Investigation of Impact Profile and Isolation Effect in Automated Impact Device Design and Control for Operational Modal Analysis

2015 ◽  
Vol 137 (9) ◽  
Author(s):  
Z. C. Ong ◽  
C. C. Lee
Keyword(s):  
Modal Analysis ◽  
Isolation Effect ◽  
Time Averaging ◽  
Impact Device ◽  
Lack Of Information ◽  
Analysis Technique ◽  
And Control ◽  
Phase Angles ◽  
Synchronous Time

A novel modal analysis technique called impact-synchronous modal analysis (ISMA) was introduced in previous research. With the utilization of impact-synchronous time averaging (ISTA), this modal analysis can be performed in presence of ambient forces whereas the conventional analysis method requires machines to be totally shut down. However, lack of information of phase angles with respect to impact in ISMA has caused it to be labor-intensive and time-consuming. An automated impact device (AID) is introduced in this study in the effort to replace the manually operated impact hammer and prepare it to be used in the current practice of ISMA on the purpose of enhancing its effectiveness and practicability. Impact profile and isolation effect are noted to be the contributing parameters in this study. This paper devoted on calibrating and controlling of the AID which gives the desired impact profiles as compared to the manual impact hammer. The AID is found effective in the determination of dynamic characteristics when the device is isolated from the boundary condition of the test structure.

scholarly journals Dynamic Modal Analysis of Vertical Machining Centre Components

2009 ◽  
Vol 2009 ◽  
pp. 1-10 ◽  
Author(s):  
Anayet U. Patwari ◽  
Waleed F. Faris ◽  
A. K. M. Nurul Amin ◽  
S. K. Loh
Keyword(s):  
Modal Analysis ◽  
Mode Shape ◽  
Modal Testing ◽  
Machine Component ◽  
Vibration Modes ◽  
Structural Dynamic ◽  
Element Simulation ◽  
Analysis Technique ◽  
Design Software

The paper presents a systematic procedure and details of the use of experimental and analytical modal analysis technique for structural dynamic evaluation processes of a vertical machining centre. The main results deal with assessment of the mode shape of the different components of the vertical machining centre. The simplified experimental modal analysis of different components of milling machine was carried out. This model of the different machine tool's structure is made by design software and analyzed by finite element simulation using ABAQUS software to extract the different theoretical mode shape of the components. The model is evaluated and corrected with experimental results by modal testing of the machine components in which the natural frequencies and the shape of vibration modes are analyzed. The analysis resulted in determination of the direction of the maximal compliance of a particular machine component.

A Performance Study of Controlled Impact Timing on Harmonics Reduction in Operational Modal Testing

2018 ◽  
Vol 141 (3) ◽  
Author(s):  
Hong Cheet Lim ◽  
Zhi Chao Ong ◽  
Zubaidah Ismail ◽  
Shin Yee Khoo
Keyword(s):  
Modal Analysis ◽  
Modal Testing ◽  
Mode Shapes ◽  
Performance Study ◽  
Modal Assurance Criterion ◽  
Structural Dynamic ◽  
Impact Device ◽  
Load Component ◽  
Phase Angles ◽  
The Impact

As an alternative to operational modal analysis and classical experimental modal analysis (EMA), a novel method was introduced previously, namely impact-synchronous modal analysis (ISMA). The effectiveness ISMA on rotor and structural dynamic systems has been proven in previous literature. More recently, an automated impact device (AID) was introduced which utilized tachometer pulse as initiation signal and its effectiveness on ISMA was proven. An attempt to further enhance this device in term of equipment and cost is then proposed by replacing the tachometer with the in-use tri-axial accelerometer through utilizing the filtered response of cyclic load component as an initiation signal to control the impact device, which is also the primary aim for this study. Prior to modal testing, accuracy of this device is illustrated at desired phase angles of 0 deg, 90 deg, 180 deg, and 270 deg. Subsequently, frequency response function (FRF) estimations obtained for ISMA using enhanced AID has demonstrated the suppression capabilities of this device on disturbances, i.e., reduction of 93.58% at 30 Hz and 57.78% at 60 Hz, resulting in a high correlation for signature assurance criterion (SAC) and cross signature assurance criterion (CSAC). Modal parameters extracted from the EMA and ISMA using impact device are presented and compared, for the first three natural modes of the test rig. It is found that natural frequencies are deviating by less than 6%, whereas modal assurance criterion (MAC) values between the mode shapes of the two tests are found to be above 0.9.

Ultrastructural changes in sciatic nerve tissue: Effects of passive maternal smoking

1983 ◽  
Vol 41 ◽  
pp. 650-651
Author(s):  
Amankwah K.S. ◽  
A.D. Weberg ◽  
R.C. Kaufmann
Keyword(s):  
Sciatic Nerve ◽  
Maternal Smoking ◽  
Ultrastructural Level ◽  
Uranyl Acetate ◽  
Nerve Tissue ◽  
Ultrastructural Changes ◽  
Cacodylate Buffer ◽  
And Control ◽  
Spontaneous Delivery

Previous research has revealed that passive (involuntary inhalation) tobacco smoking during gestation can have adverse effects upon the developing fetus. These prior investigations did not concentrate on changes in fetal morphology. This study was undertaken to delineate fetal neural abnormalities at the ultrastructural level in mice pups exposed in utero to passive maternal smoking.Pregnant study animals, housed in a special chamber, were subjected to cigarette smoke daily from conception until delivery. Blood tests for determination of carbon monoxide levels were run at 15-18 days gestation. Sciatic nerve tissue from experimental and control animals were obtained following spontaneous delivery and fixed in 2.5% gluteraldehyde in 0.1M cacodylate buffer pH 7.3. The samples were post-fixed in osmium ferrocyanide (1:1 mixture of 1.5% aqueous OSO4 and 2.5% K4 Fe(CN)6). Following dehydration, the tissues were infiltrated with and embedded in Spurr. Sections were stained with uranyl acetate and lead citrate.

Pengaruh Kepuasan Kerja terhadap Organizational Citizenship Behavior (OCB) Alumni Diklat Kepemimpinan Tingkat IV di Provinsi Banten

2020 ◽  
Vol 16 (1) ◽  
Author(s):  
Enong Rostiawati
Keyword(s):  
Job Satisfaction ◽  
Organizational Citizenship ◽  
Organizational Citizenship Behavior ◽  
Leadership Training ◽  
Survey Methods ◽  
Citizenship Behavior ◽  
Entire Study ◽  
Analysis Technique ◽  
Study Population

Abstract: Organizational Citizenship Behavior (OCB) is a variable that can be influenced by job satisfaction. This study aims to determine the effect of job satisfaction variables on Organizational Citizenship Behavior OCB alumni level IV leadership training in Banten Province. This research uses a quantitative approach through survey methods. Data analysis technique used is simple linear regression. The population in this study were 40 respondents and the sample used was 40 respondents. Determination of the sample using total sampling techniques or samples taken from the entire study population. The results of the analysis and interpretation of research data show that the value of the regulatory coefficient of influence on job satisfaction on Organizational Citizenship Behavior (OCB) alumni of leadership training level IV is 0.740 thus it can be concluded that job satisfaction has a direct positive effect on Organizational Citizenship Behavior alumni training, meaning that improvement of satisfaction in IV level leadership training is 0.740. work has an impact on improving Organizational Citizenship Behavior for training alumni, So Organizational Citizenship Behavior for training alumni can be achieved through job satisfaction.Keywords: Job satisfaction, Organizational Citizenship Behavior, Leadership Training Alumni Level IV

Application of EDS Technique for OSP Film Thickness Measurement

2006 ◽  
Author(s):  
Prong Kongsubto ◽  
Sirarat Kongwudthiti
Keyword(s):  
Thin Film ◽  
Quantitative Analysis ◽  
Joint Strength ◽  
Critical Factor ◽  
Thickness Measurement ◽  
Ic Manufacturing ◽  
And Control ◽  
Film Thickness Measurement ◽  
Non Destructive

Abstract Organic solderability preservatives (OSPs) pad is one of the pad finishing technologies where Cu pad is coated with a thin film of an organic material to protect Cu from oxidation during storage and many processes in IC manufacturing. Thickness of OSP film is a critical factor that we have to consider and control in order to achieve desirable joint strength. Until now, no non-destructive technique has been proposed to measure OSP thickness on substrate. This paper reports about the development of EDS technique for estimating OSP thickness, starting with determination of the EDS parameter followed by establishing the correlation between C/Cu ratio and OSP thickness and, finally, evaluating the accuracy of the EDS technique for OSP thickness measurement. EDS quantitative analysis was proved that it can be utilized for OSP thickness estimation.

DETERMINASI PEMBIAYAAN MUSYARAKAH

Equity ◽  
2015 ◽  
Vol 18 (1) ◽  
pp. 19
Author(s):  
Regi Oktaviyori ◽  
Praptiningsih Praptiningsih
Keyword(s):  
Significant Influence ◽  
Hypothesis Test ◽  
Third Parties ◽  
Analysis Technique ◽  
Sample Amount ◽  
Level Of Significance ◽  
Fund Return

This study aims to examine the determination of musyarakah financing in Bank Syariah Mandiri (BSM) period March 2008-December 2011. The data is obtainedbased on bank finance reporting that at publication. It is gained sample amount of 44 months. The analysis technique used here is multiple linier regression and hypothesis test using t-statistic and F-statistic with level of significance 5%. The result of this research is Third Parties Fund (DPK) and return gives significantly on musyarakah financing. The return on asset is not significant to musyarakah financing. By simultaneous, musyarakah financing give significant influence on the level of Third Parties Fund, return and return on asset.

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