• 대한임베디드공학회논문지
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• 제19권4호
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• pp.175-184
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• 2024

This research addresses the problem of robot localization in corridor environments using LiDAR (Light Detection and Ranging). Due to the rank deficiency problem in scan matching with LiDAR alone, the accuracy of robot localization may degenerate seriously. This paper proposes an adaptive sampling-based particle filtering method using depth sensors to overcome the rank deficiency problem. The increase in the sample size in particle filters can be considered to solve the problem. But, it may cause much computation cost. In the proposed method, the sample size of the particle set in the proposed method is adjusted adaptively to the confidence of depth sensor data. The performance of the proposed method was test by real experiments in various environments. The experimental results showed that the proposed method was capable of reducing the estimation errors and more accurate than the conventional method.

• Journal of applied mathematics & informatics
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• 제29권3_4호
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• pp.949-953
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• 2011

It is interesting to know the behavior of a network from its structure. One interesting topic is to find a relation between the existence of a positive equilibrium of the reaction network and its structure. One approach to study this topic is using the concept of deficiency. Another is using some conditions on nodes, which can apply to large-size networks compared to deficiency. In this work, we show the relation between deficiency and the conditions.

• Structural Engineering and Mechanics
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• 제21권5호
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• pp.539-551
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• 2005

Finite elements based on isoparametric formulation are known to suffer spurious stiffness properties and corresponding stress oscillations, even when care is taken to ensure that completeness and continuity requirements are enforced. This occurs frequently when the physics of the problem requires multiple strain components to be defined. This kind of error, commonly known as locking, can be circumvented by using reduced integration techniques to evaluate the element stiffness matrices instead of the full integration that is mathematically prescribed. However, the reduced integration technique itself can have a further drawback - rank deficiency, which physically implies that spurious energy modes (e.g., hourglass modes) are introduced because of reduced integration. Such instability in an existing stiffness matrix is generally detected by means of an eigenvalue test. In this paper we show that a knowledge of the dimension of the solution space spanned by the column vectors of the strain-displacement matrix can be used to identify the instabilities arising in an element due to reduced/selective integration techniques a priori, without having to complete the element stiffness matrix formulation and then test for zero eigenvalues.

• Journal of applied mathematics & informatics
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• 제28권5_6호
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• pp.1545-1552
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• 2010

It is interesting to know the behavior of a network from its structure. One interesting topic is to find a relation between the existence of a positive equilibrium of the reaction network and its structure. One approach to study this topic is using the concept of deficiency. In this work, we develop an algorithm and show an elementary proof of the relation based on the algorithm and deficiency.

• 대한수학회보
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• 제57권1호
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• pp.195-206
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• 2020

The fundamental idea of this article is to present an effective way to obtain the large groups in terms of the split extension obtained by a finite cyclic group and a free abelian group rank 2. The proof of the main result on largeness property of this specific split extension groups will be given by using the connection of large groups with the groups having deficiency one presentations.

• Journal of applied mathematics & informatics
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• 제30권5_6호
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• pp.787-792
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• 2012

We present a graphical algorithm and theorems for calculating the ranks of reaction networks. The ranks are needed to study behaviors of the networks from their structures. This approach can graphically simplify complex networks for the calculation. We show an example of a large network for the practical advantage.

• Communications for Statistical Applications and Methods
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• 제2권1호
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• pp.48-54
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• 1995

A direct method for fitting analysis-of-variance models to unbalanced data is presented. This method exploits sparsity and rank deficiency of the matrix and is based on Gram-Schmidt orthogonalization of a set of sparse columns of the model matrix. The computational algorithm of the sum of squares for testing estmable hyphotheses is given.

• 한국측량학회지
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• 제25권3호
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• pp.207-213
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• 2007

다수의 고정수신기를 이용하여 이동수신기의 위치를 정확히 측정하고자 하는 필요성은 계속적으로 대두되고 있었으나, 현재 사용되고 있는 대부분의 상용 소프트웨어에서는 단일기선에 대한 GPS 결과만을 제공하고 있다. 따라서 본 논문에서는 다수의 단일기선 결과를 이용하여 네트워크를 구성함으로써 이동수신기의 위치측정 정확도를 향상시키기 위한 방안을 연구하였다. 이를 위해 기존의 측지 망 조정 이론을 도입하여 이동수신기의 위치결정 분야에 적용함으로써 위치정확도 향상 뿐만 아니라 전체적인 네트워크의 안정에도 기여할 수 있음을 알 수 있었다. 또한 측지망의 계수부족(Rank-deficiency)을 제거하기 위해서 하나의 고정수신기의 위치를 고정시키는 방법(RLESS), 이동수신기의 바이어스(Bias)를 최소화하는 방법(BLIMPBE), 그리고 고정수신기의 위치에 확률적 제약 조건을 주는 방법(SCLESS)에 대해서 비교 분석하였다. 네트워크 기반의 위치결정을 통해서 3차원 평균제곱근오차(RMSE)는 최대 3.5cm에서 2.1cm 수준으로 향상되었고, 기준점의 위치정확도에 따라 BLIMPBE 및 SCLESS 방법을 적절히 적용하는 것이 바람직할 것으로 판단된다.

• International Journal of Control, Automation, and Systems
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• 제3권3호
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• pp.430-443
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• 2005

A general construction algorithm of the Grassmann space parameters in linear systems - so-called, the Plucker matrix, 'L' in m-input, p-output, n-th order static output feedback systems and the Plucker matrix, $'L^{aug}'$ in augmented (m+d)-input, (p+d)-output, (n+d)-th order static output feedback systems - is presented for numerical checking of necessary conditions of complete static and complete minimum d-th order dynamic output feedback pole-assignments, respectively, and also for discernment of deterministic computation condition of their pole-assignable real solutions. Through the construction of L, it is shown that certain generically pole-assignable strictly proper mp > n system is actually none pole-assignable over any (real and complex) output feedbacks, by intrinsic rank deficiency of some submatrix of L. And it is also concretely illustrated that this none pole-assignable mp > n system by static output feedback can be arbitrary pole-assignable system via minimum d-th order dynamic output feedback, which is constructed by deterministic computation under full­rank of some submatrix of $L^{aug}$.

• 기본간호학회지
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• 제6권2호
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• pp.331-346
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• 1999

Many studies have reported that a lot of nursing colleges do not have good facilities for the nursing practice in hospitals, so many students do not have the good ability which is needed to be a competent nurse. The purpose of this study was to develop a program in which students could improve their ability in fundamental nursing skills before the graduation. This study was primarily designed to identify items of the fundamental nursing practice in which nursing college students have perceived deficiencies. According to previous studies, a total 75 items were presented. In Identifying them, a modified Porter format was used. The questionnaire contained three sections. A. How well do you think you can/could perform the item when you graduate/graduated the college? B. How well do you think you should perform/should be able to perform the item when you graduate/graduated the college? C. How important do you think the item is? For each of the 75 items, the respondents were instructed to answer the above three questions, by circling a number on a rating scale extending from 1 to 5, where low numbers represented a low degree of performance or minimum amount, and high numbers represented a high degree of performance or maximum amount. The perceived degree of deficiency in performance on each questionnaire item was obtained by subtracting the answer to Part A of an item from that to of Part B. The larger difference means a larger perceived degree of deficiency in performance. This method of measuring the perceived degree of deficiency in performance is an indirect measure derived from two direct answers by the respondent for each item. From this result Part C of each item was used to rank the items, and the items were prioritized. The items which had the highest priority were IV injection, simple catheterization, indwelling catheterization, CPR, and nurse recording. By this method, through these results from a nursing college, and the items which will be used first in developing the supplementation program for nursing college students can be identified.