simplified physics-based model

Top PDF simplified physics-based model:

A Model of Dark Matter and Dark Energy Based on Relativizing Newton’s Physics

A Model of Dark Matter and Dark Energy Based on Relativizing Newton’s Physics

It is worthwhile to stress that the cosmology proposed here is based on a very simplified model, in which galaxies, or even galaxy-clusters, are represented as point masses receding rectilinearly along the line of sight of an observer on Earth. Real galaxies and galaxy structures are in rotation relative to an Earth’s observer, and the stars and planets in each galaxy are also in continuous rotation. The ob- served rotations of all celestial structures are major sources of dark and quantum matter. The process of their production due to the structures’ rotational motion could be analyzed in a similar way to the current analysis. We have already em- barked on the analysis of the production of dark and quantum matter due to ro- tational motion, and of the spatial entanglement between the dark matter dis- persed spherically at their halos. We conjecture that the physical entanglement of dark matter in space is medium by which gravitational forces between bodies are enacted. It is well accepted that dark matter is the “gravitational glue” that keeps galaxies and galaxy structures bound together. Our preliminary analysis confirms this.
Show more

26 Read more

Improving the snow physics of WEB DHM and its point evaluation at the SnowMIP sites

Improving the snow physics of WEB DHM and its point evaluation at the SnowMIP sites

Abstract. In this study, the snow physics of a dis- tributed biosphere hydrological model, referred to as the Water and Energy Budget based Distributed Hydrological Model (WEB-DHM) is significantly improved by incor- porating the three-layer physically based energy balance snowmelt model of Simplified Simple Biosphere 3 (SSiB3) and the Biosphere-Atmosphere Transfer Scheme (BATS) albedo scheme. WEB-DHM with improved snow physics is hereafter termed WEB-DHM-S. Since the in-situ observa- tions of spatially-distributed snow variables with high res- olution are currently not available over large regions, the new distributed system (WEB-DHM-S) is at first rigorously tested with comprehensive point measurements. The stations used for evaluation comprise the four open sites of the Snow Model Intercomparison Project (SnowMIP) phase 1 with dif- ferent climate characteristics (Col de Porte in France, Weiss- fluhjoch in Switzerland, Goose Bay in Canada and Sleep- ers River in USA) and one open/forest site of the SnowMIP phase 2 (Hitsujigaoka in Japan). The comparisons of the snow depth, snow water equivalent, surface temperature, snow albedo and snowmelt runoff at the SnowMIP1 sites reveal that WEB-DHM-S, in general, is capable of sim- ulating the internal snow process better than the original WEB-DHM. Sensitivity tests (through incremental addition of model processes) are performed to illustrate the necessity of improvements over WEB-DHM and indicate that both the 3-layer snow module and the new albedo scheme are essen- tial. The canopy effects on snow processes are studied at the Hitsujigaoka site of the SnowMIP2 showing that the snow holding capacity of the canopy plays a vital role in simulat- ing the snow depth on ground. Through these point evalua-
Show more

18 Read more

Animation, simulation, and control of soft characters using layered representations and simplified physics-based methods

Animation, simulation, and control of soft characters using layered representations and simplified physics-based methods

This paper presents a robust, adaptive method for animating dy- namic visco-elastic deformable objects that provides a guaranteed frame rate. Our approach uses a novel automatic space and time adaptive level of detail technique, in combination with a large- displacement (Green) strain tensor formulation. The body is par- titioned in a non-nested multiresolution hierarchy of tetrahedral meshes. The local resolution is determined by a quality condi- tion that indicates where and when the resolution is too coarse. As the object moves and deforms, the sampling is refined to concen- trate the computational load into the regions that deform the most. Our model consists of a continuous differential equation that is solved using a local explicit finite element method. We demon- strate that our adaptive Green strain tensor formulation suppresses unwanted artifacts in the dynamic behavior, compared to adaptive mass-spring and other adaptive approaches. In particular, damped elastic vibration modes are shown to be nearly unchanged for sev- eral levels of refinement. Results are presented in the context of a virtual reality system. The user interacts in real-time with the dy- namic object through the control of a rigid tool, attached to a haptic device driven with forces derived from the method.
Show more

195 Read more

A new simplified vector-based model to support solar energy planning at urban scale

A new simplified vector-based model to support solar energy planning at urban scale

A key element for the prediction of dynamic PV yield is predicting PV cell operational temperature that impacts PV system efficiency. Different models, ranging from high-fidelity physics-based models to simplified models, have been developed to predict PV cell operational temperature (Skoplaki et al., 2009; Dubey et al., 2013). Existing models can be grouped into two types: (1) physics-based models, and (2) statistical models. Physics-based methods are the most studied in the field, and a large number of models have been published in existing research papers. These models are based on a simplified form of the physical model and include correlation coefficients that capture the effect of key physical variables to simplify certain parts of the physical model. Statistical models, on the other hand, require fewer inputs as they are typically based on the simplest mathematical equation, often derived from the physical model, and derive unknown model coefficients by fitting the model to the measured PV yield data. Some of the latest statistical models use artificial intelligent methods to predict the PV cell operating temperature. Therefore, a key difference between the physics-based models and the statistical models is whether input parameters of the specific PV module are required. Physic- based models either demand detailed parameters such as solar transmittance and solar absorptance of the PV module, or require semi-empirical coefficients depending on the specific PV modules. Meanwhile, statistical models do not require any input of PV module-related parameters and usually only demand inputs of the surrounding weather conditions. Further discussion of these models and methods will be provided in the subsections.
Show more

148 Read more

Classical E&M Model for Nonlinear Optics - Applications to the Generation of Harmonic and Terahertz

Classical E&M Model for Nonlinear Optics - Applications to the Generation of Harmonic and Terahertz

The generation of terahertz (THz) radiation by irradiating semiconductors with ultrafast pulses in the 800 nm wavelength range has been extensively investigated owing to the lack of convenient alternative sources of these potentially useful frequencies [1-6]. Descriptions of THz generation include the current-surge model of Shan and Heinz [5, 6] for free carriers and the frequency-mixing approach of Morris and Shen [8] and Khurgan [9] for bound charges. The former accounts well for the frequency dependence and magnetic field enhancement of the radiation when free carriers are present, but contains no means of generating azimuthal dependences [4, 7]. The latter provide phenomenological descriptions of the azimuthal dependence, but not the free-carrier background. Saeta et al. [1] attempted to separate these contributions from data, but performed the calculation at the intensity, not the field, level. Since the two contributions are driven coherently by a common field, an intensity calculation does not properly combine them. The purpose of Ch. V. is to investigate the consequences of a coherent superposition at the field level, using a simple dipole-radiation model that provides insight into the origin of the bulk response. Analytic expressions for the combination are obtained.
Show more

123 Read more

Monetary part of Abenomics: a simplified model

Monetary part of Abenomics: a simplified model

Presented is a simplified mathematical model that describes dynamics developing on financial market after the liquidity pumping. The model is used to examine theoretical and practical implications of the monetary component of Abenomics. Based on the theoretical considerations, proposed is a somewhat practical suggestion how to increase the efficiency of Abenomics’ monetary policy.

15 Read more

A Simplified Chinese Parser with Factored Model

A Simplified Chinese Parser with Factored Model

end, we define a specific head propagation table using the TregEx tool after classifying the grammar rules and counting the frequency of some related tags. Which differs from the work of (Magerman, 1995) and (Collins, 1999) that the rules of head finding are defined based on lin- guistic knowledge. There are three steps to gen- erate the head propagation table. Firstly, we ex- tract all the grammar rules from the TCT corpus, and then classify the rules according to their par- ent nodes. Secondly, we calculate the frequency of each sort of child node that have the same par- ent node, then select the higher frequency child nodes as the candidate head word. For example, under the ap (adjective phrase) node, we get some relatively high frequency child nodes by counting showed in the table 2. Thirdly, we search the matched sub-trees that the candidate head is the real head in the TCT Treebank by using the TregEx specified pattern (Levy, 2006). Finally, through the distribution of the amount of the matched tree fragment, we generate the head propagation table and every child node is as- signed with a priority score and direction. The Parent Node Child Node Frequency
Show more

6 Read more

A SIMPLIFIED REVIEW OF ROMER’S (1990) MODEL

A SIMPLIFIED REVIEW OF ROMER’S (1990) MODEL

This paper analyzes Romer’s(1990) model without any argue to Romer’s growth model and conundrum surrounds the growth matter. The model filled gap in the literature and enhances economists’ considerate an endogenous technological change. However, given its complexity and difficult to demonstrate how the level of R&D is determined in the general market equilibrium within the Romer model. This paper provides a simplified way to understand the Romer model by presenting both consumption and production sides of the economy, the latter is made up of three productive sectors: the final goods, producer durables and R&D sectors. The paper also derives step by step all sectors but not too far ahead in entire advanced mathematical calculus and algebra for the intuition purpose. Thus, this layout sheds light on the Romer model and become more accessible to enhance the theory of the knowledge- based economy.
Show more

12 Read more

Secular stagnation and decline: a simplified model

Secular stagnation and decline: a simplified model

Presented is a mathematical model of single-product economy describing a nominal economic growth and a nominal economic decline. Based on the model of economic dynamics, policies handling the gravity of the secular stagnation are furnished. First, transition of the secular stagnation into the secular decline is to be prevented. Second, a two-stage economic policy against the secular stagnation should be entertained. The first stage is to promote a policy of advancing the additional demand for products to counterbalance the additional supply of products by external suppliers. The second stage is to sustain a policy of savings and investments to stipulate an economic growth where the savings and investments are to be committed with a modest acceleration. Two stages of the alleviating economic policy can be executed concurrently.
Show more

35 Read more

Model Transformation Using a Simplified Metamodel

Model Transformation Using a Simplified Metamodel

AndroMDA is a code generation tool that takes a UML model as input and generates source code as output. It adopts a template-based transformation methodology similar to ours in a degree but differs significantly in handling of metamodel. Compared to direct-manipu- lation transformation, the structure of a template resem- bles more closely the code to be generated. Templates lend themselves to iterative development as they can be easily derived from examples. Since the template ap- proaches discussed in this section operate on text, the patterns they contain are untyped and can represent syn- tactically or semantically incorrect code fragments. On the other hand, textual templates are independent of the target language and simplify the generation of any tex- tual artifacts, including documentation.
Show more

8 Read more

A simplified mathematical model for thrombin generation

A simplified mathematical model for thrombin generation

In the absence 243 of inhibition case 2 and case 3, the time interval between the end of the initiation phase and 244 the moment that thrombin concentration reaches its maximum value is [r]

36 Read more

A simplified mathematical model for thrombin generation

A simplified mathematical model for thrombin generation

Permanent repository link: http://openaccess.city.ac.uk/13568/ Link to published version: http://dx.doi.org/10.1016/j.medengphy.2013.10.012 Copyright and reuse: City Research Online aims[r]

6 Read more

Applying a Grammar Based Language Model to a Simplified Broadcast News Transcription Task

Applying a Grammar Based Language Model to a Simplified Broadcast News Transcription Task

We propose a language model based on a precise, linguistically motivated grammar (a hand-crafted Head-driven Phrase Structure Grammar) and a statistical model estimating the probability of a parse tree. The language model is applied by means of an N-best rescor- ing step, which allows to directly measure the performance gains relative to the baseline sys- tem without rescoring. To demonstrate that our approach is feasible and beneficial for non-trivial broad-domain speech recognition tasks, we applied it to a simplified German broadcast-news transcription task. We report a significant reduction in word error rate com- pared to a state-of-the-art baseline system.
Show more

8 Read more

A Simplified Perturbation Model for Prediction of Mean Ionic Activity Coefficient in Aqueous Electrolyte Solution

A Simplified Perturbation Model for Prediction of Mean Ionic Activity Coefficient in Aqueous Electrolyte Solution

state has been utilized as a reference system. Dipole-dipole and Lennard-Jones interactions have been considered in perturbation term. The activity coefficients of more than 240 data points for aqueous amino acid- electrolyte solution have been modeled by the minimum number of adjustable parameters which had been set on dielectric constants. Results of the model denote that the effect of reference term in chemical potential of amino acids is significant. Compared to similar models, the modifications caused an improvement in the results of the perturbation model. The results of this work show that with the simplified perturbation model, the mean ionic activity coefficient of electrolyte in aqueous solution of amino acids can be calculated in a very simple way, especially for ternary systems.
Show more

13 Read more

Issues on Measurement the Benefits of Improved Highway Infrastructure

Issues on Measurement the Benefits of Improved Highway Infrastructure

The paper reviews the theoretical and empirical issues on the measurement of the impacts of the performance of the improved highway infrastructure. It focuses on experience with the notion of the assessment of so called direct benefits associated with the investments rather than the estimation of the indirect ones in context of so popular in practice cost-benefit analysis generating a huge literature in its own right. Raising the issues of validity of the intervention of governments into economics in terms of social justice, the concept of public alternative costs is discussed. Concluding that the inadequate usage of public resources for the formation and development of highway infrastructure may have negative consequences on the dynamics and tendencies of the development of other economic sectors, the question of an adequate, socially and economically reasonable assessment of development is raised. Despite the fact that the cost-benefit analysis is the method by which this concept of efficiency can be applied to publicly supplied good it lacks clarity. In fact, the intangible costs and benefits never enter the analysis. It is suited only for ranking courses of action designed to attain the same ends so the real benefits of decisions will be speculative and uncertain. Taking into account the complexity of the interaction the authors of the article focus on the research of the methodological framework of the evaluation of the benefits of the public in the result highway system modification. The research is based on the improvement of the simplified general equilibrium model which focuses at the price effects of direct changes in transport costs and their measurement. The research results may answer the question if the accomplishment of tasks set for the system or its parts meet the society (which uses or is a neighbor to that infrastructure )needs. Other aspects are going to be excluded from this initial investigation.
Show more

8 Read more

LEARNING MODEL AND INTELEGENCI INFLUENCE ON LEARNING ACHIEVEMENTS OF PHYSICS STUDENTS OF JUNIOR HIGH SCHOOL IN THE CITY OF MANADO

LEARNING MODEL AND INTELEGENCI INFLUENCE ON LEARNING ACHIEVEMENTS OF PHYSICS STUDENTS OF JUNIOR HIGH SCHOOL IN THE CITY OF MANADO

Physics as one of the branches of natural science Knowledge (IPA) are more concerned with activities such as collecting data, measuring, calculating, analyzing, searching for relationships, linking concepts, are all aimed at one settlement of the problem. Therefore, the studied physics with high achievement, should not just memorize the theory, definitions and the like, but requires truly understanding. Theoretical physics is not just simply read for learning Physics not only to remember but to be understood to be implemented in everyday life, so expect students to explain and solve the problems There are. Mundilarto (2002:5) says that the subjects of physics aims so that students are able to master the concepts, principles or laws of Physics then expected students to compose their own returns in accordance with the level of maturity and his intellectual development. Learning Physics is based with the scientific attitude to solve problems that it faces, making it more aware of the Majesty of God Almighty. Physics must be understood in a way such that opprtunities for use in break right issue.
Show more

22 Read more

Monosodium urate crystal deposition associated with the progress of radiographic grade at the sacroiliac joint in axial SpA: a dual energy CT study

Monosodium urate crystal deposition associated with the progress of radiographic grade at the sacroiliac joint in axial SpA: a dual energy CT study

computed tomography (DECT) has recently been used to analyse the deposition of monosodium urate (MSU) crystals with higher sensitivity and specificity. However, it remains unclear whether the existence of the MSU crystal deposition detected by DECT at the sacroiliac joint in patients with AxSpA also is associated with the existing structural damage. Here, we performed this study to show the DECT MSU crystal deposits in AxSpA patients without coexisting gout and to ascertain the relationship between the MSU crystal deposition and the structural joint damage of sacroiliac joints. Methods: One hundred and eighty-six AxSpA patients without coexisting gout were recruited. The plain radiographs of the sacroiliac joint were obtained, along with the DECT scans at the pelvis and the clinical variables. All statistics based on the left or right sacroiliac joint damage grading (0 – 4) were calculated independently. Bivariate analysis and ordinal logistic regression was performed between the clinical features and radiographic grades at the sacroiliac joint. Results: At the pelvis, large quantities of MSU crystal deposition were found in patients with AxSpA. The average MSU crystal volume at the left sacroiliac joint, the right sacroiliac joint, and the pelvis were 0.902 ± 1.345, 1.074 ± 1.878, and 5. 272 ± 9.044 cm 3 , values which were correlated with serum uric acid concentrations (r = 0.727, 0.740, 0.896; p < 0.001). In bivariate analysis, wide clinical variables were associated with the changes in sacroiliac joint damage. Further, the AxSpA duration, BASFI score, and the volume of MSU crystal at both sides of sacroiliac joint were associated with the progress of radiographic grade at the sacroiliac joints in the ordinal logistic models (left AOR = 1.180, 3.800, 1.920; right AOR = 1. 190, 3.034, 1.418; p < 0.01).
Show more

12 Read more

Credit expansion and contraction: a simplified model

Credit expansion and contraction: a simplified model

During the credit expansion period of a limited length the amended demand exceeds the supply and that creates a product shortage on the market, which interrupts supply-demand equilibrium and drives the product price up. On the other hand, an increase of the product price decreases the product demand. As a general rule, the dual effect of price increase and demand decrease caused by the debt rising with a constant rate induces a restricted short-term nominal economic growth (see Krouglov, 2014). However, depending on the model characteristics, the said dual effect can cause either a nominal economic growth or a nominal economic decline of finite value (e.g., short-time fluctuations can distort a growth pattern).
Show more

13 Read more

Economic growth and debt: a simplified model

Economic growth and debt: a simplified model

Presented is a mathematical model of single-product economy where an investment and debt are used to alter the demand for and supply of product. Explored is the dynamics of a nominal economic growth and decline. Examined are cases of a constant-rate growing debt and a constant-rate and constant-acceleration growing investment.

22 Read more

A Physics-based Large-signal Analytical Model for AlGaN/GaN HFETs

A Physics-based Large-signal Analytical Model for AlGaN/GaN HFETs

In this project, our complete physics-based DC and large-signal RF simulator for AlGaN/GaN HFETs is described in detail. The model includes a DC device module and an RF module of a large-signal circuit simulator. The flowchart of this project is shown in Fig.1.6. The DC module is physics-based and correctly accounts for several different kinds of carrier transport appropriate to the physics of the corresponding zones. These zones are discussed, modeled, solved, and verified separately, and then combined with appropriate boundary conditions. Models of nonlinear resistances, space-charge transportation and charge-deficit transport are presented qualitatively and quantitatively. The resulting analytic DC IV curves are shown to agree well with experimental data from an industrial AlGaN/GaN HFET. These modeled DC IV curves and transconductance curves are also shown to compactly predict ATLAS two-dimensional simulation results accurately without the need for any adjustable fitting parameters. The new model depends only on basic device structural dimensions, material properties, and impurity doping information.
Show more

180 Read more

Show all 10000 documents...