Empowerment Mechanisms and Empirical Evidence of Payment Technology in Capacity Expansion and Quality Improvement of Residents’Consumption

The time-varying difference-in-difference model is used to identify the impact of payment technology on residents’consumption,and the moderation effect analysis method is used to identify its mechanism.It is found that payment technology promotes consumption capacity expansion and quality improvement(CEQI)through three pathways of alleviating liquidity constraints,reducing transaction costs and weakening the payment of pain.The parallel and serial mechanisms of the three are further explored.The effect of payment technology on the CEQI of residents’consumption shows obvious heterogeneity due to differences in urban and rural household registration and financial literacy.Based on the empirical research results and the national conditions of China,targeted policy recommendations are proposed from the demand side,the supply side and the technological side.

Real-Time Tunable Gas Sensing Platform Based on SnO_(2) Nanoparticles Activated by Blue Micro-Light-Emitting Diodes

Micro-light-emitting diodes(μLEDs)have gained significant interest as an activation source for gas sensors owing to their advantages,including room temperature operation and low power consumption.However,despite these benefits,challenges still exist such as a limited range of detectable gases and slow response.In this study,we present a blueμLED-integrated light-activated gas sensor array based on SnO_(2)nanoparticles(NPs)that exhibit excellent sensitivity,tunable selectivity,and rapid detection with micro-watt level power consumption.The optimal power forμLED is observed at the highest gas response,supported by finite-difference time-domain simulation.Additionally,we first report the visible light-activated selective detection of reducing gases using noble metal-decorated SnO_(2)NPs.The noble metals induce catalytic interaction with reducing gases,clearly distinguishing NH3,H2,and C2H5OH.Real-time gas monitoring based on a fully hardwareimplemented light-activated sensing array was demonstrated,opening up new avenues for advancements in light-activated electronic nose technologies.

Modeling and optimization of a multi-carrier renewable energy system for zero-energy consumption buildings

For the carbon-neutral,a multi-carrier renewable energy system(MRES),driven by the wind,solar and geothermal,was considered as an effective solution to mitigate CO2emissions and reduce energy usage in the building sector.A proper sizing method was essential for achieving the desired 100%renewable energy system of resources.This paper presented a bi-objective optimization formulation for sizing the MRES using a constrained genetic algorithm(GA)coupled with the loss of power supply probability(LPSP)method to achieve the minimal cost of the system and the reliability of the system to the load real time requirement.An optimization App has been developed in MATLAB environment to offer a user-friendly interface and output the optimized design parameters when given the load demand.A case study of a swimming pool building was used to demonstrate the process of the proposed design method.Compared to the conventional distributed energy system,the MRES is feasible with a lower annual total cost(ATC).Additionally,the ATC decreases as the power supply reliability of the renewable system decreases.There is a decrease of 24%of the annual total cost when the power supply probability is equal to 8%compared to the baseline case with 0%power supply probability.

Analysis of Medical Waste Incinerator Performance Based on Fuel Consumption and Cycle Times

A detailed assessment of an incinerator based on fuel consumption and cycle time data is presented in this paper. The study was conducted at Temeke district hospital for 22 months consecutively covering 654 days of daily data collection on fuel consumption and cycle times. The composition for the medical waste incinerated varied between 15% and 35% for sharps waste and between 65% and 85% for other waste, with mean values of 25% and 75%, respectively. The results revealed poor performance of the incinerator due to higher fuel consumption (above 30 L/cycle). The incineration cycle times were observed to range between 2 and 4 hours, all of which were too high for the loading rates observed (55 - 214 kg). A strong dependency of diesel oil consumption on cycle time was observed due to lack of temperature control leading to continuous fuel flow into the burners. The incineration capacity was very low compared to other incinerators in terms of tons per year. This paper gives an insight on the factors affecting incinerator performance assessed based on diesel oil consumption and cycle times. It can be generalized that the incinerator performance was poor due to several factors ranging from poor incinerator design, operator skills, waste management practices, waste storage practices, etc. The hospital was advised to install a new incinerator with short incineration cycle time (30 - 40 minutes) and lower fuel consumption (10 L/cycle) at a loading rate of 200 kg/cycle.

Estimating model for urban carrying capacity on bike-sharing

As the demand for bike-sharing has been increasing,the oversupply problem of bike-sharing has occurred,which leads to the waste of resources and disturbance of the urban environment.In order to regulate the supply volume of bike-sharing reasonably,an estimating model was proposed to quantify the urban carrying capacity(UCC)for bike-sharing through the demand data.In this way,the maximum supply volume of bike-sharing that a city can accommodate can be obtained.The UCC on bike-sharing is reflected in the road network carrying capacity(RNCC)and parking facilities’carrying capacity(PFCC).The space-time consumption method and density-based spatial clustering of application with noise(DBSCAN)algorithm were used to explore the RNCC and PFCC for bike-sharing.Combined with the users’demand,the urban load ratio on bike-sharing can be evaluated to judge whether the UCC can meet users’demand,so that the supply volume of bike-sharing and distribution of the related facilities can be adjusted accordingly.The application of the model was carried out by estimating the UCC and load ratio of each traffic analysis zone in Nanjing,China.Compared with the field survey data,the effect of the proposed algorithm was verified.

Forecast and analysis of the "roof effect" of world net oil-exporting capacity

Oil is extremely crucial to the development of the modern economy. It is important to forecast the oil supply capacity due to its scarcity and non-renewability. This paper attempts to forecast and analyze thirty-five current and potential net oil-exporting countries. Integrating both qualitative and quantitative methods, the oil production and consumption are predicted based on historical data, so that the world net oil-exporting capacity can be obtained. The results show that the ＂roof effect＂ of the world net oil-exporting capacity may appear before 2030. Unconventional oil will play an important role in the future world oil market. The competition and cooperation relationships between OPEC and non-OPEC will last for a long time.

MIMO Spectral Efficiency over Energy Consumption Requirements: Application to WSNs

This paper presents the evaluation of the “capacity to the total energy consumption per bit ratio” of multiple antennas systems with distributed fashion. We propose an adequate geometric channel modeling for the wireless communication system which operates in indoor propagation environment with scatterers. The channel model is derived in function of both the line of sight (LOS) and the non line of sight (NLOS) components. The aim of this paper is to study the limits in the gain concerning the capacity to the total energy consumption ratio when additional antennas are implemented in the communication system. To do so, we have evaluated by simulations both the capacity and the total energy consumption per bit. Then, we have determined the capacity to the total energy consumption ratio. Finally, the computational capacity to the total energy ratio is obtained for different system configurations. We have shown that the gain in capacity increases with the number of antennas but it stills be limited by the total energy consumption. The limits for increasing the number of transmit antennas are determined in function of the separation distances between the transmitter and the receiver sides of the communication system. Optimal power allocation strategy via water-filling algorithm has been carried out for evaluating the capacity to energy ratio. We find by simulation that optimal power allocation brings a gain in the addressed metric reaching a level of about 1.7 at transmit signal to noise ratio of 8 dB if comparing to the case when transmit energy is equally split among transmit antennas.

Ecological footprint of food consumption in China:1982-2004

This paper calculates the land (including water area) requirement for food consumption in both balanced andactual diet in China by ecological footprint analysis. To determine whether logical and actual food demands are withinnatural regenerative ability, carrying capacity (excluding forestry production) is also calculated. Results show that actualdiet patterns were ecologically friendly in the period of 1982-2004 in China, mainly because of the rural moderate dietpatterns. But actual per capita footprint already overran its corresponding logic value of 0.976ha in urban areas in 2002.Productive areas for food production can satisfy the land requirement for actual diet patterns during the researchingperiod in China, nevertheless cannot satisfy that for balanced diet pattern or solve the problem of unbalanced ecologicalfootprint. The continual rising ecological footprint of food consumption in both rural and urban areas indicates that percapita footprint will keep on increasing in China and even may be more than the suggested logic value if no relevantcountermeasures are made to regulate diet patterns. Strictly speaking, China is facing food shortage, both in quality andin quantity.

Hand rim wheelchair training: Effects of intensity and duration on physical capacity

The purpose of this study was to compare the effects of intensity and duration of training on physical capacity in a 7 weeks hand rim wheelchair training in able-bodied men. Thirty-six able-bodied men participated in three groups: a 30% heart rate reserve (HRR) 70 min training group (N = 14), a 70% HRR 30 minutes training group (N = 13) and a 30% HRR 30 minutes training group (N = 9). All groups trained 3 times per week for 7 weeks on a treadmill. Pre and post tests on a wheelchair ergometer comprised a submaximal test at 20% and 40% of the estimated peak power output, in which submaximal heart rate, oxygen uptake and mechanical efficiency were determined. In maximal exercise tests, maximal isometric strength, sprint power, peak power output and peak oxygen uptake were measured. No significant differences were found between the training groups on submaximal and maximal parameters. It can be concluded that, in persons new to wheelchair use, seven weeks of wheelchair endurance training at an intensity of 30% HRR for 30 minutes is as effective as a training at a higher intensity (70% HRR) or with a longer duration (70 min).

Priority-Based Real-Time Stream Coding over Multi-Channel with Packet Erasures

Multi-channel can be used to provide higher transmission ability to the bandwidth-intensive and delay-sensitive real-time streams. However, traditional channel capacity theories and coding schemes are seldom designed for the real-time streams with strict delay constraint, especially in multi-channel context. This paper considers a real-time stream system, where real-time messages with different importance should be transmitted through several packet erasure channels, and be decoded by the receiver within a fixed delay. Based on window erasure channels and i.i.d.(identically and independently distributed) erasure channels, we derive the Multi-channel Real-time Stream Transmission(MRST) capacity models for Symmetric Real-time(SR) streams and Asymmetric Real-time(AR) streams respectively. Moreover, for window erasures, a Maximum Equilibrium Intra-session Code(MEIC) is presented for SR and AR streams, and is shown able to asymptotically achieve the theoretical MRST capacity. For i.i.d. erasures, we propose an Adaptive Maximum Equilibrium Intra-session Code(AMEIC), and then prove AMEIC can closely approach the MRST transmission capacity. Finally, the performances of the proposed codes are verified by simulations.

Study on Ecological Carrying Capacity of Land in Henan Province

In order to explore the technical methods to improve the ecological carrying capacity of regional land under the premise of limited land use area,an open ecological footprint model is established based on the traditional ecological footprint model.Using the two models,this paper evaluates the ecological carrying capacity of Henan Province in 2017.The results indicate that the ecological productive footprint of cultivated land in Henan Province is much larger than the ecological carrying capacity,but the ecological consumption footprint is lower than the ecological carrying capacity.The open ecological footprint model can clearly distinguish the internal and the external ecological consumption footprint after corrected by the consumption adjustment coefficient and the land-use structure adjustment coefficient.Based on the open ecological footprint model,the ecological carrying capacity evaluation results of Henan Province are more realistic.The comprehensive ecological carrying capacity in Henan Province has a surplus,but there are significant differences among different land use types.The cultivated land has the largest ecological carrying capacity surplus,while the fossil energy land has a larger ecological carrying capacity deficit.In the process of achieving sustainable development,Henan Province should focus on reducing energy consumption and improving the ecological carrying capacity of fossil energy land.The paper concludes that the open ecological footprint model can simulate the ecological carrying capacity under different land use structures and different consumption structures.According to the simulation results,the technical methods to improve the ecological carrying capacity under the premise of limited land use scale can be proposed.The research can provide reference for land use structure adjustment,land use planning and land protection in Henan Province.It can also provide scientific basis for ecological protection and high-quality development of the Yellow River basin.

基于Kriging模型的锥形气体静压轴承优化设计

针对如何提升小孔节流式锥形气体静压轴承综合性能的问题,以气浮电主轴用锥形气体静压轴承承载力最大、气体消耗量最小为优化目标,考虑轴承尺寸和工况要求的约束条件,采用最优拉丁超立方法选取设计点,通过有限元法计算样本集,利用2种提高精度的加点策略构建针对优化目标的改进Kriging代理模型,最终使用非支配排序遗传算法获得最优解集。根据工况要求,通过权重系数法提出了3种优化方案,优化方案的气体消耗量分别降低至初始设计的28.85%,56.08%和73.87%;承载力则分别提升至初始设计的1.14,2.16和2.44倍;3种优化方案在中高转速下的性能提升会更加明显。另外,提高轴承锥度虽然能提升承载力,但同时也会增加气体消耗量。

配电网高比例新能源极限消纳容量精准估计

高比例新能源接入配电网会导致潮流具有不确定性,新能源极限消纳容量估计精准度不高。针对该问题,提出了配电网高比例新能源极限消纳容量精准估计方法。确定反映高比例新能源出力大小和波动特性的物理量,分析不同天气条件下的高比例新能源出力特性。构建高比例新能源接入配电网网络模型,计算当前消纳容量以及高比例新能源接入节点的电压越限风险,将其与设定的电压越限标准阈值对比,得到极限消纳容量精准估计结果。实验结果表明,所提方法估计出的极限消纳容量数值与实验数据之间仅存在最大为200 kVA的误差,说明该方法的估计结果更为精准。

基于多目标平衡优化器的共享储能容量优化

随着绿色能源的大量投入使用,对储能装置的需求也相应增加,要求按比例配套投入,以有效应对电网供需双侧的不确定性,这带来了投资成本过高和回收周期过长的问题。为了应对绿色能源广泛应用带来的储能挑战,提出了一种多微电网储能装置共享模型,旨在显著减少整体储能容量的需求。为实现这一目标,设计了一种双层优化方法,并提出了一种多目标平衡优化器用以求解上层模型,避免结果陷入局部最优。通过数据实验验证,与传统的分布式储能方式相比,多微电网储能装置共享模型使系统所需的储能容量降低了43.30%。同时,算法对比结果表明,所提多目标优化算法具有足够的竞争力。

考虑风光消纳的风光核储混合系统容量优化

本研究主要通过多目标进化算法对风光核储混合能源系统进行容量优化配置。混合能源系统包括光伏电池、风机、小型模块化钍基熔盐堆(smTMSR),以及蓄热系统等。以提高供电稳定性、减小发电成本、降低弃电率(ECP)和提高可再生能源在整个供电系统的出力占比(可再生能源占比(REF))为目标,选择光伏容量、风机容量,以及蓄热系统容量作为优化参数,并选取武威市当地的气象数据作为输入参数,通过对非支配排序遗传算法Ⅱ,Ⅲ(NSGA-Ⅱ,NSGA-Ⅲ),以及强度帕累托进化算法(SPEA-SDE)性能的比较,选择较优的算法对多目标优化问题进行求解得到帕累托解集。通过基于指标相关性的指标权重确定(CRITIC)方法确定目标权重,采用理想解排序法(TOPSIS)对得到的帕累托解进行排序,从而选择最佳折中解。结果表明NSGA-Ⅱ相较于其他算法收敛速度最快,但解集均匀性较差。NSGA-Ⅲ尽管收敛速度较慢,但相较于其他算法其解集均匀性最好。优化结果显示最优容量配置功率供应缺失率(DPSP)为0.9686%,平准化电力成本(LCOE)为0.0857美元(/kW·h),ECP为4.8986%,REF为21.2589%。其中弃电量主要来自核电弃电,可再生能源弃电量较少。敏感性分析结果表明:光伏容量对DPSP,ECP及REF的影响最为显著,风机容量对LCOE的影响最为显著。风光核储混合能源系统可有效促进可再生能源消纳,保证了系统供电的稳定性。

2023年国内外油气行业发展及2024年展望

2023年,全球能源格局深刻调整,绿色低碳转型稳步推进;国际油价波动下跌,天然气价高位回落;油气勘探开发投资保持增长,油气产量继续双增;炼油乙烯产能继续增长,毛利总体下滑;大石油公司重新强化油气上游,降碳和盈利并重;碳减排共识进一步凝聚,碳市场影响力不断增强。中国油气行业立足安全清洁发展,能源行业政策体系加快完善;新型能源体系建设有序推进;成品油和天然气消费恢复向好,“全国一张网”加速完善;油气产储量保持增长,“两深一非”成增储上产新阵地;炼油能力继续小幅增长;大宗石化产品产能呈扩张态势;碳市场建设步伐加快。2024年,预计国际石油市场基本面由紧平衡转为供应过剩,天然气市场延续脆弱平衡,地缘政治紧张局势及外溢影响等将继续推动油气价格大幅波动;能源转型更加理性务实,基于安全效益发展建设能源韧性体系渐成共识。国内经济景气度回升势头向好,将进一步带动能源行业回暖;深化能源体制机制改革、加快建设新型能源体系、保障能源供应安全稳定仍是能源行业的重要使命任务。

考虑水风光联合发电效益最大的水电站水库优化调度

为了经济合理地充分发挥水电站水库的调节能力,促进风光资源的高效消纳,基于微观经济学生产产品时存在的边际产量递减规律,以水电站水库调节能力为可变要素,将风光资源消纳视为“固定要素”的充分发挥,建立了水风光联合发电效益最大模型,可求解得到促进风光资源经济消纳的水电站水库优化调度方案。算例分析结果表明:在入库流量、负荷需求以及水库运行状态等因素一定的条件下,模型可充分反映水电站水库参与风光出力调节时对风光资源的消纳和水风光联合发电效益的贡献,给出了不同情景下水电站水库参与风光出力调节的优化调度方案,对于在保障电力系统安全的前提下充分发挥水电站水库的调节能力和提升水风光联合发电效益具有一定的参考价值。

中国耗水结构综合分析及其驱动力研究

基于水足迹方法,量化了2010年和2019年中国除港澳台外31个省(自治区、直辖市)农业、工业、生活和生态部门的耗水量,以基尼系数、不平衡指数和水资源承载力为主要指标,评价了各省份耗水结构的空间均匀性、局部适配性和水资源脆弱性,并采用灰色关联法对各部门耗水特征进行了驱动力分析。结果表明:各部门耗水空间分布的均匀性差异显著,农业部门最优,2019年较2010年有所下降;生活和工业部门的水资源适配度最佳,2019年较2010年变化不大;北方地区较南方地区的水资源承载力更为脆弱,超载地区主要集中在黄淮海等地区,2019年较2010年更为严峻;作物播种面积、工业营业收入、城镇生活污水排放量和城镇环境基础建设投资分别是农业、工业、生活和生态部门耗水结构的最主要驱动因素。

计及负荷预测的风光柴储联供型微网系统的运行优化

微电网系统优化运行能够有效推进落实“双碳战略”,但微电网运行时未考虑负荷的动态变化及运行的多目标特性,限制了系统运行优化和可再生能源的消纳能力。针对该问题,建立由运行成本费用和环境治理费用构成的微电网总运行成本最低,以及可再生能源消纳最大化的多目标优化运行模型;针对电网负荷的动态变化,采用Holt-winters模型预测微电网系统负荷变化;最后用改进的多目标粒子群算法对微电网模型进行求解。为验证算法的可行性,以IEEE数据库中高比例新能源HRP-38标准系统和华东地区微电网为研究对象。算例表明,计及负荷预测下两类微电网系统中风电利用率分别提高了8.13%、5.23%,光伏利用率分别提高了8.59%、6.49%,系统总运行成本分别降低了8.29%、8.89%。因此,所提方法既能有效提高系统对可再生能源的消纳能力,又能降低系统的总运行成本,同时实现环境效益最大化,对微电网运行具有指导意义。

基于环境中移动运输代理的传感器网络建模

针对大型稀疏传感器网络中的数据获取,本文提出了一种利用环境中普遍存在的移动代理来连接稀疏传感器的网络体系结构和一种2-维网格随机游走分析模型;提出的传感器网络模型由3个抽象层构成,即由无线传感器构成的底层、由各种运输代理构成的中间层和由接入点/中央存储库构成的顶层。具体实现原理是位于中间层的移动运输代理从底层分布的无线传感器收集数据并缓冲数据,然后经过游走运输,最后将从底层的无线传感器收集的数据交付到顶层必要的接入点进行必要的存储和处理,从而实现整个传感器网络的数据获取;理论分析和仿真实验结果表明,提出的基于移动运输代理的传感器网络模型不仅具有较好的鲁棒性和可扩展性,而且相比于基站网络模型和Ad-hoc网络模型,在传感器功率消耗、数据成功率和基础设施投入成本方面有明显的优势。