Search or add a thesis

Advanced Search (Beta)
Home > Inverse Identification of Constitutive Parameters of Carbon Fiber Reinforced Plastic Plates Using 2D Digital Image Correlation Techique

Inverse Identification of Constitutive Parameters of Carbon Fiber Reinforced Plastic Plates Using 2D Digital Image Correlation Techique

Thesis Info

Access Option

External Link

Author

Siddiqui, Muhammad Zeeshan

Program

PhD

Institute

National University of Sciences & Technology

City

Islamabad

Province

Islamabad

Country

Pakistan

Thesis Completing Year

2019

Thesis Completion Status

Completed

Subject

Mechanical Engineering

Language

English

Link

http://prr.hec.gov.pk/jspui/bitstream/123456789/12024/1/Muhammad%20Zeeshan%20Siddiqui%202019%20mechanical%20engg%20NUST%20isb%20prr.pdf

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676727781049

Asian Research Index Whatsapp Chanel
Asian Research Index Whatsapp Chanel

Join our Whatsapp Channel to get regular updates.

Similar


The mechanical, thermal as well as electrical properties of composite materials can be tailored to suite their use in specific applications. This adaptability has resulted in extensive use of these materials in manufacturing of industrial, aerospace, sports and household items. The role of accurate knowledge of the mechanical properties of these materials, in improving the product quality and reliability, offers strong motivation for research as it can bring down the product cost by improving design and manufacturing practices. Recent efforts towards the characterization of elastic response of the long fiber composites, or laminates, have seen a shift towards inverse identification techniques. The current research proposes application of a novel technique for inverse identification of the elastic moduli of transversely isotropic laminates. Two-dimensional Digital Image Correlation (2D-DIC) is used for full-field measurements which are required for the identification process. However, instead of the usual application of 2D-DIC for measurement of in-plane displacements, the pseudodisplacements resulting from out-of-plane (towards camera) deflection of plate under application of a point load are measured. These pseudo-displacements are basically the perspective projection of the three-dimensional displacement fields on the image-plane of the image acquisition system. The cost function in this method is defined in terms of these projections instead of the true displacements – and hence the name Projected Finite Element Update Method (PFEUM). The identification proceeds by iteratively minimizing the cost function by changing the material properties defined in the FE model. A sensitivity-based approach which predicts and explains the accuracy of material parameter identification for a composite plate using the PFEUM technique is also proposed. It is shown that the contribution of a specific material parameter in the observed displacement field influences the accuracy of its identification. The contributions from material parameters are first quantified in terms of sensitivity criterion which may be tailored by changing the elements of test configuration like location of supports, the load application point and the specimen geometry. Several test configurations are designed by maximizing the sensitivities corresponding to individual material parameters. The relevance of proposed sensitivity criterion in these configurations is then validated through material identification in simulated experiments with added Gaussian noise. Finally, a CFRP plate with 2mm thickness is tested under these configurations to demonstrate the practical use of this approach. The proposed approach helps in robust estimation of the inplane elastic moduli from a bent composite plate with a simple 2D-DIC setup without requiring measurement of the actual plate deflection or curvatures. The results are achieved with comparatively simple experimental setup and without application of the high-priced displacement measurement techniques thus resulting in cost savings.
Loading...
Loading...

Similar Books

Loading...

Similar Chapters

Loading...

Similar News

Loading...

Similar Articles

Loading...

Similar Article Headings

Loading...

بے کفن بستیوں میں

بے یقین بستیوں میں

                ناطق کو ادبی سفر کا آغاز کیے تھوڑا ہی عرصہ ہوا جب انہوں نے شاعری کی اس پہلی کتاب سے سب کی توجہ اپنی جانب مبذول کروالی۔یہ ان کا پہلا مجموعہ کلام ہے اس مجموعہ کلام میں انہوں نے کچھ ایسی نظمیں لکھی ہیں جن کو پڑھ کربعض اوقات انسان پر خوف طاری ہوجاتا ہے،ہر نظم میں ایک نادر بات ہے قاری متاثر ہوئے بغیر نہیں رہ سکتا۔ کتاب کی پہلی نظم کا عنوان ’’ریشم بننا کھیل نہیں‘‘اپنے آپ میں ایک بہت گہرائی میں لے جانے والا مطلب رکھتا ہے۔جیسے وہ کہہ رہے ہوں کہ شاعری کرنا آسان نہیں۔ان کی ایک نظم جس کاپہلا مصرع کچھ یوں ہے:

میں بانسوں کے جنگل میں ہوں جن کے نیزے بنتے ہیں

                نیزہ کی تعریف،مین اگر ہم سمجھیں تو بات سیدھی دل کو لگتی ہے یعنی بانسوں کو چھیل کر ہم نیزے بناتے ہیں۔بانسوں کے جنگل کو ناطق نے انسانوں سے تشبیہ دی ہے دنیا انسانوں کا جنگل ہے، جہاں طرح طرح کے لوگ رہتے ہیں۔یہ چاہیں تو بانس سے نیزہ بناڈالیں یا پھر قلم۔ایک اور مصرع جس میں وہ افسوس کرتے ہوئے نظر آتے ہیں جہاں ساری بات کھل کرسامنے آجاتی ہے اور واقعی احساس ہوتا ہے یہ دنیا کالے ناگوں سے بھری پڑی ہے جہاں ان ناگوں میں رہ کر اچھے لوگ اچھائی کا دم بھرنے والے بھی کالے ناگ بنتے جاتے ہیں بہت کم لوگ ہیں جو ان کالے ناگوں سے خود کوبچا پاتے ہیں۔

                ناطق کی نظم کا آخری مصرع بھی یہی ہے کہ’’لیکن جنگل بانسوں کاہے جن کے نیزے بنتے ہیں۔‘‘یہاں صرف ناگ رہتے ہیں اور ان ناگوں سے مصنف کو کوئی امید نہیں کہ وہ ان سے قلم بنائیں گے۔جب ان...

Employee Commitment and Culture Organization on Employee Performance

This study aims to analyze and examine the influence of employee commitment and cultural organizational factors towards employees of the Job Performance, Regional Secretariat (SetDa) Riau Province both simultaneously (overall test) and partial (individual test). The research method used is verification, while the population in this study is the Regional Secretariat (SetDa) Riau Province based on increasing totaling 402 people. By using the method of proportional stratified random sampling in the sample amount to obtain 40 respondents. While data collection technology is used by the field study and library that includes observation, interviews and question-naires, and to determine the relationship and the influence of an independent variable to the model variables to use Multiple Linear Regression Analysis. The results showed that the calculated results obtained statistically Multiple Correlation Coefficient (R) was 0.8950 with p <0.05 and the coefficient value of Determination (R2) 80.11%. This means that approximately 80.11% of employee commitment and organizational culture factors have a significant influence on employee job performance. Partial test showed that the partial coefficient of determination values contained in the organizational culture variables for (r2) = 54.58% with p = 0.00000 and tresult = 7.515> ttable = 1.678 and ttable variables for employee commitment (r2) = 78, 74% with p = 0.00000 and tresult = 13.196> ttable = 1.678. These results indicate that organizational cultural factors and employee commitment have a significant relationship influence on employee job performance of the Riau Province Regional Secretariat (SetDa).

Investigation of Antidiabetic Potential of Parthenium Hysterophorus Carrot Grass on Alloxan Induced Diabetic Rabbits

Parthenium hysterophorus is of great medicinal importance. It has been used to cure fever, malaria, diarrhea, dysentery, and neurologic disorders. It also has anticancer agents as well. This study evaluates the antidiabetic effects of methanolic extract of all plant parts of Parthenium hysterophorus in diabetic rabbits (alloxan-induced). Twenty-five rabbits were divided into 5 groups (N=5). The group I served as a standard control. Groups II to V were injected with freshly prepared alloxan solution 150mg/kg intraperitoneally to induce diabetes. Glucose levels were checked to ensure hyperglycemia (diabetes). Group II till V received these treatments. Group II: Alloxan 150mg/kg alone; group III: Alloxan + MEPH (50mg/kg); group IV: Alloxan +100mg/kg MEPH (100mg/kg); group V: Alloxan +Glucophage (62.5mg/kg) respectively for a period of 10 days orally via feeding cannula. The safety assessment of these extracts was carried out in rabbits by oral administration with 50mg/kg, 100mg/kg& 150mg/kg body weight daily for7 days. They remained normal at the dose of 50g/kg, 100g/kg whereas, they showed anxiety in their behavior at high dose i.e., 150mg/kg. Changes in the body weight of all animals were recorded on day 1 , 7 st th 4 th and 10 and 10 th days. Short term (1 st , 3 rd , 5 th and7 th hour) and long term (4 th , 7 th th day) hypoglycemic effect were recorded using easy glucometer C 20. All animals were sacrificed on 10 day to isolate the pancreas for histopathological examination. The results showed that Parthenium hysterophorus L. lowers the blood glucose level in all the groups of alloxan-induced diabetic rabbits. However, the swift reduction in blood glucose level with MEPH was comparatively less than the experimental standard drug i.e., Glucophage.The Pancreatic histopathological studies depicted that a high dose of MEPH administration repaired alloxan-induced pancreatic damage. Whereas, Glucophage only reduced blood glucose level as no repair in damaged tissue was observed in the histopathological study of Glucophage treated animals. The study shows that the whole plant of Parthenium hysterophorus L. is very useful for developing effective phytomedicine to treat diabetes mellitus. The present investigation recommends the use of Parthenium hysterophorus as an herbal remedy for diabetes