• 제목/요약/키워드: Population parameters

검색결과 856건 처리시간 0.03초

Pig Spermatozoa Defect in Acrosome Formation Caused Poor Motion Parameters and Fertilization Failure through Artificial Insemination and In vitro Fertilization

  • Lee, Won Young;Lee, Ran;Kim, Hee Chan;Lee, Kyung Hoon;Cui, Xiang Shun;Kim, Nam Hyung;Kim, Sang Hyun;Lee, Il Joo;Uhm, Sang Jun;Yoon, Min Jung;Song, Hyuk
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제27권10호
    • /
    • pp.1417-1425
    • /
    • 2014
  • The selection of morphologically normal spermatozoa is critical to obtain high breeding performances in boar breeding farms and artificial insemination (AI) centers. Parameters for the selection of semen mainly include total sperm motility, concentration, and morphology. However, these primary parameters are often not reliable for discriminating between normal and abnormal, non-fertilizable spermatozoa. The present study was designed to compare the motion characteristics, fertilization ability using in vitro fertilization (IVF), and acrosome formation of the semen from boars having low (boar number 2012) and normal (boar number 2004 and 2023) breeding performances. The ultimate goal was to identify additional simple and easy criteria for the selection of normal sperm. There was no significant difference between boar 2004 and boar 2023 sperm total motility in computer assisted sperm analysis. However, boar number 2012 semen presented a significantly reduced population of rapid moving spermatozoa and an increased population of slow moving spermatozoa compared to boar numbers 2004 and 2023. Analysis of detailed motion characteristics revealed that sperm from boar number 2012 had significantly reduced motility in progressiveness, average path velocity, straight-line velocity (VSL), curvilinear velocity (VCL), straightness, and linearity. The assessment of the fertilizing ability by IVF also showed that sperm from boar number 2012 showed a fertility rate of 3.4%, whereas sperm from boar number 2023 had a fertility rate of 75.45%. Interestingly, most of the sperm nuclei were found on the peripheral area of the oocytes, suggesting that the sperm from boar number 2012 lacked penetration ability into the oocyte zonapellucida. The acrosome formation analysis using Pisum sativum agglutinin staining demonstrated that the sperm from boar number 2012 had a defect in acrosome formation. Consequently, primary parameters for selecting semen before AI such as motility are not sufficient to select normal and fertilizable spermatozoa. In conclusion, the present study suggests that the acrosome staining and detailed motion characteristics such as progressiveness, VCL, and VSL should be included in determining semen quality together with primary parameters for successful AI and high breeding performance in the swine industry.

공간층화표본설계에 대한 보정 (Calibration for Spatial Stratified Sampling Design)

  • 변종석;손창균;김종민
    • Communications for Statistical Applications and Methods
    • /
    • 제17권1호
    • /
    • pp.9-16
    • /
    • 2010
  • 일반적으로 공간모집단에서의 표본설계에 대한 연구는 가정된 종속관계에 대해 설정된 모형 하에서 이루어지며, 이때 추정하고자 하는 모수들은 평균, 비율 그리고 면적 등이 될 수 있다. 본 연구에서는 연구대상이 지리적 조건이나, 모양에 의해 층화된 모집단에 대해 영역을 추정하고자 할 때, 공간적으로 관련이 있는 보조변수를 활용하여 가중치 조정방법을 제시하고, 이에 대한 효율성을 검증하고자 한다. 즉, 공간 추정량에 대한 보정추정과정을 적용하여 가중치 조정을 통한 추정량을 개선하고, 수치적 예제를 통해 제안된 추정량이 효율적임을 제시하였다.

바이러스-진화 유전 알고리즘을 이용한 퍼지 모델링 (Fuzzy Modeling Using Virus-Evolutionary Genetic Algorithm)

  • 이승준;주영훈;박진배
    • 한국지능시스템학회논문지
    • /
    • 제10권5호
    • /
    • pp.432-441
    • /
    • 2000
  • 본 논문은 기존의 수학적인 모델링으로는 만족스러운 결과를 얻기 어려운 복잡하고 불확실한 비선형 시스템에 대한 퍼지 모델링 기법을 다룬다. 유전 알고리듬은 어느 정도 최적해를 전역적으로 찾을 수 있기 때문에 퍼지 모델링시에 파라미커와 구조를 동정하기 위하여 사용되었다. 하지만, 유전 알고리듬은 개체군이 유전적 다양성을 잃었을 경우 조기 수렴한다는 문제점이 있으며 바이러스-진화 유전 알고리듬은 이러한 지역수렴에 대한 방아닝 될 수 있다. 따라서, 본 논문에서는 바이러스 이론이 적용된 VEGA를 퍼지 모델링 할 때 이용할 수 있는 방법을 제안한다. 이 방법에서는 지역정보가 개체군 내에서 교환됨으로써 유전적 다양성을 유지하게 된다. 마지막으로, 본 논문에서 제안한 방법의 우수성과 일반성을 평가하기 위해 몇 가지의 수치적 예제를 제공한다.

  • PDF

Population Structure of Codium amplivesiculatum (Chlorophyta) Associated with Rhodolith Beds from the Southwestern Gulf of California

  • Riosmena-Rodriguez, Rafael;Holguin-Acosta, Elena
    • ALGAE
    • /
    • 제23권2호
    • /
    • pp.141-150
    • /
    • 2008
  • Populations of Codium amplivesiculatum were found in association with rhodolith beds. We present population trends of C. amplivesiculatum from surveys conducted in the southwestern Gulf of California based on monthly sampling from June 1999 to August 2000. Surveys were conducted at 2 sites in the San Lorenzo Channel at depths of 8 - 12 m. The parameters measured were percent cover, biomass and structure in relation to size of the thalli. From each thallus the following measurements were taken: length and diameter, proportion of each thallus with reproductive structures and the degree of fragmentation (measured as number of small thalli). Mean biomass and cover varied seasonally with the maximum (1036.6 gm$^{-2}$ and 100% cover) present in June 2000 and the minimum in winter (0 gm$^{-2}$ and 0% cover). The longest fronds (3 m) occurred during July 1999 and August 2000, while the maximum diameters of 1.0 cm were present during October and November 1999. There were no significant linear relationships between length and diameter of the fronds, suggesting independent growth. Reproductive structures were common in June and July 1999 with monoic and dioic thalli present. Most fronds were monoic, and this is the first record of this feature for this species. Fragmentation occurred in September, and may be associated with stress from early gametangial reproduction and the combination of high temperatures and low nutrients. A hypothetical life cycle for the species is presented.

신종 인플루엔자 대유행의 확산과 영향 모델링 (Modelling the Impact of Pandemic Influenza)

  • 천병철
    • Journal of Preventive Medicine and Public Health
    • /
    • 제38권4호
    • /
    • pp.379-385
    • /
    • 2005
  • The impact of the next influenza pandemic is difficult to predict. It is dependent on how virulent the virus is, how rapidly it spreads from population to population, and the effectiveness of prevention and response efforts. Despite the uncertainty about the magnitude of the next pandemic, estimates of the health and economic impact remain important to aid public health policy decisions and guide pandemic planning for health and emergency sectors. Planning ahead in preparation for an influenza pandemic, with its potentially very high morbidity and mortality rates, is essential for hospital administrators and public health officials. The estimat ion of pandemic impact is based on the previous pandemics- we had experienced at least 3 pandemics in 20th century. But the epidemiologi cal characteristics - ie, start season, the impact of 1st wave, pathogenicity and virulence of the viruses and the primary victims of population were quite different from one another. I reviewed methodology for estimation and modelling of pandemic impact and described some nations's results using them in their national preparedness plans. And then I showed the estimates of pandemic influenza impact in Korea with FluSurge and FluAid. And, I described the results of pandemic modelling with parameters of 1918 pandemic for the shake of education and training of the first-line responder health officials to the epidemics. In preparing influenza pandemics, the simulation and modelling are the keys to reduce the uncertainty of the future and to make proper policies to manage and control the pandemics.

Mobile User Interface Pattern Clustering Using Improved Semi-Supervised Kernel Fuzzy Clustering Method

  • Jia, Wei;Hua, Qingyi;Zhang, Minjun;Chen, Rui;Ji, Xiang;Wang, Bo
    • Journal of Information Processing Systems
    • /
    • 제15권4호
    • /
    • pp.986-1016
    • /
    • 2019
  • Mobile user interface pattern (MUIP) is a kind of structured representation of interaction design knowledge. Several studies have suggested that MUIPs are a proven solution for recurring mobile interface design problems. To facilitate MUIP selection, an effective clustering method is required to discover hidden knowledge of pattern data set. In this paper, we employ the semi-supervised kernel fuzzy c-means clustering (SSKFCM) method to cluster MUIP data. In order to improve the performance of clustering, clustering parameters are optimized by utilizing the global optimization capability of particle swarm optimization (PSO) algorithm. Since the PSO algorithm is easily trapped in local optima, a novel PSO algorithm is presented in this paper. It combines an improved intuitionistic fuzzy entropy measure and a new population search strategy to enhance the population search capability and accelerate the convergence speed. Experimental results show the effectiveness and superiority of the proposed clustering method.

Smart-City Development Management: Goals and Instruments

  • KALENYUK, Iryna;TSYMBAL, Liudmyla;UNINETS, Iryna
    • International Journal of Computer Science & Network Security
    • /
    • 제22권1호
    • /
    • pp.324-330
    • /
    • 2022
  • At the present stage of the world economic development, a new economic system is being formed, in which non-economic values, in particular environmental and social parameters, have become widespread. A new vision of economic activity is being formed, which acquires the qualities of Smart-economy. The purpose of this paper is reveal the features of managing the development of smart cities as specific entities of the Smart-economy. New functions of economic entities are formed within the framework of the Smart-economy concept, while their role and weight in the localities' activity or formation have changed. Determining that the key trends in the Smart-economy development are such as digitalization, greening, socialization, institutionalization, and urbanization, this is necessary to note that all these trends are most active in the formation of urban ecosystems. These trends are determined by the general population growth and the urban population growth, which requires considerable attention to planning each city's development itself. Such planning could ensure the comfort of living for all its inhabitants, quality, safe, and modern life. The Smart-city's key elements and the intellectualized approach implementation planes to the decision of these or those tasks are definedIt is determined that a new ecosystem of governance is being formed.

수문 및 지형특성과 인구분포를 고려한 지반침하 발생 평가인자 분석 (Analysis of Land Subsidence Risk Factors Considering Hydrological Properties, Geomorphological Parameters, and Population Distribution)

  • 이예영;이다해;배은지;이충모;최한나
    • 한국지하수토양환경학회지:지하수토양환경
    • /
    • 제28권6호
    • /
    • pp.45-57
    • /
    • 2023
  • To assess land subsidence estimation and preparedness in the Geum River basin, this study applied GIS techniques and identified six key areas. The Geum River basin has experienced an increase in heavy rainfall since late 2010, and four study areas have shown an increase in groundwater levels. Land subsidence primarily occurred from June to September, with higher rainfall years in 2020 and 2023. Approximately 83.6% of land subsidence in Chungcheongbuk-do province occurred in Cheongju-si, mainly attributed to aging sewage pipes. The regions experiencing population growth have likely led to the construction of underground infrastructures and sewer pipes. Thus, it is considered that various factors, including sewage pipe leaks, precipitation, slope gradient, low drainage density, and groundwater level fluctuations, have contributed to land subsidence. Improving land subsidence estimation involves incorporating additional natural factors and human activities.

Parametric study of population balance model on the DEBORA flow boiling experiment

  • Aljosa Gajsek;Matej Tekavcic;Bostjan Koncar
    • Nuclear Engineering and Technology
    • /
    • 제56권2호
    • /
    • pp.624-635
    • /
    • 2024
  • In two-fluid simulations of flow boiling, the modeling of the mean bubble diameter is a key parameter in the closure relations governing the intefacial transfer of mass, momentum, and energy. Monodispersed approach proved to be insufficient to describe the significant variation in bubble size during flow boiling in a heated pipe. A population balance model (PBM) has been employed to address these shortcomings. During nucleate boiling, vapor bubbles of a certain size are formed on the heated wall, detach and migrate into the bulk flow. These bubbles then grow, shrink or disintegrate by evaporation, condensation, breakage and aggregation. In this study, a parametric analysis of the PBM aggregation and breakage models has been performed to investigate their effect on the radial distribution of the mean bubble diameter and vapor volume fraction. The simulation results are compared with the DEBORA experiments (Garnier et al., 2001). In addition, the influence of PBM parameters on the local distribution of individual bubble size groups was also studied. The results have shown that the modeling of aggregation process has the largest influence on the results and is mainly dictated by the collisions due to flow turbulence.

제2종(第2種) 중단(中斷) 자료(資料)에서 두 모수지수분포(母數指數分布)의 베이지안 추정(推定) (Bayesian Estimations for the Two-parameter Exponential Model under the Type-II Censoring)

  • 김헌주;윤용화;고정환
    • Journal of the Korean Data and Information Science Society
    • /
    • 제4권
    • /
    • pp.65-74
    • /
    • 1993
  • Suppose that we have two populations(or systems), say ${\Pi}_{1}\;and\;{\Pi}_{2}$, to be tested. A random sample of size n from each population is taken and the test for each system will be terminated when the first r failures among n random samples are observed. This kind of test is caned the type-II censored (or item-censored) testing without replacement. Under this scheme we consider the problem of estimating the unknown parameters of interests and the reliability for a given time t for each population.

  • PDF