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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.
71

Investigation of Factors Affecting the Emulsification of Skin Creams / Undersökning av faktorer som påverkar emulgeringen av hudkrämer

Bodell, Linnéa January 2019 (has links)
Skin creams are one of Sky Resources key products, they are produced as an oil-in-water(O/W) emulsion. In order to form an emulsion the oil and water needs to be able to mixtogether, for that to happen the oil and water droplets have to be broken up into very smalldroplets (colloids). There is a certain quality difference between the products from the research and developmentdepartment and the production department. The skin creams have been made through a given recipe, which contains a number of chemicalformulas. Tests have been preformed and the results have been examined. The creams werefirst made in the research and development department’s laboratory and then that small scaleproduction was taken to big scale production in the production department. The results havebeen documented and the parameters that have been examined are speed, temperature and timeto see how they affect the viscosity of the creams. A factorial experiment with three factors has been made. The factors are the time the skincream is homogenized, at what speed the cream is homogenized and at what temperature thephases are when the homogenizing is started. That gives a total of 8 creams from thelaboratory level. The viscosity of the skin creams have been measured after 10 minutes, 24 hours, 48 hours and1 week to see how it is increasing with time and if it is increasing at all or perhaps decreasing.After 1 week the creams were also studied under a microscope to see how successful theemulsions were with different factors. The fourth cream was the only cream from the laboratory that had a successful emulsion andstabilized viscosity. So the factors that are brought from laboratory to production is highhomogenization time, high homogenization speed and low temperature. Two differenthomogenizers were tried in production. The factor that affects the viscosity the most seems to be the temperature. After these tests,there is still a difference between the products from the research and development departmentand the production department even with the lower temperatures on the oil and water phases.The second cream from production and cream 4 from the laboratory show the smallest qualitydifference. More tests need to be done in the production department with differenthomogenization speed and time with the lower temperature to establish the result. / Hudkrämer är en av Sky Resources viktigaste produkter, de produceras som en olja-i-vattenemulsion(O/W). För att bilda en emulsion måste oljan och vattnet kunna blandas och för attdet ska hända måste olje- och vattendropparna brytas upp i mycket små droppar (kolloider). Det finns en viss kvalitetsskillnad mellan produkterna från forsknings- ochutvecklingsavdelningen och produktionsavdelningen. Hudkrämerna har gjorts genom ett givet recept, som innehåller ett antal kemiska ingredienser. Tester har utformats och resultaten har undersökts. Krämerna gjordes först i forsknings- ochutvecklingsavdelningen laboratorium och sedan togs den småskaliga produktionen tillstorskalig produktion i produktionsavdelningen. Resultaten har dokumenterats ochparametrarna som har undersökts är hastighet, temperatur och tid för att se hur de påverkarviskositeten hos krämerna. Ett faktorförsök med tre faktorer har gjorts. Faktorerna som använts är den tid hudkrämenhomogeniseras, i vilken hastighet krämen homogeniseras och vid vilken temperatur faserna ärnär homogeniseringen startas. Det ger totalt 8 krämer från laboratorienivån. Viskositeten hos hudkrämerna mättes efter 10 minuter, 24 timmar, 48 timmar och 1 vecka föratt se hur den ändras med tiden. Efter 1 vecka studerades också krämerna under ett mikroskopför att se hur lyckad emulsionerna var med olika faktorer. Den fjärde krämen var den enda krämen från laboratoriet som hade en lyckad emulsion och enstabil viskositet. Så de faktorer som tas från laboratorium till produktion är höghomogeniseringstid, hög homogeniseringshastighet och låg temperatur. Försök gjordes i tvåhomogenisatorer i produktionen. Den faktor som påverkar viskositeten mest är temperaturen. Efter dessa tester finns det dockfortfarande skillnader mellan produkterna från forsknings- och utvecklingsavdelningen ochproduktionsavdelningen, även med de lägre temperaturerna på olje- och vattenfaserna. Denandra krämen från produktion och kräm 4 från laboratoriet visar den minstakvalitetsskillnaden. Fler test måste göras i produktionsavdelningen med olikahomogeniseringshastigheter och tider med den lägre temperaturen för att fastställa resultatet.
72

Factorial Ecology of Residential Mobility and Migration, 1956-61, Hamilton, Ontario

Heins, Diana Margaret Jean 11 1900 (has links)
<p> This study investigates variables associated with residential mobility and migration at the ecological level. The aim of the study is to test the application of factor analysis to a more specific subject than the description of the whole urban structure. </p> <p> Theoretical formulations about urban growth, urban ecology and mobility are examined, together with empirical research in these fields, to determine variables considered to be associated with changes in residence. The indicators of variables chosen for analysis are from census data and city reports, and each census tract of the chosen urban area is assigned a value for each indicator. The area selected for the study is the Hamilton Metropolitan Area, Ontario. </p> <p> The results of the analysis reveal that most of the variation in the variables is accounted for by two factors: dwelling type and household composition, and economic status. These are the same factors which have been identified in factorial ecologies of geaeral urban structure. </p> The remaining factors are more associated with mobility, and reveal that different origins of movers and migrants are associated with different characteristics and geographical distributions. The hypotheses concerning the relationships with age, population growth and distance from the city centre are supported by the analysis, and the size and direction of movement is generally as expected. However, the hypothesis of increasing economic status with increasing distance migrated is not confirmed: migrants from abroad and different provinces tend to migrate to areas or lower economic status than migrants from Ontario or from the Hamilton metropolitan fringe. </p> <p> This study recognises the limitations of a factorial ecology of residential mobility. Particular care should be exercised in the selection of variables and measures of these variables. Factorial ecology is a descriptive tool, and further analysis of apparent association between variables should be undertaken to determine their statistical significance. </p> <p> The study emphasises the contribution of factorial ecology to the description of areal associations of more specific subjects such as residential mobility, and possibly for other social phenomena. As such, it provides a means for parsimonious description of aspects of urban social geography. </p> / Thesis / Master of Arts (MA)
73

The relationship between counseling supervisee attachment orientation and supervision working alliance rapport

Renfro-Michel, Edina Lynn 13 May 2006 (has links)
This study examined the relationship between supervisee attachment orientation, rapport of the supervision working alliance over time, the change of supervisee attachment orientation, and the perceived impact of supervision on the lives of the supervisees. Participants were 117 master?s level counseling student at the entry (34), practicum (45), and internship (38) levels, counseling clients with supervision. This study used the Relationship Questionnaire and the Rapport score from the Supervision Working Alliance Inventory. Data was collected via e-mail at the beginning, middle, and end of the semester. Data was examined using Two-Way Factorial ANOVAs, Bowker Tests, and Chi-Square Tests. There were statistically significant changes in attachment orientation over time, and a statistically significant relationship between working alliance rapport scores and supervisee attachment. A change in attachment from preoccupied and fearful toward secure and dismissing orientations occurred. These findings may indicate the importance of considering attachment in the supervision relationship.
74

Diophantine Equations Involving Arithmetic Functions of Factorials

Baczkowski, Daniel M. 12 July 2004 (has links)
No description available.
75

An expert system for designing statistical experiments

Shraim, Mustafa S. January 1989 (has links)
No description available.
76

Choice Experiments for Estimating Main Effects and Interactions

Chen, Jing January 2010 (has links)
Choice-based conjoint experiments are used when choice alternatives can be described in terms of attributes. The objective is to infer the value that respondents attach to attribute levels. This method involves the design of profiles on the basis of attributes specified at certain levels. Respondents are presented sets of profiles and asked to select the one they consider best. Choice sets with no dominating or dominated profiles are called Pareto optimal, and these Pareto optimal choice sets are provided to respondents. However, if choice sets have too many profiles, they may be difficult to implement. Therefore, we provide strategies for reducing the number of profiles in choice sets. We consider situations where only a subset of interactions is of interest, and obtain connected main effects plans with smaller choice sets for 2^n and 3^n designs that are capable of estimating subsets of interactions inclusive of one specific factor. We also provide plans for estimating all main effects and one two-way interaction for mixed level designs. Next, we examine the relationship between certain Pareto Optimal choice sets and g-designs. Finally, we obtain connected main effects plans with smaller choice sets for estimating different subsets of interactions, not inclusive of one specific factor. / Statistics
77

On the construction of balanced and partially balanced factorial experiments

Chang, Cheng-Tao January 1982 (has links)
Satisfactory systems of confounding for symmetrical factorial experiments can be constructed oy the familiar methods, using the. theory of Galois fields. Although these methods can be extended to asymmetrical factorial experiments· (White and Hultquist, 1965; Raktoe, 1969) the actual construction of designs becomes much mor:e complicated for the general case and does not always lead to satisfactory plans. A different approach to this problem is to consider balanced factorial experiments (BFE), due to Shah (1958, 1960). Such BFE have a one-to-one relationship to EGD-PBIB designs given by Hinkelmann (1964). The problem of constructing BFE is then equivalent to constructing EGD-PBIB designs. A new method is proposed here to construct such designs. This method is based upon the so-called (1,1, ...,1)th-associate matrix and the operations symbolic direct product (SDP), generalized symbolic direct product (GSDP), symbolic direct multiplication (SDM), and generalized symbolic direct multiplication (GSDM). Let A₁ , A₂, ... , A<sub>n</sub> be n factors in a factorial experiment, with A<sub>i</sub> having t<sub>i</sub> levels (i = 1, 2, ... , n). It is shown that an EGD-PBIB design with blocks of size t<sub>i</sub> can be constructed, provided that t<sub>i</sub>ᵢ ≠ max ( t₁ , t₂, . . . , t<sub>n</sub> ). This method is more general and more flexible than the method of Aggarwal (1974) in that any two treatment combinations can be γ-th associates where γ has at least two unity components, and it can be shown the number of possible candidates for such is 2<sup>n-i l</sup> -1 for blocks of size t<sub>i</sub> (i = 1, 2, .. , n -1), where t₁ < t₂ <...< t<sub>n</sub>. This method is also more general than the Kronecker product method due to Vartak (1955}. Two types of PBIB designs· are used for reducing the numbers of associa,te classes in EGD-PBIB designs. When the t<sub>i</sub> (i = 1, 2, ... , n) are equal, then some EGD-PBIB designs can be reduced to a hypercubic design. The EGD-PBIB designs with block size π [below jεA] t<sub>j</sub>, where A is an arbitrary subset of the set {1, 2, ... , n} can be reduced to newly introduced F<sub>A</sub><sup>(n)</sup>-type PBIR designs. Since BFE results very often in designs with a large number of blocks, the notion of partial balanced factorial experiment (PBFE) has been introduced. It is investigated how such designs can be constructed and related to PBIB-designs similar to that between BFE and EGD-PBIB designs. Two new types of PBIB designs have been introduced in this context. / Ph. D.
78

The Factoradic Integers

Brinsfield, Joshua Sol 24 June 2016 (has links)
The arithmetic progressions under addition and composition satisfy the usual rules of arithmetic with a modified distributive law. The basic algebra of such mathematical structures is examined; this leads to the consideration of the integers as a metric space under the "factoradic metric", i.e., the integers equipped with a distance function defined by d(n,m)=1/N!, where N is the largest positive integer such that N! divides n-m. Via the process of metric completion, the integers are then extended to a larger set of numbers, the factoradic integers. The properties of the factoradic integers are developed in detail, with particular attention to prime factorization, exponentiation, infinite series, and continuous functions, as well as to polynomials and their extensions. The structure of the factoradic integers is highly dependent upon the distribution of the prime numbers and relates to various topics in algebra, number theory, and non-standard analysis. / Master of Science
79

A graphical comparison of designs for response optimization based on slope estimation

Hockman, Kimberly Kearns January 1989 (has links)
The response surface problem is two-fold: to predict values of the response, and to optimize the response. Slope estimation criteria are well suited for the optimization problem. Response prediction capability has been assessed by plotting the average, maximum, and minimum prediction variances on the surface of spheres with radii ranging across the region of interest. Average and maximum prediction bias plots have recently been added to the spherical criteria. Combined with the prediction variance, a graphical MSE criterion results. This research extends these ideas to the slope estimation objective. A direct relationship between precise slope estimation and the ability to pinpoint the location of the optimum is developed, resulting in a general slope variance measure related to E-optimality in slope estimation. A more specific slope variance measure is defined and analyzed for use in evaluating standard response surface (RS) designs,where slopes parallel to the factor axes are estimated with equal precision. Standard second order RS designs are then studied in light of the prediction and optimization goal distinction. Designs which perform well for prediction of the response do not necessarily estimate the slope precisely. A spherical measure of bias in slope estimation is developed and used to measure slope bias due to model misspecification and due to the presence of outliers. A study of augmenting saturated orthogonal arrays of strength two to detect lack of fit is included as an application of a combined squared bias and variance measure of MSE in slope. A study of the designs recommended for precise slope estimation in their robustness to outliers and to missing observations is conducted using the slope bias and general slope variance measures, respectively. / Ph. D.
80

Economic expansible-contractible sequential factorial designs for exploratory experiments

Hilow, Hisham January 1985 (has links)
Sequential experimentation, especially for factorial treatment structures, becomes important when one or more of the following, conditions exist: observations become available quickly, observations are costly to obtain, experimental results need to be evaluated quickly, adjustments in experimental set-up may be desirable, a quick screening of the importance of various factors is important. The designs discussed in this study are suitable for these situations. Two approaches to sequential factorial experimentation are considered: one-run-at-a-time (ORAT) plans and one-block-at-a-time (OBAT) plans. For 2ⁿ experiments, saturated non-orthogonal 2ᵥⁿ fractions to be carried out as ORAT plans are reported. In such ORAT plans, only one factor level is changed between any two successive runs. Such plans are useful and economical for situations in which it is costly to change simultaneously more than one factor level at a given time. The estimable effects and the alias structure after each run have been provided. Formulas for the estimates of main-effects and two-factor interactions have been derived. Such formulas can be used for assessing the significance of their estimates. For 3<sup>m</sup> and 2ⁿ3<sup>m</sup> experiments, Webb's (1965) saturated non-orthogonal expansible-contractible <0, 1, 2> - 2ᵥⁿ designs have been generalized and new saturated non-orthogonal expansible-contractible 3ᵥ<sup>m</sup> and 2ⁿ3ᵥ<sup>m</sup> designs have been reported. Based on these 2ᵥⁿ, 3ᵥ<sup>m</sup> and 2ⁿ3ᵥ<sup>m</sup> designs, we have reported new OBAT 2ᵥⁿ, 3ᵥ<sup>m</sup> and 2ⁿ3ᵥ<sup>m</sup> plans which will eventually lead to the estimation of all main-effects and all two-factor interactions. The OBAT 2ⁿ, 3<sup>m</sup> and 2ⁿ3<sup>m</sup> plans have been constructed according to two strategies: Strategy I OBAT plans are carried out in blocks of very small sizes, i.e. 2 and 3, and factor effects are estimated one at a time whereas Strategy II OBAT plans involve larger block sizes where factors are assumed to fall into disjoint sets and each block investigates the effects of the factors of a particular set. Strategy I OBAT plans are appropriate when severe time trends in the response may be present. Formulas for estimates of main-effects and two-factor interactions at the various stages of strategy I OBAT 2ⁿ, 3<sup>m</sup> and 2ⁿ3<sup>m</sup> plans are reported. / Ph. D.

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