• Title/Summary/Keyword: Mixed distribution

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Seasonal Distribution of Ticks in Four Habitats near the Demilitarized Zone, Gyeonggi-do (Province), Republic of Korea

  • Chong, Sung Tae;Kim, Heung Chul;Lee, In-Yong;Kollars, Thomas M. Jr.;Sancho, Alfredo R.;Sames, William J.;Chae, Joon-Seok;Klein, Terry A.
    • Parasites, Hosts and Diseases
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    • v.51 no.3
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    • pp.319-325
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    • 2013
  • This study describes the seasonal distribution of larvae, nymph, and adult life stages for 3 species of ixodid ticks collected by tick drag and sweep methods from various habitats in the Republic of Korea (ROK). Grasses less than 0.5 m in height, including herbaceous and crawling vegetation, and deciduous, conifer, and mixed forests with abundant leaf/needle litter were surveyed at United States (US) and ROK operated military training sites and privately owned lands near the demilitarized zone from April-October, 2004 and 2005. Haemaphysalis longicornis Neumann adults and nymphs were more frequently collected from April-August, while those of Haemaphysalis flava Neumann and Ixodes nipponensis Kitaoka and Saito were collected more frequently from April-July and again during October. H. longicornis was the most frequently collected tick in grass habitats (98.9%), while H. flava was more frequently collected in deciduous (60.2%) and conifer (57.4%) forest habitats. While more H. flava (54.1%) were collected in mixed forest habitats than H. longicornis (35.2%), the differences were not significant. I. nipponensis was more frequently collected from conifer (mean 8.8) compared to deciduous (3.2) and mixed (2.4) forests.

A Method to Improve the Performance of Adaboost Algorithm by Using Mixed Weak Classifier (혼합 약한 분류기를 이용한 AdaBoost 알고리즘의 성능 개선 방법)

  • Kim, Jeong-Hyun;Teng, Zhu;Kim, Jin-Young;Kang, Dong-Joong
    • Journal of Institute of Control, Robotics and Systems
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    • v.15 no.5
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    • pp.457-464
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    • 2009
  • The weak classifier of AdaBoost algorithm is a central classification element that uses a single criterion separating positive and negative learning candidates. Finding the best criterion to separate two feature distributions influences learning capacity of the algorithm. A common way to classify the distributions is to use the mean value of the features. However, positive and negative distributions of Haar-like feature as an image descriptor are hard to classify by a single threshold. The poor classification ability of the single threshold also increases the number of boosting operations, and finally results in a poor classifier. This paper proposes a weak classifier that uses multiple criterions by adding a probabilistic criterion of the positive candidate distribution with the conventional mean classifier: the positive distribution has low variation and the values are closer to the mean while the negative distribution has large variation and values are widely spread. The difference in the variance for the positive and negative distributions is used as an additional criterion. In the learning procedure, we use a new classifier that provides a better classifier between them by selective switching between the mean and standard deviation. We call this new type of combined classifier the "Mixed Weak Classifier". The proposed weak classifier is more robust than the mean classifier alone and decreases the number of boosting operations to be converged.

Perception on Social Mix of Managers and Residents in the Mixed Housing Complexes for Sale and Rental Apartment (분양임대혼합아파트 단지의 소셜믹스에 대한 관리자 및 거주자 의식조사)

  • Lee, Soomin;Kim, Youngjoo
    • Journal of the Korean housing association
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    • v.25 no.6
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    • pp.27-37
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    • 2014
  • The purpose of this study was to identify the perception on social mix of managers and residents in the mixed housing complexes for sale and rental apartment. For the research purpose, concept and background of social mix, relevant policies, preceding research trend of social mix were organized through the literature analysis. In addition, observation study was executed to examine physical aspects of three selected sites as research subjects. Also, current state and awareness for social mix were conducted by using in-depth interview with 6 managers and 30 residents in selected areas with semi-structured questionnaires from June 3 to 7, 2013. The results of the study are as following: In the aspect of management, managers said that the biggest issue of mix-housing complex was dualization of management subject such as delegate of residents and tenants. Therefore, legislation which is suitable for unique features of mix-housing complex is required. To decrease disharmony between condominium and rental apartment, controlling the distribution ratio between condominium and rental apartment can be a good way. Accommodating middle class in mixed-housing complex is considered to reduce the social gap. Socially, multilateral and continuous effort through government, industry and academic area is required to inspire positive awareness on social mix among residents in mixed housing complex.

Double-Diffusive Convection in a Salt-Stratified Fluid Heated From Below (농도 성층화된 유체의 아랫면 가열에 의한 이중확산대류에 관한 연구)

  • 강신형;김무현;이진호
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.18 no.12
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    • pp.3297-3304
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    • 1994
  • Experimental investigation have been made to study the double-diffusive nature of convection of an initially stratified salt-water solution heated from below in a cylindrical cavity. The objective is to examine the process of mixed-layer formation, the flow phenomena, the heat transfer characteristics, and temperature and concentration distribution according to the changes in the effective Rayleigh number based on the reference height which represents the relation of temperature and concentration gradient. The types of initially formed flow pattern are categorized in three regimes depending on the effective Rayleigh number ; stagnant flow regime, single mixed-layer flow regime and successively formed multiple mixed-layer flow regime. The temperature and concentration profiles are both uniform in each layer due to convective mixing in the layered flow regime, but both linear in stagnant flow regime and single mixed-layer flow regime. At the interface between adjacent layers, the temperature changes smoothly but the concentration changes rapidly. The layers expand by diffusion of concentration through the interface along with its random fluctuation.

Study on the Contribution of Mixing Effects in Sampling Tube and Condensation Nuclei Counter(CNC) to the measurement of size distribution obtained using Differential Mobility Analyzer and CNC (Differential Mobility Analyzer(DMA)와 Condensation Nuclei Counter(CNC)를 이용한 입자크기 분포 측정에서 샘플링 튜브와 CNC에서의 혼합 효과가 입자 크기 분포 측정에 미치는 영향에 관한 연구)

  • Lee, Youn-Soo;Ahn, Kang-Ho
    • Proceedings of the KSME Conference
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    • 2001.06d
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    • pp.104-109
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    • 2001
  • The time to measure the size distribution using Condensation Nuclei Counter(CNC) and Differential Mobility Analyzer(DMA) can be shortened by classifying particles ramping the DMA voltage exponentially and continuously. In measurement, particles sampled at different time are mixed together going through sampling tube and CNC. Because the size distribution is inversed by using detector responses to sampling time intervals in this accelerated method, the mixing effects give inversion errors to the size distribution. The mixing effects can be considered by appling the transfer function with mixing effects to the data inversion. The inversion considering this effects gives birth to the size distribution shifted to the opposite direction of the size scanning.

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Validity of Ocean Wave Spectrum Using Rayleigh Probability Density Function

  • Choi, Young Myung;Yang, Young Jun;Kwon, Sun Hong
    • International Journal of Ocean System Engineering
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    • v.2 no.4
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    • pp.250-258
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    • 2012
  • The distribution of wave heights is assumed to be a Rayleigh distribution, based on the assumption of a narrow band and Gaussian distribution of wave elevation. The present study was started with doubts about the narrow band assumption. We selected the wave spectra widely used to simulate irregular random waves. The wave spectra used in this study included the Pierson-Moskowitz spectrum, Bretschneider-Mitsuyasu spectrum, and JONSWAP spectrum. The directionality of the waves was considered. The cosine 2-l type directional spreading function and mixed form of the half-cosine 2-s type with Mitsuyasu type directional spreading are considered here to investigate the effects of a directional spreading function on random waves. The simulated wave height distribution is compared with a Rayleigh distribution.

Estimating Quantiles of Extreme Rainfall Using a Mixed Gumbel Distribution Model (혼합 검벨분포모형을 이용한 확률강우량의 산정)

  • Yoon, Phil-Yong;Kim, Tae-Woong;Yang, Jeong-Seok;Lee, Seung-Oh
    • Journal of Korea Water Resources Association
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    • v.45 no.3
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    • pp.263-274
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    • 2012
  • Recently, due to various climate variabilities, extreme rainfall events have been occurring all over the world. Extreme rainfall events in Korea mainly result from the summer typhoon storms and the localized convective storms. In order to estimate appropriate quantiles for extreme rainfall, this study considered the probability behavior of daily rainfall from the typhoons and the convective storms which compose the annual maximum rainfalls (AMRs). The conventional rainfall frequency analysis estimates rainfall quantiles based on the assumption that the AMRs are extracted from an identified single population, whereas this study employed a mixed distribution function to incorporate the different statistical characteristics of two types of rainfalls into the hydrologic frequency analysis. Selecting 15 rainfall gauge stations where contain comparatively large number of measurements of daily rainfall, for various return periods, quantiles of daily rainfalls were estimated and analyzed in this study. The results indicate that the mixed Gumbel distribution locally results in significant gains and losses in quantiles. This would provide useful information in designing flood protection systems.

Yangshao Culture and Rice Culture - In Relations to Dissemination of Rice Culture Towards to the North - East of China - (중국 앙소시대 문화와 도작농업 -재배도의 동북방향 전파노선과 관계하여-)

  • Chang, Juzhong;Wang, Xiangkun;Cui, Zong Jun;Heu, Mun Hue
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.41 no.3
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    • pp.376-383
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    • 1996
  • Distribution of archaeological sites where the rice and Itallian millets were excavated was discussed in relation to the rice culture of Yangshao era. According to the distribution of the sites where the rice and Italian millet remains were excavated, the putative border of rice growing area, Italian millet growing area and mixed-cropping area were drawn. Discussions were made about the drifting of the area of mixed-cropping, north and south, depending on the climates of archaeological eras, The climates of the eras were discussed with the various remains of animals and plants excavated from each era's sites. Examining the chronology of mixed-cropping area the extension of rice culture were traced chronologically. And the extension of rice culture towards north-east during the last period of Yangshao era, and the feasibilities of transfer to the Han-river mouth area in Korea, 5,000 aBP(about Before Present), were discussed.

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Nest Distribution of Skuas on Barton and Weaver Peninsulas of the King George Island, the Antarctic (남극 킹조지 섬의 바톤 및 위버 반도에서 번식하는 도둑갈매기류의 둥지 분포)

  • Kim, Jeong-Hoon;Chung, Ho-Sung;Kim, Ji-Hee;Yoo, Jeong-Chil;Ahn, In-Young
    • Ocean and Polar Research
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    • v.27 no.4
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    • pp.443-450
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    • 2005
  • The ratio of breeding pairs of brown skuas (Catharacta lonnbergi), south polar skuas (C. maccormicki) and mixed species pairs between Barton and Weaver peninsulas remained the same $(X^2-test,\;X^2=0,503,\;df=2,\;p=0.778)$. The nests of skuas were clustered on Barton, whereas they were distributed randomly on the Weaver peninsula. The distance between brown skua nests, and that of mixed species pair nests were longer than those of south polar skua nests. Brown skua nests were distributed along the coast. Whereas, the nests of mixed species pairs and south polar skuas were found more frequently inland (Kruskal-Wallis, $X^2=11.631$, df=2, p<0.005). There was no interspecific difference in the distances between skua nests and Penguin rookery at Barton (Kruskal-Wallis, $X^2=2.153$, df=2, p=0.341) or at King Sejong Station (ANOVA, F=1.483, df=2, p=0.229). In general, skuas prefer lower locales (<125m above sea level) for their nest building sites. Brown skua nests were distributed mainly on the beach, whereas south polar skua were distributed on the predominant periglacial landforms and till areas $(X^2-test,\;X^2=24.988,\;df=8,\;p<0.005)$.

The Cation Exchange Separation of Metal-Trien Mixed Complexes (금속-Trien 혼합착물의 양이온 교환수지상에서의 분리)

  • Yung-Kyu Park;Chul- Heui Lee;Mu-Kang Lee
    • Journal of the Korean Chemical Society
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    • v.24 no.2
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    • pp.129-138
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    • 1980
  • The formation constants of the mixed-ligand complexes in the Cd(II), Cu(II) and Pb(II)-Trien-OH system were studied by polarograph. The formation constant $(log{\beta}_{ij})$ was determined at $25^{\circ}C$ in the ionic strength of 0.1. It was also confirmed that the mixed ligand complexes in this system were formed above pH 10.2, 10.5 and 9.0 for Cu(II), Cd(II) and Pb(II) by the calculation of the distribution for complexes at the various pH. Masking of Cd(II) by conversion to anionic EDTA-complexes has been used to separate Cu(II) from Cd(II) through passage of a combined Trien-EDTA solution on an cationic resin column. The optimal condition for the separation of Cu(II) from Cd(II) is confirmed at the pH range above 9.0, not only by considering the theoretical equation of the conditional-exchange-constant of metal on the cation exchange resin,but also by calculating the distribution of the mixed ligand complexes in the resin at the various pH with computer. By analyzing the synthetic sample of Cu(II) and Cd(II) with a EDTA masking at pH 9.5, it is found that the results of the experiment are satisfied with the theoretical value.

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