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AbstractAn algorithm is presented to gain postoptimality data about the family of nonlinear pure integer programming problems in which the objective function and constraints remain the same except for changes in the right‐hand side of the constraints. It is possible to solve such families of problems simultaneously to give a global optimum for each problem in the family, with additional problems solved in under 2 CPU seconds. This represents a small fraction of the time necessary to solve each problem individually.

AbstractThis paper presents an application of a method for finding the global solution to a problem in integers with a separable objective function of a very general form. This report shows that there is a relationship between an integer problem with a separable nonlinear objective function and many constraints and a series of nonlinear problems with only a single constraint, each of which can be solved sequentially using dynamic programming. The first solution to any of the individual smaller problems that satisfies the original constraints in addition, will be the optimal solution to the multiply‐constrained problem.

The effect of the type of infant day care and the stringency of legislation regarding infant day care was studied in supervised family day care and centre group care in Toronto, Ontario and Winnipeg, Manitoba. The ABC Checklist (Honig and Lally, 1973) was used to measure infant-caregiver interaction (N=73) and an Environmental Checklist was developed to evaluate the physical set-up of the care arrangements (N=45). Questionnaires were received from 47 caregivers and 65 care receivers indicating satisfaction with and preference for their infant day care arrangements. The eight clusters of behaviors in the ABC Checklist were analyzed and showed significant (p<.05) differences within stringency of legislation and type of care arrangement in 12 of 24 t-tests. Analyzing the 40 individual categories of the ABC Checklist 34 of the 160 t-tests showed significant (p<.01) differences in caregiver infant behavior within stringency of legislation and type of care arrangement. In both above sets of analyses the direction of the differences was inconsistent. The chi-square statistic was used to analyze differences between the four experimental groups in the 11 categories of the Environmental Checklist. Twelve of the 44 chi-square tests showed significant (p<.05) differences between stringency of legislation and type of care arrangement but the direction of the differences was inconsistent. The apparently ambivalent reactions of the care-givers and care receivers regarding satisfaction with the preference for the infant care arrangement made statistical analysis inappropriate. The study did not provide support for the proposition that where more stringent legislation is present a higher quality of care is likely to be available.

Advocates for transparent and corruption-free government agree that independent Inspectors General are a critical asset in ensuring that public funds are not wasted or endangered by corrupt officials. More and more states and cities in the U.S. now have Inspectors General as part of their oversight structures, and the numbers keep going up. But setting up an Inspector General's office and providing it with some form of independent powers and a budget does not always guarantee a happy ending for seekers of honest and efficient government, even when an OIG is demonstrably successful at its mission of saving taxpayer money by revealing fraud and waste. Both Louisiana State Inspector General Stephen Street and former New Jersey State Inspector General Mary Jane Cooper have faced numerous challenges to their offices over the last few years. These challenges came in different forms and from different places, but all threatened the very existence of these critical oversight entities.

AbstractA theoretical and computational investigation is made of the performance of a dynamic‐programming‐based algorithm for nonlinear integer problems with various types of constraints. We include linear constraints, aggregated linear constraints, separable nonlinear constraints and constraints involving maxima and minima. Separability of the objective function is assumed. The new feature of the algorithm is that two types of fathoming or pruning are used to reduce the size of tables and number of computations: fathoming by bounds and fathoming by infeasibility.

AbstractA mean‐variance portfolio selection model with limited diversification is formulated in which transaction and management costs are incorporated as the sum of a linear cost and a fixed cost. The problem is a fixed charge integer programming problem solved by hypersurface search using dynamic programming. Fathoming is performed in the forward pass of dynamic programming so that values of the state variable which correspond to infeasible solutions are eliminated from the tables. This logic permits the solution of problems with 20–30 possible investments.

AbstractAn exact method for solving all‐integer linear‐programming problems is presented. Dynamic‐programming methodology is used to search efficiently candidate hyperplanes for the optimal feasible integer solution. The explosive storage requirements for high‐dimensional dynamic programming are avoided by the development of an analytic representation of the optimal allocation at each stage. Computational results for problems of small to moderate size are also presented.

Israel is using starvation as a weapon of war and the international community must exercise its 'responsibility to protect'.

This study explores HIV risk in a small group of Black African women school teachers in South Africa. We used a two-part questionnaire with inductive thematic analysis to explore their private and personal sexual attitudes, as well as their perceptions of male attitudes about sexuality. Key themes are: a desire for power over personal choices, submission to male control in sexual relationships, HIV concern, and the high value these women place on sexual relationships. Although they understood the mechanisms for HIV transmission and enjoyed a degree of financial independence, some of their efforts to avoid HIV risk in sexual relationships, as well as their efforts to communicate about sexuality, were compromised by gendered power dynamics. The results from this study also highlight some gendered strategies they use to preserve their health and relationships. We conclude that an intersectional approach best addresses the problem of preventing HIV/AIDS within an inflexible post-colonial patriarchal structure.