• Wind and Structures
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• 제23권4호
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• pp.275-300
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• 2016

Synchronous multi-pressure measurements were carried out with relatively long time duration for a double-layer reticulated shell roof model in the atmospheric boundary layer wind tunnel. Since the long roof is open at two ends for the storage of coal piles, three different testing cases were considered as the empty roof without coal piles (Case A), half coal piles inside (Case B) and full coal piles inside (Case C). Based on the wind tunnel test results, non-Gaussian time-dependent statistics of net wind pressure on the shell roof were quantified in terms of skewness and kurtosis. It was found that the direct statistical estimation of high-order moments and peak factors is quite sensitive to the duration of wind pressure time-history data. The maximum value of COVs (Coefficients of variations) of high-order moments is up to 1.05 for several measured pressure processes. The Mixture distribution models are proposed for better modeling the distribution of a parent pressure process. With the aid of mixture parent distribution models, the existing translated-peak-process (TPP) method has been revised and improved in the estimation of non-Gaussian peak factors. Finally, non-Gaussian peak factors of wind pressure, particularly for those observed hardening pressure process, were calculated by employing various state-of-the-art methods and compared to the direct statistical analysis of the measured long-duration wind pressure data. The estimated non-Gaussian peak factors for a hardening pressure process at the leading edge of the roof were varying from 3.6229, 3.3693 to 3.3416 corresponding to three different cases of A, B and C.

• Journal of information and communication convergence engineering
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• 제8권5호
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• pp.575-580
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• 2010

Eye gaze as a form of input was primarily developed for users who are unable to use usual interaction devices such as keyboard and the mouse; however, with the increasing accuracy in eye gaze detection with decreasing cost of development, it tends to be a practical interaction method for able-bodied users in soon future as well. This paper explores a low-cost, robust, rotation and illumination independent eye gaze system for gaze enhanced user interfaces. We introduce two brand-new algorithms for fast and sub-pixel precise pupil center detection and 2D Eye Gaze estimation by means of deformable template matching methodology. In this paper, we propose a new algorithm based on the deformable angular integral search algorithm based on minimum intensity value to localize eyeball (iris outer boundary) in gray scale eye region images. Basically, it finds the center of the pupil in order to use it in our second proposed algorithm which is about 2D eye gaze tracking. First, we detect the eye regions by means of Intel OpenCV AdaBoost Haar cascade classifiers and assign the approximate size of eyeball depending on the eye region size. Secondly, using DAISMI (Deformable Angular Integral Search by Minimum Intensity) algorithm, pupil center is detected. Then, by using the percentage of black pixels over eyeball circle area, we convert the image into binary (Black and white color) for being used in the next part: DTBGE (Deformable Template based 2D Gaze Estimation) algorithm. Finally, using DTBGE algorithm, initial pupil center coordinates are assigned and DTBGE creates new pupil center coordinates and estimates the final gaze directions and eyeball size. We have performed extensive experiments and achieved very encouraging results. Finally, we discuss the effectiveness of the proposed method through several experimental results.

• KIEAE Journal
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• 제13권5호
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• pp.17-22
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• 2013

This study aims at proposing a sound and sustainable development direction of an urban commercial district by identifying space syntactic properties, from the perspective of human ecology, of the street network in Enuengjeongi culture street as the representative commercial district of Daejeon City in Korea. The results are obtained through Angular Segment Analysis (ASA) on the street network in subject area for this study. It was found that most of the socially integrated nodes are arranged along the axis of main street in the district. However, in some of those nodes, it was investigated that the social integrative function have weakened, because open spaces as public space for the general public are occupied illegally by commercial purposes of shops and car parking. It was found that the socially isolated nodes are located at the district boundary connected to a relative narrow street, with a relatively low density of the commercial facilities. Besides, it was identified that a street width in the commercial district may be a factor affecting the social integration of a space on the basis of the openness of the space.

• 한국해양학회지
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• 제28권4호
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• pp.292-304
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• 1993

세밀한 격자망과 정교한 개방경계 조건을 적용하고 실측 수온 염분치를 직접표층 에 적용하여 동해순환을 수치 모델화 하였다. 동해의 특징적인 현상들이 성공적으로 재현되었으며 특히 북한 한류와 동한난류가 더욱 뚜렷하여 졌다. 특기할 만한 사실로 는 울릉난수괴와 중층 저염분수가 재현되었다는 것이다. 전자는 동한난류의 바깥쪽에 서 국지적으로 생성된 시계방향의 재순환류와 연관되어 있고 후자는 동해 북, 북서 연 안역에서 침강으로 형성되어 강한 중층해류에 의해 연안을 따라 남족으로 이동된다. 모델에서는 또한 일본 연안류가 강한 계절변화를 보여서 겨울에는 순압, 여름에는 경 압구조를 나타냄을 보였으며 이 때 여름에 나타나는 강한 중층 반류가 흥미롭다. 모델 에서는 또한 동해 순환의 거시적 특징을 지워 주는데 북쪽의 반시계 방향 순환역과 남 쪽의 시계방향 순환역이 그것이다. 이들은 동해에서 국지적인 순환역학의 중요성을 시 사한다. 그러나 본 모델에서는 동한난류의 이안점이 실제보다 북쪽에 치우쳐서 나타나 는 것을 완전히 해결하지는 못하였다.

• Steel and Composite Structures
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• 제20권5호
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• pp.1023-1042
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• 2016

Based on Hamilton's principle, the flexural vibration differential equations and boundary conditions of the steel-concrete composite beam (SCCB) with comprehensive consideration of the influences of the shear deformation, interface slip and longitudinal inertia of motion were derived. The analytical natural frequencies of flexural vibration were compared with available results previously observed by the experiments, the results calculated by the FE model and the other similar beam theories available in the open literatures. The comparison results showed that, the calculation results of the analytical and Timoshenko models had a good agreement with the results of the experimental test and FE model. Finally, the influences of shear deformation and interface slip on the flexural natural frequencies of the SCCB were discussed. The shear deformation effect increases with the increase of the mode orders of flexural natural vibration, and the flexural natural frequencies of the higher mode orders ignoring the influence of shear deformations effect would be overestimated. The interface slip effect decrease with the increase of the mode orders of flexural natural vibration, and the influence of the interface slip effect on flexural natural frequencies of the low mode orders is significant. The influence of the degree of shear connection on shear deformation effect is insignificant, and the low order modes of flexural natural vibration are mainly composed of the rotational displacement of cross sections.

• 소음진동
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• 제9권1호
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• pp.206-213
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• 1999

선박의 보-유추 진동해석에 있어 2차원 부가수질량의 3차원 효과를 고려하기 위해서 3차원 수정계수(J-factor)를 계산해야 하는데 광폭선의 경우에는 J-factor의 계산이 부정확하고 번거롭다. 이 논문에서는 이를 개선하기 위해 새로운 선박의 보-유추 접수진동해석 방법을 소개하였다. 이 방법은 선박에 접수된 유체에 대해 BEM 기법을 이용하여 3차원 유체력을 직접 계산하고 이를 일정 간격으로 나눈 각 스트립에 집중질량으로 평가한 후에 선체의 보모델과 결합하여 보-유추 진동해석을 수행하는 방법이다. 오픈탑 컨테이너선의 모델에 대해 기존의 보-유추 진동해석방법과 이 논문에서 제시한 새로운 진동해석방법을 이용하여 진동해석을 수행하고 가진 실험에 의한 진동계측결과와 상호 비교함으로써 새로운 방법의 유용성을 검증하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권5호
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• pp.723-727
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• 2005

Ghrelin is a novel growth-hormone-releasing acylated peptide, which has been purified and identified in rat stomach. In the present study, the full-length sequence of bovine ghrelin cDNA was cloned by RT-PCR. The bovine ghrelin cDNA sequence derived in the present study included a 348 bp open reading frame and a 137 bp 3'UTR. The putative amino acid sequence of bovine prepro-ghrelin consisted of 116 amino acids, which contained the 27-amino acid ghrelin. The sequence analysis of the bovine ghrelin gene revealed that an intron existed between Gln$^{13}$ and Arg$^{14}$ of ghrelin. This exon-intron boundary matched the GT-AG rule of the splicing mechanism. Compared with rats, which have two tandem CAG sequences in the 3'end of intron, bovine ghrelin genome has only one CAG sequence. Therefore, although rats can produce 28 amino acid-ghrelin and 27 amino acid-des-Gln$^{14}$-ghrelin by alternative splicing, ruminant species, including bovines, might be able to produce only one type of ghrelin peptide, des-Gln$^{14}$-ghrelin. The influence of aging on plasma ghrelin concentration was also examined. Plasma ghrelin concentration increased after birth to approximately 600 days of age, and then remained constant.

• 복식
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• 제60권5호
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• pp.117-127
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• 2010

In this study, hyperspace is a result of imagination created by means of facts and fiction, represents a transfer to determination and indetermination, and means an extension to an open form. In other words, hyperspace is a high dimensional space expanded to imagination through the combination of the viewpoint on facts in this dimension and fiction. When the 2D plane surface or 3D symmetry is destroyed, or when the frame is twisted or entangled, the non-Euclidean geometry is created eventually. And when the twisting leads to transmutation and the destruction of the form reaches the extreme; this in turn became the twisting like Mbius band. Likewise, the non-Euclidean geometry is co-related to the asymmetry of the Higgs mechanism. When the 'destruction of symmetry' is considered, symmetric theory and asymmetric world can be connected. The asymmetry in turn can maintain balance by arranging the uneven weights at different distances from the shaft. Moreover, at this the concept of the upper, lower, left and right, which was included in the original form, may be crumbled down. The destruction of the symmetry is essential in order to present forecast that coincides with the phenomenon of the real world. Non-Euclidean geometry characteristic is expressed by asymmetry, twists, and deconstruction and its representative characteristic is ambiguity. The boundary between the front, back, upper, lower, inner and outer is unclear, and it is difficult and vague to pinpoint specific location. The design that does not clearly define or determine the direction of wearing costume is indeed the non-oriented design that can be worn without getting restricted by specific direction such as front and back. Non-Euclidean geometry characteristic of hyperspace have been applied to create new shapes through the modification of the substance from traditional clothing of the eastern world to modern fashion. The way of thinking in the 'hyperspace' that used to be expressed in the costumes of the east and the west in the past became the forum for unlimited creation.

• 한국생산제조학회지
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• 제19권6호
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• pp.883-888
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• 2010

This study have goal with conceptual design for Offshore Structures of high pressure control valve for localization. Ball valve for development accomplished with flow analysis based on provision of ANSI B16.34, ANSI B16.10, ANSI B16.25 In order to localize the Offshore Structures high pressure control valve. Numerical simulation using CFD (Computational Fluid Dynamic) in order to predict a mass flow rate and a flow coefficient form flow dynamic point of view. The working fluid assumed the glycerin (C3H8O3). The valve inlet and outlet setup a pressure boundary condition. The outlet pressure was fixed by atmospheric pressure and calculated until increasing 1bar to 10bar. CFD analysis used STAR-CCM+ which is commercial code and Governing equations were calculated by moving mesh which is rotated 90 degrees when ball valve operated opening and closing in 1 degree interval. The result shows change of mass flow rate according to opening and closing angle of valve, Flow decrease observed open valve that equal percentage flow paten which is general inclination of ball valve. Relation with flow and flow coefficient can not be proportional according to inlet pressure when compare with mass flow rate. Because flow coefficient have influence in flow and pressure difference. Namely, flow can be change even if it has same Cv value. The structural analysis used ANSYS which is a commercial code. Stress analysis result of internal pressure in valve showed lower than yield strength. This is expect to need more detail design and verification for stem and seat structure.

• 대한수학회지
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• 제57권3호
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• pp.747-775
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• 2020

In this work we investigate the nonlocal elliptic equation with critical Hardy-Sobolev exponents as follows, $$(P)\;\{(-{\Delta}_p)^su={\lambda}{\mid}u{\mid}^{q-2}u+{\frac{{\mid}u{\mid}^{p{^*_s}(t)-2}u}{{\mid}x{\mid}^t}}{\hspace{10}}in\;{\Omega},\\u=0{\hspace{217}}in\;{\mathbb{R}}^N{\backslash}{\Omega},$$ where Ω ⊂ ℝ^N is an open bounded domain with Lipschitz boundary, 0 < s < 1, λ > 0 is a parameter, 0 < t < sp < N, 1 < q < p < p^∗_s where $p^*_s={\frac{N_p}{N-sp}}$, $p^*_s(t)={\frac{p(N-t)}{N-sp}}$, are the fractional critical Sobolev and Hardy-Sobolev exponents respectively. The fractional p-laplacian (-∆_p)^su with s ∈ (0, 1) is the nonlinear nonlocal operator defined on smooth functions by $\displaystyle(-{\Delta}_p)^su(x)=2{\lim_{{\epsilon}{\searrow}0}}\int{_{{\mathbb{R}}^N{\backslash}{B_{\epsilon}}}}\;\frac{{\mid}u(x)-u(y){\mid}^{p-2}(u(x)-u(y))}{{\mid}x-y{\mid}^{N+ps}}dy$, x ∈ ℝ^N. The main goal of this work is to show how the usual variational methods and some analysis techniques can be extended to deal with nonlocal problems involving Sobolev and Hardy nonlinearities. We also prove that for some α ∈ (0, 1), the weak solution to the problem (P) is in C^1,α(${\bar{\Omega}}$).