scholarly journals About Strong Dependence of the Complexity of Analysis of the Random 3-CNF Formulas on the Ratio of Number of Clauses to the Number of Variables

2021 ◽  
Author(s):  
Sergey I. Uvarov
Keyword(s):  
Computational Experiment ◽  
Strong Dependence ◽  
Exponential Dependence ◽  
Exponential Component ◽  
R Ratio ◽  
R Value ◽  
Cnf Formulas

The results of a computational experiment on the assessment of the complexity of proving the unsatisfiability of random 3-CNF logical formulas are presented. The dependence of the complexity of this proving on the R-ratio of the number of clauses to the number of variables is demonstrated. The computational experiment was carried out for the range of the N-number of variables from 256 to 512. An exponential dependence of the median complexity of proving the unsatisfiability of formulas on the number of variables was revealed for each of R value: 4.3, 4.6, 5.0, 5.5, 6.0. A formula is constructed that approximates the results of the experiment. According to this formula the exponential component of the median complexity of the analysis of random 3-CNF is estimated as 2 to the power N / (8.4R-17.8).

CBED analysis of impurity distributions in AlN

1990 ◽  
Vol 48 (4) ◽  
pp. 214-215
Author(s):  
Daniel Callahan ◽  
G. Thomas
Keyword(s):  
Aluminum Nitride ◽  
Bulk Material ◽  
Strong Dependence ◽  
Lattice Parameter ◽  
Promising Technique ◽  
Nitride Ceramics ◽  
Surface Phases ◽  
Convergent Beam ◽  
Oxygen Impurities

Oxygen impurities may significantly influence the properties of nitride ceramics with a strong dependence on the microstructural distribution of the impurity. For example, amorphous oxygen-rich grain boundary phases are well-known to cause high-temperature mechanical strength degradation in silicon nitride whereas solutionized oxygen is known to decrease the thermal conductivity of aluminum nitride. Microanalytical characterization of these impurities by spectral methods in the AEM is complicated by reactions which form oxygen-rich surface phases not representative of the bulk material. Furthermore, the impurity concentrations found in higher quality ceramics may be too low to measure by EDS or PEELS. Consequently an alternate method for the characterization of impurities in these ceramics has been investigated.Convergent beam electron diffraction (CBED) is a promising technique for the study of impurity distributions in aluminum nitride ceramics. Oxygen is known to enter into stoichiometric solutions with AIN with a consequent decrease in lattice parameter.

THE c/r RATIO OF MARTENSITIC PLATES IN Fe-Ni ALLOYS

1982 ◽  
Vol 43 (C4) ◽  
pp. C4-535-C4-540
Author(s):  
R. Datta ◽  
V. Raghavan
Keyword(s):  
Ni Alloys ◽  
R Ratio

ARIC Hemostasis Study-IV. Intraindividual Variability and Reliability of Hemostatic Factors

1995 ◽  
Vol 73 (02) ◽  
pp. 256-260 ◽  
Author(s):  
Nghia D Nguyen ◽  
Habib Ghaddar ◽  
Valarie Stinson ◽  
Lloyd E Chambless ◽  
Kenneth K Wu ◽  
...  
Keyword(s):  
Plasminogen Activator ◽  
Plasminogen Activator Inhibitor ◽  
Protein S ◽  
Coagulation Factors ◽  
Total Variance ◽  
Intraindividual Variability ◽  
Plasminogen Activator Inhibitor 1 ◽  
Platelet Factor ◽  
Hemostatic Factors ◽  
R Value

SummaryWe have recently reported the short-term intraindividual variability of several coagulation factors and inhibitors included in the ARIC study (Chambless et al. Ann Epidemiol 1992; 2:723). In this paper, we reported the intraindividual variability results of additional hemostatic factors. Blood samples were collected for hemostatic assays three times at 1-2-week intervals from 39 subjects recruited from 4 ARIC field centers. The contributions of within-person, processing and assay (designated “method”) and between-person variances to the total variance were estimated and from them the reliability coefficient, R, was computed as the proportion of total variance in the between-person component. The R value was high for (β-thromboglobulin and tissue- plasminogen activator: 0.83 and 0.81, respectively; and intermediate for D-dimer and plasminogen activator inhibitor-1: 0.73 and 0.72, respectively. Protein S (total and free) and platelet factor 4 had low repeatability (R<0.50) derived mostly from “method” variability while low R value (0.03) for fibrinopeptide A was attributed to high “method” and “within-person” variability. Gender, age and the level of hemostatic factors did not influence the intraindividual variability.

SERUM PROLACTINE LEVEL IN PATIENTS OF PSORIASIS VULGARIS AND ITS CORRELATION WITH DISEASE SEVERITY: A CASE-CONTROL STUDY

2019 ◽  
Vol 3 (6) ◽  
Author(s):  
Pawan Kumar Saini ◽  
Devendra Yadav ◽  
Rozy Badyal ◽  
Suresh Jain ◽  
Arti Singh ◽  
...  
Keyword(s):  
Disease Severity ◽  
Prolactin Level ◽  
Case Control Study ◽  
Statistical Significance ◽  
Case Control ◽  
Serum Prolactin ◽  
P Value ◽  
Serum Prolactin Level ◽  
R Value ◽  
Control Study

Background: Psoriasis is an autoimmune chronic inflammatory disorder affecting the skin mediated by T-lymphocytes resulting in production of cytokines which cause hyperproliferation of keratinocytes.  Several factors and hormones like Prolactin have an action similar to these cytokines in promoting the multiplication of keratinocytes and other cells like lymphocytes and epithelial cells may have a role on the etiopathogenesis of psoriasis. Aim:-The aim of study is to compare the serum Prolactin levels in patients of psoriasis with a control group. Setting and study design: This is a case-control study conducted in the department of Dermatology, Venereology and Leprosy GMC, Kota over a period of 1year from July 2017 to June 2018 Material and method: The study included 100 cases of psoriasis (60 males and 40 females) and 100 controls similar for age and sex. Serum Prolactin levels were measured by ECLIA and results were obtained. Statistical analysis: Mean and standard deviation were calculated for each variable. Statistical significance of the results was analyzed using correlation analysis (Pearson correlation coefficient) and independent samples t-test. Statistical significance was assumed at p value<0.05. Result: Serum Prolactin level was significantly higher in cases of psoriasis compared to controls (p-value <0.001). PASI score and serum Prolactin levels were found to have a positive correlation (r value = 0.337; p-value: 0.001). No significant  correlation was found between serum levels of Prolactin and duration of disease r value= -0.034, P value =0.733). Serum Prolactin level was higher in male patients compared to females patients. Conclusion:- High serum Prolactin may be a biological marker of disease severity in psoriasis and may have a role in the pathogenesis of psoriasis. Further studies with large sample size are required to confirm this hypothesis.

What Does Rent Give to Federal Budget (on the Russia's Budget Dependence upon "Oil Dollars")

2004 ◽  
pp. 51-69 ◽  
Author(s):  
E. Sharipova ◽  
I. Tcherkashin
Keyword(s):  
Oil And Gas ◽  
Strong Dependence ◽  
Oil Prices ◽  
Federal Budget ◽  
Oil And Gas Industry ◽  
Gas Industry ◽  
Resource Rent ◽  
Tax Legislation ◽  
Russian Economy ◽  
The Government

Federal tax revenues from the main sectors of the Russian economy after the 1998 crisis are examined in the article. Authors present the structure of revenues from these sectors by main taxes for 1999-2003 and prospects for 2004. Emphasis is given to an increasing dependence of budget on revenues from oil and gas industries. The share of proceeds from these sectors has reached 1/3 of total federal revenues. To explain this fact world oil prices dynamics and changes in tax legislation in Russia are considered. Empirical results show strong dependence of budget revenues on oil prices. The analysis of changes in tax legislation in oil and gas industry shows that the government has managed to redistribute resource rent in favor of the state.

The Risks of Russia's Debt Policy against the Background of the Global Debt Crisis

2012 ◽  
pp. 80-97
Author(s):  
B. Kheifets
Keyword(s):  
Debt Crisis ◽  
Strong Dependence ◽  
Domestic Debt ◽  
Debt Market ◽  
State Paternalism ◽  
High Level ◽  
External Borrowing ◽  
Pension Liabilities ◽  
Policy Problems ◽  
Debt Policy

The paper discusses the debt component of the current global crisis, which becomes stronger in 2011—2012. The Russian economy is analyzed in terms of its debt stability: a thorough analysis shows that it is not quite adequate. This paper presents the main problems that could be exacerbated by the global debt crisis (strong dependence of the budget on the volatility of oil prices, deterioration of conditions for external borrowing and overheat of the domestic debt market, too high public pension liabilities, substantial corporate debt and high level of state paternalism in regard to big business). Some measures to address Russian debt policy problems are proposed.

Behavior of copper in CdGeAs2 crystals

2002 ◽  
Vol 719 ◽  
Author(s):  
Valeriy G. Voevodin ◽  
Olga V. Voevodina ◽  
Svetlana A. Bereznaya ◽  
Zoya V. Korotchenko ◽  
Melvin C. Ohmer ◽  
...  
Keyword(s):  
Exponential Dependence ◽  
Saturation Solubility ◽  
Diffusion Temperature

AbstractWe present an investigation of the diffusion and melt doping of Cu in CdGeAs2. Cu was found to be an acceptor, its introduction in the melt allowed the controlled introduction of holes from ∼8·1016 cm-3 to ∼1·1018 cm -3. Introduction of Cu from the melt was also found to improve the homogeneity of the crystal. The saturation solubility of Cu introduced via diffusion doping was found to have an exponential dependence on the diffusion temperature, from 723 K to 873 K, obeying the equation N = N0 exp (- δH / kT) with the parameters N0 = 6.10+19 cm-3, δH = 0.3 eV, and k equal to Boltzman's constant. From 873 K to 923 K, the saturation solubility was found to decrease exponentially with temperature.

Microhardness Testing on Via Fill Material for Via In Pad Technology

2003 ◽  
Author(s):  
Norman J. Armendariz ◽  
Carolyn McCormick
Keyword(s):  
Printed Circuit Board ◽  
Failure Modes ◽  
Strong Dependence ◽  
Circuit Board ◽  
Electrical Performance ◽  
Gravimetric Analysis ◽  
Passive Components ◽  
Root Cause ◽  
Fill Material ◽  
Signal Routing

Abstract Via in pad PCB (Printed Circuit board) technology for passive components such as chip capacitors and resistors, provides the potential for improved signal routing density and reduced PCB area. Because of these improvements there is the potential for PCB cost reduction as well as gains in electrical performance through reduced impedance and inductance. However, not long after the implementation, double digit unit failures for solder joint electrical opens due to capacitor “tombstoning” began to occur. Failure modes included via fill material (solder mask) protrusion from the via as well as “out gassing” and related “tombstoning.” This failure analysis involved investigating a strong dependence on PCB supplier and, less obviously, manufacturing site. Other factors evaluated included via fill material, drill size, via fill thermal history and via fill amount or fill percent. The factor most implicated was incomplete cure of the via fill material. Previous thermal gravimetric analysis methods to determine level of polymerization or cure did not provide an ability to measure and demonstrate via fill cure level in small selected areas or its link to the failures. As a result, there was a metrology approach developed to establish this link and root-cause the failures in the field, which was based on microhardness techniques and noncontact via fill measuring metrologies.

Can the mass balance of the entire glacier area of the Tien Shan be estimated?

1992 ◽  
Vol 16 ◽  
pp. 173-179
Author(s):  
M.B. Dyurgerov ◽  
M.G. Kunakhovitch ◽  
V.N. Mikhalenko ◽  
A. M. Sokalskaya ◽  
V. A. Kuzmichenok
Keyword(s):  
Mass Balance ◽  
Vertical Profile ◽  
River Basins ◽  
Annual Runoff ◽  
Snow Accumulation ◽  
Tien Shan ◽  
Exponential Dependence ◽  
Glacier Area ◽  
Equilibrium Line Altitude ◽  
Boundary Area

The total area of glacierization of the Tien Shan in the boundary area of the USSR is about 8000 km2. The computation of mass balance was determined for this area in 12 river basins.In computation procedure, the vertical profile of snow accumulation in these regions and exponential dependence of variation of ablation with altitude are used. Thus the mass balance in each basin, bn, was calculated on the basis of these curves and represented in its relation with the equilibrium line altitude (ELA). It is shown that the relation ELA = f(bn) is linear when the range of bn values is close to zero, and in all altitude intervals this relation can be described by hypsographic curves, in all basins bn positive up to an ELA elevation of 3450 to 3500 m a.s.l. For average annual altitude of ELA, bn is negative for all regions. So the glaciers of these mountains add about 4 km3 of water to the total annual runoff.

Sign in / Sign up

Export Citation Format

Share Document