• 대한산업공학회지
• /
• 제24권1호
• /
• pp.145-156
• /
• 1998

In a classical clustering problem, grouping is done on the basis of similarities or distances (dissimilarities) among the elements. Therefore, the objective is to minimize the variance within each group while maximizing the between-group variance among all groups. In this paper, however, a new class of clustering problem is introduced. We call this a laydown grouping problem (LGP). In LGP, the objective is to minimize both the within-group and between-group variances. Furthermore, the problem is expanded to a multi-dimensional case where the two-way minimization process must be considered for each dimension simultaneously for all measurement characteristics. At first, the problem is assessed by analyzing its variance structures and their complexities by conjecturing that LGP is NP-complete. Then, the simulated annealing (SA) algorithm is applied and the results are compared against that from others.

• 대한수학회보
• /
• 제53권3호
• /
• pp.779-791
• /
• 2016

Transfer of homological properties under base change is a classical field of study. Let $R{\rightarrow}S$ be a ring homomorphism. The relations of Gorenstein projective (or Gorenstein injective) dimensions of unbounded complexes between $U{\otimes}^L_RX$(or $RHom_R(X,U)$) and X are considered, where X is an R-complex and U is an S-complex. In addition, some sufficient conditions are given under which the equalities $G-dim_S(U{\otimes}^L_RX)=G-dim_RX+pd_SU$ and $Gid_S(RHom_R(X,U))=G-dim_RX+id_SU$ hold.

• 대한수학회지
• /
• 제41권4호
• /
• pp.667-680
• /
• 2004

We generalize a theorem of W. Benz by proving the following result: Let $H_{\theta}$ be a half space of a real Hilbert space with dimension $\geq$ 3 and let Y be a real normed space which is strictly convex. If a distance $\rho$ > 0 is contractive and another distance N$\rho$ (N $\geq$ 2) is extensive by a mapping f : $H_{\theta}$ \longrightarrow Y, then the restriction f│$_{\theta}$ $H_{+}$$\rho$/2// is an isometry, where $H_{\theta}$＋$\rho$/2/ is also a half space which is a proper subset of $H_{\theta}$. Applying the above result, we also generalize a classical theorem of Beckman and Quarles.

• 응용통계연구
• /
• 제22권6호
• /
• pp.1143-1152
• /
• 2009

A canonical correlation analysis(CCA)-based method is proposed for prediction of future climate change which combines information from ensembles of atmosphere-ocean general circulation models(AOGCMs) and observed climate values. This paper focuses on predictions of future climate on a regional scale which are of potential economic values. The proposed method is obtained by coupling the classical CCA with empirical orthogonal functions(EOF) for dimension reduction. Furthermore, we generate a distribution of climate responses, so that extreme events as well as a general feature such as long tails and unimodality can be revealed through the distribution. Results from real data examples demonstrate the promising empirical properties of the proposed approaches.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• 제9권3호
• /
• pp.213-218
• /
• 2009

This paper describes a classical algorithm carrying out dynamic 3D obstacle recognition for autonomous underwater vehicles (AUVs), Support Vector Machines (SVMs). SVM is an efficient algorithm that was developed for recognizing 3D object in recent years. A recognition system is designed using Support Vector Machines for applying the capabilities on appearance-based 3D obstacle recognition. All of the test data are taken from OpenGL Simulation. The OpenGL which draws dynamic obstacles environment is used to carry out the experiment for the situation of three-dimension. In order to verify the performance of proposed SVMs, it compares with Back-Propagation algorithm through OpenGL simulation in view of the obstacle recognition accuracy and the time efficiency.

• Geomechanics and Engineering
• /
• 제21권1호
• /
• pp.85-93
• /
• 2020

In this article, the generalized thermoelastic theory with fractional derivative is presented to estimate the variation of temperature, the components of stress, the components of displacement and the changes in volume fraction field in two-dimensional porous media. Easily, the exact solutions in the Laplace domain are obtained. By using Laplace and Fourier transformations with the eigenvalues method, the physical quantities are obtained analytically. The numerical results for all the physical quantities considered are implemented and presented graphically. The results display that the present model with the fractional derivative is reduced to the Lord and Shulman (LS) and the classical dynamical coupled (CT) theories when the fractional parameter is equivalent to one and the delay time is equal to zero and respectively.

• 영어영문학
• /
• 제64권1호
• /
• pp.135-150
• /
• 2018

Focusing on the hermeneutic instability of a key word of Paradise Lost, "wander," this study attempts to situate John Milton's early modern epic in the longue $dur{\acute{e}}e$ historical transition from seignorial to capitalist mode of production, especially the displacement and reorganization of producer population, a corollary of early phase of modernization. The historic experience of vagrancy and its normalization, and the concomitant shift of the primary human sociability from given to voluntary bonds, I suggest, shape and inform Milton's early modern rewriting of the Biblical story of the fall and his revising of the heroic epic romance into a plebeian romance of a wandering, companionate couple. While building on the critical consensus on this poem's deliberate distancing from the tradition of classical epic and chivalric romance, this essay argues that Milton re-appropriates and re-channels the aspirational aspect of chivalric wandering, or mobility, for his plebeian heroes, a companionate conjugal couple. The hermeneutic instability of the word wander, this essay suggests, captures the duality of the historic experience of vagrancy, both the tragic experience of displacement and the liberational and uplifting dimension of that experience.

• ETRI Journal
• /
• 제44권1호
• /
• pp.125-134
• /
• 2022

Visible light communication (VLC) systems incorporate ambient lighting and wireless data transmission, and the experienced channel in indoor VLC is a major topic that should be examined for reliable communication. In this study, it is realized that multiple transmitters in classical alignment are the forceful factors for channel characteristics. In the frequency band, fluctuations with sudden drops are observed, where the fluctuation shape is related to the source layout and receiver location. These varying frequency-selective channels need solutions, especially for mobile users, because sustained channel estimation and equalization are necessary as the receiver changes its location. It is proven that using light-emitting diodes (LEDs) with highly directional beams as sources or using a detector with a narrow field of view (FOV) in the receiver may help partially alleviate the problem; the frequency selectivity of the channel reduces in some regions of the room. For flat fading channel characteristics all over the room, LEDs should be aligned in hexagonal cellular structure, and detector FOV should be arranged according to the cell dimension outcomes.

• Advances in nano research
• /
• 제13권4호
• /
• pp.379-391
• /
• 2022

One factor that can heighten the risk of the rapture intracranial aneurysm (IA) is bifurcations, which can cause the IA to evaluate. This study presents the effect of geometric of intracranial vascular on the bifurcation analysis of the aneurysm occurrence. The aneurysm mechanism is mathematically modeled based on the nano pipe structures under the thermal stresses, and the impact of the aneurysm geometric on the stability and bifurcation points is analyzed. Because of the dimension of these structures, the classical theories could not predict their behavior perfectly, so the nonclassical and nonlocal theories are required for the mechanical modeling of the aneurysm. The presented results show that the bifurcation point of the aneurysm mechanism is dependent on the environment temperature, and the temperature change plays an essential role in the stability of these structures.

• 한국어류학회지
• /
• 제24권3호
• /
• pp.151-159
• /
• 2012

정교배체인 각시붕어, Rhodeus uyekii (♀)${\times}$떡납줄갱이, R. notatus (♂) 잡종, 그리고 상반교배체인 떡납줄갱이 (♀)${\times}$각시붕어(♂) 잡종을 대상으로 혈액도말을 통한 적혈구 크기, flowcytometry를 통한 세포유전학적인 형질 및 truss dimension과 classical dimension에 의한 외부 계측형질에서의 특성을 부모종간의 차이를 비교하였다. 각시붕어와 떡납줄갱이의 정교배체 및 상반교배체의 계측형질은 일반적으로 이들 유도시 사용된 모계와 부계 종의 중간을 보였다. 정교배체는 14개의 계측형질이 부계의 형질과 유사하였으며 7개의 계측형질이 모계의 형질과 유사하였다. 상반교배체의 경우, 13개의 계측형질이 부계의 형질을, 5개의 계측형질이 모계의 형질과 유사하였다. 정교배체와 상반교배체의 체색소 분포는 중간을 보이나 양친 종을 닮게 나타났다(P<0.05). 적혈구 크기와 DNA 함량은 정교배체와 상반교배체 모두 모계의 적혈구 크기 및 DNA 함량을 따르는 경향이 나타났다(P<0.05). 본 연구에서 파악된 각시붕어와 떡납줄갱이의 잡종 계측형질 및 세포유전학적인 형질은 납자루아과의 관상어 개발시 종간 구별에 유용할 것이다.