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Through the study of leadership, the concept of leadership effectiveness and its importance has emerged. Effective leadership contributes to successful organizations (Amagoh, 2009; Leithwood, Jantzi, & Steinbach, 1999). According to Gordon & Yukl (2004), because of constantly changing environments, it is important to continue research in the leadership and leadership effectiveness fields, especially when it comes to leadership in academia. Using Seiler and Pfister’s (2009) Dynamic Five-Factor Model of Leadership as the theoretical frame, a qualitative study of leadership effectiveness influencers of Agricultural and Extension Education department heads was completed. The research looked at both internal and external influential factors.

Only continuously monitoring cavity pressure allows the detailed recording of the injection molding process in the injection, compression and holding pressure phases. It alone correlates with all significant molding features such as weight, morphology, degree of forming, burr formation, shrink marks and cavities as well as shrinkage and deformation. The cavity pressure not only optimizes the timing of the switching point from the compression to the holding pressure phase, but also serves directly as a criterion for the switching. Molding weights and countless other quality characteristics thereby vary considerably less than with switching based on hydraulic pressure, screw travel or time. Quartz sensors have proved particularly successful for direct and indirect measurement of pressure. Advocates the use of cavity pressure sensors for monitoring and control of the injection molding process and describes commercial products that are available.

The purpose of this work is to investigate the performance of non‐contaminating metal cutting environments and investigate the associated tool chip interface conditions. The work benchmarks flood coolant characteristics and considers gaseous cutting environments as possible alternatives.

Cutting trials were undertaken for a range of cutting environments. Flood coolant was investigated as was dry cutting, compressed air, room temperature nitrogen and liquid nitrogen environments. A range of cutting variables was measured in order to document the effect of cutting environment.

The gaseous component of the liquid nitrogen environment limited the adhesion on the tool face to a region along the flank edge of the tool, shifting rake face conditions from seizure to that of sliding. Tighter chip curl, shorter contact lengths, reduced adhesion and lower feed forces are evidence that liquid nitrogen is acting as a “liquid inert barrier” beneath the chip within the tool/chip interface.

Only one tool work combination has been investigated. More tool work combinations will need to be investigated.

The work demonstrated that it is possible to use environmentally safe environments during metal cutting operations. This reduces the exposure of the environment and machine tool operatives to compounds which have been shown to have detrimental effects on the environment and human health.

The work has led to presenting a hypothesis that liquid nitrogen acts as a “liquid inert barrier” beneath the chip within the tool/chip interface.

This paper aims to provide a more comprehensive understanding of the concept of community archives, offering a critique of the community archives discourse through a historical case study focused on the origins of the Gerber/Hart LGBTQ library and archives in Chicago.

This study explores the archival collections of the founders of the Gerber/Hart library and archives and the librarians that have worked there as a means for understanding the origins of the archival impulse, the rationale for building the collections and the practices that shaped the collections during the first decade of the organization’s history.

The historical analysis of the Gerber/Hart library and archives situates community archives and LGBTQ collections within the broader historical context that lead to the founding of the organization and reveals deep connections to the information professions not previously considered by those studying community archives.

The paper offers a reconceptualization of community archives as archival projects initiated, controlled and maintained by the members of a self-defined community. The authors emphasize the role of the archival impulse or the historical origins of the collection and the necessity for full-community control, setting clear boundaries between community archives and other participatory archival models that engage the community.

The purpose of this study was to introduce three-dimensional printing (3DP) of functionally graded sandwich foams (FGSFs). This work was continued by predicting the mechanical buckling and free vibration behavior of 3DP FGSFs using experimental and numerical analyses.

Initially, hollow glass microballoon-reinforced high-density polyethylene-based polymer composite foams were developed, and these materials were extruded into their respective filaments. These filaments are used as feedstock materials in fused filament fabrication based 3DP for the development of FGSFs. Scanning electron microscopy analysis was performed on the freeze-dried samples to observe filler sustainability. Furthermore, the density, critical buckling load (P_cr), natural frequency (f_n) and damping factor of FGSFs were evaluated. The critical buckling load (P_cr) of the FGSFs was estimated using the double-tangent method and modified Budiansky criteria.

The density of FGSFs decreased with increasing filler percentage. The mechanical buckling load increased with the filler percentage. The natural frequency corresponding to the first mode of the FGSFs exhibited a decreasing trend with an increasing load in the pre-buckling regime and an increase in post-buckled zone, whereas the damping factor exhibited the opposite trend.

The current research work is valuable for the area of 3D printing by developing the functionally graded foam based sandwich beams. Furthermore, it intended to present the buckling behavior of 3D printed FGSFs, variation of frequency and damping factor corresponding to first three modes with increase in load.

The purpose of this paper is to study and compare the mechanical properties and machinability characteristics of additive manufactured titanium alloy Ti-6Al-4V with conventionally produced wrought titanium alloy,Ti-6Al-4V. The difference in mechanical properties such as yield strength, ultimate tensile strength, micro hardness, percentage of elongation and their effect on machinability characteristics like cutting forces and surface roughness are studied. It was found that higher strength and hardness of SLM Ti-6Al-4V compared to wrought Ti-6Al-4V owing to its peculiar acicular microstructure significantly affected the cutting forces and surface roughness. High cutting forces and low surface roughness were observed during machining of additive manufactured components compared to its wrought counterpart because of their difference in strength, hardness and ductility.

Mechanical properties like yield strength, ultimate tensile strength, hardness and percentage of elongation and machinability characteristics like cutting forces and surface roughness were studied for both wrought and additive manufactured Ti-6Al-4V.

Mechanical properties like yield strength, ultimate tensile strength and hardness were higher for additive manufactured components as compared to the wrought component. However additive manufactured components significantly lacked in ductility as compared to the wrought parts. Concerning machining, higher cutting forces and lower surface roughness were observed in additive manufactured Ti-6Al-4V compared to the wrought part as a result of differences in mechanical properties of these differently processed materials.

This paper, for the first time, discusses the machining capabilities of additive manufactured Ti-6Al-4V.

The central focus of this paper is an analysis of the weaknesses of the current structural options that aim to allow older employees to continue working. The point of departure of the analysis is a reappraisal of the questions arising from the employment of older people in the internal and external labour market in Germany. In the course of the investigation it shall become clear that competencies, or rather, the lifelong development of competencies, constitute the key problem in laying the foundations for the further employment of older workers. There is however insufficient data in this field of research, since other than formal qualifications scarcely any information about employees’ skills is available. Particularly in the case of those over the age of 45, one simply “fumbles about in the dark”. When comparing the various structural options (e.g. part‐time work for older people, teamwork, HR planning for the future, etc.) competency development assumes a decisive role. Yet management of competency development in the technocratic sense proves unsuited to meet the requirements for the further employment of older employees. The organisation of competency development should rather be conceptualised as originating from the particular self‐regulating processes and mechanisms in question and should simultaneously be integrated into the company’s human resource and organisational development.

The internal combustion engine operated on gaseous fuels shows great potential in terms of integration of the renewable and traditional sources for an effective solution for clean energy production challenge. Different fuel mixtures that can be used to power the engine are characterized by various combustion properties, which can affect its overall efficiency. The purpose of this paper is to provide reasonable answer, how the operation condition can change due to different fuel, without enormous cost of prototyping processes using physical models a digital model can be seen as promising technique.

Presented work discusses the application, and extensive description of two commercial codes Ansys Fluent and Forte for modeling stationary engine fueled by compressed natural gas (CNG) and biogas. To check the model accuracy, all carried out numerical results were compared against experimental data collected at in-house test rig of single cylinder four stroke engine. The impacts of tested gaseous fuel on the engine working conditions and emission levels were investigated.

Carried out simulations showed good agreement with experimental data for investigated cases. Application on numerical models give possibility to visualize flame front propagation and pollutant formation for tested fuels. The biogas fuel has shown the impaired early flame phase, which led to longer combustion, lower efficiency, power output, repeatability and in some cases higher HC and carbon monoxide (CO) emissions as a result of combustion during the exhaust stroke. Looking at the CO formation it was observed that it instantly accrue with flame front propagation as a result of methane oxidation, while for NOx formation revers effect was seen.

The application of new approach for modeling combustion process in stationary engines fueled by CNG and alternative biogas fuel has been discussed. The cons and pros of the Forte code in terms of its application for engine prototaping process has been discussed.