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Disorder plays an essential role in shaping the transport properties of GeSbTe phase-change materials (PCMs) to enable nonvolatile memory technology. Recently, increasing efforts have been undertaken to investigate disorder in the stable hexagonal phase of GeSbTe compounds, focusing on a special type of swapping bilayer defects. This configuration has been claimed to be the key element for a new mechanism for phase-change memory. Here, we report a direct atomic-scale chemical identification of these swapping bilayer defects in hexagonal GeSb2Te4together with nanoscale atomic modeling and simulations. We identify the intermixing of Sb and Te in the bilayer to be the essential ingredient for the stability of the defects, and elucidate their abundance as due to the small energy cost. The bilayer defects are demonstrated to be ineffective in altering the electron localization nature that is relevant to transport properties of hexagonal GeSb2Te4. Our work paves the way for future studies of layer-switching dynamics in GeSbTe at the atomic and electronic level, which could be important to understand the new switching mechanism relevant to interfacial phase-change memory.

The invention of floatovoltaic technologies brought new meaning to the theoretical framing of sustainability as the technology delivers extended natural resource conservation benefits. However, planning assessments for this novel sustainable energy technology exposed knowledge gaps jeopardising global financial investments and regulatory approvals. Knowledge and methodological gaps cause inaccurate performance predictions in current geospatial-engineering modelling tools and fail to adequately quantify the diverse range of layered performance qualities and impacts of floating photovoltaics. This paper advances a geo-sensitive system dynamics framework to systemically integrate the energy, environmental and economic domain object functions in characterising the behaviour and sustainability of floating photovoltaic systems theoretically. The framework serves as computer logic in a geospatial digital twin to synthesise floatovoltaic operations to predict the technology’s sustainability impact and offset attributes in balanced scorecard metrics and water–energy–land–food nexus indicators. Experimental evaluations with the proposed framework in a real-world setting demonstrate the value of the holistically integrated framework in analytical floatovoltaic project appraisal and planning support. The results highlight significant advantages when comparing a 1000 m2floatovoltaic system with a similar-sized conventional photovoltaic alternative, including a 19.3% lifetime energy gain, a carbon emission displacement of CO2e=5168t and a freshwater evaporation benefit of 983 kL. Predictive energy, environmental and economic modelling also offers water–energy–land–food–resource analysis parameters, thus delivering multi-attribute performance profiles that solve many of the current problems with the “technology unknowns” of floatovoltaics that impede energy project commissioning and licensing approvals.

According to the of approximately 4.5 billion dollars for the entire economy are anticipated. However, all these 'future' estimates of losses for Pakistan do not consider past adaptations by the farmers in their calculations and thus tend to overestimate climate change induced losses. This paper contributes to the literature by studying the effectiveness of households' adaptation and coping measures regarding the prevention of loss and damage using choice-modelling. In order to assess, whether loss and damage is likely to occur in future and to determine, whether crop-cultivating farmers have well adapted, simulations are run. Farmers are found to adjust their crop choices considering climate and expected income. If farmers adapt, benefits exceeding 300 million dollars are possible for the crop sector. In the business as usual scenario, losses between 4 and 12 million dollars (2030/2090) are found. The findings hint towards well-directed adaptations of farmers in Pakistan, preventing loss and damage.

Forensic mapping has been used successfully in South Africa to bring criminals to book. This article discusses four examples of forensic mapping applications used in courts as evidence ranging from murder, kidnapping to stock theft. These four cases necessitated various approaches to display the information in court. A single map was used in the first case example. In the second murder case example, a storyboard approach was used to portray the events surrounding the murder. Several maps in a presentation format were used to illustrate the suspects' involvement in stock theft. The last example consisted of a report that included several maps to indicate the suspects' involvement in the crime. The conclusion is that the mapping approach must be appropriate for a specific court case to convey the evidence as clear possible to the court.

This paper describes an analytical and experimental investigation of the dynamic response and performance of a special type of centrifugal pendulum vibration absorber used for reducing torsional vibrations in rotating systems. This absorber has the property that it behaves linearly out to large amplitudes, and thus experiences no frequency detuning. Previous analytical work on such tautochronic absorbers has considered the response, dynamic stability, and performance of single- and multi-absorber systems. In particular, it is known that these absorbers, when perfectly tuned to the order of the applied torque, do not exhibit hysteretic jumps in the response, but multi-absorber systems can experience instabilities that destroy the symmetry of their synchronous response. In this work we extend the theory to include linear de-tuning of the absorbers, which can be used as a design parameter to influence absorber performance, both in terms of rotor vibration reduction and operating range. This paper reviews the basic analysis, which employs scaling and averaging, and extends it to include the detuning. In addition, systematic experiments of systems with one and two absorbers are carried out. The experimental results are unique in that the test facility is capable of varying the excitation order, thereby allowing one to obtain order-response curves that are useful for design purposes. The experimental results are found to be in excellent agreement with the analytical predictions, and these clearly demonstrate the tradeoffs faced when selecting absorber tuning.

The structures as well as the genesis of the C5H7O2+ions from some different ethylenacetal derivatives have been established. It is shown that the title ions do not isomerize to a common intermediate or a mixture of equilibrating structures prior to or during collisional activation.

A novel, thermogravimetric TG method is demonstrated for the quantitative determination of a dispersed active phase on a γ-Al2O3catalytic support.

BackgroundFloods are a disaster situation for all affected populations and especially for vulnerable groups within communities such as children, orphans, women, and people with chronic diseases such as HIV and AIDS. They need functioning health care, sanitation and hygiene, safe water, and healthy food supply, and are critically dependent on their social care and support networks. A study carried out in the Ohangwena region, Namibia, where HIV prevalence is high and extensive flooding frequently occurs, aims to provide a deeper understanding of the impact that flooding has on people living with HIV (PLWHIV) as well as on HIV service providers in the region.DesignThe qualitative research applying grounded theory included semi-structured interviews with PLWHIV, focus group discussions with HIV service providers, and a national feedback meeting. The findings were interpreted using the sustainable livelihoods framework, the natural hazard research approach, and health behaviour theories.ResultsThe study reveals that flooding poses major problems to PLWHIV in terms of their everyday lives, affecting livelihoods, work, income, and living conditions. The factors threatening them under normal conditions – poverty, malnutrition, unsafe water, sanitation and hygiene, limited access to health facilities, a weak health status, and stigma – are intensified by flood-related breakdown of infrastructure, insecurity, malnutrition, and diseases evolving over the course of a flood. A potential dual risk exists for their health: the increased risk both of infection and disease due to the inaccessibility of health services and antiretroviral treatment. A HIV and Flooding Frameworkwas developed to display the results.ConclusionsThis study demonstrates that vulnerabilities and health risks of PLWHIV will increase in a disaster situation like flooding if access to HIV prevention, treatment, care and support are not addressed and ensured. The findings and the HIV and Flooding Frameworkare not specific to Ohangwena and can be transferred to any flood-affected region that has a high HIV prevalence and relies mainly on subsistence agriculture. They serve as a model case for analysing vulnerabilities related to health and health service provision under disaster conditions. The impact will vary according to the physical, geographical, climatological, social, and behavioural characteristics of the region and the people affected. In the Ohangwena region, a disaster risk management mechanism is already in place which addresses people with HIV during flooding. However, preparedness could be improved further by applying the HIV and Flooding Framework.

The purpose of this study is to investigate the impact of the sugar market policy of the European Community (EC) on developing countries. This problem is of special relevance, since on the one hand the EC's sugar market is its most protected agricultural market and, on the other hand, a special trade preference in the form of the EC sugar protocol is given to some developing countries. The study starts with a quantification of the effect of the EC sugar policy on world market prices for sugar and the implied transfer effects for selected developing countries. The analysis of the sugar protocol allows one to apply a method to calculate the maximum transfer effects due to this agreement. It is shown that the producttied transfers are completely arbitrary and do not respond to any official objective of EC development policy. Nevertheless, the agreement may allow the EC to buy a maximum of goodwill on the side of developing countries with a given cost.

This article examines the effects of the EC price-fixing in EC agricultural policy on the stability of producers' revenue. First, a stochastic market model is developed to point out determinants of the effects of the EC agricultural price policy on the coefficient of variation of producers' revenue. A simulation approach is then derived to measure the short-term effects of EC price-fixing on the instability of producers' revenue at the EC level and for the Fed. Rep. of Germany. It is applied to the EC sugar policy using information of a presented econometric estimation of export supply and import demand in the world sugar market.