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Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0–5 and 5–15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (−0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications.
Gait analysis is a systematic study of human movement. Combining wearable foot pressure sensors and machine learning (ML) solutions for a high-fidelity body pose tracking from RGB video frames could reveal more insights into gait abnormalities. However, accurate detection of heel strike (HS) and toe-off (TO) events is crucial to compute interpretable gait parameters. In this work, we present an experimental platform to study the timing of gait events using a new wearable foot pressure sensor (ActiSense System, IEE S.A., Luxembourg), and Google’s open-source ML solution MediaPipe Pose. For this purpose, two StereoPi systems were built to capture stereoscopic videos and images in real time. MediaPipe Pose was applied to the synchronized StereoPi cameras, and two algorithms (ALs) were developed to detect HS and TO events for gait and analysis. Preliminary results from a healthy subject walking on a treadmill show a mean relative deviation across all time spans of less than 4% for the ActiSense device and less than 16% for AL2 (33% for AL1) employing MediaPipe Pose on StereoPi videos. Finally, this work offers a platform for the development of sensor- and video-based ALs to automatically identify the timing of gait events in healthy individuals and those with gait disorders.
Since tangible assets of companies are becoming increasingly insignificant, emphasis should rather be placed on human capital as an essential source of competitive edge. This paper, accordingly, pursues the purpose to shed light on the major demands that the Millenials place on their prospective employers. In consequence, the work aims to identify attractiveness factors that German retailers should particularly promote in order to succeed in the war for talents and attract the most promising candidates among the German Gen Y. This work is based on a mixed-methods approach. First, interviews with German retail experts as well as generational keynote speakers were conducted in order to obtain a deep understanding and assessment of the German retail landscape from a professional perspective. The insights gained were subsequently used to design a questionnaire, which distribution led to a final sample of 216 useable responses by Millenials. Furthermore, the data obtained by interviewing experts and the survey was subsequently compared in order to evaluate to what extent the expectations of the Millenials correspond to the experts’ assessment. This study reveals Millenials to be driven by the need for growth, such as wide offers of development opportunities or scope for decision when choosing an employer. Among the relatedness needs, a harmonious working environment is particularly important, whereas a weekend off ranks first among the existential needs. Moreover, male Millenials consider Media Markt being the most popular employer in the German retail sector, while dm is preferred from a female perspective. Overall, employers of the German retail sector provide the majority of factors required by the Millenials, yet are only considered the 4th most popular industry behind the automotive, IT, art and entertainment industries. Our findings provide valuable practical implications as the research results might serve companies to build up a target group specific employer brand. Marketing strategies can be aligned with the identified attractiveness factors to efficiently and cost-effectively attract and bind Millenials to the company. Customized recruiting campaigns enhance the appeal as well as the attractiveness of an employer driving the likelihood of obtaining the strived status: Employer of Choice. To the best of the author’s knowledge, no study has yet dealt specifically with the attractiveness factors demanded by the Millenials in the context of the German retail sector as well as their most aspired employers in this industry. Furthermore, the attractiveness factors identified in the literature were embedded in Aldefer’s ERG theory. This work also offers a bilateral perspective through the widely conducted survey carried out among Millenials, which was additionally expanded through the lens of experts.
Purpose: Grounded in the theoretical concepts of utilitarianism and deontology, this paper aims to evaluate the issue of child labour from an ethics perspective. By linking utilitarianism with normative stakeholder theory, relevant stakeholder groups are being identified in order to examine their influence on and role in the occurrence of child labour allowing for a practical reference. The findings may serve companies in particular as a basis for decision-making in the development of their value chains.
Design/Methodology/Approach: The author uses a literature review in order to analyze the findings of existing literature on the topic of child labour in an ethics context, thereby drawing on literature, indexed in Web of Science and Google Scholar by employing forward and backward citation analysis.
Findings: The investigation of child labour in terms of ethics yields conflicting results. From a deontological perspective, child labour can never be ethical and should always be rejected as it is not wanted to become a general law. In contrast, according to a utilitarian sentiment, child labour is ethically justifiable as long as the beneficiaries of the labour are greater in number than the children working or suffering.
Originality/Value: The examination of child labour from the perspective of deontology and utilitarianism in conjunction with normative stakeholder theory constitutes a novelty in the ethics literature. The integration of theoretical findings into a practical business context provides additional value for managers and global supply chain managers.
The dark side of Samsung’s value chain: The human costs of cobalt mining “BLOOD, SWEAT AND COBALT”
(2021)
Samsung has been implicitly linked to human rights abuses and wider social downgrading propagated within the Democratic Republic of Congo (DRC). Reports by different studies have shown artisanal cobalt mines (ASM) to exploit child labour and subject workers to perilous conditions. The IT multinational is dependent upon Congolese cobalt as a key element in lithiumion batteries used to produce their array of electronics. However, irresponsible cobalt sourcing practices undertaken by Tier 1 suppliers, Glencore and Huayou, have resulted in ASM operations being incorporated into Samsung’s global value chain, as Tier 2 suppliers. Analysis of the relationships underpinning Samsung’s cobalt value chain theoretical framework, highlights the presence of a relational governance structure, with captive elements among upstream Tier 1 and Tier 2 suppliers. Samsung is thereby reliant upon both Glencore and Huayou to transmit and enforce private codes of conduct down the value chain to expel human rights abuses. In conjunction, the DRC’s weak and unstable institutional environment has facilitated corruption and the improper enforcement of laws across the ASM industry. It is thereby imperative that Samsung takes ownership of the issues present within its value chain, as both Tier 1 suppliers and the Congolese government have failed to ensure responsible cobalt sourcing practices to date. This report recommends that Samsung adopt a holistic action plan, not only utilising their own resources and capabilities, but also those of critical stakeholders including Tier 1 suppliers, NGOs and the DRC and South Korean governments. Most prominently, this report suggests that supply chain transparency can be improved using certificates of origin and blockchain technology. Furthermore, it is recommended that poverty alleviation is targeted as a key measure through “Cobalt for Development”, an action plan designed to instigate both social and economic upgrading within ASM operations and the wider community. By employing a multi-scalar approach and addressing the issues inherent across multiple governance levels, Samsung can ensure a responsible source of cobalt be sustained.
Containerization is one of the most important topics for modern data centers and web developers. Since the number of containers on one- and multi-node systems is growing, knowledge about the energy consumption behavior of single web-service containers is essential in order to save energy and, of course, money. In this article, we are going to show how the energy consumption behavior of single containerized web services/web apps changes while creating replicas of the service in order to scale and balance the web service.
Context: In the framework of studying cosmic microwave background polarization and characterizing its Galactic foregrounds, the angular power spectrum analysis of the thermal dust polarization map has led to intriguing evidence of an E/B asymmetry and a positive TE correlation. The interpretation of these observations is the subject of theoretical and simulation-driven studies in which the correlation between the density structure of the interstellar medium (ISM) and the magnetic field appears to be a key aspect. In this context, and when the magnetized ISM structures are modeled in three dimensions, dust clouds are generally considered to be filamentary structures only, but both filamentary and sheet-like shapes are supported by observational and theoretical evidence.
Aims: We aim to study the influence of the cloud shape and its connection to the local magnetic field, as well as the influence from the viewing angle, on the angular power spectra measured on thermal dust polarization maps; we specifically focus on the dependence of the E/B power asymmetry and TE correlation.
Methods: To this end, we simulated realistic interstellar clouds with both filament-like and sheet-like shapes using the software ASTERION, which also allowed us to generate synthetic maps of thermal dust polarized emission with an area of 400 square degrees. Then, we computed their polarization power spectra in the multipole range ℓ ϵ [100, 500] and focused on the E/B power asymmetry, quantified through the ℛEB ratio, and the correlation coefficient rTE between Τ and Ε modes. We quantified the dependence of ℛEB and rTE values on the offset angle (between the longest cloud axis and local magnetic field lines) and inclination angle (between the line of sight and the magnetic field) for both types of cloud shapes, either embedded in a regular magnetic field or coupled to a nonregular field to mimic turbulence.
Results: We find that both types of cloud shapes cover the same regions of the (ℛEB, rTE) parameter space. The dependence on the inclination and offset angles is similar for both shapes, although sheet-like structures generally show larger scatter than filamentary structures. In addition to the known dependence on the offset angle, we find a strong dependence of ℛEB and rTE on the inclination angle.
Conclusions: The very fact that filament-like and sheet-like structures may lead to polarization power spectra with similar (ℛEB,rTE) values complicates their interpretation. We argue that interpreting them solely in terms of filament characteristics is risky, and in future analyses, this degeneracy should be accounted for, as should the connection to the magnetic field geometry. Our results based on maps of 400 square degrees clarify that the overall geometrical arrangement of the magnetized ISM surrounding the observer leaves its marks on polarization power spectra.
For the assessment of human reaction time, a test environment was developed. This system consists of an embedded device with organic light-emitting diode (OLED) displays with push buttons for the combined presentation of visual stimulation and registration of the haptic human reaction. The test leader can define the test sequence with the aid of a graphical user interface (GUI) on a personal computer (PC). The validation of the system was proved by measuring the latency times of the whole system, which are conditioned by the specific hard- and software constellation. Through the investigation of the display’s light radiation by a photodiode and the recorded current consumption, latency times and their variance were specified. In the fastest mode the system can reach an error limit of 60 μs.
The photo-Dember effect is a source of impulsive THz emission following femtosecond pulsed optical excitation. This emission results from the ultrafast spatial separation of electron-hole pairs in strong carrier gradients due to their different diffusion coefficients. The associated time dependent polarization is oriented perpendicular to the excited surface which is inaptly for efficient out coupling of THz radiation. We propose a scheme for generating strong carrier gradients parallel to the excited surface. The resulting photo-Dember currents are oriented in the same direction and emit THz radiation into the favorable direction perpendicular to the surface. This effect is demonstrated for GaAs and In(0.53)Ga(0.47)As. Surprisingly the photo-Dember THz emitters provide higher bandwidth than photoconductive emitters. Multiplexing of phase coherent photo-Dember currents by periodically tailoring the photoexcited spatial carrier distribution gives rise to a strongly enhanced THz emission, which reaches electric field amplitudes comparable to a high-efficiency externally biased photoconductive emitter.
Global vernetzte Supply Chains (SC) führen bei den Unternehmen zu geringeren Kosten, aber zugleich erhöhen diese auch die Abhängigkeit ggü. den Lieferanten und die Störanfälligkeit der SCs wird erhöht. In den vergangenen Jahren haben zudem die Unsicherheiten für die SCs stark zugenommen. Treiber waren hier u.a. der Brexit, Handelskonflikte oder auch die Corona-Pandemie. In diesem Zusammenhang steht verstärkt die Entwicklung neuer SC-Strategien im Fokus der Unternehmen. Dabei wird stark auf die Verbesserung der Resilienz der SCs geachtet, um dadurch u.a. die Risiken für die SCs zu reduzieren. Die Arbeit beschäftigt sich mit den Auswirkungen steigender Unsicherheiten auf das Design sowie die Resilienz von SCs und hat das Ziel zu ermitteln, ob es Änderungen in der SC bedarf, um auf die Auswirkungen steigender Unsicherheiten zu reagieren und wie die Resilienz zukünftig sichergestellt werden kann (Trade-off zwischen Resilienz und Kosteneffizienz). Im Rahmen der Untersuchung erfolgte eine qualitative Forschung in Form von Experteninterviews, da so u.a. spezifische Meinungen oder auch Begründungen und Einstellungen von bestimmten Personen zu den vorliegenden Thematiken ermittelt werden können. Die Ergebnisse zeigen, dass die Kosten weiterhin meist der entscheidende Aspekt sind und es mehr Transparenz, Flexibilität sowie ein besseres Risikomanagement nötig ist. Des Weiteren bedarf es zukünftig u.a. einer größeren Berücksichtigung von Unsicherheiten, eine Erhöhung von Sicherheitsbeständen sowie eine Verringerung der Komplexität der SCs und u.U. mehr Local Sourcing. Es empfiehlt sich eine weitere Untersuchung hinsichtlich der Kosten, die durch Resilienz-Instrumente sowie durch fehlende Resilienz entstehen können, durchzuführen.