Survival Analysis of Bridge Superstructures in Wisconsin

Although survival analyses have long been used in biomedical research, their application to engineering in general, and bridge engineering in particular, is a more recent phenomenon. In this research, survival (reliability) of bridge superstructures in Wisconsin was investigated using the Hypertabastic accelerated failure time model. The 2012 National Bridge Inventory (NBI) data for the State ofWisconsin were used for the analyses. A recorded NBI superstructure condition rating of 5 was chosen as the end of service life. The type of bridge superstructure, bridge age, maximum span length (MSL) and average daily traffic (ADT) were considered as possible risk factors in the survival of bridge superstructures. Results show that ADT and MSL can substantially affect the survival of bridge superstructures at various ages. The reliability of Wisconsin superstructures at the ages of 50 and 75 years is on the order of 63% and 18%, respectively, when the ADT and MSL values are at Wisconsin’s mean values

Conditional survival analysis for concrete bridge decks

Bridge decks are a significant factor in the deterioration of bridges, and substantially affect long-term bridge maintenance decisions. In this study, conditional survival (reliability) analysis techniques are applied to bridge decks to evaluate the age at the end of service life using the National Bridge Inventory records. As bridge decks age, the probability of survival and the expected service life would change. The additional knowledge gained from the fact that a bridge deck has already survived a specific number of years alters (increases) the original probability of survival at subsequent years based on the conditional probability theory. The conditional expected service life of a bridge deck can be estimated using the original and conditional survival functions. The effects of average daily traffic and deck surface area are considered in the survival calculations. Using Wisconsin data, relationships are provided to calculate the probability of survival of bridge decks as well as expected service life at various ages. The concept of survival dividend is presented and the age when rapid deterioration begins is defined

Survival Analyses for Bridge Decks in Northern United States

The use of deicing salts in northern regions of the United States is a major contributor to the long-term deterioration of bridge decks. In this study, the 2008 U.S. National Bridge Inventory (NBI) records were used to develop survival models for non-reconstructed bridge decks in six northern states of Minnesota, Wisconsin, Michigan, Ohio, Pennsylvania, and New York. The hypertabastic accelerated failure model was used to develop survival (reliability) and hazard (failure rate) functions for all six states. The NBI parameters included were the deck rating, type of superstructure (concrete or steel), deck surface area, age, and average daily traffic (ADT). A recorded NBI deck rating of 5 was considered to be the end of service life. Results show that ADT and deck surface area are both important factors affecting reliability and failure rates in all six states studied. In general, deck reliability and failure rates correspond reasonably well with qualitative measure of the harshness of each state’s winters. The type of superstructure has a varied influence in different states. It is recommended that deck area and ADT be considered as important factors when planning maintenance operations

Optimal power routing scheme between and within interlinking converters in unbalanced hybrid AC–DC microgrids

An optimal power routing (OPR) scheme between and within interlinking converters (ICs) in unbalanced hybrid AC–DC microgrids to minimise the power imbalance factor at the point of common coupling, active power losses, and voltage deviation indices for microgrids in grid-connected operating mode is proposed in this study. These goals are achieved through a multi-objective optimisation model by optimal distributing of mobile loads between available charging stations and at the same time, OPR within three phases of three-phase four-lag AC/DC converters. Numerical results obtained from implementing the proposed method on the modified IEEE 13-bus system, as an unbalanced hybrid microgrid, and IEEE 34-bus test system, as an unbalanced distribution system, demonstrate that proposed OPR algorithm is successful to satisfy the optimisation goals. For this purpose, four case studies are defined and studied to demonstrate the unique features of the proposed OPR comparing with other power routing schemes. In addition to simulation results, the OPR scheme between ICs is realistically implemented at Florida International University smart grid testbed to show the effect of the power routing on energy losses reduction

Perancangan Ulang Instalasi Pengolahan Air Limbah Domestik dengan Proses Anaerobic Baffled Reactor dan Anaerobic Filter

Instalasi Pengolahan Air Limbah (IPAL) Tarbiyatul Fallah merupakan IPAL domestik yang melayani Pesantren Tarbiyatul Fallah, namun berhenti beroperasi sejak tahun 2014. Agar manfaat IPAL dapat terus dirasakan, dilakukan perancangan ulang IPAL dengan alternatif Anaerobic Baffled Reactor (ABR) dan Anaerobic Filter (AF). Alternatif IPAL anaerobik yang keunggulan dalam kemudahan penerapan dan biaya operasional yang rendah. Perancangan ulang dimulai dengan mengevaluasi kinerja IPAL yang sudah ada. Hasil evaluasi digunakan untuk mengetahui permasalahan IPAL. Kemudian dilakukan perencanaan aternatif IPAL dengan proses ABR dan AF. Hasil perencanaan adalah berupa DED, BOQ, dan RAB pembangunan dan operasional. Berdasarkan hasil tersebut kemudian dibandingkan kelebihan dan kekurangan dari masing-masing alternatif IPAL. IPAL Tarbiyatul Fallah berhenti beroperasi disebabkan oleh permasalahan bau dan suara bising dari proses aerasi yang meresahkan masyarakat dan biaya operasional yang tinggi. Alternatif IPAL pengganti dapat berupa ABR dengan dimensi (15,1 m x 1,9 m x 2,3 m) dan AF dengan dimensi (13,75 m x 2,4 m x 2,3 m). Biaya pembangunan untuk ABR sebesar Rp152.969.500 dan AF sebesar Rp175.140.500. Sedangkan biaya operasional ABR sebesar Rp17.012.400 per tahun dan AF sebesar Rp21.345.950 per tahun. ABR memiliki keunggulan dalam hal tingkat penyisihan polutan, waktu tinggal, luas lahan dan biaya pembangunan dan operasional dibanding AF. Sedangkan AF memiliki keunggulan dalam jumlah kompartemen dan kebutuhan beton yang dibanding ABR

Kuwaiti EFL Students’ Perceptions of the Effectiveness of the Remedial English Course 099 at the College of Technological Studies

The study aims to evaluate the English remedial course 099 taught in the College of Technological Studies (PAAET) as part of the English program which disseminates English Language Skills to EFL students studying at this college. This study is expected to provide sufficient information to policymakers and educators involved with this program at all levels, with the intention to help them evaluate this course and make useful decisions to improve English Language Teaching in order to combat the deficiency in the English language suffered by college students in Kuwait. A number of 155 students participated in a questionnaire of 15 statements divided into four areas: reading, grammar, writing, and speaking skills. The findings of the study showed that most EFL students benefited from the English course 099, and their language skills were improved. However, there were some drawbacks and weaknesses of the program in terms of learners’ assessments and follow up. The significance of the study arises from the fact that it would enable decision-makers and course evaluators to pinpoint the strengths and weaknesses of the course and hence find ways to improve it

Detection of the recurrence of superficial urothelial carcinoma of urinary bladder by combined urine cytology and cystoscopy

The study was aimed to evaluate the accuracy of combined urine cytology and cystoscopy for the detection of the recurrence of superficial urothelial carcinoma of urinary bladder without bladder biopsy. A total 60 patients [males 48, females 12; age range 41-80 years (mean age- 63.15 years)] were included. Urine cytology as well as cystoscopy were done with a targeted biopsy taken from any apparently visible growth in the bladder. The systematic biopsy was taken where there was no growth. Reports of the cytology and cystoscopy were compared with the histopathology reports. It was found that 18 patients were cytology positive (false positive 2) and 42 patients were cytology negative (false negative 10) with sensitivity 61.5% and specificity 94%. During cystoscopy 24 patients were found recurrent growth in the bladder (false positive 3) and 36 patients were negative (false negative 5) with sensitivity 80.7% and specificity 91%. But when combined urine cytology and cystoscopic findings evaluated, the sensitivity and specificity were found 100% and 91% respectively. In conclusion, combined urine cytology and cystoscopy can be used for the detection of recurrence of superficial urothelial carcinoma of urinary bladder

Perovskite materials in X-ray detection and imaging: Recent progress, challenges, and future prospects

Perovskite materials have attracted significant attention as innovative and efficient X-ray detectors owing to their unique properties compared to traditional X-ray detectors. Herein, chronologically, we present an in-depth analysis of X-ray detection technologies employing organic-inorganic hybrids (OIHs), all-inorganic and lead-free perovskite material-based single crystals (SCs), thin/thick films and wafers. Particularly, this review systematically scrutinizes the advancement of the diverse synthesis methods, structural modifications, and device architectures exploited to enhance the radiation sensing performance. In addition, a critical analysis of the crucial factors affecting the performance of the devices is also provided. Our findings revealed that the improvement from single crystallization techniques dominated the film and wafer growth techniques. The probable reason for this is that SC-based devices display a lower trap density, higher resistivity, large carrier mobility and lifetime compared to film- and wafer-based devices. Ultimately, devices with SCs showed outstanding sensitivity and the lowest detectable dose rate (LDDR). These results are superior to some traditional X-ray detectors such as amorphous selenium and CZT. In addition, the limited performance of film-based devices is attributed to the defect formation in the bulk film, surfaces, and grain boundaries. However, wafer-based devices showed the worst performance because of the formation of voids, which impede the movement of charge carriers. We also observed that by performing structural modification, various research groups achieved high-performance devices together with stability. Finally, by fusing the findings from diverse research works, we provide a valuable resource for researchers in the field of X-ray detection, imaging and materials science. Ultimately, this review will serve as a roadmap for directing the difficulties associated with perovskite materials in X-ray detection and imaging, proposing insights into the recent status, challenges, and promising directions for future research

Determination of HCV genotypes and viral loads in chronic HCV infected patients of Hazara Pakistan

Hepatitis C Virus (HCV) genotype and viral load are two significant predictive variables knowledge of which might persuade treatment decisions. The objective of the present study was to identify the distribution of different HCV genotypes circulating in the study area and to estimate viral load in chronically HCV infected patients. Out of total 305 HCV positive patients, 177 (58%) were males and 128 (42%) were females. Frequency breakup of the HCV positive patients was 169, 69, 38 and 29 from Abbottabad, Mansehra, Haripur and Battagram districts respectively. Out of the total 305 tested serum samples, 255 (83.06%) were successfully genotyped whereas 50 (16.4%) samples were found with unclassified genotypes. Among typable genotypes, 1a accounted for 21 (6.8%) 1b for 14 (4.6%), 2a for 4 (1.31%) 3a for 166 (54.42%) and genotype 3b for (8.19%). Twenty five (8.19%) patients were infected with mixed HCV genotypes. Viral load distribution was classified into three categories based on its viral load levels such as low (< 60, 0000 IU/mL), intermediate (60,0000-80,0000 IU/mL) and high (> 80,0000 IU/mL). The baseline HCV RNA Viral load in HCV genotype 3 infected patients was 50 (26.17%), 46 (24.08%) and 95 (49.73%) for low, intermediate and high categories respectively. For genotypes other than 3, these values for low, intermediate and high viral load categories were 50 (43.85), 35 (30.70) and 29 (25.43) respectively. Pre-treatment viral load in patients with untypable genotype was 19 (38.00%), 5 (20.00%) and 11 (44.00%) for low, intermediate and high viral load categories. Viral load distribution was also categorized sex wise; for males it was 58 (32.76%), 26 (14.68%) and 93 (52.54%) whereas for females it was 40 (31.25%), 34 (26.56%) and 54 (42.18%) for low, intermediate and high viral load respectively. In conclusion HCV genotype 3a is the most prevalent genotype circulating in Hazara Division like other parts of pakistan. Pre-treatment viral load is significantly high (p 0.014) in patients infected with HCV genotype 3 as compared to other genotypes

The relationship between modified Graeb score and intraventricular hematoma volume with Glasgow outcome scale and modified Rankin scale in intraventricular hemorrhage of brain: a comparative study

Background: Intraventricular hemorrhage (IVH) is an acute neurosurgical condition. The aim of this study was to identify the relationship between modified Graeb score (mGS) and intraventricular hematoma volume with Glasgow outcome scale (GOS) and modified Rankin scale (mRS).Methods: This is a Quasi-experimental study conducted in the department of neurosurgery, Chittagong Medical College Hospital, Chittagong, Bangladesh during the period from 24 July 2018 to 23 July 2019. After a detailed history and clinical examination, 150 patients were selected for this study. The study participants were divided into two major groups- external ventricular drainage (EVD) and conservative; both groups consisted of 44 patients. Written informed consent were taken from the participants. Data were analyzed using statistical package for the social sciences (SPSS) software.Results: Overall mean age was around 60 years with an age range from 15-85 years. More than three fourth of the patients in both groups were from the age group of >50 years (73.83%). There were no differences between EVD and conservative groups regarding medical comorbidities. Most prevalent comorbidity among the patients of both groups’ hypertension, followed by diabetes and previous ischemic stroke. Overall the most frequent symptoms in the studied patients were vomiting, followed by loss of consciousness, headache and convulsion. There were no significant differences between the two groups regarding presenting symptoms. The mean Glasgow coma scale (GCS) score level was significantly lower in the patients with EVD than their counterpart from 1st post-operative day to 8th post-operative day. However, within-group comparison shows that the GCS score was significantly increased from 1st day to 8th day in both groups of patients.Conclusions: These findings can be used to identify patients in whom an EVD may provide measurable outcomes benefit with respect to patient mortality and help guide neurosurgical decision-making in particular patient subgroups with acute IVH