Elimination of environmental temperature effect from the variation of stay cable force based on simple temperature measurements

Chien-Chou Chen,Wen-Hwa Wu,Chun-Yan Liu,Gwolong Lai 국제구조공학회 2017 Smart Structures and Systems, An International Jou Vol.19 No.2

Under the interference of the temperature effect, the alternation of cable force due to damages of a cable-stayed bridge could be difficult to distinguish. Considering the convenience and applicability in engineering practice, simple air or cable temperature measurements are adopted in the current study for the exclusion of temperature effect from the variation of cable force. Using the data collected from Ai-Lan Bridge located in central Taiwan, this work applies the ensemble empirical mode decomposition to process the time histories of cable force, air temperature, and cable temperature. It is evidently observed that the cable force and both types of temperature can all be categorized as the daily variation, long-term variation, and high-frequency noise in the order of decreasing weight. Moreover, the correlation analysis conducted for the decomposed variations of all these three quantities undoubtedly indicates that the daily and long-term variations with different time shifts have to be distinguished for accurately evaluating the temperature effect on the variation of cable force. Finally, consistent results in reducing the range of cable force variation after the elimination of temperature effect confirm the validity and stability of the developed method.

Determination of stay cable force based on effective vibration length accurately estimated from multiple measurements

Chen, Chien-Chou,Wu, Wen-Hwa,Huang, Chin-Hui,Lai, Gwolong Techno-Press 2013 Smart Structures and Systems, An International Jou Vol.11 No.4

Due to its easy operation and wide applicability, the ambient vibration method is commonly adopted to determine the cable force by first identifying the cable frequencies from the vibration signals. With given vibration length and flexural rigidity, an analytical or empirical formula is then used with these cable frequencies to calculate the cable force. It is, however, usually difficult to decide the two required parameters, especially the vibration length due to uncertain boundary constraints. To tackle this problem, a new concept of combining the modal frequencies and mode shape ratios is fully explored in this study for developing an accurate method merely based on ambient vibration measurements. A simply supported beam model with an axial tension is adopted and the effective vibration length of cable is then independently determined based on the mode shape ratios identified from the synchronized measurements. With the effective vibration length obtained and the identified modal frequencies, the cable force and flexural rigidity can then be solved using simple linear regression techniques. The feasibility and accuracy of the proposed method is extensively verified with demonstrative numerical examples and actual applications to different cable-stayed bridges. Furthermore, several important issues in engineering practice such as the number of sensors and selection of modes are also thoroughly investigated.

Damage detection of a cable-stayed bridge based on the variation of stay cable forces eliminating environmental temperature effects

Chien-Chou Chen,Wen-Hwa Wu,Chun-Yan Liu,Gwolong Lai 국제구조공학회 2016 Smart Structures and Systems, An International Jou Vol.17 No.6

This study aims to establish an effective methodology for the detection of instant damages occurred in cable-stayed bridges with the measurements of cable vibration and structural temperatures. A transfer coefficient for the daily temperature variation and another for the long-term temperature variation are firstly determined to eliminate the environmental temperature effects from the cable force variation. Several thresholds corresponding to different levels of exceedance probability are then obtained to decide four upper criteria and four lower criteria for damage detection. With these criteria, the monitoring data for three stay cables of Ai-Lan Bridge are analyzed and compared to verify the proposed damage detection methodology. The simulated results to consider various damage scenarios unambiguously indicate that the damages with cable force changes larger than +-1.5% can be detected within 12 hours. Even though not exhaustively reflecting the environmental temperature effects on the cable force variation, both the effective temperature and the air temperature can be considered as valid indices to eliminate these effects at high and low monitoring costs.

Determination of stay cable force based on effective vibration length accurately estimated from multiple measurements

Chien-Chou Chen,Wen-Hwa Wu,Chin-Hui Huang,Gwolong Lai 국제구조공학회 2013 Smart Structures and Systems, An International Jou Vol.11 No.4

Due to its easy operation and wide applicability, the ambient vibration method is commonly adopted to determine the cable force by first identifying the cable frequencies from the vibration signals. With given vibration length and flexural rigidity, an analytical or empirical formula is then used with these cable frequencies to calculate the cable force. It is, however, usually difficult to decide the two required parameters, especially the vibration length due to uncertain boundary constraints. To tackle this problem, a new concept of combining the modal frequencies and mode shape ratios is fully explored in this study for developing an accurate method merely based on ambient vibration measurements. A simply supported beam model with an axial tension is adopted and the effective vibration length of cable is then independently determined based on the mode shape ratios identified from the synchronized measurements. With the effective vibration length obtained and the identified modal frequencies, the cable force and flexural rigidity can then be solved using simple linear regression techniques. The feasibility and accuracy of the proposed method is extensively verified with demonstrative numerical examples and actual applications to different cable-stayed bridges. Furthermore, several important issues in engineering practice such as the number of sensors and selection of modes are also thoroughly investigated.

Sulfuric Acid Hydrolysis and Detoxification of Red Alga Pterocladiella capillacea for Bioethanol Fermentation with Thermotolerant Yeast Kluyveromyces marxianus

( Chien Hui Wu ),( Wei Chen Chien ),( Han Kai Chou ),( Jung Woo Yang ),( Hong Ting Victor Lin ) 한국미생물 · 생명공학회 2014 Journal of microbiology and biotechnology Vol.24 No.9

One-step sulfuric acid saccharification of the red alga Pterocladiella capillacea was optimized, and various detoxification methods (neutralization, overliming, and electrodialysis) of the acid hydrolysate were evaluated for fermentation with the thermotolerant yeast Kluyveromyces marxianus. A proximate composition analysis indicated that P. capillacea was rich in carbohydrates. A significant galactose recovery of 81.1 ± 5% was also achieved under the conditions of a 12% (w/v) biomass load, 5% (v/v) sulfuric acid, 121°C, and hydrolysis for 30 min. Among the various detoxification methods, electrodialysis was identified as the most suitable for fermentable sugar recovery and organic acid removal (100% reduction of formic and levulinic acids), even though it failed to reduce the amount of the inhibitor 5-HMF. As a result, K. marxianus fermentation with the electrodialyzed acid hydrolysate of P. capillacea resulted in the best ethanol levels and fermentation efficiency.

Ecological risk assessment of a Cd contaminated soil landfill - a prelimanary evaluation based on toxicological infomation

Chien-Min Chen,Min-Chou Liu 환경독성보건학회 2004 한국독성학회 심포지움 및 학술발표회 Vol.- No.-

A Novel Esterase from Paenibacillus sp. PBS-2 Is a New Member of the β-Lactamase Belonging to the Family VIII Lipases/Esterases

( Chien Hui Wu ),( Wei Chen Chien ),( Kai Chou Han ),( Jung Woo Yang ),( Hong Ting Victor Lin ) 한국미생물 · 생명공학회 2014 Journal of microbiology and biotechnology Vol.24 No.9

Screening of a gene library from Paenibacillus sp. PBS-2 generated in Escherichia coli led to the identification of a clone with lipolytic activity. Sequence analysis showed an open reading frame encoding a polypeptide of 378 amino acid residues with a predicted molecular mass of 42 kDa. The esterase displayed 69% and 42% identity with the putative β-lactamases from Paenibacillus sp. JDR-2 and Clostridium sp. BNL1100, respectively. The esterase contained a Serx- x-Lys motif that is conserved among all β-lactamases found to date. The protein PBS-2 was produced in both soluble and insoluble forms when E. coli cells harboring the gene were cultured at 18°C. The enzyme is a serine protein and was active against p-nitrophenyl esters of C2, C4, C8, and C10. The optimum pH and temperature for enzyme activity were pH 9.0 and 30°C, respectively. Relative activity of 55% remained at up to 5°C with an activation energy of 5.84 kcal/mol, which indicates that the enzyme is cold-adapted. Enzyme activity was inhibited by Cd2+, Cu2+, and Hg2+ ions. As expected for a serine esterase, activity was inhibited by phenylmethylsulfonyl fluoride. The enzyme was remarkably active and stable in the presence of commercial detergents and organic solvents. This cold-adapted esterase has potential as a biocatalyst and detergent additive for use at low temperatures.

Diabetes risk in patients with chronic obstructive pulmonary disease: a retrospective cohort study

( Yi-chun Chou ),( Ta-liang Chen ),( Chien-chang Liao ) 대한결핵 및 호흡기학회 2019 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.127 No.-

Background: The relationship between chronic obstructive pulmonary disease (COPD) and diabetes remains incompletely understood. This study evaluated the risk of diabetes in COPD patients with and without exacerbations. Methods: We identified 4671 adults newly diagnosed with COPD exacerbations and 9342 adults newly diagnosed with COPD without exacerbations during 2000-2008 using Taiwan’s National Health Insurance Research Database. A comparison cohort of 18684 adults without COPD, matched by age and sex, was randomly selected from the same dataset for the control group. Diabetes events during 2000-2013 were ascertained from medical claims during the follow-up period. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of diabetes associated with COPD with or without exacerbations were calculated. Results: During the follow-up period, the incidences of diabetes for patients without COPD and for patients with COPD without or with exacerbations were 3.4, 4.1 and 7.4 per 1000 person-years, respectively (P < 0.0001). Increased risk of diabetes for patients with COPD without exacerbations (HR 1.09, 95% CI 1.02-1.17) and COPD with exacerbations (HR 2.18, 95% CI 1.88-2.52) was noted. The associaiton between COPD and diabetes risk was significant in various subgroups. Conclusion: Prevention and intervention strategies for diabetes risk is needed for this susceptible population.

A Systemic Review and Experts’ Consensus for Long-acting Injectable Antipsychotics in Bipolar Disorder

Yuan-Hwa Chou,Po-Chung Chu,Szu-Wei Wu,Jen-Chin Lee,Yi-Hsuan Lee,I-Wen Sun,Chen-Lin Chang,Chien-Liang Huang,I-Chao Liu,Chia-Fen Tsai,Yung-Chieh Yen 대한정신약물학회 2015 CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE Vol.13 No.2

Bipolar disorder (BD) is a major psychiatric disorder that is easily misdiagnosed. Patient adherence to a treatment regimen is of utmost importance for successful outcomes in BD. Several trials of antipsychotics suggested that depot antipsychotics, including long-acting first- and second-generation agents, are effective in preventing non-adherence, partial adherence, and in reducing relapse in BD. Various long-acting injectable (LAI) antipsychotics are available, including fluphenazine decanoate, haloperidol decanoate, olanzapine pamoate, risperidone microspheres, paliperidone palmitate, and aripiprazole monohydrate. Due to the increasing number of BD patients receiving LAI antipsychotics, treatment guidelines have been developed. However, the clinical applicability of LAI antipsychotics remains a global cause for concern, particularly in Asian countries. Expert physicians from Taiwan participated in a consensus meeting, which was held to review key areas based on both current literature and clinical practice. The purpose of this meeting was to generate a practical and implementable set of recommendations for LAI antipsychotic use to treat BD; target patient groups, dosage, administration, and adverse effects were considered. Experts recommended using LAI antipsychotics in patients with schizophrenia, rapid cycling BD, BD I, and bipolar-type schizoaffective disorder. LAI antipsychotic use was recommended in BD patients with the following characteristics: multiple episodes and low adherence; seldom yet serious episodes; low adherence potential per a physician’s clinical judgment; preference for injectable agents over oral agents; and multiple oral agent users still experiencing residual symptoms.

Outcomes after Admission of Liver Disease in Patients with Influenza Vaccination: A Nationwide Study

( Yi-chun Chou ),( Chien-chang Liao ),( Ta-liang Chen ) 대한간학회 2017 춘·추계 학술대회 (KASL) Vol.2017 No.1

Aims: The influences of influenza vaccination (IV) on outcomes of admission of liver disease are unclear. The purpose of this study is to investigate IV’s effects on pneumonia and mortality after liver disease in geriatric patients. Methods: Using Taiwan’s National Health Insurance Research Database reimbursement claims data from 2008 to 2013, we conducted a retrospective cohort study of 21385 patients aged more than 66 years who admitted to hospitalization due to liver disease (included viral hepatitis, cancer, necrosis of liver, and chronic liver disease) and 21035 had IV before the admission within one year. Multivariate logistic regressions were used to calculate adjusted odds ratios (ORs) and 95% confidence intervals (CIs) of post-admission pneumonia and in-hospital mortality associated with IV. Results: Patients receiving IV showed less pneumonia after liver disease (OR 0.51, 95% CI 0.35-0.75). But there was no significant association between IV and in-hospital mortality (OR 0.85, 95% CI 0.46-1.56) compared with unvaccinated patients. Conclusions: Vaccinated geriatric patients showed lower risks of pneumonia compared with unvaccinated patients undergoing similar admission of liver disease. Further studies are needed to explain how IV improves the outcomes of liver disease.