CAS Model Research Articles

Evolution of Chemical Composition and Modeling of Growth Nonmetallic Inclusions in Steel Containing Yttrium.

The programs WYK_Stal and Bi-Growth, developed at AGH-UST, Kraków, Poland, were used for simulating the refining process, the formation of non-metallic inclusions, and their growth. The Fe-Y-Al-O-S-Ca system in pre-oxidized steel was analyzed, where yttrium formed precipitates from both O and S. When first Al and second Y were added to steel, the proportion of Al2O3 inclusions remained constant. This resulted in higher yttrium losses for oxide formation, whereas the sulfur content promoted sulfide phase formation. The introduction of yttrium at the end of refining contributed to reducing the consumption of this element in the non-metallic phase formation. The addition of aluminum and then calcium were sufficient to achieve a high degree of deoxidation and desulfurization. Calculations performed with WYK_Stal for both (a) and (c) versions of the model showed that the sulfide phase was constituted by CaS and FeS (model c) and CaS (model (a)). The participation of the calcium sulfide phase turned out to be dominant in the inclusions. Their presence was also identified in the slag phase. Simulations of the growth of complex oxide and oxo-sulfide inclusions using the Bi_Growth program showed that the yttrium content of the steel has a decisive role in the formation of complex oxide inclusions and the final oxygen content of the steel. In contrast, for the growth of oxide-sulfide inclusions, the character of growth is determined by the sulfur content of steel.

A reduced-order model for turbulent reactive sprays in compression ignition engines

In this work, we present a reduced-order model for transient turbulent reactive sprays in compression ignition engines. The model is an extension of the previously developed cross-sectionally averaged spray model (CAS) (Deshmukh et al., 2021). A transient turbulence model is derived for the gas phase that allows to model the transient scalar dissipation rate, which is a key parameter in non-premixed combustion. Representative chemistry is solved in mixture fraction space interactively with the flow. The turbulent CAS model combined with the combustion model is termed the cross-sectionally averaged reactive turbulent spray (CARTS) model and can represent unsteady non-premixed combustion behavior. The CARTS model is validated against experimental data as well as three-dimensional (3D) numerical simulations. The model is able to reasonably predict the trends of ignition delay time, flame lift-off length, and soot emissions. The computational cost of the CARTS model is orders of magnitude lower than the 3D simulation methods. This low computational cost enables various applications, including but not limited to the rapid screening of novel fuel candidates as well as off-line training of models to be eventually used in closed-loop control.

A simple and easily implemented risk model to predict 1-year ischemic stroke and systemic embolism in Chinese patients with atrial fibrillation.

Background:Accurate prediction of ischemic stroke is required for deciding anticoagulation use in patients with atrial fibrillation (AF). Even though only 6% to 8% of AF patients die from stroke, about 90% are indicated for anticoagulants according to the current AF management guidelines. Therefore, we aimed to develop an accurate and easy-to-use new risk model for 1-year thromboembolic events (TEs) in Chinese AF patients.Methods:From the prospective China Atrial Fibrillation Registry cohort study, we identified 6601 AF patients who were not treated with anticoagulation or ablation at baseline. We selected the most important variables by the extreme gradient boosting (XGBoost) algorithm and developed a simplified risk model for predicting 1-year TEs. The novel risk score was internally validated using bootstrapping with 1000 replicates and compared with the CHA2DS2-VA score (excluding female sex from the CHA2DS2-VASc score).Results:Up to the follow-up of 1 year, 163 TEs (ischemic stroke or systemic embolism) occurred. Using the XGBoost algorithm, we selected the three most important variables (congestive heart failure or left ventricular dysfunction, age, and prior stroke, abbreviated as CAS model) to predict 1-year TE risk. We trained a multivariate Cox regression model and assigned point scores proportional to model coefficients. The CAS scheme classified 30.8% (2033/6601) of the patients as low risk for TE (CAS score = 0), with a corresponding 1-year TE risk of 0.81% (95% confidence interval [CI]: 0.41%–1.19%). In our cohort, the C-statistic of CAS model was 0.69 (95% CI: 0.65–0.73), higher than that of CHA2DS2-VA score (0.66, 95% CI: 0.62–0.70, Z = 2.01, P = 0.045). The overall net reclassification improvement from CHA2DS2-VA categories (low = 0/high ≥1) to CAS categories (low = 0/high ≥1) was 12.2% (95% CI: 8.7%–15.7%).Conclusion:In Chinese AF patients, a novel and simple CAS risk model better predicted 1-year TEs than the widely-used CHA2DS2-VA risk score and identified a large proportion of patients with low risk of TEs, which could potentially improve anticoagulation decision-making.Trial Registration:www.chictr.org.cn (Unique identifier No. ChiCTR-OCH-13003729).

Long non-coding RNA SNHG16 contributes to progression of carotid atherosclerosis by regulating miR-30c-5p/ADAM10 axis

IntroductionCarotid atherosclerosis (CAS) is one of the main causes of cerebral infarction in the ageing population. Long non-coding RNA small nucleolar RNA host gene 16 (lnc-SNHG16) could promote the development of atherosclerosis. However, the mechanism of lnc-SNHG16 in CAS remains vague.Material and methodsThe expression levels of lnc-SNHG16, microRNA-30c-5p (miR-30c-5p) and disintegrin and metalloproteinase 10 (ADAM10) were detected by real-time quantitative polymerase chain reaction (RT-qPCR). Cell viability and migration were detected by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) and transwell assays, severally. The levels of interleukin-6 (IL-6), IL-β and tumor necrosis factor-α (TNF-α) were assessed by enzyme-linked immunosorbent assay (ELISA). Protein levels of spinal muscular atrophy (SMA), calponin and ADAM10 were examined by western blot assay. The binding relationship between miR-30c-5p and lnc-SNHG16 or ADAM10 was predicted by Starbase, then verified by the dual-luciferase reporter assay.ResultsLnc-SNHG16 and ADAM10 were increased, and miR-30c-5p was decreased in CAS patient and oxidized low-density lipoprotein (ox-LDL)-treated human aortic smooth muscle cells (hASMCs). Lnc-SNHG16 silencing repressed cell viability, migration, inflammation, facilitated differentiation in ox-LDL-treated hASMCs. Moreover, mechanical analysis proved that lnc-SNHG16 improved ADAM10 expression by sponging miR-30c-5p.ConclusionsOur data indicated that lnc-SNHG16 could regulate the progression of ox-LDL induced CAS model by the miR-30c-5p/ADAM10 axis, implying a potential therapeutic strategy for CAS

Quantifying the biophysical effects of forests on local air temperature using a novel three-layered land surface energy balance model

The well-documented energy balance dynamics within forest ecosystems are poorly implemented in studies of the biophysical effects of forests. This results in limitations to the accurate quantification of forest cooling/warming on local air temperature. Taking into consideration the forest air space, this study proposes a three-layered (canopy, forest air space and soil [CAS]) land surface energy balance model to simulate air temperature within forest spaces (Taf) and subsequently to evaluate its biophysical effects on forest cooling/warming, i.e., the air temperature gradient (∆Ta) between the Taf and air temperature of open spaces (Tao) (∆Ta = Taf − Tao). We test the model using field data for 23 sites across 10 cities worldwide; the model shows satisfactory performance with the test data. High-latitude forests show greater seasonal dynamics of ∆Ta, generating considerable cooling of local air temperatures in warm seasons but minimal cooling or even warming effects during cool seasons, while low-latitude tropical forests always exert cooling effects with less interannual variability. The interannual dynamics of ∆Ta are significantly related to the seasonality of solar geometry and canopy leaf phenology. The differences between forest canopy temperature (Tc) and Tao, which are the two most important terms attributed by the CAS model in impacting Taf, explain a large part of forest cooling and warming (May–July: R2 = 0.35; November–January: R2 = 0.51). The novel CAS model provides a feasible way to represent the energy balance within forest ecosystems and to assess its impacts on local air temperatures globally.

Selected physical properties and structure of materials based on modified polyamide 6

Selected physical properties and structure of materials based on modified polyamide 6

Reusability and composability analysis for an agent-based hierarchical modelling and simulation framework

Agent-based modeling and simulation has been proved useful in a variety of different complex adaptive systems comprised of autonomous, interacting components. To resolve the shortcoming of current agent-based modeling frameworks with respect to decomposition and modularity, this paper presents a formal hierarchical modeling and simulation framework with three–level architecture to reduce ambiguity as well as improve clarity in the model definition. The bottom level is Component Model (CM), which implements some domain-specific support functionality, such as curve motion in the physical domain, intelligent decision-making in the cognitive domain, etc. The middle level is Agent Model (AM), which describes an agent which can react to the current situation by executing a sequence of CMs. The top level is System Model (SM), which defines that a CAS model consists of several AMs and also the interactions between these AMs. In the hierarchical architecture, one SM can be built up from lower-level models, which were linked in a loosely coupled fashion via an event-driven interface. We then analyze the reusability and composability of lower-level models of this hierarchical framework in a formalized way. To demonstrate the effectiveness of the proposed solution, we develop a graphical composite modelling tool named GraphSim, and the case study concerning two social dynamics system scenarios is also presented.

The Intricate Case of Tetramethyleneethane: A Full Configuration Interaction Quantum Monte Carlo Benchmark and Multireference Coupled Cluster Studies

We have performed a full configuration interaction (FCI) quality benchmark calculation for the tetramethyleneethane molecule in the cc-pVTZ basis set employing a subset of complete active space second order perturbation theory, CASPT2(6,6), natural orbitals for the FCI quantum Monte Carlo calculation. The results are in an excellent agreement with the previous large scale diffusion Monte Carlo calculations by Pozun et al. and available experimental results. Our computations verified that there is a maximum on the potential energy surface (PES) of the ground singlet state (1A) 45° torsional angle, and the corresponding vertical singlet-triplet energy gap is 0.01 eV. We have employed this benchmark for the assessment of the accuracy of Mukherjee's coupled clusters with up to triple excitations (MkCCSDT) and CCSD tailored by the density matrix renormalization group method (DMRG). Multireference MkCCSDT with CAS(2,2) model space, though giving good values for the singlet-triplet energy gap, is not able to properly describe the shape of the multireference singlet PES. Similarly, DMRG(24,25) is not able to correctly capture the shape of the singlet surface, due to the missing dynamic correlation. On the other hand, the DMRG-tailored CCSD method describes the shape of the ground singlet state with excellent accuracy but for the correct ordering requires computation of the zero-spin-projection component of the triplet state (3B1).

Using the CAS Professional Standards: Diverse Examples of Practice ed. by Needham Y. Gulley, Shannon R. Dean, Laura A. Dean

Reviewed by: Using the CAS Professional Standards: Diverse Examples of Practice ed. by Needham Y. Gulley, Shannon R. Dean, Laura A. Dean Heidi Levine Using the CAS Professional Standards: Diverse Examples of Practice Needham Y. Gulley, Shannon R. Dean, and Laura A. Dean (Editors) Washington, DC & Fort Collins, CO: NASPA – Student Affairs Administrators in Higher Education, ACPA – college Student Educators International, and Council for the Advancement of Standards in Higher Education, 2017, 184pages, $39.95 (hardcover) More than thirty years following the publication of the first Council for the Advancement of Standards in Higher Education (CAS) standards in 1986, the editors of this volume provide a case study-based overview of how professionals can apply the standards in current practice. The editors intentionally invited authors able to reflect on practice at different institutional types and sizes and in different functional areas. In the thirty-plus years since the publication of the first CAS Standards, limited work has been published suggesting opportunities for related research (Creamer, 2003) and questioning to what extent and by whom the standards are used (Arminio, 2003). Arminio and Gochenauer (2009) provided a brief overview of the standards, their development, related research, and use in practice; but the most comprehensive review of the standards’ application was published only five years following the release of the first set of standards (Bryan, Winston, & Miller, 1991). This volume fills a niche in providing a thorough look at how the current CAS standards can be used to guide and improve professional practice. Chapter 1, by current CAS executive director, Marybeth Drechsler Sharp, offers an overview of CAS’s evolution and of the standards themselves. Drechsler Sharp presents the CAS general standards as a foundation for the area-specific standards, infusing a holistic approach to thinking about student affairs work and its affects on students, and promoting cross-functional perspectives and work. In her introduction to uses of the standards, she focuses on formal self-assessment and lays out facets of assessment that will be revisited in subsequent chapters. In chapter 2, Shannon Dean discusses using the overarching CAS general standards and learning domains to develop intended student learning outcomes. She anchors this work not only in relation to ever-increasing demands for accountability but in enhancing leaders’ ability to intentionally design programs to achieve specific student development goals. Dean also addresses the challenges and importance of engaging staff in this work, a recurring theme throughout the volume. Chapter 3, coauthored by Tim Pierson and Onie McKenzie, looks at multiple benefits of sustained use of the CAS standards from the perspective of a senior student affairs officer (SSAO). In addition to describing how the CAS model provides the basis for regular program assessment, Pierson and McKenzie discuss the value to and importance of the SSAO in fully embracing this work, as well as speaking to some of the particular challenges and benefits (e.g., prioritization) of doing program review at smaller institutions. Chapters 4 and 5 provide examples of division-wide uses of the CAS standards. Mary-Jeanne Raleigh and John Jones III review one regional institution’s use of the standards to help a student affairs division [End Page 137] shift from an accreditation-focused approach toward one that uses assessment of identified learning objectives to help drive strategic decision-making. Jennifer Wells addresses the process of instilling within a student affairs division a culture that embraces assessment. In both chapters, authors describe strategies to engage staff throughout the division and the connection to prioritizing student affairs work. Wells also provides concrete examples of the processes and mechanisms, including the development of working groups and utilization of the CAS self-assessment guides, used to undergird the creation of a comprehensive review process. In chapter 6, Adrian Rodriguez and Louann Schulze focus on assessment of academic advising in a multi-campus community college context. They discuss the usefulness of the CAS model for creating a framework to identify and assess student learning outcomes, particularly considering ways to align these processes in a functional area that is housed across multiple campuses. Their recommendations include considerations of team composition, examination of how the timing allotted to the full assessment cycle needs to reflect the...

The Genealogy of Differences in the Americas

In our target article (Fuerst & Kirkegaard, 2016, this issue), we tested the racial-cognitive ability-socioeconomic (R~CA-S) hypothesis (as proposed by, for example: Lynn, 2008). An R~CA-S model attempts to account for the apparent covariance between biogeographic ancestry (BGA) (or race1), cognitive ability and socioeconomic outcomes. It proposes that most of the association between BGA and socioeconomic outcomes is mediated by cognitive ability and that the association between BGA and cognitive ability is, in turn, dependent on factors (for example: culture, genes and epigenes) which are transmitted along genealogical lines. We examined the relation between estimated racial admixture, cognitive ability and socioeconomic outcomes across the 35 sovereign nations of the Americas as well as first-level administrative divisions (states and departments) of 4 nations (USA, Mexico, Colombia and Brazil). Generally, we found strong ecological correlations (r's .5-.8) between admixture, cognitive ability and S. Cognitive ability was found to statistically mediate the R~S association. Here we reply to the six commentaries on our paper.1. Ibarra: Discrimination as an explanationIbarra (2016) criticizes our paper on the grounds that it represents statistical justification for thesis suspected of racism and a regression in everything [the] social sciences have overcome. As part of her critique, she questions:1. Our use of ancestry as predictor (Another objection about the study of Fuerst and Kirkegaard is the variable European ancestry.)2. Our use of measured cognitive ability as mediator, both because: a. this variable is not inclusive enough. (PISA assesses three core competencies [...] but not others difficult to quantify and which, according to experts, are essential to meet the challenges of the 21st century: the psychological, moral, civic and artistic development goals.)b. individual (and therefore group) differences in cognitive ability can not have genetic basis. study falls into the same error as sociobiology, assuming that the genetic makeup determines the cognitive level [...] one wonders after reading the study of Fuerst and Kirkegaard, what sense does it have pretending to demonstrate statistically that ones belonging to race, or genetic constitution, is related to cognitive abilities?)3. Our use of geographical-environmental factors as controls. (But what seems to me most objectionable about the study presented by Fuerst and Kirkegaard is their choice of independent variables [...] their attention focuses on two variables which they consider to have considerable influence on cognitive skills: the climate, and the struggle of the body against parasites [...] there is nothing within the study to justify their choice of these variables in explaining complex outcome.)4. Our use of S-factor scores as dependent rather than independent variable. (The development of cognitive competencies is closely linked to family and school training [...] The outcome of education is complex subject affected by many variables.)5. Our lack of historical contextualization, meaning our disinclination to interpret the results from the perspective of what van den Berghe (1987) and Fuerst (2015a) called the anti-racial worldview. (But in fact, skin color and purity of race are irrelevant in sociological analysis. What is truly relevant is their permanence at the top of the constitution of power and the mechanisms that have assured them such permanence.)From Ibarra's point of view, we are making grand petitio principii (This logic departs from what is before us, and it refers back to an origin where the final outcome is pre-formed and predestined...). She apparently takes it for granted that, on average, individuals within SIRE groups, SIRE groups within regions, administrative units within countries and countries in the New World which have more ancestry relative to African and Amerindian will, in her words, show better cognitive skills and significantly higher income than the rest. …

Neonatal/infant validation study of the CAS model 740 noninvasive blood pressure monitor with the Orion/MaxIQ NIBP module

Blood pressure monitoring is an essential vital sign when caring for critically ill children. Invasive monitoring is considered the gold standard, but is not always feasible. The following study compared the CAS model 740 noninvasive blood pressure monitor with the Orion/MaxIQ NIBP module with the reference (invasive arterial measurement). We evaluated the validity of the system using the criteria provided by the Association for the Advancement of Medical Instrumentation. We performed paired measurements of 29 critically ill neonates and children. For individual paired comparisons, the mean difference in the systolic blood pressure was 2.42 mmHg (SD ± 6.3). The mean difference in the diastolic blood pressure was -1.29 mmHg (SD ± 5.45). The percentage of readings within 5, 10, and 15 mmHg for systolic blood pressure was 65.6, 86.0, and 96.8%, respectively. The percentage of readings within 5, 10, and 15 mmHg for diastolic blood pressure was 77.7, 93, and 95.5%, respectively. The CAS model 740 noninvasive blood pressure monitor with the Orion/MaxIQ NIBP module fulfills the accuracy performance criteria of the Association for the Advancement of Medical Instrumentation. This model may allow for rapid and accurate noninvasive blood pressure monitoring in neonates and children.

Market diffusion for upgrade products on the base of CAS theory

Constantly launching upgrade products is a common strategy to maintain or expand market share for innovation products with network externalities. Base on the CAS theory, we regarded a market diffusion network for original products and upgrade products as a complex adaptive system and developed a CAS model to describe the interactions between three kinds of consume clusters in order to explain the market diffusion mechanism of upgrade products. The simulation results show that the initial acceptance lever for original products plays a great role in upgrade products| successful launching in the market and their substitute to original products; distribution structure of adoption of original products influences the market share of upgrade products; and multi-product monopolists should consider the market share of original products, acceptance level for original products and upgrade products synthetically when they plan to launch upgrade products.

Turbulence Modelling of Unsteady Turbulent Flows Using the Stress Strain Lag Model

This paper reports the application of a recently developed turbulence modelling scheme known as the Cas model. This model was specifically developed to capture the effects of stress-strain misalignment observed in turbulent flows with mean unsteadiness. Earlier work has reported the approach applied within a linear k-e modelling framework, and some initial testing of it within the k-ω SST model of Menter (AIAA J 32:1598–1605, 1994). The resulting k-e-Cas and SST-Cas models have been shown to result in some of the advantages of a full Reynolds Stress transport Model (RSM), whilst retaining the computational efficiency and stability benefits of a eddy viscosity model (EVM). Here, the development of the the high-Reynolds-number version of the Cas model is outlined, with some example applications to steady and unsteady homogeneous shear flows. The SST-Cas form of the model is then applied to further, more challenging cases of 2-D flow around a NACA0012 aerofoil beyond stall and the 3-D flow around a circular cylinder in a square duct, both being flows which exhibit large, unsteady, separated flow regions. The predictions returned by a range of other common turbulence modelling schemes are included for comparison and the SST-Cas scheme is shown to return generally good results, comparable in some respects to those obtainable from far more complex schemes, for only moderate computing resource requirements.

A numerical simulation of pool boiling using CAS model

This paper presents a new numerical model, called the CAS model, for boiling heat transfer. The CAS model is based on the cellular automata (CA) technique that is integrated into the popular SIMPLER algorithm for CFD problems. In the model, the CA technique deals with the microscopic nonlinear dynamic interactions of bubbles while the traditional CFD algorithm is used to determine macroscopic system parameters such as pressure and temperature. The popular SIMPLER algorithm is employed for the CFD treatment. The model is then employed to simulate a pool boiling process. The computational results show that the CAS model can reproduce most of the basic features of boiling and capture the fundamental characteristics of boiling phenomena. The heat transfer coefficient predicted by the CAS model is in excellent agreement with the experimental data and existing empirical correlations.

Source Orientation in Human-Computer Interaction

When individuals apply social rules and social expectations while working on a computer, are they directly interacting with the computer as an independent social actor or source (the CAS model), or are they orienting to an unseen programmer or imagined person in another room (the CAM model)? Two studies provide critical tests of these competing models. In Study 1, all participants were exposed to an identical interaction with computers. In one condition, participants were told that they were dealing with computers; in another, they were told that they were interacting with the software programmers. Consistent with the CAS model, there were significant differences between the two conditions. Study 2 performed a constructive replication of Study 1 by replacing the programmer with a hypothetical networker. Again, differences between the two conditions provide evidence that people respond to the computer as an independent source of information.

Effect of silicon and calcium oxides on strontium ferrite: V.Chroust. (PRAMET a.s., Sumperk, Czech Republic.) Pokroky Praskove Metal., vol 35, no 1, 1997, 24–29. (In Czech.)

A new calcium aluminosilicate phase of composition CaAl4Si2O11 has been encountered amongst the transformation products of CaAl2Si2O8 (anorthite composition) at 14 GPa (Gautron et al., 1996). X-ray diffraction (XRD) confirms that its crystal structure is essentially the same as that of a new complex CaAl-silicate (abbreviated CAS phase) first reported by Irifune et al. (1994). The crystal structure of the CAS phase has been investigated by transmission electron microscopy (TEM). It has a hexagonal unit cell with lattice parameters a = 5.4Å and c = 12.7Å, and its space group is either P63mc, P62c or P63mmc. It is proposed that this CAS phase has a six-layer, close-packed structure so that Z = 2 and density is 3.94 g cm−3, reasonable for a phase stable at transition-zone pressures. The most plausible model for the structure of this phase arises from published refinements of hexagonal Ba-ferrites. This postulated P63mmc structure consists of octahedral layers, 34 occupied, separated by 12-coordinate Ca atoms, and by Al and Si in face-shared octahedra and in complex trigonal bipyramidal polyhedra, i.e. some Si would be five-fold coordinated. Observed TEM and XRD data are compared with calculated reflection intensities for this CAS model.

Hexagonal Ba-ferrite: a good model for the crystal structure of a new high-pressure phase CaAl 4Si 2O 11?

A new calcium aluminosilicate phase of composition CaAl 4Si 2O 11 has been encountered amongst the transformation products of CaAl 2Si 2O 8 (anorthite composition) at 14 GPa (Gautron et al., 1996). X-ray diffraction (XRD) confirms that its crystal structure is essentially the same as that of a new complex CaAl-silicate (abbreviated CAS phase) first reported by Irifune et al. (1994). The crystal structure of the CAS phase has been investigated by transmission electron microscopy (TEM). It has a hexagonal unit cell with lattice parameters a = 5.4Å and c = 12.7Å, and its space group is either P6 3mc , P 62c or P6 3 mmc . It is proposed that this CAS phase has a six-layer, close-packed structure so that Z = 2 and density is 3.94 g cm −3, reasonable for a phase stable at transition-zone pressures. The most plausible model for the structure of this phase arises from published refinements of hexagonal Ba-ferrites. This postulated P6 3 mmc structure consists of octahedral layers, 3 4 occupied, separated by 12-coordinate Ca atoms, and by Al and Si in face-shared octahedra and in complex trigonal bipyramidal polyhedra, i.e. some Si would be five-fold coordinated. Observed TEM and XRD data are compared with calculated reflection intensities for this CAS model.

Optimal granularity and scheme of parallel test generation in a distributed system

Client-Agent-Server model (CAS model) which can decrease the work load of the client by adding agent processors to the Client-Server model (CS model) is proposed and an approach to parallel test generation for logic circuits on the CAS model is presented. Two problems are considered: optimal granularity problem and optimal scheme problem. First, the problem of parallel test generation on the CAS model is formulated to analyze the effect of the granularity (grain size of target faults allocated to processors) in both cases of static and dynamic task allocation (optimal granularity problem). Then the relationship between the number of processors and the total processing time is analyzed (optimal scheme problem). From the analysis, it is shown that the CAS model can reduce the total processing time over the CS model and that there exists an optimal scheme (an optimal pair of numbers of agent processors and server processors) for the CAS model which minimizes the total processing time for a given number of processors. To corroborate the analysis, the proposed parallel test generation algorithm is implemented on a network of more than 100 workstations and experimental results for the ISCAS benchmark circuits are presented. It is shown that the experimental results are very close to the theoretical results which confirms the existence of optimal granularity and optimal scheme which minimizes the total processing time for the CAS model. >