Types Of Distance Measures Research Articles

Single facility location and relocation problem with time dependent weights and discrete planning horizon

In this paper a single facility location problem with multiple relocation opportunities is investigated. The weight associated with each demand point is a known function of time. We consider either rectilinear, or squared Euclidean, or Euclidean distances. Relocations can take place at pre-determined times. The objective function is to minimize the total location and relocation costs. An algorithm which finds the optimal locations, relocation times and the total cost, for all three types of distance measurements and various weight functions, is developed. Locations are found using constant weights, and relocations times are the solution to a Dynamic Programming or Binary Integer Programming (BIP) model. The time horizon can be finite or infinite.

Comparison of nematode community similarities assessed by polymerase chain reaction-denaturing gradient gel electrophoresis (DGGE) and by morphological identification

AbstractMolecular biology techniques for nematode community analysis that are high throughput and operable by non-experts are in high demand for soil biological assessments. In the development of such techniques, the closeness of the analytical results to those obtained by conventional methods is of key importance. In this context, we compared similarity relationships of nematode community structures between polymerase chain reaction-denaturing gradient gel electrophoresis (DGGE) and individual-based morphological identification (CONV) using 12 nematode samples recovered from crop field soils in four localities in Japan. First, we determined whether the primer set chosen to amplify the 18s rRNA genes of nematode taxa was suitable for DGGE by comparing community structures of four selected samples between clone libraries (CLs) and those revealed by CONV. We considered the primer set to be suitable because we found significant correlations in the structures between CLs and CONV in three of the four samples examined. Then we determined the community structure of 12 samples by both DGGE and CONV, and calculated distance matrices to examine if analytical results were similar between the two methods. The correlations in matrices were 0.400-0.603, depending on the types of distance measures, and were always significant between the two methods. In comparing dendrograms drawn based on the matrices, DGGE and CONV were actually similar to some extent in that samples from a single locality tended to group together, although some localities were split in DGGE. We also conducted DGGE with four additional selected samples to confirm that the band pattern (i.e., number, position and relative intensity) was consistent in each sample across subsamples and gels. Given these results, we expect DGGE to become a useful and efficient tool for nematode community analysis, especially for non-experts, but our method of evaluation has limitations and more tests are needed.

연결 성분 간 간격 측정에 의한 필기체 수표 금액 문장에서의 단어 추출

본 논문에서는 연결 성분간의 공간적 간격에 기반하여 수표 영상 내의 필기체 문장 금액에서 단어를 효율적으로 추출하기 위한 방법을 제안한다. 인접한 연결 성분간의 거리측정을 위한 기존의 방식들은 과대추정 또는 과소추정 문제로 인한 단어 분리 오류를 초래할 수 있으나 본 논문에서는 이러한 문제를 줄이기 위해 각 측정 방식들을 수정 보완하였다. 또한 본 논문에서는 서로 다른 형태의 세 가지 거리 측정법들을 효과적으로 결합하여 각 개별 측정법이 가지는 단점을 상호 보완하고 전체 단어 추출 성능을 좀더 향상시킬 수 있는 4-클래스 군집화에 기반한 결합 방법을 새로이 제안하였다. 분장 금액에 대한 단어 추출 실험 결과로부터 수정된 각 거리 측정법이 대응되는 기존의 측정법에 비해 2-3% 정도 향상된 단어 분리율을 보임을 확인하였다. 또한 제안된 4-클래스 군집화에 기반한 결합 방식은 각 측정 방식에서 개별적으로 발생하는 에러뿐만 아니라 두 개의 방식에서 동시에 나타나는 에러도 효율적으로 감소시킴으로서 전체 단어 분리 성능을 향상 시킬수 있었다. We have proposed an efficient method of word separation in a handwritten legal amount on bank check based on the spatial gaps between the connected components. The previous gap measures all suffer from the inherent problem of underestimation or overestimation that causes a deterioration in separation performance. In order to alleviate such burden, we have developed a modified version of each distance measure. Also, 4 class clustering based method of integrating three different types of distance measures has been proposed to compensate effectively the errors in each measure, whereby further improvement in performance of word separation is expected. Through a series of word separation experiments, we found that the modified distance measures show a better performance with over 2 - 3% of the word separation rate than their corresponding original distance measures. In addition, the proposed combining method based on 4-class clustering achieved further improvement by effectively reducing the errors common to two of three distance measures as well as the individual errors.

Genetic distance and classification of domestic animals using genetic markers

Genetic distance is used to classify and elucidate the evolutionary relationship between populations, such as species, which have been diverging for a long period. The properties of genetic distance measures in livestock classification have hitherto not been investigated. We used simulation studies to compare the accuracy of eight genetic distance measures to classify recently diverged populations. The effect of varied population sizes from generation to generation were also taken into account. Comparatively better results are obtained from Nei’s standard distance with two alleles at each locus and from Nei’s DA distance with four alleles at each locus under various conditions. However, the difference in accuracy among distance measures was small and very high correlations were shown. The number of alleles at each locus had a greater effect on accuracy than the number of loci or type of distance measures. It indicates that highly polymorphic markers, such as DNA microsatellite, are powerful tool to improve the accuracy in classification of domestic animals. The six distance measures had a linear relationship with generation number at constant population size. None of the distance measures, however, showed a linear relationship when population size varied. The effect of fluctuating population size on the average distance was obvious over the first few generations but declined when the number of generations was increased.

The Distance to the Fornax Dwarf Galaxy Using Red Clump Stars and the Discrepancy between Red Clump and Tip of the Red Giant Branch Distances

I determine a distance to the Fornax dwarf galaxy using stars in the red clump and at the tip of the red giant branch. They are in very good agreement, with μ0 = 20.66 mag. Comparing the magnitudes of the tip of the red giant branch and of the red clump in Fornax, Carina, and the Magellanic Clouds, I propose a possible solution to the problem of the discrepancy between these two types of distance measurements.

The Problem of Aggregation and Distance for Analyses of Accessibility and Access Opportunity in Location-Allocation Models

The acceptability of information stemming from analyses of accessibility and access opportunity for social, educational, and cultural infrastructure facilities largely depends on two factors: exactness and efficiency. Both of these factors are influenced by the data bases available for the analyses. This paper will focus on the problem of data requirements for spatial distributions of demand as well as on data requirements for spatial distances with respect to the exactness of the results of analyses and on the efficiency of preparing analyses. The effects of different levels of aggregation and of different types of distance measures are investigated.

Hierarchical clustering schemes.

Techniques for partitioning objects into optimally homogeneous groups on the basis of empirical measures of similarity among those objects have received increasing attention in several different fields. This paper develops a useful correspondence between any hierarchical system of such clusters, and a particular type of distance measure. The correspondence gives rise to two methods of clustering that are computationally rapid and invariant under monotonic transformations of the data. In an explicitly defined sense, one method forms clusters that are optimally “connected,” while the other forms clusters that are optimally “compact.”

Laser measurements of long distances

The extension of radio frequency techniques to the optical region of the spectrum has made possible many types of measurements which were not feasible before. One area in which important scientific contributions can be expected during the next few years is the use of lasers to measure long distances with high accuracy. Three types of distance measurements which have been discussed in the literature and which are now being investigated actively are: 1) interferometric measurements over distances of up to hundreds of meters through evacuated or sealed-off tubes, 2) measurements with modulated laser beams over distances of perhaps one to fifty kilometers with corrections made for the atmospheric index of refraction along the path, and 3) range measurements to artificial satellites and to the moon using laser radar. Some of the possible geophysical and geodetic applications of such measurements will also be discussed.