• 농업과학연구
• /
• 제50권2호
• /
• pp.207-218
• /
• 2023

Duck farming restriction refers to a program in which duck farms suspend their operations for a certain period at times when the risk of avian influenza (AI) is high and receive compensation from the Korean government. This study analyzed the effect of this duck farming restriction on the incidence of AI using data on regional AI incidence rates, the program participation rate, and characteristics of poultry farming in 2016 (before the implementation of the restriction), as well as data from 2020 and 2021 (when new AI outbreaks occurred). In this study, the treatment group was divided into five subgroups according to the policy participation rate and a difference-in-difference (DID) estimation was conducted using certain covariates, in this case the average number of ducks raised, the land area, the number of high-susceptibility farms, the number of low-susceptibility farms, the average number of farms within a 3 km radius, the average distance to the nearest farm, and a year dummy. The results showed that when more than 30% of all duck farms in a region participated in the farming restriction, it had a statistically significant effect on the incidence of AI. Specifically, when more than 30, 40, 50, and 60% of all duck farms participated in the farming restriction, the AI incidence rate decreased by 0.7184, 1.0025, 1.5844, and 1.5843%p, respectively.

• Journal of information and communication convergence engineering
• /
• 제7권4호
• /
• pp.496-500
• /
• 2009

In EBCOT, the context modeling process takes excessive calculation time and this paper proposed a method to reduce this calculation time. That is, if the finest resolution coefficient is less than a pre-defined transfer factor the coefficient and its descendents skip the context modeling process. There is a trade-off relationship between the calculation time and the image quality or the amount of output data such that as this threshold value increases, the calculation time and the amount of output data decreases, but the image degradation increases. The experimental results showed that in this range the resulting reduction rate in calculation time was from 3% to 64% in average, the reduction rate in output data was from 32% to 73% in average.

• 전자공학회논문지B
• /
• 제30B권3호
• /
• pp.50-59
• /
• 1993

There is basic problem with the current evaluation method for character recognition systems. The current method evaluates the average recognition rate by applying the test data to the target system. The average recognition rate tells no more than and no less than the overall performance and it depends on the data. In this paper we propose a testing method which will analyze the target system and point out its strong points and weak points. This can be made possible through using the data which are generated cy distorting the standard character images according to a carefully controlled manner. This paper will describe how to automatically generate such distorted images. Also we will show the method is actually effective and useful by applying it to evaluating existing recognition algorithms.

• Journal of electromagnetic engineering and science
• /
• 제13권3호
• /
• pp.151-157
• /
• 2013

Marine radars are affected by sea and rain clutters, which can make target discrimination difficult. The clutter standard deviation and improvement factor are applied using multiple parameters-moving speed of radar, antenna speed, angle, etc. When a radar signal is processed, a Data Matrix Bank (DMB) filter can be applied to remove sea clutters. This filter allows detection of a target, and since it is not affected by changes in adjacent clutters resulting from a multi- target signal, sea state clutters can be removed. In this paper, we study the level for clutter removal and the method for target detection. In addition, we design a signal processing algorithm for marine radars, analyze the performance of the DMB filter algorithm, and provide a DMB filter algorithm design. We also perform a DMB filter algorithm analysis and simulation, and then apply this to the DMB filter and cell-average constant false alarm rate design to show comparative results.

• 대한안전경영과학회:학술대회논문집
• /
• 대한안전경영과학회 2002년도 춘계학술대회
• /
• pp.121-127
• /
• 2002

In this paper, we propose traffic management support and evaluate the performance through simulation. We suggest traffic management routing protocol that can guarantee reliance according to not only reduction of the Network traffic congestion but also distribution of the network load that prevents data transmission. For performance evaluation, we analyzed the average data reception rate and network load, considering the node mobility. We found that in the mobile Ad Hoc networks, the traffic management service increased the average data reception rate and reduced the network traffic congestion and network load in Mobile Ad Hoc Networks.

• 한국수자원학회논문집
• /
• 제51권10호
• /
• pp.839-852
• /
• 2018

본 연구의 목적은 기상자료(강수량, 최고기온, 최저기온, 평균기온, 평균풍속) 기반의 다중선형 회귀모형을 개발하여 농업용저수지 저수율을 예측하는 것이다. 나이브 베이즈 분류를 활용하여 전국 1,559개의 저수지를 지리형태학적 제원(유효저수량, 수혜면적, 유역면적, 위도, 경도 및 한발빈도)을 기준으로 30개 군집으로 분류하였다. 각 군집별로, 기상청 기상자료와 한국농어촌공사 저수지 저수율의 13년(2002~2014) 자료를 활용하여 월별 회귀모형을 유도하였다. 저수율의 회귀모형은 결정계수($R^2$)가 0.76, Nash-Sutcliffe efficiency (NSE)가 0.73, 평균제곱근오차가 8.33%로 나타났다. 회귀모형은 2년(2015~2016) 기간의 기상청 3개월 기상전망자료인 GloSea5 (GS5)를 사용하여 평가되었다. 현재저수율과 평년저수율에 의해 산정되는 저수지 가뭄지수(Reservoir Drought Index, RDI)에 의한 ROC (Receiver Operating Characteristics) 분석의 적중률은 관측값을 이용한 회귀식에서 0.80과 GS5를 이용한 회귀식에서 0.73으로 나타났다. 본 연구의 결과를 이용해 미래 저수율을 전망하여 안정적인 미래 농업용수 공급에 대한 의사결정 자료로 사용할 수 있을 것이다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제17권9호
• /
• pp.1214-1218
• /
• 2004

Data on 958 Karan Fries (KF) and 780 Karan Swiss (KS) cows, born during 1974 to 1992 at National Dairy Research Institute, Karnal were evaluated for causes of culling and their impact on milk performance and herd strength. Causes of culling were classified as voluntary culling (low milk yield) and involuntary culling (other than milk yield). The milk yield of cows was evaluated inretrospectively by estimating expected breeding value (EBV) on the basis of first lactation yield (FLY) and all available lactation yield (ALY). The culling rate of KF cows over the years varied from 10.89 (1988) to 33.92% (1991) with an overall average of 20.96% and in KS from 19.91 (1984) to 33.74% (1989) with an overall average of 25.01%. Reproductive disorders, teat and udder problems, low milk production, health and locomotive disorders were the major reasons of culling accounted respectively for 5.56, 4.97, 4.61, 3.18 and 2.24% of herd strength in KF cows. The corresponding causes of culling were 6.20, 6.26, 7.69, 1.49 and 2.67% of herd strength in KS cows. The involuntary culling of cows accounted for 82.4% in K F and 76.1% in KS cows of total culling. The average annual disposal rate in KF and KS was 26 and 30% whereas annual replacement rate was 24 and 26% respectively. The EBV of involuntary culled cows on the basis of FLY and ALY was 3,111 and 3,515 kg in KF; and 2,669 and 2,940 kg in KS cows respectively. The EBV of selected cows on the basis of FLY and ALY was 3,242 and 3,549 kg in KF and 2,893 and 3,245 kg in KS cows respectively. The average breeding value of involuntary culled cows was not significantly different from selected cows in both the herds. The high rate of involuntary culling of potential cows might be major factor responsible for declined performance and size in these herds. The results indicated that higher genetic gain (2.14% of herd average in KF and 3.49% of herd average in KS) could be obtained by restricting the involuntary culling (50% of total culling) through improved management practices and increasing replacement rate.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2003년도 추계학술대회 논문집 전력기술부문
• /
• pp.272-274
• /
• 2003

Distribution system reliability evaluation estimates by approach methods such as Makove modelling or Monte Carlo simulation, equation of state and failure rate that is on one basic data used to these assessment technique is described as probability of average value. because average failure rate equipment device is aged as time goes by but there is shortcoming that such used failure rate does not evaluate thing which is correct in reliability change hereafter. In this paper, failure rate displayed that apply aging to basis equipment device by passing time using Weibull distribution one of life evaluation method and for express aging of component from utility's failure database.

• 한국산업정보학회논문지
• /
• 제10권1호
• /
• pp.1-8
• /
• 2005

다중 반송파 기술과 CDMA 기술이 결합된 MC-CDMA 시스템은 주파수 선택적 페이딩에 의한 신호감쇄를 완화시키면서 높은 전송률에 대한 요구를 만족시킬 수 있는 전송방식이다. 본 논문에서는 전송률이 서로 다른 다양한 서비스들을 지원하기 위한 새로운 비동기 MC-CDMA 시스템을 제안한다. 제안된 시스템에서는 전송속도에 따라 병렬 부 채널의 수(P)를 조절함으로서 다중전송률 시스템을 구성하며, 이런 시스템 성능을 수식적으로 분석한다 시스템 성능은 평균 비트 오류율로 나타내었다. 여기서 평균 비트 오류율은 무선 채널을 통과한 수신신호의 간섭전력을 수치적으로 구한 후, 가우시안 근사방법을 이용하여 얻는다. 제안된 시스템과 단일 데이터율을 갖는 MC-CDMA시스템의 성능과 비교한다.

• Journal of information and communication convergence engineering
• /
• 제14권3호
• /
• pp.153-162
• /
• 2016

Microwave and millimeter waves are considered suitable frequency ranges for diverse applications. The prediction of rain attenuation required the 1-min rainfall rate distribution, particularly for data obtained locally from experimental measurement campaigns over a given location. Rainfall rate data acquired from Korea Meteorological Administration (KMA) for nine major sites are analyzed to investigate the statistical stability of the cumulative distribution of rainfall rate, as obtained from a 10-year measurement. In this study, we use the following rain rate conversion techniques: Segal, Burgueno et al., Chebil and Rahman, exponential, and proposed global coefficient methods. The performance of the proposed technique is tested against that of the existing rain rate conversion techniques. The nine sites considered for the average 1-min rain rate derivation are Gwangju, Daegu, Daejeon, Busan, Seogwipo, Seoul, Ulsan, Incheon, and Chuncheon. In this paper, we propose a conversion technique for a suitable estimation of the 1-min rainfall rate distribution.