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Development of Features for Early Detection of Defects and Assessment of Bridge Decks

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Structural Durability & Health Monitoring 2023年第4期17卷 257-281页

作者： Ahmed Silik Xiaodong Wang Chenyue Mei Xiaolei Jin Xudong Zhou Wei Zhou Congning Chen Weixing Hong Jiawei Li Mingjie Mao Yuhan Liu mohammad Noori Wael A.Altabey Nanjing Zhixing Information Technology Co. Ltd.NanjingChina Jiangsu Advance Transportation Institute NanjingChina Suzhou Highway Development Center SuzhouChina Guangdong Communications Group Co. Ltd.GuangzhouChina Department of Mechanical Engineering California Polytechnic State UniversitySan Luis ObispoCA93405USA School of Civil Engineering University of LeedsLeedsLS29JTUK Department of Civil Engineering Faculty of Engineering SciencesNyala UniversityNyala092Sudan Department of Mechanical Engineering Faculty of EngineeringAlexandria UniversityAlexandria21544Egypt

Damage detection is an important area with growing interest in mechanical and structural *** of the critical issues in damage detection is how to determine indices sensitive to the structural damage and insensitive to the surrounding environmental *** damage identification indices commonly focus on structural dynamic characteristics such as natural frequencies,mode shapes,and frequency *** study aimed at developing a technique based on energy Curvature Difference,power spectrum density,correlation-based index,load distribution factor,and neutral axis shift to assess the bridge deck *** addition to tracking energy and frequency over time using wavelet packet transform,in order to further demonstrate the feasibility and validity of the proposed technique for bridge condition assessment,experimental strain data measured from two stages of a bridge in the different intervals were *** comparative analysis results of the bridge in first and second stage show changes in the proposed feature *** is concluded,these changes in the values of the proposed features can be used to assess the bridge deck performance.

关键词： Structural health monitoring strain monitoring distribution factor wavelet packet transform

Sequence and Biostratigraphy of Lower Cenozoic Succession in the Kopet-Dagh Basin, NE of Iran

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Open Journal of Geology 2013年第3期3卷 240-249页

作者： Batool Rivandi mohammad Vahidinia Mehdi Nadjafi Assadolah Mahboubi Abbas Sadeghi Department of Geology Faculty of Science Ferdowsi University of Mashhad Mashhad Iran

The main purpose of this paper is the sequence stratigraphy and biostratigraphy of lower Tertiary sediments on the base of larger benthic foraminifera in northeast of Iran (Chehel-Kaman Formation). This formation mainly consists of Limestone, dolomite and interbeds of sand, shale and evaporate sediments. Petrographical studies indicate that these sediments may have been deposited on a shallow carbonate platform ramp and consist of 4 carbonate lithofacies (15 subfacies). These lithofacies may have been deposited in open marine, shoal, lagoon and tidal flat environmental conditions. Sequence stratigraphy analysis led to identification of 4 third-order depositional sequences, bounded by type 2 (within the top of the underlying Pestehleigh Formation) and type 1 sequence boundaries (paleosol). Interpreted sea level curve in this basin can be relatively correlated with global curves during Paleocene time and a with a sea-level fall occurred in the latest Paleocene, followed by a rise in the earliest Eocene. Biostratigraphy study led to the identification of 32 larger benthic Foraminifera genera. The Paleocene/Eocene boundary has been probably recorded as a thin red paleosol horizon (~10 - 15 cm).

关键词： Kopeh-Dagh Basin Paleogene Larger Benthic Foraminifer Sequence Stratigraphy

One-Pot Synthesis of Aldol Adduct Catalyzed by Immobilized Picolylamine on Zirconia

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Modern Research in Catalysis 2014年第1期3卷 1-5页

作者： mohammad Sadiq Razia M. Naveed Umar Gul Zamin Department of Chemistry University of Malakand Khyber Pakistan

Direct aldol reactions have been successfully performed using aromatic aldehyde and cyclic ketone in nonpolar solvent by using immobilized picolylamine on zirconia as a catalyst, in a double walled batch reactor. The prepared catalyst was characterized by SEM, XRD and FT-IR. FT-IR peaks reveal the presence of picolylamine on the surface of zirconia. The catalyst shows excellent catalytic activity in aldol reaction of cyclohexanone with benzaldehyde in cyclohexane giving 2-hydroxyphenylmethylcyclohexanone (55.7% yield) in 4 hr at 80?C. Furthermore, the catalyst is recoverable by simple filtration and could be used several times without significant loss in activity.

关键词： Immobilized Picolylamine on Zirconia Aldol Reaction Cyclohexanone Benzaldehyde

A Measure Theoretical Approach for Path Planning Problem of Nonlinear Control Systems

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Intelligent Control and Automation 2011年第2期2卷 144-151页

作者： Amin Jajarmi Hamidreza Ramezanpour mohammad Dehghan Nayyeri Ali Vahidian Kamyad 不详

This paper presents a new approach to find an approximate solution for the nonlinear path planning problem. In this approach, first by defining a new formulation in the calculus of variations, an optimal control problem, equivalent to the original problem, is obtained. Then, a metamorphosis is performed in the space of problem by defining an injection from the set of admissible trajectory-control pairs in this space into the space of positive Radon measures. Using properties of Radon measures, the problem is changed to a measure-theo- retical optimization problem. This problem is an infinite dimensional linear programming (LP), which is approximated by a finite dimensional LP. The solution of this LP is used to construct an approximate solution for the original path planning problem. Finally, a numerical example is included to verify the effectiveness of the proposed approach.

关键词： Path Planning Optimal Control Measure Theory Linear Programming

Application of the Alpha Shape Method to Visualize and Analyze Surgical Motion

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Surgical Science 2017年第11期8卷 464-480页

作者： mohammad R. Maddah Caroline G. L. Cao Department of Biomedical Industrial and Human Factors Engineering Wright State University Dayton OH USA

Simulators play an important role in training surgery residents to perform laparoscopy surgery. Some of these simulators have the capability to track tool motion to assess performance. However, most have not utilized the data to analyze trainee performance in a meaningful way. The alpha shape method can be used to construct a geometric surface based on motion data to enable visualization of the performance, while the surface derivative (surface/time to completion)—efficiency—can be used as a metric to evaluate complex surgical performance. The utility of the alpha shape method was demonstrated in a pick-and-place task, where the motion path of laparoscopic graspers was recorded by a position sensor, miniBIRD 500?. An alpha shape method was used to measure the surface area of the 3D points in space occupied by the tool tips during task performance. Results show that the surface derivative measure alone may be able to model the speed-accuracy tradeoff function, thereby simplifying the analysis and evaluation of complex motion in surgical performance.

关键词： Surface Alpha Shape Motion Visualization Performance Assessment

Antimicrobial and cytotoxic potential of seeds and flowers crude extracts of sunflower

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Grain & Oil Science and Technology 2019年第4期2卷 103-108页

作者： Nuzha Bint Mahdi Bin Ali Al-Shukaili mohammad Amzad Hossain College of Pharmacy and Nursing University of Nizwa

Oil-producing crops,including Helianthus annuus L.(***,Sunflower),have been used for the treatment of different human diseases since ancient *** study aims to determine the antimicrobial and cytotoxic potential of different polarities of seeds and flower extracts of locally grown *** by well-established *** achieve the objects,the plant extracts were prepared from both flowers and seeds powder samples individually with methanol solvent by using a Soxhlet extraction *** antimicrobial and cytotoxic potential of the flowers and seed extracts were determined by the in vitro diffusion and brine shrimp method(BSL).The results of the antimicrobial potential of both prepared flower and seed extracts of various polarities at different concentrations showed promising potential against the gram-positive and gram-negative bacterial strains,within the range of inhibition zone 0–20 *** the flower extracts,the highest potential was obtained in water extract and the lowest potential was in butanol extract followed by water>ethyl acetate>hexane>methanol>chloroform>butanol ***,from the seed extracts,the highest potential was obtained in water extract and the lowest potential was in the methanol extract followed by water>hexane>butanol>ethyl acetate>chloroform>methanol *** the other hand,the results of cytotoxicity among the flowers extracts against the brine shrimp method where the highest LC50 against brine shrimp nauplii were found to be 31.25μg/mL in water extract and the lowest LC50 was 1345.86μg/mL in chloroform extract followed by water>ethyl acetate>hexane>butanol>methanol>chloroform ***,different polarities of seed extracts,the highest LC50 against brine shrimp nauplii was shown to be 109.56μg/mL in butanol extract and the lowest LC50 was 1513.56μg/mL in ethyl acetate extract followed by butanol>hexane>water>methanol>chloroform>ethyl acetate *** conclusion,the results showed that both flowers and s

关键词： Helianthus annuus Sunflower Antimicrobial potential Cytotoxic potential Agar gel diffusion method BSL method

Ultrasound-Assisted Emulsification Dispersive Liquid-Liquid Microextraction Based on Solidification of Floating Organic Droplet for Separation of Trace Gold Prior to Flame Atomic Absorption Spectroscopy Determination

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American Journal of Analytical Chemistry 2011年第2期2卷 243-249页

作者： Sayed Zia mohammadi mohammad Ali Karimi Ali Shiebani Laleh Karimzadeh 不详

In the present work, a ultrasound-assisted emulsification dispersive liquid-liquid microextraction based on solidification of floating organic droplet method has been developed as a sample preparation method prior to flame atomic absorption spectrometry determination of trace amounts of gold in the standard, wastewater and river water samples. In the proposed method, 1-dodecanol and 5-(4-dimethylamino-benzylidene) were used as extraction solvent and chelating agent, respectively. Several factors that may be affected on the ex-traction process, such as type and volume of the extraction solvent, ionic strength, pH of the aqueous solu-tion, extraction temperature and extraction time were studied and optimized. Under the best experimental conditions, the calibration curve exhibited linearity over the range of 8.0 ng●mL-1- 3.0 μg●mL-1 with a correlation coefficient of 0.9978 and detection limit based on three times the standard deviation of the blank signal was 1.5 ng●mL-1. Eight replicate determinations of 0.2 and 1.0 μg●mL-1 of gold gave a mean absorbance of 0.051 and 0.253 with relative standard deviations of ±2.3% and ±1.5%, respectively. Finally, the developed method was successfully applied to the extraction and determination of gold ions in a silica ore, wastewater, river water and standard samples and satisfactory results were obtained.

关键词： Ultrasound-Assisted Emulsification Microextraction Solidification Floating Organic Droplet Preconcentration Gold Determination Silica Ore

Evaluation of Comparative Management of Expanded Program Immunization for Children in Iran and in the World

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Health 2014年第19期6卷 2697-2704页

作者： Fereshteh Farzianpour Kobra Bamdad Mehrabani Nayeb Fadaei Dehcheshmeh mohammad Azmal Department of Health Management and Economics School of Public Health Tehran University of Medical Sciences Tehran Iran Department of Immunology School of Medicine Tehran University of Medical Sciences Tehran Iran

Background: EPI is one of the most cost-effective public health interventions that have already been identified. Mass vaccination is one of the most effective public health strategies that lead to a dramatic reduction in the incidence of many infectious diseases. This is a descriptive study (eco-logical exploratory) where data about the status of routine immunization of children under 6 years in 6 selected countries in terms of the routine immunization programs in each country, the coverage and reported cases of vaccine-preventable diseases from 2006 to 2008 were collected assuming that each country is a representative of a Continent;data about the status of Iran were also collected and a comparative study was performed in the next step. It is worth mentioning that selecting these countries was according to health experts to consolidate the data. Collection tools are data of international (WHO and UNICEF) and national organizations of the above countries. In all countries surveyed, triple vaccine, vaccines of polio, hepatitis B, measles, rubella and mumps are part of the routine immunization program for children under the age of 6 years, with the explanation that in South Africa only measles vaccine is injected instead of measles, rubella and mumps vaccines. The coverage rate of the vaccine and other vaccines in Iran was the best compared to other countries. This represents the widespread activity of health care systems of the country in the field of vaccination and tireless efforts of healthcare workers and health centers.

关键词： Evaluation Comparative Management Program Immunization Children Iran World

Seasonal Variation in Volatile Oil, Polyphenol Content and Antioxidant Activity in Extract of Laurus nobilis Grown in Iran

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Journal of Pharmacy and Pharmacology 2015年第5期3卷 223-231页

作者： Atefeh Bahmanzadegan Vahid Rowshan Faraneh Zareian Reza Alizadeh mohammad Bahmanzadegan Department of Natural Resources Fars Research Center for Agriculture and Natural Resources Shiraz PO Box 71555-617 Iran Department of Chemistry Faculty of science Qom University Qom PO Box *** Iran Department of Mechanical engineer Faculty of science Jahrom University Jahrom PO Box 7413 766171 Iran

The leaves ofLaurus nobilis were collected in the middle of four seasons （spring, summer, autumn, and winter） to determine the best harvesting time for obtaining the highest oil yield, 1,8-cineole and polyphenol content and antioxidant activity. After drying the plant materials in shade, their EOs （essential oils） were obtained by hydro-distillation method. Analysis of variance showed harvesting time had significant effect on the oil yields of L. nobilis. Seventy one components were identified in the oils of L. nobilis with 1, 8-cineole （5.7%-42.6%）, ot-terpinyl acetate （3.2%-13.1%）, sabinene （2.3%-12.0%）, beta-elemene （0.2%-17.7%） and （E）-caryophyllene （0.2%-16.9%） as the main constituents in different seasons. The predominant phenolic constituents in L. nobilis were cinnamic acid, carvacrol, quercetin and coumarin, respectively. Gallic acid, catechin, caffeic acid, chloregenic acid, p-Comaric acid and rutin were not detected in any seasons. The best antioxidant activity was in spring （268.6μg/mL） and the lowest one was in winter （702.1μg/mL）.

关键词： Laurus nobilis EO seasonal variation polyphenol antioxidant.