System Identification of a Building from Multiple Seismic Records

This paper describes the identification of finite dimensional, linear, time-invariant models of a 4-story building in the state space representation using multiple data sets of earthquake response. The building, instrumented with 31 accelerometers, is located on the University of California, Irvine campus. Multiple data sets, recorded during the 2005 Yucaipa, 2005 San Clemente, 2008 Chino Hills and 2009 Inglewood earthquakes, are used for identification and validation. Considering the response of the building as the output and the ground motion as the input, the state space models that represent the underlying dynamics of the building in the discrete-time domain corresponding to each data set are identified. The time-domain Eigensystem Realization Algorithm with the Observer/Kalman filter identification procedure are adopted in this paper, and the modal parameters of the identified models are consistently determined by constructing stabilization diagrams. The four state space models identified demonstrate that the response of the building is amplitude dependent with the response frequency and damping, being dependent on the magnitude of ground excitation. The practical application of this finding is that the consistency of this building response to future earthquakes can be quickly assessed, within the range of ground excitations considered (0.005g–0.074g), for consistency with prior response—this assessment of consistent response is discussed and demonstrated with reference to the four earthquake events considered in this study. Inclusion of data sets relating to future earthquakes will enable the findings to be extended to a wider range of ground excitation magnitudes

Variation of Modal Parameters of a Highway Bridge Extracted from Six Earthquake Records

Between 2005 and 2010 six earthquakes triggered a monitoring system consisting of 11 acceleration channels installed on the West Street On-Ramp, a three-span curved highway bridge located in the city of Anaheim, California. In this paper, three different system identification techniques are applied to the acceleration records to investigate and corroborate the dynamic properties of the bridge, that is, vibration frequencies, associated damping ratios and mode shapes. The identification techniques are applied to each one of the six seismic events. The identified frequencies and damping ratios are shown to be dependent variables of the earthquake intensity. In general, larger earthquake intensities result in reduced vibration frequencies and higher damping ratios of the bridge. Sensitivity analysis using a simple finite element model reveals that soil softening at the abutments considerably contributes to the variation in frequencies because of changes in the support conditions and ultimately in the global stiffness of the structure. In addition, mathematical models in the state space description are identified from the recorded response and excitation measurements. The state space models successfully replicate the bridge measured response to the earthquake from which it is constituted. The models also provide a reasonable prediction of the bridge response to a different earthquake

Phenotypic low-level isoniazid resistance as a marker to predict ethionamide resistance in mycobacterium tuberculosis

Background: Tuberculosis is one of the most prevalent diseases in Pakistan. Pakistan has the highest burden of MDR-TB in the Eastern Mediterranean region. Ethionamide is an anti-tuberculous drug frequently used to treat MDR-TB. Its drug susceptibility testing is not easily available in resource limited settings. Since it acts on the same target protein as isoniazid (inhA protein encoded by inhA gene), we sought to find out if phenotypic isoniazid resistance can be a marker of ethionamide resistance.Materials and Methods: This was a retrospective observational study conducted at the Aga Khan University hospital section of microbiology. Data was retrieved between 2011 to 2014 for all culture positive MTB strains. All culture positive MTB isolates with susceptibilities to isoniazid and ethionamide recorded were included in the study. Isoniazid and ethionamide susceptibilities were performed using agar proportion method on Middlebrook 7H10 agar. Rate of Ethionamide resistance between low-level isoniazid resistant, high level isoniazid resistant and isoniazid sensitive MTB was compared.Results: A total of 11,274 isolates were included in the study. A statistically significant association (P \u3c 0.001) was found between Ethionamide resistance and low-level isoniazid resistance (26.6%) as compared to high-level isoniazid resistance (8.85%) and isoniazid sensitivity (0.71%) in MTB strains. However this association was not seen in XDR-TB strains.Conclusion: Low level isoniazid resistance may be used as marker for phenotypic ethionamide resistance and hence guide clinicians\u27 choice of antituberculous agent for MDR-TB in Pakistan. Further studies involving detection of genotypic association of isoniazid and ethionamide susceptibilities are needed before a final conclusion can be derived

Theoretical Study of Solvent Effects on 1,3- Dipolar Cycloaddition Reaction

في هذه الدراسة تم اجراء التحليل الانحداري لثابت التفاعل 15 مع معاملات المذيبات لمجموعتين من تفاعلات الاضافة الحلقي ال1و3-ثنائي القطب. الاولى هي تفاعل الازوميثاين(1)  مع السايكلواوكتاين (2),و اليينامين(3), و ثنائي مثيل اسيتيلين كاربوكسيليت(4). والمجموعة الثانية هي تفاعل النيترونات 5و6 مع الدايبولاروفيل 7 . كما تم اجراء الحسابات الشبه تجريبية للمتفاعلات حيث رسمت القيم الكمية الناتجة ضد معاملات التفاعل وضد معاملات المذيبات. وتم الحصول على نتائج متباينة الجودة لهذه التفاعلات. واجري تحليل رج الانحداري لغرض تصحيح الشذوذ الخطي للنماذج ذات المعاملات المتعددة. الغرض من هذه الدراسة هو الحصول على نموذج او نماذج والتي بواسطتها يمكن التنبؤ بالظروف المثالية للتفاعل قبل العمل المختبري.In the present study the regression analysis of the rate constant k 15with solvent parameters, for two sets of 1,3-dipolarcycloaddition reactions were done. The first was the reaction azomethine 1 with cyclooctyne 2, ynamine 3 and dimethyl acetylenecarboxylate (4) in different nonprotic solvents. The second were the reactions of the nitrones 5 and 6 with dipolarophile 7. Semiempirical calculations (PM3) were done for the reactants. The resulting quantum descriptors HOMO-LUMO and the transition state quantum descriptors (LUMOdipolarophile - HOMOdipole (HdL) and LUMOdipole – HOMOdipolarophile (LdH)) were plotted against solvent parameters, in order to obtain predictive computational models. Good to excellent correlations were obtained for these reactions. The multiparameteric models obtained were corrected for collinearity   by using Ridge regression

Evaluation of structural properties of Baghdad-Baquba road pavements

Structural evaluation of the road pavements is an essential concept to ensure their efficiency to carry traffic loads and to archive the data for future usage especially in major highways. Baghdad-Baquba is an important interstate highway as it connects the capital of Iraq with Diyala governorate which is one of the biggest governorates in Iraq. In addition, this highway connects Baghdad city with several governorates in the north of Iraq. However, this highway exhibits low serviceability due to poor condition of its pavements. Therefore, the structure of the pavements must be evaluated to specify the causes those lead to the decrease in its serviceability and to propose the suitable rehabilitation methods. This study aims to adopt a field survey to extract a number of samples from selected section in this highway to evaluate the structural properties of the pavements based on laboratory testing. Four cores and one pit with 1×1 m dimensions were extracted from the pavements in the field. Several tests were implemented on these tests based on standard methods. The results of the tests were adopted to evaluate the capacity of the pavement based on AASHTO 1993 method. The results exhibited that the estimated applied traffic load exceeded the calculated allowable traffic load by more than 12 times which reflect the disastrous situation. Therefore, the study proposed to rehabilitate the pavements by reconstruction. The study proposed to construct three layers: asphaltic layer with thickness of 240 mm, granular base with thickness of 250 mm, and granular subbase with a thickness of 250 mm. The study stated that all layers must have superior quality with high elastic modulus to resist the predicated traffic load

Value Co-creation by Compulsory Facebook-Community in Corporate Culture: A Case Study Malaysian Logistic Company

The main purpose of this study was to investigate the value co-creation process using Facebook as compulsory by a company. A new value co-creation model was developed showing how Facebook could be successfully executed as a platform for the value co-creation process with the aim of providing the best possible service to the recipients. This research employed an explanatory case study due to its uniqueness, especially for sufficient and in-depth comprehension of the phenomenon. PKT Logistics Group Sdn Bhd (PKT) was chosen for this study due to its exceptional characteristic of declaring itself as ‘Facebook compulsory’ company in business after Facebook. Data were obtained from interviews, direct observations, and a questionnaire survey of the company’s top management, selected employees, and customers.The proposed model has successfully connected the company’s leader, employees, and customers with each other for attaining the ‘Ba’ in new knowledge creation spirally using Facebook as an effective platform. This has resulted in the achievement of a service-oriented value co-creation process.This research has contributed to create a new model of the value co-creation process involving all the stakeholders via a ‘Facebook community’, which could be useful for other service providers.This study differentiates itself from the restricted application of Facebook in business by focusing on Facebook as compulsory in a corporate culture. The new value co-creation process model thru a ‘Facebook community’ is original and might be first of this type study

CONSCIOUS USE OF CODE-SWITCHING TO IMPROVE FLUENCY IN SPOKEN ENGLISH OF BANGLADESHI STUDENTS

Purpose: Present-day English language teaching in Bangladesh, despite adopting Communicative Language Teaching (CLT), focuses more on accuracy (i.e. grammar) than fluency which is proved as a weak strategy. Fluency acquisition in speaking includes pronunciation, but focusing on pronunciation first, slows down the process of becoming a fluent speaker. Methodology: As code-switching exists at the tertiary level in Bangladesh and because of the tremendous fascination of Bangladeshi students towards Bengali, code-switching can be utilized as a tool to improve fluency in spoken English. Thus, this research proposes an alternative to existing approaches. Result: Once desired fluency is achieved; grammar and pronunciation will be emphasized respectively to attain proper speaking skills. The success of this process can be studied in three phases. In the first phase, it examines whether allowing code-switching while speaking English helps Bengali students achieve fluency or not. Applications: This research can be used for universities, teachers, and students. Novelty/Originality: In this research, the model of the Conscious Use of Code-Switching to Improve Fluency in Spoken English of Bangladeshi Students is presented in a comprehensive and complete manner