Gravity System Research Articles

OneMars: Requirements for Artificial Gravity in a Spacecraft for Transportation of a Crew to Mars

This paper used the processes of simultaneous and systems engineering to develop a solution that addresses both the main concerns of a manned mission to Mars and the Artificial Gravity System (AGS) requirements that shall be used during the concept phase of a spacecraft to be utilized to transport a crew to Mars. The study shows different tools of the systems engineering process. Steps taken in the paper include: (a) determining the main stakeholders, objectives and measures of effectiveness, analysis of the operation scenario, capabilities and constraints, concept of operations; (b) outlining the lifecycle of the project and determining main reviews and the product breakdown structure; (c) analyzing stakeholder for the spacecraft, including concerns and requirements; (d) breaking down stakeholder requirements to non-functional and functional requirements; (e) analyzing the system’s main functions by reviewing the context, circumstances, operation modes, list of events, essential functions, hazards and risks; (f) architecting the spacecraft through: breakdown of subsystems, morphological diagram, architecture flow and interconnect diagrams, analysis of artificial gravity options and requirements specification for the artificial gravity subsystem.

Scalar-tensor theories within Asymptotic Safety

Asymptotic Safety provides an elegant mechanism for obtaining a consistent high-energy completion of gravity and gravity-matter systems. Following the initial idea by Steven Weinberg, the construction builds on an interacting fixed point of the theories renormalization group (RG) flow. In this work we use the Wetterich equation for the effective average action to investigate the RG flow of gravity supplemented by a real scalar field. We give a non-perturbative proof that the subspace of interactions respecting the global shift-symmetry of the scalar kinetic term is closed under RG transformations. Subsequently, we compute the beta functions in an approximation comprising the Einstein-Hilbert action supplemented by the shift-symmetric quartic scalar self-interaction and the two lowest order shift-symmetric interactions coupling scalar-bilinears to the spacetime curvature. The computation utilizes the background field method with an arbitrary background, demonstrating that the results are manifestly background independent. Our beta functions exhibit an interacting fixed point suitable for Asymptotic Safety, where all matter interactions are non-vanishing. The presence of this fixed point is rooted in the interplay of the matter couplings which our work tracks for the first time. The relation of our findings with previous results in the literature is discussed in detail and we conclude with a brief outlook on potential phenomenological applications.

Carbon Impact and Cost of Mass Timber Beam–Column Gravity Systems

The need to lower the embodied carbon impact of the built environment and sequester carbon over the life of buildings has spurred the growth of mass timber building construction, leading to the introduction of new building types (Types IV-A, B, and C) in the 2021 International Building Code (IBC). The achievement of sustainability goals has been hindered by the perceived first cost assessment of mass timber systems. Optimizing cost is an urgent prerequisite to embodied carbon reduction. Due to a high level of prefabrication and reduction in field labor, the mass timber material volume constitutes a larger portion of total project cost when compared to buildings with traditional materials. In this study, the dollar cost, carbon emitted, and carbon sequestered of mass timber beam–column gravity system solutions with different design configurations was studied. Design parameters studied in this sensitivity analysis included viable building types, column grid dimension, and building height. A scenario study was conducted to estimate the economic viability of tall wood buildings with respect to land costs. It is concluded that, while Type III building designations are the most economical for lower building heights, the newly introduced Type IV subcategories remain competitive for taller structures while providing a potentially significant embodied carbon benefit.

A two-fluid arrangement with bounded van der Waals body forces. Part 1. The Young-Laplace equilibria. Differences from comparable gravity systems

A two-fluid arrangement with bounded van der Waals body forces. Part 1. The Young-Laplace equilibria. Differences from comparable gravity systems

Analytic topological hairy dyonic black holes and thermodynamics

We present and discuss a new family of topological hairy dyonic black hole solutions in asymptotically anti--de Sitter space. The coupled Einstein-Maxwell-scalar gravity system, that carries both the electric and magnetic charges is solved, and exact hairy dyonic black hole solutions are obtained analytically. The scalar field profiles that give rise to such black hole solutions are regular everywhere. The hairy solutions are obtained for planar, spherical, and hyperbolic horizon topologies. In addition, analytic expressions of regularized action, stress tensor, conserved charges, and free energies are obtained. We further comment on different prescriptions for computing the black hole mass with hairy backgrounds. We analyze the thermodynamics of these hairy dyonic black holes in canonical and grand canonical ensembles, and we find that both electric and magnetic charges have a constructive effect on the stability of the hairy solution. For the case of planar and hyperbolic horizons, we find thermodynamically stable hairy black holes that are favored at low temperatures compared to the nonhairy counterparts. We further find that, for a spherical hairy dyonic black hole, the thermodynamic phase diagram resembles to that of a Van der Waals fluid not only in canonical but also in the grand canonical ensemble.

Planning of clean water distribution network Kamosope Village, Pasir Putih District, Muna Regency

The availability of clean water is essential for human life because clean water is the primary human need. It is imperative to plan a clean water supply system that is appropriately managed. Kamosope Village does not yet have a reasonable and adequate clean water network system, so it is necessary to plan a sound clean water supply network system to serve the community. The source of water to be used is river water. The designed clean water network system collects water from the river then the water is distributed to the population through a gravity system. The clean water network system is planned to meet the needs of clean water until 2029. The need for clean water is calculated based on the projected population using the Least Square method. From the calculation results, the need for clean water in Kamosope Village in 2029, with 723 people, reaches 1.753 liters/second. Kamosope river discharge based on field measurements using the buoy method is 0.535 m³/second or 107 liters/second. Distribution pipe diameters are the inch, 1 inch, 1½ inch, and 2 inches. EPANET 2.0 software is used to design the clean water network system.

Water Purification System Based on Rapid Gravity System and City Supply (Raw Water from River Hooghly)

Abstract: The present study is aimed to develop an understanding on the principles and working of a Rapid Gravity Water Treatment Plant with River Hooghly as its source. The following project gives us an insight to the relative workings of the various parts of the Water Treatment Plant from source to distribution. This also includes detailed design of each of the components of the system.

Cost-Effectiveness of Mass Timber Beam–Column Gravity Systems

Abstract The cost of mass timber buildings is a major point of interest to building developers and architects because it often dictates the fate of proposed mass timber projects. Cost estimation fo...

Born–Oppenheimer meets Wigner–Weyl in quantum gravity

Starting from a Born–Oppenheimer decomposition of the Wheeler-DeWitt equation for the quantum cosmology of the matter–gravity system, we have performed a Wigner–Weyl transformation and obtained equations involving a Wigner function for the scale factor and its conjugate momentum. This has allowed us to study in more detail than previously the approach to the classical limit of gravitation and the way time emerges in such a limit. To lowest order we reproduce the Friedmann equation and the previously obtained equation for the evolution of matter. We also obtain expressions for higher order corrections to the semi-classical limit.

Local empowerment and irrigation devolution in Ethiopia

ABSTRACT This paper investigates the effect of devolved irrigation water management systems and complementary irrigation technologies on collective empowerment in Ethiopia. We find that households’ monetary, in-kind and labour contributions for irrigation water provision and appropriation are more common in farmer-managed gravity irrigation schemes compared with farmer-managed pump systems and jointly managed schemes. The most frequent conflict occurrence was observed in jointly managed gravity irrigation systems, followed by farmer-managed gravity systems. Our results indicate that irrigation users’ degree of participation, decision-making capacity and strength of local governance are also affected by several household, plot, village, scheme and climatic factors.

The Concept of Optimal Compaction of the Charge in the Gravitation System Using the Grains Triangle for Cokemaking Process

Two isomorphic sets of grains, small and large, were analysed—without specifying their dimensions—under the acronym CMC (Curve of Maximum Compression) and taking into account the effects of segregation CMCS. The proposal is particularly valuable for optimal blend preparation in the gravity system in cokemaking. The main advantage of this work is the proposal of using the grains triangle, which limits the values calculated by the relations: bulk density-share of coarse/fine grains, for different levels of moisture content. Each system of changing shares of coarse grains is characterised by a constant C, but there is no need to determine it. Compliance of the calculated value with the experimentally determined value means that the given arbitrary grain set has reached its maximum density called the “locus”. The grains triangle practically covers the vast majority of laboratory and industrial test results, and geometrically or computationally indicates the ability of a given particle size distribution to reach maximum bulk density. This paper presents analysis of the results of tests on crushing, coal briquettes, and grinding coal blend in selected mechanical systems. Results of tests on coke quality (CRI, CSR) in connection with the grain size triangle are discussed.

Gravity and gravity-pump sewage systems including energy embodied in each system – case studies

ABSTRACT In this article, the entire energy embodied in a sewage system has been estimated. The concepts of LCC, LCA and EE have been taken into consideration. The estimation of this energy is calculated from the moment of extracting the raw materials, through its transportation, to the making of a final product. The choice of materials and production technology is an important aspect here. This article considers the construction procedure of a gravity and gravity-pump sewage system, including estimating the amount of energy. In order to calculate the energy embodied in a sewage system, not only the cost of materials and transportation need to be taken into account but also the energy needed for laying a pipeline in the ground, system operation and the lifetime of the system’s components. The article aims to estimate the entire energy embodied in both aforementioned sewage system type. The most rational solution has been chosen.

Degradation effect of ultraviolet-induced advanced oxidation of chlorine, chlorine dioxide, and hydrogen peroxide and its impact on coagulation of extracellular organic matter produced by Microcystis aeruginosa

Implementation of an ultraviolet (UV)-induced advanced oxidation process (AOP) before coagulation was found to enhance the removal of algae cells. However, the effect of UV-induced AOPs on extracellular cellular organic matter (EOM) and on its coagulation and removal was neglected. This study investigated the impact of UV-induced AOPs (UV/Cl2, UV/ClO2, and UV/H2O2) on EOM from Microcystis aeruginosa, and its coagulation and removal by a conventional gravity system (CGS), dissolved air flotation, and a low-energy flash-pressurized flotation (FPF) process. The changes in EOM characteristics before and after the UV-induced AOPs were based on UV absorbance (UV254) and liquid chromatography with organic carbon detection analysis. The reduction in UV254 increased with an increasing dose of oxidant and UV irradiation. The reduction in UV254 for UV/Cl2, UV/ClO2 and UV/H2O2 was 59.5%, 26.5%, and 17.5% respectively, for 0.71 mM equimolar concentration of oxidant and 1920 mJ/cm2 UV irradiation, as evident from a pseudo-first order kinetics study. Similarly, degradation of the high molecular weight to low molecular weight (LMW) fraction was pronounced for UV/Cl2. The coagulation efficiency decreased after UV-induced AOP in the following order: UV/H2O2 > UV/ClO2 > UV/Cl2. By contrast, the low-energy FPF process showed a higher removal of LMW fractions than CGS. Thus, low-energy FPF could be an alternative technology for the UV-induced AOP treatment system.

Entanglement Entropies of Equilibrated Pure States in Quantum Many-Body Systems and Gravity

We develop a universal approximation for the Renyi entropies of a pure state at late times in a non-integrable many-body system, which macroscopically resembles an equilibrium density matrix. The resulting expressions are fully determined by properties of the associated equilibrium density matrix, and are hence independent of the details of the initial state, while also being manifestly consistent with unitary time-evolution. For equilibrated pure states in gravity systems, such as those involving black holes, this approximation gives a prescription for calculating entanglement entropies using Euclidean path integrals which is consistent with unitarity and hence can be used to address the information loss paradox of Hawking. Applied to recent models of evaporating black holes and eternal black holes coupled to baths, it provides a derivation of replica wormholes, and elucidates their mathematical and physical origins. In particular, it shows that replica wormholes can arise in a system with a fixed Hamiltonian, without the need for ensemble averages.

Study of Adiabatic Flame Temperature of a Jet Combustor using a Non-Circular Inlet

An experimental investigation on heat transfer at various zones of the combustion chamber has been carried out using a non-circular inlet at the flame tube. With an aim to improve the turbulent level in flow, the non-circular section used here is an elliptical one. In addition to this, two rectangular tabs are placed at major axis of the ellipse to achieve an efficient mixing of fuel and air. Fuel used for combustion is kerosene while LPG gas is used for pre ignition. Fuel is fed to the chamber by gravity system and it has been atomized by two fish tank pumps. Ignition of the fuel is done by spark plug with a separate setup. The setup comprises of growler and CDI coil which are powered electrically. During the experiment, combustion has been initiated by allowing the air from blower to the chamber. The fuel is sprayed into the flame tube through fuel injector placed at a specified distance. After the proper mixing of fuel and air, the mixture is ignited by spark plug setup. Initially LPG gas was used for preheating followed by kerosene for combustion. Fuel tank has been calibrated for mass flow rate. The experiment has been carried out for different intervals of time and the heat transferred from the flame tube wall and chamber wall is been measured using an infrared gun (ray gun) by pointing laser on the wall. The temperatures at different zones have been measured. It is seen that the overall heat transfer at secondary zone is minimum when compared with other zones for the same period of time. This indicates that if the fuel injector is placed before the secondary zone, then a maximum flame temperature can be obtained. This leads to an improvement in efficiency of the combustion chamber.

Determinants of Ethiopian Coffee Exports to Its Major Trade Partners: A Dynamic Gravity Model Approach

The aim of this article is to examine export determinants of Ethiopian coffee to 31 trade partner countries using a dynamic gravity model and system generalised moment method of estimation (GMM) for the period 1998–2016. Descriptive results showed that Ethiopia was exporting only 39% of its total coffee production, and 53.5% and 34.13% of Ethiopian coffee exports were directed to European and Asian countries, respectively, over the period 1998–2016. Regression results revealed that trade openness, population size of Ethiopia, foreign direct investment and institutional quality index of Ethiopia are positively and significantly affecting volume of Ethiopian coffee export. But population of partner countries, weighted distance, lagged export volume and real exchange rate are negatively and significantly influencing export volume of Ethiopian coffee. Hence, Ethiopia needs to diversify its export destinations and export items a way from primary agricultural exports to secondary industrial exports in order to secure dependable source of foreign currency. Also, controlling corruption, increasing government effectiveness, ensuring political stability promotion of foreign direct investment and encouraging trade liberalisation would help to boost the volume of Ethiopian coffee export. JEL Codes: F12, F13, F14

Effect of hole diameter and basin size on the vortex gravity system

The vortex gravity system consists of a tube basin, a canal (worksection) and a water tank. Water is pumped into the upper tanker and flowed into the canal by opening the valve which then hits the tube basin and creates a whirlpool. The water that hits the tube and enters the outlet hole goes down to the lower tank and is circulated back to the upper tank. The outlet hole in the tube has 4 sizes and the tube size has 3 sizes. This study is based on experimental tests to determine the flow performance of the outlet diameter of the tube against the formation of vortices in the vortex tube. From several existing studies, the type of outlet hole in this tube has not been thoroughly studied. From the analysis results, it can be seen the difference in the results of each outlet size in the tube basin. With this question, this study aims to determine the strength of the vortex of the parameters that must be looked for, namely Water Flow Discharge (m3 / s), velocity (m / s), and Total Head Water (m). The vortex gravity system on a laboratory scale, based on previous studies or studies varying the diameter of the vortex tube and tube outlet hole, this study examined the effect of differences on the diameter of the vortex tube and the outlet hole of the tube basin. From the calculation of the vortex strength at the outlet hole of 25 cm, the results of the vortex strength are 7.53 m2 / s; 22.60 m2 / s; 45.21 m2 / s; 52.75 m2 / s. After that, proceed with the calculation of the outlet hole of 30 cm, the results of the vortex strength are 12.24 m2 / s; 28.26 m2 / s; 45.21 m2 / s; 56.52 m2 / s. Furthermore, the calculation at the 35 cm outlet hole obtained the vortex strength of 14.13 m2 / s; 30.14 m2 / s; 42.39 m2 / s; 60.28 m2 / s. the occurrence of fluctuation in the vortex strength results due to the energy available in the extracted water flow after hitting the outlet hole in the vortex tube. The graph produced in this calculation shows that the highest vortex strength occurs in a tube with a diameter of 35 cm.

Encoding Energy-Density as Geometry

Physicists possess an intuitive awareness of Euclidian space and time and Galilean transformation, and are then challenged with Minkowski space-time and Einstein’s curved space-time. Relativistic experiments support the “time-dilation” interpretation and others support “curved space-time” interpretation. In this, and related work, we investigate the key issues in terms of the intuitive space-time frame. In particular, we provide alternative approaches to explain “time dilation” and to explain the energy density for gravity systems. We approach the latter problem from an information perspective.

Hemijska svojstva dugotrajno zalivanih livadskih zemljišta doline Belog Drima u području Kline

The impact of long-term (> 100 yr) irrigation on soil chemical properties was studied on eight plots in the Beli Drim river valley in Kosovo and Metohija near Klina, Serbia. For these studies, soil samples from shallow profiles were collected from only one or two depth zones of the Ah horizon; and from moderately deep and deep profiles, from two to three depth zones for the purpose of comparing irrigated field and non-irrigated meadow lands. Water from the Beli Drim River and surface gravity systems (irrigation furrows or border strip irrigation) were used for irrigation. Chemical variables included determination of pH-H2O, content of CaCO3, content of humus, hydrolytic acidity, sum of basic cations, cation exchange capacity, and base saturation. On irrigated soils, the results of chemical analysis showed on average a small increase in pH-H2O (0.07 pH units), as well as a significant decrease in humus content (2.00-4.75%), sum of basic cations (4.98-12.98%) and cation exchange capacity (12.8%) compared to the non-irrigated land of the study area. Long-term irrigation had no effect on hydrolytic acidity and base saturation in the Ah horizon of the investigated lands. Namely, the mentioned variations in the chemical properties of the investigated soils show that slight processes of reduction in the humus content and reduction of the content of base cations occured. Data on the chemical properties of the investigated soils indicate that the destructive processes of reduction in the humus content and leaching of base cations must be controlled in order to achieve a stable sustainable system of high productivity and prevent their further deterioration.

Research on Evolution Pattern and Spatial Correlation between Economic Development and Environmental Pollution Centers of Gravity

The coordinated development of environment and economy is an important way to achieve sustainable development. As the Guangdong-Hong Kong-Macao Greater Bay Area has been included in the national agenda, Guangdong province faces a turning point in its economic, social, and environmental development. Taking Guangdong province as an example, this paper analyzes the spatial evolution and correlation of economic development and environmental pollution by means of center of gravity (COG) and geo-information system (GIS). The results show the shift of economic development COGs are smaller than that of environmental pollution. Environmental pollution COGs are negatively correlated with economic scale and quality COGs, whereas it is positively correlated with economic growth COG, which depends on the industrial structure and local policies. The continuous transformation of the industrial structure of the Pearl River Delta Region (PRD) is conducive to improving its environment and promoting economic development of Non-Pearl River Delta Region in Guangdong province (Non-PRD) through bilateral causality. As the receiving place of industrial transfer, eastern Guangdong has obvious effects of environmental pollution transfer from the secondary industries. In this study, the logical spatial evolution path of the economic development and environmental pollution COGs is established. It provides theoretical and practical references for the study of interrelationship between economy and environment.