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This paper examines three areas where the application of functional dependency theory to relational databases has had an impact. These areas are relational views, database translation and logical database design. The paper refines our earlier work on relational views in which the concepts of consistent and updatable views were proposed. In the area of database translation, it identifies six levels of information preserving relational transformations. Finally, a relational database design algorithm is proposed which combines the best features of the classical synthesis and decomposition approaches while avoiding their identified shortcomings. INTRODUCTION This paper shows, that functional dependency theory provides a unified framework for the analysis of several database problems. The paper represents both a synthesis and extension of our earlier work on each of these problems. The first section contains background infor- mation to familiarize the reader with the terminology and concepts of functional dependency theory. In the second section, functional dependencies are used to define the concepts of consistent and updatable views. Basically, a 'consistent view' is one whose interpretation is consistent with that of the underlying database. An 'updatable view' is one whose updates can be translated into appropriate updates of the underlying database. Together, these definitions describe a class of useable views. In section three, six levels of information preserving relational transformations are identified. These levels reflect the different degrees with which transformations preserve the update and retrieval properties of databases. These levels are important since previously many applications have mistakenly assumed that all the information embodied in their database is preserved by the restructuring operations they have employed. Finally, some shortcomings of the classical synthesis and decomposition approaches to relationship database design are identified in the fourth section. A new algorithm is then proposed which combines the best features of these approaches while avoiding their iden- tified shortcomings.

Description d'un traitement de pre-exposition du photoresist de type-AZ depose sur les pastilles qui ameliore le recouvrement apres developpement en inhibant la vitesse de dissolution du photoresist non expose. La pre-exposition consiste a immerger les pastilles recouvertes de photoresist et recuites dans une base faiblement alcaline telle que le developpant 5:1 AZ 351. Explication par la formation d'azoique

Database management systems must provide a concurrency control subsystem to protect database consistency in the presence of concurrent readers and writers. The widely accepted method for realizing such protection in centralized database management systems is through a locking mechanism. The design of a locking mechanism for a relational database management systems presents the developer with a considerable number of new alternatives. This paper discusses some of those alternatives and their tradeoffs. A particular model is then presented which supports these alternatives for relational database management system locking mechanisms. A simulation model is described which was used to provide experimental results investigating these design alternatives. Results from a number of simulation experiments are presented demonstrating the effects on performance realized under different locking mechanism designs and transaction behavior profiles.

This article empirically addresses the dimensional structure of the PRCA‐24. Data from 656 respondents were factor analyzed and yielded inconclusive results for the most appropriate dimensional structure. The single factor solution most commonly espoused was viable; however, four specific characteristics of the data suggested an alternative underlying structure. An analysis of individual subject's patterns of context‐specific subscores revealed an interesting context effect that argues for treating the PRCA‐24 as a four dimensional assessment instrument.

The purpose of this study was to examine the relationship between prioritized rankings of human values among persons who either use or do not use cocaine. Three hundred eighty-three college-aged subjects were given the Wellness Activity Profile, a questionnaire that yielded data on cocaine use and human values. Discriminant analyses indicated that the value profiles of cocaine and non-cocaine users were significantly different for both males and females. The results support the contention that dominant value orientations differ between those using cocaine and those abstaining. Personal values are more important to users, while social values are more important to non-users. Results of the study suggested that prevailing theories informing educational and treatment protocols need to account for value structures that discriminate cocaine users from non-users.

The purpose of this study was to examine the relationship between demographic variables and recreational substance use within the college population. Eight hundred thirty-two college-aged students were given the Wellness Activity Profile, a questionnaire that includes sections yielding demographic and recreational substance usage data. Discriminant analyses of the data indicated that persons using recreational substances differed significantly from non-users. Marijuana users differed from non-users on parental income, high school grade point average, gender, and political orientation, while no demographic differences were found between cocaine users and non-users. Composite substance users differed from non-users on political orientation, parental income, and gender.

Let L = ∑ m = 0 n A m ( x ) D m L = \sum \nolimits _{m = 0}^n {{A_m}(x){D^m}} be a differential operator on ⊕ k L 2 [ 0 , 1 ] { \oplus ^k}{L^2}[0,1] with infinitely differentiable k × k k \times k matrix valued coefficients. Assume that det A n ( x ) ≠ 0 \det \,{A_n}(x) \ne 0 for x ∈ [ 0 , 1 ] x \in [0,1] . The domain of L is the set of k-vector valued functions f such that f ∈ C n − 1 ( [ 0 , 1 ] ) , f ( n − 1 ) f \in {C^{n - 1}}([0,1]),{f^{(n - 1)}} is absolutely continuous on [0, 1] and L f ∈ ⊕ k L 2 [ 0 , 1 ] Lf \in { \oplus ^k}{L^2}[0,1] . Let x 0 ∈ ( 0 , 1 ) {x_0} \in (0,1) . Then there is a neighborhood U ( x 0 ) U({x_0}) containing x 0 {x_0} such that the restrictions of the eigenfunctions of L to U ( x 0 ) U({x_0}) have dense span in ⊕ k L 2 [ U ( x 0 ) ] { \oplus ^k}{L^2}[U({x_0})] . The example L = e − i x d / d x L = {e^{ - ix}}d/dx shows that this is the best possible abstract result.

IN RESEARCH, teaching, and application we have found it convenient for some time now to compute the cost of capital as a weighted average of the costs of the various sources of capital. This entire notion, though, that the true cost of capital can be computed as a weighted average of the component costs has recently been questioned. Reilly and Wecker [9] show us that the conditions under which Solomon [10] first formally developed the weighted-average approach to the cost of capital are rather restrictive. Linke and Kim [6] and Ezzell and Porter [2] argue that these restrictions as to cash-flow patterns are not necessary and that a weighting approach to computing the cost of capital is valid as long as the firm's leverage position is maintained. In addition to these discussions on the general validity of the weighting procedure as a computational device, other arguments have focused on the validity of the particular formulations utilized. Specifically, three interrelated issues have been raised. First, Haley and Schall [3, pp. 298-304] imply and Arditti [1] states flatly that the traditional method of weighting in an after-tax cost of debt is incorrect. Secondly, these same authors feel that once the cost of debt is correctly specified on a beforetax basis, the resultant weighted-average cost of capital, as a function of the firm's capital structure, is not minimized at the point of value maximization. Finally, Ezzell and Porter [2], Arditti [1, p. 1004, footnote 4], and Haley and Schall [3, pp. 304-313] imply that the weighted-average figure utilizing the so-called correctly specified (before-tax) cost of debt may not be usable as a cutoff rate in making investment decisions. It is the contention of this paper that the arguments offered in support of these criticisms are misleading. Most of the confusion generated by this literature results from the failure to recognize that even with a generally accepted definition of the true cost of capital, innumerable specifications of this definition, all equally valid, are possible. Two such specifications of the true cost of capital definition are developed in Section II. For each specification, two corresponding weighted-average costs of capital are formulated. One is less general than the other in the sense that it requires conditions necessary for Modigliani and Miller's [7] capital structure propositions.1 An important conclusion of this section is that as weighted-average formulations of a single definition, there is no basis upon which to identify any

Evaluation, the authors warn, if not carefully planned and implemented, can do more harm than good. In the following article they describe a successful sys tem used to monitor one recent educational innova tion.

Summary.-No relationship was found between isotonic strength and relative isotonic endurance. Additional support was provided by the insignificant results in the analysis of the endurance performance of the three groups based on strength level. Implications for the use of relative isotonic endurance tests in future study of perseverance were discussed. The component of physical fitness known as muscular endurance has been the subject of numerous laboratory investigations. Tests of absolute and relative endurance (2, 4, 14, 15, 18) as well as repeated contractions (10, 13) have been used to measure isometric endurance. The bulk of the laboratory studies of isotonic endurance, however, have included measurement with a type of ergograph (5, 6, 7, 11, 17). The testing procedure with this apparatus has incl~lded a test of strength upon which the weight load for the endurance test was determined. The relative loading procedure for isotonic endurance has usually been based on an isometric strength test. Relationships between isometric strength and relative isotonic endurance have been defined. In light of a recent study by Carlson (3), the absolute value of such relationships is questionable. Acknowledging the observed differences between isometric and isotonic strength, the relationship between isotonic strength and relative isotonic endurance appears to be of greater importance. The purpose of this study, therefore, was to examine the relationship between isotonic strength and relative isotonic endurance. In the ergographic studies by Clarke (5, 6, 7), a test of isometric strength was given to determine the strength of the muscle group to be tested, and the resistance used for the endurance test was a percentage of this strength. Clarke used three-eighths of the strength for the resistance in testing the endurance of the flexor muscles of the forearm and five-eighths of the strength in the studies of the flexor muscles of the arm. These percentages were selected because they induced exhaustion in a relatively short period of time. Different percentages have also been used. Walters, et al. (17) used one-third of the strength of the flexor muscles of the forearm of the preferred arm. McCraw and Burnham (12) used 50% of the isometric strength of the flexor muscles of the upper arm and extensor muscles of the forearm to test isotonic endurance of these muscle groups. Twenty-five per cent of the isometric strength of the extensor muscles of the lower leg and thigh was used by McCraw and Burnham to assess isotonic endurance of these muscle groups. Mathews and Kruse ('11) used

Relative isometric endurance tests of 50, 60, 70, and 80 percent weight loads were used to evaluate the muscular endurance of three groups of male college students. The 47 students were grouped according to level of athletic achievement. Analysis of variance models failed to detect any differences between the endurance of the three groups. Consideration was given to the use of relative endurance tests for evaluating levels of motivation.

Thirty-six male college students served as subjects in a study to determine the reliability of isometric strength assessment of the right elbow flexor muscles by means of an intraclass correlation technique and to estimate reliability one might obtain under similar conditions with different combinations of days and trials. An analysis of variance treatment by subjects design was used to obtain the estimates of error necessary for calculation of the estimate of reliability. Some consideration was given to the effect of degrees of freedom on negative estimates of variance.

Thirty-six male college students served as subjects in a study that examined the relationship between isometric strength and relative isometric endurance of the right forearm flexor muscles. The percentages of maximum isometric strength used for the endurance tests were 30, 45, 60, and 75. Three equal groups were formed based on the strength level of the subjects, and an analysis of variance test was used to determine the existence of significant differences. Significant negative correlations were found between isometric strength and relative isometric endurance. The weak subjects performed significantly better than the strong subjects on the light weight loads, with no difference existing between the endurance performances on the heavy loads.

Simple eigenvalues are shown to be generic in several senses for regular ordinary differential operators.

48 residential students at the Kansas State School for the Deaf were given the Brace Motor Ability Test. Sex had little influence on the levels of performance, while age below 7 yr. yielded significantly lower performance. The extent of hearing loss did not influence the performance.

Introduction. Given a differential operator 1 on Dk L2[0, 1] with compact resolvent, there are associated sequences of projections {Pm}j obtained by integrating the resolvent around circles whose radii tend to infinity. The problem of obtaining an eigenfunction expansion associated with LS is just the problem of showing that for each f E ekL2 [0, 1], limm" 11f Pmf ll = 0. The usual technique for establishing such results involves an analysis of the kernel of the resolvent. If the operator is of high order, or one is dealing with a system of equations, this technique becomes unwieldy. We present an abstract approach to these problems which avoids the usual analysis of the resolvent kernel. Denote the orthogonal sum L2[0, 1] EDl. . . *D L2[0, 1] (k summands) by ?k L2[0, 1]. Let D = d/dx. A trivial but useful fact is that the operator e = iD acting componentwise on ek L2[0, 1] is self-adjoint if equipped with the domain of n-tuples (f1, . .. , f,,) of absolutely continuous functions whose derivatives are in L2[0, 1], and such that (fi, . . . , fn)(O) = (fl, fn)(l). Moreover the spectrum of e is {2iTnln E Z}, and each eigenvalue has multiplicity k. We begin by showing that the distribution of eigenvalues for this example is typical for a large class of unbounded operators. Information about the eigenvalue distribution for higher order differential operators is easily obtained by use of the spectral mapping theorem. Fixing notation, we let 69(e) be the domain of the operator X, and a(fD) its spectrum. Denote by C the complex numbers and by C* the Hilbert space adjoint of the operator C5. Finally we remark that many of the basic facts about ordinary differential operators can be found in Goldberg [5].