Stability of Measure In High Intellectual Ability: Preliminary Results

Despite there having been improvements in efficiency and ease on test scoring for individuals with high intellectual ability, the stability of these scores is not assured. The main objective of our research is a preliminary detection of variations in test scores from a group of children that were identified as having HIA. This was done by means of a single-time assessment of children currently following an enrichment program. A total of n=26 students participated (19 male and 7 female) in the study. The age range was between 12 and 17 years, being the average age 13.89 years (SD = 1.09 years). Differential Aptitude Test (DAT-5) and Torrance Test of Creative Thinking (TTCT) were used to assess the logical-deductive intellectual skills and creative thinking. The results show that test scores may change in a considerable amount in many supposedly HIA individuals. More than 30% of the variance cannot be attributed to common components in the two measurements points. The scores in creativity were the most fluctuating, something that could be expected of these scales having the lowest reliability indexes. Only eight participants remain steady, according to the one standard deviation criterion, and it is quite notorious that two participants show a decrease in three subscales out of five. On the other hand, two other participants have shown an increase in one subscale as well as a decrease in another. In order to foster HIA individuals and their wellbeing, it is essential to be careful with mistaken diagnoses (false-negatives and false-positives), given the fact that they will lead to developmental consequences.

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The Effect of Enrichment in The Concept of Pascal-Laws Based on STEM Education on Critical and Creative Thinking Skills of 8th Grade Student

Jurnal Inovasi Pendidikan Dasar ◽

10.22236/jipd.v5i1.89 ◽

2019 ◽

Vol 5 (1) ◽

pp. 9-16

Author(s):

Diah Mayasari

Keyword(s):

Stem Education ◽

Creative Thinking ◽

Thinking Skills ◽

Research Subjects ◽

Skill Scores ◽

8Th Grade ◽

Post Test ◽

Enrichment Program ◽

The One ◽

Critical And Creative Thinking

The study about investigation of The Effect of Enrichment in the Concept of Pascal-laws Based on STEM education on critical and creative thinking skills of 8th-grade Students are conducted as an effort to follow up the lack of development of Critical and Creative Thinking Skills on the students. The research was conducted using quasi-experiment design, the type of the one group pretest-posttest designs and involved eighth-graders aged between 14-15 years as research subjects for five meetings. The data was obtained through student worksheets and observations. Data processing to see N-Gain was used Microsoft Excel 2007 and the results showed that there was an increase in the percentage of critical thinking skill scores from 58% (pretest) to 89% (post-test) with high category increase (N-gain = 0.74). while student creativity also rose from 15% (pretest) to 81% (post-test) with moderate category increase (N-gain = 0.68). Students' creation tools on STEM's educational enrichment program are Hydraulic Glass Cleaners.

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Implications of Person Fluctuation for the Stability and Validity of Test Scores

Methodology ◽

10.1027/1614-2241.2.4.142 ◽

2006 ◽

Vol 2 (4) ◽

pp. 142-148 ◽

Cited By ~ 1

Author(s):

Pere J. Ferrando

Keyword(s):

Item Response ◽

Test Scores ◽

Temporal Stability ◽

Person Fit ◽

Item Parameters ◽

Individual Trait ◽

The Stability ◽

The Individual ◽

Different Levels ◽

Fluctuation Model

In the IRT person-fluctuation model, the individual trait levels fluctuate within a single test administration whereas the items have fixed locations. This article studies the relations between the person and item parameters of this model and two central properties of item and test scores: temporal stability and external validity. For temporal stability, formulas are derived for predicting and interpreting item response changes in a test-retest situation on the basis of the individual fluctuations. As for validity, formulas are derived for obtaining disattenuated estimates and for predicting changes in validity in groups with different levels of fluctuation. These latter formulas are related to previous research in the person-fit domain. The results obtained and the relations discussed are illustrated with an empirical example.

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Use of a Lyophilized Reference Plasma to Compare Coagulation Test Procedures

Thrombosis and Haemostasis ◽

10.1055/s-0038-1651402 ◽

1975 ◽

Vol 34 (02) ◽

pp. 426-444 ◽

Cited By ~ 3

Author(s):

J Kahan ◽

I Nohén

Keyword(s):

Oral Anticoagulant Therapy ◽

Repeated Measurements ◽

Test Procedures ◽

Coagulation Activity ◽

Close Relationship ◽

Measured Activity ◽

Test Materials ◽

The Difference ◽

The Stability ◽

The One

SummaryIn 4 collaborative trials, involving a varying number of hospital laboratories in the Stockholm area, the coagulation activity of different test materials was estimated with the one-stage prothrombin tests routinely used in the laboratories, viz. Normotest, Simplastin-A and Thrombotest. The test materials included different batches of a lyophilized reference plasma, deep-frozen specimens of diluted and undiluted normal plasmas, and fresh and deep-frozen specimens from patients on long-term oral anticoagulant therapy.Although a close relationship was found between different methods, Simplastin-A gave consistently lower values than Normotest, the difference being proportional to the estimated activity. The discrepancy was of about the same magnitude on all the test materials, and was probably due to a divergence between the manufacturers’ procedures used to set “normal percentage activity”, as well as to a varying ratio of measured activity to plasma concentration. The extent of discrepancy may vary with the batch-to-batch variation of thromboplastin reagents.The close agreement between results obtained on different test materials suggests that the investigated reference plasma could be used to calibrate the examined thromboplastin reagents, and to compare the degree of hypocoagulability estimated by the examined PIVKA-insensitive thromboplastin reagents.The assigned coagulation activity of different batches of the reference plasma agreed closely with experimentally obtained values. The stability of supplied batches was satisfactory as judged from the reproducibility of repeated measurements. The variability of test procedures was approximately the same on different test materials.

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Structure, Stability and Water Adsorption on Ultra-Thin TiO2 Supported on TiN

10.26434/chemrxiv.8425367.v1 ◽

2019 ◽

Author(s):

Jose Julio Gutierrez Moreno ◽

Marco Fronzi ◽

Pierre Lovera ◽

alan O'Riordan ◽

Mike J Ford ◽

...

Keyword(s):

Density Functional ◽

Water Adsorption ◽

Chemical Potential ◽

Energy Gap ◽

Molecular Water ◽

Structure Stability ◽

Ambient Conditions ◽

Rutile Structure ◽

The Stability ◽

The One

Interfacial metal-oxide systems with ultrathin oxide layers are of high interest for their use in catalysis. In this study, we present a density functional theory (DFT) investigation of the structure of ultrathin rutile layers (one and two TiO2 layers) supported on TiN and the stability of water on these interfacial structures. The rutile layers are stabilized on the TiN surface through the formation of interfacial Ti–O bonds. Charge transfer from the TiN substrate leads to the formation of reduced Ti3+ cations in TiO2. The structure of the one-layer oxide slab is strongly distorted at the interface, while the thicker TiO2 layer preserves the rutile structure. The energy cost for the formation of a single O vacancy in the one-layer oxide slab is only 0.5 eV with respect to the ideal interface. For the two-layer oxide slab, the introduction of several vacancies in an already non-stoichiometric system becomes progressively more favourable, which indicates the stability of the highly non-stoichiometric interfaces. Isolated water molecules dissociate when adsorbed at the TiO2 layers. At higher coverages the preference is for molecular water adsorption. Our ab initio thermodynamics calculations show the fully water covered stoichiometric models as the most stable structure at typical ambient conditions. Interfacial models with multiple vacancies are most stable at low (reducing) oxygen chemical potential values. A water monolayer adsorbs dissociatively on the highly distorted 2-layer TiO1.75-TiN interface, where the Ti3+ states lying above the top of the valence band contribute to a significant reduction of the energy gap compared to the stoichiometric TiO2-TiN model. Our results provide a guide for the design of novel interfacial systems containing ultrathin TiO2 with potential application as photocatalytic water splitting devices.

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Stability of a one-dimensional morphoelastic model for post-burn contraction

Journal of Mathematical Biology ◽

10.1007/s00285-021-01648-5 ◽

2021 ◽

Vol 83 (3) ◽

Author(s):

Ginger Egberts ◽

Fred Vermolen ◽

Paul van Zuijlen

Keyword(s):

Wound Healing ◽

Residual Stresses ◽

Truncation Error ◽

Signaling Molecules ◽

Discrete Problem ◽

One Dimensional ◽

Stability Constraint ◽

Biological Interpretation ◽

The Stability ◽

The One

AbstractTo deal with permanent deformations and residual stresses, we consider a morphoelastic model for the scar formation as the result of wound healing after a skin trauma. Next to the mechanical components such as strain and displacements, the model accounts for biological constituents such as the concentration of signaling molecules, the cellular densities of fibroblasts and myofibroblasts, and the density of collagen. Here we present stability constraints for the one-dimensional counterpart of this morphoelastic model, for both the continuous and (semi-) discrete problem. We show that the truncation error between these eigenvalues associated with the continuous and semi-discrete problem is of order $${{\mathcal {O}}}(h^2)$$ O ( h 2 ) . Next we perform numerical validation to these constraints and provide a biological interpretation of the (in)stability. For the mechanical part of the model, the results show the components reach equilibria in a (non) monotonic way, depending on the value of the viscosity. The results show that the parameters of the chemical part of the model need to meet the stability constraint, depending on the decay rate of the signaling molecules, to avoid unrealistic results.

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One-Dimensional Organic–Inorganic Material (C6H9N2)2BiCl5: From Synthesis to Structural, Spectroscopic, and Electronic Characterizations

International Journal of Molecular Sciences ◽

10.3390/ijms22042030 ◽

2021 ◽

Vol 22 (4) ◽

pp. 2030

Author(s):

Hela Ferjani ◽

Hammouda Chebbi ◽

Mohammed Fettouhi

Keyword(s):

Hydrogen Bonding ◽

Density Functional ◽

Crystal Packing ◽

Diffuse Reflectance Spectrum ◽

Enrichment Ratio ◽

One Dimensional ◽

Organic Part ◽

Fukui Indices ◽

The Stability ◽

The One

The new organic–inorganic compound (C6H9N2)2BiCl5 (I) has been grown by the solvent evaporation method. The one-dimensional (1D) structure of the allylimidazolium chlorobismuthate (I) has been determined by single crystal X-ray diffraction. It crystallizes in the centrosymmetric space group C2/c and consists of 1-allylimidazolium cations and (1D) chains of the anion BiCl52−, built up of corner-sharing [BiCl63−] octahedra which are interconnected by means of hydrogen bonding contacts N/C–H⋯Cl. The intermolecular interactions were quantified using Hirshfeld surface analysis and the enrichment ratio established that the most important role in the stability of the crystal structure was provided by hydrogen bonding and H···H interactions. The highest value of E was calculated for the contact N⋯C (6.87) followed by C⋯C (2.85) and Bi⋯Cl (2.43). These contacts were favored and made the main contribution to the crystal packing. The vibrational modes were identified and assigned by infrared and Raman spectroscopy. The optical band gap (Eg = 3.26 eV) was calculated from the diffuse reflectance spectrum and showed that we can consider the material as a semiconductor. The density functional theory (DFT) has been used to determine the calculated gap, which was about 3.73 eV, and to explain the electronic structure of the title compound, its optical properties, and the stability of the organic part by the calculation of HOMO and LUMO energy and the Fukui indices.

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A TWELFTH-ORDER FOUR-STEP FORMULA FOR THE NUMERICAL INTEGRATION OF THE ONE-DIMENSIONAL SCHRÖDINGER EQUATION

International Journal of Modern Physics C ◽

10.1142/s0129183103005194 ◽

2003 ◽

Vol 14 (08) ◽

pp. 1087-1105 ◽

Cited By ~ 10

Author(s):

ZHONGCHENG WANG ◽

YONGMING DAI

Keyword(s):

Schrödinger Equation ◽

Numerical Integration ◽

Schrodinger Equation ◽

Numerical Test ◽

New Method ◽

Step Method ◽

One Dimensional ◽

The Stability ◽

The One ◽

Order Four

A new twelfth-order four-step formula containing fourth derivatives for the numerical integration of the one-dimensional Schrödinger equation has been developed. It was found that by adding multi-derivative terms, the stability of a linear multi-step method can be improved and the interval of periodicity of this new method is larger than that of the Numerov's method. The numerical test shows that the new method is superior to the previous lower orders in both accuracy and efficiency and it is specially applied to the problem when an increasing accuracy is requested.

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First Principles Investigation of the Stability and the Chemical Behavior of Hydrogen in ThCoH4

Zeitschrift für Naturforschung B ◽

10.1515/znb-2011-0308 ◽

2011 ◽

Vol 66 (3) ◽

pp. 269-274

Author(s):

Samir F. Matar

Keyword(s):

Negative Charge ◽

Geometry Optimization ◽

Full Geometry Optimization ◽

Intermetallic Matrix ◽

Charge Analysis ◽

The Stability ◽

The One ◽

Site Selective ◽

Bader Charge Analysis ◽

Positively Charged

We address the changes in the electronic structure brought by the insertion of hydrogen into ThCo leading to the experimentally observed ThCoH4. Full geometry optimization positions the hydrogen in three sites stabilized in the expanded intermetallic matrix. From a Bader charge analysis, hydrogen is found to be in a narrow iono-covalent (~−0.6) to covalent (~−0.3) bonding which should enable site-selective desorption. The overall chemical picture shows a positively charged Thδ+ with the negative charge redistributed over a complex anion {CoH4}δ− with δ~1.8. Nevertheless this charge transfer remains far from the one in the more ionic hydridocobaltate anion CoH54− in Mg2CoH5, due to the largely electropositive character of Mg.

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The M/G/1 queue with negative customers

Advances in Applied Probability ◽

10.1017/s0001867800048618 ◽

1996 ◽

Vol 28 (02) ◽

pp. 540-566 ◽

Cited By ~ 5

Author(s):

Peter G. Harrison ◽

Edwige Pitel

Keyword(s):

Iterative Solution ◽

Single Server ◽

Negative Customers ◽

Poisson Arrival ◽

First Case ◽

Full Study ◽

Service Times ◽

The Stability ◽

The One ◽

Iterative Solution Method

We derive expressions for the generating function of the equilibrium queue length probability distribution in a single server queue with general service times and independent Poisson arrival streams of both ordinary, positive customers and negative customers which eliminate a positive customer if present. For the case of first come first served queueing discipline for the positive customers, we compare the killing strategies in which either the last customer in the queue or the one in service is removed by a negative customer. We then consider preemptive-restart with resampling last come first served queueing discipline for the positive customers, combined with the elimination of the customer in service by a negative customer—the case of elimination of the last customer yields an analysis similar to first come first served discipline for positive customers. The results show different generating functions in contrast to the case where service times are exponentially distributed. This is also reflected in the stability conditions. Incidently, this leads to a full study of the preemptive-restart with resampling last come first served case without negative customers. Finally, approaches to solving the Fredholm integral equation of the first kind which arises, for instance, in the first case are considered as well as an alternative iterative solution method.

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Stability of Viscoelastic Channel Flow

Volume 8: Heat Transfer, Fluid Flows, and Thermal Systems, Parts A and B ◽

10.1115/imece2007-41830 ◽

2007 ◽

Author(s):

Nariman Ashrafi

Keyword(s):

Reynolds Number ◽

Viscosity Ratio ◽

Weissenberg Number ◽

Base Flow ◽

Galerkin Projection ◽

Large Reynolds Number ◽

One Dimensional ◽

Stress Effects ◽

The Stability ◽

The One

The nonlinear stability and bifurcation of the one-dimensional channel (Poiseuille) flow is examined for a Johnson-Segalman fluid. The velocity and stress are represented by orthonormal functions in the transverse direction to the flow. The flow field is obtained from the conservation and constitutive equations using the Galerkin projection method. Both inertia and normal stress effects are included. The stability picture is dramatically influenced by the viscosity ratio. The range of shear rate or Weissenberg number for which the base flow is unstable increases from zero as the fluid deviates from the Newtonian limit as decreases. Typically, two turning points are observed near the critical Weissenberg numbers. The transient response is heavily influenced by the level of inertia. It is found that the flow responds oscillatorily. When the Reynolds number is small, and monotonically at large Reynolds number when elastic effects are dominated by inertia.

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