• KNOM Review
• /
• v.23 no.2
• /
• pp.18-28
• /
• 2020

With the development of the virtual community, the benefits that IT technology provides to people in fields such as healthcare, industry, communication, and culture are increasing, and the quality of life is also improving. Accordingly, there are various malicious attacks targeting the developed network environment. Firewalls and intrusion detection systems exist to detect these attacks in advance, but there is a limit to detecting malicious attacks that are evolving day by day. In order to solve this problem, intrusion detection research using machine learning is being actively conducted, but false positives and false negatives are occurring due to imbalance of the learning dataset. In this paper, a Random Oversampling method is used to solve the unbalance problem of the UNSW-NB15 dataset used for network intrusion detection. And through experiments, we compared and analyzed the accuracy, precision, recall, F1-score, training and prediction time, and hardware resource consumption of the models. Based on this study using the Random Oversampling method, we develop a more efficient network intrusion detection model study using other methods and high-performance models that can solve the unbalanced data problem.

• The Journal of Engineering Geology
• /
• v.14 no.2
• /
• pp.189-197
• /
• 2004

For a long time, groundwater has been used for a substitution for surface water but recently many problems have risen due to shortage of water resources and decrepitude of waterwells. Pneumatic fracturing technique is likely to be an efficient way to solve the problem of tile wells, in which pressure under the ground is applied to increase the amount of ground water. When applied pressure is given artificially to unstabilize the rock stress or to remove substances between fractures the groundwater can inflow. As the air pressure applied on the base rocks is stronger, permeability is getting higher, thus producing much groundwater than ever before. The result of this study show 15% increase of pumping rate in the P-5 well. After pneumatic fracturing pumping rate changed from 26m3/day to 30m3/day, drawdown rate increase from 51.12m to 56.58m, and specific yield also increased from 0.51m3/day to 0.53m3/day.

• Journal of Environmental Policy
• /
• v.12 no.3
• /
• pp.97-122
• /
• 2013

The ARDL(Autoregressive Distributed Lag) method is employed analyzes the long-run equilibrium relationships among environmental pollution($CO_2$ emissions) per capita, income levels per capita, and energy consumption per capita. The error correction model is employed to analyze the short-term effects of income and energy consumption on $CO_2$ emissions. The Toda-Yammamoto method is employed for causal analysis among the three variables. The results show that income levels, energy consumption, and $CO_2$ emissions are cointegrated. We found the N type relationship between income and $CO_2$ emissions. Long-term elasticities of income and energy consumption with respect to $CO_2$ emission were greater than their short-term elasticities. There were a bilateral causality between energy consumption and $CO_2$ emissions. There was a unilateral causality from $CO_2$ emissions to income and from energy consumption to income not vice versa. Energy consumption can be an important variable to contribute to forecasting $CO_2$ emissions.

• Journal of Animal Environmental Science
• /
• v.18 no.1
• /
• pp.45-56
• /
• 2012

This study was conducted to give basic information of the animal manure management by manure units determination for recycling farming in Cheorwon-gun. Manure units (MU) are used in the permitting, registration, and the environmental process because they allow equal standards for all animals based on manure nutrient production. An MU is calculated by multiplying the number of animals by manure unit factor for the specific type of animal. The manure unit factor for MU determination was determined by dividing amounts of manure N produced 80 kg N/year. Conversion to manure units is a procedure used to determine nutrient pollution equivalents among the different animal types. In this study, the manure unit factor based on nitrogen in Hanwoo, dairy cow, pig were 0.36, 0.8 0.105, respectively. The analysis of manure unit per ha shows that the N loading by MU is quite different by region. The nitrogen loading of manure unit (MU) per ha of cultivated land was the highest in the Galmal-eup on province with 2.4 MU/ha, which is higher than the appropriate level. The Seo-myeon province came next with 1.92 MU/ha. To be utilized as a valid program to build the recycling farming system, diverse measures shall be mapped out to properly determine manure units, evaluate N-loading and to properly manage their nutrient balance of each region.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2012.05a
• /
• pp.445-445
• /
• 2012

농업 수자원 시스템은 유역의 유출량으로부터 용수를 생산하고 농작물 재배를 위하여 용수를 공급하는 일련의 체계로서, 여름철 집중되는 강우를 저류하여 가용 용수를 확보하고 적절한 시기에 필요한 용수량의 공급을 목적으로 한다. 농업용 저수지, 용 배수로 및 평야부 수리시설물과 같은 구성 요소들은 오랜 기간에 걸쳐서 축조되어 지속 가능하고 안정적인 농업용수 공급을 수행하고 있다. 농업 수자원 시스템을 운영하는 과정에서 물 수요량에 대한 실시간 관리가 불가능하여, 수요와 공급의 불균형으로 인한 용수 공급 효율 저하 및 수리시설물의 노후화 및 누수 등으로 인한 관리 손실량 발생과 같은 문제점이 제기되었다. 스마트 물관리는 농업 수자원 환경의 급격한 변화에 대응하기 위하여 첨단 정보통신 기술을 도입하는 차세대 물관리 시스템으로 실시간 모니터링, 수자원의 분석/모의/운영 및 정보 관리 등 전 분야에서 정보화와 지능화를 구현하기 위한 기술 총화로 정의된다. 본 연구에서는 스마트 물관리를 구현하기 위한 구체적 방안으로써, 통합적인 농업용수의 실시간 운영 및 정보 관리를 위하여 첨단 정보통신기술을 이용한 모니터링 기술, 수집된 정보 분석 및 제공을 위한 웹 기반의 정보관리 기술, 정보교환을 위한 네트워크 기술 등을 통합 운영할 수 있는 체계를 구성하였다.

• The Korean Journal of Applied Statistics
• /
• v.23 no.6
• /
• pp.1047-1056
• /
• 2010

In clinical trials, patients should be randomly allocated to treatment and control groups that consider the balance of their prognostic factors(covariates). There are many randomization methods and stratification is popular in Korea. In stratification, patients are divided into strata based on covariates and then the patients are randomly assigned to the arms of each strata. If the number of covariates increases then the number of strata increases rapidly and the results may not be reliable when the patients are inadequate in each strata. To complement this problem Pocock and Simon (1975) suggested a new randomization method that called for minimization focusing on the balance of covariates. In this study, we compare the advantages and disadvantages, the imbalance of covariates, the power of minimization, and other randomization methods by simulation.

• Korean Journal of Poultry Science
• /
• v.11 no.1
• /
• pp.1-12
• /
• 1984

Since a 13% dietary protein level is generally accepted as a standard in evaluating net protein utilization values of protein sources in chicks, limiting amino acids a 13% protein basal diet containing 15% isolated soy-protein as the only source of dietary protein, were identified. Of such amino acids as methionine, lysine, threonine and tryptophan added to the basal diet singly or as a combination, methionine appeared as the only limiting amino acid for optimum growth of the chicks. When the requirement of total sulfur-containing acids (TSAA) was estimated as the point at which the dose-response curve intersected a line representing the plateau for maximum performance, the TSAA requirements for maximum growth and feed intake were 4.73% and 3.73% of dietary protein, respectively. The values, expressed in terms of TSAA intake, required for maximum weight gain, feed intake and gain/feed ratio were 167.1, 136.8 and 159.1 mg/bird/day, respectively.

• Environmental and Resource Economics Review
• /
• v.28 no.1
• /
• pp.1-37
• /
• 2019

This study investigates the convergence in per capita $CO_2$ emission by income group for an unbalanced panel of 152 countries from 1980 to 2013 using beta and sigma convergence model. Absolute beta and sigma convergence differed by $CO_2$ emission reduction policies in each countries. Conditional beta convergence shows that per capita income has a negative effect on growth in per capita $CO_2$ emission. In particular, better-quality institutions and technology accelerated the negative effect of per capita income on the speed of convergence of per capita $CO_2$ emission in high-income countries. For middle-income countries, the growth of income affected the convergence of $CO_2$ emission per capita, but institutional quality has an insignificant impact. On the other hand, improvements in the level of technology have a mitigating effect on the negative impact of income in middle-income and low-income countries, contributing to the increase in $CO_2$ emission.

• Journal of Broadcast Engineering
• /
• v.17 no.3
• /
• pp.503-518
• /
• 2012

In this paper, we propose a complexity-based parallelization method of the sample adaptive offset (SAO) algorithm which is one of HEVC in-loop filters. The SAO algorithm can be regarded as region-based process and the regions are obtained and represented with a quad-tree scheme. A offset to minimize a reconstruction error is sent for each partitioned region. The SAO of the HEVC can be parallelized in data-level. However, because the sizes and complexities of the SAO regions are not regular, workload imbalance occurs with multi-core platform. In this paper, we propose a LCU-based SAO algorithm and a complexity prediction algorithm for each LCU. With the proposed complexity-based LCU processing, we found that the proposed algorithm is faster than the sequential implementation by a factor of 2.38 times. In addition, the proposed algorithm is faster than regular parallel implementation SAO by 21%.

• Journal of Korea Water Resources Association
• /
• v.31 no.4
• /
• pp.385-396
• /
• 1998

The south-western part of Korea is situated in an unbalance of water supply and demand relating to the Keum, Mankyung, Dongjin and Youngsan River and their estuary reservoirs. For example, the Keum River estuary reservoir is discharging the larger amount of yearly runoff into the sea due to the small storage capacity, while Saemankeum estuary reservoir which is under construction, has the smaller runoff comparing with its strorage capacity. And the downstream area of the Youngsan River, such as Youngkwang, Youngam are deficient in water due to larger demand and smaller supply. In order to solve the above unbalanced water supply and demand and also to improve the water use effciency, the Hierarchical Operation Model for Multi-reservoir System(HOMMS) has been developed and applied to analyze the multi-reservoir operation assuming that the above reservoirs were linked each other. The result of this study shows that $2,148{\times}106\;\textrm{m}^3$ of annual additional water requirement for agricultural and rural water demands are required in this region at 2011 of target year, and these demands can be resolved by diverting and reusing $1,913{\times}106\;\textrm{m}^3$ of the released water from the estuary reservoirs into the sea.