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Application of Analytic Databases to Support Decision Making in Structural Engineering
J. Szelka, Z. Wrona
Archives of Civil Engineering , 2010, DOI: 10.2478/v.10169-010-0009-6
Abstract: Complex structural engineering projects that involve information-gathering and decision-making processes need to be approached with appropriate systems and tools. As transactional databases are found to be insufficient for this purpose, engineers are adopting multidimensional information systems that have been successfully used in other areas of management, especially business. Decision making problems encountered in structural engineering are generally multi-stage operations of a considerable degree of complexity. It is essential that such analyses are conducted by advanced information resources and complex relationships between data objects. Advanced information resources require, however, advanced information operations including data gathering, storing, processing and distribution. In order to handle the information complexity, it is vital to apply a systems approach. This approach can be used to describe structures and functions of engineering systems, as well as develop information and functional models of database systems with the aim of performing the most appropriate information-decision processes. It is also important that suitable software tools are applied. One of the most common information solutions used in various areas of management, including structural engineering, is a database system enabling efficient organization and processing of data. Information resources are stored in a database using two-dimensional tables linked by relationships. Data structures are optimized for processing current (transactional) data. Data handling is performed by using algorithmic applications referred to as database management systems. Database systems are applied to support a majority of information and information-decision tasks. Their suitability to support decision making processes, particularly analyses, is considered to be limited, which is mainly due to little information and functional flexibility. The insufficient flexibility of information systems may cause various data formats, especially those from external systems, and "rigid" data structures, which need to be defined as early as at the system design stage, not accepted. Similar limitations are reported for a functional system, the use of which is strictly defined, e.g. data search or aggregation. It has been necessary to develop a new concept of a database system so that the expectations of various areas of data management, whether related to business or engineering, can be met. Databases are now optimized with a view to perform complex analyses, and not only support current, transactional operations. Multidimensional database structures and the corresponding tools for data processing make it possible to use different data sources, and create advanced aggregates and queries, whose forms do not need to be defined at the system design stage. It can be assumed that since analytic processes required for structural engineering projects are similar in structure to those performed in the are
The electric double layer in hydriding metals
K. Jamroziak,W. Jargulinski,J. Szelka
Journal of Achievements in Materials and Manufacturing Engineering , 2008,
Abstract: Purpose: The effect of penetration hydrogen into fatigue load metals is widely investigated by many researchers.Hydrogen is the chemical element which plays negative role in fatigue durability of structures. It decides on fatiguebrittle cracking. In the paper authors carry out an analysis of fatigue durability. Making use of naturally coming intoexistence the electric double layer phenomenon authors discussed the model of absorbing hydrogen into fatigue gap.Design/methodology/approach: A proposed model of the mechanism of hydrogen absorption by metal wasbased on particle hydrogen and water vapor from the air.Findings: It assumes that the EDL has crucial role in intercepting of polar dipole particles of hydrogenand water’s vapor, especially in an already formed fatigue micro-gaps and gaps by effects of its electrostaticattraction force. The authors assume that the main source of hydrogen is water’s vapor, and number of hydrogendipoles is negligible.Practical implications: The problems of metals’ fragility/durability were also discussed in other papersin which author mainly tried to develop new methods of materials’ production with the consideration of assumedfatigue durability.Originality/value: Currently, in progress are works on proposing a model for hydrogen absorption by metal.Such approach to optimization in production and development of the new technologies is an essence of modernconstructions that work in all variety of mechanical stress conditions.
New components of the mercury’s perihelion precession  [PDF]
J. J. Smulsky
Natural Science (NS) , 2011, DOI: 10.4236/ns.2011.34034
Abstract: The velocity of perihelion rotation of Mercury's orbit relatively motionless space is computed. It is prove that it coincides with that calculated by the Newtonian interaction of the planets and of the compound model of the Sun’s rotation.
Simple General Purpose Ion Beam Deceleration System Using a Single Electrode Lens  [PDF]
J. Lopes, J. Rocha
World Journal of Engineering and Technology (WJET) , 2015, DOI: 10.4236/wjet.2015.33014
Abstract: Ion beam deceleration properties of a newly developed low-energy ion beam implantation system were studied. The objective of this system was to produce general purpose low-energy (5 to 15 keV) implantations with high current beam of hundreds of μA level, providing the most wide implantation area possible and allowing continuously magnetic scanning of the beam over the sample(s). This paper describes the developed system installed in the high-current ion implanter at the Laboratory of Accelerators and Radiation Technologies of the Nuclear and Technological Cam-pus, Sacavém, Portugal (CTN).
Constraints on velocity anisotropy of spherical systems with separable augmented densities
J. An
Physics , 2011, DOI: 10.1088/0004-637X/736/2/151
Abstract: If the augmented density of a spherical anisotropic system is assumed to be multiplicatively separable to functions of the potential and the radius, the radial function, which can be completely specified by the behavior of the anisotropy parameter alone, also fixes the anisotropic ratios of every higher-order velocity moment. It is inferred from this that the non-negativity of the distribution function necessarily limits the allowed behaviors of the radial function. This restriction is translated into the constraints on the behavior of the anisotropy parameter. We find that not all radial variations of the anisotropy parameter satisfy these constraints and thus that there exist anisotropy profiles that cannot be consistent with any separable augmented density.
On the augmented density of a spherical anisotropic dynamic system
J. An
Physics , 2010, DOI: 10.1111/j.1365-2966.2011.18324.x
Abstract: This paper presents a set of new conditions on the augmented density of a spherical anisotropic system that is necessary for the underlying two-integral phase-space distribution function to be non-negative. In particular, it is shown that the partial derivatives of the Abel transformations of the augmented density must be non-negative. Applied for the separable augmented densities, this recovers the result of van Hese et al. (2011).
Fractional calculus, completely monotonic functions, a generalized Mittag-Leffler function and phase-space consistency of separable augmented densities
J. An
Physics , 2012,
Abstract: Under the separability assumption on the augmented density, a distribution function can be always constructed for a spherical population with the specified density and anisotropy profile. Then, a question arises, under what conditions the distribution constructed as such is non-negative everywhere in the entire accessible subvolume of the phase-space. We rediscover necessary conditions on the augmented density expressed with fractional calculus. The condition on the radius part R(r^2) -- whose logarithmic derivative is the anisotropy parameter -- is equivalent to R(1/w)/w being a completely monotonic function whereas the condition on the potential part is stated as its derivative up to the order not greater than 3/2-b being non-negative (where b is the central limiting value for the anisotropy parameter). We also derive the set of sufficient conditions on the separable augmented density for the non-negativity of the distribution, which generalizes the condition derived for the generalized Cuddeford system by Ciotti & Morganti to arbitrary separable systems. This is applied for the case when the anisotropy is parameterized by a monotonic function of the radius of Baes & Van Hese. The resulting criteria are found based on the complete monotonicity of generalized Mittag-Leffler functions.
When is an axisymmetric potential separable?
J. An
Physics , 2013, DOI: 10.1093/mnras/stt1498
Abstract: An axially symmetric potential psi(R,z)=psi(r,theta) is completely separable if the ratio s:k is constant. Here r*s=d^2(r^2*psi)/dr/d(theta) and k=d^2(psi)/dR/dz. If beta=s/k, then the potential admits an integral of the form of I=(L^2+beta*v_z^2)/2+xi where xi is some function of positions determined by the potential psi. More generally, an axially symmetric potential respects the third axisymmetric integral of motion -- in addition to the classical integrals of the Hamiltonian and the axial component of the angular momentum -- if there exist three real constants a,b,c (not all simultaneously zero, a^2+b^2+c^2>0) such that a*s+b*h+c*k=0 where r*h=d^2(r*psi)/d(sigma)/d(tau) and (sigma,tau) is the parabolic coordinate in the meridional plane such that sigma^2=r+z and tau^2=r-z.
KROZ NA？U ZEMLJU: IV. KONFERENCIJA STRU？NJAKA ZA KRMNO BILJE JUGOSLAVIJE
？., J.
- , 1955,
Abstract: Hr？ak ID: 18280
U STUDENOM 1956. ORGANIZIRALA JE ZAGREBA？KA PODRU？NICA DRU？TVA AGRONOMA PREDAVANJE O ULOZI I ZADACIMA NAU？NO ISTRA？IVA？KOG RADA U POLJOPRIVREDI
？., J.
- , 1956,
Abstract: Hr？ak ID: 17783
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