characteristics of Floating Material by Rainfall Intensity in the Upper Stream of Soyang River (소양호(昭陽湖) 상류유역(上流流域)의 강우강도(降雨强度)에 따른 부유물질유출특성(浮游物質流出特性))

  • Choi, Han-kuy;Yoo, Sang-Mo;Baek, Hyo-Sun
    • Journal of Industrial Technology
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    • v.25 no.B
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    • pp.11-18
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    • 2005
  • When it is raining or snowing, floating debris flows into a lake and raises its turbidity. High level of turbidity in the lake often causes eutrophication, which pollutes the water. In order to collect and present some essential information for effective management plan for water quality, we carried out our research at the watershed of Mandae-cheon located at the upstream of Soyang Lake. We examined water quality at the time of rainfall or snowfall to analyze the changes in the amount of suspend soils(SS) in the lake.

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Study of Formation and Development of Oxygen Deficient Water Mass, Using Ecosystem Model in Jinhae, Masan Bay (생태계 모델을 이용한 진해·마산만에서의 빈산소수괴의 형성 및 발달에 관한 연구)

  • Kim, Yeon-Joong;Kim, Myoung-Kyu;Yoon, Jung-Sung
    • Journal of Ocean Engineering and Technology
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    • v.24 no.6
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    • pp.41-50
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    • 2010
  • This study established a 3D ecosystem model composed of stratification considering the topographic heat accumulation effect and river outflow, and then applied this model to Jinhae, Masan Bay. Specifically, it reenacted the formation and developmental process of ODW according to the stratification by calculating the kinematic eddy viscosity and eddy diffusion coefficient of the stratification model. The results were used as input data for the ecosystem model and compared with DO, COD, I-N, and I-P, which is the standard index of ocean water quality. As a result, it was determined that COD and T-N are third grade and T-P is second grade standards for a natural environment.

A Numerical Study on Combined Solution and Evaporation during Spin Coating Process (Wafer Spin Coating 공정에서 증발과 용액이 박막 형성에 미치는 영향에 관한 연구)

  • 노영미;임익태;김광선
    • Journal of the Semiconductor & Display Technology
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    • v.2 no.1
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    • pp.25-29
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    • 2003
  • The fluid flow, mass transfer, heat transfer and film thickness variation during the spin coating process are numerically studied. The model is said to be I-dimensional because radial variations in film thickness, concentration and temperature are ignored. The finite difference method is employed to solve the equations that are simplified using the similarity transformation. In early time, the film thinning is due to the radial convective outflow. However that slows during the first seconds of spinning so the film thinning due to evaporation of solvent becomes sole. The time varing film thickness is analyzed according to the wafer spin speed, the various solvent fraction in the coating liquid, and the various solvent vapor fraction in the bulk of the overlying gas during the spin coating is estimated.

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Evaluation of Overtopping Risks of Levee by using Reliability Analysis (신뢰성 해석에 의한 제방의 월류 위험도 산정)

  • Lee, Cheol-Eung;Park, Dong-Heon;Shim, Jae-Wook
    • Journal of Industrial Technology
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    • v.29 no.A
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    • pp.101-110
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    • 2009
  • Due to frequent occurrence of a localized torrential downpour caused by global warming and change of outflow tendency caused by rapid urbanization and industrialization, risk analysis must be carried out in levee design with uncertainty. In this study, reliability analysis was introduced to quantitatively evaluate the overtopping risk of levee by the uncertainty. First of all, breaking function was established as a function of flood stage and height of levee. All variables of breaking function were considered as random variables following any distribution functions, and the risk was defined as the possibility that the flood stage is formed higher than height of levee. The risk evaluation model was developed with AFDA (Approximate Full Distribution Approach). The flood stage computed by 2-D numerical model FESWMS-2DH was used as input data for the model of levee risk evaluation. Risk for levee submergence were quantitatively presented for levee of Wol-Song-Cheon.

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증발을 고려한 Wafer Spin Coating 박막 예측에 관한 수치 해석적 연구

  • 노영미;임익태;김광선
    • Proceedings of the Korean Society Of Semiconductor Equipment Technology
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    • 2002.11a
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    • pp.20-26
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    • 2002
  • The fluid flow, mass transfer, heat transfer and film thickness variation during the spin coating process are numerically studied. The model is said to be 1-dimensional because radial variations in film thickness, concentration and temperature are ignored. The finite difference method is employed to solve the equations that are simplified using the similarity transformation. In early time film thinning is due to the radial convective outflow. However that slows during the first seconds of spinning so the film thinning due to evaporation of solvent becomes sole. The time various film thickness is analyzed according to the var ious solvent fraction in the coating liquid and in the bulk of the overlying gas and the temperature variation in the liquid film during the spin coating is estimated.

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Control strategy of primary clarifier operation in wastewater treatment plant during rainfall inflow (초기강우 유입 시 하수처리시설 일차 침전지 운전제어 전략)

  • You, Kwang Tae;Kwon, Hyuk Jae
    • Journal of Korea Water Resources Association
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    • v.52 no.11
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    • pp.947-950
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    • 2019
  • The main feature of this paper is to provide a driving control strategy to improve the primary clarifier treatment efficiency in the initial rainfall inflow. With the recent development of IoT technology and sensing technology, the basis for operation control of wastewater treatment facilities has been improved. As a result of improving the efficiency of treatment of primary clarifier using on-line measurement results, it is possible to minimize the outflow of untreated sewage and contribute to the improvement of operation efficiency of wastewater treatment plants.

Preferences for Supercomputer Resources Using the Logit Model

  • Hyungwook Shim;Jaegyoon Hahm
    • Journal of information and communication convergence engineering
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    • v.21 no.4
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    • pp.261-267
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    • 2023
  • Public research, which requires large computational resources, utilizes the supercomputers of the National Supercomputing Center in the Republic of Korea. The average utilization rate of resources over the past three years reached 80%. Therefore, to ensure the operational stability of this national infrastructure, specialized centers have been established to distribute the computational demand concentrated in the national centers. It is necessary to predict the computational demand accurately to build an appropriate resource scale. Therefore, it is important to estimate the inflow and outflow of computational demand between the national and specialized centers to size the resources required to construct specialized centers. We conducted a logit model analysis using the probabilistic utility theory to derive the preferences of individual users for future supercomputer resources. This analysis shows that the computational demand share of specialized centers is 59.5%, which exceeds the resource utilization plan of existing specialized centers.

Prediction of Mean Water Level Rise Behind Low-Crested Structures and Outflow Velocity from Openings by Using a Hybrid Method Based on Two Dimensional Model Test and Hydrodynamic Numerical Modeling (단면수리모형 및 해수유동모델링 결합기법에 의한 저마루 구조물 배후의 평균수위 상승 및 개구부 유출유속 예측)

  • Lee, Dal Soo;Lee, Ki-Jae;Yoon, Jae Seon;Oh, Sang-Ho
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.29 no.6
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    • pp.410-418
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    • 2017
  • The stability of low-crested structure (LCS) and overtopping discharge over a seawall behind the LCS are influenced by the water level behind the structure. Hence, the experimental results can be distorted unless the increase of water level is known when two-dimensional experiment is carried out. In order to estimate increase of the mean water level behind the low-crested structure, this study applied a hybrid technique that combined results of two-dimensional model test and hydrodynamic numerical modeling based on the relationship between the water level and discharge. By using this technique, the mean water level increase and flow field can be obtained almost at the same time, which resolved the above problem considerably. In addition, this method can provide an approximate information about the outflow velocity from the openings of the structure, which is helpful for selecting appropriate planar configuration of the low-crested structure.