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Agility is a major concern for enterprises across manufacturing and service sectors. This paper supports the claim that process-oriented approaches are useful for agility improvement projects. It builds on an existing process-oriented framework for agility improvement projects to identify agility enabling principles and tools in manufacturing. Collectively, the framework processes, enabling principles and tools contribute the operationalization of agility improvement initiatives. Surveyed practitioners' confirm this general finding as well as the relevance of the framework to middle management, in particular in Small-and-Medium Sized enterprises. [ABSTRACT FROM AUTHOR]

Manufacturing firms are embracing new technologies in the fourth industrial revolution. Firms are adopting various digital technologies to become smart and intelligent system. One such technology used widely in manufacturing sector is cyber physical system (CPS). A CPS incorporates a wide range of trans-disciplinary approaches, comprising computer science, cybernetic enhancements theory, design and process science, mechanical engineering and mechatronics, and manufacturing systems. CPS ensures proper connectivity and interaction of physical entities with the online system. Many manufacturing firms are facing challenges in adopting CPS such as low skills to adopt CPS, risk of cyber attach and many more. In this regard, this article presents a review on the concept of CPS along with its adoption challenges. Various challenges arise in adoption of CPS have been discussed in detailed. Further, drivers associated with adoption of CPS technology in manufacturing were also discussed. The drivers such as Legislation and Standardization, Management Strategy and Skilled human resources are observed as significant one for the adoption of CPS in manufacturing systems. The present study will help industrial experts to have clear understanding about the obstacles in adoption of CPS practices in manufacturing sector. [ABSTRACT FROM AUTHOR]

Industry 4.0 is a new paradigm in the technology world. Through this project a set of research problems in the realm of Industry 4.0 are presented to the students. Research problems are selected broadly from the domain of Industry 4.0 which includes current and emerging technologies. Students are also given the opportunity to select the topics, however, they need to receive the instructor's approval. During the project, students conduct literature reviews on the selected topics. The cohort size of the pilot class is 23 students; ten teams with two students each, and one team with three students. The objectives and deliverables of the project are clearly stated in advance to keep students informed. The objective of this project is to incorporate Industry 4.0 skills and knowledge to the students in addition to learn the methods to stay current in industry. The project deliverables are (1) students will present their work to the rest of the class, and (2) submit a reflective paper on their experience. This paper will discuss the setup of research problems, survey results of the student experience before and after working on the project, and summary of findings on the student experience from the reflective papers. Reflective papers serve as a tool both to summarize the student experience and for continuous improvement in the context of this project and future studies. [ABSTRACT FROM AUTHOR]

In spring 2022, members of the Engineering Technology (ET) Industrial Advisory Board (IAB) discussed the importance of Industry 4.0 awareness in the region, and the department has been enduring its work in incorporating the various facets of this evolving technology in the ET curriculum. Integration of emerging technologies, such as Industry 4.0, technological skills to meet the demand of the regional workforce can be accomplished by few methods. One such method is integration of professional publications in the coursework. This paper will elucidate the results of successful implementation of Industry 4.0 concepts in ET curriculum through a pilot summer course, Control Systems. Additionally, the authors aim to present the opportunities for expansion to include other professional journals for continued implementation in the various concentrations of ET. This paper aims to discuss and present the key findings in the following areas: (1) Explicate integration of student knowledge gained from reading publications from professional journals such as the International Society of Automation (ISA) - InTech Journal, in implementing Industry 4.0 in the ET curriculum. (2) Present the results along with a reflective analysis of the implementation in the pilot Summer III 2022, Control Systems course. (3) Present the process for integration of additional professional journals such as IEEE, Journal of Engineering Technology (ASEE), and Journal of Manufacturing Processes (SME), in the concentration-specific courses in the ET Program. (4) Deliberate the importance of integration of professional journals as a teaching strategy to augment the classroom learning experience in the department's ETAC (Engineering Technology Accreditation Commission) of ABET accredited ET programs in Austin Peay State University (APSU). The full paper will elucidate the above areas (1-4) in the efficacious integration of professional journals in the ET curriculum, description of assessment methods (class presentation and written report) used to evaluate the pilot project, statement of results, and a conclusion. [ABSTRACT FROM AUTHOR]

Organisations face a new challenge that results from the increasing demand for customised products, motivated by trends that can quickly shift. The inclusion of the consumer in the manufacturing processes (Social Manufacturing) also raises new challenges regarding their representation. Based on three consumer satisfaction categories: (1) Perceived Value; (2) Consumer Expectation; (3) Consumer Loyalty; this work proposes a multidimensional representation of the consumer in three dimensions: (1) Personalisation; (2) Opinion; (3) Engagement. This model is based on the definition of complex networks, and the multidimensional aspect allows organisations to isolate and combine different dimensions to better understand their consumers, their opinions, and their demands for new products. The multidimensional characteristic of the model, namely the isolation and combination of dimensions, can help organisations understand if common customisation demands share common background, understand what demands should be addressed or prioritised, or even anticipate trends. [ABSTRACT FROM AUTHOR]

This paperwork is dedicated to the research of the quality of height anomalies derived from the Global Geopotential Models GOCO over the Serbia territory. Three different types of approaches for the same model were considered: time wise, space wise and direct approach. The quality of the mentioned models is determined by comparison with terrestrial data of height anomalies, that are relate to the second high precision leveling network of the Republic of Serbia (the period of realization of tide gauges observations for determining the vertical position of the reference surface of the height reference system of the Republic of Serbia is 1971.0 years) and European Terrestrial Reference System 1989, realization ETRF2000, epoch 2010.63. By direct comparison, it was established that all models give almost identical data on the territory of Serbia and that with the application of the model one can approximate height anomalies at the territory of Serbia with a mean value of maximum 7 cm and with a standard deviation of 20 cm. Besides of this, models are compared in their spectral domains, with each other and with the model EGM2008, by comparison their degree and error degree variances. [ABSTRACT FROM AUTHOR]

A strong negative magnetoresistance is observed in a high-mobility two-dimensional electron gas in a GaAs/Al0.3Ga0.7As quantum well. We discuss that the negative magnetoresistance consists of a small peak induced by a combination of two types of disorder and a huge magnetoresistance explained by the interaction correction to the conductivity for mixed disorder. [ABSTRACT FROM AUTHOR]

We report on a photoconductive gain in semiconductor quantum wires which are lithographically defined in an AlGaAs/GaAs quantum well via a shallow-etch technique. The effect allows resolving the one-dimensional subbands of the quantum wires as maxima in the photoresponse across the quantum wires. We interpret the results by optically induced holes in the valence band of the quantum well which shift the one-dimensional subbands of the quantum wire. Here we demonstrate that the effect persists up to a temperature of about 17 Kelvin. [ABSTRACT FROM AUTHOR]

Within this paper the evaluation and comparison test of a series of global geopotential models (GGM) is shown using available terrestrial data from the territory of Serbia. Using the model of European Improved Gravity 6C2 (EIGEN-6C2), then the model of Gravity Observation Combination 02S 03S (GOCO02S and GOCO03S) as well as the model of the Earth Gravitational Model 2008 (EGM08) the anomalies of free air in 98776 points of gravimetric survey of Serbia were determined as well as the height anomalies in 1073 points wherein the discreet values of height anomalies were known. The discreet values of height anomalies were calculated as differences between orthometric heights, determined by high precision levelling and the ellipsoidal heights determined by global system for positioning (GPS/dh), and in the points of gravimetric survey of Serbia the free air anomalies related to the Geodetic Reference System 1980 (GRS80) and to the International Gravity Standardization Net 1971 (IGSN71) were determined. Along with all mentioned above the results gained by using said models were separately compared with the data obtained by using the Earth Gravitational Model 1996 (EGM96). [ABSTRACT FROM AUTHOR]

The anisotropic splitting of intersubband spin plasmons, resulting from spin-orbit coupling, is studied by angle-resolved inelastic light scattering on a [001]-oriented GaAs/AlGaAs quantum well. Confirming theoretical predictions made in [C. A. Ullrich and M. A. Flatté, Phys. Rev. B 68, 235310 (2003)], this splitting is proven to exhibit a characteristic two-fold symmetry with the in-plane orientation, and to increase with increasing modulus of the excitation momentum. This opens the way to a more complete investigation, aiming at evidencing the existence of a collective spin-orbit field driving these excitations. [ABSTRACT FROM AUTHOR]

Successful industrial goods-delivering companies are always looking for ways to develop and grow their business. A strong present trend is to expand the traditionally tangible offering by integrating intangible offerings i.e. services. In academia the term industrial product-service systems (IPS2) are being used to describe this paradigm shift. However, a systematic review of the IPS2 literature is lacking. In this paper publications regarding IPS2 are systematically reviewed. The result of our review has been categorized under five themes that we found characterizes IPS2: delivery, processes, value creation networks, knowledge management, and business models. Based on our findings a discussion is made and future research directions are identified. [ABSTRACT FROM PUBLISHER]

The competition between the Kondo effect and the Ruderman-Kittel-Kasuya-Yoshida (RKKY) interaction is investigated in a double quantum dots system, coupled via a central open conducting region. A perpendicular magnetic field induces the formation of Landau Levels which in turn give rise to the so-called Kondo chessboard pattern in the transport through the quantum dots. The two quantum dots become therefore chirally coupled via the edge channels formed in the open conducting area. In regions where both quantum dots exhibit Kondo transport the presence of the RKKY exchange interaction is probed by an analysis of the temperature dependence. The thus obtained Kondo temperature of one dot shows an abrupt increase at the onset of Kondo transport in the other, independent of the magnetic field polarity, i.e. edge state chirality in the central region. [ABSTRACT FROM AUTHOR]

Spins in semiconductor structures may allow for the realization of scalable quantum bit arrays, an essential component for quantum computation schemes. Specifically, hole spins may be more suited for this purpose than electron spins, due to their strongly reduced interaction with lattice nuclei, which limits spin coherence for electrons in quantum dots. Here, we present resonant spin amplification (RSA) measurements, performed on a p-modulation doped GaAs-based quantum well at temperatures below 500 mK. The RSA traces have a peculiar, butterfly-like shape, which stems from the initialization of a resident hole spin polarization by optical orientation. The combined dynamics of the optically oriented electron and hole spins are well-described by a rate equation model, and by comparison of experiment and model, hole spin dephasing times of more than 70 ns are extracted from the measured data. [ABSTRACT FROM AUTHOR]

High-mobility two-dimensional electron systems may be one of the bases of future spintronic devices, where the spin states of ballistic electrons could be manipulated via external gate voltages and the resulting spin-orbit fields. Therefore, the knowledge of spin dynamics in such systems is of technical interest and offers on the other side an exciting view on the underlying physics. Here, we present time-resolved Faraday rotation measurements in a high-mobility two-dimensional electron system in a GaAs/AlGaAs quantum well structure grown along the [001] direction. Even without applied external magnetic fields the optically generated spin ensemble shows a coherent precession about the effective spin-orbit field. If a nonquantizing magnetic field is applied normal to the sample plane, the effective spin-orbit fields are rotated by the cyclotron motion of the electrons. This rotation leads to fast oscillations in the spin polarization about a nonzero value and an strong increase of the spin dephasing times. The measurement data is in excellent agreement with a model based on a kinetic equation approach. [ABSTRACT FROM AUTHOR]

With the recent discovery of very long hole spin decoherence times in GaAs/AlGaAs heterostructures of more than 70 ns in two-dimensional hole systems, using the hole spin as a viable alternative to electron spins in spintronic applications seems possible. Furthermore, as the hyperfine interaction with the nuclear spins is likely to be the limiting factor for electron spin lifetimes in zero dimensions, holes with their suppressed Fermi contact hyperfine interaction due to their p-like nature should be able to show even longer lifetimes than electrons. For spintronic applications, electric-field control of hole spin dynamics is desirable. Here, we report on time-resolved Kerr rotation and resonant spin amplification measurements on a two-dimensional hole system in a p-doped GaAs/AlGaAs heterostructure. Via a semitransparent gate, we tune the charge density within the sample. We are able to observe a change in the hole g factor, as well as in the hole spin dephasing time at high magnetic fields. [ABSTRACT FROM AUTHOR]

GaMnAs is a highly interesting material system for future spintronic devices. We present a study of nonmagnetic GaAs quantum wells (QW) embedded in AlGaAs barriers, close to a ferromagnetic GaMnAs layer. The samples were grown on semi-insulating GaAs(001) and contain two QWs, where one QW is close to the GaMnAs layer and the other one is farther away (120 nm), and serves as a reference. We studied the influence of the barrier material, e.g. a short-period AlAs/GaAs superlattice. The photoluminescence (PL) of the upper QWs, close to the GaMnAs layer, show a significant broadening. Additionally, time-resolved Faraday rotation (TRFR) reveals that the spin lifetime in the upper QW is up to 30 times longer than that in the lower QW. We attribute these observations to backdiffusion of Mn into the QW during and after growth. Both, the PL and the TRFR, are highly sensitive to small quantities (below 0.05 %) of Mn and allow us to study the efficiency of barrier layers in suppressing Mn diffusion. [ABSTRACT FROM AUTHOR]

The spin dynamics in [001]-grown two-dimensional electron systems (2DES) at low temperatures are governed by the effective spin-orbit fields, which lead to dephasing via the D’yakonov-Perel mechanism. If both the Rashba and the Dresselhaus spin-orbit fields are present and of the same order, their interference causes a large anisotropy of the spin dephasing times for spin orientation along different in-plane directions. This may be observed in time-resolved Faraday rotation measurements using in-plane magnetic fields. The dephasing anisotropy is strongly reduced for increasing carrier density by the increasing importance of the kubic Dresselhaus term. [ABSTRACT FROM AUTHOR]

We present a study of nonmagnetic GaAs quantum wells (QWs) embedded in AlGaAs barriers close to a Ga(Mn)As layer. The photoluminescence (PL) spectra of QWs close (3 – 10 nm) to the Ga(Mn)As layer show a pronounced broadening and quenching of the PL. This may be due to diffusion of Mn ions into the QW during growth. Employing time-resolved Faraday rotation measurements, we observe that the spin lifetime in the QW, separated by 10 nm from the Ga(Mn)As layer, is increased by a factor of 3, as compared to a control well, at a distance of 122 nm. However, in the measured g factors we see no influence of the Mn. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]