Chittagong University of Engineering & Technology

About: Chittagong University of Engineering & Technology is a education organization based out in Chittagong, Bangladesh. It is known for research contribution in the topics: Renewable energy & Dielectric. The organization has 1200 authors who have published 1444 publications receiving 10418 citations. The organization is also known as: Engineering College, Chittagong & Bangladesh Institute of Technology, Chittagong.

Deplorable Living Conditions of Female Workers: A Study in a Tea Garden of Bangladesh

Abstract: The study reveals the living conditions of the female laborers of tea garden in Bangladesh exploring the social and job environment with the inclusion of consciousness level as the deplorable scenario of their life styles. This research has been done in a tea garden of Sylhet district in Bangladesh namely Lackatoorah Tea Estate, as the study area, taken into account at random. It shows that female workers are being oppressed and suppressed in each and every sphere of life as from family residence to job field. It also exhibits very explicitly that 68 percent of female workers have no control over their own income. 94 percent have no hereditary property ownership though they are entitled to get it legally from their family. 92 percent females think that they are being physically tortured and mentally harassed by their husband, male members of family and also by representative of estates manager. 86 percent women want to keep small size of family but cannot play role in the decision making of child issue. The study is fully based on primary level data that followed stratified sampling method with triangulation research design and reviewing some related literatures from past research reports.

NaIn X 2 ( X = S, Se) layered materials for energy harvesting applications: first-principles insights into optoelectronic and thermoelectric properties

Abstract: In recent times, layered chalcogenide semiconductors have attracted great interest in energy harvesting device applications. In the present study, the structural, electronic, optical and thermoelectric properties of two isostructural chalcogenide materials, NaInS2 and NaInSe2 with hexagonal symmetry (R-3m) have been studied using the first principles method. A very good agreement has been found between our results with the available experimental and theoretical ones. The studied materials are semiconducting in nature as confirmed from the electronic band structure and optical properties. The strong hybridizations among s orbitals of Na, In and Se atoms push the bottom of the conduction band downward resulting in a narrower band gap of NaInSe2 compared to that of NaInS2 compound. Different optical (dielectric function, photoconductivity, absorption coefficient, reflectivity, refractive index and loss function) and thermoelectric (Seebeck coefficient, electrical conductivity, power factor and thermal conductivity) properties of NaInX2 (X = S, Se) have been studied in detail for the first time. It is found that all these properties are significantly anisotropic due to the strongly layered structure of NaInX2 (X = S, Se). Strong optical absorption with sharp peaks is found in the far visible to mid ultraviolet (UV) regions while the reflectivity is low in the UV region for both the compounds. Such features indicate feasibility of applications in optoelectronic sector. The calculated thermoelectric power factors at 1000 K for NaInS2 and NaInSe2 along a-axis are found to be 151.5 μW/cmK2 and 154 μW/cmK2, respectively and the corresponding ZT values are ~ 0.70. The obtained thermal conductivity along a-axis for both compounds is high (~ 22 W/mK).This suggests that the reduction of such high thermal conductivity is important to achieve higher ZT values of the NaInX2-(X = S, Se) compounds.

Mobile Apps for Foot Measurement in Pedorthic Practice: Scoping Review

Abstract: Background: As the use of smartphones increases globally across various fields of research and technology, significant contributions to the sectors related to health, specifically foot health, can be observed. Numerous smartphone apps are now being used for providing accurate information about various foot-related properties. Corresponding to this abundance of foot scanning and measuring apps available in app stores, there is a need for evaluating these apps, as limited information regarding their evidence-based quality is available. Objective: The aim of this review was to assess the measurement techniques and essential software quality characteristics of mobile foot measurement apps, and to determine their potential as commercial tools used by foot care health professionals, to assist in measuring feet for custom shoes, and for individuals to enhance their awareness of foot health and hygiene to ultimately prevent foot-related problems. Methods: An electronic search across Android and iOS app stores was performed between July and August 2020 to identify apps related to foot measurement and general foot health. The selected apps were rated by three independent raters, and all discrepancies were resolved by discussion among raters and other investigators. Based on previous work on app rating tools, a modified rating scale tool was devised to rate the selected apps. The internal consistency of the rating tool was tested with a group of three people who rated the selected apps over 2-3 weeks. This scale was then used to produce evaluation scores for the selected foot measurement apps and to assess the interrater reliability. Results: Evaluation inferences showed that all apps failed to meet even half of the measurement-specific criteria required for the proper manufacturing of custom-made footwear. Only 23% (6/26) of the apps reportedly used external scanners or advanced algorithms to reconstruct 3D models of a user’s foot that could possibly be used for ordering custom-made footwear (shoes, insoles/orthoses), and medical casts to fit irregular foot sizes and shapes. The apps had varying levels of performance and usability, although the overall measurement functionality was subpar with a mean of 1.93 out of 5. Apps linked to online shops and stores (shoe recommendation) were assessed to be more usable than other apps but lacked some features (eg, custom shoe sizes and shapes). Overall, the current apps available for foot measurement do not follow any specific guidelines for measurement purposes. Conclusions: Most commercial apps currently available in app stores are not viable for use as tools in assisting foot care health professionals or individuals to measure their feet for custom-made footwear. Current apps lack software quality characteristics and need significant improvements to facilitate proper measurement, enhance awareness of foot health, and induce motivation to prevent and cure foot-related problems. Guidelines similar to the essential criteria items introduced in this study need to be developed for future apps aimed at foot measurement for custom-made or individually fitted footwear and to create awareness of foot health.

Bangla text compression based on modified Lempel-Ziv-Welch algorithm

Abstract: Text compression algorithm performs compression at the character level. Bangla text has some unique features such as no distinct upper and lower case letter, consonant cluster (CC) and consonant with dependent vowel sign (CV) etc. The conventional Lempel-Ziv-Welch (LZW) algorithm is not suitable for compressing Bangle text. Therefore, in this paper, we propose a modified LZW (MLZW) algorithm which can compress Bangla text effectively and efficiently. In our proposed method, a dictionary with Unicode ranges from 1–90 is used for Bangla characters. The compression process is started with checking the input character. If input character is a part of CC or CV, then CC or CV is considered as a character and search it in the dictionary. If the character to be encoded is already in dictionary, encode it with the dictionary index. Otherwise, the character is added to the dictionary and is encoded with its corresponding dictionary index. Simulation results indicate that the proposed MLZW algorithm compresses Bangla text effectively and efficiently. We observed that the proposed MLZW provides higher compression rate approximately 3% for dictionary index and 33% for output sequence compared with LZW algorithm.