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Infant Birth Outcomes Among Substance Using Women: Why Quitting Smoking during Pregnancy Is Just as Important as Quitting Illicit Drug UseBailey, Beth A., McCook, Judy G., Hodge, Alexis, McGrady, Lana 22 March 2011 (has links)
Poor birth outcomes are associated with illicit drug use during pregnancy. While prenatal cigarette exposure has similar effects, cessation of illicit drug use during pregnancy is often prioritized over cessation of smoking. The study goal was to examine the impact of pregnancy tobacco use, relative to use of illicit drugs, on birth outcomes. Women were recruited at entry to prenatal care, with background and substance use information collected during pregnancy. Urine drug screens were performed during pregnancy, and the final sample (n = 265) was restricted to infants who also had biologic drug testing at delivery. Participants were classified by pregnancy drug use: no drugs/no cigarettes, no drugs/cigarette use, illicit drugs/no cigarettes, and illicit drugs/cigarette use. Groups differed significantly on infant birthweight, but not gestational age at delivery after control for confounders including background and medical factors. Among women who smoked, the adjusted mean birthweight gain was 163 g for those not using hard illicit drugs, while marijuana use had no effect on birth weight beyond the effect of smoking cigarettes. Women who used hard illicit drugs and did not smoke had an adjusted mean birthweight gain of 317 g over smokers. Finally, women who refrained from hard illicit drugs and smoking had a birthweight gain of 352 g. Among substance using pregnant women, smoking cessation may have a greater impact on birthweight than eliminating illicit drug use. Intervention efforts should stress that smoking cessation is at least as important to improving pregnancy outcomes as abstaining from illicit drug use.
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DETECTION AND SUB-PIXEL LOCALIZATION OF DIM POINT OBJECTSMridul Gupta (15426011) 08 May 2023 (has links)
<p>Detection of dim point objects plays an important role in many imaging applications such as early warning systems, surveillance, astronomy, and microscopy. In satellite imaging, natural phenomena, such as clouds, can confound object detection methods. We propose an object detection method that uses spatial, spectral, and temporal information to reject detections that are not consistent with a moving object and achieve a high probability of detection with a low false alarm rate. We propose another method for dim object detection using convolutional neural networks (CNN). The method augments a conventional space-based detection processing chain with a lightweight CNN to improve detection performance. For evaluation of the performance of our proposed methods,</p>
<p>we used a set of curated satellite images and generated receiver operating characteristics (ROC).</p>
<p><br></p>
<p>Most satellite images have adequate spatial resolution and signal-to-noise ratio (SNR) for the detection and localization of common large objects, such as buildings. In many applications, the spatial resolution of the imaging system is not enough to localize a point object or two closely-spaced objects (CSOs) that are described by only a few pixels (or less than one pixel). A low signal-to-noise ratio (SNR) increases the difficulty such as when the objects are dim. We describe a method to estimate the objects’ amplitudes and spatial locations with sub-pixel accuracy using non-linear optimization and information from multiple spectral bands. We also propose a machine</p>
<p>learning method that minimizes a cost function derived from the maximum likelihood estimation of the observed image to determine an object’s sub-pixel spatial location and amplitude. We derive the Cramer-Rao Lower Bound and compare the proposed estimators’ variance with this bound.</p>
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Computer Model Emulation and Calibration using Deep LearningBhatnagar, Saumya January 2022 (has links)
No description available.
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Review of Earlier Thesis work at BTH Related to Packaging and Packaging FieldAhmad, Abu ul Hasnat January 2021 (has links)
This work aims at giving a systematic review of the numerical approaches and obtained results published in recent years. Focus is set on both the recent trends and achievements as well as challenges and open questions. Thesis critically reviews work done in previous thesis related to food packaging material and design, at Blekinge Institute of Technology with the collaboration of Tetra Pak liquid food packaging company. Here, 27 numbers of master’s thesis are critical review all the while using 4 PHD works for referencing. Focus of these thesis works relates to the mechanics and its sub-branch fracture mechanics. Due to this all the theory related to mechanics and fracture mechanics, which is compulsory to know for understanding is defined initially. Main material which are under consideration throughout the work are PP, LDPE, PET-LDPE, and aluminum foil. As three materials are used in the liquid food packaging which are PE, paper board and aluminum. Uses of this material and there required physical properties are measured. Testing methods which are used to check whether the material meets the required parameters are tensile testing, tear testing, peel testing and shear test. Also, some methods are used along with these tests to perform the test more precisely, to evaluate and compare result i.e., Nakajima test, Digital image correlation. DIC testing technique is used to compare the results obtained from simulation. It is also understood that DIC method provided the user with increased quality of obtained results. Most of the topics of discussions have been reviewed for corresponding thesis, displaying the used ideas, theory, applied experimentation and realized conclusions. Using these above it was able to derive a conclusion based on the developed research questions and hypothesis. Defined problems in previous work are studied also solution as a future work is suggested to overcome these problems. Mainly the slippage issue while holding PE in clamps. Furthermore, various development is discussed which is done to introduce new material which is more possible being used in the future.
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Monitoring Land Use and Land Cover Changes in Belize, 1993-2003: A Digital Change Detection ApproachEk, Edgar 18 December 2004 (has links)
No description available.
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An Analysis of the Correspondence of Environmental Coverage in Ohio's Six Major Metropolitan Newspapers to Citizen Perception of Environmental ProblemsMueller, John F. 25 April 2006 (has links)
No description available.
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Optimization of the process for reuse of steel beams using parametric design / Optimering av processen för återbruk av stålbalkar med hjälp av parametrisk designAsaad, Muhannad, Husseini, Abdulla January 2021 (has links)
Planet Earth's climate naturally varies over time, however the rapid change that is now takingplace is due mainly to human influence. Buildings and real estate sector's emissions ofgreenhouse gases is responsible for approximately 20,6% of Sweden’s total emissions ofgreenhouse and 33% of energy used 2018. Therefore, energy efficiency, a reduction in energyand energy supply with a low effect on the environment are necessary to manage environmentalquality objectives. Steel production requires high temperatures, and thus high energy consumption, both for meltingand processing, which in turn produces carbon dioxide emission into the air. Steel recycling isa much-needed innovation to save energy and reduce the amount of emission of carbon dioxide.However, even greater energy savings, and a reduction in the effect on the environment, can beachieved by reusing steel components instead of recycling or producing new steel. Despite thelarge environmental incentive, only a very small proportion of Sweden's total structural steel isreused. To date the process for reusing steel components has been unclear and needs to be clarified. Amajor challenge in the process is to create a marketplace where suppliers and buyers can meet.The purpose of this report is to investigate the possibility of parametric design to develop a toolthat selects suitable reusable steel beams from hundreds of beams which fit into new contextsin accordance with certain desired conditions. This work results in a program or script, where the user specifies his/her values and requirementsthat will apply to the selected beam. Furthermore, the program shows the beams that meet therequirements of users and sorts them in an environmentally friendly order. This program isexpected to help designers select the right reusable beam in the right place in a new project. The script was created to handle I- and H-beams using the program Rhinoceros-Grasshopper asa platform for parametric design and calculation. The program includes calculations for crosssectionalclasses, uniaxial and multi-axial bending without regard to the phenomena of lateraltorsional buckling, and transverse force where shear buckling is considered. However, the scriptdoes not handle beams with cross-section class 4. In conclusion the result of this study, which is the script, shows that it is possible to develop aparametric tool that calculates, analyzes and selects the beams that best suit the user's needs andwhere the selected beams are displayed in an environmentally friendly order. Such a tool canalso facilitate the process of reusing steel beams. It saves time and money as compared toperforming the selection manually. In addition, it opens people’s eyes to new efficient methodsand ways of thinking in the field of reusing. It can also be considered as an incentive forincreased reuse of steel beams while reducing the negative effect on the environment and whilesaving energy and natural resources. / Världens utsläpp av växthusgaser har under en lång period ökat mycket och detta ställer ossinför en global utmaning. Bygg- och fastighetssektorns utsläpp står för cirka 20,6% av Sverigestotala utsläpp av växthusgaser och 33% av energianvändningen år 2018. Därför ärenergieffektivisering, minskad energiförbrukning och energitillförsel med låg påverkan påmiljön nödvändiga för att klara miljökvalitetsmålen. Ståltillverkning kräver höga temperaturer, och därmed hög energiförbrukning, både försmältning och bearbetning, vilket i sin tur ger en del utsläpp i luften. Återvinning av stål är enbra strategi för att spara energi och minska mängden utsläpp av växthusgaser. Men ännu störreenergibesparingar, och minskning av miljöpåverkan, kan uppnås om stålkomponenteråteranvänds i stället för att återvinna eller tillverka nytt stål. Trots det stora miljöincitamentetåterbrukas väldigt liten andel av Sveriges totala konstruktionsstål. Processen för återbruk av stålkomponenter ser otydlig ut och den behöver fastställas. En storutmaning i processen ligger i att skapa en marknadsplats där säljare och köpare kan mötas. Dettahar en stark koppling till syftet med rapporten som är att utreda möjligheten med parametriskdesign att ta fram ett verktyg som väljer ut lämpliga återbrukbara stålbalkar av en databas nedett stort antal balkar, som passar in i nya sammanhang efter vissa önskade förutsättningar. Resultatet av arbetet blir ett verktyg eller skript, där användaren anger sina värden och krav somkommer att ställas på den utvalda balken. Vidare visar skriptet de balkar som klarar av kravenfrån användaren och sedan sorterar dem med avseende på minimal miljöpåverkan. Programmetförväntas hjälpa konstruktörerna att välja ut rätt återbrukbara balk till rätt plats i ett nyttsammanhang. Det framtagna verktyget är skapat för att hantera I- och H-balkar med hjälp av programmenRhinoceros-Grasshopper som en plattform för en parametrisk design och beräkning. Iprogrammet ingår beräkningar för tvärsnittklasser, enaxlig och fleraxlig böjning utan hänsyn tillvippning samt tvärkraft där hänsyn tas till skjuvbuckling. Skriptet hanterar dock inte balkar medtvärsnittklass 4. Resultatet av denna studie, vilket är skriptet, visar att det är praktiskt möjligt att ta fram ettparametriskt verktyg som beräknar, analyserar och väljer ut de balkar som passar bäst föranvändarens behov. Verktyget kan även underlätta processen för återbruk av stålbalkar,eftersom det sparar tid och pengar jämfört med ett manuellt urval. Dessutom öppnar det ögonenför nya effektiva arbeten och tänkesätt inom området återbruk. Det kan även anses vara ettincitament för en ökad återanvändning av stålbalkar och minskning av miljöpåverkan, vilketbidrar till energi- och resursbesparingar.
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Exploring Parental Actions to Finance Higher EducationSikes, S. Mark 01 April 1998 (has links)
The purpose of this study was to examine parental actions to finance higher education. Data were analyzed from the 1995-96 National Postsecondary Student Aid Study (NPSAS: 96).
Results of this study indicated that gender, race, housing status, and attendance status of students were factors in the amount of loans that was assumed by parents. Further results indicated that parent'9s marital status, total parent contribution, parent income, the cost of attending, and institutional control were also factors in the amount of loans that were assumed by parents.
The age of students and the amount of parent savings did not effect the percentage of parents who assumed loans nor did it effect the amount of loans that were assumed by parents.
Recommendations for future research include a continued focus on how families, as a whole, are financing higher education, repayment practices and default rates of parents who assumed loans to pay for higher education, specific types of loans that parents use to fund higher education, parental debt and what ratio of their debt is due to educational loans. / Master of Arts
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Structural damage detection using ambient vibrationsTadros, Nader Nabil Aziz January 1900 (has links)
Master of Science / Department of Civil Engineering / Hani G. Melhem / The objective of this research is to use structure ambient random vibration response to detect damage level and location. The use of ambient vibration is advantageous because excitation is caused by service conditions such as normal vehicle traffic on a highway bridge, train passage on a railroad bridge, or wind loads on a tall building. This eliminates the need to apply a special impact or dynamic load, or interrupt traffic on a bridge in regular service.
This research developed an approach in which free vibration of a structure is extracted from the response of this structure to a random excitation in the time domain (acceleration versus time) by averaging out the random component of the response. The result is the free vibration that includes all modes based on the sampling rate on time. Then this free vibration is transferred to the frequency domain using a Fast Fourier Transform (FFT). Variations in frequency response are a function of structural stiffness and member end-conditions. Such variations are used as a measure to identify the change in the structural dynamic properties, and ultimately detect damage.
A physical model consisting of a 20 × 20 × 1670 -mm long steel square tube was used to validate this approach. The beam was tested under difference supports conditions varying from a single- to three-span continuous configuration. Random excitation was applied to the beam, and the dynamic response was measured by an accelerometer placed at various locations on the span. A numerical model was constructed in ABAQUS and the dynamic response was obtained from the finite element model subjected to similar excitation as in the physical model. Numerical results were correlated against results from the physical model, and comparison was made between the different span/support configurations. A subsequent step would be to induce damage that simulates loss of stiffness or cracking condition of the beam cross section, and that would be reflected as a change in the frequency and other dynamic properties of the structure.
The approach achieved good results for a structure with a limited number of degrees of freedom. Further research is needed for structures with a larger number of degrees of freedom and structures with damage in symmetrical locations relative to the accelerometer position.
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Generation of 3D autostereoscopic integral images using computer simulated imaging systemsSalih, Shafik January 2015 (has links)
Production of artificial Three-Dimension (3-D) images was the aim of many researches over hundreds of years. 3-D images are the images that create sense of depth when viewing them. 3-D images are closer to the real world scenes than 2-D images due to the 3-D effect or the sense of depth the 3-D images provide. Sense of depth can be caused by binocular cues including convergence and parallax. Convergence is created by the difference between the angles of the left eye and the right eye viewing axes. Parallax is the effect of viewing with one eye a view of the scene that is inherently shifted to the view seen by the other eye. Several techniques have targeted the creation of 3-D images with the mentioned cues. The technique is preferred when it is able to create 3-D images so that the viewer can view these images without wearing special glasses and the occurrence of viewer fatigue. Integral photography that was invented in 1908 is able to meet the previous requirements. Based on integral photography, several techniques, research and studies have been published. The purposes of this thesis include the computer simulation of flexible integral photography systems, the computer generation of good quality 3-D static and animated integral images using the simulated systems, optimising the generation process to be more accurate, less expensive, more effective, and faster, and producing a portable specialist software tool to achieve these targets. New techniques and algorithms are needed to meet these purposes. A literature survey was carried out about the closest researches and studies to the subject of computer-generated integral images; these were compared with the new techniques introduced in this study to prove the advantages and the necessity of these new techniques. The closest technique to the suggested techniques was implemented using more developed tools to compare the quality of the resulting integral images with the targeted integral images that are going to be produced using the tools and algorithms proposed in this thesis. A method to simulate an imaging system and produce integral images based on the new technique of dividing the view volume of the scene was introduced, explained, proved, and implemented with a program designed for this purpose. To optimise the processing time and the image quality, the previous method is developed, new features are added to the resulting integral images, and better performance was achieved by introducing the method of Displacing the Virtual Camera Target (DCT). Application software with Graphical User Interface is designed and implemented to allow users to select the required parameters of the imaging system and the required features of the resultant integral images. The software tool that is based on the developed techniques and employing OpenGL is useful to simulate the imaging systems, tune their parameters before the actual implementation of these systems, and as a result, save time and materials when designing these systems. The introduced techniques and the software tools are faster, more effective, and cheaper original methods to help in optimising both the integral imaging systems and the quality of integral images. These software tools based on the new techniques can be used on a wide range of devices and platforms because these are employing the portable Application Interface OpenGL. With these methods, integral imaging systems are simulated, and optimised; good quality static and animated integral images were created.
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