Evaluation of Computer Workstation Standards

This thesis aims at studying and evaluating the relevancy of the latest existing standards that have been established for setting up a computer workstation. The standards referred to in this study is the ANSI/HFES 100 (2007). Over the past two decades, standards have been updated to get along with new technology. However, by human nature, we does not always use these standards in the best way. Also, even if someone does set up their workstation in a way that are in accordance with standards, chances are that the user did not even know they were setting it in those ‘standard recognized’ way. It is more through their natural instinct and comfort that they do end up setting the workstation in that way. During computer tasks, people tend to shift their posture well outside of ‘standard advised’ posture ranges. If that is the case, then why enforce standards at all? That is exactly the intention of this thesis. By having two groups (one workstation set up according to standards and the other is set up by the user according to their comfort) the experimenter is able to compare and show that the postural behavior between the two groups are not significantly different and hence, the data gathered fails to show that standards could make any difference in the way a user sets up his/her workstation and also it does not affect the postural behavior or shifts in posture during the two-hour task. The study also tries to find out the effect of a two-hour computer task on stereoacuity and pupil diameter changes in participants . From the results and conclusion arrived in this study, companies can decide whether or not to spend valuable money and time in hiring an ergonomic expert in setting up workstations. Maybe the best thing they could do is provide the ergonomic office furniture and trust the judgement of the users to put it to best use

Modelling the Spatial Extent of Medium Energy Electron Precipitation

Jordens magnetosfære fungerer som et robust skjold, og beskytter planeten vår mot den nådeløse tilstrømningen av ladede partikler som hovedsakelig stammer fra solens solvind og fra de kosmiske strålene utenfor vårt solsystem. Mange av disse ladede partiklene blir fanget av jordens magnetosfære, og danner strålingsbeltene. En betydelig delmengde av disse fangede elektronene med energi >30 keV, kalt Medium Energy Electrons (MEE), dykker dypt inn i atmosfæren vår, og påvirker atmosfærisk kjemi og dynamikk direkte. Virkningen av MEE-nedbør på klimaet har blitt et voksende område av vitenskapelig interesse, spesielt gitt dens potensielle rolle i å ødelegge stratosfærisk og mesosfærisk ozon. Denne forskningen fordyper seg i å forstå den romlige fordelingen av MEE-nedbør og dens bredere implikasjoner. Ved å utnytte data fra Medium Energy Proton Electron Detector (MEPED) på ulike satellitter og sammenligne dem med geomagnetiske indekser, presenterer oppgaven en omfattende modell for å forutsi den geografiske omfanget av MEE-nedbør.The Earth's magnetosphere acts as a robust shield, protecting our planet from the relentless influx of charged particles originating primarily from the Sun's solar wind and from the cosmic rays beyond our solar system. Many of these charged particles get trapped by the Earth’s magnetosphere, forming the radiation belts. A significant subset of these trapped electrons with energy >30 keV, termed Medium Energy Electrons (MEE), dive deep into our atmosphere, directly influencing atmospheric chemistry and dynamics. The impact of MEE precipitation on the climate has become an emerging area of scientific interest, particularly given its potential role in destroying stratospheric and mesospheric ozone. This research delves into understanding the spatial distribution of MEE precipitation and its broader implications. Leveraging data from the Medium Energy Proton Electron Detector (MEPED) on various satellites and comparing it to geomagnetic indices, the thesis presents a comprehensive model to predict the geographic extent of MEE precipitation.Doktorgradsavhandlin

Fabrication of high quality periodic structures through convective assembly procedures

Techniques aimed at scalable realization of periodic structures from self-assembly of constituent building blocks, an approach that could supplant microfabrication procedures, are often constrained by the lack of diversity in packing arrangements achievable with assembly of simple constituents (e.g., spherical particles). In this work, we present a strategy to effectively pattern colloidal crystalline assemblies at two characteristic scales; achieving extensive non-classical particle packing amidst fully periodic, banded structural defects. We first introduce a scalable and robust approach to fabricate non-hexagonal crystals comprised of mono-sized spherical particles through introduction of periodically oscillating flow-fields during convective particle deposition. Through this technique, we report the discovery of extensive and tunable square-packed arrangements of monosized particles i.e., (100) fcc facets oriented parallel to the underlying substrate in self-assembled colloidal structures. Besides forming large (100) fcc crystalline domains with relatively few defects, the process also results in colloidal crystals having negligible variation in thickness while simultaneously yielding controlled proportions of both hexagonal and square-packed arrangements. The formation of domains of (100) fcc symmetry structures as a result of added vibration is robust across a range of micron-scale monosized spherical colloidal suspensions (e.g., polystyrene, silica) as well as substrate surface chemistries (e.g., hydrophobic, hydrophilic). In-situ visualization during self-assembly process as well as colloidal-crystal fabrication realized at varying frequency and amplitudes of vibration gives clues toward the mechanism of this flow-driven self-assembly method.In the second part of the work, we explore the introduction of volume defects in the uniformly-packed particle assemblies. Here, unlike randomly generated defects in packing structures, we demonstrate the formation of continuous, periodic banded defects comprised of particles with an fcc (110) packing configuration, and with tunable band periodicity. Studies aimed at discerning the specific effects of vibration conditions and meniscus properties help establish a mechanistic picture of the formation of fcc (110) banded structures based on stress relaxation in crystals through generation and movement of dislocations. The final chapters of the dissertation discuss how the convective assembly techniques could be efficiently used towards fabricating various devices for energy conversion and storage

Návrh systému odvodu spalin z měřícího standu vybaveného spalovacím motorem

Master thesis deals with design of the exhaust system for measuring stand consisting of an internal combustion engine which releases flue gas, a sampling system, a filter, a blower, a heat exchanger, a silencer and a safety system. The introduction describes the origin of the exhaust system, it’s problems and the purpose of the universal exhaust system. The theoretical part describes about the IC engine, it’s process and mechanism. It also has description about the emission of exhaust gases. The specification of the engine to be used is also described. The second half of the thesis is mainly focused on the design of the universal exhaust system and also the sampling system. The calculation for the pipe diameter and the design of the heat exchanger is also included. The conclusion contains the overview of all the task done by me during the thesis.Tato diplomová práce se zabývá návrhem systému pro odvod spalin z měřícího standu vybaveného spalovacím motorem s vnitřním spalováním. Navrhovaný systém se skládá z potrubního vedení, vzorkovací odběrové sondy, filtru, dmychadla, výměníku tepla, tlumiče a bezpečnostního systému. V úvodní části je vysvětlena potřeba vytvoření univerzálního výfukového systému. Teoretická část práce se zabývá spalovacími motory, jejich principy funkce a jejich konstrukcí. Jsou zde také popsány emise spalovacích motorů a specifikace parametrů pro návrh samotného systému odvodu spalin. Druhá část práce se věnuje návrhu univerzálního systému pro měřící daný stand. Tato část také obsahuje výpočet hlavních parametrů potrubí a návrh výměníku tepla. Závěr práce poté hodnotí, zda bylo při řešení práce dosaženo stanovených cílů.361 - Katedra energetikydobř

Monitoring in a Virtualized Environment

Monitoring solutions for virtualizedinfrastructure (VI) should evolve to collect, analyze andprovide configuration recommendation based on a broaderrange of operational metrics. A virtualized infrastructureis a complex interaction of hardware (servers, network andstorage), hosting variety of multi-tier application with specificservice level requirements and governed by their security andcompliance policies. Most existing solutions of today monitorand analyze only a subset of these interactions. The analysis andrecommendation obtained tend to optimize only particular aspectsof the infrastructure and can potentially introduce violations forthe others. A virtualized infrastructure is dynamic in nature,providing immense opportunities to automate configurationchanges to virtual machines, networks and storage. It deliversthe capability to administer the whole of infrastructure as a largeresource pool shared by multiple workloads. Monitoring solutionsthat look at only few aspects end up forcing administrators tocreate silos within the infrastructure that are specially designedto ensure that business service requirements are met for thespecific applications running there. A monitoring solution thatcan collect and analyze multiple aspects for assisting in decisionmaking and process automation can deliver greater efficiency tothe virtualized infrastructure.In this paper we argue the importance of having amonitoring solution that provides a holistic view of thevirtualized infrastructure. We discuss the need for solutions tobe capable of monitoring and analyzing a broader set of metricssuch as health of infrastructure components; performance ofoperating environment such as hypervisors, operating systemsand application running on them; capacity utilization indicatorsfor server, networks and storages; information available withconfiguration and change management database containingpolicies including security and compliance policies. We also takea look at what these broader set of metrics are and who wouldbe interested in them. The paper further proposes a monitoringframework for collecting and analyzing the above mentionedaspects of a virtual infrastructure to develop a more completesolution

A Quality of Experience-based Recommender System for E-learning Resources

Web services are a rapidly developing and generally acknowledged technology across all areas of management. Independent software systems that can be shared and called from anywhere online. The creation of educational tools (such LMSs, MOOCs, and e-learning) now typically makes use of web services. Having these learning tools readily accessible online is a great method to acquire and disseminate information. The primary objective of this paper is to describe how web services can effectively manage educational resources by leveraging Quality of Experience and to develop an effective E-learning recommender system in the context of web services that help the user choose a course based on his needs in terms of availability, cost, and reputation

ISOLATION, SCREENING AND CHARACTERIZATION OF ANTIBIOTIC PRODUCING ACTINOMYCETES FROM KAPULUPPADA PLASTIC WASTE DUMPING YARD, VISAKHAPATNAM

Objective: To isolate, screen and characterize antibiotic producing actinomycetes from Kapuluppada plastic waste dumping yard, Visakhapatnam.Methods: A total of 12 soil samples were collected, serially diluted and spread on starch casein agar supplemented with Rifampicin and Cycloheximide for inhibition of bacteria and fungi, respectively. Cross-streak method was used to check the antagonistic activity of isolated actinomycetes against bacteria and fungi. Crude extracts from submerged state fermentation were used for the production of antimicrobial compounds. Agar well diffusion method was used for antimicrobial activity of crude extracts against test organisms. The isolates were characterized by morphological, physiological and biochemical methods.Results: A total of 110 actinomycete isolates were isolated from plastic waste dumping yard. All isolates had shown antimicrobial activity against one or more tested bacteria/fungi. The crude extract of the isolates PD66 (12.2 mm), PD85 (11.5 mm) were most active against methicillin-resistant Staphylococcus aureus, PD4 (14.1 mm), PD66 (15.6 mm) were active against Pseudomonas aeruginosa, whereas the extracts of PD10 (19.2 mm), PD47 (19.8 mm), PD106 (19.1 mm) were active against Candida albicans, PD10 (14.6 mm), PD82 (15.7 mm) active against Saccharomyces cereviciae. The isolates had shown varying morphological, physiological and biochemical characteristics.Conclusion: The actinomycetes isolated from Kapuluppada plastic waste dumping yard were found to be most promising microorganisms for the production of antibacterial and antifungal antibiotics.Â

Task level disentanglement learning in robotics using βVAE

Humans observe and infer things in a disentanglement way. Instead of remembering all pixel by pixel, learn things with factors like shape, scale, colour etc. Robot task learning is an open problem in the field of robotics. The task planning in the robot workspace with many constraints makes it even more challenging. In this work, a disentanglement learning of robot tasks with Convolutional Variational Autoencoder is learned, effectively capturing the underlying variations in the data. A robot dataset for disentanglement evaluation is generated with the Selective Compliance Assembly Robot Arm. The disentanglement score of the proposed model is increased to 0.206 with a robot path position accuracy of 0.055, while the state-of-the-art model (VAE) score was 0.015, and the corresponding path position accuracy is 0.053. The proposed algorithm is developed in Python and validated on the simulated robot model in Gazebo interfaced with Robot Operating System

An Investigation of Order Review/Release Policies and Dispatching Rules for Assembly Job Shops with Multi Objective Criteria

AbstractThis work deals with the significant aspects of a simulation based experimental study of two shop floor control polices: order review/release (ORR) and dispatching rules for scheduling an assembly job shop in which multi-objective criteria is considered. A simulation of model of an assembly job shop which consists of one assembly work station with two machines and seven machining work stations with two machines in each work station is developed. Six dispatching rules and four ORR mechanisms identified from the literature are incorporated in the simulation model. Grey relational analysis is used for ranking the dispatching rule-ORR combinations. The performance measures considered in this study are mean flow time, mean tardiness and machine utilization. Simulation experiments have been conducted in an environment with products consisting of single level assembly structure, two level assembly structure and three level assembly job structures. The results indicate that Job Due Date rule with Interval Release policy performs better in comparison with the other dispatching rule- ORR combinations investigated in this study