Performance issues

The improved electrostatic description MTPs provide comes at a cost performance. As mentioned in Section 7.2.1, the number of 

Reduce the number of MTP coefficients on each site In Section 7.2.2, we argued in favor of aligning reference-axis systems along symmetries of an atom s immediate environment, which leads to a number of MTP coefficients to being zero. By computing energies and forces/torques in the MTP sites local axis systems, these null coefficients cancel all interactions in which they participate. Given 

Minimize real-space evaluation in Ewald summation Sagui et al. have quantified the impact of the real-space cutoff used in their MTP Ewald implementation on the energy drift of a constant-energy simulation [54]. Restricting the real-space evaluation to a minimal amount and performing the rest in reciprocal space can lead to significant improvements. The authors showed minimal energy and force errors down to 4.25 A of direct interaction cutoff. They report an increase in computational time due to MTP interactions of only 8.5 with respect to simple PCs. 

In general, improving performance will come at the cost of accuracy. The benefit of using a given trick to reduce computational time lies thus in the eye of the beholder—and the system of interest. 

Utility power distribution is intended to be a constant frequency (e.g., 60 Hz in North America), sinusoidal voltage source. Harmonic content is considered an undesirable distortion. The square-wave output of the simple converter illustrated in Fig. 10.5 would contain all of the odd harmonics, but the amplitude of each harmonic decreases as the harmonic number increases. The harmonic content of the 

Another approach to achieving good sinusoidal waveforms from d.c. storage is to use PWM, a simulation technique that varies the on-time of the power switches to simulate the sinusoid waveform. This simulation method requires additional switching, which increases switching-related losses but can also reduce harmonic distortion. 

Most BESS applications require four-quadrant operation, i.e., the ability of the 

---

Organization Level Principle Process Focus Basic Team Structure Performance Issue Focus Typical Quality System Focus Ideal Quality System Focus... 

Incentive measures are generally used to draw attention to PSM and ESH performance issues that are, to some extent, controlled by worker behavior or management attention. These measures are frequently used for distributing incentive awards or at-risk pay when particular targets are met, for example 1 million hours without an injury or a target number of changes processed correctly. Whether your company uses incentive measures and awards is a matter of corporate practice. 

Held, G. (1999). Enhancing LAN Performance Issues and Answers, 3rd ed. New York John Wiley Sons. 

As noted before, short focal ratios imply severe difficulties in generating the aspherical departure from an ideal sphere. It is, however, directly related to the telescope length, hence to the structure and building sizes, which are major cost positions and performance issues in a telescope project -cost of large structures and buildings, improbable thermal equilibrium hence local turbulence, misalignments and flexures, etc. 

Close tracking of data entry means that performance measures can be tracked and managed. Such measures typically include query rates (which can be tracked by site, investigator, quesiton, and any comparators), time to respond to queries, rate of query rejection, and the like, and they provide an opportunity to identify and correct performance issues, whether associated with an individual site or study or a program. This capability alone provides a powerful tool by which sites throughout the world can be closely monitored. 

Stage 3 Mild cognitive decline Friends, family, and coworkers begin to notice deficiencies problems with names or words become evident performance issues become evident retention of reading material declines losing valuable objects decline in planning and organizational abilities. 

Managing Scale and Scope of Large-Scale Process Operations discusses the performance issues associated with data analysis and interpretation that occur as the scale of the problem increases (such as in complex process operations). 

Once generated, these noise spikes cannot only appear on the input/output rails (causing related performance issues), but also infiltrate the IC control sections, causing it to behave anomalously, and unpredictably. We could even end up briefly losing the usual current limiting function too, leading to disastrous consequences. 

Incidentally, Schottky diodes do not have any reverse recovery current issues, but they do have some body capacitance, which can produce similar effects. However, that fear has always proven to be exaggerated. I have personally not seen any application having a performance issue explicitly related to a bad Schottky. The only exception was a case where the leakage current of the Schottky was so high, it was prematurely tripping the current comparators inside the switcher IC. And there was also a reliability issue once, concerning the dV/df rating of a commercial Schottky. Both these issues are discussed elsewhere in this book. 

The book focuses on three main themes catalyst preparation and activation, reaction mechanism, and process-related topics. A panel of expert contributors discusses synthesis of catalysts, carbon nanomaterials, nitric oxide calcinations, the influence of carbon, catalytic performance issues, chelating agents, and Cu and alkali promoters. They also explore Co/silica catalysts, thermodynamic control, the Two Alpha model, co-feeding experiments, internal diffusion limitations. Fe-LTFT selectivity, and the effect of co-fed water. Lastly, the book examines cross-flow filtration, kinetic studies, reduction of CO emissions, syncrude, and low-temperature water-gas shift. 

Chemical Market Reporter 262, No. 3, 22nd July 2002, p.7 POLYURETHANE INDUSTRY GEARS UP TO TACKLE EMERGING REGULATORY AND PERFORMANCE ISSUES Hoffman J... 

Fig. 6.4 Scheme illustrating how the chemical interactions result in cathode performance issues. 

If all responses to these tests are linear and typical, and all other independent variables remain within normal operating specifications, it can be assumed that the membrane and electrolyser interactions are optimised for operation within the current density range tested in Section 6.3.1. This procedure has been used successfully to diagnose and optimise operating conditions for both standard and high current density operations where unexpected performance issues have arisen. Furthermore, operators... 

P. Persson, Nitromethane safety and performance issues . Report for US Army AMCCOM contract no. DAAL 03-86-D-0001, New Mexico Institute of Mining and Technology, 23 April 1989. 

However, spectroscopic techniques, although nondestructive, do not provide the spatial information that can be critical in solving performance issues, or in developing true product and process understanding. Only techniques that combine both spatial and chemical identification information provide a complete set of tools to determine both product and process understanding. 

Studies indicate that the vast majority of incidents involve human performance issues. Incident investigations should not simply identify human performance as a cause the management system failure that did not prevent or compensate for the potential human performance must he identified and corrected in order to prevent recurrence. An incident investigation management system should provide the tools to identify and address applicable human factors issues. It is important to recognize that human performance problems can occur in all management system areas—not simply to the human operator or maintenance worker closest to the scene. 

Detecting explosives in complex environments requires very sensitive and specific analyzers. Though MS offers excellent detection limits and resolutions (e.g., sensitivity and specificity), general-purpose laboratory instrumentation is not ideally suited for detecting trace levels of explosives in the presence of large abundances of potential interferent compounds. Furthermore MS has traditionally required a skilled operator not only to acquire data but to interpret it. MS developments have tended to focus on the performance issues and less so on the operational issues. 

This chapter addresses the relative cost of molecular mechanics and quantum chemical models for energy and equilibrium geometry calculations as well as for frequency evaluations. Taken together with performance issues addressed in previous chapters, this allows broad recommendations to be made regarding selection of an appropriate model. 

SGPV is an emerging technology. Design, operational, and performance issues remain currently untested. The vendor is currently planning a commercial facihty. 

Poiymers which are 100% acrylic are known for their outstanding exterior durability properties, as well as excellent alkali resistance and overall high performance. Styrene is generally lower-cost than many other monomers, so styrene-acrylics are lower in cost than all acrylics but have poorer exterior durability because styrene is a UV absorber and degrades. Styrene-acrylics, do, however, generally have very good water-resistance properties due to their hydrophobicity. Styrene acrylics are popular in some areas of Europe, Asia, and Latin America. Vinyl acetate is also somewhat lower in cost, so these polymers are popular for interior paints, particularly in the United States, where exterior durability and alkali resistance are not performance issues. 

Performance issues. The performance of MEGALib is largely dependent on the computational cost of the objectives used for the fitness assessment of the population. Certain objectives, such as those based on docking, require substantial execution time while others, such as those based on chemical structure or comparisons to known ligands, are less costly. 

Although supplier engineering contracts are usually fulfilled on satisfactory completion of the SAT, the performance of a computer system over a spread of data-handling conditions in the real-time environment of a manufacturing process is difficult to fully test at any one time. Consequently, consideration should be given to extending contractual conditions related to system performance into the system operational period, where the broader system performance issues can be better evaluated and reported. 

The materials listed in Table 5.1 are also not complete but the selection represents the most relevant composites which are of commercial interest. In addition to the performance issue, there is a strong tendency in research and development to reduce the costs. For that reason, a lot of research is devoted to the niobates as possible replacement for the tantalates, because niobium is cheaper than tantalum. In addition, compensated materials with very high values of the permittivity are currently under development. Recently, for the compound Ag(Nbi a Taa )03 with 0.35< x <0.65, er values of 450 were achieved for potential use as filters (to replace the surface-acoustic-wave devices) and planar antennas in mobile phones [19],... 

Having obtained a trajectory as in Figure 4, it is possible to apply two virtual surfaces within the bed, for example, at heights of one quarter and three quarters of the settled bed height, and to record the times of crossing these surfaces. This enables cycle durations and frequencies to be obtained, which can be useful in diagnosing performance issues. 

---