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The purpose of this paper is to study tuneable positive temperature coefficient (PTC) effect in polymer-wax-carbon composite resistors. The resistivity dependence on temperature of composite resistors made of carbon fillers dispersed in an organic matrix is known to be strongly affected by the matrix thermal expansion. High PTC effects, i.e. essentially switching from resistive to quasi-insulating behaviour, can be caused by phase changes in the matrix and the assorted volume expansion, a behaviour that has been previously shown with both simple organic waxes and semi-crystalline polymers. However, waxes become very liquid on melting, possibly resulting in carbon sedimentation, and tuneability of semi-crystalline polymers is limited.

The authors therefore study a ternary polymer-wax-conductor (ethylcellulose-octadecanol-graphite) composite resistor system, where polymer and wax fuse to a viscous liquid on heating, and re-solidify and separate by crystallisation of the wax on cooling.

It is shown that with appropriate formulation, the resulting resistors exhibit strong PTC effects, linked with the melting and crystallisation of the wax component. The behaviour somewhat depends on sample history, and notably cooling speed.

The phase equilibria and transformation kinetics of the polymer-wax system (including possible wax polymorphism), as well as the exact mechanism of the conductivity transition, remain to be investigated.

As many compatible polymer-wax systems with different melting/solidification behaviours are available, ternary polymer-wax-conductor composite PTC resistors allow a high tuneability of properties. Moreover, the high viscosity in the liquid state should largely avoid the sedimentation issues present with binary wax-conductor systems.

New Public Management (NPM) was widely welcomed in the early 1990s of the last century in Switzerland. In accordance with different diagnoses of insufficiency against the public bureaucracies, several NPM programs on all three levels of the Swiss state were launched. But interestingly, most of them did not succeed: they were abandoned, voted down by the electorate, and where they were completed, not much has really changed. So the question from a sociological point of view is, how and why did this happen? To find preliminary answers, NPM is described as a particular professional orthodoxy and confronted with the findings of two ethnographic case studies. What clearly becomes visible is how organizational and professional cultures were neglected by the technical approach of the NPM. This gave way to phenomena like free riding on a reform within the organizations, and in one case to a “fordization” of work resulting in a decrease in workplace quality. If public management seeks an impact in the future, it has to account for the culture within organizations more thoroughly and should seek to use context-sensitive language.

The Navy Nurse Corps is part of a team of professionals that provides high quality, economical health care to approximately 700,000 active duty Navy and Marine Corps members, as well as 2.6 million retired and family members. Navy Nurse Corps manpower management efficiency is critical to providing this care. This paper aims to focus on manpower planning in the Navy Nurse Corps.

The Nurse Corps manages personnel primarily through the recruitment process, drawing on multiple hiring sources. Promotion rates at the lowest two ranks are mandated, but not at the higher ranks. Retention rates vary across pay grades. Using these promotion and attrition rates, a Markov model was constructed to model the personnel flow of junior nurse corps officers.

Hiring sources were shown to have a statistically significant effect on promotion and retention rates. However, these effects were not found to be practically significant in the Markov model. Only small improvements in rank imbalances are possible given current recruiting guidelines. Allowing greater flexibility in recruiting practices, fewer recruits would generate a 25 percent reduction in rank imbalances, but result in understaffing. Recruiting different ranks at entry would generate a 65 percent reduction in rank imbalances without understaffing issues.

Policies adjusting promotion and retention rates are more powerful in controlling personnel flows than adjusting hiring sources. These policies are the only means for addressing the fundamental sources of rank imbalances in the Navy Nurse Corps arising from current manpower guidelines.

The paper shows that modeling to improve manpower management may enable the Navy Nurse Corps to more efficiently fulfill its mandate for high‐quality healthcare.

This paper aims to describe two scenarios where the problem of information search interacts with the firm’s investment decisions. Investment decisions cannot be made separately from the need to acquire information.

The scenarios are illustrated with easy-to-follow numerical examples. Vignettes put the numerical examples in their real-world context.

In both scenarios, the firm should choose what might myopically appear as the lower net per value (NPV) alternative to efficiently deal with the information search problem.

Long-term investments are an important topic in the study of both accounting and finance, but it is in the study of accounting where information issues related to long term investments come to the fore. The traditional textbook approach on whether to accept long-term investment opportunities is to use the NPV rule. However, as illustrated in this note, in many important situations where information search is crucial to investment choice, the NPV rule will not lead to efficient investment decisions.

The impact of education and research skills on the strategic digital transformation of education is straightforward. In this context, the Saudi National Institute of Health plays a pivotal role in the design and implementation of a resilient and robust strategy for the development of skills and competencies to young health professionals. In this chapter, the authors provide a brief overview of the Vision 2030 in Saudi Arabia and its basic priorities in the areas related to the Education and Research in the healthcare domain. The authors also elaborate on the key plans and initiatives undertaken by the education and research skills directory of the Saudi National Institute of Health (SNIH) towards transformative learning with impact on the implementation of the Vision 2030.

X = multiple interpretations

This paper gives a bibliographical review of the finite element and boundary element parallel processing techniques from the theoretical and application points of view. Topics include: theory – domain decomposition/partitioning, load balancing, parallel solvers/algorithms, parallel mesh generation, adaptive methods, and visualization/graphics; applications – structural mechanics problems, dynamic problems, material/geometrical non‐linear problems, contact problems, fracture mechanics, field problems, coupled problems, sensitivity and optimization, and other problems; hardware and software environments – hardware environments, programming techniques, and software development and presentations. The bibliography at the end of this paper contains 850 references to papers, conference proceedings and theses/dissertations dealing with presented subjects that were published between 1996 and 2002.

Water‐borne coatings Increasing use of water‐borne emulsion coatings for original equipment manufacturers (OEM) and product finishes is requiring greater efficiency in coalescing‐aid solvents, an Eastman Chemical Co. representative said at a recent Chicago Society for Coatings Technology meeting. Eastman's Ronald K. Litton said emulsions designed for OEM and industrial applications have higher glass transition temperatures than emulsions used in architectural paints. That requires higher levels of coalescing aid to achieve good film formation. As a result, coalescing‐aid efficiency with a given emulsion system is a key factor, both from environmental (lower‐volatile organic compound (VOC)) and economic standpoints. Several properties should be examined when a coalescing aid is selected for water‐borne emulsion industrial coatings. The formulator should consider the evaporation rate and solubility parameter of the coalescing aid, along with its distribution pattern in a specific emulsion system. Those properties are important in defining the efficiency of a coalescing aid in terms of its ability to lower the minimum film‐forming temperature (MFFT) of an emulsion system. The coalescing aids also must be hydrolytically stable to provide minimum loss of efficiency due to ageing, Litton said. He showed several charts designed to assist formulators in the selection of optimum coalescing aids for emulsion systems. At the same conference, James T.K. Woo of The Glidden Co. discussed the grafting of high‐molecular‐weight epoxy resins with styrene‐methacrylic acid monomers, producing a water‐reducible copolymer. Grafting takes place at the aliphatic carbons of the epoxy resin, according to carbon‐13 NMR spectroscopy. The study was a follow‐up to a paper presented 14 years ago. Woo said recent research indicates that five grafting “peaks” were identified on a 400 megacycle carbon‐13 nuclear magnetic resonance spectroscopy instrument. The paper provided several theoretical calculation on grafting. Three of the graft peaks resulted from grafting at the secondary methylene carbons ‐CH2‐ and two resulted from grafting at the tertiary carbon ‐CH‐. The ratio of grafting at ‐CH2‐ to ‐CH‐appears to be 2.7:1 — lower than the 4:1 ratio of protons present on the aliphatic carbons that are susceptible to hydrogen abstraction leading to grafting. That indicates that the tertiary hydrogen is somwhat more susceptible to grafting than the methylene hydrogens, he said.