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The article presents the results on the study of key economically beneficial traits of pedigree French Holstein cows in the herd of Society of limited liability "Holstein." It was found that the milk yield of cows in the first lactation averaged 8119 kg of milk, and in the second lactation, it was 8226 kg of milk, which is by 107 kg more than in the first lactation. Comparative analysis of the milk productivity of locally generated cows and their mothers revealed that the daughters' yields (cows of local generation) during the first lactation period of 305 days exceeded the mothers' yields by 1367 kg of milk. In the second lactation, the average yield of locally generated cows was 8505 kg of milk, which is by1253 kg more than the average in the first lactation. A positive correlation was established for milk yield during the 305-day lactation period between the first and second lactations (+0.201). The heritability coefficient for lactation yield was determined to be (h2 = 0.402). [ABSTRACT FROM AUTHOR]

Magnetosonic (MS) waves are dominant plasma waves causing severe Martian ionospheric erosion. They are generally considered to originate upstream of Martian bow shock with frequencies near the upstream proton gyrofrequency. However, whether MS waves can be locally excited lacks theoretical analysis. Here we present an event of MS waves with frequencies above and closely related to the local proton gyrofrequency in the Martian ionosphere. Concurrently, ring beam hot proton distributions are observed due to the penetration of magnetosheath protons. By employing the observed plasma and magnetic field data, the calculated linear growth rates for MS waves agree well with the observed wave power spectra, demonstrating that they can be locally excited by unstable ring beam hot protons at Mars. Our results could be of great help in understanding the excitation of MS waves in a heavy ion‐rich environment around unmagnetized planets. Plain Language Summary: Magnetosonic (MS) wave is one of the most important plasma waves contributing to the Martian atmospheric loss. They are generally considered to originate upstream of the Martian bow shock. Recent observations at Mars have shown that some MS waves with frequencies near the local proton gyrofrequency were accompanied by ring/shell‐like hot proton distributions. However, whether these waves can be locally excited by such protons lacks the support of the theoretical analysis. In this letter, on the basis of linear instability analysis, we show that MS waves with frequencies well above the local proton gyrofrequency can be locally excited by unstable ring beam hot protons in the Martian ionosphere. These results advance our knowledge of the MS wave excitation in a heavy ion‐rich environment around planets without an intrinsic magnetic field. Key Points: Magnetosonic waves above the local proton gyrofrequency are observed in the Martian ionosphereRing beam hot proton distribution associated with magnetosonic waves is formed by the penetration of solar wind protons simultaneouslyMagnetosonic waves are locally generated by the ring beam hot protons [ABSTRACT FROM AUTHOR]

The increasing demand of energy in the traditional grids is getting more complex, less feasible, harmful, uneconomical and high in power losses. This paper presents an efficient energy management approach to mitigate such issues with smart micro grid (SMG) and aims at a solution that is both cost effective and eco-friendly, within energy market paradigm. Goals are achieved with the help of Home Energy Management Controller (HEMC), Energy Market Management Controller (EMMC) and Control Agent (CA). The individual load is managed in the presence of local generation, storage system, user comfort, DGs and Utility within energy market paradigm. Two level energy management approach is proposed to achieve concerned goals. First is to manage load and schedule storage with respect to individual local generation and market pricing. Second is to manage energy market with the help of four different types of priorities and control agent input. The problem is solved with a variant of meta-heuristic method, Multi Objective Grey Wolf Optimization (MOGWO), which gives more comprehensive solution by comparing with Particle Swarm Optimization (PSO). The proposed methodology is implemented on a SMG based-community test system. Homes within that community have different economic conditions and personal priorities. Simulation results demonstrates achievement of aimed goals in presented work.

Abstract Ensuring access to reliable and sustainable power supply is becoming more and more challenging due to a combination of factors such as more frequent power grid outages caused by extreme weather events, the large-scale introduction of renewable energy resources that increases the complexity of the power system, but also aging infrastructure, supply and demand imbalance and power theft in some areas. Combined, all these factors can cause outages and together they can make electricity supply unreliable. The implications of this are many, ranging from minor inconveniences to major failures of critical infrastructures. A potential solution to ensure power supply during outages is to use local generation in the form of renewable resources to supply energy. This paper proposes a community-based mechanism that demonstrates that when community members can determine for themselves how excess energy generation is distributed, the power supply of specific members can be ensured. Self-determination is achieved by prioritizing and differentiating between community members as well as automatically and continuously redistributing energy, thereby adapting to sudden changes in supply and demand. Simulation results show that the proposed mechanism can be used to empower local communities to decide for themselves how local resources are distributed during events such as outages, ensuring prolonged power supply for differentiated members of affected communities. Harnessing the potential of renewable resources and smart technologies for intelligent coordination through empowerment of consumers to become pro-active participants is a promising solution for the future power systems.

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This study is an evaluation of the use and supply of compressed air, which is one of the most expensive energy sources in manufacturing, at Ford Motor Company’s Livonia (Mich.) Transmission Plant. The aim of the study is to make recommendations to improve environmental and economic efficiency in future facilities. This paper presents a quantitative analysis of three compressed air supply patterns—plant air, point of use (POU), and local generation—as alternatives for future compressed air usage. Environmental Value systems(EnVS) tools are employed to analyze the economic and environmental performance of the three alternative supply patterns by using cost of ownership and environmental impact matrices. The results favor local generation over the other two alternatives in terms of economic and environmental considerations.

Hydrogen therapy has attracted increasing attention in clinical/preclinical studies as an emerging and promising therapy technique owing to its selective antioxidative properties. Microfactories for intracellular local hydrogen production are an efficient intracellular hydrogen delivery system with targeted, controlled, and sustained release. In this Minireview, recently developed materials, technologies, and strategies for locally generated hydrogen therapy are summarized. Different driving forces including ultrasound, light, and chemical reactions are critical to the in situ production of hydrogen for the hydrogen therapy process. The therapeutic mechanisms and effectiveness of this locally generated hydrogen were evaluated based on the type of disease models, with an emphasis on tissue inflammation and cancer. Furthermore, the challenges and opportunities of constructing these microfactories for locally generated hydrogen therapy are discussed. [ABSTRACT FROM AUTHOR]

Ground-level ozone is a secondary pollutant produced by photochemical reactions and it adversely affects plant and human health. Taiyuan City, a typical city on the loess plateau, is suffering from severe ozone pollution. We utilized the data from eight national environmental monitoring sites of Taiyuan, including concentrations of O3 and nitric oxide, and meteorological factors, such as air temperature and wind, to study the pollution characteristics and sources of ozone (O3) in Taiyuan in 2018. Results show that during 2018, the maximum value and 90th percentile of the maximum 8-h running average of O3 concentration were 257 μg/m3 and 192 μg/m3, respectively. There were 72 days where the O3 concentration exceeded the standard in 2018, which were mainly during April to August. The O3 concentration increased from March, reached a high level in April through August, and decreased significantly from September. The O3 concentrations displayed a typical “single peak” diurnal variation, which was high during the day with peak at around 13:00–15:00 and low at night. From April to August, the O3 concentrations at Jinyuan was the highest, followed by Xiaodian and Taoyuan, and the O3 concentrations at Shanglan and Nanzhai were the lowest. When the O3 concentration exceeded the standard value, Jinyuan contributed the most to the O3 pollution of Taiyuan, followed by Taoyuan and Xiaodian. High temperature and pressure, south and southwest winds can lead to an increase in O3 concentration. The O3 pollution in the Taiyuan urban area is caused by local generation, and the transportation of polluted air masses containing oxides of nitrogen (NOx) and volatile organic compounds (VOCs) emitted by industries, such as the coking and steel plants in counties of Jinzhong City in southern Taiyuan, and Qingxu County, and some counties in Lyuliang City to the southwest. In addition, the mountain winds and low nitric oxide concentration are the main reasons for the increase of O3 concentration, often observed in Shanglan at night.

The generation of a high‐frequency plasmaspheric hiss (HFPH) wave observed by Van Allen Probes is studied in this letter for the first time. The wave has a moderate power spectral density (∼10−6 nT2/Hz), with a frequency range extended from 2 to 10 kHz. The correlated observations of waves and particles indicate that HFPH is associated with the enhancement of electron flux during the substorm on 6 January 2014. Calculations of the wave linear growth rate driven by the fitted electron phase space density show that the electron distribution after the substorm onset is efficient for the HFPH generation. The energy of the contributing electrons is about 1–2 keV, which is consistent with the observation. These results support that the observed HFPH is likely to be generated locally inside the plasmasphere due to the instability of injected kiloelectron volt electrons. Plain Language Summary: Plasmaspheric hiss is an electromagnetic wave inside the plasmasphere, efficient for the precipitation of the radiation belt electrons into the atmosphere. Its typical frequency peaks below ∼1 kHz and rarely exceeds 2 kHz. However, a high‐frequency plasmaspheric hiss (HFPH) wave with a frequency extended up to 10 kHz was observed by Van Allen Probes during a substorm on 6 January 2014, and the generation mechanism of the waves is studied in this letter for the first time. We find that HFPH is associated with the instability of the local energetic electrons driven by the substorm injection. Further theoretical analysis shows that the injected electrons with energy level around 1–2 keV provide the main free energy for the HFPH generation, consistent with the observation. This quantitative study gives a reasonable explanation for the local generation of HFPH by kiloelectron volt electrons injected during substorm. These new finding will allow further developments in the modeling of plasmaspheric hiss waves and their effect on the radiation belt electrons. Key Points: The generation of plasmaspheric hiss with a high frequency up to 10 kHz is studied for the first timeThe high‐frequency hiss generated locally inside the plasmasphere is related to a substorm injectionSubstorm injected ∼1‐2 keV electrons inside the plasmasphere are responsible for the local generation of high‐frequency hiss [ABSTRACT FROM AUTHOR]

Cascaded on-load tap changers (OLTCs) are widely used for coarse control of voltages in largely interconnected electric power systems. There could be interactions between load dynamics and OLTC control under certain system operating conditions which may lead to the OLTC limit cycle phenomena, thereby resulting into long-term voltage oscillations in the system. In recent years, renewable and nonrenewable local generation (LG) units have been getting interconnected in modern power systems. The existence of OLTC limit cycles in the presence of LG has not been addressed in the literature in greater details. In this paper, the OLTC limit cycle phenomenon, which can occur due to interactions among load dynamics, OLTC controls, and LG operation in electricity networks, has been investigated. Also, a novel strategy is explored for mitigating the power system oscillations introduced by OLTC limit cycles, especially for a network embedded with LG. The proposed mitigation strategy including detailed investigations and analyses has been verified for a two-bus test system and successfully tested on a multibus system using MATLAB. [ABSTRACT FROM AUTHOR]

In this paper we aim to clarify the generation of Internal Solitary Waves (ISWs) at work to the east of the Mascarene Plateau (Indian Ocean) using Synthetic Aperture Radar (SAR) imagery and MITgcm fully nonlinear and nonhydrostatic simulations. Realistic representations of stratification and bathymetry are used with asymmetric tidal forcing (including the steady South Equatorial Current which is assumed barotropic in the model) along a 2D transect aligned with the propagation direction of the wave signatures identified in the SAR. The combined flow (i.e. steady and tidal currents) is subcritical with respect to first-mode Internal Waves (IWs), but supercritical with respect to higher wave modes. Different types of nonlinear wave trains with distinct origins (i.e. tidal phase and location) have been identified with the combined aid of model and SAR: (1) large-scale primary mode-1 ISWs evolve from the disintegration of a multimodal baroclinic structure that appears on the upstream side of the sill; (2) mode-2 ISW-like waves that evolve from this same baroclinic structure and are arrested over the sill before being released upstream at the change of flow condition; (3) a large mode-2 lee wave is generated downstream of the sill (i.e. on the west side), which is trapped there during maximum westward tidal flow and released upstream when the tide relaxes; and (4) mode-2 ISW-like waves whose length-scales are O (20 km) appear some 50 km upstream of the sill, after an Internal Tide (IT) beam scatters into the pycnocline, itself originating from critical topography on the leeward (i.e. westward) side of the sill. The underwater sill being investigated is in the mixed-tidal-lee wave regime, where the internal tide release mechanism, lee wave generation and IT beams can coexist. The large-scale mode-2 ISW-like waves that form far upstream from the sill are long-lived features and can be identified in the SAR due to associated short-scale mode-1 ISWs which propagate with the same phase speed, i.e. in resonance. This coupling is also seen in the model, and here it is argued that the formation of those mode-2 ISW-like waves appears to originate from the IT beam after it reflects from the sea surface and interacts with the pycnocline, a generation mechanism referred in the literature as “local generation of ISWs”. This IW generation process may be easily overlooked and could be at work in many more regions of the world than previously thought. [ABSTRACT FROM AUTHOR]

In this paper, we consider a job scheduling problem with random local generation, in which some jobs must be scheduled ahead of time while the others can be scheduled in a real-time fashion. To capture the randomness of the locally distributed generation, we develop a two-stage robust optimization model by considering an uncertainty set without probability information. Given that the problem is challenging, a nested column-and-constraint generation algorithm is implemented to find an optimal solution. Some computational study, along with management insights, is presented to show the effectiveness of the proposed model in dealing with the worst case situations. [ABSTRACT FROM PUBLISHER]

The term local generator as used in this paper is intended to describe a generator supply dedicated to a specific facility which would have a more limited and specific capacity and loading than a broader and higher capacity utility supply. These systems, particularly when there is a large nonlinear component, require additional coordination and design considerations as a result. Generator suppliers obviously understand their equipment in great detail and have well-defined application guidelines for the more typical linear loads which they are expecting to supply. Adjustable-speed drives (ASDs) and other nonlinear loads bring additional factors into play such as harmonics, possible requirement for harmonic filters, and the specifics of their topology design such as the inherent capacitance involved in all drive designs. The intent of this paper is to address the necessary application considerations when applying nonlinear loads on local generation starting at the basics of sizing and progressing through topics such as alternator sizing, voltage and speed regulation, etc. Specific focus will be with respect to an application issue which arose for a recent offshore application involving a high component of nonlinear ASD loading on their offshore distribution system per the author's experience. [ABSTRACT FROM AUTHOR]

In recent years, the distribution of local and renewable generation plants has introduced significant challenges in the management of electrical energy. In order to increase the usage of renewable energy, the prosumers, i.e., the residential users that can act both as producers and consumers, can benefit from joining together and forming energy communities. The deployment of an energy community is based both on technological advancements and on a deep understanding of human decision-making, which in turn requires knowledge about the factors that influence the behavior of residential users. This new scenario calls for great research investigations aimed to improve the management of energy exchanges inside energy communities. An important role in this context is played by the Internet of Things (IoT) technology, as smart IoT objects are used both as a source of real-time information regarding the energy production and the users' requirements, and as actuators that can help to regulate the distribution and use of energy. In this paper, an IoT-aware optimization model for the energy management in energy communities is presented. The main novelty consists in modeling the entire energy community as a whole, rather than each prosumer separately, with the goal of optimizing the energy sharing and balance at the community level. Experimental results, performed in an university campus, show the advantages of the approach and its capability of reducing the energy costs and increasing the community's energy autonomy. [ABSTRACT FROM AUTHOR]

Ground-level ozone is a secondary pollutant produced by photochemical reactions and it adversely affects plant and human health. Taiyuan City, a typical city on the loess plateau, is suffering from severe ozone pollution. We utilized the data from eight national environmental monitoring sites of Taiyuan, including concentrations of O3 and nitric oxide, and meteorological factors, such as air temperature and wind, to study the pollution characteristics and sources of ozone (O3) in Taiyuan in 2018. Results show that during 2018, the maximum value and 90th percentile of the maximum 8-h running average of O3 concentration were 257 μg/m3 and 192 μg/m3, respectively. There were 72 days where the O3 concentration exceeded the standard in 2018, which were mainly during April to August. The O3 concentration increased from March, reached a high level in April through August, and decreased significantly from September. The O3 concentrations displayed a typical "single peak" diurnal variation, which was high during the day with peak at around 13:00–15:00 and low at night. From April to August, the O3 concentrations at Jinyuan was the highest, followed by Xiaodian and Taoyuan, and the O3 concentrations at Shanglan and Nanzhai were the lowest. When the O3 concentration exceeded the standard value, Jinyuan contributed the most to the O3 pollution of Taiyuan, followed by Taoyuan and Xiaodian. High temperature and pressure, south and southwest winds can lead to an increase in O3 concentration. The O3 pollution in the Taiyuan urban area is caused by local generation, and the transportation of polluted air masses containing oxides of nitrogen (NOx) and volatile organic compounds (VOCs) emitted by industries, such as the coking and steel plants in counties of Jinzhong City in southern Taiyuan, and Qingxu County, and some counties in Lyuliang City to the southwest. In addition, the mountain winds and low nitric oxide concentration are the main reasons for the increase of O3 concentration, often observed in Shanglan at night. [ABSTRACT FROM AUTHOR]

Ensuring access to reliable and sustainable power supply is becoming more and more challenging due to a combination of factors such as more frequent power grid outages caused by extreme weather events, the large-scale introduction of renewable energy resources that increases the complexity of the power system, but also aging infrastructure, supply and demand imbalance and power theft in some areas. Combined, all these factors can cause outages and together they can make electricity supply unreliable. The implications of this are many, ranging from minor inconveniences to major failures of critical infrastructures. A potential solution to ensure power supply during outages is to use local generation in the form of renewable resources to supply energy. This paper proposes a community-based mechanism that demonstrates that when community members can determine for themselves how excess energy generation is distributed, the power supply of specific members can be ensured. Self-determination is achieved by prioritizing and differentiating between community members as well as automatically and continuously redistributing energy, thereby adapting to sudden changes in supply and demand. Simulation results show that the proposed mechanism can be used to empower local communities to decide for themselves how local resources are distributed during events such as outages, ensuring prolonged power supply for differentiated members of affected communities. Harnessing the potential of renewable resources and smart technologies for intelligent coordination through empowerment of consumers to become pro-active participants is a promising solution for the future power systems. [ABSTRACT FROM AUTHOR]