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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Analys av databasstruktur och stored procedure i syfte att öka prestanda vid hämtning av data

Polprasert, Natthakon, Ahmadi, Mobin January 2019 (has links)
The Company X has a database that continuously increasing which causes the response time when retrieving data from the database increases the more data that is retrieved. Therefore, the company want an analysis of the database structures and stored procedures to see if there is a more efficient way to store and retrieve large datasets. Performance can have different meanings. Within the subject of computer systems, it could be factors such as transaction throughput, response time and storage space. But within the scope of this work performance is limited to the response time. One of the tables in the database is normalized and a few techniques are implemented for stored procedure that the company has not implemented to see if there have been any improvements in performance when retrieving data. The respond time for the various techniques implemented was measured in order to make a comparison on performance. The purpose of this thesis is to analyse database tables and how stored procedure can be improved to find a sustainable solution for the database in the future. Question to the work are: How can the database structure be improved with the aim of increasing performance of data retrieval? Which techniques can improve stored procedure performance when it comes to retrieving large amount of data? The result of this work was that normalization has reduced the respond time for large data retrieval. One of the stored procedure techniques which is called sp_executesql was one of the best techniques which improved the performance of execution time the most when it came to retrieve large amount of data. / Företaget X har en databas som kontinuerligt ökar i storlek vilket detta leder till att svarstiden vid hämtning av data från databasen öka ju mer data som hämtas. Därför vill företaget X att databasstrukturen och stored procedure skulle analyseras för att se om det fanns ett effektivare sätt att lagra samt hämta stora mängder data på. Prestanda kan ha olika betydelser; inom databassystem handlar det om olika faktorer som transaktionsgenomströmning, svarstid och lagringsutrymme. I detta arbete begränsas prestanda till svarstiden. En av tabellerna i databasen normaliseras och sedan implementeras ett antal tekniker för stored procedure som företaget inte har implementerat. Detta för att kunna se om det har skett förbättringar i prestanda vid hämtning av data. Därefter mätes svarstiden för de olika teknikerna som implementerades för att kunna göra en jämförelse på prestanda. Syftet med arbetet är att analysera databastabeller samt analysera hur stored procedure kan förbättras för att hitta en hållbar lösning för databasen i framtiden. Frågeställningar till arbetet är: Hur kan databasstrukturen förbättras i syfte att öka prestanda vid hämtning av data? Samt vilka tekniker kan förbättra prestanda för stored procedure vid hämtning av stora datamängder? Resultatet av arbetet blev att med hjälp av normalisering har svarstiden minskat för hämtning av stora datamängder samt att sp_executesql är den teknik inom stored procedure som är överlägset bäst av de tekniker som har implementerats när det gäller prestanda vid hämtning av stora datamängder.
22

Spatial distribution, dispersal behavior and population structure of Tribolium castaneum herbst (Coleoptera: tenebrionidae)

Semeao, Altair Arlindo January 1900 (has links)
Doctor of Philosophy / Department of Entomology / James F. Campbell / Phillip E. Sloderbeck / Robert "Jeff" J. Whitworth / Knowledge of factors influencing the establishment, persistence and distribution of stored-product pests aids the development of effective Integrated Pest Management (IPM) programs in food storage and processing facilities. This research focused primarily on Tribolium castaneum, which is one of the most important pests of mills. Populations of T. castaneum from different food facilities can potentially be interconnected by either their own dispersal behavior or by human transportation. Population genetic structure analyses based on microsatellites and other insertion-deletion polymorphisms (“indels”) showed that populations from different mills around the US are genetically distinct from each other, but the level of differentiation was not correlated with the geographic distance. A potential source of insect infestation within a food facility is spillage that accumulates outside or movement from bulk storage facilities on site. Results from three facilities showed that most stored-product species were captured both inside and outside buildings, but T. castaneum was rarely captured outside of the facilities. Spatial distribution of all species outside was associated with the proximity of buildings, not necessarily with areas with accumulated spillage. T. castaneum populations inside facilities are potentially exposed to frequent genetic bottlenecks resulting from structural fumigations. Changes in allele frequencies through time, based on the analysis of microsatellites and other indels in individuals collected in a mill, confirmed bottleneck effects. To understand how spatial distribution of T. castaneum within a mill could be influenced by environmental and physical factors, a range of variables were measured at each trap location. There was significant variation among trap locations regarding beetle captures and the variables measured, but increase in beetle captures correlated only with increase in temperature and spillage production. Tribolium castaneum response to visual cues could influence attraction to pheromone and kairomone olfactory cues used in traps. Results of laboratory experiments showed that adults respond to tall narrow black shapes and placing traps in front of these shapes can increase captures. This research provides new insights into factors influencing the spatial distribution of T. castaneum and could help in improving monitoring programs for this important pest of the food industry.
23

Efficacy of a synthetic zeolite against five species of stored-grain insects on concrete and wheat

Yao, Kouame January 1900 (has links)
Master of Science / Department of Grain Science and Industry / Bhadriraju Subramanyam / A synthetic zeolite (Odor-Z-Way, sodium aluminum silicate) used for odor adsorption was tested for its ability to control adults of stored-grain insects on wheat and on concrete petri dishes used to simulate floors of empty bins. Insect species tested included unsexed adults of the lesser grain borer, Rhyzopertha dominica (F.); rice weevil, Sitophilus oryzae (L.); maize weevil, Sitophilus zeamais (Motschuslky); red flour beetle, Tribolium castaneum (Herbst), and sawtoothed grain beetle, Oryzaephilus surinamensis (L.). Two formulations were evaluated under laboratory conditions (28±1⁰C and 65±1% r.h.): coarse zeolite (with 90% of particles having a mean diameter at or below 155 µm) and fine zeolite (with 90% of particles having a mean diameter at or below 47.0 µm). On concrete, arenas in 9-cm diameter Petri dishes were sprinkled with the synthetic zeolite to provide deposits of 0 (control), 5 and 10 g/m[superscript]2. Mortality was assessed at times ranging from 10 minutes to 24 hours followed by 48 hours recovery on wheat. Mortality in adults of the five species increased as the rate of application and the duration of exposure increased. Concrete Petri dishes sprinkled with the fine zeolite yielded percent mortality greater or equal to that observed with the coarse zeolite- sprinkled Petri dishes. Bioassays on wheat were conducted using two dosage rates: 0.1 to 3.0 g/kg for R. dominica and 0.05 to 1.0 g/kg for the other insect species. Mortality was assessed 7 days post- infestation. A concentration of 0.75 g/kg of fine or coarse zeolite achieved 100% mortality in adults of S. zeamais, T. castaneum, and O. surinamensis. All adults of S. oryzae were killed using 0.50 g/kg of coarse or fine zeolite. Adults of R. dominica were the least susceptible: 2.50 g/kg of fine zeolite and 3.0 g/kg of coarse zeolite were required for 100% mortality. Mortality generally increased with the concentration of zeolite applied on wheat. Efficacy was not related to particle size. This is the first study showing the efficacy of a synthetic zeolite against adults of five species of stored-product insects on concrete and wheat. Synthetic zeolites can be a suitable alternative to currently used pesticides for treatment of empty bin floors and stored wheat for insect control.
24

Residual toxicities of synergized pyrethrins and methoprene applied as aerosol insecticides

Sutton, April E. January 1900 (has links)
Master of Science / Department of Entomology / Franklin Arthur / Kun Yan Zhu / Tribolium spp. are major pests in structures used for the processing and storage of grain-based products (e.g., flourmills, warehouses, retail stores). Consumers and regulators have little tolerance for insect-damaged or contaminated food products. The direction and breadth of pest-control strategies in the food industry have changed significantly over the past few years, creating the need to optimize insecticides through improved integrated pest management (IPM) techniques, specifically through the identification of new control agents that are low in mammalian toxicity, as well as any factors that might affect susceptibility to these agents. There is currently renewed interest in developing reduced-risk, low toxicity chemicals that can be effectively utilized in a setting in which grain and other food commodities are vulnerable to insect infestation, as a means of replacing outdated, and at times, less effective methods of insect control. Over the past decade, developed countries have made significant progress toward alternative insect control strategies by employing a variety of applied insecticides. Two classes of insecticide include natural pyrethrum and insect growth regulators (IGRs), which are substances that mimic insect hormones essential to normal development and reproduction. Pyrethrin is a highly efficient, broad spectrum, botanical insecticide that causes a rapid knockdown in exposed insects. Synergists are used to extend the economic usage of natural pyrethrins and because pyrethrum is rapidly metabolized, it is often mixed with a synergist. Methoprene, a juvenile hormone analog, is labeled as an aerosol and surface treatment inside mills, warehouses and other food storage facilities. There is little recent research with large-scale aerosol applications in stored-food facilities; furthermore, there are few published references regarding the efficacy of using methoprene in combination with synergized pyrethrin, in aerosol form. Therefore, the purpose of this research was to evaluate the use of aerosol applications of two aerosol concentrations on flour and finished stored-product packaging materials for the control of Tribolium spp. Results of this research show that T. castaneum are effectively controlled with 1% aerosol application, while the 3% formulation is required to effectively control T. confusum. With regards to the various packaging material surfaces, few differences between the surfaces emerged.
25

FLIGHT INSTRUMENTATION TELEMETRY FOR AEROSPACE APPLICATION

RAJYALAKSHMI, P. S., RAJANGAM, R. K. 10 1900 (has links)
International Telemetering Conference Proceedings / October 13-16, 1986 / Riviera Hotel, Las Vegas, Nevada / In Aerospace missions it is often required to have a flexible telemetry system for carrying out flight test on aircraft, in which the bit rate, sampling rate and the number of channels can be programmed. This enables the pilot of the aircraft to reconfigure the telemetry system to suit any particular test missions. An L-Band PCM/FM Telemetry System containing a Stored Programme Multiplexer, 12 bit ADC and other digital interfaces for carrying out the measurements on Speed, Events, etc has been developed as a flight instrumentation telemetry for HAL, India. This paper not only presents complete details of the system, which was qualified to meet MIL-5422 levels but also the performance of the system during actual aircraft missions.
26

Investigating consumer expectations for a bankcard service in the South African food and retail industry : a servqual application

Hechter, Tremaine 03 1900 (has links)
ENGLISH ABSTRACT: South Africans have over the past few years called for more affordable banking. Some retailers have looked at the opportunities and entered into the financial services space. The question remains as to why consumers would want to pay bank charges to have a bankcard when the card is actually used to pay for goods at retailers who can deliver the service themselves at a saving to both the customer and the retailer? The aim of this study was to determine customer expectations for a bankcard service offering in the South African food and retail industry with the emphasis on consumer behaviour and expectations, bankcards, services and SERVQUAL. This is a SERVQUAL application and a comprehensive literature of this topic is followed with a questionnaire outlining the expectations for such a service. SERVQUAL measures the gap between expectations and perceptions. In this study only expectations are measured as one of South Africa’s major food retailers was used and they do not offer this service at present. Various hypotheses were constructed to measure the expectations for attributes around this service. The attributes were trust, safety, cost, loyalty, open-loop versus closed-loop and mobile. Customer preference on payment methods was also determined when paying for different basket sizes. The results showed overwhelming evidence in favour of expectations for a bankcard service offering by retailers. This research can be used to address the major challenge South Africans and retailers face with high banking charges and address the challenge everyone has with regards to the risk associated with cash handling. Education on this topic is paramount and this could further pave the way for mobile phones replacing bankcards in the future which have also been researched as part of this topic. Further research is necessary to determine the characteristics of a bankcard product in a retail environment.
27

Optical Spectroscopy of Mass-selected Ions in the Gas Phase

Forbes, Matthew William 12 August 2010 (has links)
Optical spectroscopy combined with mass spectrometry provides a unique opportunity to probe the intrinsic properties of biologically-relevant ions in the gas phase, free from the interfering effects of solvent interactions in the condensed phase. Electrospray ionization allows large biomolecules to be transferred intact into the gas phase for mass analysis. Modern mass spectrometers provide excellent sensitivity, mass-resolution and can efficiently isolate a single ionic species from a complex mixture. However, the extent to which biomolecules retain their solution-phase conformations in the gas phase is largely unknown. Therefore, there is considerable interest in applying spectroscopic methods to biological ions in vacuuo. Due to the low number densities of ions in storage devices, traditional absorption measurements are not feasible, requiring more sensitive analytical methods. Two such techniques are laser-inducedfluorescence (LIF) and photo-dissociation (PD) action spectroscopy, both of which measure the consequence of absorption. The work in this dissertation describes applications of optical spectroscopic methods to interrogate mass-selected ions using a variety of ion storage apparatus including a Fourier transform ion cyclotron resonance mass spectrometer, a quadrupole ion trap and an electrostatic ion storage ring. First, the conformations of small cationized arginine complexes have been investigated using infrared multiple-photon dissociation (IRMPD) action spectroscopy in the IR fingerprint region of the spectrum (200-1800 cm-1). Second, an apparatus incorporating a quadrupole ion trap has been constructed in our laboratory to perform LIF and PD-action spectroscopy. The gas-phase fluorescence and photodissociation properties of three Rhodamine dyes have been investigated including fluorescence excitation and dispersed fluorescence spectra. Finally, the latter chapters describe the use of electronic action spectroscopy to investigate a model chromophore of the green fluorescent protein (GFP), p-hydroxybenzylidene-2,3-dimethylimidazolone (HBDI). The body of work in this dissertation highlights the integration of gas-phase spectroscopy and mass spectrometry to elucidate the fundamental photophysical properties of biological and related ions.
28

Stored-grain insect management with insecticides: evaluation of empty- bin and grain treatments against insects collected from Kansas farms

Sehgal, Blossom January 1900 (has links)
Master of Science / Department of Grain Science and Industry / Bhadriraju Subramanyam / The insecticides, β-cyfluthrin and chlorpyrifos-methyl plus deltamethrin, are approved in the United States for treating empty bin surfaces. Chlorpyrifos-methyl plus deltamethrin and spinosad insecticides are approved for direct treatment of wheat. The efficacy of commercial formulations of β-cyfluthrin and chlorpyrifos-methyl plus deltamethrin at labeled rates was evaluated against adults of 16 field strains of the red flour beetle, Tribolium castaneum (Herbst); seven strains of sawtoothed grain beetle, Oryzaephilus surinamensis (L.); and two strains of the lesser grain borer, Rhyzopertha dominica (F.). Concrete arenas in plastic Petri dishes (9 cm diameter) were used to simulate the concrete floor of empty bins. The time for ~100% knockdown and mortality of adults of laboratory strains of the three species was first established by exposing them to insecticide-treated concrete surfaces for 1 to 24 h. Adults of field strains of each species were exposed to specific established insecticide-time combinations. Mortality of all species was lower than knockdown, suggesting recovery after seven days when placed on food. Chlorpyrifos-methyl plus deltamethrin did not control all R. dominica and most O. ]surinamensis field strains. β-cyfluthrin was extremely effective against R. dominica but ineffective against T. castaneum and O. surinamensis field strains, even at four times the high labeled rate. Field strains of R. dominica were highly susceptible to spinosad and chlorpyrifos-methyl plus deltamethrin at labeled rates on hard red winter wheat. Strains of T. castaneum and O. surinamensis were susceptible only to the latter insecticide. Dose-response tests with spinosad on the two least susceptible field strains of each species showed the lethal dose for 99% mortality (LD[subscript]99) for T. castaneum and R. dominica field strains were similar to that of the corresponding laboratory strains. Corresponding values for the two O. surinamensis field strains were significantly greater (~6 times) than the laboratory strain. The effective dose for progeny reduction (ED[subscript]99) of only one R. dominica field strain was significantly greater (~2 times) than that of the laboratory strain. The baseline susceptibility data of field strains of three insect species to spinosad will be useful for monitoring resistance development once this product is commercially released as a grain protectant.
29

Packaging technologies for the control of stored-product insects

Scheff, Deanna Sue January 1900 (has links)
Doctor of Philosophy / Department of Grain Science and Industry / Subramanyam Bhadriraju / Hulya Dogan / Larvae of the Indian meal moth, Plodia interpunctella (Hübner), have the ability to invade or penetrate packaging materials and infest the food within. Energy bars with three polypropylene packaging types were challenged with eggs (for first instars), third, and fifth instars of P. interpunctella to determine package resistance to larvae at 28°C and 65% r.h. to determine which provided the greatest protection against P. interpunctella larval penetration. Third and fifth instars showed a higher propensity to infest all packaging variations. First instars showed a reduction in package pentration abiltiy compared to third and fifth instars. Methoprene is an insect growth regulator labeled in the USA for use as an aerosol spray, a residual surface treatment, and as a grain protectant, and recently has been impregnated into a polymer-based packing film to prevent insect infestations of packaged products. The objectives of these studies were 1) determine the effect of short term exposure time and temperature on four week old larvae, continual exposure on egg-to-adult emergence of beetles, and sub-lethal effect on adults of the red flour beetle, Tribolium castaneum (Herbst) and warehouse beetle, Trogoderma variabile Ballion, on the inside and outside surfaces of methoprene-treated woven packaging material at 27 and 32°C at 60% r.h.; 2) evaluate fecundity, egg hatch, and egg-to-adult emergence of T. castaneum and T. variabile, when exposed to two methoprene-impregnated polymer packaging on the inside and outside surfaces at 27 and 32°C at 60% r.h.; and 3) determine the effect of methoprene-treated foil packaging on larval emergence, penetration, and invasion ability of T. variabile and P. interpunctella at 27°C and 60% r.h. Short term exposure results indicated that adult emergence from larvae of T. castaneum and T. variabile decreased with increasing exposure time. The number of eggs laid per female of T. castaneum and T. variabile did not vary from their controls. Continual exposure demonstrated 100% supression of T. castaneum adult emergence, irrespective of exposure to outside or inside surfaces. T. variabile exposed to inside surfaces were unaffected and normal adult emergence was reduced in those exposed to outside surfaces.. The number of T. variabile eggs laid per female was not significantly different among polymer packaging types. The methoprene-treated polyethylene terephthalate to polyethylene packaging, PET-PE reduced the number of T. castaneum eggs laid per female. Both polymer packaging reduced the percent hatch of both species. No T. castaneum adults emerged on the inside surface of PET-PE and both sides of the polyethlyene to polyethylene (PE-PE). Egg-to-adult emergence of T. variabile was arrested at the pupal stage on the outside surface of PE-PE packaging. The PET-PE packaging greatly reduced the number of normal adults by 87 to 97% when exposed to inside surfaces at both temperatures. The foil packaging had no significant effect on hatch of either species. T. variabile were unable to penetrate/invade any foil packages. P. interpunctella invaded all packaging containing pinholes. Therefore, continual exposure of T. castaneum and T. variabile to methoprene impregnated packaging could be a vaiable tool to protect food packages.
30

Stored-grain Monitoring Utilizing Radio Wave Imaging

Asefi, Mohammad 20 June 2016 (has links)
Storage of large amounts of grain post-harvest is common during drying, distribution and preservation of crops. During storage, where grain is usually held in a large metallic container or bin, changes in temperature, moisture, and insect infestation can cause grain to spoil annual post-harvest crop losses are estimated up to 30% in some countries while Canadian losses of 2% exceed a billion dollars. Currently, locally-sensitive temperature and moisture sensors are a common way to monitor grain bins. Sensors are generally strung on heavy duty cables that can withstand the forces generated when unloading grain. This monitoring method provides a coarse sampling of the storage environment due to system cost and the fact that using many sensor cables would require significantly reinforcing the bin. Further, these cables are not suitable for monitoring stored crops that are dried by a combination of stirring and aeration. Over the past four years, I have developed multiple electromagnetic imaging based grain-monitoring systems with the goals of overcoming the deficiencies of existing sensor technology and allowing farmers and distributors a robust way to preserve our food stores and increase revenue. The proposed technology aims to produce global, quantitative images of grain properties throughout the bin from measurements taken by a few side-mounted antennas used to interrogate the bin contents. To develop this technology intensive research was put into the design of low profile, robust antennas as well as numerical analysis of the effects of different field distributions within conducting boundaries. Both electric and magnetic field sensitive antennas were built and tested in small lab-scale as well as full-scale grain bins to experimentally evaluate the performance of such imaging system. This thesis provides details on different system designs and analysis and describes the advantages and challenges associated with the techniques described. / October 2016

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