Top PDF Analysis of non-thermal velocities in the solar corona

Analysis of non-thermal velocities in the solar corona

Analysis of non-thermal velocities in the solar corona

sky, was put orthogonally to the local radial direction, at se- lected radial distances, r, and consecutively at different po- sitions exactly above the N, E, S, and W limbs (see Fig. 1 and Table 1). We used a dispersion similar to what was used by Tsubabi (1975); other parameters, such as the setup after the exit of the spectrograph, were similar to what has been used by Koutchmy et al. (1983) with the same instrument to obtain photographic time sequences to search for FeXIV oscillations. The resulting spectral dispersion was 4.05 pm per pixel, taking into account the 9 µm pixel size of the Ko- dak KAF 1602E chip. After the re-imaging Micro-Nikkor lens and a field lens, an almost perfectly flat field over the whole chip was obtained (no trace of vignetting effect could be detected over the whole field). The adjusted effective ex- posure time was 5 s, just enough to avoid any saturation of the chip and to provide the best signal-to-noise ratio over a 16-bit dynamic range. The cosmetic property of the cooled chip at −20 C was found to be excellent, judging from dif- ferent calibration spectra, including solar spectra taken with the diffuser put in the light path of the coronagraph. We ac- curately removed the bias and dark currents from each frame and for each selected position shown on Fig. 1. We consec- utively recorded five frames in order to improve, after av- eraging the set, the signal-to-noise ratio over profiles which were extracted from the resulting images. Before averag- ing, individual spectra were co-aligned with a precision of 1/10 of a pixel in the spectral direction (note that the ob- served shifts of the overall spectra never exceeded one pixel for each set) and geometric distortion effects were removed. Regarding the other direction, note that the instrument uses a 4-quadrant-cell system of guiding to keep the same region on the slit during the recordings of each set of spectra, although the viewing is the real factor limiting the spatial resolution. An additional smearing is produced by the temporal averag- ing (typically 2-min averages).
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Intermittent heating of the solar corona by MHD turbulence

Intermittent heating of the solar corona by MHD turbulence

Although Direct Numerical Simulations (DNS) of turbulence have been performed in the framework of coronal heating, they have strong limitations due to the complexity of the non- linear physics involved. The main problem is related to the fact that they are computationally much too expensive: in the space domain, their resolution (at most 1024 3 for MHD) is too low compared to what would be needed to simulate a system like the corona with very high Reynolds numbers, and in the time domain, they are too slow to produce long time series suitable for a statistical analysis. An improve- ment of DNS such as adaptive mesh refinement is not always sufficient because turbulence is not intermittent enough (the most refined grid would be necessary on a large part of the domain). Simulations in 1D (e.g. Suzuki and Inutsuka, 2005) or 2D have their own limitations on the geometry of the struc- tures they can simulate.
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The Effect of Booster-Mirror Reflector on the Thermal  Performance of a Truncated Pyramid Solar Thermal Cooker

The Effect of Booster-Mirror Reflector on the Thermal Performance of a Truncated Pyramid Solar Thermal Cooker

In this paper, the results and analysis of the performance of a truncated pyramid solar thermal cooker under two conditions are presented: booster-mirror reflector covered with black cloth, and booster-mirror reflector exposed to solar radiation. Results of the thermal performance tests show respective stagnation absorber plate temperatures of 145 o C and 137 o C. First/Second Figures of Merit are 0.120/0.346 and 0.125/0.400 respectively. The total heating times of 5.2 kg of water when reflector is covered with black cloth and when exposed to solar radiation are respectively 195 and 190 minutes. There is a nominal time reduction of 5 minutes in favour of the case when reflector is exposed to solar radiation, but in reality the time reduction could be as high as 30.5 minutes. In a similar vein, the difference in pot wall temperatures for corresponding water temperatures during sensible heating could be about 6 o C higher, and at boiling point this could be up to 11.6 o C. Thus, the overall thermal performance of the cooker when reflector is exposed to solar radiation is superior to its thermal performance when reflector is covered with black cloth. This superiority is manifested in improved values of the First and Second Figures of Merit, reduction in the overall heating and boiling times, and higher values of pot wall temperatures.
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Advances in the design of solar concentrators for thermal applications

Advances in the design of solar concentrators for thermal applications

Solar concentrating technologies are seen as an important part of the strategy to increase the production of both renewable electricity and heat. Several technologies have been proved to be technically feasible; commercial Parabolic Trough systems (PTR) have been in the lead in installed capacity in new power plants. One promising technology that has a lower investment cost per m 2 is the LFR, Linear Fresnel Reflector collector. First demonstration plants in Spain and in the USA, are proving the concept technically, but failing yet to be a generalised choice, since their global efficiency conversion is still low. CLFR technology said to be ”Etendue Matched” and designed to take full advantage of ideal non-imaging optics is very promising alternative. In fact, through a joint optimization of primary and secondary stages of concentration, it is possible to find an answer to this problem, practically doubling the achieved concentration in conventional LFR configurations, substantially reducing optical losses due to shading and blocking and taking advantage of a multi-receiver design (that is what ”C” stands for). The present paper explains the concept and describes the prototype being proposed for demonstration.
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An Advancement To The Security Level Through Galois Field In The Existing Password Based Technique Of Hiding Classified Information In Images

An Advancement To The Security Level Through Galois Field In The Existing Password Based Technique Of Hiding Classified Information In Images

Galois Field refers to a field in which there exists finitely many elements. It is particularly useful in translating computer data as they are represented in binary forms. Galois operations match those of regular maths. Addition, multiplication and logarithms are common Galois operations. Using the multiplication property of the Galois field an algorithm can be implemented to design an encoder. Mathematically 4 bit multiplication results in the 8 bit of the result but the Galois technique multiplication will result 4 bit resultant for 4 bit multiplication. As for the case of n bit multiplication it will result in n bit result.[13] In the information age, sharing and transfer of data has increased tremendously and usually the information exchange is done using open channels which can make it vulnerable to interception. The threat of an intruder accessing secret information has been a continuing concern for data communication experts [1]. Steganography (SG) is one of many techniques used to overcome this threat. It is a technique in which communication between two parties is done in a covert fashion using a cover object. SG is a very old practice for secret communication and can be traced back to techniques like invisible ink and microdots used by spies [2]. In general, the embedding operation in SG requires a digital medium to carry the data. Images and multimedia components, such as video and audio files, are widely used and exchanged through the internet.
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The Impact of the Expansion of the Bolsa Familia Program on the Time Allocation of Youths And Their Parents Lia Chitolina Miguel Nathan Foguel Naercio Menezes-Filho

The Impact of the Expansion of the Bolsa Familia Program on the Time Allocation of Youths And Their Parents Lia Chitolina Miguel Nathan Foguel Naercio Menezes-Filho

household, the program caused an increase of more than 11 percentage points in the probability of attending school. One possible reason for this increase in the estimated impact is the fact that his/her family is only receiving any transfers from the Bolsa Familia program because he/she is attending school. The fear of losing access to the program, which means that it may take time to come back to it in case of harder times ahead, may stimulate parents to monitor their kids’ school attendance more strongly. When these two features were combined — i.e. male youngsters who were the youngest child — the probability of attending school increased by 16.2 percentage points and it is statistically significant at the 1 per cent level.
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Analysis of quality and cost of FeSiMg treatment master alloy vs. cored wire in production of ductile cast iron

Analysis of quality and cost of FeSiMg treatment master alloy vs. cored wire in production of ductile cast iron

The results of studies on the use of FeSi5%Mg magnesium alloy in modern cored wire injection method for production of nodular and vermicular graphite cast irons were described. The injection of Mg cored wire length is a treatment method which can be used to process The injection of Mg cored wire length is a treatment method which can be used to process iron melted in an electric induction furnace. This paper describes the results of using a high-magnesium ferrosilicon alloy in cored wire (Mg recovery 47-70%) for the production of vermicular and nodular graphite cast irons at in at least 13 foundries. The results of calculations and experiments have indicated the length of the cored wire to be injected basing on the initial sulfur content and weight of the treated melt. The results of numerous trials have shown that the magnesium cored wire process can produce high quality nodular and vermicular graphite irons under the specific industrial conditions of the above mentioned foundries. It has also been proved that in the manufacture of nodular graphite iron, the cost of the nodulariser in the form of elastic cored wire is lower than the cost of the FeSiMg5 master alloys.
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Electronic Government In Democratic Public Service In One Door Integrated Permit Handling Services Agency In The City Of Samarinda

Electronic Government In Democratic Public Service In One Door Integrated Permit Handling Services Agency In The City Of Samarinda

As state institutions, it should be possible to present and make use of electronic government in the function of serving the community. The emphasis in information technology to avoid the digital gap in at least. The provision of better government services to residents, increase interaction with the business world and industry, through access to information for community empowerment, a more efficient government or management. The results of that is expected of a reduction in corruption, the increase in transparency, the increase in comfort, and rising income or reducing expenses. Based on the results of research. Electronic government in the context of the ability to look the ability to run the function of government electronic media and build partnerships with private not optimal it is marked with the need for the allocation of fund optimally and support to work jointly with private companies to more so handling equipment and support for the success of electronic government could be achieved. As an effort to harmonize the acceleration of the completion of work, the licensing of the city of Samarinda must be able to implement the interests of citizens as well as problems faced by. No service to stop because of the support of funding led to the ability to reform it weakened to find appropriate formulations to stiffness in public service is not of stagnation. According to results of the review Khidasseli in Sutedi (2010) that norms behavior officers public service providers (a code of conduct for public officials), who set about norms in an administrative authority: 1) The obligation to work in accordance with the rules of law and standards of conduct of relevance to its function, 2) The obligation to put themselves in a neutral of or free from the
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Factors Affecting The Adoption Of Mhealth In Maternal Health Care In Nakuru Provincial General Hospital

Factors Affecting The Adoption Of Mhealth In Maternal Health Care In Nakuru Provincial General Hospital

delivery systems [7]. Since then it has come to encompass any use of mobile telephony technology to address healthcare challenges such as access, quality, affordability, matching of resources, and behavioral norms [1]. mHealth technologies are a valuable partner in health care’s shift towards a delivery model that is patient-centered and value- based. Mobile technologies can help to facilitate that shift among clinicians, life scientists, and consumers by defining and directing the patient-centered model towards health care that is community-based, integrated, seamless, and assimilated into the daily lives of consumers accustomed to an ’on-demand’ environment. Globally, the demand for mHealth has also been growing. The global mHealth market was estimated at $1.2 billion in 2011 and experts project that the market’s value would increase to $11.8 billion by 2018, implying that the demand is growing at an annual growth rate of 39 percent. Kenya has been on the fore front in the application of the mobile phone technology platform in providing solution to the social problems in the community. Qiang [1] in a World Bank report on mobile applications for the health sector indicated that Kenya has been the cutting edge of the use of mobile technology for development, with its M-PESA mMoney scheme having become a model for similar programs around the world. However, the report revealed that, the country’s adoption of the mHealth technology remains low, while the landscape of the industry is changing rapidly as mHealth enterprises come and go. Half of the mHealth enterprises are less than two years old, and their commercial viability is still in question; only four percent are for profit, and none from any public sector are currently operating sustainably. Several mHealth programs in the country have been launched and run not for profit by the NGOs. For Instance, the Kenyan integrated mobile Maternal and Newborn Child Health information platform (KimMNCHip) which is a national scale effort to provide affordable and accessible mobile health solutions to all pregnant women and mothers with children under 5 everywhere in Kenya. It is run by a cross-sector partnership between the Government of Kenya, Safaricom, World Vision, Care, AMREF, and NetHope [8]. The programme was launched to make use of the 29.2 million mobile subscribers in Kenya on assumption that at least every household, has a phone therefore it is easy to reach the 41 million Kenyans through the mHealth platform.
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	Field Cancerisation of the Upper Aerodigestive Tract: Screening for Second Primary Cancers of the Oesophagus in Cancer Survivors

Field Cancerisation of the Upper Aerodigestive Tract: Screening for Second Primary Cancers of the Oesophagus in Cancer Survivors

Tobacco, alcohol, and betel quid are the main causes of squamous cell cancers of the upper aerodigestive tract. These substances can cause multifocal carcinogenesis leading to multiple synchronous or metachronous cancers of the oesophagus, head and neck region, and lungs (‘ield cancerisation’). Globally there are several million people who have survived either head and neck squamous cell cancer (HNSCC) or lung cancer (LC). HNSCC and LC survivors are at increased risk of developing second primary malignancies, including second primary cancers of the oesophagus. The risk of second primary oesophageal squamous cell cancer (OSCC) ranges from 8-30% in HNSCC patients. LC and HNSCC survivors should be ofered endoscopic surveillance of the oesophagus. Lugol chromoendoscopy is the traditional and best evaluated screening method to detect early squamous cell neoplasias of the oesophagus. More recently, narrow band imaging combined with magnifying endoscopy has been established as an alternative screening method in Asia. Low-dose chest computed tomography (CT) is the best evidence- based screening technique to detect (second primary) LC and to reduce LC-related mortality. Low-dose chest CT screening is therefore recommended in OSCC, HNSCC, and LC survivors. In addition, OSCC survivors should undergo periodic pharyngolaryngoscopy for early detection of second primary HNSCC. Secondary prevention aims at quitting smoking, betel quid chewing, and alcohol consumption. As ield cancerisation involves the oesophagus, the bronchi, and the head and neck region, the patients at risk are best surveilled and managed by an interdisciplinary team.
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Managament quality of tools in the planned housing casting

Managament quality of tools in the planned housing casting

Subbotko, Methods of distribution of tool at units based on TM software of Guhring, Production Engineering Wroc ł aw University of Technology,(2006) 273- 280 (in Polish).. Bocheński, C[r]

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Response of the AMOC to reduced solar radiation – the modulating role of atmospheric chemistry

Response of the AMOC to reduced solar radiation – the modulating role of atmospheric chemistry

Still, most of these studies are based on models with- out interactive atmospheric chemistry. The influence of cli- mate changes on the state of the ozone layer has long been recognized. The cooling of the stratosphere by greenhouse gases (GHGs) slows down catalytic ozone oxidation cy- cles, leading to ozone increase (e.g. Haigh and Pyle, 1982; Revell et al., 2012). The greenhouse warming accelerates Brewer–Dobson circulation reducing ozone in the tropical lower stratosphere and enhancing its abundance over middle to high latitudes (Deckert and Dameris, 2008; Zubov et al., 2013). The ozone changes have substantial implications for the climate. The influence of the ozone recovery associated with the implementation of the Montreal Protocol limita- tions on the production of ozone destroying substances on the SH has been identified in observations and model simu- lations (e.g. Son et al., 2008; Robinson and Erickson, 2015). Recently, it was suggested that the use of interactive chem- istry instead of prescribed ozone climatology can influence climate model properties. Dietmüller et al. (2014) showed that the application of interactive chemistry reduces the cli- mate sensitivity by 3–8 %. A similar reduction in the cli- mate sensitivity was also found by Muthers et al. (2014b). A more substantial reduction in the model response to 4 × CO 2
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Heat-Modeling of Microwave Assisted Epoxidation of Palm Acid Oil

Heat-Modeling of Microwave Assisted Epoxidation of Palm Acid Oil

The microwave method of chemical reactions is relatively new as opposed to conventional thermal heating. Due to the fact that microwave heating is a common domestic method used for cooking, the vast majority of studies researching the effects of microwave-irradiation on oil structure and properties have focused on the changes in the lipids of the food itself. Many other studies have exposed seed crops to microwave irradiation prior to any extraction processes, but few studies have focused on the changes in structure and properties of microwave irradiated purified oil. In these studies, pressure and temperature measurements inside the microwave cavity, pose a certain challenge as limited devices can be utilized without interfering or damaging the magnetron or the device itself. More often than not, the control and setting of reaction parameters is limited to the energy input and the irradiation time. Accuracy of the measurements is also in question as the most common method of using radiometry often provides different temperature feedbacks at different depths. While microwave chemistry could well be the most convenient, rapid and energy-saving way to initiate a chemical reaction, these limitations remain unaddressed and until more detailed studies are made and comprehensive findings are more widely found, a comparison with classical reaction conditions is difficult and probably the reason to why speculations about non-thermal (or microwave) effects are a rife. With this in mind, there is need to develop a 3D Finite Element model to better study the energy that the electromagnetic wave (microwave) imparts on the reactants and its effect (Thomas and Dozier, 2010).
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Doping of polyaniline by corona discharge

Doping of polyaniline by corona discharge

conditions, namely corona treatment for positive and negative polarities, air humidity, treatment time, corona current, and the geometry of the corona triode, on the electrical conductivity of the polyaniline is presented. The results indicate that the corona discharge leads to protonic doping of polyaniline similar to that which occurs in conventional protonic acid solution doping. Atomic force microscopic analysis shows that, as the PANI is exposed to the corona discharge, its globular morphology is disrupted leading to the appearance of droplet-like features and a significant decrease in the average height and surface roughness. Doping by corona discharge presents several advantages over the conventional solution method namely that it is a dry process which does not require use of chemicals reagents, and which is both rapid and avoids dopant migration. The latter can be important for applications of PANI in microelectronic devices. © 2000 American Institute of Physics. @S0021-8979~00!01608-X#
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Model of knowledge representation about materials in the form of a relational database for CAPCAST system

Model of knowledge representation about materials in the form of a relational database for CAPCAST system

Checking the dependency of attributes is done to omit the un- necessary attributes, the step which can be of crucial importance in optimising the decision-making process. A smaller number of attributes means less of a dialogue with the user and quicker search of the rule base looking for adequate procedure of reason- ing. In the case of decision tables that contain very large sets of redundant attributes (created during the operations associated with data mining), the possibilities of reduction can become critical elements in building of a knowledge base. A totally different situation occurs when the decision table is created by knowledge engineers in a controlled manner, based on e.g. literature, expert knowledge, and/or standards, when the set of attributes is authori- tatively created basing on the available knowledge about the phenomena. In this case, the reduction of attributes is not neces- sary, as it can be assumed that the number of unnecessary attributes (if any) shall not deteriorate the model classificability.
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The quality of castings obtained during lost-wax and Replicast CS processes in aspect of ecology

The quality of castings obtained during lost-wax and Replicast CS processes in aspect of ecology

Haratym, Dok ł adno ć wymiarowa odlewów wykona- nych w procesie Replicast CS, Archiwum Odlewnictwa rocznik 3, nr 9, Katowice 2003.. Arendarski, Niepewno ć pomiarów, Oficyna Wydaw- nic[r]

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The Concept of Early Vascular Ageing – An Update in 2015

The Concept of Early Vascular Ageing – An Update in 2015

When should EVA be suspected? One approach is to consider a positive family history of early onset of obesity, hypertension, T2D, and CVD, and to screen relatives. Another approach is simply to use clinical skills and look for general signs of early biological ageing (facial appearance, gait, skin turgor, etc.), as was tested in a Danish study of identical twins which found that older-looking twins (as judged by lay people provided with facial photos) displayed a higher risk-factor burden, shorter telomere length, and a worse prognosis during follow-up. 22 A limitation of this study was
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Envelopes of Cometary Orbits

Envelopes of Cometary Orbits

First studies of cometary orbits serve as a his- torical introduction to astrodynamics. Namely, their trajectories are also influenced by non-gravitational forces, for example by the acceleration resulting from ejection of a jet of a material from the comet. Most cometary orbits are very elongated. Many physical quantities related to the very elongated cometary or- bits change by several orders of magnitude. Every cometary orbit which is observed as parabolic actu- ally is elliptical as further calculations usually show. If this is not the case, this is due to the fact that the second focus is too remote to measure it. Therefore, nonstandard analysis could be the appropriate math- ematical tool in the study of cometary trajectories. In the rest of this article we shall use the terminology of nonstandard analysis and the words standard and infinitesimal will have meaning as explained in the previous sections. For example, if the value of the velocity at the perihelion is assumed to be standard, then the velocity at aphelion may be taken as an in- finitesimal. In particular, we shall discuss parabolic paths. By our consideration in the previous section we may assume that every parabolic trajectory is an ellipse. Our discussion is relied on available cometary data, so we shall first shortly review them.
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Selection of the temperature of casting the bronzes to plaster moulds

Selection of the temperature of casting the bronzes to plaster moulds

dependence from the temperature of casting the bronze to the mould on Figure 6. From the introduced cross - section of casts from the probe TDAg, it results that it together with considerably grows up the depth of the contraction cavity with the growth of the temperature of casting, and what joins with this executed along its axis the volumetric contraction grows up, especially bronze B555 (Fig. 5a and 6). The bronze B10 is characterizes considerably smaller volumetric contraction (Fig. 5b and 6), however overheated 1180 °C above and cast to the hot plaster mould, in the conditions of the atmospheric pressure, it undergoes strong gassing with what considerable decrease of the depth of the contraction cavity joins (Fig. 5b 1200 ° C and Fig . 6). Zinc as high active metal in the relation of oxygen influences the lower- ing of the content of gases dissolved in the bronze B555. Consid- erably larger content Zn in the chemical composition of the bronze B555 (approx. 5%), in the comparison with the bronze B10 (to 0.5 %), it favours creation on the surface of the solidifica- tion bronze of the layer of oxides Zn and Cu, in the composition natural slags about the smaller mass density from the liquid bronze, making difficult chemical adsorption and dissolving the hydrogen and oxygen in the liquid bronze. Bronze B10 including first of all the admixture approx. 10% Sn, element of little active in the relation to oxygen, it absorbs from surroundings highly both the hydrogen as and the oxygen, what it brings in the conse- quence, together with the growth of the temperature of casting, to gassing the bronze.
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Determination of the void fraction and drift velocity in a twophase flow with a boiling solar collector

Determination of the void fraction and drift velocity in a twophase flow with a boiling solar collector

Abstract—This paper presents an approach to determine the void fraction and the drift velocity in a two-phase flow with a boiling solar collector using easily obtained experimental data. The solar collector operates in a thermal siphon circuit, where the working fluid absorbs solar radiation mostly while boiling. The vapor bubbles release their latent heat in a condenser, while heating up a flow of water–glycol. Two numerical procedures are developed to calculate the void fraction because its experimental values cannot be easily measured. The use of a flow meter causes an additional pressure drop in the thermal siphon circuit and, consequently, changes the circulated mass flow rate. The first numerical procedure is based on a force balance in the thermal siphon loop and is used to estimate the total mass flow rate and the void fraction in the circuit. The second uses a drift flux correlation to estimate the void fraction and the drift velocity. Both procedures use the experimental values for the vapor mass flow rate, which is determined by an energy balance in the condenser. The volumetric flow rate of the water–glycol mixture and its temperature difference across the condenser are experimentally measured. The pipe length of the two-phase flow in the solar collector is experimentally determined using 44 thermocouples attached to the back of flow channels in the absorber plate. The results show that the two numerical models compare well and that either one can be used to estimate the void fraction in the two-phase flow solar circuit.  2000 Elsevier Science Ltd. All rights reserved.
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