scholarly journals Measurement and Analysis of Urban Total Factor Energy Efficiency in China

2021 ◽  
Vol 261 ◽  
pp. 01020
Author(s):  
Feifei Lu ◽  
Yinling Lu ◽  
Na Lei
Keyword(s):  
Energy Efficiency ◽  
Technological Progress ◽  
High Efficiency ◽  
Malmquist Index ◽  
Coastal Areas ◽  
Central China ◽  
Measurement And Analysis ◽  
Urban Energy ◽  
Research Objects ◽  
Low Efficiency

The improvement of urban energy efficiency is of great significance to reduce carbon emissions and achieve China’s goal of carbon peak in 2030. Taking 266 cities as the research objects, the energy efficiency of each city is measured by Super-SBM model. Then the energy efficiency is decomposed by Malmquist index. The results show that: In 2006, the number of cities in high-efficiency areas is small and high efficiency areas are mostly distributed in the northeast and southeast coastal areas. There was a phenomenon of low efficiency areas agglomeration. But in 2017, the number of high-efficiency cities increased significantly. The number of high-efficiency cities in Northeast China increased, the number of high-efficiency cities in Southeast coastal areas decreased, and the number of high-efficiency cities in Central China increased and showed a phenomenon of agglomeration of high-efficiency areas or relatively high efficiency areas. According to the decomposition of urban energy efficiency, technological progress is the main driving force for the improvement of energy efficiency, and the decline of technical efficiency inhibits the improvement of energy efficiency in various cities.

scholarly journals Evaluating the Carbon Emissions Efficiency of the Logistics Industry Based on a Super-SBM Model and the Malmquist Index from a Strong Transportation Strategy Perspective in China

2020 ◽  
Vol 17 (22) ◽  
pp. 8459
Author(s):  
Xiaohong Jiang ◽  
Jianxiao Ma ◽  
Huizhe Zhu ◽  
Xiucheng Guo ◽  
Zhaoguo Huang
Keyword(s):  
Carbon Emissions ◽  
Growth Rates ◽  
Carbon Emission ◽  
High Efficiency ◽  
Malmquist Index ◽  
Logistics Industry ◽  
Sbm Model ◽  
Low Efficiency ◽  
Emission Growth ◽  
Second Category

Carbon emissions from the logistics industry have been rising year after year. Correct handling of the relationship between economic development and environmental protection is of great significance to the implementation of green logistics, which is an important component of China’s strategy for strong transportation. This paper focuses on the evaluation of the carbon emissions efficiency of logistics industry from a new strong transportation strategy perspective. A super-efficiency slack-based measurement (Super-SBM) model and Malmquist index are combined to evaluate the static and dynamic carbon emissions efficiency of the logistics industry. The results indicate that compared with the SBM model, the Super-SBM model can more effectively measure the carbon emissions efficiency of the logistics industry. Pilot regions for the strong transportation strategy were divided into two categories, namely regions with slow carbon emission growth rates but high efficiency, and regions with high carbon emission growth rates but low efficiency. Some policy recommendations from the strong transportation strategy perspective were proposed to improve the carbon emissions efficiency of the logistics industry, especially for the second category of pilot regions. This study is expected to provide a basis for decision-making for efficient emissions reduction measures and policies, and to encourage the pilot regions to take the lead in achieving the goal of China’s strategy for transportation.

Measurement and Analysis on Energy Efficiency of Elevators in Shanghai

2014 ◽  
Author(s):  
Wu Hao ◽  
Chang Xiaoqing ◽  
Xue Jiai
Keyword(s):  
Energy Efficiency ◽  
Influence Factors ◽  
Electricity Consumption ◽  
Classification Method ◽  
The Past ◽  
Measurement And Analysis ◽  
The World ◽  
New Energy ◽  
Policy Measures ◽  
Research Objects

Shanghai is the largest city of elevators in the world with 165000 elevators and escalators. According to latest research, elevators typically account for about 3% to 8% of the overall electricity consumption of a building. Therefore, it is significantly to study the energy efficiency of elevators in Shanghai. However, elevators have received little attention from an efficiency perspective in the past. To recover this gap, this paper analyses classification method on energy efficiency of elevators in Shanghai and suggests policy measures for energy conservation. First, Representative elevators in Shanghai were collected as research objects; second, a new energy efficiency classification method was established on the modification of VDI4707 according to actual situations in China, then, energy consumption of these elevators were measured and classified according to the new method. Finally, the influence factors of elevator energy efficiency were studied, and suggestion on the improvement of the energy efficiency of elevators in Shanghai was given.

scholarly journals Spatial–Temporal Heterogeneity and the Related Influencing Factors of Tourism Efficiency in China

2021 ◽  
Vol 13 (11) ◽  
pp. 5825
Author(s):  
Zhiliang Liu ◽  
Chengpeng Lu ◽  
Jinhuang Mao ◽  
Dongqi Sun ◽  
Hengji Li ◽  
...  
Keyword(s):  
Spatial Pattern ◽  
Influencing Factors ◽  
High Efficiency ◽  
Southern China ◽  
Malmquist Index ◽  
Northern China ◽  
Tourism Industry ◽  
Environmental Cost ◽  
Resource Endowment ◽  
Low Efficiency

Tourism efficiency is an effective index of measuring the development quality of the tourism industry. In this study, the tourism efficiency of 30 provinces in China during the period from 2006 to 2018 was measured with the SBM model and Malmquist index. On the basis of ESDA and GWR models, we explored the spatial pattern of China’s tourism efficiency and the spatial heterogeneity of the influencing factors in depth. The results revealed that China’s tourism efficiency has been constantly enhanced with an increasingly balanced pattern. Meanwhile, the utilization degrees of various input factors have constantly been improving. Both technological efficiency and technological progress jointly promote rapid growth of total-factor productivity. Accompanied with constant enhancement of the spatial agglomeration effect, the local spatial pattern also showed obvious differentiation. In general, low-efficiency regions were mainly concentrated in northern China, while high-efficiency regions were concentrated in southern China. The distinct spatial–temporal differentiation characteristics of tourist economic efficiency can be attributed to different influencing strengths of various factors in various regions and different action tendencies. The level of economic development, traffic conditions, the professional level of tourism, and openness degree can significantly promote tourism efficiency. Tourism resource endowment and environmental cost impose slight effects and differ in action direction, thereby inhibiting the tourism efficiency of many regions.

Drying and heating of scrap metal at steelmaking: industrial safety, economics, ecology

2020 ◽  
Vol 76 (12) ◽  
pp. 1353-1258
Author(s):  
V. A. Spirin ◽  
V. E. Nikol’skii ◽  
D. V. Vokhmintsev ◽  
A. A. Moiseev ◽  
P. G. Smirnov ◽  
...  
Keyword(s):  
Energy Efficiency ◽  
High Efficiency ◽  
Steel Production ◽  
Scrap Metal ◽  
Industrial Safety ◽  
Technical Solution ◽  
Metal Charge ◽  
Basic Task ◽  
Scrap Heating ◽  
Winter Time

At steel production based on scrap metal utilization, the scrap heating before charging into a melting facility is an important way of energy efficiency increase and ecological parameters improving. In winter time scrap metal charging with ice inclusions into a metal melt can result in a considerable damage of equipment and even accidents. Therefore, scrap preliminary drying is necessary to provide industrial safety. It was shown, that in countries with warm and low-snow climate with no risk of scrap metal icing up during its transportation and storing in the open air, the basic task being solved at the scrap drying is an increase of energy efficiency of steelmaking. InRussiathe scrap metal drying first of all provides the safety of the process and next - energy saving. Existing technologies of scrap metal drying and heating considered, as well as advantages and drawbacks of technical solutions used at Russian steel plants. In winter time during scrap metal heating at conveyers (Consteel process) hot gases penetrate not effectively into its mass, the heat is not enough for evaporation of wetness in the metal charge. At scrap heating by the furnace gases, a problem of dioxines emissions elimination arises. Application of shaft heaters results in high efficiency of scrap heating. However, under conditions of Russian winter the upper scrap layers are not always heated higher 0 °С and after getting into a furnace bath the upper scrap layers cause periodical vapor explosions. The shaft heaters create optimal conditions for dioxines formation, which emit into atmosphere. It was shown, that accounting Russian economic and nature conditions, the metal charge drying and heating in modified charging buckets by the heat of burnt natural gas or other additional fuel is optimal. The proposed technical solution enables to burnt off organic impurities ecologically safely, to melt down ice, to evaporate the wetness in the scrap as well as to heat the charge as enough as the charging logistics enables it. The method was implemented at several Russian steel plants. Technical and economical indices of scrap metal drying in buckets under conditions of EAF-based shop, containing two furnaces ДСП-100, presented.

scholarly journals CHROMOSOMAL BASIS OF THE MEROZYGOSITY IN A PARTIALLY DIPLOID MUTANT OF PNEUMOCOCCUS

Genetics ◽  
1975 ◽  
Vol 80 (4) ◽  
pp. 667-678
Author(s):  
Mary Lee S Ledbetter ◽  
Rollin D Hotchkiss
Keyword(s):  
High Efficiency ◽  
Point Mutations ◽  
Resistant Mutant ◽  
Chromosomal Marker ◽  
Structural Abnormality ◽  
C Cells ◽  
Wild Type ◽  
Chromosomal Locus ◽  
Low Efficiency ◽  
Derivatives Of

ABSTRACT A sulfonamide-resistant mutant of pneumococcus, sulr-c, displays a genetic instability, regularly segregating to wild type. DNA extracts of derivatives of the strain possess transforming activities for both the mutant and wild-type alleles, establishing that the strain is a partial diploid. The linkage of sulr-c to strr-61, a stable chromosomal marker, was established, thus defining a chromosomal locus for sulr-c. DNA isolated from sulr-c cells transforms two mutant recipient strains at the same low efficiency as it does a wild-type recipient, although the mutant property of these strains makes them capable of integrating classical "low-efficiency" donor markers equally as efficiently as "high efficiency" markers. Hence sulr-c must have a different basis for its low efficiency than do classical low efficiency point mutations. We suggest that the DNA in the region of the sulr-c mutation has a structural abnormality which leads both to its frequent segregation during growth and its difficulty in efficiently mediating genetic transformation.

scholarly journals A Brief Review on Solvent-Free Synthesis of Zeolites

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 788
Author(s):  
Jinlin Mei ◽  
Aijun Duan ◽  
Xilong Wang
Keyword(s):  
High Efficiency ◽  
Raw Materials ◽  
Solvent Free ◽  
High Yield ◽  
Control Synthesis ◽  
Mechanical Mixing ◽  
Synthesis Mechanism ◽  
Wastewater Pollution ◽  
Low Efficiency ◽  
Solvent Free Synthesis

The traditional hydrothermal method to prepare zeolite will inevitably use a large amount of water as a solvent, which will lead to higher autogenous pressure, low efficiency, and wastewater pollution. The solvent-free method can be used to synthesize various types of zeolites by mechanical mixing, grinding, and heating of solid raw materials, which exhibits the apparent advantages of high yield, low pollution, and high efficiency. This review mainly introduces the development process of solvent-free synthesis, preparation of hierarchical zeolite, morphology control, synthesis mechanism and applications of solvent-free methods. It can be believed that solvent-free methods will become a research focus and have enormous industrial application potential.

scholarly journals Inflight Transmission of COVID-19 Based on Experimental Aerosol Dispersion Data

2021 ◽  
Author(s):  
Zhaozhi Wang ◽  
Edwin R Galea ◽  
Angus Grandison ◽  
John Ewer ◽  
Fuchen Jia
Keyword(s):  
High Efficiency ◽  
Face Mask ◽  
Generation Rate ◽  
Aviation Industry ◽  
Filtration System ◽  
Dispersion Data ◽  
Low Probability ◽  
Meal Service ◽  
Low Efficiency ◽  
Aerosol Dispersion

Abstract Background An issue of concern to the travelling public is the possibility of in-flight transmission of COVID-19 during long- and short-haul flights. The aviation industry maintains that the probability of contracting the illness is small based on reported cases, modelling and data from aerosol dispersion experiments conducted on-board aircraft. Methods Using experimentally derived aerosol dispersion data for a B777–200 aircraft and a modified version of the Wells-Riley equation we estimate inflight infection probability for a range of scenarios involving quanta generation rate and face mask efficiency. Quanta generation rates were selected based on COVID-19 events reported in the literature while mask efficiency was determined from the aerosol dispersion experiments. Results The MID-AFT cabin exhibits the highest infection probability. The calculated maximum individual infection probability (without masks) for a 2-hour flight in this section varies from 4.5% for the ‘Mild Scenario’ to 60.2% for the ‘Severe Scenario’ although the corresponding average infection probability varies from 0.1% to 2.5%. For a 12-hour flight, the corresponding maximum individual infection probability varies from 24.1% to 99.6% and the average infection probability varies from 0.8% to 10.8%. If all passengers wear face masks throughout the 12-hour flight, the average infection probability can be reduced by approximately 73%/32% for high/low efficiency masks. If face masks are worn by all passengers except during a one-hour meal service, the average infection probability is increased by 59%/8% compared to the situation where the mask is not removed. Conclusions This analysis has demonstrated that while there is a significant reduction in aerosol concentration due to the nature of the cabin ventilation and filtration system, this does not necessarily mean that there is a low probability or risk of in-flight infection. However, mask wearing, particularly high-efficiency ones, significantly reduces this risk.

scholarly journals High Efficiency Generalized Parallel Counters for Look-Up Table Based FPGAs

2015 ◽  
Vol 2015 ◽  
pp. 1-16 ◽  
Author(s):  
Burhan Khurshid ◽  
Roohie Naaz Mir
Keyword(s):  
Power Dissipation ◽  
High Speed ◽  
High Efficiency ◽  
Critical Path ◽  
Fir Filters ◽  
Path Delay ◽  
Look Up Table ◽  
Improved Performance ◽  
Ip Cores ◽  
Low Efficiency

Generalized parallel counters (GPCs) are used in constructing high speed compressor trees. Prior work has focused on utilizing the fast carry chain and mapping the logic onto Look-Up Tables (LUTs). This mapping is not optimal in the sense that the LUT fabric is not fully utilized. This results in low efficiency GPCs. In this work, we present a heuristic that efficiently maps the GPC logic onto the LUT fabric. We have used our heuristic on various GPCs and have achieved an improvement in efficiency ranging from 33% to 100% in most of the cases. Experimental results using Xilinx 5th-, 6th-, and 7th-generation FPGAs and Stratix IV and V devices from Altera show a considerable reduction in resources utilization and dynamic power dissipation, for almost the same critical path delay. We have also implemented GPC-based FIR filters on 7th-generation Xilinx FPGAs using our proposed heuristic and compared their performance against conventional implementations. Implementations based on our heuristic show improved performance. Comparisons are also made against filters based on integrated DSP blocks and inherent IP cores from Xilinx. The results show that the proposed heuristic provides performance that is comparable to the structures based on these specialized resources.

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