Development of Imaging Technique for Evaluating the RC Plate Containing Epoxy-Repaired Delamination

2006 ◽  
Vol 321-323 ◽  
pp. 348-351 ◽  
Author(s):  
Chia Chi Cheng ◽  
Kuang Chih Pei ◽  
Jiunn Hong Wu
Keyword(s):  
Transfer Functions ◽  
Imaging Technique ◽  
Crack Depth ◽  
Spectral Image ◽  
Impact Echo ◽  
Amplitude Spectra ◽  
Before And After ◽  
Force Time ◽  
The Impact ◽  
Crack Widths

The paper introduces a newly developed imaging technique for evaluating the integrity of concrete structures. The image of normalized amplitude spectra is obtained from B-scan of impact-echo tests. The normalizing process was carried out by obtaining the simulated transfer functions, in which the displacement of R-wave waveform of the impact-echo response multiplying a correcting factor is used as the simulated force-time function. Two specimens, one reinforced and the other unreinforced concrete plates, containing naturally delaminated cracks with crack widths 1 mm, 3 mm and 5 mm were constructed and repaired by injected epoxy into the delaminated cracks. The NDT method was performed on the specimens before and after the repairing work for comparison. The spectral image shows consistent high intensity at the crack-depth-frequency for specimens at crack stages and less in intensity for the ones at repaired stage.

Determination of impact events on a plate-like composite structure

2016 ◽  
Vol 120 (1228) ◽  
pp. 984-1004 ◽  
Author(s):  
L. Xu ◽  
Y. Wang ◽  
Y. Cai ◽  
Z. Wu ◽  
W. Peng
Keyword(s):  
Composite Structures ◽  
Transfer Functions ◽  
Flat Glass ◽  
Time History ◽  
Identification Algorithm ◽  
Impact Location ◽  
Force Time ◽  
The Impact ◽  
The Relationship ◽  
Impact Events

ABSTRACTComposite materials have been increasingly used in aircraft structures. However, these composite structures are susceptible to damage from external low-velocity impacts. In this paper, an impact identification algorithm is proposed to estimate the impact location and force time history simultaneously. A localisation method based on basis vectors is proposed, and the impact force time history is reconstructed by simplified transfer functions. The basis vector stands for the relationship between the impact location and the sensor signals, and the transfer function shows the relationship of the sensor signal and the force time history. An experiment is conducted on a flat glass fibre-epoxy matrix composite plate to verify the developed algorithm using only four sensors. The soft impactor and hard impactor are two typical impactors for impact events; therefore, the impact experiment is performed by the rubber and the steel impactors, respectively. The experimental results indicate that the proposed algorithm is feasible for the identification of impact events on plate-like composite structures.

Calibration of an Impact Device and Its Application to the Normalized Spectral Analysis of Impact-Echo Tests

2006 ◽  
Vol 321-323 ◽  
pp. 381-385 ◽  
Author(s):  
Yi Ching Lin ◽  
Chun Kuei Yang ◽  
Chia Chi Cheng
Keyword(s):  
Acoustic Impedance ◽  
Dissimilar Materials ◽  
Piezoelectric Sensor ◽  
Calibration Method ◽  
Steel Sphere ◽  
Impact Echo ◽  
Impact Device ◽  
The Difference ◽  
Force Time ◽  
The Impact

The objective of this paper is to introduce an impact device made by embedding a piezoelectric sensor into a steel sphere and to develop a calibration method for measuring the impact force. The force-time function of impact can be used to normalize the spectrum obtained from an impact-echo test. Furthermore, an approach was proposed to make the normalized spectrum dimensionless. A new technique based on the dimensionless normalized spectrum is developed to quantitatively evaluate the difference in acoustic impedance at the interface between two dissimilar materials. The impact-echo test results show that the dimensionless normalized spectrum is capable of identifying the degree of the difference in acoustic impedance at the interface between two dissimilar materials.

Atomic resolution characterisation of interface structures by Electron Energy Loss Spectroscopy

1993 ◽  
Vol 51 ◽  
pp. 576-577
Author(s):  
N. D. Browning ◽  
M. M. McGibbon ◽  
M. F. Chisholm ◽  
S. J. Pennycook
Keyword(s):  
High Resolution ◽  
Energy Loss ◽  
Electron Energy ◽  
Electron Energy Loss Spectroscopy ◽  
Imaging Technique ◽  
Atomic Scale ◽  
Atomic Resolution ◽  
Reference Image ◽  
The Impact ◽  
Electron Energy Loss

The recent development of the Z-contrast imaging technique for the VG HB501 UX dedicated STEM, has added a high-resolution imaging facility to a microscope used mainly for microanalysis. This imaging technique not only provides a high-resolution reference image, but as it can be performed simultaneously with electron energy loss spectroscopy (EELS), can be used to position the electron probe at the atomic scale. The spatial resolution of both the image and the energy loss spectrum can be identical, and in principle limited only by the 2.2 Å probe size of the microscope. There now exists, therefore, the possibility to perform chemical analysis of materials on the scale of single atomic columns or planes.In order to achieve atomic resolution energy loss spectroscopy, the range over which a fast electron can cause a particular excitation event, must be less than the interatomic spacing. This range is described classically by the impact parameter, b, which ranges from ~10 Å for the low loss region of the spectrum to <1Å for the core losses.

Strategic Role of Zakat in Multidimensional Quality of Life in Sijunjung, Indonesia

2018 ◽  
Vol 15 (1) ◽  
pp. 55-72
Author(s):  
Herlin Hamimi ◽  
Abdul Ghafar Ismail ◽  
Muhammad Hasbi Zaenal
Keyword(s):  
Quality Of Life ◽  
Positive Impact ◽  
Wealth Distribution ◽  
Absolute Poverty ◽  
Before And After ◽  
The Status ◽  
Being There ◽  
The Impact

Zakat is one of the five pillars of Islam which has a function of faith, social and economic functions. Muslims who can pay zakat are required to give at least 2.5 per cent of their wealth. The problem of poverty prevalent in disadvantaged regions because of the difficulty of access to information and communication led to a gap that is so high in wealth and resources. The instrument of zakat provides a paradigm in the achievement of equitable wealth distribution and healthy circulation. Zakat potentially offers a better life and improves the quality of human being. There is a human quality improvement not only in economic terms but also in spiritual terms such as improving religiousity. This study aims to examine the role of zakat to alleviate humanitarian issues in disadvantaged regions such as Sijunjung, one of zakat beneficiaries and impoverished areas in Indonesia. The researcher attempted a Cibest method to capture the impact of zakat beneficiaries before and after becoming a member of Zakat Community Development (ZCD) Program in material and spiritual value. The overall analysis shows that zakat has a positive impact on disadvantaged regions development and enhance the quality of life of the community. There is an improvement in the average of mustahik household incomes after becoming a member of ZCD Program. Cibest model demonstrates that material, spiritual, and absolute poverty index decreased by 10, 5, and 6 per cent. Meanwhile, the welfare index is increased by 21 per cent. These findings have significant implications for developing the quality of life in disadvantaged regions in Sijunjung. Therefore, zakat is one of the instruments to change the status of disadvantaged areas to be equivalent to other areas.

ANALISIS PENGARUH PEMBANGUNAN JALAN LAYANG JANTI TERHADAP PERKEMBANGAN TATA RUANG KAWASAN JANTI STUDI KASUS : KAWASAN JANTI, DESA CATURTUNGGAL, KABUPATEN SLEMAN, D. I. YOGYAKARTA

2017 ◽  
Vol 11 (3) ◽  
pp. 255
Author(s):  
Jeky El Boru
Keyword(s):  
Road Network ◽  
Open Space ◽  
Qualitative Description ◽  
Analysis Method ◽  
Open Spaces ◽  
The Road ◽  
Before And After ◽  
Linkage Method ◽  
The Impact ◽  
Parking Place

Abstract: This research aims to analyze the impact of Janti Flyover Construction toward the growth of layout at Janti Urban Area, including structured space, open space, and linkage. Method used for data collecting are observation, air photograph monitoring, and interview, whereas the analysis method is qualitative description, which is the superimposed method of two layers, that are the layout condition before and after flyover construction. The result shows that the impact of Janti Flyover construction can be seen on building mass (solid), the increasing number of open spaces, including the road network, parking place, and park, whereas the relation between spaces, visually and structurally, can be seen on the growth of buildings which have new shapes and styles, therefore the performance of the overall building does not have a proportional shape. Considering Janti Street at the collective relation, its role is getting stronger as the main frame road network.Keywords: Flyover construction, layout changing, Janti AreaAbstrak: Penelitian ini bertujuan untuk menganalisis pengaruh pembangunan Jalan Layang Janti terhadap perkembangan tata ruang Kawasan Janti, meliputi ruang terbangun, ruang terbuka, serta hubungan antar ruang (“linkage”). Metode pengumpulan data dilakukan melalui observasi, pengamatan foto udara, dan wawancara; sedangkan metode analisis melalui deskripsi secara kualitatif yang berupa “superimposed method” dari dua lapisan kondisi lahan, yakni kondisi tata ruang sebelum dan sesudah pembangunan jalan layang. Hasil penelitian menunjukkan bahwa pengaruh pembangunan Jalan Layang Janti terdapat pada massa bangunan (“solid”), pertambahan ruang terbuka yang berupa jaringan jalan, parkir, dan taman; sedangkan pada hubungan antar ruang ̶ secara visual dan struktural ̶ yakni tumbuhnya bangunan dengan bentuk dan gaya baru, sehingga bentuk tampilan bangunan secara keseluruhan tidak proporsional. Pada hubungan kolektif, Jalan Janti semakin kuat perannya sebagai kerangka utama jaringan jalan.Kata kunci : Pembangunan jalan layang, tata ruang, Kawasan Janti

Impact of merger on efficiency and productivity : a case study of commercial banks in Malaysia

1970 ◽  
Vol 5 (1) ◽  
pp. 77
Author(s):  
Mahadzir Ismail ◽  
Saliza Sulaiman ◽  
Hasni Abdul Rahim ◽  
Nordiana Nordin
Keyword(s):  
Efficiency Score ◽  
Malmquist Productivity Index ◽  
Productivity Index ◽  
Data Envelopment ◽  
Master Plan ◽  
Before And After ◽  
Domestic Banks ◽  
The Impact ◽  
Efficiency And Productivity

The Financial Master Plan (2001- 2010) aims to enhance the capacity of banking industry so that higher effic iency and productivity can be reaped in the future. This study seeks to determine the impact of merger on the efficiency and productivity ofcommercial banks in Malaysia for the period 1995 until 2005. The study uses a non-parametric approach, nam ely DEA (data envelopment analysis?) to estimate the efficiency scores and to construct the Malmquist productivity index. To enable this estimation, three bank inputs and outputs are used. Amongst the findings are those banks exhibit higher efficiency score after the merger and thefo reign banks are more efficient than the local banks. Productivity of the banks is calculated in both periods, before and after the merger: The results show that, it is the local banks that have improved the most after the merger. The main source of productivity is technical change or innovation. The findings support the existing policy of having larger domestic banks in term of size.

THE EFFECT OF METACOGNITIVE INSTRUCTION ON MAXIMIZING EFL LEARNERS’ METACOGNITIVE AWARENESS IN LISTENING

2018 ◽  
Vol 7 (1) ◽  
pp. 8-17
Author(s):  
Mahsa Assadi
Keyword(s):  
Experimental Research ◽  
Listening Comprehension ◽  
Intervention Program ◽  
Metacognitive Awareness ◽  
Listening Test ◽  
Efl Learners ◽  
Metacognitive Instruction ◽  
Before And After ◽  
Comprehension Ability ◽  
The Impact

This study reports a pre-experimental research on the impact of metacognitive instruction on EFL learners’ metacognitive awareness and their listening performance. To obtain the goal of the study, a group of 30 Iranian intermediate EFL learners, including 14 males and 16 females, were selected randomly. Their ages range from 20 to 24. The participants took part in 16 weeks’ intervention program based on metacognitive pedagogical sequence consisted of five stages. The metacognitive awareness listening questionnaire (MALQ), and a listening test were also used to find changes in metacognitive awareness and listening performance before and after the treatment. The results of comparing pre and posttests scores revealed that metacognitive instruction raised the learners’ metacognitive awareness and helped them improve their listening comprehension ability.

Impact of Michigan’s new opioid prescribing laws on spine surgery patients: analysis of the Michigan Spine Surgery Improvement Collaborative

2020 ◽  
pp. 1-6
Author(s):  
Paul Park ◽  
Victor Chang ◽  
Hsueh-Han Yeh ◽  
Jason M. Schwalb ◽  
David R. Nerenz ◽  
...  
Keyword(s):  
Spine Surgery ◽  
Spinal Surgery ◽  
Readmission Rate ◽  
Rating Scale ◽  
Short Term ◽  
Readmission Rates ◽  
Opioid Prescribing ◽  
Number Of Patients ◽  
Before And After ◽  
The Impact

OBJECTIVEIn 2017, Michigan passed new legislation designed to reduce opioid abuse. This study evaluated the impact of these new restrictive laws on preoperative narcotic use, short-term outcomes, and readmission rates after spinal surgery.METHODSPatient data from 1 year before and 1 year after initiation of the new opioid laws (beginning July 1, 2018) were queried from the Michigan Spine Surgery Improvement Collaborative database. Before and after implementation of the major elements of the new laws, 12,325 and 11,988 patients, respectively, were treated.RESULTSPatients before and after passage of the opioid laws had generally similar demographic and surgical characteristics. Notably, after passage of the opioid laws, the number of patients taking daily narcotics preoperatively decreased from 3783 (48.7%) to 2698 (39.7%; p < 0.0001). Three months postoperatively, there were no differences in minimum clinically important difference (56.0% vs 58.0%, p = 0.1068), numeric rating scale (NRS) score of back pain (3.5 vs 3.4, p = 0.1156), NRS score of leg pain (2.7 vs 2.7, p = 0.3595), satisfaction (84.4% vs 84.7%, p = 0.6852), or 90-day readmission rate (5.8% vs 6.2%, p = 0.3202) between groups. Although there was no difference in readmission rates, pain as a reason for readmission was marginally more common (0.86% vs 1.22%, p = 0.0323).CONCLUSIONSThere was a meaningful decrease in preoperative narcotic use, but notably there was no apparent negative impact on postoperative recovery, patient satisfaction, or short-term outcomes after spinal surgery despite more restrictive opioid prescribing. Although the readmission rate did not significantly increase, pain as a reason for readmission was marginally more frequently observed.

Effects of use of an eHealth platform e-Vita for COPD patients on disease specific quality of life domains

2020 ◽  
Keyword(s):  
Quality Of Life ◽  
Functional State ◽  
Mental State ◽  
Self Management ◽  
Copd Patients ◽  
Before And After ◽  
Ehealth Intervention ◽  
The Impact ◽  
Disease Specific

Background: Integrated disease management with self-management for Chronic Obstructive Pulmonary Disease (COPD) is effective to improve clinical outcomes. eHealth can improve patients’ involvement to be able to accept and maintain a healthier lifestyle. Eventhough there is mixed evidence of the impact of eHealth on quality of life (QoL) in different settings. Aim: The primary aim of the e-Vita-COPD-study was to investigate the effect of use of eHealth patient platforms on disease specific QoL of COPD patients. Methods: We evaluated the impact of an eHealth platform on disease specific QoL measured with the clinical COPD questionnaire (CCQ), including subscales of symptoms, functional state and mental state. Interrupted time series (ITS) design was used to collect CCQ data at multiple time points. Multilevel linear regression modelling was used to compare trends in CCQ before and after the eHealth intervention. Results: Of 742 invited COPD patients, 244 signed informed consent. For the analyses, we only included patients who actually used the eHealth platform (n = 123). The decrease of CCQ-symptoms was 0,20% before the intervention and 0,27% after the intervention; this difference was statistically significant (P=0.027). The decrease of CCQ-mental was 0,97% before the intervention and after the intervention there was an increase of 0,017%; this difference was statistically significant (P=0,01). No significant difference was found in the slopes of CCQ (P=0,12) and CCQ-function (P=0,11) before and after the intervention. Conclusion: The e-Vita eHealth platform had a potential beneficial impact on the CCQ-symptoms of COPD patients, but not on functional state. The CCQ-mental state remained stable after the intervention, but this was a deterioration compared to the improving situation before the start of the eHealth platform. In conclusion, this study shows that after the introduction of the COPD platform, patients experienced fewer symptoms, but their mental state deteriorated slightly at the same time. Therefore, health care providers should be aware that, although symptoms improve, there might be a slight increase in anxiety and depression after introducing an eHealth intervention to support self-management.

Sign in / Sign up

Export Citation Format

Share Document