Challenges for China to achieve carbon neutrality and carbon peak goals: Beijing case study

China has set a goal to achieve peak CO2 emissions before 2030 and carbon neutrality by 2060. To achieve the goals of carbon peak and carbon neutrality, China needs to address the challenge of the large and still growing CO2 emission base. This paper investigated the energy consumption and CO2 emission in Beijing from 2020–2035 based on the energy elasticity coefficient and contribution value of the sub-energy increment (CVSI) method. Beijing is one of the first cities in China to propose the "carbon peak” target as of 2020. From 2020 Beijing will strive to achieve the goal of carbon neutrality. The results show that in 2035 the CO2 emission in Beijing may drop to 50% of 2020. This decline would be affected by economic growth, energy efficiency and the proportion of renewable energy use. Beijing’s energy supply mainly comes from outside the region. Therefore, for Beijing, in addition to increasing the proportion of renewable energy sources outside the region, its own energy acceptance also needs to be strengthened, including strengthening energy storage construction, actively researching and promoting carbon capture and utilization of gas-fired units, which are effective ways to achieve carbon neutrality target.

Associations of Percent Energy Intake From Total, Animal and Plant Protein With Overweight/Obesity and Underweight Among Adults in Addis Ababa, Ethiopia

Objectives Obesity and diet-related noncommunicable diseases are increasing in Ethiopia—often in the same communities where undernutrition remains prevalent. Increasing proportion of energy intake from protein could be a potential strategy to address this double burden; however, this potential has not been examined in sub-Saharan Africa. The objective of this study is to investigate associations of types and food sources of protein with overweight/obesity and underweight in Ethiopia. Methods We conducted a cross-sectional dietary survey including 992 women and 632 men aged 18–49 years in Addis Ababa, Ethiopia. Linear regression models were used to assess associations between body mass index (BMI) and % energy intake from total, animal, and plant protein. Logistic regression models were used to examine associations of % energy intake from total, animal, and plant protein and specific food sources of protein with underweight and overweight/obesity. Results Nearly one third of the sample were overweight or obese. Only 2.5% of total energy intake was derived from animal protein. In multivariable-adjusted linear models in the full sample, BMI was not associated with % energy from total protein, plant protein or animal protein. Total protein and animal protein intake were both associated with lower odds of overweight/obesity (Odds Ratio [OR] per 1% energy increment of total protein 0.92; 95% CI: 0.86, 0.99; P = 0.02; OR per 1% energy increment of animal protein 0.89; 95% CI: 0.82, 0.96; P = 0.004) when substituted for carbohydrate and adjusted for sociodemographic covariates. In food-based analyses, a greater % energy from milk was related to lower odds of underweight but with wide confidence intervals (OR per 5% energy increment 0.54; 95% CI: 0.30, 1.00; P = 0.05). Conclusions Increasing the proportion of energy intake from total protein or animal protein in place of carbohydrate could be a strategy to address overweight and obesity in Ethiopia; longitudinal studies are needed to further examine this potential. Funding Sources United Kingdom Economic and Social Research Council (ESRC) and Department for International Development (DFID) Joint Fund for Poverty Alleviation Research.

Lesion outline and thermal field distribution of ablative in vitro experiments in myocardia: comparison of radiofrequency and laser ablation

Objectives To explore the lesion outline and thermal field distribution of radiofrequency ablation (RFA) and laser ablation (LA) in myocardial ablation in vitro. Materials and methods Twenty-four fresh porcine hearts were ablated with RFA or LA in vitro. The radiofrequency electrode or laser fiber and two parallel thermocouple probes were inserted into the myocardium under ultrasound guidance. The output power for RFA was 20 W/s and for LA was 5 W/s, and the total thermal energies were 1200 J, 2400 J, 3600 J, and 4800 J. The range of ablation lesions was measured, and temperature data were recorded simultaneously. Results All coagulation zones were ellipsoidal with clear boundaries. The center of LA was carbonized more obviously than that of RFA. With the accumulation of thermal energy and the extended time, all the ablation lesions induced by both RFA and LA were enlarged. By comparing the increase in thermal energy between the two groups, both the short-axis diameter and the volume change showed significant differences between the 1200 J and 3600 J groups and between the 2400 J and 4800 J groups (all P < 0.05). Both the short-axis diameter and the volume of the coagulation necrosis zone formed by LA were always larger than those of RFA at the same accumulated thermal energy. The temperatures of the two thermocouple probes increased with each energy increment. At the same accumulated energy, the temperature of LA was much higher than that of RFA at the same point. The initial temperature increase at 0.5 cm of LA was rapid. The temperature reached 43 °C and the accumulated energy reached 1200 J after approximately 4 min. After that the temperature increased at a slower rate to 70 C. For the RFA at the point of 0.5 cm, the initial temperature increased rapidly to 30 °C with the same accumulated energy of 1200 J after only 1 min. In the range of 4800 J of accumulated thermal energy, only the temperature of LA at the point of 0.5 cm exceeded 60 °C when the energy reached approximately 3000 J. Conclusions Both RFA and LA were shown to be reliable methods for myocardial ablation. The lesion outline and thermal field distribution of RFA and LA should be considered when performing thermal ablation in the intramyocardial septum during hypertrophic obstructive cardiomyopathy.

Renewable Energy Curtailment: Prediction Using a Logic-Based Forecasting Method and Mitigation Measures in Kyushu, Japan

High variable renewable energy (VRE) penetration led to the first-ever VRE curtailment in Japan, occurring in Kyushu in October 2018. Since then, there has been an average of 3% solar curtailment, with a peak of 13.7% in April 2019, resulting in approximately ¥9.6 billion of wasted energy. The VRE curtailment is expected to worsen as VRE penetration continues to increase along with nuclear energy increment in line with Japan’s 2030 energy goals. To prevent this curtailment and increase energy stability, a novel, logic-based forecasting method using hourly supply/demand data was developed. Initially, inaccurate results were returned; however, after several rounds of calibration that adjusted the quartile value of the max/min operating windows, the overall accuracy of this method was increased to 97% of real curtailment. This calibrated model was then used to test several curtailment mitigation scenarios. Some scenarios increased curtailment, while the two most successful scenarios, which reduced the installed nuclear capacity either seasonally or totally, limited curtailment by 95% and 97%, respectively. Another scenario with increased grid interconnection between regions reduced curtailment by 79%. Moreover, it would provide other benefits by unifying the national grid thereby increasing disaster resistance, reducing curtailment, improving grid flexibility and allowing for higher VRE penetrations. Currently, the situation is worsening, and some actions are required to reduce the curtailment and to achieve its 2030 energy goals in Japan. The mitigation measures studied by the logic method could be recommended to be referred to.

Theoretical Model of the Axial Residual Velocity of PELE Projectiles Penetrating Thin Metal Targets

With the increase of battlefield target diversity and protection mobility, the disadvantages of traditional armor piercing warheads have gradually become prominent. The conception of the PELE (penetration with enhanced lateral efficiency) projectile was thus proposed. The axial residual velocity of the projectile is a very important indicator of a PELE projectile, which mainly reflects the penetration ability of the PELE projectile. The PELE projectile is a symmetrical structure, so the collision problem can be simplified to plane collision. Furthermore, the two-dimensional plane is axisymmetric, and so it can be further simplified to one-dimensional collision. Based on simplification and assumptions, the mechanism of a PELE projectile penetrating a thin metal target plate was studied using the shock wave theory, and a theoretical model of axial residual velocity has been established in this article. The energy loss during the penetration process was divided into the following parts: the kinetic energy increment of the target plug in the impact region, the internal energy increment of the outer casing and inner core, and the shear energy dissipation of the projectile against the target plate. In addition, the specific methods of determining the energy loss of each part are given in detail. According to the conservation of energy, the approximate calculation formulae of the axial residual velocity of a PELE projectile have been deduced. Finally, the theoretical results were compared with the experimental results under different working conditions, and the results were in good agreement. Therefore, the theoretical model has application value and guiding significance in the field of engineering.

Main Lemma Implies the Main Theorem

This chapter shows that the Main Lemma implies the main theorem. It proves Theorem (10.1) by inductively applying the Main Lemma in order to construct a sequence of solutions of the Euler-Reynolds system. At each stage of the induction, an energy function is chosen along with a parameter whose choice determines the growth of the frequency parameter and the decay of the energy level. A base case lemma is then established, after which the proof of the Main Theorem (10.1) is presented so that the Main Lemma implies the Main Theorem. The Main Lemma is employed to approximately prescribe the energy increment of the correction. The solution obtained at the end of the process is nontrivial.

Constructing Continuous Solutions

This chapter demonstrates how the preceding construction, combined with a few estimates from Part V, can be used to prove the Main Lemma for continuous solutions. The first step is to mollify the velocity, followed by mollification of the stress. The lifespan is then chosen, preferring a small parameter to ensure that the first term in the parametrix for the High–High term is controlled. The chapter proceeds by discussing the bounds for the new stress and solving the divergence equation, along with the bounds for the corrections and finally, control of the energy increment. The equation for the energy increment includes a smooth vector field and involves bounding the error term.

Existence, numerical convergence and evolutionary relaxation for a rate-independent phase-transformation model

We revisit the model for a two-well phase transformation in a linearly elastic body that was introduced and studied in Mielke et al. (2002 Arch. Ration. Mech. Anal. 162 , 137–177). This energetic rate-independent system is posed in terms of the elastic displacement and an internal variable that gives the phase portion of the second phase. We use a new approach based on mutual recovery sequences , which are adjusted to a suitable energy increment plus the associated dissipated energy and, thus, enable us to pass to the limit in the construction of energetic solutions. We give three distinct constructions of mutual recovery sequences which allow us (i) to generalize the existence result in Mielke et al. (2002), (ii) to establish the convergence of suitable numerical approximations via space–time discretization and (iii) to perform the evolutionary relaxation from the pure-state model to the relaxed-mixture model. All these results rely on weak converge and involve the H-measure as an essential tool.