THE NUCLEAR BORN–OPPENHEIMER METHOD APPLIED TO NUCLEAR COLLECTIVE MOTION

2002 ◽  
Vol 11 (03) ◽  
pp. 231-248
Author(s):  
NOUREDINE ZETTILI ◽  
ABDELKRIM BOUKAHIL
Keyword(s):  
Degrees Of Freedom ◽  
Ad Hoc ◽  
Collective Motion ◽  
Collective Model ◽  
Tensor Operator ◽  
Nbo Method ◽  
Inertial Parameters ◽  
Principal Axes ◽  
Selection Of ◽  
Made In

We deal with the application of the nuclear Born–Oppenheimer (NBO) method to the study of nuclear collective motion. In particular, we look at the description of nuclear rotations and vibrations. The collective operators are specified within the NBO method only to the extent of identifying the type of collective degrees of freedom we intend to describe; the operators are then determined from the dynamics of the system. To separate the collective degrees of freedom into rotational and vibrational terms, we transform the collective tensor operator from the lab fixed frame of reference to the frame defined by the principal axes of the system; this transformation diagonalizes the tensor operator. We derive a general expression for the NBO mean energy and show that it contains internal, collective and coupling terms. Then, we specify the approximations that need to be made in order to establish a connection between Bohr's collective model and the NBO method. We show that Bohr's collective Hamiltonian can be recovered from the NBO Hamiltonian only after adopting some rather crude approximations. In addition, we try to understand, in light of the NBO approach, why Bohr's collective model gives the wrong inertial parameters. We show that this is due to two major reasons: the ad hoc selection of the collective degrees of freedom within the context of Bohr's collective model and the unwarranted neglect of several important terms from the Hamiltonian.

MICROSCOPIC SELF-CONSISTENT AND COLLECTIVE MODEL DESCRIPTION OF LOW-ENERGY NUCLEAR STRUCTURE

1989 ◽  
Vol 04 (09) ◽  
pp. 2063-2146 ◽  
Author(s):  
K. HEYDE
Keyword(s):  
Nuclear Structure ◽  
Degrees Of Freedom ◽  
Collective Motion ◽  
Collective Model ◽  
Model Description ◽  
Mixed Symmetry ◽  
Self Consistent ◽  
Closed Shells ◽  
Model Approach

In the present review, an attempt is made to approach the different facets of the nucleus at low excitation energy from both a microscopic, self-consistent and a collective model approach. Some attention is given on how to relate the two “opposite” approaches to nuclear structure. In a final chapter, we discuss some newly appreciated modes in the nucleus that are specific to the proton and neutron degrees of freedom e.g. the study of intruder states near closed shells and the presence of proton-neutron mixed-symmetry collective motion.

WINTER WHEAT DEVELOPED BY THE UDMURT RESEARCH INSTITUTE OF AGRICULTURE IN COMPETITIVE VARIETY TESTING

2020 ◽  
pp. 5-16
Author(s):  
I.V. TORBINA ◽  
◽  
I.R. FARDEYEVA ◽  
Keyword(s):  
Winter Wheat ◽  
Crop Rotation ◽  
Biological Characteristics ◽  
Commercial Use ◽  
Breeding Material ◽  
Rotation Pattern ◽  
Selection Of ◽  
Variety Testing ◽  
Made In ◽  
Research Institute

The paper assesses the promising varieties of winter wheat in a competitive variety test by the main economic and biological characteristics that determine the suitability of the variety for commercial use. The object of research was the authors’ own breeding material. The experiments on the selection of winter wheat were made in the experimental crop rotation pattern of the Institute.

Evidence-based Assessment

2010 ◽  
pp. 76-98
Author(s):  
John Hunsley ◽  
Eric J. Mash
Keyword(s):  
Decision Making ◽  
Clinical Assessment ◽  
Assessment Process ◽  
Evidence Based ◽  
The Past ◽  
Specific Assessment ◽  
The Many ◽  
Selection Of ◽  
Made In

Evidence-based assessment relies on research and theory to inform the selection of constructs to be assessed for a specific assessment purpose, the methods and measures to be used in the assessment, and the manner in which the assessment process unfolds. An evidence-based approach to clinical assessment necessitates the recognition that, even when evidence-based instruments are used, the assessment process is a decision-making task in which hypotheses must be iteratively formulated and tested. In this chapter, we review (a) the progress that has been made in developing an evidence-based approach to clinical assessment in the past decade and (b) the many challenges that lie ahead if clinical assessment is to be truly evidence-based.

scholarly journals A Clinical Study to Correlate the Facial Form and Maxillary Central Incisor Tooth Form in Males and Females of Davangere Population

2016 ◽  
Vol 04 (03) ◽  
pp. 156-164
Author(s):  
Deepak Bansal ◽  
Shruti Sharma ◽  
Manjit Kumar ◽  
Amrit Khosla
Keyword(s):  
Facial Appearance ◽  
Central Incisor ◽  
Incisor Tooth ◽  
Maxillary Central Incisor ◽  
Anterior Teeth ◽  
The Face ◽  
Tooth Form ◽  
Males And Females ◽  
Selection Of ◽  
Made In

AbstractAn altered facial appearance is more difficult to face, than problems related to ill-fitting denture or eating. The selection of maxillary anterior teeth for complete denture has long posed problem in clinical practice and a controversy about the best method to employ still exists. An attempt is made in the present study to clinically correlate the face form with maxillary central incisor tooth form in males and females of Davangere population. In 1914, Leon William's projected the “the form method” where he classified facial forms as square, tapering, and ovoid. Maxillary central incisors were selected according to the facial forms.Of total 100 subjects four different tooth forms and face forms were evaluated. They are: square, ovoid, square-tapered, tapered. No significant correlation existed between face form in male and females. Females exhibited greater correlation between face forms and inverted tooth form but that correlation is not sufficient to serve as a guide for selection of anterior teeth.

Selection of Degrees of Freedom for Dynamic Analysis

1987 ◽  
Vol 109 (1) ◽  
pp. 65-69 ◽  
Author(s):  
K. W. Matta
Keyword(s):  
Finite Element ◽  
Dynamic Analysis ◽  
Degrees Of Freedom ◽  
General Purpose ◽  
Component Mode Synthesis ◽  
Complex Structures ◽  
Large Complex ◽  
Static Condensation ◽  
Basis Vectors ◽  
Selection Of

A technique for the selection of dynamic degrees of freedom (DDOF) of large, complex structures for dynamic analysis is described and the formulation of Ritz basis vectors for static condensation and component mode synthesis is presented. Generally, the selection of DDOF is left to the judgment of engineers. For large, complex structures, however, a danger of poor or improper selection of DDOF exists. An improper selection may result in singularity of the eigenvalue problem, or in missing some of the lower frequencies. This technique can be used to select the DDOF to reduce the size of large eigenproblems and to select the DDOF to eliminate the singularities of the assembled eigenproblem of component mode synthesis. The execution of this technique is discussed in this paper. Examples are given for using this technique in conjunction with a general purpose finite element computer program GENSAM[1].

Computation and cognition: issues in the foundations of cognitive science

1980 ◽  
Vol 3 (1) ◽  
pp. 111-132 ◽  
Author(s):  
Zenon W. Pylyshyn
Keyword(s):  
Tacit Knowledge ◽  
Degrees Of Freedom ◽  
Ad Hoc ◽  
Physical Systems ◽  
Symbolic Representations ◽  
Natural Domain ◽  
Human Functioning ◽  
Biological Laws ◽  
Post Hoc ◽  
Level Of Analysis

AbstractThe computational view of mind rests on certain intuitions regarding the fundamental similarity between computation and cognition. We examine some of these intuitions and suggest that they derive from the fact that computers and human organisms are both physical systems whose behavior is correctly described as being governed by rules acting on symbolic representations. Some of the implications of this view are discussed. It is suggested that a fundamental hypothesis of this approach (the “proprietary vocabulary hypothesis”) is that there is a natural domain of human functioning (roughly what we intuitively associate with perceiving, reasoning, and acting) that can be addressed exclusively in terms of a formal symbolic or algorithmic vocabulary or level of analysis.Much of the paper elaborates various conditions that need to be met if a literal view of mental activity as computation is to serve as the basis for explanatory theories. The coherence of such a view depends on there being a principled distinction between functions whose explanation requires that we posit internal representations and those that we can appropriately describe as merely instantiating causal physical or biological laws. In this paper the distinction is empirically grounded in a methodological criterion called the “cognitive impenetrability condition.” Functions are said to be cognitively impenetrable if they cannot be influenced by such purely cognitive factors as goals, beliefs, inferences, tacit knowledge, and so on. Such a criterion makes it possible to empirically separate the fixed capacities of mind (called its “functional architecture”) from the particular representations and algorithms used on specific occasions. In order for computational theories to avoid being ad hoc, they must deal effectively with the “degrees of freedom” problem by constraining the extent to which they can be arbitrarily adjusted post hoc to fit some particular set of observations. This in turn requires that the fixed architectural function and the algorithms be independently validated. It is argued that the architectural assumptions implicit in many contemporary models run afoul of the cognitive impenetrability condition, since the required fixed functions are demonstrably sensitive to tacit knowledge and goals. The paper concludes with some tactical suggestions for the development of computational cognitive theories.

New Development in High Efficiency Deep Grinding

2012 ◽  
Author(s):  
Andre D. L. Batako ◽  
Valery V. Kuzin ◽  
Brian Rowe
Keyword(s):  
Machine Tool ◽  
High Efficiency ◽  
Machining Process ◽  
Depth Of Cut ◽  
Removal Rates ◽  
Workpiece Surface ◽  
New Development ◽  
Cutting Processes ◽  
Selection Of ◽  
Made In

High Efficiency Deep Grinding (HEDG) has been known to secure high removal rates in grinding processes at high wheel speed, relatively large depth of cut and moderately high work speed. High removal rates in HEDG are associated with very efficient grinding and secure very low specific energy comparable to conventional cutting processes. Though there exist HEDG-enabled machine tools, the wide spread of HEDG has been very limited due to the requirement for the machine tool and process design to ensure workpiece surface integrity. HEDG is an aggressive machining process that requires an adequate selection of grinding parameters in order to be successful within a given machine tool and workpiece configuration. This paper presents progress made in the development of a specialised HEDG machine. Results of HEDG processes obtained from the designed machine tool are presented to illustrate achievable high specific removal rates. Specific grinding energies are shown alongside with measured contact arc temperatures. An enhanced single-pole thermocouple technique was used to measure the actual contact temperatures in deep cutting. The performance of conventional wheels is depicted together with the performance of a CBN wheel obtained from actual industrial tests.

scholarly journals Recent advances in the electrochemical construction of heterocycles

2014 ◽  
Vol 10 ◽  
pp. 2858-2873 ◽  
Author(s):  
Robert Francke
Keyword(s):  
Heterocyclic Compounds ◽  
Elevated Temperatures ◽  
Ring Formation ◽  
Environmentally Benign ◽  
Heterocyclic Chemistry ◽  
Ambient Conditions ◽  
Recent Developments ◽  
Strong Acids ◽  
Selection Of ◽  
Made In

Due to the fact that the major portion of pharmaceuticals and agrochemicals contains heterocyclic units and since the overall number of commercially used heterocyclic compounds is steadily growing, heterocyclic chemistry remains in the focus of the synthetic community. Enormous efforts have been made in the last decades in order to render the production of such compounds more selective and efficient. However, most of the conventional methods for the construction of heterocyclic cores still involve the use of strong acids or bases, the operation at elevated temperatures and/or the use of expensive catalysts and reagents. In this regard, electrosynthesis can provide a milder and more environmentally benign alternative. In fact, numerous examples for the electrochemical construction of heterocycles have been reported in recent years. These cases demonstrate that ring formation can be achieved efficiently under ambient conditions without the use of additional reagents. In order to account for the recent developments in this field, a selection of representative reactions is presented and discussed in this review.

Functional and Constructive Optimization of a Serial-Modular Industrial Robot Implemented within a Single Purpose Flexible Manufacturing Cell

2012 ◽  
Vol 186 ◽  
pp. 239-246
Author(s):  
Silviu Mihai Petrişor ◽  
Ghiţă Bârsan
Keyword(s):  
Flexible Manufacturing ◽  
Degrees Of Freedom ◽  
Industrial Robot ◽  
Kinematic Chain ◽  
Chain Structure ◽  
Calculation Algorithm ◽  
Flexible Manufacturing Cell ◽  
Manufacturing Cell ◽  
Lagrangian Equations ◽  
Selection Of

The authors of this paper aim to highlight the basic design of a flexible manufacturing cell destined for the final processing of water radiators used for AAVs, cell serviced by a serial modular industrial robot possessing in its kinematic chain structure three degrees of freedom, RRT SIL type. The paper outlines the concept, calculation and design of the (MRB) rotation module at the studied industrial robot’s base and of the (MT) translation module of the prehension device attached to the robotic arm. Depending on the organological elements that are part of the MRB rotation module and based on a rigorous dynamic study performed on robotic modules, modeling conducted with the help of Lagrangian equations of the second kind, a dynamic-organological calculation algorithm was obtained for the selection of the appropriate driving servomotor necessary to putting the rotation movable system into service. The last part of the paper deals with the flexible manufacturing cell, together with the calculations related to profitability, economy and investment return duration, following the implementation of the RRT SIL-type industrial robot.

Evolution of Arbitration System under the China FTZ Template

2018 ◽  
Vol 01 (03) ◽  
pp. 1850018
Author(s):  
Liu Huichun
Keyword(s):  
Free Trade ◽  
Ad Hoc ◽  
Third Parties ◽  
International Arbitration ◽  
Republic Of China ◽  
Free Trade Zones ◽  
Judicial Practice ◽  
New Concepts ◽  
Interim Measures ◽  
Made In

The construction of China’s free trade zones (FTZs) has levered the evolution of the arbitration regime in the People’s Republic of China (PRC). Under the FTZ template, breakthroughs in arbitration have been made in regulations, FTZ arbitration rules, arbitral proceedings and judicial practice. The development of FTZ arbitration mechanism is highlighted with the introduction of new concepts, such as ad hoc arbitration consolidation of arbitration joinder of third parties and model cases, and with the updated or expanded interpretation of the existing concepts, such as permission for the offshore arbitration for WFOEs and FIEs interim measures arbitration in combination with mediation, and the open panel of arbitrators. Regardless of the progress, many issues related to the FTZ arbitration need to be clarified, among which is the amendment of the PRC Arbitration Law and keeping it in line with the mainstream international arbitration, constitute probably the most effective way to promote and guarantee the arbitration evolution.

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