• Title/Summary/Keyword: Intensity of elements

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Design of phase-only diffractive pattern elements using a two-stage iterative Fourier transform algorithm (2단계 iterative Fourier transform 알고리즘을 이용한 위상형 회절무늬소자 설계)

  • 정필호;조두진
    • Korean Journal of Optics and Photonics
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    • v.11 no.1
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    • pp.47-57
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    • 2000
  • A two-stage iterative Fourier transform algorithm, based on hybrid input-output algorithm and new Pnoise algorithm, is used to design continuous and quantized phase-only diffractive pattern elements which produce arbitrary given intensity patterns via Fraunhofer diffraction. Numerical results for two $128\times128$ binary patterns and two grayscale patterns are compared with those of other algorithms. It is found that the algorithm yields better signal-to-noise ratio and even better uniformity with slightly lower diffraction efficiency than other algorithms. We investigated the dependence of performance on parameters used in the algorithm, size of noise region, and the number of phase levels for quantized elements. In the case of quantized phase elements, the size of noise region plays a greater role in determining the performance of the algorithm than given intensity pattern itself. tself.

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Intensity of Physical Therapy for Stroke (뇌졸중 환자를 위한 물리치료 강도)

  • Shin, Jae-Wook;Kim, Jae-Yong;Kim, Jwa-Jun
    • PNF and Movement
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    • v.11 no.1
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    • pp.35-42
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    • 2013
  • Purpose : This paper reviews intensity of physical therapy for stroke. Methods : This is literature study with Pubmed, EBSCO, ProQuest, EMBASE and CINAHL. Results : There were 20 studies that reviewed effects of increased intensity of physical therapy after stroke involving time post-stroke, elements of physical therapy, duration of physical therapy, methods of physical therapy. Ten of the eleven studies, involving time post-stroke, demonstrated significant improvement. Seventeen studies involving upper extremity, lower extremity and mobility demonstrated significant improvement. Five studies involving increased duration of physical therapy demonstrated significant improvement. Studies involving methods of physical therapy showed that mix of different methods is more effective than single method. Conclusion : Increased intensity of physical therapy improve functional recovery.

An Experimental Study on the Characteristic of Bearings with a Defect using the Sound-Intensity Technique (음향 인텐시티를 이용한 결함이 있는 베어링의 특성에 관한 실험적 연구)

  • 이해철;김명균;안기순;차경옥
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1999.05a
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    • pp.222-228
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    • 1999
  • The two-microphone sound-intensity technique has been used for the detection of defects in radially loaded ball bearings. The difference in the sound-intensity levels measured for bearings with no defect and for those with intentionally introduced defects of different sizes in their elements under various operating conditions of loads and speeds is demonstrated. A change in the intensity frequency spectrum because of the defects is observed. The results show that the detectability of an outer-race defect is much better than that of on inner-race or ball defect. It is difficult to detect defects at lower speeds. Sound-pressure measurements were also performed fur comparison, and it is shown that the detectability of defects by sound-intensity measurements is better than that by sound-pressure measurements.

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An Experimental Study of the Application of the Sound-Intensity Technique on the Detection of Defect in Rolling Bearings (굴림 베어링 요소의 결함 검출시 음향 인텐시티기술적용에 관한 실험적 연구)

  • 차경옥
    • Journal of Advanced Marine Engineering and Technology
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    • v.23 no.4
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    • pp.473-479
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    • 1999
  • The two-microphone sound-intensity technique has been used for the detection of defects in ra-ally loaded ball bearings. The difference in the sound-intensity levels measured for bearings with no defect and for those with intentionally introduced defects of different sizes n heir elements under various operating conditions of loads and speeds is demonstrated. The results show that of an inner-race or ball defect. It is difficult to detect defects at lower speeds. Sound-pressure measurements were also performed for comparison and it shown that the detectability of defects by sound-intensity measurements is better than that by sound-pressure measurements.

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Two new triangular finite elements containing stable open cracks

  • Rezaiee-Pajand, Mohammad;Gharaei-Moghaddam, Nima
    • Structural Engineering and Mechanics
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    • v.65 no.1
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    • pp.99-110
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    • 2018
  • The focus of this paper is on the elements with stable open cracks. To analyze plane problems, two triangular elements with three and six nodes are formulated using force method. Flexibility matrices of the elements are derived by combining the non-cracked flexibility and the additional one due to crack, which is computed by utilizing the local flexibility method. In order to compute the flexibility matrix of the intact element, a basic coordinate system without rigid body motions is required. In this paper, the basic system origin is located at the crack center and one of its axis coincides with the crack surfaces. This selection makes it possible to formulate elements with inclined cracks. It is obvious that the ability of the suggested elements in calculating accurate natural frequencies for cracked structures, make them applicable for vibration-based crack detection.

Evaluation of stress intensity factor for a crack normal to bimaterial interface using cubic isoparametric finite elements (3차 등매개 유한요소를 이용한 이종재료 접합면에 수직인 균열의 응력확대계수 평가)

  • Lim, Won-Gyun;Jeong, Gyu-Cheol;Song, Chi-Hun
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.22 no.1
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    • pp.206-214
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    • 1998
  • When a crack meets bimaterial interface stress singularity depends on the elastic constants of the adjacent materials. In the present study we are going to describe the finite element formulation for problems with a crack to be embedded in the stiffer material$({\mu}_2/{\mu}_1)$. The cubic isoparametric singular element, represented by adequately shifting the mid-side nodes adjacent to the crack tip is constructed to enclose the crack tip. An alternative method to obtain the optimal position of the mid-side nodes of cubic isoparametric elements is presented. In addition, a proper definition for the stress intensity factors of a crack normal to bimaterial interface is provided. It is based upon near a tip displacement solutions. Models for numerical analysis are two dimensional elastic bodies with a through crack under plain strain. The results obtained are compared with the previous solutions.

Automation of Analysis for Stress Intensity Factor of 3-D Cracks (3차원 균열의 응력확대계수에 대한 해석의 자동화)

  • 이준성
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1997.04a
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    • pp.496-500
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    • 1997
  • This paper describes an automated system for analyzing the stress intensity factors(SIFs) of three-dimensional (3D) cracks. A geometry model, i.e.a solid containing one or several 3D cracks is defined. Several distributions of local node density are chosen, and then automatically superposed on one another over the geometry model by using the fuzzy knowledge processing. Nodes are generated by the bucketing method, and ten-noded quadratic tetrahedral solid elements are generated by the Delauuay triangulation techniques. The singular elements such that the mid-point nodes near crack fornt are shifted at the quarter-points are automatically placed along the 3D crack front. THe complete finite element (FE) model generated, i.e the mesh with material properties and boundary conditions is given to one of the commercial FE codes, and a stress analysis is performed. The SIFs are calculated using the displacement extrapolation method. To demonstrate practical performance of the present system, a semi- elliptical surface crack in a plate subjected to tension is solved.

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Perceptions of Moral Intensity and Professional Commitment Towards Intention to Whistleblowing: Empirical Evidence from Malaysian Public Sector Organisations

  • MOHD ZEAMLEE, Siti Nurain;ALI, Mazurina Mohd;HASNAN, Suhaily
    • The Journal of Asian Finance, Economics and Business
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    • v.9 no.6
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    • pp.53-67
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    • 2022
  • The study's goal is to look at the factors that influence people's willingness to whistleblow in the Malaysian public sector by applying two elements from the Moral Intensity Theory: the magnitude of consequences and societal consensus with professional commitment as an additional variable. The cross-sectional study used primary data collection through questionnaires adopted from previous studies. The survey questionnaires were distributed to target respondents from 27 ministries in Malaysian public sectors selected based on their grade positions in the departments ranging from Grade 29 and above. The findings revealed that societal consensus and professional commitments significantly impact the intention to whistleblow. The findings imply that closed people's opinions may have certain persuasive elements that influence the act of whistleblowing as a moral and ethical activity, thereby increasing their whistleblowing intention. The results also suggest that when individuals are more committed to their career and organization, they will act ethically and under the professional norm, hence, they will be inclined to whistleblow. On the other hand, the magnitude of consequences suggested an insignificant relationship with the intention to whistleblow. The results could facilitate the government in curbing the whistleblowing issue by defining its root before the implementation of necessary policies.

New optimization method of patch shape to improve the effectiveness of cracked plates repair

  • Bouchiba, Mohamed S.;Serier, Boualem
    • Structural Engineering and Mechanics
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    • v.58 no.2
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    • pp.301-326
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    • 2016
  • An optimization method of patch shape was developed in this study, in order to improve repair of cracked plates. It aimed to minimize three objectives: stress intensity factor, patch volume and shear stresses in the adhesive film. The choice of these objectives ensures improving crack repair, gaining mass and enhancing the adhesion durability between the fractured plate and the composite patch. This was a multi-objective optimization combined with Finite elements calculations to find out the best distribution of patch height with respect to its width. The implementation of the method identified families of optimal shapes with specific geometric features around the crack tip and at the horizontal end of the patch. Considerable mass gain was achieved while improving the repair efficiency and keeping the adhesive shear stress at low levels.

Allocation of energy and nutrients in phaseolus multiflorus willd. on environmental gradients (환경구배에 따른 붉은강남콩 ( Phaseolus multiflorus Willd. ) 의 에너지와 무기원소의 분배)

  • Kim, Ok-Kyung
    • The Korean Journal of Ecology
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    • v.15 no.4
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    • pp.345-354
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    • 1992
  • Allocation patterns of energy and mineral elements were investigated with phaseolus multiflorus grown in the environmental gradients. The result showed different energy allocation patterns according to relative light intensities and nutrients. The optimal switching time of energy allocation from vegetative to resproductive growth was delated as decreasing relative light intensity. The switch of the shift to reproduction was timed earlier in phosphorus treatment and delayed in nitrogen treatment. Analyzing the mineral elements to various organs, patterns of energy allocation were different from those of mineral allocation. There was no significant difference for allocation patterns in relative light intensity gradients. it was shown that n and p were distributed over the reproductive organs, k mainly in stems, ca in leaves and na in roots. mg was evenly distributed in each organs.

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