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A New Under-Frequency Load Shedding Method Using the Voltage Electrical Distance and Artificial Neural Networks

A New Under-Frequency Load Shedding Method Using the Voltage Electrical Distance and Artificial Neural Networks

Abstract—This paper proposes a method for determining location to shed the load in order to recover the frequency back to the allowable range. Prioritize distribution of the load shedding at load bus positions based on the voltage electrical distance between the outage generator and the loads. The nearer the load bus from the outage generator is, the sooner the load bus will shed and vice versa. Finally, by selecting the rate of change of generation active power, rate of change of active power of load, rate of change of frequency, rate of change of branches active power and rate of change of voltage in the system as the input to an Artificial Neural Network , the generators outage, the load shedding bus are determined in a short period of time to maintain the stability of the system. With this technique, a large amount of load shedding could be avoided, hence, saved from economic losses. The effectiveness of the proposed method tested on the IEEE 39 Bus New England has demonstrated the effectiveness of this method.
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ROYAL INSTITUTE OF TECHNOLOGY KUNGL TEKNISKA HÖGSKOLAN. Department of Signals, Sensors & Systems Signal Processing S STOCKHOLM

ROYAL INSTITUTE OF TECHNOLOGY KUNGL TEKNISKA HÖGSKOLAN. Department of Signals, Sensors & Systems Signal Processing S STOCKHOLM

In the signal processing literature, several estimators have been proposed for estimation of the frequency rate-of-change of complex-valued linear frequency modulated signals from noisy discrete time observations. An early reference is [1], and a comprehensive survey of instantaneous frequency estimators is given in [2]. Recent work includes FFT based methods that utilize the polynomial phase transform, [3], [4], and methods that utilize the, so called, Tretter approximation, [5], including the estimators in [6], [7], [8], and methods based on fourth order sample moments, [9].
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Frequency rate of divorce in Malir district, Karachi, Pakistan

Frequency rate of divorce in Malir district, Karachi, Pakistan

1970, there was no provision for divorce in Italian law, and the difficulty of ridding oneself of an unwanted spouse in the absence of any legal way to do so was a frequent topic of drama and humor, reaching its apotheosis in the 1961 film Divorce, Italian Style. In Italy, almost all divorces are granted on the ground of legal separation. In 2015, the period of legal separation was reduced to one year, and six months in the case of consensual separation (from the previous three years), (http://www. reuters.com/article/2015/04/23/us-italy-divorce- idUSKBN0 NE1JD20150423) since the comparition of the spouses at the first hearing in the separation procedure or since the date of the separation agreement. A separation decree may be granted when there are facts that would render the continuation of married life intolerable or have a serious and damaging impact on the upbringing of the children. Separation may also be granted by mutual consent. Separation by mutual consent and uncontested divorce are also possible without judicial procedure. Divorce may be granted without a previous legal separation only in very rare cases (e.g. final criminal conviction, annulment or divorce obtained abroad by the foreign spouse, unconsummated marriage, sex change). In Japan, there are four types of divorce: Divorce by Mutual Consent, Divorce by Family Court Mediation, Divorce by Family court Judgment, and Divorce by District Court Judgment. (People statistics - divorce rate by country 2004) (24)
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Investigating the Relationship Between Student Difficulties with the Concept of Electric Potential and the Concept of Rate of Change

Investigating the Relationship Between Student Difficulties with the Concept of Electric Potential and the Concept of Rate of Change

One area that is often studied that involves rate of change is that of students’ ability to make and analyze graphs. Nemirovsky and Rubin 10 looked at the difficulties high school students have in explaining the relationship between a function and its derivative. The researchers interviewed high school students who had not yet taken calculus and presented an analysis based on the interviews of six of these students. Two seventy five minute interviews were conducted for each student. The interviews were based on 15 problems the students were to construct functions and their derivatives in one of three different contexts. The researchers used the three different contexts of motion, fluids, and number-change in an attempt to study rate of change in graphs and see if context had a large influence. For each context, the students created graphs using computers. For the context of motion, a small car and a motion detector were used to produce graphs that would be examined. Fluid was studied with a bag that air could be put into or removed at different rates with an air flow monitor connected to a computer. For each context, parallel problems were presented. Comparing a velocity graph to a position graph in the motion context was parallel to comparing a flow rate vs. volume graph as well as B vs. x corresponding to A vs. x for number-change.
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Analysis of Chinese Short Term International Capital Flow Capital Motivation

Analysis of Chinese Short Term International Capital Flow Capital Motivation

Chen Xuebin (2007) empirically analyzed the situation of China’s internation- al capital flows from 2000 to early 2007 by establishing a cointegration equation for China’s long-term and short-term capital inflows. It was found that the strong appreciation of the RMB is expected to be attractive to short-term capital inflows [7]. Chen Langnan (2009) proposed that the RMB exchange rate, domes- tic and international spreads and real estate yields have significant lag effects on short-term international capital flows. In the long run, the expected rate of change of RMB exchange rate and domestic and international spreads are sig- nificant factors affecting short-term international capital flows. The RMB ex- change rate, domestic stock market returns and real estate yields have not had a significant impact on short-term international capital flows [8]. Liu Liya (2013) examined the relationship between capital controls and international capital flows. The empirical results show that capital controls will increase domestic output shocks, resulting in very limited effect of capital controls on international capital flows [9].
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Currency substitution in Romania

Currency substitution in Romania

It is very important to make the distinction between dollarization and currency substitution. Dollarization has many definitions. Some authors view dollarization as the currency substitution phenomenon in Latin American area. Calvo and Veight (1992) view currency substitution as normally constituting a late stage of the dollarization process. For a few Latin American countries the dollarization debate is linked to the issue of a currency board. Arguments state that a currency board could reduce transaction costs, enhance policy credibility, and reduce sovereign risk. The cons are the loss of the exchange rate instrument to buffer the economy against real or external shocks, loss of seignorage revenues, and the loss for the central bank of the lender of last resort function.
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A study of the controllability of air movements in predominantly naturally ventilated houses

A study of the controllability of air movements in predominantly naturally ventilated houses

The environmental side was always chosen to be the cooler of the two sides. Once the connecting door was opened, warm air flowed from the design to the environmental side, and cool air flowed from the opposite direction. Thus from time zero of the measurement period, there was a tendency for any initial temperature difference between the two sides to lessen with time. The rate at which this occured was not constant, since it depended upon the temperature conditions pertaining at the time, and also the setting of the door. At larger temperature differences, for example, the rate would be greater than at lower temperature differences. At these highest temperature differences ( 30 c ), this could be in the region of a 5 c lowering of the initial temperature difference, over a typical 20 minute period.
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Evolution POWERPOINT

Evolution POWERPOINT

Evolution only happens when there is a change in the gene frequency within a population over time?. • When the frequency of.[r]

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Adaptive underfrequency load shedding based on real time simulation

Adaptive underfrequency load shedding based on real time simulation

Since the amount of power to be shed is determined to be constant without taking the disturbance location into consideration, the conventional UFLS may shed more or less power than required, in this case frequency overshoot could occur. On the other hand, adaptive UFLS uses rate of change of frequency information from all the generators PMUs to compute the amount of disturbance power in real time. Several adaptive UFLS have been reported in the literature (Anderson & Mirheydar, 1992) - (Pasand & Seyedi, 2007) to overcome the deterministic nature of the conventional UFLS (Seethalekshmi et al., 2011).
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BIOL 692H_v5_NM_EN.pdf

BIOL 692H_v5_NM_EN.pdf

Although the results showed many promising trends in terms of capturing the interaction between the applied electric field and the neural activity, not all of them were significant. These trends might grow and become significant if we increase the number of samples or perform analysis on the channel level instead of the slice level. Our preliminary investigation showed that not all 59 recorded channels from a slice have reliable recordings during the entire course of the experiment. Some of the channels have a partially successful recording rather than a complete one during the 35-minute course of the experiment. We propose that the next series of analysis should be performed by excluding the affected channels. An issue specific to the 2Hz-ACS experiments was that while the endogenous frequency was different between slices (0.5 – 4 Hz), we always stimulated them with 2Hz. The stimulation frequency could be customized to the endogenous frequency of the slice over the pre-stimulation period.
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Chapter 3_2.pptx

Chapter 3_2.pptx

Determine the rate of change of iPod sales in 2008 using the model. Provide the units for the rate of change[r]

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A Novel Magnetoelastic Immunosensor for Ultrasensitively Detecting Carcinoembryonic Antigen

A Novel Magnetoelastic Immunosensor for Ultrasensitively Detecting Carcinoembryonic Antigen

the initial mass, △m is the mass change, and △f is the shift in the resonance frequency of the sensor. Equation 2 shows that sensor sensitivity ( △f / △m ) is inversely propor- tional to initial magnetoelastic mass (M) of the sensor. Sensors with smaller physical dimensions have a lower ini- tial mass resulting in higher sensitivity. The negative sign in the equation represents a decrease in frequency ( △f ) to an addition of non-magnetoelastic mass ( △m ) on the sen- sor. Hence, binding of the target organisms onto the bio- sensor surface causes a mass increase with a corresponding decrease in fundamental resonance frequency.
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Factors associated with change in exacerbation frequency in COPD

Factors associated with change in exacerbation frequency in COPD

exacerbation frequency means that patient recall of events in the previous year can be used to categorize patients as having frequent (FE) or infrequent (IE) exa- cerbations during the subsequent year [7,10]. These cat- egories are now recognised as important COPD patient phenotypes that influence the clinical management of the patient [11]. Although exacerbation frequency is relatively stable in most patients, some year on year vari- ation exists and the factors associated with any change in category have not yet been investigated. Therefore we analysed the data from the “Evaluation of COPD lon- gitudinally to identify predictive surrogate endpoints (ECLIPSE)” study to determine whether patients kept or changed their IE or FE category. Previously, three groups of 0, 1 and 2+ exacerbations per a year have been de- scribed [7] but interpretation of the nine potential tran- sitions would be complex and less clinically relevant. In this study, we have also examined a slightly smaller group of 1832 patients who completed two years of
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Mathematical Analysis of Performance of a Vibratory Bowl Feeder for Feeding Buttons

Mathematical Analysis of Performance of a Vibratory Bowl Feeder for Feeding Buttons

Literature survey and past experience has shown that there are many part parameters, process parameters which could affect the performance of feeder. These parameters are part size, part population, frequency, part weight, part thickness, part material and shape. A number of trial experiments however revealed that frequency, part population and part size were the most significant process parameters and were therefore selected for the present study. The working ranges for these parameters were determined by using a series of trial runs. These ranges are shown in table 1. The lower limit is represented by -1 and the upper limit by +1.
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Do Announcements of Dividend Payment Frequency Change Matter?

Do Announcements of Dividend Payment Frequency Change Matter?

By looking through our event study distribution data, majority of changes in payout frequency are announced jointly with a contemporaneous increase or decrease in total dividend amount, which might result in significant effect on the stock return behavior. We predict in Hypothesis 1(a) that the favorable market reactions to frequency increase will be greater if the firm increases dividend payment amount at the same time. Thus, it is essential to control for the influence of the changes in overall dividend payment when we are testing the correlation between frequency change and announcement period abnormal returns. Moreover, there may be other firm-level characteristics that might affect the firm stock performance during the announcement period. In the following step we further analyse what fraction of the abnormal stock return effects can be explained by the firm event of frequency change, and what fraction can be explained by other firm related factors. Following the previous empirical research by Ferris et al. (2010), we conduct a multivariate analysis with a number of firm specific characteristics selected as control variables. By regressing the cumulative abnormal returns (CARs) in various event windows on the occurrence of frequency change with the control of other influencing factors, we are able to correctly measure the event period cumulative abnormal returns related to the frequency change and get an approximation on what may drive investor sentiment.
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Is climate change causing increased rockfall frequency in Austria?

Is climate change causing increased rockfall frequency in Austria?

Rockfalls are a considerable threat to settlements and in- frastructure in the Alps. The number of media reports on hazardous rockfalls and other geomorphic events has in- creased in recent years and the amplifying role of climate change is frequently suggested if not stated as de facto. This is exemplified by newspaper headlines such as Will climate change crush our Alps? (“Zerbricht der Klimawandel unsere Alpen?”, Bild.de, 2011). In the context of a tragic rockfall event in Bavaria that cost two lives (Bild.de, 2010), the Pres- ident of the Bavarian State Office for the Environment (LFU) stated in an interview that higher rainfall and a more rapid succession of cold and warm phases would accelerate erosion and rockfall, and that we are currently experiencing a “desta- bilisation of our mountain regions”. In scientific publica- tions, the question of currently-intensifying natural hazards in mountain regions is also a matter of debate (Berz, 2009). Rockfall is presumed to be a direct and perhaps unexpectedly
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School of Physical, Environmental and Mathematical Sciences University College The University of New South Wales Australian Defence Force Academy Canberra ACT 2600 Australia

School of Physical, Environmental and Mathematical Sciences University College The University of New South Wales Australian Defence Force Academy Canberra ACT 2600 Australia

In the lab Understanding the Derivative , we investigated the instantaneous rate of change of a function, that is the rate of change at a particular value of the independent variable ( t[r]

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Revisiting the Derivative: Implications on the Rate of Change Analysis

Revisiting the Derivative: Implications on the Rate of Change Analysis

We are dealing with a mathematical concept, therefore the definition that best suites our needs is definition number 3, in particularly definition 3b, “the instantaneous rate of change of a function with respect to its variable,” after all that is what is important to scientists, be they natural scientists or social scientists, any scientist who must deal with rates of change and functions that determine the growth of variables. Being an economist, I shall endeavor to solve the issues that this paper raises in an economic fashion, but no doubt they imply to all sciences that deal with a rate of change. Accuracy is fundamental in any science, precision is what this paper attempts to get to.
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VAT rate change and its impact on liquidity

VAT rate change and its impact on liquidity

The impact of the tax system on business activities of a company is an important component of the fiscal policy. Previous researches on the impact of tax rate changes on business activities of a company have been quite long- lasting. Researches on the impact of tax rate changes on the corporate income tax date back to Modigliani and Miller (Gordon and Lee, 2000). Lately, since the data at the micro level has become more accessible to the public, researches have been conducted more frequently. Previous researches on the impact of tax on business activities of a company have been mainly related to the impact of corporate income tax change on profitability of business and rarely included the Republic of Croatia. Similarly to profitability, there has not been any significant research on the effect of value added tax change on liquidity of Croatian companies. Researches on the effect of Value Added Tax on company's business are not so frequent.
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Determinants of Corporate Investment: Post Liberalization Panel Data Evidence from Indian Firms

Determinants of Corporate Investment: Post Liberalization Panel Data Evidence from Indian Firms

India faced different financial environment during 1965-78. Athey and Reeser (2000) using a panel of 142 firms from 7 industrial groups in India over the period 1981-96 found that cash flow is more important for firms with limited access to capital markets. Is there still a binding finance constraint on firm investment activities in India? In another recent study Kumar et al. (2001) attempted to investigate the presence of finance constraints among investing firms in the post- liberalization period 1993-98, using Indian manufacturing firms as a case study. The authors suggested that exporting firms faced less restrictive finance constraints than their domestic counterparts. The sales accelerator was significant for domestic and small firms. It was not found significant for the exporting firms. Another important study in the Indian context is of Athukorala and Sen (2002) who examined the determinants of private corporate investment using data for the period 1954-96. These authors found lagged change in real bank credit to be an important source of external finance to Indian firms. Public investment has a strong complimentary relationship with private corporate investment in India.
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