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Essentially, the difficulty in dehydration technology of lignite depends on the energy state of water in lignite. The fundamental understanding of the water occurrence and energy state in lignite as well as its physical-chemical interaction with coal structure is helpful to the upgrading of lignite. In this paper, the water occurrence in lignite and the changes of oxygen-containing functional groups, pore structure, and water holding capacities at different drying temperatures were researched by DSC, NMR, FTIR and BET, respectively. The binding energies (calculated by DFT using model compounds) of different forms of water in lignite were also summarized. The relationships between energy state and occurrence mode of water in lignite as well as dehydration difficulty and structural changes during dewatering were clarified. The Results show that the energy state of water in lignite divided into three levels. The water in free and pore is in the lowest energy level. Its binding force with coal is pretty weak. So this type of water is easily vaporized and re-adsorbed. It is the main in removed moisture. Generally, the temperature removed free water mainly focused on below 100 °C, and the dehydration temperature of pore water mainly focused on 100–200 °C. The water bonded in hydrogen-bond and capillary confinement is in the middle energy level. The dehydration temperature mainly focused on 200–400 °C. The oxygen-containing functional groups of samples change a little and the re-adsorbed property improves a little after dehydrated. The water mainly produced by chemical reaction above 400 °C is in the highest energy level. Though this type of water does not belong to the natural occurrence of water in lignite, the re-adsorbed property improves much, and it plays the key role in stabilizing the dehydrated lignite interface.

In this paper we present a parametric method for the identification of a horizontal positioning system for a billets unloading machine. The input-output models are obtained on the experimental models and on the priori information of the process. The obtained models are represented as second-order underdamped systems. The assessment of the models is made via simulation and a best fit model follows. In order to improve the current process performances, new automatic control structures for the positioning process can be derived using the determined model

During the content uniformity test of a drug product (tablet formulation), an unknown peak was observed in the HPLC chromatograms. Upon further investigation, it was determined that the unknown peak was originated from an external source and, therefore, the drug product is free of this unknown peak. The next step was to identify the structure of this unknown peak in order to determine the source of this contaminant species. In this paper, we wish to present the strategy and the results of the experiments that led to the identification of this unknown peak. LC-PDA/UV and LC-MS(n) analyses were conducted to obtain the UV spectrum, molecular weight and MS(n) fragmentation pathways of the unknown peak. The MS analysis revealed certain structural features of the unknown species and a number of model compounds that contain such features were then examined for their UV absorbance profiles in an attempt to establish the functional group connectivity within the unknown species. A careful examination of these results in conjunction with the determination of the high-resolution molecular weight led to a short list of potential candidates for the unknown species, among which the most likely one was 1,3-diphenylguanidine. The identification of the unknown contaminant was confirmed by spiking experiments using the authentic compound. The potential source of this contaminant was also identified as derived from the safety filler of the pipette bulb used to prepare the sample solutions during the drug analysis.

Machining of highly abrasive carbon fibre reinforced polymer (CFRP) in the aerospace industry requires processes with excellent machining quality, sufficient tool lifetime and short cycle times. To reach these goals a detailed understanding of the physics of cutting and chip formation based on the tool geometry is necessary. This paper presents a fundamental study in milling of unidirectional CFRP focussing on variable process parameters, tool geometries and fibre orientations. A single-edged tool with cemented carbide inserts of variable macro geometry is utilised. The experiments are evaluated by 3D microscopy of the milled edges, detailed tool wear analyses and interpretation of cutting forces. The key conclusions from the experimental results are drawn to reach a better machining quality and increased tool lifetime. The delamination of top layer fibres from the ply below up to a certain distance from the milled edge, which depends on the forces at fibre cutting angle ϕ = 90°, has been identified as main quality issue. Force and tool wear models based on the measurement data are presented.

The behavior of aggregate demands in an economy is affected by how the distribution of income moves over time. Consider any economy of agents who don't suffer from money illusion, so agents' demand equations are homogeneous in income and prices. This paper describes a property of income distribution movements, called ‘mean scaling’, which is sufficient (and in a weak sense necessary) to make aggregate demands in the economy homogeneous. Mean scaling essentially requires that changes over time in standard income inequality measures (e.g., the coefficient of variation) be independent of changes in mean income over time. An implication is that aggregate demands will not be homogeneous if income redistribution policies are tied to absolute measures of income.

From the point of view of a data warehouse system, collecting and receiving information from source systems is crucial for all subsequent business intelligence applications. Incoming information can generally be classified into two types: (1) the state-oriented data and (2) event-oriented data or transactional data, which contains information about the change performed by processes on the instances of information objects. On the way towards achieving the goal of a full-fledged active data warehouse it becomes more and more important to provide data with minimal latency. In this paper we focus on dimensional data which is provided by general data warehouse applications. The information transfer is performed via messages containing the change of information on the dimension instances. The proposed approach is able to validate the event-messages, reconstruct the complete history of the dimension and provide a well applicable ''comprehensive slowly changing dimension'' (cSCD) interface for queries on the historical and current state of the dimension. A description of the prototype implementation for this kind of an ''active integration'' in a data warehouse and a case study at T-Mobile conclude the paper.

A novel uncertainty assessment methodology, based on a statistical non-parametric approach, is presented in this paper. It achieves quantification of code physical model uncertainty by making use of model performance information obtained from studies of appropriate separate-effect tests. Uncertainties are quantified in the form of estimated probability density functions (pdfs), calculated with a newly developed non-parametric estimator. The new estimator objectively predicts the probability distribution of the models error (its uncertainty) from databases reflecting the models accuracy on the basis of available experiments. The methodology is completed by applying a novel multi-dimensional clustering technique based on the comparison of model error samples with the Kruskall-Wallis test. This takes into account the fact that a models uncertainty depends on system conditions, since a best estimate code can give predictions for which the accuracy is affected by the regions of the physical space in which the experiments occur. The final result is an objective, rigorous and accurate manner of assigning uncertainty to coded models, i.e. the input information needed by code uncertainty propagation methodologies used for assessing the accuracy of best estimate codes in nuclear systems analysis. The new methodology has been applied to the quantification of the uncertainty in the RETRAN-3D void model and then used in the analysis of an independent separate-effect experiment. This has clearly demonstrated the basic feasibility of the approach, as well as its advantages in yielding narrower uncertainty bands in quantifying the codes accuracy for void fraction predictions.[All rights reserved Elsevier].

In this paper, we characterize the class of all spaces X whose products with a fixed non-Archimedan space Y are normal. In particular, we give a characterization of all spaces X whose products with every ω μ -metrizable space are normal.

A potential new process to styrene monomer from n-butane consists of oxidation of n-butane to butadiene followed by dimerization of butadiene to 4-vinylcyclohexene (VCH) and oxydehydrogenation of VCH to styrene. In this paper we report a catalyst which provides 40%–50% conversion of n-butane at 80% selectivity to butadiene and the n-butenes when exposed to 5–10 s pulses of n-butane followed by air regeneration. The optimum catalyst consists of 15%–25% MoO 3 dispersed on MgO. The addition of small amounts of alkali metal compounds are used to minimize the production of carbon oxides. Characterization of these catalysts by laser Raman spectroscopy and XANES indicates that octahedral polymolybdates and micro crystals of MgMoO 4 are initially the major species at molybdenum loadings corresponding to maximum activity on fresh catalyst. Designed experiments have resulted in models predicting the relationship of selectivity and conversion for various process conditions.

This paper examines changes residential rooftop solar customers make to their demand and energy usage when they take service on a demand rate, and the impact those changes have on their bills and the utilities' cost of service.

In the current decade, modeling credit risk is increasingly gaining attention by risk managers of banks and researchers. Among the available credit risk models, Merton's equity-based approach is considered as a pioneering tool for measuring default risks. From the day it was developed by Robert Merton, it is being regarded as one of the primary model of assessing credit risk. In this model the default process is endogenous, and relates to the capital structure of the firm. The model presumes that the only source of uncertainty in equity prices is the uncertainty in the firm's net asset value. Therefore, the only risk considered is the firm specific risk. Ironically, the above market condition holds only when the market is efficient. The model developed in the present paper is virtually a modification of Merton's model. However, it is not subject to the limitation of that model. Therefore, the modified model will necessarily widen the scope of equity-based modeling ranging from a strict efficient market to an inefficient market.

Effective wildlife management needs historical data on herbivore abundance and its interactions with vegetation, climate and disturbance over longer time periods that is available through observational and archive data. Spores specific to herbivore dung provide a potential source of information on past herbivore abundances. This paper sets out to evaluate the potential of fungal spores as environmental indicators and in particular the use of coprophilous fungi in understanding past herbivore densities and their impact on the savanna landscape of Kruger and Limpopo National Parks (South Africa and Mozambique). Spore assemblages from six sedimentary cores are analysed and compared with the pollen data. Spores of coprophilous fungi, Coniochaeta cf ligniaria, and Sordariaceae in particular provide a valuable source of information about past herbivore densities. The spore assemblages of investigated localities show historical fluctuations in herbivore abundance. Peaks in wild/domestic herbivore densities can be seen, on a local scale from 800 to 900 AD and another at 1400 AD, however, these cannot be linked with any significant changes in vegetation. The last 200–300 years have seen an increased abundance of herbivores in the Limpopo floodplain sites, particularly domestic cattle. There is no clear correspondence between changes in herbivore abundance and local vegetation in this period or the 20th century. However, domestic cattle, together with wild herbivores, probably contributed to creating a mosaic type of landscape with heterogeneous tree cover.

We examine the equity premium puzzle with the perspective of the theory of Rational Beliefs Equilibrium (RBE) and show that from the perspective of this theory there is no puzzle. In an RBE agents need to be compensated for the endogenously propagated price uncertainty which is not permitted under rational expectations. It is then argued that endogenous uncertainty is the predominant uncertainty of asset returns and its presence provides a natural explanation of the observed premium. Utilizing data on the asset allocation of 63 U.S. mutual funds, we test some empirical implications of the theory of rational beliefs as well as estimate the parameters of risk aversion of mutual fund managers. Our tests show that the predictions of the theory are consistent with the empirical evidence. We then construct a simple two agent model of the U.S. economy in which the agents hold rational beliefs and calibrate it to the empirical experience in accord with the parameters of the Mehra and Prescott (1985) paper. The results of our calculations show that for a large set of parameter values the model predictions fit closely the historical record.

On what grounds does the law punish attempted offenses? The dominant answer is that the law punishes attempts to commit an offense precisely because they are attempts (extra-legally), and it is true as a general moral principle that if one should not X, one should not attempt to X. If this is right, then the proper contours of the law of attempts should track the contours of what are attempts (extra-legally). At least to a first approximation, that is, law should track metaphysics. Call this the “Attempt Theory” of attempt liability. Gideon Yaffe’s recent book, "Attempts," is a rigorous and philosophically sophisticated critical analysis of attempt law predicated on just this foundational assumption — the assumption, to repeat, that attempts to commit an offense should be criminalized because they are attempts as a pre-legal or extra-legal matter. However, there is another possible answer to the question. Possibly, those things that are in fact attempts are properly criminalized not because they are attempts, but because the best reasons for criminalizing the complete or “perfect” offense are also good reasons to criminalize this conduct, and there are no compelling reasons, of policy or justice, not to. We can call this the “Underlying Reasons Theory” of attempt liability. The Underlying Reasons Theory does recognize that there are things in the world that are attempts and that one who attempts to do what the criminal law forbids should be punished. It just maintains that the fact that an actor attempted to commit an offense is not, strictly speaking, what justifies our punishing her. This short review of Yaffe’s book explicates the difference between the Attempt Theory and the Underlying Reasons Theory as approaches to criminal liability for what we presently call “attempts.” In a nutshell: paradigmatic attempts would be criminalized on both accounts, but the Underlying Reasons Theory is likely to endorse criminalization of some conduct that the Attempts Theory would not. This paper advocates the Underlying Reasons Theory and argues that we can and should assess the proper scope of “attempt law” without working through the metaphysics of attempts.

Economic theorizations of political bias and war as laid out in Bargaining Theory (Jackson and Morelli 2007; Anderton and Carter 2009) have demonstrated that a political leadership’s penchant for war may be much higher than that of the people they represent, and the calculus of war for internal political gains can spur them on to inter-state violence. To put this assertion to the test, this working paper examines the BJP under Narendra Modi as instigator of the Pulwama War and the India-Pakistan standoff of 2019. The findings of the working paper indicate that the BJP government’s expediency of war conforms to, and resonates with, the bargaining theory of political bias and war, as theorized in the game-theoretic economic literature.

The combination of Java applications as graphical user interfaces and the Matlab-Simulink environment as the simulation engine seems to be a good solution for taking a particular control lab to distant students. In this paper, it is presented a new kind of simulation environment for qualitative teaching on concepts of Control Engineering by means of a suitable configuration of experiments by the tutor or teacher.

The paper systematically studies the impact of the 3d transition metals Ti, V, Cr, Mn, Fe, Ni and Cu on electrochemical stability of non-passivated cobalt-base alloys {0 0 0 1} surface by evaluating the chemical potential and the electrode potential shift relative to pure cobalt metal using density functional theory calculations. Cr, Fe, Mn, and V are found to make the Co atoms more stable on the {0 0 0 1} surfaces of the corresponding alloys compared to pure Co {0 0 0 1} surfaces, whereas Ti, Ni, and Cu make Co atoms much less stable. Among all the considered alloying elements, chrome is the most beneficial to the stability enhancement of alloys. Furthermore, the effects of water and hydroxyl adsorption on the electrochemical stability are considered. It is found that the surface adsorption properties may be considerably modified by introducing the Cr atoms. Our results indicate that water or hydroxyl adsorption destabilizes both the Co–Cr alloy and pure Co surface. However, the Co–Cr alloy surface is still more stable than the pure Co surface in the presence of adsorbed water, while the pure Co surface is more stable than the Co–Cr alloy surface in the presence of adsorbed hydroxyl. Our calculation reveals that the electrochemical corrosion property of the Co–Cr alloy is insensitive to water adsorption and sensitive to hydroxyl adsorption in comparison with the pure Co metal.

The study analyzed 2013 bilateral trade data between Malawi and each of the following three trading partners; Mozambique, South Africa and China. Using data from the World Integrated Trade Solution (WITS), the study employed a simple Ordinary Least Squares (OLS) model to estimate the impacts of tax rates on tariff evasion and conducted some robustness checks. We found that tax rates applicable to Mozambique and South African Imports reduce the evasion gap. This is interpreted to mean that other countries' exports to Malawi are declared as originating from Mozambique and South Africa in order to enjoy the preferential rates of duty due to the bilateral trade agreements that exist between each of the two countries and Malawi. We also found out that tax rates have a positive significant effect on tax evasion of Chinese imports. Consequently, the paper established that higher tax rates induced tax evasion.

Searching for information about a specific person is a frequent online activity. In most cases, users are aided in the search process by queries containing a name in Web search engines. Typically, Web search engines provide just a few accurate results associated with a name-containing query. Most existing solutions for suggesting synonyms in online search are based on pattern matching and phonetic encoding, however very often, the performance of such solutions is less than optimal. In this paper, we propose SpokenName2Vec, a novel and generic algorithm which addresses the synonym suggestion problem by utilizing automated speech generation, and deep learning to produce novel spoken name embeddings. These embeddings capture the way people pronounce names in a particular language and accent. Utilizing a name’s pronunciation can help detect names that sound alike, but are written differently. We demonstrated the proposed approach on a large-scale dataset with more than 250,000 forenames and surnames and evaluated it on two ground truth datasets containing 7400 forenames and 25,000 surnames (including their verified synonyms). The performance of SpokenName2Vec was found superior to the 10 other algorithms evaluated, including phonetic encoding, string similarity, and machine learning algorithms. The results obtained emphasize the potential of spoken name embeddings for improved synonym suggestion.

The application of the indentation method to measure the elastic modulus of particles embedded in a composite is theoretically investigated in this paper by finite element simulation. The Oliver–Pharr method, which is widely used in commercial nanoindentation instruments, is used to probe the elastic modulus of the particle from the simulated indentation curve. The predicted elastic modulus is then compared with the inputted value. Two cases are studied, that of a stiff particle embedded in a soft matrix and a soft particle embedded in a stiff matrix. In both of these cases, there exists a particle-dominated depth. If the indentation depth lies within this particle-dominated depth, the Oliver–Pharr method is able to be applied to measure the particle’s elastic modulus with sufficient accuracy if the real contact area is used. This could lead to an experimentally-convenient method of determining the primary properties of individual particle, providing they can be well dispersed in the polymeric matrix.

This paper analyses entry deterrence and accommodation by low cost carriers (LCCs) with two games. In the first game two LCCs compete in a horizontal differentiation setting. Results show that the entrant may drive away the incumbent from its original location under certain conditions. In the second game the incumbent is a LCC and the entrant a full service carrier, with vertical differentiation. The incumbent tries to deter or accommodate entry by product proliferation. We find out that the incumbent will only deter entry if it can surpass the entrant’s quality, and that product proliferation is not an accommodating strategy.

Organizations have gone through many changes. They have reinvented themselves to meet the changing needs of their customers, the external influences and the cost pressures over which they have limited control. With the changes required, as a result of the housing transfer, there is an opportunity to refresh and invigorate what they are about as an organization. To work towards aspiration goals that will make us proud of what we achieve. This effort sets out an approach on how organization can continue improvement journey in ‘Shaping up for Excellence’. It can be argued that the fine words in this paper, by themselves, do not improve anything. The key to change is in the culture of the organization; how they deliver the services to their customers and the improvements that will come through ensuring the skills, experience, motivation and the tools to deliver an excellent service are developed and available. The purpose of this document is to set a corporate framework and improvement plan for how we can ‘shape up’ collectively and achieve our goal of excellence in all aspects of our approach and delivery.

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The first part of this paper is occupied by a rapid review of the labours of mechanicians on the subject of friction, from the period of those of Amontons at the end of the 17th century, to those of Coulomb and of Vince in the years 1779 and 1784; from which the author draws the conclusion that the progress of knowledge in this department of science has been slow and unsatisfactory, and that a wide field is still left open to experimental investigation. With a view to elucidate several points not yet sufficiently ascertained by former writers, the author instituted several sets of experiments; some calculated to determine the forces required for dragging bodies of various kinds along a horizontal surface, and others for measuring the angle at which a plane was required to be inclined to the horizon in order to admit of the body sliding down it, attention being paid to the circumstances of pressure, extent of surface, time of previous contact, and velocity of motion. The following are the principal conclusions which the author deduces from his experiments. The friction of ice rubbing upon ice diminishes with an increase of weight; but without observing any regular law of increase. When dry leather is made to move along a plate of cast iron, the resistance is but little influenced by the extent of surface. With fibrous substances, such as cloth, the friction diminishes by an increase of pressure, but is greatly increased by the surfaces remaining for a certain time in contact; it is greater, cœteris paribus , with fine, than with coarse cloths; the resistance is also much increased by an increase of surface. With regard to the friction of different woods against each other, great diversity and irregularity prevail in the results obtained; in general the soft woods give more resistance than the hard woods: thus, yellow deal affords the greatest, and red teak the least friction. The friction of different metals also varies principally according to their respective hardness; the soft metals producing greater friction under similar circumstances than those which are hard. Within the limits of abrasion, however, the amount of friction is nearly the same in all the metals, and may in general be estimated at one sixth of the pressure. The power which unguents have in diminishing friction, varies according to the kind of the fluidity of the particular unguent employed, and to the pressure applied.

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Introduction Common peroneal nerve injury is the most frequent nerve deficit affecting the lower limbs. This leads to foot drop and a so-called steppage gait. Primary surgical nerve repair has an unfavorable outcome in some series. One alternative is posterior tibialis tendon transfer, a procedure designed to achieve active dorsiflexion. The aim of this paper is to report the results we have obtained with this surgery. Methods Between January 2008 and June 2016, a total of 38 patients underwent posterior tibialis tendon transfer, but only those 29 who had a minimum 12-months follow-up were included in analysis. A subcutaneous approach was used for the transfer, with tendon-to-tendon suturing employed, using the tibialis anterior, extensor hallucis longus, extensor digitorum longus and peroneal tendons as targets. The Stanmore Scale was used to rate outcomes. Results Final results were excellent in 15 patients (52%), good in seven (24%), fair in three (10%) and poor in four (14%). Conclusions This tendon transfer procedure has a high success rate, both in our series and in the literature. Considering the poor results observed in primary nerve repair in some patients, we believe that posterior tibialis tendon transfer should be considered for the treatment of foot drop in selected patients.

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A non-Darcy flow develops in porous media when the velocity of reservoir fluids becomes extremely high because of the continuous narrowing of the cross section area of the flow and the convergence of flow streamlines. Therefore, the inertial effect increases significantly and the total pressure drop, required by fluids to move from the outer drainage area towards the wellbore increases significantly due to the extra pressure drop caused by the non-Darcy flow. The extra pressure drop is described by the Forchheimer equation in which the deviation from Darcy's law is proportional to the inertial factor which in turn is a function of porous media characteristics such as permeability and porosity. This paper introduces a new technique for estimating rate dependent skin factors ( DQ sc ) and non-Darcy flow coefficients ( D ). The new technique uses dimensionless pressure for steady state flow to determine these two parameters. A set of plots has been developed for the term ( DQ sc ) based on reservoir configurations i.e. reservoir boundaries (2 x e & 2 y e ), wellbore length, and anisotropy. All the plots have been developed based on the fact that the rate dependent skin factor represents the difference between the total pressure drop and the pressure drop caused by Darcy flow only when non-Darcy coefficient equals to zero. Dimensionless pressure drops for horizontal wells producing from finite acting reservoirs have been calculated for steady state flow when the impact of dimensionless time can be eliminated. The calculated pressure drops have been used in reservoir performance models to estimate rate dependent skin factors and non-Darcy coefficients. A point of special interest in this study is the ability to estimate these two parameters without the need for experimental work or the need to use currently proposed empirical models for calculating them. This new technique requires knowing reservoir configurations (reservoir width and length), the length of the wellbore, and the height of the formation in addition to the anisotropy. The study indicates that rate dependent skin factors and non-Darcy coefficients have the minimum values when the reservoirs having square-shape drainage area. It has also been found that both parameters have great impact on wells with short wellbore length. Additionally, isotropic formations and symmetrical wells perform better than anisotropic formations and asymmetrical wells in terms of extra pressure drop caused by non-Darcy flow.