• 제목/요약/키워드: Irregularity

검색결과 848건 처리시간 0.021초

단면형상 분석을 이용한 요철이 심한 금석문(金石文) 판독 향상 방법 연구 (A Study on Readability Improvement Method for Ancient Inscription of Irregularity Surface using Cross Section Analysis)

  • 최원호;고선우
    • 한국IT서비스학회지
    • /
    • 제13권2호
    • /
    • pp.251-259
    • /
    • 2014
  • Outdoor cultural properties have been damaged by natural weathering and air pollution for a long time. For this reason, there are many characteristics it is hard to decipher some carved inscription on the surface of damaged outdoor cultural properties. Until now, Rubbed copy has been widely used to decode engraved inscription. A investigation for epigraph has been made by the rubbing that has resulted in a lower resolution from the viewpoints of extraction process and used materials. Rubbing's results are not satisfied in the damaged inscriptions which are weathered by natural environment and pollution for a long time and in the narrowed one. The main analysis presented in this paper is a cross section analysis method using 3d scanning technique for epigraph not read. Cross section analysis is a study on readability improvement method for ancient inscription of irregularity monument surface. Cross section analysis confirms information that separated the inscription information of monument and the ground information to read a ancient inscription and decode the inscription information. The proposed character identification method contributed to decoding an ancient inscription on Silla Monument in Jungseong-ri of Pohang.

Extension of Direct Displacement-Based Design to Include Higher-Mode Effects in Planar Reinforced Concrete Frame Buildings

  • 아베베 베카 하일루;이종세
    • 한국지진공학회논문집
    • /
    • 제22권5호
    • /
    • pp.299-309
    • /
    • 2018
  • Now that problems with force-based seismic design have been clearly identified, design is inclined toward displacement-based methods. One such widely used method is Direct-Displacement-Based Design (DDBD). Yet, one of the shortcomings of DDBD is considering higher-mode amplification of story shear, moments, and displacements using equations obtained from limited parametric studies of regular planar frames. In this paper, a different approach to account for higher-mode effects is proposed. This approach determines the lateral secant stiffness of the building frames that fulfill the allowable inter-story drift without exceeding the desired story displacements. Using the stiffness, an elastic response spectrum analysis is carried out to determine elastic higher-mode force effects. These force effects are then combined with DDBD-obtained first-mode force effects using the appropriate modal superposition method so that design can be performed. The proposed design procedure is verified using Nonlinear Time History Analysis (NTHA) of twelve planar frames in four categories accounting for mass and stiffness irregularity along the height. In general, the NTHA response outputs compared well with the allowable limits of the performance objective. Thus, it fulfills the aim of minimizing the use of NTHA for planar frame buildings, thereby saving computational resources and effort.

부정맥(不整脈)에 대한 동의보감(東醫寶鑑)의 판단기준 연구(硏究) (A Study of Judgment for Irregular Pulses Referred in Donguibogam(東醫寶鑑))

  • 조미정;정현종
    • 한국의사학회지
    • /
    • 제26권2호
    • /
    • pp.63-74
    • /
    • 2013
  • Objective : In Donguibogam(東醫寶鑑), like a slow pulse with irregular intervals(結脈), an abrupt pulse(促脈) and a slow and weak pulse with regular intervals(代脈), an uneven pulse is written as a kind of arrhythmia. Such a recognition differs from the present one. In this study, I try to seize the meaning and deliberate whether those expressions are appropriate. Method : 1. Collect and compare the materials of the above four pulses among documentary records of feeling the pulse for diagnosis. 2. Grasp the aspect and trend of changes. 3. Reason whether records in Donguibogam(東醫寶鑑) are proper or not. Result & Conclusions : Donguibogam(東醫寶鑑) written "like a slow pulse with irregular intervals(結脈), an abrupt pulse(促脈) and a slow and weak pulse with regular intervals(代脈), an uneven pulse is written as a kind of arrhythmia". It is not 'an uneven pulse' is written about irregularity of pulse, but 'an uneven pulse' is written about irregularity of the sense able to be felt on the fingertip.

현대 패션에 나타난 주름의 조형적 특성에 관한 연구 -라이프니츠와 들뢰즈를 중심으로- (A Study on the Formative Characteristics of the Pleats Expressed in Modern Fashion -Focusing on the Thought of G.W.Leifniz and G.Deleuze-)

  • 양희영;양숙희
    • 복식
    • /
    • 제57권1호
    • /
    • pp.130-146
    • /
    • 2007
  • Thought of postmodernism accepted between variety and differentiation is characterized by variability and indeterminacy aimed at continuous change. For that reason, modern fashion has been grouping a lot of manners for creation of the various different form and structure. This paper studies the characteristics of the folding system, which expands efficiency of the spatial utility and shows various forms. Folding system expressed in modern fashion could be divided the pleats, which were made of the folding, and the dreaperies, which were made of bending. This selects the pleats as a enlarged concept of the folding system that contains between the former and the letter. Pleats did not mean two dimensional folding surfaces, but three dimensional spatial structures. For understanding of the folding system as a three dimensional spatial structure, this is utilized with the thought of the 'le pli' of G.W.Leifniz and G.Deleuze. The pleats expressed in modern fashion can subdivided into 4 sets; crinkle system, origami system, fractal pleats by folding system, and drapery system. And Formative characteristics of the pleats are analyzed with enlargement, fluidity, deconstruction, irregularity.

타원의 치형 형상을 갖는 로터 설계 자동화 시스템 개발 (Development of an Automated Design System for Oil Pumps with Ellipse Lobe Profile)

  • 정성윤;한승무;김철
    • 한국정밀공학회지
    • /
    • 제26권1호
    • /
    • pp.120-129
    • /
    • 2009
  • An internal lobe pump is suitable for oil hydraulics of machine tools, automotive engines, compressors, constructions and other various applications. In particular, the pump is an essential machine element of an automotive engine to feed lubricant oil. The subject of this paper is the theoretical analysis of internal lobe pump whose the main components are the rotors: usually the outer one is characterized by lobes with elliptical shape, while the inner rotor profile is determined as conjugate to the other. And the integrated system which is composed of three main modules has been developed through AutoLISP under AutoCAD circumstance. It generates new lobe profile and calculates automatically the flow rate and flow rate irregularity according to the lobe profile generated. Results obtained from the analysis enable the designer and manufacturer of oil pump to be more efficient in this field.

Crack identification with parametric optimization of entropy & wavelet transformation

  • Wimarshana, Buddhi;Wu, Nan;Wu, Christine
    • Structural Monitoring and Maintenance
    • /
    • 제4권1호
    • /
    • pp.33-52
    • /
    • 2017
  • A cantilever beam with a breathing crack is studied to improve the breathing crack identification sensitivity by the parametric optimization of sample entropy and wavelet transformation. Crack breathing is a special bi-linear phenomenon experienced by fatigue cracks which are under dynamic loadings. Entropy is a measure, which can quantify the complexity or irregularity in system dynamics, and hence employed to quantify the bi-linearity/irregularity of the vibration response, which is induced by the breathing phenomenon of a fatigue crack. To improve the sensitivity of entropy measurement for crack identification, wavelet transformation is merged with entropy. The crack identification is studied under different sinusoidal excitation frequencies of the cantilever beam. It is found that, for the excitation frequencies close to the first modal frequency of the beam structure, the method is capable of detecting only 22% of the crack depth percentage ratio with respect to the thickness of the beam. Using parametric optimization of sample entropy and wavelet transformation, this crack identification sensitivity is improved up to 8%. The experimental studies are carried out, and experimental results successfully validate the numerical parametric optimization process.

Fundamental period of infilled RC frame structures with vertical irregularity

  • Asteris, Panagiotis G.;Repapis, Constantinos C.;Foskolos, Filippos;Fotos, Alkis;Tsaris, Athanasios K.
    • Structural Engineering and Mechanics
    • /
    • 제61권5호
    • /
    • pp.663-674
    • /
    • 2017
  • The determination of the fundamental period of vibration of a structure is essential to earthquake design. Current codes provide formulas for the approximate estimation of the fundamental period of earthquake-resistant building systems. These formulas are dependent only on the height of the structure or number of storeys without taking into account the presence of infill walls into the structure, despite the fact that infill walls increase the stiffness and mass of the structure leading to significant changes in the fundamental period. Furthermore, such a formulation is overly conservative and unable to account for structures with geometric irregularities. In this study, which comprises the companion paper of previous published research by the authors, the effect of the vertical geometric irregularities on the fundamental periods of masonry infilled structures has been investigated, through a large set of infilled frame structure cases. Based on these results, an attempt to quantify the reduction of the fundamental period due to the vertical geometric irregularities has been made through a proposal of properly reduction factor.

제로터 오일 펌프 로버형상에 관한 최적설계 (Optimum design on the lobe shapes of Gerotor Oil Pump)

  • 김재훈;김창호;김철
    • 한국정밀공학회지
    • /
    • 제23권4호
    • /
    • pp.124-131
    • /
    • 2006
  • A gerotor pump is suitable for oil hydraulics of machine tools, automotive engines, compressors, constructions and other various applications. Especially the pump is an essential machine element of an automotive engine to feed lubricant oil. The subject of this paper is the theoretical analysis of internal lobe pump whose the main components are the rotors: usually the outer one is characterized by lobes with circular shape, while the inner rotor profile is determined as conjugate to the other. For this reason the first topic presented here is the definition of the geometry of the rotors starting from the design parameters. The choice of these parameters is subject to some limitations in odor to limit the pressure angle between the rotors. Now we will consider the design optimization. The first step is the determination of the instantaneous flow rate as a function of the design parameter. This allows us to calculate three performance indexes commonly used far the study of positive displacement pumps: the flow rate irregularity, the specific flow rate, and the specific slipping. These indexes are used to optimize the design of the pump and to obtain the sets of optimum design parameter. Results obtained from the analysis enable the designer and manufacturer of oil pump to be more efficient in this field, and the system could serve as a valuable one for experts and as a dependable training aid for beginners.

Finite element analysis of vehicle-bridge interaction by an iterative method

  • Jo, Ji-Seong;Jung, Hyung-Jo;Kim, Hongjin
    • Structural Engineering and Mechanics
    • /
    • 제30권2호
    • /
    • pp.165-176
    • /
    • 2008
  • In this paper, a new iterative method for solving vehicle-bridge interaction problems is proposed. Iterative methods have advantages over the non-iterative methods in that it is not necessary to update the system matrix for a given wheel location, and the method can be applied for a new type of car or bridge with few or no modifications. In the proposed method, the necessity of system matrices update is eliminated using the equivalent interaction force acting on the bridge, which is obtained iteratively. Ballast stiffness is included in the interaction forces and the geometric compatibility at the contact points are used as convergence criteria. The bridge is considered as an elastic Bernoulli-Euler beam with surface irregularity and ballast stiffness. The moving vehicle is modeled as a multi-axle mass-spring-damper system having many degrees of freedom depending on the number of axles. The pitching effect, which is the interaction effect between the rear and front wheels when a vehicle begins to enter or leave the bridge, is also considered in the formulation including extended ground boundaries having surface irregularity and ballast stiffness. The applicability of the proposed method is illustrated in the numerical studies.

Nonlinear Quality Indices Based on a Novel Lempel-Ziv Complexity for Assessing Quality of Multi-Lead ECGs Collected in Real Time

  • Zhang, Yatao;Ma, Zhenguo;Dong, Wentao
    • Journal of Information Processing Systems
    • /
    • 제16권2호
    • /
    • pp.508-521
    • /
    • 2020
  • We compared a novel encoding Lempel-Ziv complexity (ELZC) with three common complexity algorithms i.e., approximate entropy (ApEn), sample entropy (SampEn), and classic Lempel-Ziv complexity (CLZC) so as to determine a satisfied complexity and its corresponding quality indices for assessing quality of multi-lead electrocardiogram (ECG). First, we calculated the aforementioned algorithms on six artificial time series in order to compare their performance in terms of discerning randomness and the inherent irregularity within time series. Then, for analyzing sensitivity of the algorithms to content level of different noises within the ECG, we investigated their change trend in five artificial synthetic noisy ECGs containing different noises at several signal noise ratios. Finally, three quality indices based on the ELZC of the multi-lead ECG were proposed to assess the quality of 862 real 12-lead ECGs from the MIT databases. The results showed the ELZC could discern randomness and the inherent irregularity within six artificial time series, and also reflect content level of different noises within five artificial synthetic ECGs. The results indicated the AUCs of three quality indices of the ELZC had statistical significance (>0.500). The ELZC and its corresponding three indices were more suitable for multi-lead ECG quality assessment than the other three algorithms.