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The primary objective of this research was to assess and to model the hygrothermal properties of CLT panels made from three distinct combinations of spruce lumber and laminated strand lumber (LSL). The hygrothermal performance of these materials both individually and in conjunction in CLT has not been investigated before and is an important indicator of CLT building wall performance. CLT panels consisting of spruce as a face layer absorbed moisture more rapidly when that face layer was exposed to higher moisture concentration compared to CLT panels consisting of LSL as a face layer. The accumulation of moisture between layers increased with placement of the LSL as a core layer. Based on the smaller diffusion coefficient, moisture transport through the CLT panels made of LSL was slower. Modelling with a finite elementbased program showed that the temperature in the panels when exposed to a severe gradient equilibrated within two days, as shown by both experimental and simulated results. For moisture transfer, the diffusion coefficient variation with moisture content and temperature based on the Arrhenius equation produced simulation results in agreement with experimental results but the moisture transfer was much slower than the heat transfer. [ABSTRACT FROM AUTHOR]

A numerical experiment was performed in order to examine the ability of multiple Monte Carlo realizations of a numerical model to reproduce the risk from a hypothetically known waste disposal situation. In the analysis, the risk was summarized by several risk metrics that could be chosen by a regulatory agency to set a risk standard. In the numerical experiment, the parameters in the numerical model are systematically varied to adjust bias (conservative or nonconservative) and to increase uncertainty relative to the hypothetically known future. The influence of parameter bias and uncertainty on the accuracy of each risk metric in predicting the nominal risk was evaluated and presented graphically. These analyses concluded that the peak-of-the-mean metric provides the least stable and least accurate risk predictions, whereas the cumulative release metric and mean of the peaks are more stable and accurate. The peak-of-the-mean and peak-of-the-median metrics exhibit risk dilution (i.e., a decrease in the predicted risk with increased uncertainty) and tend to underpredict risk. Additionally, these results illustrated how risk predictions that are made using what may be considered "conservative" assumptions can be moved in a direction that may or may not be expected or intended. Simulation relative to a hypothetical future (i.e., the nominal case) provides insight into the numerical behavior and potential accuracy of our risk assessment tools and potential issues with setting regulatory standards. [ABSTRACT FROM AUTHOR]

This research assessed the feasibility of using a neural network to detect low levels of damage in small samples of medium density fiberboard (MDF). The neural network was a three-layer back-propagation network. The undamaged stress wave frequency spectrum patterns were trained by the neural network. The trained patterns were then compared to stress waves patterns taken from MDF samples loaded to various percentages of their estimated failure load. In this experiment, if an application load is below the proportional limit, a small change in wave patterns occurs. The neural network has the unique ability to train data to recognize spectral patterns and has been used with success for the detection of structural damage. [ABSTRACT FROM AUTHOR]

Underground concrete vaults have been and are planned to be used to store contaminated materials, such as hazardous materials and radioactive waste, over long periods of time. To protect humans from exposure to the contamination, the key to this long-term storage is immobilization achieved through designing concrete vaults with enhanced hydraulic performance. This paper evaluates concrete vault design parameters including properties of soil layers surrounding the vault, vault size, slope of the vault roof, and the amount of concrete degradation under various infiltration rates. A numerical model that estimates the flow of water through the vault is used as the computer simulation tool. Conclusions from the modeling simulations are that clay layers, including sand and loam layers forming a capillary barrier and placed adjacent to the vault concrete, were found to have a better hydraulic performance. Smaller vault sizes result in lower seepage through the vault and suggest a scale effect. Roof slope has a relatively small influence on hydraulic performance. [ABSTRACT FROM AUTHOR]

Estimates the prevalence of elder caregiving among the work force population. Characteristics of elder caregivers and care recipients; Study sampling methodologic characteristics; Study response rate and reported elder care prevalence.

SUMMARY On the basis of a "value-attitude" interpretation of the esteem for least preferred co-worker (LPC) score, it was hypothesized that task-oriented (low-LPC) persons are more extreme in attitudes toward both positive and negative attitude objects than are relationship-oriented (high-LPC) persons. Attitudes of 51 male and 59 female undergraduates were measured toward four stimulus objects on 22-item semantic differential scales: self, best friend, psychology professor, and most disliked student. ALPC x Stimulus Person interaction provided significant support for the hypothesis when Total LPC scores (p < .002) or Task LPC factor scores (p < .001) were used to classify task-oriented and relationship-oriented Ss, but not when the Social LPC factor scores were used for this purpose. [ABSTRACT FROM AUTHOR]

Evaluates the research on follower satisfaction based on the score of the leader on the least preferred co-worker (LPC) scale of Fiedler. Measurement of leadership effectiveness; Application of the hierarchy and value-attitude interpretations of LPC; Impact of follower satisfaction on leadership effectiveness.

Discusses the impact of leader sex roles and follower attitudes toward women on group performance and group member perceptions. Use of Post-task questionnaire in determining leader behavior; Determinant of group process; Empirical criteria of effective leadership.

Moderated regression analyses are used to assess the degree to which indirect indicators of job importance moderate the relationship between job satisfaction and life satisfaction. The 1971 Quality of American Life Survey (N = 2,164) and the 1972-1973 Quality of Employment Survey (N = 1,496) provide two large nationwide probability sample data sets for these secondary analyses. It is hypothesized that the strength of the job satisfaction-life satisfaction relationship is positively related to job importance. Contrary to this hypothesis, respondents whose jobs were expected to be more important do not have substantially stronger job satisfaction-life satisfaction relationships than respondents whose jobs were expected to be less important. The zero-order job satisfaction-life satisfaction correlations in both samples are stronger than expected (r = .48 and r = .49). Discussion focuses on the conceptual implications of the failure to find substantial moderator effects. Locke's (1969) theory of the implicit role of importance in determining satisfaction is invoked to explain the obtained pattern of results. [ABSTRACT FROM AUTHOR]

After briefly discussing the prominence, basic substance, and history of Fiedler's contingency model of leadership effectiveness, four issues crucial to the current status and future development of the model were considered: (a) the form of the contingent relationship actually constituting the model; (b) the need for direct measurement of situational favorableness; (c) the problem of classifying results from evidential validation studies; and (d) the need for process measurement in studies evaluating organizational applications of the model. Conclusions were offered concerning the contribution already made by the contingency model to leadership research and key directions for future research involving the model. [ABSTRACT FROM AUTHOR]

In a laboratory study of 72 four-person ad-hoc groups of West Point cadets, the evidential validity of Fiedler's contingency model was tested for female and male leaders. For leaders of both sexes, the relationships between leader LPC scores and objective measures of group task performance were statistically significant in several cases. Difficulties in interpreting the degree to which these results support predictions of the model suggested the need to develop direct measures of situational favorableness. Such a measurement system would allow researchers to avoid reliance on assumptions that cannot be subjected to empirical verification. Conclusions called for further development of the contingency model for both female and male leaders. [ABSTRACT FROM AUTHOR]

This study explored the meaning of Fiedler's (1967) LPC. scale through direct examination of respondents' reported experiences with their least preferred co-workers and reactions to the LPC scale. An in-depth interview focused on specific incidents in which the co-worker proved troublesome. An attitude-value perspective of the task versus interpersonal interpretation of the LPC provided a framework for content analysis of these data. The complexity of the link between attitudes and behavior is discussed. [ABSTRACT FROM AUTHOR]

After a brief discussion of the nature and importance of work, this article reviews empirical research that relates satisfaction with work to satisfaction with life. The review covers more than 350 job-satisfaction/life-satisfaction relationships reported in 23 studies that vary widely in terms of the sample, instrumentation, and date of survey. For more than 90% of the cases, the direction of this relationship is positive; and none of the scattered negative relationships is statistically reliable. The magnitude of the reported zero-order relationship between job satisfaction and overall life satisfaction is typically modest, with correlations mostly in the mid-.30's for males and mid-.20's for females. The typical job-satisfaction/life-satisfaction correlation drops to the low teens when specific facets of life satisfaction, such as marital or leisure satisfaction, are used instead of overall life satisfaction. Discussion of these findings focuses on conceptual and methodological concerns at the more general level of the relationship between work and nonwork. [ABSTRACT FROM AUTHOR]

In the northeastern United States, eastern white pine (Pinus strobus L.) is a leading species in the forest products industry. The native pathogen Caliciopsis pinea Peck is associated with Caliciopsis canker of white pine, with symptoms including excessive resin production and cankers. This study processed 28.0 m3 of white pine lumber to (i) quantify losses resulting from Caliciopsis canker, (ii) assess how damage varies between Caliciopsis canker symptom severity and thinning, and (iii) quantify economic loss resulting from damage. Caliciopsis canker damage was present in 37% of lumber, yet only 10% was downgraded due to canker damage. Of the downgraded lumber, the vast majority (77%) lost one grade. Additionally, severely symptomatic trees consistently had more damage, and their lumber was more likely to be downgraded than trees with low symptom severity. Caliciopsis canker damage resulted in average revenue losses of 2.3%, yet much of the sampled lumber had other, more significant damage that resulted in downgrade: highly symptomatic trees averaged 63% of the revenue of low or asymptomatic trees. Caliciopsis canker, therefore, can be used as an indicator of poor quality trees. We recommend thinning Caliciopsis canker symptomatic trees to meet low-density stocking guidelines, which may minimize revenue loss while simultaneously minimizing stress to residual stock. [ABSTRACT FROM AUTHOR]

The range-of-affect hypothesis (Locke, 1976) argues that facet importance is a key determinant of the level of satisfaction associated with any particular job facet. A larger range of facet satisfaction is expected for workers placing greater personal importance on a job facet (i.e., greater satisfaction with favorable conditions and greater dissatisfaction with unfavorable conditions). Although this hypothesis has been supported by studies using American samples, research is needed to assess its generalizability in other countries. This study takes a first step in that direction by finding support for the hypothesis in a sample of South African employees. In addition, unlike previous research, our study uses two alternative methods to examine the range-of-affect hypothesis. Practical implications and research directions are discussed. [ABSTRACT FROM AUTHOR]