Performance-based seismic analysis and design improvements of two precast concrete structural systems

This study focuses on the multiple-level seismic performance in terms of structural and non-structural damages of precast hybrid frame and jointed precast post-tensioned wall systems through dynamic analysis of precast buildings subjected to spectrum compatible ground motions of various intensities. The maximum transient interstory drift, residual interstory drift and floor acceleration are considered as acceptance criteria for evaluating seismic performance of these systems subjected by four levels of ground motions. Interstory drift and floor acceleration are directly related to structural and non-structural damages, respectively. Two dimensional non-linear finite element analytical models for hybrid frames and jointed wall systems used in this study are validated against test results for a five story test building. In designing both precast systems, it is shown that traditional force-based design approach results in significantly higher level of design base shear compared to direct displacement-based design approach. After observing satisfactory performance in the five story model building designed by direct displacement-based approach, similar multiple-level seismic performance is evaluated for five, seven and ten story buildings designed by direct displacement-based method. These low to mid-rise full scale precast hybrid frame and jointed precast post-tensioned wall systems also exhibit the maximum transition interstory drift, residual interstory drift and floor acceleration within the acceptable limits, thus it is recommended that these systems may be utilized as primary lateral load resistant structural systems when designed by the economic approach of direct displacement-based design. Influence of variation of heights of buildings on the performance of these systems is also examined

Rethinking the I/O Stack for Persistent Memory

Modern operating systems have been designed around the hypotheses that (a) memory is both byte-addressable and volatile and (b) storage is block addressable and persistent. The arrival of new Persistent Memory (PM) technologies, has made these assumptions obsolete. Despite much of the recent work in this space, the need for consistently sharing PM data across multiple applications remains an urgent, unsolved problem. Furthermore, the availability of simple yet powerful operating system support remains elusive. In this dissertation, we propose and build The Region System – a high-performance operating system stack for PM that implements usable consistency and persistence for application data. The region system provides support for consistently mapping and sharing data resident in PM across user application address spaces. The region system creates a novel IPI based PMSYNC operation, which ensures atomic persistence of mapped pages across multiple address spaces. This allows applications to consume PM using the well understood and much desired memory like model with an easy-to-use interface. Next, we propose a metadata structure without any redundant metadata to reduce CPU cache flushes. The high-performance design minimizes the expensive PM ordering and durability operations by embracing a minimalistic approach to metadata construction and management. To strengthen the case for the region system, in this dissertation, we analyze different types of applications to identify their dependence on memory mapped data usage, and propose user level libraries LIBPM-R and LIBPMEMOBJ-R to support shared persistent containers. The user level libraries along with the region system demonstrate a comprehensive end-to-end software stack for consuming the PM devices

Profitability of green leaf cultivation in some selected areas of Panchagarh district in Bangladesh

The tea industry has the potentiality of the transform of socioeconomic conditions of rural Bangladesh which provides ample for self-employment of unemployed youth. The present study examines the socioeconomic characteristics, cultural practices and profitability of green leaf cultivation of the randomly selected 45 sample farmers from Panchagarh district in Bangladesh. Primary data were collected through field survey using an interview schedule. Some statistical measures like average percentage and ratios were calculated. The study showed that the average family size of the green leaf growers was 4.77. About 72 % of the respondents’ education levels were primary to higher secondary. On an average 100 % of the tea estates owners’ occupation was business while majority of smaller growers and small holder occupation was agriculture. The average size of land holding per family was 12.16 hectares. But on the other hand, area under tea cultivation was found to be 8.50 hectares. The number of bushes planted per hectare was 15218. The study showed that on average 71% farmers maintained the plant spacing (3 ft. x 2.5 ft.). It was found that 58% farmers plucked more than 3 leaves and bud. On an average, per kilogram cost of green leaf was Tk.11.60 ($0.137) and Tk. 13.15($ 0.155) on the basis variable and fixed cost, respectively. The cost was the highest in small holder while it was the lowest in the small farmer. The average per kilogram gross margin of green leaf was Tk.8.90 ($0.105). But on the other hand, per kilogram net benefit was Tk.7.35 ($ 0.087). The net benefit was the highest among the small farmer due to lower cost; while net benefit was the lowest in small holder due to higher cost of cultivation. The benefit cost ratio was 1.57

Quantitative analysis of Mouza map image to estimate land area using zooming and Canny edge detection

In Bangladesh, mouza map is used to maintain the record of land measurement, which is a form of interpreting land ownership as well as estimation. Unfortunately, the automatic determination of land is still under development. As a result, land administrators have to encounter multiple hurdles while evaluating any area by employing local civil engineers. Thus, our country needs an automated land estimation system so that it can reduce time, cost and other difficulties which inspired us to develop a system that requires only mouza map image. Once image acquisition is done, we applied the curvature interpolation techniqueto zoom the map that helps to select any area by the Area Selection Method. The selected area is then segmented by employing the Canny edge detection method. Finally, the area is calculated from the segmented image and extracted features of the selected location. Compared to the field measurement, the system gave the accuracy of 89.8%. Hence, the land administrators will be able to provide the land information to the landowners promptly

Role of women in pond fish farming and fish consumption situation in a selected area of Bangladesh

In Bangladesh, aquaculture makes an important contribution to rural livelihoods for food security, nutrition security and cash income. Small-scale fisheries typically depend on men and women’s roles. The Bangladesh fisheries sector is seen as a male domain and the contribution of women is poorly recognized. This study is concerned with the contribution of rural women in different activities of pond fish farming, profitability of pond fish culture, fish consumption level of the sample households and problems and constraints in pond fish farming. For achieving these objectives, 60 women pond fish farmers were selected randomly from Muktagacha upazila of Mymensingh district in Bangladesh. Primary data were collected personally from respondents through a sample survey with the help of a structured and pre-tested interview schedule. Both tabular and econometric techniques were used to analyze the collected data. The major findings indicated that a total working hour in a season (six months) was 418 of an average 12 decimal pond sizes. Men contribute 62.68% (262 hours) and women contribute 37.32% (156 hours) of the total working hours in a season. The per hector/season production, gross return, gross margin and net return were Kg.18188, Tk. 1655108, Tk.740736 and Tk. 654202, respectively. Undiscounted benefit-cost ratio was found 1.65 in the study area. Average per capita fish consumption was 69.01 gm/day, which was higher than the nation average of 44.65 gm/person/day. The main problems faced by the respondents were high feed cost, disease, high labour demand, high cost of a pond excavation, etc. This research concludes that women play a significant role in pond fish farming and achieving household nutrition security. The government and policy makers should acknowledge the women’s contribution in different farming activities and make appropriate policy for women entrepreneurship development in Bangladesh which will lead to achieve sustainable development goals

Rainwater harvesting at place of worship : a case study in Australia

There are several ways of preserving water covering technical, legal and cultural aspects. More recently, Rainwater Harvesting (RWH) has become one of the popular means of water-saving. A few studies on RWH system at place of worship have been undertaken; however, there has not been any detailed study in Australia. This research aims to explore how Islamic scripture can be used to promote water conservation among the Muslim community, specifically, this examines the feasibility of a RWH system at St Marys Islamic Centre, New South Wales, Australia where a RWH system is proposed to supplement mains water for regular uses such as washing, gardening, and socio-religious functions. Based on local daily rainfall data, a water balance model has been developed to estimate reliability of a RWH system at the proposed location. The preliminary result shows that for a 10 kL tank size, the average reliability of the proposed RWH system is 69% for 400 people. However, if the tank size increases, reliability also increases and therefore, higher tank size is needed at the proposed site. Finally, this result will be useful to understand the effects of Islamic motivation and RWH on water preservation. It is also expected that the outcomes of this research will promote water conservation in places of worship and community centres across Australia and other countries

BN-DRISHTI: Bangla Document Recognition through Instance-level Segmentation of Handwritten Text Images

Handwriting recognition remains challenging for some of the most spoken languages, like Bangla, due to the complexity of line and word segmentation brought by the curvilinear nature of writing and lack of quality datasets. This paper solves the segmentation problem by introducing a state-of-the-art method (BN-DRISHTI) that combines a deep learning-based object detection framework (YOLO) with Hough and Affine transformation for skew correction. However, training deep learning models requires a massive amount of data. Thus, we also present an extended version of the BN-HTRd dataset comprising 786 full-page handwritten Bangla document images, line and word-level annotation for segmentation, and corresponding ground truths for word recognition. Evaluation on the test portion of our dataset resulted in an F-score of 99.97% for line and 98% for word segmentation. For comparative analysis, we used three external Bangla handwritten datasets, namely BanglaWriting, WBSUBNdb_text, and ICDAR 2013, where our system outperformed by a significant margin, further justifying the performance of our approach on completely unseen samples.Comment: Will be published under the Springer Springer Lecture Notes in Computer Science (LNCS) series, as part of ICDAR WML 202

Vegetated roofs as a means of sustainable urban development : a scoping review

Urbanisation affects the water cycle and heat balance in a negative way. Vegetated roofs have the potential to minimise the effects of urbanisation. A scoping review is presented here to examine how vegetated roofs are being evolved as an effective tool of sustainable urban stormwater management and overall urban development. It has been found that research on vegetated roofs has been increasing significantly and it can contribute towards achieving multiple sustainable de-velopment goals (SDGs). It has also been found that the uptake of vegetated roofs has been slow. A lack of regulatory acceptance caused by an absence of experimental data and a subsequent knowledge gap establishing the effectiveness of vegetated roofs are major reasons behind this slow uptake. Future research on vegetated roofs and their subsequent evolutions should put a focus on gathering experimental data towards establishing a performance benchmark for detention, retention and water quality in urban settings. Such data can be utilised towards developing a stand-alone guideline and software for green roof design

Natural peste des petits ruminants virus infection in Black Bengal goats: virological, pathological and immunohistochemical investigation

BACKGROUND: Peste des Petits Ruminants (PPR), also known as Goat Plague, occurs in goats, sheep and related species. It is caused by a morbillivirus in the family Paramyxoviridae. In Bangladesh PPR is endemic and it causes serious economic losses. Pathology of PPR has been reported in different goat and sheep breeds from natural and experimental infections. Field results are better indicators of pathogenicity of the circulating virus. The severity of the disease varies with species, breed and immune status of the host. Pathological investigations of natural outbreaks of PPR in Balck Bengal goats are very limited. The current investigation was aimed at describing pathology and antigen localization in natural PPR infections in Black Bengal goats. RESULTS: A total of 28 outbreaks were investigated clinically and virologically. Average flock morbidity and mortality were 75% and 59%, respectively, with case fatality rate of 74%. Necropsy was conducted on 21 goats from 15 outbreaks. The major gross lesions were congestion of gastrointestinal tract, pneumonia, engorged spleen, and oedematous lymphnodes. Histopathological examination revealed severe enteritis with denudation of intestinal epithelium, severe broncho-interstitial pneumonia with macrophages within lung alveoli and extensive haemorrhages with depletion of lymphoid cells and infiltration of macrophages in the sinuses of spleen. In lymph nodes, the cortical nodules were replaced by wide sinusoids with severe depletion of lymphocytes, infiltration of mononuclear cells and some giant cells in sub-capsular areas and medullary sinuses. PPR virus antigen was found in pneumocytes and alveolar macrophages in lungs. Viral RNA could be detected by RT-PCR in 69 out of 84 nasal swab, 59 out of 84 blood and 21 out of 21 lymph node samples. Sequence analyses revealed closeness of Bangladeshi strains with other recent Asian isolates. CONCLUSION: Natural outbreaks of PPR in Black Bengal goats in Bangladesh resulted in 75% and 59% flock morbidity and mortality, respectively, with a case fatality rate of 74%. The striking histo-morphologic diagnosis of PPR was acute pneumonia and severe gastro-enteritis. A detailed experimental pathological study on Black Bengal goats infected with recent isolates is required

Economic analysis of tilapia-carp polyculture in a selected area of Bangladesh

Aquaculture is moving on the way of intensification to fulfill the increasing demand of protein as capture fisheries are declining. The study was conducted to identify the socioeconomic characteristics, analyze the tilapia-carp polyculture system, profitability of tilapia-carp polyculture, and credit profile of the stratified randomly selected 50 sample farmers from Sherpur district in Bangladesh. Primary data were collected through field survey using an interview schedule. Some statistical measures like average percentage and ratios were calculated. The findings revealed that 36% of the respondents belonged to the age group of 25-29 years, 68% belong to medium family size (5 to 6 people), 44% respondents’ education level was higher secondary, 44% respondents’ primary occupation was fish farming and 46 % of were belonged to in annual income level of Tk. 150001-200000 ($1770 -$2360). Average fingerlings released in the tilapia-carp polyculture were 24240 per hectare per year. Most of the fingerlings collected from private hatcheries. The annual per hectare production of tilapia and carp were 8028 kg and 11085 kg., respectively. Per hectare per year gross cost, gross margin, gross return and net return were Tk. 1093008 ($12897), Tk. 759447 ($8961), Tk. 1735455 ($20477) and Tk. 642447 ($7580), respectively. The BCR of tilapia-carp polyculture for cash cost was 1.78 and full cost was 1.59. About 20% of the respondents took loan from different sources and they received 84.51% of their applied amount and 84.73 % of the loan money used in productive purposes. Mortality of fingerlings, the high price of the ingredient, low price of fish, high interest rate and non-availability of good quality fingerlings at proper time were identified to be the major problems in conducting pond fish production. Government and other agencies should come forward to provide subsidized feed, technical supports and credit facilities for the tilapia-carp fish farmers to make the enterprise effectively