Polyethylene has been studied from many different perspectives; a final application property perspective, in which the response of the material to loads is the topic; a micromechanical point of view, in which the macroscopic state of the material is related to its microstructure, e.g., Alvarado (2007), and a chemical point of view in which the molecular structure and the processes that create polyethylene are investigated. This thesis focuses on the mechanical behavior of polyethylene observed from testing and relates the mechanical behavior to the molecular structure of the material. High density polyethylene is a material used in civil engineering applications such as pipes and containers. There are two general modes of failure for polyethylene: ductile failure that happens at relatively large stresses (up to 200MPa) and in short amount of time, and brittle failure that occurs when a much lower stress is sustained over a long period of time (Cheng 2008). Other than these two modes of failure, excessive deformation of the material that is usually caused by creep is also to be avoided. This thesis studies the relationship between short-term and long-term creep of polyethylene and its molecular structure. In this work three types of mechanical tests were performed on six samples of polyethylene. The existing models that prescribe the constitutive behavior of the material were then critically evaluated against the observed data. Furthermore the molecular properties of the samples that had been obtained from previous research by Cheng (2008) were compared against the mechanical behavior observed from testing in order to assess what molecular properties are important in determining the mechanical behavior of polyethylene. This information can also help polyethylene designers to produce longer lasting material, or a material that has high stiffness, by knowing what molecular properties to control and optimize.

This dissertation presents different aspects of long-term contract for product service system (PSS); also different issues that companies are dealt for implementation of PSS. The study consists of literature review for understanding factors which can affect long-term PSS contracts. Different generic categories of green business models which are used in PSS contracts have been addressed and in addition, various models of contracts for PSS in industries have been identified too. The important factors which can influence these types of contracts are categorized in six major aspects organizational, social, economic, technological, legal and environmental. Each of these factors separately has been analyzed by reviewing related literature. Moreover a general evaluation about effect of each factor in other influential factors has been presented. In respect of long duration of contract, the rate of uncertainty is higher than traditional method of buying a product. Here, problems which are related to each of these factors have been addressed. Moreover, different approaches of companies for these problems have been discussed which these solutions can be useful for other providers in similar situation.

Polyethylene has been studied from many different perspectives; a final application property perspective, in which the response of the material to loads is the topic; a micromechanical point of view, in which the macroscopic state of the material is related to its microstructure, e.g., Alvarado (2007), and a chemical point of view in which the molecular structure and the processes that create polyethylene are investigated. This thesis focuses on the mechanical behavior of polyethylene observed from testing and relates the mechanical behavior to the molecular structure of the material. High density polyethylene is a material used in civil engineering applications such as pipes and containers. There are two general modes of failure for polyethylene: ductile failure that happens at relatively large stresses (up to 200MPa) and in short amount of time, and brittle failure that occurs when a much lower stress is sustained over a long period of time (Cheng 2008). Other than these two modes of failure, excessive deformation of the material that is usually caused by creep is also to be avoided. This thesis studies the relationship between short-term and long-term creep of polyethylene and its molecular structure. In this work three types of mechanical tests were performed on six samples of polyethylene. The existing models that prescribe the constitutive behavior of the material were then critically evaluated against the observed data. Furthermore the molecular properties of the samples that had been obtained from previous research by Cheng (2008) were compared against the mechanical behavior observed from testing in order to assess what molecular properties are important in determining the mechanical behavior of polyethylene. This information can also help polyethylene designers to produce longer lasting material, or a material that has high stiffness, by knowing what molecular properties to control and optimize.

The Chronic Pain Center (CPC) in Saskatoon offers a multidisciplinary treatment program whose goals are to facilitate improved coping skills, function and well-being, and to promote self-reliant lifestyles. They have documented a statistically significant improvement on several measures of physical and social functioning at the completion of the six week program, but to date have no formal evaluation of the long term effects.<p/> The purpose of this study was to re-evaluate the CPC clients (treatment group) at least one year following their completion of the treatment program to determine if they had maintained those improvements and also to compare them to the group of clients (control group) who underwent initial multidisciplinary assessment at the Centre, but did not attend the six week treatment program. Evaluation by mail out questionnaires assessed several important aspects of chronic pain. A 34% response rate resulted in 142 participants for this study.<p/> Data analyses involved a multi-stage process of univariate, bivariate and multivariate analyses. For the first goal, evaluating changes in the treatment group over time, the outcome variables considered had been administered at three points in time: admission to the CPC program, discharge from the six week program, and at study follow-up. For the second goal, the treatment and control groups were compared at one point in time; the study follow-up.<p/> The study demonstrated that the scores on all outcome variables used in the follow-up study improved significantly from the time of assessment to the time of discharge for the clients who attended the CPC treatment program. These improvements declined over time, but remained significantly improved from the admission scores. (Wilks Ë=.501, F(1,48)=4.788, p=.000) However, the study was unable to demonstrate any significant differences between the treatment and control groups on any of the outcome measures at the time of the study follow-up.(Wilks Ë=.930, F (1,107) = 1.014, p=.430) There were several limitations to this study, including the use of a non-randomized control group and the method of recruitment, which may have introduced bias into the study and affected the ability to effectively explain this finding.<p/>

This thesis examines vegetation community change at two temporal scales in the Piedmont of North Carolina. Using long-term plots in the Duke Forest, I examine decadal-scale changes in community composition of the forest understory and shed light on the potential drivers of that change. Using historical data from colonial survey records, I study presettlement forest communities of the Piedmont and attempt to reconstruct Piedmont forests as they may have been in the time before European arrival. The pattern of successional change in southeastern United States Piedmont forests has been assumed from chronosequence studies over the last half century. However, these assumptions for forest understory herb-layer populations and communities have not been tested using long term data sets. Using permanently marked plots in the Duke Forest (Durham, NC, USA) re-censused after a 23 year time step, species richness and community changes at 25m2 and 1000m2 scales are examined. I look at changes across life forms and examine these changes in relation to measured stand and environmental factors. Although total species richness stayed relatively constant through the 23 year step, herb richness declined with a concomitant increase in woody richness. Plot composition change was remarkably consistent and this change was not correlated to any measured stand or environmental factors. These community-level changes are consistent with previously reported changes in the understories of hardwood dominated stands in the Duke Forest, suggesting that landscape scale drivers may be more important than within-stand successional processes in patterning herbaceous communities at this time. Combined with growing evidence from other studies, this work indicates that forests in the temperate region may be experiencing changes different from those predicted by successional chronosequence studies. It indicates that one of the primary drivers of this change is the explosive growth of deer populations in the last two decades. Witness trees recorded in historical surveys have been used to reconstruct presettlement vegetation in many parts of North America, leading to a better understanding of vegetation patterns before the effects of Europeans. For some parts of North America, Government Land Office records make the process of reconstructing vegetation patterns easier - thus more is known about these areas. Because of the unique and unplanned nature of settlement in the southeastern U.S., less is known about the presettlement vegetation in this area of the country. Using a reconstructed cadastral map of a section of the North Carolina Piedmont, I was able to plot the positions of trees on the historical landscape. These data were then used to understand and reconstruct the composition of presettlement forests. Although the vegetation of some areas of the Piedmont is similar to what was expected, I find significant differences with the expected presettlement composition. In particular, pine species were common in some areas and rare in others, indicating that different disturbance regimes were active on the landscape. / Dissertation

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I examine the market reaction to merger announcements and the long-term post-merger stock price performance of newly merged firms. For a sample of 484 acquiring firms completing mergers between 1993 and 2000, the average value-weighted abnormal announcement date return (market-adjusted) is a statistically significant -1.02%. On average, this reaction is more negative for firms with "good governance." Specifically, a governance index comprised of three governance variables is significantly negative in a multivariate regression of announcement date abnormal returns. Comp is the percentage of CEO salary consisting of equity incentives (including stock options and restricted stock grants), InsideOwn is the percentage of the firm owned by officers and directors, and InstOwn is the percentage of the firm owned by large outside block shareholders. Value-weighted calendar-time portfolios consisting of the full sample of acquirers exhibit significant abnormal returns of 9.12%, 33.84% and 55.8% for the 12, 36 and 60 months following the merger, respectively. This overperformance is limited to the value-weighted portfolios. There is calendar-time evidence of abnormal performance for some subsamples on a risk adjusted basis. However, when compared to a control group, abnormal performance is limited to large glamour acquirers on a 12-month horizon, large cash acquirers on a 36 and 60-month horizon, and small focusing acquirers on a 60-month horizon. Multivariate analysis of long-run returns reveals that use of equity and corporate diversification are associated with lower post-merger performance. With regard to governance and long-run stock returns, there is also evidence that suggests higher levels of incentive compensation for CEOs is associated with more successful merger transactions for long-term investors.

Lignocellulosic biomass (e.g., poplar wood) provides a unique and sustainable resource for environmentally safe organic fuels and chemicals. The core of this study is the pretreatment step involved in bioconversion processes. Pretreatment is required to realize high yields vital to commercial success. The focus of the pretreatment step is to methodically change key features of the biomass to favor enzymatic hydrolysis. This work assesses the compositional changes due to oxidative and non-oxidative longterm lime pretreatment of poplar wood (up to 4 weeks of pretreatment) at mild temperatures (25ºC to 65ºC), and their effect on the enzymatic yield of glucan and xylan. The most important pretreatment yield of lignin was 54 g lignin remaining/100 g lignin in raw biomass, and was accomplished for 4-week lime pretreatment at 65ºC in oxidative conditions. The corresponding pretreatment yields of glucan and xylan were 85.9 g glucan recovered/100 g glucan in raw biomass and 80.2 g xylan recovered/100 g xylan in raw biomass respectively. For poplar wood oxidatively pretreated with lime for 4 weeks at 65ºC and enzymatically hydrolyzed with an enzyme loading of 15 FPU/g glucan in raw biomass during a 3-day period, the best overall yields of glucan and xylan, were 80.7 g glucan hydrolyzed/100 g glucan in raw biomass and 66.9 g xylan hydrolyzed/100 g xylan in raw biomass respectively. The corresponding hydrolysis yields were 94.0 g glucan hydrolyzed/100 g glucan in treated biomass and 83.5 g xylan hydrolyzed/100 g xylan in treated biomass respectively. Because there is a previous study of long-term lime pretreatment of corn stover (Kim, 2004), the data obtained in this work show the effect of using woody lignocellulose as substrate. From the comparison, resulted that in the case of poplar wood oxidatively pretreated at 65ºC for 4 weeks, less lignin was removed and more carbohydrates were solubilized, however the hydrolysis yield of glucan was almost equal and the hydrolysis yield of xylan was higher than the reported by Kim for corn stover oxidatively pretreated at 55ºC for 4 weeks. The overall yield of glucan resulted lower in the case of poplar wood because of the lower pretreatment yield of glucan. Thus, it is important to complete the mass balances including an analysis on the pretreatment liquor to determine if the solubilized glucan was degraded.

This study is to discuss the services of public ¡§Sheng Mu¡¨ Time Bank in Taiwan. Time Bank was developed as a way of providing non-medical services for older people ¡V helping them to stay in the own homes, keep hospital appointments and stay healthy. Unlike traditional services of volunteers, Time Bank enables volunteers to earn and pay time credits for giving and receiving non-medical services.That is to say, Time Bank is a community plan for mutual contribution. Everyone can give and everyone can get. ¡§Sheng Mu¡¨ Time Bank was established by Taiwan governmental instituation in 1998. Since ¡§Sheng Mu¡¨ Time Bank has over ten years of experience in promoting this program, there must be some difficults and problems during promoting process.Thus, the first purpose of this study is to understand what Time Bank is and how it works. Besides, this study is to understand how do managers of volunteers and volunteers think about Time Bank. Finally, this study is to find out the difficults and problems in promoting this program.

Under the well developed economy and the medical, aged population brings up the related medical service demands. In the future, the service quality is a key to determines the life of long-term-care institutes. The purpose of this study to address the relationships among the product factors by which people make a decision. Besides, the construction of what degrees of people emphasis on them is also explored as well. Based on the above, ten nights were used to collect 1097 effective samples by making phone calls. After analysis by statistics software, the conclusions are as below, 1. Men pay more attention to opinions of medical professionals than women. In the inspections of reference group, opinions of relatives & friends (46%) hardly differ from them of medical professionals (47%). However, It was found that man intends to refer more of medical professionals than women, and women put more emphasis on them relatives and friends than men in the cross analysis of gender-reference group. 2. The better educated people put more emphasis on quality of institutes. We can expect the better educated people earn more incomes, and they usually can accept the more expenses which are set as 25 thousands for each month. And this also highlights they concern the service quality than other groups even they¡¦re charged more. 3. It determines the service quality whether an institute has medical professionals or not. This highlights the expectations and trust of people to an institute with medical professionals. Under the trends of diseases changes of the older, the daily care of them is not only included, but also long term tracing or inspection on diseases is necessary. 4. In the past affections on filial piety of China, people thought that distances between the institute and home will be a key factor to choose for visit and take over the older easier. However, People do not care how far from home, when an institute with good service quality can also provide better prices. Key words: Kaohsiung Area, Long Term Care Institute