An analysis of energy consumption and carbon footprints of cryptocurrencies and possible solutions

There is an urgent need to control global warming caused by humans to achieve a sustainable future.CO_(2) levels are rising steadily,and while countries worldwide are actively moving toward the sustainability goals proposed during the Paris Agreement in 2015,we are still a long way to go from achieving a sustainable mode of global operation.The increased popularity of cryptocurrencies since the introduction of Bitcoin in 2009 has been accompanied by an increasing trend in greenhouse gas emissions and high electrical energy consumption.Popular energy tracking studies(e.g.,Digiconomist and the Cambridge Bitcoin Energy Consumption Index(CBECI))have estimated energy consumption ranges from 29.96 TWh to 135.12 TWh and 26.41 TWh to 176.98 TWh,respectively for Bitcoin as of July 2021,which are equivalent to the energy consumption of countries such as Sweden and Thailand.The latest estimate by Digiconomist on carbon footprints shows a 64.18 MtCO_(2) emission by Bitcoin as of July 2021,close to the emissions by Greece and Oman.This review compiles estimates made by various studies from 2018 to 2021.We compare the energy consumption and carbon footprints of these cryptocurrencies with countries around the world and centralized transaction methods such as Visa.We identify the problems associated with cryptocurrencies and propose solutions that can help reduce their energy consumption and carbon footprints.Finally,we present case studies on cryptocurrency networks,namely,Ethereum 2.0 and Pi Network,with a discussion on how they can solve some of the challenges we have identified.

Carbon, Water, Ecological Footprints, Energy and Nutritional Densities of Omnivore and Vegan Culinary Preparations

This study aimed to evaluate energy and nutritional densities, water, carbon and ecological footprints, cost, of omnivorous and vegan main courses served in a university restaurant in the city of Rio de Janeiro. A cross-sectional, analytical study was conducted with 40 main dish-type preparations, 20 of which are omnivorous and 20 vegans, served at lunch, to assess energy and nutritional densities, carbon, water and ecological footprints and cost of preparations. We propose a healthy and sustainable preparation index (HSPI) to evaluate from the list, the best preparation options considering the nutritional quality combined with the impact that the food causes on the environment. Preparations with the highest HSPI were considered the best options because they have a good relation between the nutritional profile and the environmental impact. Results: Regarding energy (ED), nutritional (ND) densities and water, carbon and ecological footprints, omnivorous preparations presented much higher values when compared to the vegan ones. The omnivorous preparations had the highest average cost (R$ 3.44). Regarding the HSPI, vegan preparations showed better rates than omnivorous preparations. Food services should promote healthy and sustainable choices by offering menus with low energy density preparations, high nutritional density, and low environmental impact, considering local realities and customer needs. Conclusion: This study was able to evaluate the best preparation options, considering the nutritional profile and the food impact on the environment, using health and sustainable indicators. Obtaining indicators of preparations regarding healthiness and sustainability, in practice, translates environmental aspects in menu planning, which contribute to changes in food consumption patterns in food services, in addition to contributing to the reduction of the environmental impact. In this way, they can be used as tools added to the menu planning process for the analysis of the environmental impact of menus, in addition to nutritional and qualitative aspects.

Carbon footprints in minimally invasive surgery:Good patient outcomes,but costly for the environment

Advancements in technology and surgical training programs have increased the adaptability of minimally invasive surgery(MIS).Gastrointestinal MIS is superior to its open counterparts regarding post-operative morbidity and mortality.MIS has become the first-line surgical intervention for some types of gastrointestinal surgery,such as laparoscopic cholecystectomy and appendicectomy.Carbon dioxide(CO_(2))is the main gas used for insufflation in MIS.CO_(2)contributes 9%-26%of the greenhouse effect,resulting in global warming.The rise in global CO_(2)concentration since 2000 is about 20 ppm per decade,up to 10 times faster than any sustained rise in CO_(2)during the past 800000 years.Since 1970,there has been a steady yet worrying increase in average global temperature by 1.7℃ per century.A recent systematic review of the carbon footprint in MIS showed a range of 6-814 kg of CO_(2)emission per surgery,with higher CO_(2)emission following robotic compared to laparoscopic surgery.However,with superior benefits of MIS over open surgery,this poses an ethical dilemma to surgeons.A recent survey in the United Kingdom of 130 surgeons showed that the majority(94%)were concerned with climate change but felt that the lack of leadership was a barrier to improving environmental sustainability.Given the deleterious environmental effects of MIS,this study aims to summarize the trends of MIS and its carbon footprint,awareness and attitudes towards this issue,and efforts and challenges to ensuring environmental sustainability.

The calculation and analysis of ecological footprints,diversity and developm ent capacity of China

T he ecological footprint of China's provinces is calculated in this pap er. In general, China's development is not sustainable because its ecological footprint is beyond its bio-capacity. The sustainability status of each pr ovince in China is presented. Ulanowicz's development capacity formula w as introduced to discuss the relationship of development and ecological footprin t's diversity. The diversity of ecological impacts is related to the e fficiency with which an economy uses the source and sink services of the environment and, in this view, should be a factor in economic output. Developme nt capacity, calculated from the ecological footprint and its diversity , is used to examine the relationship of economic output with the st ructure of the ecological footprint. China and its provinces are prese nted as a case study to investigate this relationship. The analysis s hows that footprint capacity is significant in predicting economic outp ut. Increasing the ecological footprint's diversity is presented as another way to increase development capacity.

Research on Dinoasur Footprints in Zizhou, Shaanxi Province, China

In recent years, the discoveries of dinosaur footprints have been successively reported from Dianshi Town, Zizhou City, Shaanxi Province. The footprints include the tracks of theropod, ornithopod and sauropod as well. Actually, the dinosaur footprints were found by local inhabitants much earlier in history, but not for science. The slabs bearing the dinosaur footprints were collected for domestic use, such as building stones, millstones, cellar covers, sheepfold fences, windlass holders, etc. This paper is to describe the dinosaur footprints on both sides of three slabs used for cellar covers, sheepfold fences and windlass holders by the local people. 24 dinosaur footprints and 4 trackways have been recognized and all of them belong to theropod. Four kinds of dinosaur footprints are identified, including 1 new ichnogenus and 2 new ichnospecies： （1） Shanbeipus caudatus ichnogen, et ichnosp, nov.; （2） Pengxianpus yulinensis ichnosp, nov.; （3） Eubrontes ichnosp; （4） Kayentapus ichnosp. Dinosaur-footprint-bearing beds were initially identified as the Fuxian Formation of the Lower Jurassic. Multipal dinosaur footprints associated with fragment plant fossils suggest a humid fluviolacustrine environment setting in the Ordos Basin during the early period of the Jurassic.

Footprints of China Auto International Exhibition Tour

November 2008,the Sixth China Auto International(Algeria & Egypt)Exhibi- tion Tour is ready.Since the first session was held in 1995,the Chinese auto enterprises have been to Vietnam,Cambodia,Syria,and Russian.In the past five sessions,Chinese auto brands not only experienced the endless hardships,

Review and Outlook of China Electronic and IT Industry Footprints in IEC International Standardization Activities

Year 2006 is the year marking the 100th anniversary of the founding of International Electrotechnical Commission (IEC). IEC is mainly engaged in the international standardization for electrical and electronic technology field aiming at promoting international trade and technology cooperation and exchange, improving product and service quality, upgrading productivity and protecting the environment as well as human health and safety. Most countries worldwide adopt standards developed and promulgated by IEC, providing a platform to international trade and technical exchange. China has being a member since 1957. Electronic and IT are the most developed and energetic filed in recent decades. Number of IEC TC/SC specialized in electronic and IT amounts up to 52.……

A TRAIL-BLAZER'S FOOTPRINTS ——A biographic sketch of CAS member Li Yiyi

People will never forget a scene at the First National Conference of Model Workers held in 1959,when the No.1 blast furnace of the No.1 Steelworks under the Benxi Iron & Steel Corporation was named a national standard bearer of the Red Flag,with its productivity ratio having won the national championship.The story was reported by the People’s Daily,Soviet Women’s Journal and Benxi Daily.As the young leader of the cited team of furnacemen, Li Yiyi became known to all. Time flies by and 34 years have elapsed since then.

Coupling analysis of social-economic water consumption and its effects on the arid environments in Xinjiang of China based on the water and ecological footprints

In arid areas,ecological degradation aroused by over-exploitation of fresh water,expansion of artificial oasis and shrinkage of natural oasis,has drawn attention of many scholars and officials.The water and ecological footprints can be used to quantitatively evaluate the water consumption of social-economic activities and their influence on the eco-environments.In addition,increase of the water footprint indicates the expansion of artificial oasis,and the influence on the natural oasis could be reflected by the variation of the ecological footprint.This study was conducted to answer a scientific question that what is the quantitative relationship between the expansion of the artificial oasis and the degradation of the natural oasis in the arid environments of Xinjiang,China.Thus,based on the social-economic data,water consumption data and meteorological data during 2001–2015,we calculated the water and ecological footprints to express the human-related pressure exerted on the water resources and arid environments in Xinjiang(including 14 prefectures and cities),and explore the relationship between the water and ecological footprints and its mechanism by using the coupling analysis and Granger causality test.The results show that both the water and ecological footprints of Xinjiang increased significantly during 2001–2015,and the increasing rate of the ecological footprint was much faster than that of the water footprint.The coupling degree between the water and ecological footprints was relatively high at the temporal scale and varied at the spatial scale.Among the 14 prefectures and cities examined in Xinjiang,the greater social-economic development(such as in Karamay and Urumqi)was associated with the lower coupling degree between the two footprints.Increases in the water footprint will cause the ecological footprint to increase,such that a 1-unit increase in the consumption of water resources would lead to 2–3 units of ecological degradation.The quantitative relationship between the increases of the water and ecological footprints,together with the intensities of water consumption both in the natural and artificial oases of Tarim River Basin,have approved the fact that the formation and expansion of 1 unit of the artificial oasis would bring about the degradation of 2 units of the natural oasis.These conclusions not only provide a technical basis for sustainable development in Xinjiang,but also offer a theoretical guide and scientific information that could be used in similar arid areas around the world.

Wide/narrow azimuth acquisition footprints and their effects on seismic imaging

Acquisition footprint is a new concept to describe the seismic noise in three-dimensional seismic exploration and it is closely related to geometry and observation shuttering. At present, the study on acquisition footprints has become a hot spot. In partnership with the Dagang Oilfield, we used the channel sand body seismic physical model to study the characteristics of wide/narrow azimuth acquisition footprints and analyzed and compared the two types of footprints and their effects on target imaging. In addition, the footprints caused by data processing of the normal moveout offset （NMO） stretching aberration were discussed. These footprints are located only in the shallow or middle layer in the time slice, and possibly affect the imaging of shallow target layers, and have no influence on deep target imaging. Seismic physical modeling has its advantages in the study of acquisition footprints.

A fast computational method for the landing footprints of space-to-ground vehicles

Fast computation of the landing footprint of a space-to-ground vehicle is a basic requirement for the deployment of parking orbits, as well as for enabling decision makers to develop real-time programs of transfer trajectories. In order to address the usually slow computational time for the determination of the landing footprint of a space-to-ground vehicle under finite thrust, this work proposes a method that uses polynomial equations to describe the boundaries of the landing footprint and uses back propagation(BP) neural networks to quickly determine the landing footprint of the space-to-ground vehicle. First, given orbital parameters and a manoeuvre moment, the solution model of the landing footprint of a space-to-ground vehicle under finite thrust is established. Second, given arbitrary orbital parameters and an arbitrary manoeuvre moment, a fast computational model for the landing footprint of a space-to-ground vehicle based on BP neural networks is provided.Finally, the simulation results demonstrate that under the premise of ensuring accuracy, the proposed method can quickly determine the landing footprint of a space-to-ground vehicle with arbitrary orbital parameters and arbitrary manoeuvre moments. The proposed fast computational method for determining a landing footprint lays a foundation for the parking-orbit configuration and supports the design of real-time transfer trajectories.

Ecological Carrying Capacity of Tibet China ——Variety of Ecological Footprints from 1978 to 2002

Ecological footprint's theory and method are used to calculate and analysisthe ecological carrying capacity in Tibet. The results indicate: Tibet ecological footprint (2.1hm^2) keeps higher than countrywide average level (1.5 hm^2), and lower than global average level(2.4 hm^2); the result show that Tibet pasture ecological footprint is the most different with otherarea, and woodland is the second; Tibet ecological footprint grows from 1. 25 hm^2 in 1978 to 2.09hm^2 in 2002, which states that life level is improving continuously; GDP (per RMB 10~4 Yuan)ecological footprint reduces from 61. 9 hm^2 in 1978 to 4. 54 hm^2 in 2002, which states resourcesutilized ratio is increasing continuously.

Study on Ecological Footprints and Sustainable Development in Karst Area——Taking Anshun as an example

[ Objective] The aim was to study the ecological footprint and sustainable development in Karst Area. [ Method] By dint of statistical da- ta of Anshun City in 2008, the ecological footprint of Anshun City was calculated. The sustainable development of ecological system in Anshun City was analyzed from the angle of balance of supply and demand. [ Result] The per capita ecological capacity was 0.447 8 hm2/cap in 2008, per capi- ta ecological footprint was 2.309 0 hm2/cap, and ecological surplus of deficit was 1.861 2 hm2/cap. It meant the EF of the present region in terms of human activities had already exceeded the benchmark of system ecological carrying capacity. The supply of natural resources can＇t fully meet people＇s needs, and land use was unsustainable. The sustainable development of Karst area can be realized through changing people＇s production and life consumption model, building resources-saving social productive consumption system, depending scientific and technological development, improving production technology, using new technology, improving resources utilization effect and developing recycle economy. [Condusion] The study provided theoretical basis for sustainable development in Karst area.

A Conceptual Framework Evaluating Ecological Footprints and Monitoring Renewable Energy: Wind, Solar, Hydro, and Geothermal

With worldwide increases in energy consumption, and the need to increase reliance on renewable energy, we must examine ecological footprints of each energy source, as well as its carbon emissions. Renewable energy sources (wind, solar, hydro, geothermal) are given as the best examples of “green” energy sources with low carbon emissions. We provide a conceptual model for examining the ecological footprint of energy sources, and suggest that each resource needs continued monitoring to protect the environment, and ultimately human health. The effects and consequences of ecological footprint need to be considered in terms of four-compartments: underground (here defined as geoshed), surface, airshed, and atmosphere. We propose a set of measurement endpoints (metrics may vary), in addition to CO2 footprint, that are essential to evaluate the ecological and human health consequences of different energy types. These include traditional media monitoring (air, water, soil), as well as ecological footprints. Monitoring human perceptions of energy sources is also important for energy policy, which evolves with changes in population density, technologies, and economic consequences. While some assessment endpoints are specific to some energy sectors, others can provide crosscutting information allowing the public, communities and governments to make decisions about energy policy and sustainability.

Reduced Ecological Footprints of Modern Facilities Introducing the Implementation of Advanced Wireless Technologies, and Human Resources’ Benefits

The necessity of lowering the mean power consumption of various facilities, due to the lack of their enormous future energy needs, led to an ongoing advance of various technologies. These technologies have been oriented towards the concept of a Reduced Ecological Footprint. Massive structures (such as building complexes and hospitals) have been redesigned and upgraded;many interior designs have been dramatically altered while new electronic devices are constantly being produced in order to revolutionize a long term perspective towards a “Green Planet” while they exhibit astonishing signal processing. Consequently, an enormous technology already exists which needs to be properly combined to a proposed methodology and to new ideas relevant to systems’ administration through automatic wireless control. This paper intends to reduce the gap between design and realization of the aforementioned research. Consequently, the primary contribution of this research is the proposal of a complete design protocol with minimized defects relevant to Reduced Ecological Footprints of Facilities (REFF) along with its beneficial advantages relevant to providing a healthy and productive work environment. This protocol consists of four main parts which are 1) the main key points-guidelines, 2) its objectives, 3) the know-how methodology for implementation in existing installations and 4) the description of the imminent benefits in workforce/human resources.

Carbon and Nitrogen Footprints of Major Cereal Crop Production in China:A Study Based on Farm Management Surveys

Greenhouse gas(GHG)emissions and reactive nitrogen(Nr)releases are central environmental problems,which are closely linked to climate change,environmental ecology and crop production.Sustainable development of agriculture plays an important role in GHG emissions and Nr loss.The life cycle assessment(LCA)method was used to calculate the product and farm carbon footprints(CFs)and nitrogen footprints(NFs)in rice,wheat and maize production in China based on farm survey data.The results pinpointed that the CFs of rice,wheat and maize were 0.87,0.30 and 0.24 kg/kg.Meanwhile,the computed NFs were 17.11,14.26 and 6.83 g/kg,respectively.Synthetic nitrogen fertilizer applications and methane(CH4)emissions were dominant CF sources,while ammonia(NH3)volatilization was the main NF contributor.Moreover,significant decreases in CF and NF by 20%–54%and 33%–61%,respectively,were found in large-size farms(>20 hm^(2))when compared to small-size farms(<0.7 hm^(2)).Furthermore,the significantly positive relationships between CF and NF indicated the potential for simultaneous mitigation in the regions with high agricultural inputs,like amounts of fertilizer.Based on our results,some effective solutions would be favorable toward mitigating climate change and eutrophication of the major cereal crop production in China,especially optimizing fertilizer use and farm machinery operation efficiencies,as well as developing large-size farms with intensive farming.

Knowledge and Perceptions of Energy Alternatives, Carbon and Spatial Footprints, and Future Energy Preferences within a University Community in Northeastern US

Our overall research aim was to examine whether people distinguished between the spatial footprint and carbon footprint of different energy sources, and whether their overall “worry” about energy types was related to future developed of these types. We surveyed 451 people within a university community regarding knowledge about different energy sources with regard to renewability and spatial and carbon footprints and attitudes about which energy type(s) should be developed further. Findings were: 1) Gas, oil and coal were rated as the least renewable, and wind, solar and hydro as the most renewable;2) Oil and coal were rated as having the largest carbon footprint, while wind, solar and tidal were rated the lowest;3) There were smaller differences in ratings for spatial footprints, probably reflecting unfamiliarity with the concept, although oil and gas were rated the highest;4) Energy sources viewed as renewable were favored for future development compared with non-renewable energy sources, and coal and oil were rated the lowest;5) Worry-free sources such as solar were favored;and 6) There were some age-related differences, but they were small, and there were no gender-related differences. Overall, subjects knew more about carbon footprints than spatial footprints, generally correctly identified renewable and non-renewable sources, and wanted future energy development for energy sources which were less worried about (e.g. solar, wind). These perceptions require in-depth examination in a large sample from different areas of the country.

Blue and Grey Water Footprints of Dairy Farms in Kuwait

In Kuwait, dairy farming faces challenges due to its significant water demands. The current study assessed seasonal patterns of water use to estimate the blue water footprint (WF) and grey WF per kg of fat protein corrected milk (FPCM) for confined dairy farming systems in Kuwait. Blue and grey WFs were evaluated using data from three operational farms. The average blue WF (L·kg-1 FPCM) was estimated to be 54.5 ± 4.0 L·kg-1 in summer and 19.2 ± 0.8 L·kg-1 in winter. The average grey WF (generated from milk house wastewater) was assessed on bimonthly basis and determined based on its phosphate (PO4) concentration (82.2 ± 14.3 mg·L-1) which is the most limiting factor to be 23.0 ± 9.0 L·kg-1 FPCM d-1. The outcomes indicate that enhancing the performance of dairy cows and adopting alternative water management strategies can play a role in minimizing the impacts of confined dairy farming systems in Kuwait on water quality and quantity.

Water pollution footprints induced by industrial import and export in China

With the rapid development of foreign trade in China, industrial import and export has been an absolute subject in recent years. The huge trade surplus of import and export trade of industrial products brings not only high profits, but also pollution costs as well. Based on the concept of water pollution footprints(WPFs), this study applies the input-output method and calculates pollutant-producing coefficients of 20 major industrial sectors in China and investigates the WPFs caused by the import and export trades of these industrial sectors. The research results show that WPF resulting from exports exceeds that of imports from 2011 to 2015 in China. The net inflow of pollution footprint is mainly from paper mills, printing and stationery manufacturing, and textile industry; whereas a great number of WPFs are transferred to other countries by these sectors,such as metal mining and dressing industry and oil and natural gas exploitation industry.