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Because the operationa] space fonnulation for robot dynamics is fairly new, few efficient methods exist fw computing its components. The conceptual framework for the operational space fomulation was presented by Khatib in [17,18,19], where he established a basic definition for the operational space inertia matrix. In [19], Khatib shows that the operational space inertia matrix of a 6 degree-of-freedom manipulator may be computed as follows  [Pg.43]

The relationship in Equation 4.1 was found by examining the quadratic frxms of the manipulatcx kinetic energy matrix in the joint space and operational space dynamic models, th this equation, Khatib shows the explicit dependence of A on the generalized system coordinates, either operational space (x) or joint space (q). [Pg.43]

Khatib also discusses the operational space formulation for redundant manipulators. In this case, the definition for the operational space inertia matrix [Pg.43]

Ar(x) - 6x6 operational space inertia matrix for a redundant manipulator, J(q) = 6y.N Jacobian matrix, [Pg.43]

Rodriguez, Kreutz, and Jain [37, 38] present a linear recursive algorithm for the operational space inertia matrix, referred to as the operational space mass matrix , as part of an original operate formulation for open- and closed-chain multibody dynamics. In general, this operator apfxoach appears to be quite powerful, especially in matrix factorization and inversion, and with it, the authors [Pg.43]

There have been very few method development processes proposed for 2DLC. One study (Schoenmakers et al., 2006) is titled A protocol for designing comprehensive two-dimensional liquid chromatography separation systems. This study advocates that one initially chooses the first-dimension maximum acceptable analysis time, the first-dimension maximum workable pressure drop, and the smallest first-dimension column diameter. The first two variables are then used to construct a Poppe plot (Poppe, 1997)—pronounced Pop-puh (Eksteen, 2007). [Pg.128]

The Poppe plot is a log-log plot of H/uq = t(JN versus the number of plates with different particle sizes and with lines drawn at constant void time, t(). H is the plate height, Vis the number of plates, and u() is the fluid velocity (assumed equal to the void velocity). The quantity H/u() is called the plate time, which is the time for a theoretical plate to develop and is indicative of the speed of the separation, with units of seconds. In the Poppe plot, a number of parameters including the maximum allowable pressure drop, particle diameter, viscosity, flow resistance, and diffusion coefficient are held constant. [Pg.128]

FIGURE 6.1 A Poppe plot for the required plate number in conventional HPLC. The parameters are taken from Poppe s original paper (Poppe, 1997). The parameters are maximum pressure AP = 4x 107 Pa, viscosity / = 0.001 Pa/s, flow resistance factor p = 1000, diffusion coefficient D= lx 1CT9 m2/s, and reduced plate height parameters using Knox s plate height model are A — 1, B— 1.5, C = 0.05. [Pg.129]

Given the construction of the Poppe plot, the number of plates, the column length, the peak capacity, and the particle diameter are determined in the Schoenmakers et al. (2006) scheme all for the first-dimension column. These are then used to determine the second-dimension parameters that include the particle diameter, the number of plates, column length, and peak capacity. Other variables are utilized and optimized from this scheme. [Pg.129]

Another study (Bedani et al., 2006) starts from the multidimensional sampling theory (Murphy et al., 1998a), which is discussed in Chapter 2. This sampling theory states that one needs to sample the first dimension separation system at least three to four times per peak width for maximum resolution. Bedani et al. then equate the second-dimension total analysis time to the first-dimension narrowest peak standard deviation. This defines the second-dimension operational parameters. All other parameters can be derived from this balance and Bedani s study goes through this and discusses how the rest of these variables are obtained. [Pg.129]

Self-excited combustion instabilities are associated with the propagation and reflection of heat-release-induced acoustic waves and their interactions. Hence, flame sound represents the main source of these acoustic waves. Therefore, sound pressure level (SPL) data for turbulent nonpremixed jet flames have been obtained for two Turbulent Nonpremixed Flame (TNF) workshop flames, DLR-A and DLR-B [1]. The exit Reynolds numbers (Re) for the two flames based on injected gas properties at room temperature were 15.200 (DLR-A) and 22,800 (DLR-B). Air was used for studying the sound emission from equivalent nonreacting jets. The flow in each case had very low exit Mach numbers (M = 0.04- [Pg.214]

18) based on the sound speed at room temperature. The A-weighted SPL was calculated based on recorded sound pressure data acquired using a National Instrument Analog-to-Digital Converter (ADC) board and a PC. [Pg.214]

Additional results showing radial variation and Re number dependence allow one to conclude that the combustion noise source is distributed over a wider spatial extent than for the air jet and the difference between reacting and nonreacting SPL decreases with increasing Re number. Further spectral analysis of these results is underway, together with similar measurements in swirling and partially premixed flames and combustors. [Pg.215]

A large number of theoretical ab initio calculations have been performed on benzene (12-38) and mono- and disubstituted benzenes (6,20,39-92). There appear to be no reports to date of ab initio calculations on polysubstituted (i.c. with more than two substituents) benzenes. Brief comment follows on some of the previous studies most closely related to the present work. [Pg.3]

The effect of para substituents on the OH torsional barrier in phenols and nitrogen inversion barrier in anilines has been examined by Pople and co-workers (8,9). These topics are discussed in Sections V.A.4 and V.A.5. The results show that in a para-substituted benzene, a w donor and a tt acceptor interact favorably with one another whereas the situation of two tt donors leads to resonance saturation and a destabilizing interaction. Wepster et al. (93,94) have reached similar conclusions on the basis of experimental studies. The relative stabilities of ortho-, meta-, and para-disubstituted benzenes for the substituents CN, OH, and F have been studied by von Niessen (66) using a Gaussian lobe minimal basis set. Radom has calculated the effect of substituents on the acidities of phenols and noted good agreement with available gas-phase data (65). [Pg.3]

Reynolds and co-workers (61,62,95-100) have used ab initio and other theoretical and nmr chemical shift data to examine substituent effects in substituted benzenes. Systems studied in this way include substituted benzoic acids (61), styrenes (62,98), phenylacetylenes (99), and phenylalkanes (96). Particular emphasis has been placed on the separation of field, inductive, and resonance effects. [Pg.3]

There is also some non-ah initio theoretical and experimental work of direct relevance to the present study. For example, the question of the existence of TT-inductive effects (Id) has been paid considerable attention by a number of [Pg.3]

A key paper on monosubstituted benzenes, which represents the basis of the more recent work reported here, is that by Hehre, Radom, and Pople (6). It contains a detailed analysis at the STO-3G level of substituent ring interactions in monosubstituted benzenes, and encompasses charge distributions, stabilities, and conformations of 35 substrates. Relevant results are more fully detailed in Section IV. [Pg.4]

Author Year Objective of Study Major Findings and Activities [Pg.58]

Briffa and Dumbrowski 1966 To study the machanism of air entrainment into a flat (fan) spray nozzle. The mass of air entrained into the spray, decay of air velocity along the spray axis, and the spread of drops in the plane normal to that of the spray sheet were related to operating conditions by theoretical equations confirmed by the experimental work [Pg.58]

Eggleston, Herrera, and Pish 1976 To provide needed data about the use of air entrained by a water spray to dilute flammable vapor releases below the lower flammability limit. Absorption/adsorption effects are insignificant in the case of ethylene and vinyl chloride. Sprinklers and water-spray nozzles vary widely in their efficiency as air movers. Flame quenching was not affected in any of the experiments Water sprays increased the rate of flame propagation. The air-pumping action of a water curtain can be used to set up a barrier to the horizontal flow of vapors. [Pg.58]

Heskestad, Kung, and Todtenkopf 1976 To study the entrainment of air into water sprays discharging into quiescent surrounding, both theoretically and experimentally Developed a simple theoretical model for air entrainment flow in a water spray discharging downward in quiescent space. Air entrainment flow is sensitive to water discharge rate when nozzle pressure is varied at constant nozzle diameter. Entrainment flow is insensitive to discharge rate when nozzle diameter is varied at constant nozzle pressure. [Pg.58]

Martinsen, Muhlenkamp, and Olson 1977 To test varied spray nozzles and water flow rates to determine their effectiveness in dispersing LNG vapors. Water sprays do affect concentration reduction of LNG vapors [Pg.58]

We finally show in Fig. 4.24 the same three cases as shown in Fig. 4.23 but where the angle of incidence is 67.5° rather than 45°. Again as in Fig. 4.23 we observe a significantly lower scattering level for the loaded case in Fig. 4.24c as compared to the total unloaded case in Fig. 4.24b ( 10dB) but even up to several decibels below the scattering level in the Floquet case, Fig. 4.24a). [Pg.115]

We finally remind the reader that the reduction level is not unique but depends on the size of the array as well as the angle of incidence (see Fig. 4.14 and Fig. 4.13, respectively). [Pg.115]

It is considered courteous and scholarly to present other researchers contributions ahead of your own. However, if your subject is somewhat obscure and perhaps even controversial, this sequence often leads to a clouded relationship between new and old contributions. In fact, reference often end up being merely a litany of titles that must be there in order not to offend anyone. My own experience along those lines has often been that although 1 might have been referenced, it was doubtful whether my contribution was ever read or at least nnderstood. Simply put, the references are simply not meaningful to the reader until after he has read most of the paper. [Pg.115]

in an attempt to alleviate this problem I will review other contributions at this point. Please understand that this sequence in no way is an attempt to put other researchers work in the background. [Pg.115]

Recall that 5 = 1.0 corresponds to the endfire condition, leading to a gain significantly below that of a Yagi-Uda array tuned to maximum gain (it is close to the Hansen-Woodyard condition). [Pg.115]


The time taken to complete a base line study and EIA should not be underestimated. The baseline study describes and inventorises the natural initial flora, fauna, the aquatic life, land and seabed conditions prior to any activity. In seasonal climates, the baseline study may need to cover the whole year. The duration of an EIA depends upon the size and type of area under study, and the previous work done in the area, but may typically take six months. The EIA is often an essential step in project development and should not be omitted from the planning schedule. [Pg.71]

Secondly, the linearized inverse problem is, as well as known, ill-posed because it involves the solution of a Fredholm integral equation of the first kind. The solution must be regularized to yield a stable and physically plausible solution. In this apphcation, the classical smoothness constraint on the solution [8], does not allow to recover the discontinuities of the original object function. In our case, we have considered notches at the smface of the half-space conductive media. So, notche shapes involve abrupt contours. This strong local correlation between pixels in each layer of the half conductive media suggests to represent the contrast function (the object function) by a piecewise continuous function. According to previous works that we have aheady presented [14], we 2584... [Pg.326]

In the same section, we also see that the source of the appropriate analytic behavior of the wave function is outside its defining equation (the Schibdinger equation), and is in general the consequence of either some very basic consideration or of the way that experiments are conducted. The analytic behavior in question can be in the frequency or in the time domain and leads in either case to a Kramers-Kronig type of reciprocal relations. We propose that behind these relations there may be an equation of restriction, but while in the former case (where the variable is the frequency) the equation of resh iction expresses causality (no effect before cause), for the latter case (when the variable is the time), the restriction is in several instances the basic requirement of lower boundedness of energies in (no-relativistic) spectra [39,40]. In a previous work, it has been shown that analyticity plays further roles in these reciprocal relations, in that it ensures that time causality is not violated in the conjugate relations and that (ordinary) gauge invariance is observed [40]. [Pg.97]

A more general classification considers the phase of the total electronic wave function [13]. We have treated the case of cyclic polyenes in detail [28,48,49] and showed that for Hiickel systems the ground state may be considered as the combination of two Kekule structures. If the number of electron pairs in the system is odd, the ground state is the in-phase combination, and the system is aromatic. If the number of electron pairs is even (as in cyclobutadiene, pentalene, etc.), the ground state is the out-of-phase combination, and the system is antiaromatic. These ideas are in line with previous work on specific systems [40,50]. [Pg.342]

The expressions for the rotational energy levels (i.e., also involving the end-over-end rotations, not considered in the previous works) of linear triatomic molecules in doublet and triplet II electronic states that take into account a spin orbit interaction and a vibronic coupling were derived in two milestone studies by Hougen [72,32]. In them, the isomorfic Hamiltonian was inboduced, which has later been widely used in treating linear molecules (see, e.g., [55]). [Pg.510]

The excellent agreement of the results of HCR ab initio studies with the corresponding experimental findings clearly shows that the strongest influence on the numerical accuracy of the vibronic levels have effects outside of the R-T effect, that is, primarly the replacement of the effective bending approaches employed in previous works by a full 3D treatment of the vibrational motions (for an analysis of this matter see, e.g., [17]). Let us note, however, that such a... [Pg.514]

The SAso = 0 limits of the fomiulas presented in this subsection cover all particular cases (including Uj = 1, Oc = l,anduj = 2, Uc = 1) handled in the previous works [18,132,153]. [Pg.538]

Previous work in our group had shown the power of self-organizing neural networks for the projection of high-dimensional datasets into two dimensions while preserving clusters present in the high-dimensional space even after projection [27]. In effect, 2D maps of the high-dimensional data are obtained that can show clusters of similar objects. [Pg.193]

In general the on temperature, pressure and composition but, as in all our previous work, we shall assume that the reaction mixture behaves ideally. Then the depend only on temperature and are simply the molar enthalpies of the separate pure species. It therefore follows that... [Pg.157]

The facilities for experimental work were poor, with inadequate wet laboratory space. In our discussions, I mentioned to Kaprielian my interest in significantly extending my previous work into the area of hydrocarbon chemistry. I felt that by establishing a strong program of basic research and graduate education in hydrocarbon chemistry, USC could become a leader in this important field. Because the memory of the first Arab oil embargo was still fresh, this struck a chord with Kaprielian, who felt that he could sell my research interest to the trustees and establish a Hydrocarbon Research Institute at USC that could accommodate me, as well as other chemistry faculty members whose interests could fit into its framework. [Pg.111]

Thermodynamics is no longer a subject for an extensive amount of research. The reasons for this are two-fold the completeness of existing or previous work... [Pg.9]

The composition of an oxidizing mixture is altered extensively by the passage of a cool flame (66,83,84). Before passage of the flame, oxygenated materials are present. In the case of hexane oxidation, ROO radicals are reportedly displaced by HOO radicals above 563 K (85), in concordance with previous work (86,87). After the passage of a cool flame, olefins, some conjugate and others of lower molecular weight, are observed. [Pg.340]

Would the skilled technician, engineer, or scientist consider the newer invention unexpected or surprising in view of this previous work ... [Pg.33]

Because the ore quaUty is variable, large open-pit mining areas are first identified by general exploration specific mining strips are later identified by further exploration and testing. Surface mining methods are used. The overburden is drilled, blasted, and removed, and the waste from a given strip is dumped into a previously worked-out strip. After removal of the overburden, the exposed caUche is drilled, blasted, and loaded into 80-metric ton tmcks that dehver the ore to a transfer rail station for transportation to the plants. [Pg.194]

More recently, in the middle 1990s, the UK s Health and Safety Executive (HSE) also reviewed the push-pull system. Hollis and Fletcher offer a comprehensive literature review on push-pull ventilation and note that the main conclusions of previous work on push-pull ventilation of tanks are that the control is primarily supplied by the inlet jet, forming a wall jet along the surface of the tank, and that the main purpose of the exhaust hood is to remove the air and contaminant contained within the push jet. [Pg.945]

Craig in a critical revision of previous work. Atisine is a colourless... [Pg.687]

In addition, the numercial simulations were compared with an experiment in which a large heptane aerosol-air cloud was detonated. This exercise may be regarded as a continuation of previous work of Fishbum (1976), reviewed earlier in this section. Fishbum s conclusions may be summarized as follows ... [Pg.108]

This book complements previous work by CCPS in describing how to undertake the design, development, and installation of process safety management systems. [Pg.229]

In continuing their previous work Bougault and Daniel observed that thiosemicarbazones of a-keto acids (51) also undergo a cyclization resulting in 3-thioxo-5-oxo-2,3,4,5-tetrahydro-l,2,4-triazines (52). In contrast with the cyclization of semicarbazones this cyclization... [Pg.206]


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See also in sourсe #XX -- [ Pg.260 ]

See also in sourсe #XX -- [ Pg.430 ]




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A Guide to Previous Work

Brief Review of Previous Work

Evidence From Previous OBS-GMCSC Work

Molecule, design previous work

Previous Modeling Work

Previous Pyrolysis Work

Previous Synthetic Work

Previous Work Clustering

Previous Work on Adsorption

Previous Work on Electrical Switching in Amorphous Silicon

Relation to previous work

Summary of Previous Work

Surface waves previous work

Survey of Previous Work

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