• 천문학회보
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• 제44권1호
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• pp.35.1-35.1
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• 2019

We present a statistical analysis on the spin-orbit alignment of dark matter halo pairs in cosmological simulations. The alignment is defined as the angular concurrence between the halo spin vector (${\vec{S}}$) and the orbital angular momentum vector (${\vec{L}}$) of the major companion. We identify interacting halo pairs with the mass ratios from 1:1 to 1:3, with the halo masses of 10.8 < $Log(M_{halo}/M_{sun}$) < 13.0, and with the separations smaller than a sum of their virial radii ($R_{12}<R_{1,vir}+R_{2,vir}$). Based on the total energy ($E_{12}$), the pairs are classified into flybys ($E_{12}$ > 0) and mergers ($E_{12}{\leq}0$). By measuring the angle (${\theta}_{SL}$) between ${\vec{S}}$ and ${\vec{L}}$, we confirm a strong spin-orbit alignment signal such that the halo spin is preferentially aligned with the orbital angular momentum of the major companion. We find that the signal of the spin-orbit alignment for the flyby is weaker than that for the merger. We also find an unexpected excess signal of the spin-orbit alignment at $cos{\theta}_{SL}{\sim}0.25$. Both the strength of the spin-orbit alignment and the degree of the excess depend only on the environment. We conclude that the halo spin is determined by the accretion in a preferred direction set by the ambient environment.

• 대한토목학회논문집
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• 제43권5호
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• pp.651-657
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• 2023

국내외 철도사업에서 철도의 신규 건설과 더불어 기존선의 개량을 통한 증속, 고속화 사업도 큰 비중을 차지고 있다. 특히 해외의 개발도상국은 경제수준을 고려할 때 고속철도의 건설은 막대한 규모의 예산소요와 수요를 고려할 때 한계가 있어, 기존 철도의 선형개량을 통한 증속사업이 실현가능성이 높은 것으로 판단하고 있다. 본 연구에서는 선형개량을 통향 기존선의 증속사업의 효율적 기획과 분석을 위하여, 기존에 신규 철도 건설사업 분석에 활용되고 있는 지능형 철도선형계획 프로그램(ei-Rail)에 선형개량사업 분석 기능을 추가할 수 있는 방법론을 개발하였다. 수치지도 또는 기존의 위성사진 자료를 기반의 베이스 맵에 기존의 철도선형을 입력하고, 목표속도등 선형개량사업의 목표를 입력하면, 사업의 비용과 도면, 증속효과 분석 결과 등을 자동적으로 제시함으로써, 철도선형개량 사업의 기획과 분석을 효율적으로 수행할 수 있는 도구로 활용될 수 있도록 하였다.

• 한국기계가공학회지
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• 제17권3호
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• pp.134-140
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• 2018

This paper describes the design and fabrication of an automatic alignment and loading system for workpieces. To move a workpiece to a chucking position of a machine tool using a gantry robot, an automatic aligning device is required to load the workpiece before machining and automatically align them. The automatic alignment system was conceptually designed, and the structural analysis was performed for the main parts such as the top plate, center support, front and back support, and support shaft. Based on the structural analysis results, the size of these structures was determined. The automatic alignment system was manufactured, and the vertical movement characteristics of the workpiece up-and-down movement device and the rotation characteristics of the workpiece rotation device were experimentally examined. The result has confirmed that they operate normally.

• 정보처리학회논문지B
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• 제19B권2호
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• pp.135-148
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• 2012

본 논문에서는 Predicate-Argument Tuple (PAT)를 기반으로 텍스트 간 심층적 근사 정렬(Approximate Alignment)을 통한 문장 단위 바꿔쓰기표현(sentential paraphrase) 식별 모델을 제안한다. 두 문장 간의 PAT 기반 근사 정렬 결과를 바탕으로, 두 문장의 의미적 연관성을 효과적으로 표현하는 다양한 정렬 자질(alignment feature)들을 정의함으로써, 바꿔쓰기표현 식별 문제를 지도 학습(supervised learning) 기반의 자동 분류 모델로 접근하였다. 실험을 통해서 제안 모델의 가능성을 확인할 수 있었으며, 시스템의 오류 분석을 통해 제안 방법이 아직 해결하지 못하는 다양한 바꿔쓰기표현 유형들을 식별함으로써 향후 시스템의 성능 개선 방향을 도출하였다.

• 한국정밀공학회지
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• 제20권2호
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• pp.40-49
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• 2003

Ferrule is widely used as fiber optic connecters. In fiber-optic communications. the shape accuracy such as coaxiality and cylindricity of ferrule affects insertion loss. When coaxial grinding of ferrule supported by two pin. pin alignment and chucking accuracy are very important. In this research, the kinematic behavior of the ferrule centers are investigated in the case where the ferrule is chucked with the cone-shaped center pins and bail centers, With homogeneous coordinate transformation and numerical analysis, the obtained results are as follows: In the case of cone-type center, the alignment errors between center pins alone do not affect the rotation accuracy of ferrule. The alignment errors between center holes cause sinusoidal displacement of ferrule. And the maximum displacement of ferrule centers is proportional to the center pin angle. In the case of ball-type center, the displacements of ferrule centers has similar pattern as cone-type center, and the alignment errors art proportional to ball diameters.

• 정보과학회 컴퓨팅의 실제 논문지
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• 제21권3호
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• pp.263-268
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• 2015

변종 악성코드는 그 기능에 있어 차이가 없으나 구조적인 차이가 존재하는 악성코드로, 같은 그룹으로 분류하여 처리하는 것이 유용하다. 변종 악성코드 분석을 위해 본 논문에서는 바이오인포매틱스 분야에서 사용하는 서열 정렬 기법을 사용하여 악성코드들의 API 호출 정보 간의 공통부분을 찾고자 하였다. 서열 정렬 기법은 API 호출 정보의 길이에 대해 의존적인 성능을 가지며, API 호출 정보의 길이가 커짐에 따라 성능이 매우 떨어진다. 따라서 본 논문에서는 서열 정렬 기법 적용 이전에 API 호출 정보에서 발견되는 반복 패턴을 제거하는 방법을 적용함으로써 성능이 보장될 수 있도록 하였다. 최종적으로 서열 정렬 기법을 통한 악성코드 간의 유사도를 구하는 방법에 대하여 논하였다. 또한 실제 악성코드 샘플에 대한 실험 결과를 제시하였다.

• 한국전문물리치료학회지
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• 제29권4호
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• pp.282-288
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• 2022

Background: Pilates exercises are used for body shape correction because they can achieve correct posture alignment through spinal stabilization. Objects: This study aimed to determine whether the use of reformers increases the effectiveness of Pilates core exercises on body alignment in standing. Methods: The study included 30 women without known diagnoses of musculoskeletal and neurological disorders or cancer. Those who had taken more than 10 Pilates lessons were excluded. The participants were randomly assigned to either the reformer exercise group or the mat exercise group, and interventional Pilates exercises were performed for 60 minutes a day, three times a week, for a total of 8 weeks. Ten movements of the reformer and mat Pilates core exercise programs were included. Exbody^® 9100 MOMI musculoskeletal analysis equipment (Exbody Inc.) was used to assess the alignment of the standing posture in the frontal plane. Results: As a result of comparing the differences within and between the groups before and after the intervention using the two-way mixed analysis of variance test, height differences in the head, pelvis, left and right, shoulders, scapulas, knees, and ankles in the frontal plane after the intervention were found in both groups. For example, the left-right symmetry of the body alignment in the standing posture was significantly improved within each group (p < 0.05). However, no significant difference was found between the groups (p > 0.05). Conclusion: Both the reformer and mat Pilates core exercises were effective for standing posture alignment, which has clinical significance. If an exercise program is developed based on the analysis of movements necessary for posture improvement and the target muscles to be strengthened, the same effect can be achieved only with mat exercise without using the reformer equipment at the beginner stage.

• Earthquakes and Structures
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• 제16권6호
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• pp.715-726
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• 2019

Several municipal seismic vulnerability investigations have been identified pounding of adjacent structures as one of the main hazards due to the constrained separation distance between adjacent buildings. Consequently, an assessment of the seismic pounding risk of buildings is superficial in future adjustment of design code provisions for buildings. The seismic lateral oscillation of adjacent buildings with eccentric alignment is partly restrained, and therefore a torsional response demand is induced in the building under earthquake excitation due to eccentric pounding. In this paper, the influence of the eccentric seismic pounding on the design demands for adjacent symmetric buildings with eccentric alignment is presented. A mathematical simulation is formulated to evaluate the eccentric pounding effects on the seismic design demands of adjacent buildings, where the seismic response analysis of adjacent buildings in series during collisions is investigated for various design parameters that include number of stories; in-plan alignment configurations, and then compared with that for no-pounding case. According to the herein outcomes, the effects of seismic pounding severity is mainly depending on characteristics of vibrations of the adjacent buildings and on the characteristics of input ground motions as well. The position of the building wherever exterior or interior alignment also, influences the seismic pounding severity as the effect of exposed direction from one or two sides. The response of acceleration and the shear force demands appear to be greater in case of adjacent buildings as seismic pounding at different levels of stories, than that in case of no-pounding buildings. The results confirm that torsional oscillations due to eccentric pounding play a significant role in the overall pounding-involved response of symmetric buildings under earthquake excitation due to horizontal eccentric alignment.

• The Journal of Korean Physical Therapy
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• 제16권2호
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• pp.17-21
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• 2004

We need to study about lower extremity alignment because the structure dictates the function of lower extremity. Through lower extremity alignment assessment in static posture, we recognize abnormal structural conditions which could affect dynamic motion such as gait. To evaluate of lower extremity alignment provide so many useful information, but method of measurement is so limited. Therefore, this review will assist understanding for measurement of lower extremity alignment in static posture. From now on study about the objective measurement method must be achieved much more in physical therapy.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.475-478
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• 2002

VA-LCDs is widely used for recent LCD productions owing to good viewing angle and high contrast. To apply for VA-LCDs, we have synthesized novel homeotropic alignment materials, which all generated high pretilt angles ($9^{\circ}$). The thermal stabilities of them were observed by thermogravimetric analysis (TGA). Transmittances of the NLC cell used the new alignment material were not changed before and after thermal annealing at $120^{\circ}C$ for 24hrs. In this work, the synthesis and alignment properties of new homeotropic alignment materials will be reported.