Public Article / The Constitution of the Republic of South Africa, 1996 (Act 108 of 1996) and conclusive Acts record that effective human-resource management, career-development and training practices must be cultivated to maximise human potential. The unique nature and wide range of activities of the South African National Defence Force assign exceptional demands on the management expertise of military commanders. Therefore, the importance of effective training and for the purpose of this article, effective management training for mid-level commanders is indisputable. Against this background, a new management model is presented and the resulting training needs are empirically investigated in this article. Both qualitative and quantitative methods were used in the survey, targeted 165 mid-level commanders in the South African National Defence Force. The empirical results of the study suggested that the existing management training for mid-level commanders fails to meet expectations primarily because of the non-existence of an appropriate management model. Thus, the article present a contemporary management model as foundation for management training of mid-level commanders in the South African National Defence Force. The management model also sanctions applicable standards for the development of management skills and appropriate competencies of military commanders.

This dissertation is a multidisciplinary study combining both archaeological andpaleoecological data to examine the rise of early Formative societies in Uruguay, La Plata Basin.It is contextualized within broader anthropological concerns related to the emergence of culturalcomplexity, the significance of ritual and public architecture in intermediate-level societies, andthe role of human-environment interactions during the mid-Holocene. This investigationgenerated the first Late Quaternary paleoclimatic record, based on pollen and phytolith analyses,documenting that the mid-Holocene (ca. 6,620 to ca. 4,040 bp) was a period of environmentalflux and increased aridity. It describes the occupational history of the Los Ajos site from thecreation of a household-based community integrating a centralized communal space during thePreceramic Mound Component (ca. 4,120 – 3,000- 2,500 bp) to the Ceramic Mound Component(ca. 3,000 2,500 bp to the Contact Period), where Los Ajos acquired a strong public ritualcharacter through the formatilization and spatial segregation of its mounded architecture. Duringthe Ceramic Mound Period, the site exhibited both internal stratification (inner versus outerprecincts) and dual asymmetrical architecture in its central sector, which suggest the emergenceof incipient social differentiation. This study also marks the earliest occurrence of at least twodomesticated crops in the region: corn (Zea mays) and squash (Cucurbita spp.), showing that theearly Formative societies adopted a mixed economy shortly after 4,120 bp. Collectively, theseresults challenge the long-standing view that the La Plata Basin was a marginal area byevidencing an early and idiosyncratic emergence of social complexity never before registered inthis region of South America.

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This essay examines whether an investment in tertiary education in mid-age increase the probability to remain in the labor market after age 65 in Sweden. In addition, we analyze whether there is any difference in the probability to continue work after 65 if individuals choose to invest in tertiary education in mid-age or in any other age. This study utilizes already existing data that is a combination of a questionnaire survey and Swedish register data. In the sample there are 5235 individuals who are retired and 881 who are still in the labor market, born between 1938 and 1949. The implemented method is a linear probability model to obtain mean marginal effect. The results indicate that individuals who invested in tertiary education in mid-age have a higher probability to remain in the labor market after 65 than individuals with no tertiary education. There is, however, no statistically significant difference in probability depending on when they decide to invest in tertiary education.

This thesis is concerned with the prediction of the vibro-acoustic response of structures with uncertain properties in the mid frequency region. The motivation for this research is the growing need of engineers to understand the responses of a group of similar structures ranging from vehicles, aircraft and aerospace structures, to household whitegood appliances. These structures are complex in geometry and may possess variability in their material or geometric properties, as well as variation arising from the assembly and manufacturing processes. Small variations can have a significant effect on a dynamic response of a structure, and the effect of structural uncertainties increases as the frequency increases. Deterministic modelling techniques such as finite element analysis are only suitable to model complex structures at low frequencies. Furthermore, FEA cannot easily account for uncertainty or randomness in structural parameters. High frequency dynamic predictive techniques such as Statistical Energy Analysis can account for structural uncertainty but is limited to structures with high modal density. There exists a frequency range between the two methods in which neither technique can be applied with great confidence. The objective of this thesis is to investigate predictive techniques for mid frequency vibration analysis of dynamic systems with structural uncertainties. The first part of this work is to numerically characterise the effect of a range of uncertainties on the modal statistics of structures. The degree of uncertainty required to achieve universality of the statistical properties is investigated. This is achieved by examining the modal statistics of dynamic systems with a range of uncertainty, corresponding to uncertainty due to mass and stiffness perturbations, uncertainty at the boundaries of a structure, uncertainty in the coupling between structures, uncertainty in the material properties of a structure and uncertainty in the geometry of a structure. Several structures are examined corresponding to a plate with masses and/or linear springs added at random locations, a plate with torsional springs attached at random locations along its boundary edges, two plates coupled by linear springs at random locations, a mass-loaded coupled L-shaped plate, a mass-loaded frame-plate structure, and a plate with varying Young's modulus, density and thickness. The natural frequencies of the aforementioned structures have been derived using either the Lagrange-Rayleigh-Ritz technique, finite element analysis, or the use of interval analysis in conjunction with FEA. The natural frequency statistics of structures with uncertain properties are observed using two statistical measures; the statistical overlap factor and the probability density function of the spacing between successive natural frequencies. The statistical overlap factor is defined by the variation in a natural frequency from its mean value measured across an ensemble of nominally identical structures with uncertainty. For a single ensemble member, the probability density function of the spacing between successive natural frequencies is compared to a Rayleigh distribution of the mean frequency spacing. A Rayleigh distribution of modal spacings is a feature of the universality exhibited by structures with uncertainty. To further investigate the effect of structural uncertainty on the vibrational characteristics of structures, the interval analysis is applied to finite element models of a plate with uncertainty in its material properties and dimensions. Using this method, the Young's modulus, density and thickness of a rectangular plate were set to vary by a small amount within predefined bounds. Using finite element equations, the natural frequencies and modeshapes of the structure were then determined in terms of the Young's modulus, density and plate thickness. For the mass and spring loaded plates, the springs were shown to affect the lower order modes while the masses had a significant effect on the higher order modes. As the frequency increased, only a small amount of perturbation was sufficient to affect the natural frequencies of a structure. Using the interval analysis method, the variation of the natural frequencies from their deterministic value increased as the frequency increased. An ergodic hypothesis was used to examine the responses statistics of structures with uncertainty. Three structures have been computationally studied corresponding to two plates coupled by springs, an L-shaped plate and a frame plate structure. Uncertainty has been generated for the two coupled plates by locating the springs randomly across the surface of the two plates. For the L-shaped plate and a frame plate structure, uncertainty was generated by randomly positioning small masses across the plates. Using the ergodic hypothesis, the frequency averaged response on one member of an ensemble is compare with the ensemble averaged response. It was found that the ensemble averaged response was well predicted by a frequency averaged response of a single ensemble member. The width of the frequency averaging band was shown to have a large influence on the quality of the match between the frequency and ensemble averaged responses. Results were significantly improved using a frequency averaging bandwidth which varies proportionally to frequency. Finally, experiments have been conducted on an L-shaped plate, a frame plate structure and a vehicle to validate the computational results for the natural frequency and response statistics.

Silicon has been the material of choice of the photonics industry over the last decade due to its easy integration with silicon electronics as well as its optical transparency in the near-infrared telecom wavelengths. Besides these, it has very high refractive index, and also a broad optical transparency window over the entire mid-IR till about 8[Mu]m. Photonic crystal is well known that it can slow down the speed of light. It also can provide a universal platform for microcavity optical resonators with high quality factor Q and small modal volumes. The slow light effect, high Q and small modal volumes enhance light-matter interaction, together with high refractive index of silicon can be utilized to build a highly sensitive, high throughput sensor with small footprint. In this research, we have demonstrated highly compact and sensitive silicon based photonic crystal biosensor by engineering the photonic crystal microcavity in both cavity size and cavity-waveguide coupling condition. We have developed solutions to increase biosensor throughput by integrating multimode interference device and improving the coupling efficiency to a slow light photonic crystal waveguides. We have also performed detailed investigations on silicon based photonic devices at mid-infrared region to develop an ideal platform for highly sensitive optical absorption spectroscopy on chip. The studies have led to the demonstration of the first slot waveguide, the first photonic crystal waveguide, and the first holey photonic crystal waveguide and first slotted photonic crystal waveguide in silicon-on-sapphire at mid-infrared. The solutions and devices we developed in our research could be very useful for people to realize an integrated photonic circuit for biological and chemical sensing in the future. / text

Cereal grains share many common traits, but they also have different internal structures, nutrient values, degradation kinetics and digestion features. Heat treatments are commonly used in the feed industry. It is known that heat is able to change the nutrient values of the feed but the effect could be equivocal. In order to understand the effects of heat processing on internal structure and nutrient availability of cereal grains, two batches of wheat, triticale and corn were divided into three groups (control/raw (unheated), dry heating and moist heating) and processed at 121 °C for 80 min. Basic chemical analysis and in situ, in vitro assays were conducted and CNCPS, DVE/OEB and NRC-2001 models were used to determine the nutrient availability of the grains. In addition, two mid-IR molecular spectroscopy techniques (Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) and Synchrotron Radiation Infrared Microspectroscopy (SR-IMS)) were used to gain an insight into the heat-induced changes in the functional groups. Significant (P<0.05) differences were found between the cereal grains in their nutritional availabilities, including their chemical characteristics, protein and carbohydrate fractions, energy values, the ruminal degradation kinetics, hourly effective rumen degradation ratios, potential N-to-energy synchronization, and intestinal digestion of cereal grains. Compared to dry heating, moist heating had more impact on altering the nutrient profiles and showed the potential to increase the nutrient availability of wheat and triticale for dairy cattle. Significant differences (P<0.01) were detected between different feeds and heat treatment groups by using the ATR-FTIR technique. Results were found in consistency with the conventional chemical and animal studies mentioned above despite when using the SR-IMS technique. Significant (P<0.05) correlations were detected between some structure spectral characteristics and nutrient digestion traits. In conclusion, the moist heating had more profound impact than the dry heating in increasing nutrient supplies to ruminants in wheat and triticale. The heat-induced effects found in corn were less positive. The ATR-FTIR technique could detect the internal structural changes in cereal grains, while the sensitivity and accuracy of the SR-IMS technique were not proved in this study.

The mid-infrared wavelength region (2-20 µm) is of great utility for a number of applications, including chemical bond spectroscopy, trace gas sensing, and medical diagnostics. Despite this wealth of applications, the on-chip mid-IR photonics platform needed to access them is relatively undeveloped. Silicon is an attractive material of choice for the mid-IR, as it exhibits low loss through much of the mid-IR. Using silicon allows us to take advantage of well-developed fabrication techniques and CMOS compatibility, making the realization of on-chip integrated mid-IR devices more realistic. The mid-IR wavelengths also afford the opportunity to exploit Si's high third-order optical nonlinearity for nonlinear frequency generation applications. In this work, we present a Si-based platform for mid-IR photonics, with a special focus on micro-resonators for strong on-chip light confinement in the 4-5 μm range. Additionally, we develop experimental optical characterization techniques to overcome the inherent difficulties of working in this wavelength regime. First, we demonstrate the design, fabrication, and characterization of photonic crystal cavities in a silicon membrane platform, operational at 4.4 μm (Chapter 2). By transferring the technique known as resonant scattering to the mid-IR, we measure quality (Q) factors of up to 13,600 in these photonic crystal cavities. We also develop a technique known as scanning resonant scattering microscopy to image our cavity modes and optimize alignment to our devices. Next, we demonstrate the electro-optic tuning of these mid-IR Si photonic crystal cavities using gated graphene (Chapter 3). We demonstrate a tuning of about 4 nm, and demonstrate the principle of on-chip mid-IR modulation using these devices. We then investigate the phenomenon of optical bistability seen in our photonic crystal cavities (Chapter 4). We discover that our bistability is thermal in origin and use post-processing techniques to mitigate bistability and increase Q-factors. We then demonstrate the design, fabrication, and characterization grating-coupled ring resonators in a silicon-on-sapphire (SOS) platform at 4.4 μm, achieving intrinsic Q-factors as high as 278,000 in these devices (Chapter 5). Finally, we provide a quantitative analysis of the potential of our SOS devices for nonlinear frequency generation and describe ongoing experiments in this regard (Chapter 6). / Engineering and Applied Sciences

The fiction of Dickens and Collins abounds with references to the illegitimate. In the mid-Victorian period there is an increase in illegitimate characters and circumstances which relates both to the topicality of the issue and to events in the authors individual and collaborative private lives. Illegitimacy addresses personal and social anxieties in four major novels of the 1850s and 1860s: Bleak House (1852-53), Little Dorrit (1855-57) by Dickens and The Woman in White (1860) and No Name (1862) by Collins. Dickens analyses illegitimacy in Bleak House psychologically and socially through Esther Summerson, but her narrative reveals contradictions between Dickens challenge of contemporary attitudes towards the illegitimate and his subscription to the moral code behind the views. In Little Dorrit Dickens confines his study of illegitimacy to character in order to examine the psychological consequences of illegitimacy on the individual. The novel suggests that illegitimacy is another form of social and legal imprisonment. In contrast in The Woman in White Collins exploits the sensationalism surrounding illegitimacy by using it to create an exciting plot at the inception of the sensation genre. His suggestion in this novel that bastards are legally blank and able to reconstruct their identity is continued in No Name; this later novel directly challenges the laws defining and controlling illegitimacy. While Collins never matches Dickens integration of social and moral issues into the novel s structure, the older author appreciated Collins strength in creating detective narratives. Illegitimacy was relevant to the private lives of both Dickens and Collins in the period. While the authors always tried to keep their public and private lives separate, their romantic relationships reveal a personal motive for discussing the plight of the illegitimate in their novels. There is a distinct possibility that Dickens had an illegitimate child with his mistress Ellen Ternan while Collins had three illegitimate children with Martha Rudd. The novels articulate the tension between what Dickens and Collins the authors were trying to achieve and what the novels themselves disclose.

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