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An intelligent gas sensor has been developed using thick‐film techniques to create a semiconducting oxide surface with carefully varied catalytic properties. An integral heater causes the surface to react with combustible gases and the resulting resistance map of the surface forms a signature that can be related to the functional groups present in the gas. For example, alcohols, ketones and alkanes have distinct, recognisable signatures on one sensor model.

The purpose of this paper is to based upon the joining and characterization (mechanical and metallurgical) of ferritic stainless steel (SS)-430 using a microwave hybrid heating (MHH) phenomenon.

The preliminary experiments were conducted using nickel-based powder as interface material using a domestic microwave oven at a frequency of 2.45 GHz and 900 W power for 720 s. The processed joint was metallurgically characterized by means of X-ray diffraction, Energy-dispersive X-ray spectroscopy and Field emission scanning electron microscopy. Mechanical characterization was done by means of tensile and Vickers’ microhardness testing to check the hardness and strength of the joint.

The metallurgical study revealed that the microstructure and formation of numerous phases of Fe₂Si₃ accompanied by chromium and nickel carbides. The average hardness of 359 Hv at the center of the joint and 637 Hv around the boundaries of the joint was observed. The tensile strength of the joint was observed to 471 MPa with an elongation of 9.02%. The worn surface of the joint signifies the presence of plastic deformation and it was limited due to the presence of harder phases such as Ni₃Si and Ni₃C.

The concept of microwave joining of metals is a very challenging task as the temperature can not be controlled in the inert atmosphere of the microwave. It has been also observed that at certain elevated temperatures, the material starts absorbing the microwaves; which is unknown. So, a more intensive study is required to overcome these kinds of limitations.

MHH technique can be used to process different materials such as ceramics, composites and polymers. SS-430 joined by microwave heating is highly corrosion resistive and has wide applications in refrigerators cabinet panels, dishwasher linings, chimney liners, lashing wires, etc.

As of the author’s best knowledge, no work has been reported on the joining of SS-430 which has huge potential in the industries. Also, no work has been reported on the characterization of microwave joined SS-430.

This paper aims to present an open‐ended microwave curing system for microelectronics components and a numerical analysis framework for virtual testing and prototyping of the system, enabling design of physical prototypes to be optimized, expediting the development process.

An open‐ended microwave oven system able to enhance the cure process for thermosetting polymer materials utilised in microelectronics applications is presented. The system is designed to be mounted on a precision placement machine enabling curing of individual components on a circuit board. The design of the system allows the heating pattern and heating rate to be carefully controlled optimising cure rate and cure quality. A multi‐physics analysis approach has been adopted to form a numerical model capable of capturing the complex coupling that exists between physical processes. Electromagnetic analysis has been performed using a Yee finite‐difference time‐domain scheme, while an unstructured finite volume method has been utilized to perform thermophysical analysis. The two solvers are coupled using a sampling‐based cross‐mapping algorithm.

The numerical results obtained demonstrate that the numerical model is able to obtain solutions for distribution of temperature, rate of cure, degree of cure and thermally induced stresses within an idealised polymer load heated by the proposed microwave system.

The work is limited by the absence of experimentally derived material property data and comparative experimental results. However, the model demonstrates that the proposed microwave system would seem to be a feasible method of expediting the cure rate of polymer materials.

The findings of this paper will help to provide an understanding of the behaviour of thermosetting polymer materials during microwave cure processing.

This study aims to examine Taiwanese male and female police officers' perceived stress during the COVID-19 pandemic.

Data were analyzed based on surveys conducted with 1,671 officers in various cities and counties between May and July of 2021, during the period of level 3 alert of COVID-19 pandemic in Taiwan.

It was found that officers who perceived poor inter-agency coordination and higher risk of infection, and those who were assigned to home quarantine duty and stationed in the metropolitan areas of Taipei, which suffered the worst spread of infected cases, were more likely to exhibit a higher level of stress. On the other hand, police identity, COVID-19 self-legitimacy, supervisor support, COVID-19 information and adaptive emotion regulation were found to be associated with an enhanced level of mental health.

The surveys were conducted at the beginning of the community outbreak. Given the cross sectional nature of the data, the findings may not reflect officers' mental health at different phases of the pandemic.

Such study can add a cross-national perspective that can be utilized to generalize about policy perspectives related to police mental health at times of health crises, such as COVID-19 pandemic.

Einleitung Dieser Artikel hat den Zweck, den heutigen Stand des Wissens auf dem Gebiet der strategischen Führung auf die Fremdenverkehrsunternehmung zu übertragen. Zweck der folgenden Ausführungen ist' es, die Orientierungsgrössen der strategischen Führung in ihrem Zusammenhang darzustellen. Es soll gezeigt werden, dass die entsprechenden, bisher im industriellen Bereich erprobten Denkkategorien auch für Fremdenverkehrunternehmungen gültig und mit Nutzen auf diese anwendbar sind. lm Rahmen dieses Artikels können nicht alle für die Tourismusbranche spezifischen Gegebenheiten vollumfänglich berücksichtigt werden. Die theoretischen Ausführungen werden jedoch anhand von zahlreichen konkreten Beispielen aus dem Tourismus‐ und Freizeitsektor erläutert. Neben Beispielen aus Fremdenverkehrsunternehmungen im engeren Sinne werden auch solche aus Fremdenverkehrsorten dargestellt, bei denen es sich in bestimmter Hinsicht urn unternehmungsartige Gebilde 1) handelt.

System dynamics is a whole-system modelling and learning approach, useful for tackling non-linear problems, such as sustainable urban development. The purpose of this paper is to review system dynamics applications in the simulation of sustainable urban development over a period from 2005 to 2017.

The analysis reveals that the number of applications of system dynamics modelling in the area of urban sustainable development increased in the analysed period. Research has changed its focus from the modelling of environmental problems to more complex models, portraying the multidimensional socio-economic processes that have an impact on the sustainability of urban development. Analysed case studies most often use the behaviour reproduction test for model validation, but without a unified approach. In most cases, modelling has been done in China, Germany and the USA, while urban development in the Eastern European countries, Africa and Latin America has not often been investigated. This paper indicates the knowledge gaps and suggests future research directions.

Papers that report the use of system dynamics modelling reveal a wide range of applications in urban sustainability. The analysis shows significant emphasis on environmental problems, while the interest for modelling social problems has been increasing during the last several years. Most of the modelled problems examine the sustainability of resources (land, water) and waste management, which are used for insights into the reasons for the system behaviour, forecasting future behaviour and policy testing.

The presented models were developed in most cases for the purpose of understanding the phenomena examined, as well as the future use of the models in policy planning. This brings us back to the need for greater stakeholder involvement, not only in the initial phase, but also during the whole modelling process, which could increase understanding, use and ownership of the models in the future, and thus increase their practical application.

This study explored the effects of the coronavirus pandemic on rural municipal police in Pennsylvania.

The authors surveyed rural police chiefs and sworn officers to inquire about their intra-department organizational capabilities, police-community relations, well-being practices, and how these strategies may have developed since March 2020.

The pandemic affected rural police officers and rural policing strategies in many ways. Moreover, existing challenges to limited rural police budgets were exacerbated suggesting a need for more flexible budgetary capacities, access to wellness resources were limited suggesting better access to these resources and preparation for responding to public health emergencies was limited suggesting more complete training is warranted.

This study draws attention to the unique experiences of rural municipal police across one state by capturing specific areas of concern throughout the coronavirus pandemic.

The main purpose of this study is to explain the combined effects of host country weak network ties and absorptive capacity on the innovative foreign knowledge inflows of international high-tech small- and medium-sized enterprises (SMEs).

Data are drawn from the two largest and most authoritative German Federal Government census-databases of biotech and nanotech SMEs. A structured survey questionnaire was administered and regression analysis adopted.

This study demonstrates weak network ties in the host country and developing absorptive capacity produce a combined effect that positively influences international high-tech SMEs innovative foreign knowledge inflows. Also, host country weak network ties and absorptive capacity when considered separately, each respectively, positively influence innovative foreign knowledge inflows.

The results help inform key personnel in international high-tech SMEs about the relevance of host country weak network ties and absorptive capacity for foreign knowledge inflows. In addition, the results help policymakers and think-tanks to promote tailored advice and guidance e.g. those policymakers implementing the EU Entrepreneurship 2020 Action Plan.

There is a recent call in the literature to combine network theory and absorptive capacity theory to better explain knowledge creation in the context of international high-tech SMEs knowledge sourcing. By addressing this call, the study provides a more refined and comprehensive account of international high-tech SMEs innovative foreign knowledge inflows.

Das vorliegende Thema geht von einem Abhängigkeitsverhältnis zwischen Fremdenverkehr einerseits und Reiseform bzw. Reisegewohnheit andererseits ans. Begrifflich ist der Fremdenverkehr denn auch zu verstehen als «Inbegriff der Beziehungen und Erscheinungen, die sich aus der Reise und dem Aufenthalt Ortsfremder ergeben, sofern durch den Aufenthalt keine Niederlassung begründet und damit keine Erwerbstätigkeit verbunden wird». Mit andern Worten besteht der Fremdenverkehr aus einer dynamischen Komponente Reise und einer statischen Komponente Aufenthalt, wobei er sich, zunächst rein äusserlich betrachtet und deshalb im engsten Sinne, als Verkehrsvorgang präsentiert:

Das Feld Die Feldforschung als Teil der empirischen Sozial‐forschung geht vom Begriff des “Feldes” aus, einem abgegrenzten Datenreservoir, zu dem sich der Forscher direkten oder indirekten Zugang verschaffen kann (NOWOTNY und KNORR 1975). Wesentlich für die Feldforschung ist die Tatsache, dass die empirischen Untersuchungen nicht in einer Laborsituation sondern in situ durchgeführt werden (WEIDMANN 1971) und eine Kontrolle über die Variablen nicht oder nur in beschränktem Umfang (beim Feldexperiment) möglich ist. Da selbst bei einem äusserst eingeschränkten Forschungsgegen‐stand die Fülle aller erfassbaren Daten unüberseh‐bar würde, ist es notwendig, das Feld vor Untersuchungsbeginn abzugrenzen, d.h. Hypothesen über die geographische, ethnographische, zeitliche und soziologische Begrenzung und eventuell auch über vorhandene Strukturen und ihre Dynamik zu bilden, die mit den Methoden der Feldforschung bestätigt oder falsifiziert werden. Feldforschung unterliegt damit auch den Regeln der Hypothesenbildung in den induktiv vorgehenden empirischen Wissenschaften, wogegen nicht spricht, dass Feldforschung, welche überwiegend qualitative Ergebnisse liefert, selbst wiederum für die Hypothesenbildung und die Formulierung von Fragestellungen auf einer nächsten Stufe der Feldforschung verwendet wird, die unter Umständen eher quantifizierbare Ergebnisse bringt. Das Feld ist die komplexe Wirklichkeit der sozialen Verhaltensweisen und Prozesse, die in ihre natürlichen Umweltbedingungen eingebettet sind und in zum Teil höchst komplizierten Interaktionsverhältnissen stehen. Den Feldbegriff gibt es in anderer Form in den verschiedensten Wissenschaftsbereichen, insbe‐sondere in der auf LEWIN zurückgehenden Gestalt Psychologie, nach der das Verhalten eines Lebewesens durch die Bedingungen des Feldes oder Lebensraumes, in dem es erfolgt, bestimmt wird. Das Verhalten ist somit die Funktion eines Feldes, das diese Person umschliesst und miteinbezieht (LEWIN 1951). Auch in den Sprachwissenschaften wird der Begriff des Feldes als ein System definiert, in dem ein Wort oder eine grössere sprachliche Einheit einen bestimmten Platz hat und aus dem heraus die Bedeutung des Wortes oder dieser sprachlichen Einheit erarbeitet werden kann (GECKELER 1971). Allen wissenschaftlichen Feldbegriffen ist gleich, dass es sich um einen Bereich von Daten und ihre dynamische Verknüpfung untereinander handelt, deren Struktur mit wissenschaftlichen Methoden herausge‐arbeitet und nach Möglichkeit sogar operational gemacht werden kann.