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The Coast to Karoo Transect investigates the abundance and diversity of ants and beetles along an altitudinal gradient in the Cederberg mountains of the Western Cape, South Africa. It is a long term project, initiated in 2002 by Prof. S.L. Chown, Stellenbosch University. Data collection is carried out on a biannual (spring and autumn) basis. To monitor changes in invertebrate assemblages, focusing on ants and beetles. Temperature data are collected with i-buttons and a Hobo data logger.

This is a complementary dataset associated with the following publication: Berrang-Ford, Lea, et al. "Systematic Mapping of Global Research on Climate and Health Using Machine Learning." The Lancet Planetary Health. Meta-data are included.

MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014 ; An ever-expanding global industry focuses attention on energy supply and use. Cost-effective electrical energy production and reduced consumption pave the way for this expansion. Eskom’s demand-side management (DSM) initiative provides the opportunity for reduced electricity consumption with cost-effective implementation for their respective clients. South African gold mines have to extend their operations to up to 4000 m below the surface to maintain profitable operations. Deep-level mining therefore requires large and energy-intensive cooling installations to provide safe working conditions. These installations generally consist of industrial chillers, cooling towers, bulk air coolers and water transport systems. All of these components operate in unison to provide chilled service water and cooled ventilation air underground. In this study the improved energy efficiency and control of a South African gold mine’s cooling plant is investigated. The plant is separated into a primary and secondary cooling load, resulting in a cascading cooling system. Necessary research was conducted to determine the optimal solution to improve the plant’s performance and electrical energy usage. Variable speed drives (VSD) were installed on the chiller evaporator and condenser water pumps to provide variable flow control of the water through the chillers, resulting in reduced motor electricity usage. Potential electricity savings were simulated. Proposed savings were estimated at 600 kW (13.6%) daily, with an expected saving of R 2 275 000 yearly, resulting in a payback period of less than 9 months. Results indicated are based on total savings, as VSD savings and control savings were combined. The VSDs that were installed, were controlled according to an optimum simulation model’s philosophy. A real-time energy management program was used to control the VSDs and monitor the respective systems. The program’s remote capabilities allow for off-site ...

The Soutpansberg Transect investigates the abundance and diversity of ants and spiders along an altitudinal gradient in the Western Soutpansberg Mountains, South Africa. It has a north-south orientation over the mountain and is a long term project initiated in 2009. Data collection is carried out in intervals that suit the data logger capacity. To study the diversity patterns in ants and other invertebrate groups across the spatial transect over a long-term period and the climate the invertebrates.

Climate change will alter both temperature and moisture availability in the future and therefore will likely affect vector borne disease prevalence. Organisms faced with changes in weather can respond in a variety of ways and this complicates any predictions and inferences for these organisms with climate change. Cause-and-effect links between climate change, insect vector responses, and changes in risk of disease transmission are poorly established for most vector borne diseases. Tsetse (Diptera, Glossinidae) are important vectors of trypanosome parasites posing a major threat to human health and socio-economic welfare in Africa. Water balance plays an important role in determining activity patterns, energy budgets, survival and population dynamics and, hence, geographic distribution and abundance of insects. Glossina species occupy a wide range of habitats in Africa and are notable for their desiccation resistance in xeric environments. Yet, whether or not the different species, subgroups or ecotype groups differ in susceptibility to changes in weather remain undetermined. Submitted in partial fulfilment of the requirements for the degree Master of AgriScience in Conservation Ecology

Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2016. ; Power fluctuations in a microgrid are caused by disturbances due to the connection and disconnection of Distributed Generators (DG’s), as well as the irregular input of the sun and wind renewable energy. Renewable penetration such as the sun, wind and tidal energy causes intermittency which directly affects the input and resultant output power of a microgrid. Control systems have to be implemented on three different levels to ensure the stability and reliability of the power supplied to the load. This can be achieved by implementing the following: 1) Primary control with mechanical valves and actuators to translate feedback signals through droop control. 2) Secondary control with power electronics to facilitate maximum power point tracking, phase lock loops and switch mode inverters to manipulate the electrical signals to a desired set points including PID control. 3) Tertiary control with software program management to monitor the power flow as well as to evaluate congregated logic and implement decision making. Energy storage systems like super capacitors can compensate for power imbalance by providing excess stored energy to the microgrid for short periods of time. The added advantage of capacitor banks is that it can facilitate power factor correction where inductive loads like rotating motors form large part of the total load. Battery banks can compensate for energy shortage for longer periods of time. The duration of the compensation can be determined by the size, topology and the type of batteries used. The objectives of this study is to improve the unstable power output responses of a renewable energy microgrid by designing and analysing control strategies intended at power wavering compensation which also includes energy storage. Sub control systems is created and simulated in Matlab/Simulink for analytical comparative observations. Results of the simulated model are discussed and recommendations are given for future works.

L'Assemblée générale des Nations Unies en septembre 2021 réunira les pays à un moment critique pour organiser une action collective pour faire face à la crise environnementale mondiale. Ils se réuniront à nouveau lors du sommet sur la biodiversité à Kunming, en Chine, et de la conférence sur le climat (COP26) à Glasgow, au Royaume-Uni. Avant ces réunions cruciales, nous, rédacteurs en chef de revues de santé du monde entier, appelons à une action urgente pour maintenir l'augmentation moyenne de la température mondiale en dessous de 1,5 ° C, mettre fin à la destruction de la nature et protéger la santé. La Asamblea General de la ONU en septiembre de 2021 reunirá a los países en un momento crítico para organizar la acción colectiva para abordar la crisis ambiental mundial. Se reunirán de nuevo en la cumbre de biodiversidad en Kunming, China, y en la conferencia sobre el clima (COP26) en Glasgow, Reino Unido. Antes de estas reuniones fundamentales, nosotros, los editores de revistas de salud de todo el mundo, pedimos medidas urgentes para mantener el aumento promedio de la temperatura global por debajo de 1,5 ° C, detener la destrucción de la naturaleza y proteger la salud. The UN General Assembly in September 2021 will bring countries together at a critical time for marshalling collective action to tackle the global environmental crisis. They will meet again at the biodiversity summit in Kunming, China, and the climate conference (COP26) in Glasgow, UK. Ahead of these pivotal meetings, we-the editors of health journals worldwide-call for urgent action to keep average global temperature increases below 1.5°C, halt the destruction of nature, and protect health. ستجمع الجمعية العامة للأمم المتحدة في سبتمبر 2021 البلدان في وقت حرج لحشد العمل الجماعي لمعالجة الأزمة البيئية العالمية. وسيجتمعون مرة أخرى في قمة التنوع البيولوجي في كونمينغ، الصين، ومؤتمر المناخ (COP26) في غلاسكو، المملكة المتحدة. قبل هذه الاجتماعات المحورية، ندعو - نحن محرري المجلات الصحية في جميع أنحاء العالم - إلى اتخاذ إجراءات عاجلة للحفاظ على متوسط الزيادات في درجات الحرارة العالمية أقل من 1.5 درجة مئوية، ووقف تدمير الطبيعة، وحماية الصحة.

La relaxation par ultrasons des verres de tellurite xB2O3 – 70 TeO2 – (30 – x) WO3, 0 ≤ x ≤ 30 mol% a été étudiée en mesurant l'atténuation par ultrasons (αL) dans ces verres dans la gamme thermique 140–300 K (T) à diverses fréquences (f). Certaines caractéristiques peuvent être obtenues à partir de la relation de αL–T, telles que l'énergie d'activation moyenne (Ep) et la fréquence de tentative (f0). Les variables Ep et f0 sont fonction de la fréquence et de la teneur en B2O3. De plus, la relation αL–T rend bien compte des oscillations des atomes d'oxygène dans un processus de relaxation. Un tel processus physique provient de la transmission d'énergie ultrasonore aux atomes d'oxygène oscillants dans un potentiel à double puits. Le processus de relaxation est inspecté par un modèle appelé force centrale 1. Les différentes variables physiques soustraites d'un tel modèle sont fonction du contenu B2O3. La relajación ultrasónica de los vidrios de telurito xB2O3 – 70 TeO2 – (30 – x) WO3, 0 ≤ x ≤ 30 mol% se investigó midiendo la atenuación ultrasónica (αL) en estos vidrios en el rango térmico 140–300 K (T) a varias frecuencias (f). Algunas características se pueden obtener de la relación de αL–T, como la energía de activación media (Ep) y la frecuencia de intento (f0). Las variables Ep y f0 son una función de la frecuencia y el contenido de B2O3. Además, la relación αL–T explica bien las oscilaciones de los átomos de oxígeno en un proceso de relajación. Dicho proceso físico se origina a partir de la transmisión de energía ultrasónica a los átomos de oxígeno oscilantes en un potencial de doble pozo. El proceso de relajación es inspeccionado por un modelo llamado fuerza central uno. Las diferentes variables físicas restadas de dicho modelo son una función del contenido de B2O3. The ultrasonic relaxation of tellurite glasses xB2O3 – 70 TeO2 – (30 – x) WO3, 0 ≤ x ≤ 30 mol% was investigated by measuring the ultrasonic attenuation (αL) in these glasses in the thermal range 140–300 K (T) at various frequencies (f). Some characteristics can be obtained from the relation of αL–T, such as the average activation energy (Ep) and the attempt frequency (f0). The variables Ep and f0 are a function of frequency and B2O3 content. Moreover, the relation αL–T accounts well for the oscillations of the oxygen atoms in a relaxation process. Such a physical process is originated from transmitting ultrasonic energy to the oscillating oxygen atoms in a dual-well potential. The relaxation process is inspected by a model named central force one. The subtracted different physical variables from such a model are a function of B2O3 content. تم فحص الاسترخاء بالموجات فوق الصوتية لنظارات التيلوريت xB2O3 – 70 TeO2 – (30 – x) WO3، 0 ≤ x ≤ 30 mol% من خلال قياس التوهين بالموجات فوق الصوتية (αL) في هذه النظارات في النطاق الحراري 140–300 K (T) عند ترددات مختلفة (f). يمكن الحصول على بعض الخصائص من علاقة αL - T، مثل متوسط طاقة التنشيط (Ep) وتردد المحاولة (f0). المتغيران Ep و f0 هما دالة للتردد ومحتوى B2O3. علاوة على ذلك، فإن العلاقة αL - T تمثل بشكل جيد تذبذبات ذرات الأكسجين في عملية الاسترخاء. تنشأ هذه العملية الفيزيائية من نقل الطاقة فوق الصوتية إلى ذرات الأكسجين المتذبذبة في جهد بئر مزدوج. يتم فحص عملية الاسترخاء بواسطة نموذج يسمى القوة المركزية الأولى. المتغيرات الفيزيائية المختلفة المطروحة من هذا النموذج هي دالة لمحتوى B2O3.