Generated Data Base Research Articles

Evaluation of the significance of different mix design variables on asphalt mixtures’ cracking performance measured by laboratory performance tests

Cracking is one of the primary distresses for asphalt pavements. This study is motivated to investigate the significance of the various mix design variables in determining the cracking performance of asphalt mixtures including both intermediate and thermal cracking performance, contributing to a better understanding of the mix design to improve the mixture cracking performance and promoting the development and implementation of the performance related specification and performance based specification. Total 20 mixtures were tested and evaluated in this study. The most current state of the practice mixture performance tests, including the Complex Modulus (E*) test, Semi Circular Bending (SCB) test, Disk Shaped Compact Tension (DCT) test and Direct Tension Cyclic Fatigue (DTCF) test were conducted on these mixtures for characterization of their cracking performance. The advanced statistical analysis methods were employed on the generated data base to investigate the significance of the mix design variables on determining the cracking performance parameters measured from the laboratory tests. The correlations between the various cracking performance parameters measured from the tests were also evaluated in this study. The results show that the binder related mix variables play the significant role for determining both the low temperature and durability cracking performance of asphalt mixture. For evaluation of the mixture fatigue cracking performance, several aggregate related variables in addition to binder variables are identified as the significant factors. Correlation analysis shows that mixture rheological based cracking parameter G-Rm does not show the strong correlations with neither the facture indices measured from the DCT and SCB tests nor the fatigue parameters measured from the DTCF test. This study also develops a simplified linear regression model as a predesign tool for evaluation and prediction of mixture cracking performance in general.

In-silico Screening of Selected Apiaceae Plants as Melanogenesis Inhibitors and their Predicted Skin Permeability

Tyrosinase-related protein 1 (TYRP1) is a member of tyrosinase enzyme family which is metal-containing glycoproteins localized in melanosomes where the melanin biosynthesis occurs. The downregulation of tyrosinase is the most protruding approach for the development of skin whitening and depigmentation agents, however, TYRP1 downregulation is considered a novel target for melanogenesis inhibition and is still under clinical investigations for treatment of malignant melanoma. In the present study, virtual screening using glide extra-precision docking of an in-house generated data base of 400 natural compounds belonging to family Apiaceae for TYRP1 inhibitors was performed for the first time. luteolin-7-apiosylglucoside from celery followed by 4-(beta-D-glucopyranosyloxy)benzoic acid then caffeoylquininc acid from anise showed highly potent melanogenesis inhibition even more than the synthetic standard inhibitors such as azelaic and kojic acids. These natural inhibitors exhibited good predicted skin permeability after processing with Qikprop module. Although they had slow predicted transdermal penetration rates, but these rates can be enhanced through optimizing their topical pharmaceutical formulations.

Hydrological inferences through morphometric analysis of lower Kosi river basin of India for water resource management based on remote sensing data

Satellite based remote sensing technology has proven to be an effectual tool in analysis of drainage networks, study of surface morphological features and their correlation with groundwater management prospect at basin level. The present study highlights the effectiveness and advantage of remote sensing and GIS-based analysis for quantitative and qualitative assessment of flood plain region of lower Kosi river basin based on morphometric analysis. In this study, ASTER DEM is used to extract the vital hydrological parameters of lower Kosi river basin in ARC GIS software. Morphometric parameters, e.g., stream order, stream length, bifurcation ratio, drainage density, drainage frequency, drainage texture, form factor, circularity ratio, elongation ratio, etc., have been calculated for the Kosi basin and their hydrological inferences were discussed. Most of the morphometric parameters such as bifurcation ratio, drainage density, drainage frequency, drainage texture concluded that basin has good prospect for water management program for various purposes and also generated data base that can provide scientific information for site selection of water-harvesting structures and flood management activities in the basin. Land use land cover (LULC) of the basin were also prepared from Landsat data of 2005, 2010 and 2015 to assess the change in dynamic of the basin and these layers are very noteworthy for further watershed prioritization.

Optimization of the Blank Holder Force Using Genetic Algorithm Method in Case of a U - Shaped Part

In case of sheet metal forming the main dimensional errors are caused by the springback phenomena. The present work deals with numerical simulation related to draw bending and springback of U - shaped parts. The current paper is trying to prove out the important role of the blank holder force variation during the forming process. The Dynaform 5.8 software was used to simulate the forming process, in which the blank holder force varies in four steps between 0 and 50 kN. The factorial simulations test plan was made to cover completely the variation domain and 256 simulations were necessarily to be performed. The part obtained after each simulation is analyzed and measured to quantify the errors caused by springback. Parameters as: angle between flange and sidewall, angle between sidewall and part bottom, chamfer radius between part bottom and sidewall or chamfer radius between sidewall and flange are recorded in a data base. The initial simulations plan together with the generated data base is used as an input for the genetic algorithm optimization method. With the optimized process parameters a new simulation is made and the final shape of the part is compared with the ideal geometry. The shape of the part obtained with the optimized parameters is proving the capability of the proposed method.

Identification of Selective Norbornane-Type Aspartate Analogue Inhibitors of the Glutamate Transporter 1 (GLT-1) from the Chemical Universe Generated Database (GDB)

A variety of conformationally constrained aspartate and glutamate analogues inhibit the glutamate transporter 1 (GLT-1, also known as EAAT2). To expand the search for such analogues, a virtual library of aliphatic aspartate and glutamate analogues was generated starting from the chemical universe database GDB-11, which contains 26.4 million possible molecules up to 11 atoms of C, N, O, F, resulting in 101026 aspartate analogues and 151285 glutamate analogues. Virtual screening was realized by high-throughput docking to the glutamate binding site of the glutamate transporter homologue from Pyrococcus horikoshii (PDB code: 1XFH ) using Autodock. Norbornane-type aspartate analogues were selected from the top-scoring virtual hits and synthesized. Testing and optimization led to the identification of (1R*,2R*,3S*,4R*,6R*)-2-amino-6-phenethyl-bicyclo[2.2.1]heptane-2,3-dicarboxylic acid as a new inhibitor of GLT-1 with IC(50) = 1.4 μM against GLT-1 and no inhibition of the related transporter EAAC1. The systematic diversification of known ligands by enumeration with help of GDB followed by virtual screening, synthesis, and testing as exemplified here provides a general strategy for drug discovery.

Embryos frozen at the 2PN stage demonstrate a reduced number of cells at the third day compared with fresh embryos of the same cycles

Objective: To determine the cleavage potential of three-day embryos that were frozen at the 2PN stage, compared with embryos from the corresponding fresh cycles.Design: Retrospective computer generated data base study.Materials and Methods: Embryos from 248 fresh IVF cycles and their corresponding 344 freeze-thaw cycles were analyzed using our computerized data base. Eighteen hours after in-vitro fertilization, embryos were examined and determined to be at a 2PN stage. At that time embryos were either left to continue incubation (fresh cycle) of frozen (freeze-thaw cycle). Seventy-two hours after fertilization in the “fresh cycle” or 48 hours after the thaw in freeze cycles the degree of cleavage was determined according to the number of blastomers in each embryo. This information was recorded in our computer database. We retrospectively compared the cleavage degree of embryos from the “fresh cycle” with the “freeze-thaw cycle” embryos according to their blastomer number: from 2 cells to the morula stage.Results: The fraction of embryos with a lower degree of cleavage (2–3 blastomer embryos) was significantly higher in the “freeze-thaw” cycles being 10.06% of the embryos compared with 5.1% in the “fresh” cycle (p<0.001 by Fisher’s exact test). Additionally, the fraction of higher degree cleavage embryos (8 balstomers-morula) was significantly lower in the “freeze-thaw” cycles being 34.95% of the embryos compared with 45.41% in the “fresh” cycle (p<0.001)Conclusion: We demonstrated that following a “freeze-thaw” cycle the degree of embryo cleavage is reduced significantly compared with fresh cycles. Objective: To determine the cleavage potential of three-day embryos that were frozen at the 2PN stage, compared with embryos from the corresponding fresh cycles. Design: Retrospective computer generated data base study. Materials and Methods: Embryos from 248 fresh IVF cycles and their corresponding 344 freeze-thaw cycles were analyzed using our computerized data base. Eighteen hours after in-vitro fertilization, embryos were examined and determined to be at a 2PN stage. At that time embryos were either left to continue incubation (fresh cycle) of frozen (freeze-thaw cycle). Seventy-two hours after fertilization in the “fresh cycle” or 48 hours after the thaw in freeze cycles the degree of cleavage was determined according to the number of blastomers in each embryo. This information was recorded in our computer database. We retrospectively compared the cleavage degree of embryos from the “fresh cycle” with the “freeze-thaw cycle” embryos according to their blastomer number: from 2 cells to the morula stage. Results: The fraction of embryos with a lower degree of cleavage (2–3 blastomer embryos) was significantly higher in the “freeze-thaw” cycles being 10.06% of the embryos compared with 5.1% in the “fresh” cycle (p<0.001 by Fisher’s exact test). Additionally, the fraction of higher degree cleavage embryos (8 balstomers-morula) was significantly lower in the “freeze-thaw” cycles being 34.95% of the embryos compared with 45.41% in the “fresh” cycle (p<0.001) Conclusion: We demonstrated that following a “freeze-thaw” cycle the degree of embryo cleavage is reduced significantly compared with fresh cycles.

Intelligent picking of chaotically stored objects

A robot system for the intelligent picking of chaotically stored objects by the analysis of depth data is presented in this research article. This “bin‐picking” enables the automatic storing of objects which is a prerequisite for the automatic supply of a processing machine. In order to improve conventional localization systems, special attention is paid – apart from the identification of object positions – to gripping point calculation for the picking and to collision avoidance. To adapt the system to different object geometries, an approach that aims at storing the necessary object data in an off‐line generated data base was chosen.

RECONSTRUCTING PHYSICAL VARIABLES AND PARAMETERS FROM DYNAMICAL SYSTEMS

Variables and parameters of a dynamical system are recovered from a previously generated data base using the time delay reconstruction of states from a single observable. This method may be used for efficiently monitoring variables or parameters of technical systems that are difficult to access. Its application to an electronic oscillator is demonstrated experimentally.

The variability of low building wind loads due to surrounding obstructions

Most low buildings are sutuated in urban areas in the midst of neighbouring buildings, trees, fences, billboards and parks. These cluttered, undisciplined surroundings can have as much effect on the wind loads as do the details of the geometry of the building itself and often even more so. Studies in recent years have focussed primarily on the influence of turbulent boundary layer winds in open terrain relatively free of surrounding obstructions in which building geometry is a dominant factor. In this study, a new approach is proposed to study the interference of local obstructions on low building wind loads from a statistical point of view through wind tunnel experiments. An experimental wind tunnel simulation with randomized wind load parameters, especially random surroundings, is proposed. The generated data base, together with data from other relevant studies, can form the basis for a reliability analysis to predict wind loads for design codes. This paper outlines this approach and reports the exploratory tests on the effects of surroundings on area and local wind loads. The results show that wind loads in a realistic environment do not always follow the basic wind load characteristics of an isolated building because of interference by neighbouring buildings. The variation of wind loads with wind direction is less severe while the variability due to building location is large. Since expected values are considerably less than the ‘worst case’ data from isolated building tests, these results raise questions concerning the traditional approaches to choosing design loads.

The variability of low building wind loads due to surrounding obstructions

Most low buildings are sutuated in urban areas in the midst of neighbouring buildings, trees, fences, billboards and parks. These cluttered, undisciplined surroundings can have as much effect on the wind loads as do the details of the geometry of the building itself and often even more so.Studies in recent years have focussed primarily on the influence of turbulent boundary layer winds in open terrain relatively free of surrounding obstructions in which building geometry is a dominant factor. In this study, a new approach is proposed to study the interference of local obstructions on low building wind loads from a statistical point of view through wind tunnel experiments. An experimental wind tunnel simulation with randomized wind load parameters, especially random surroundings, is proposed. The generated data base, together with data from other relevant studies, can form the basis for a reliability analysis to predict wind loads for design codes.This paper outlines this approach and reports the exploratory tests on the effects of surroundings on area and local wind loads. The results show that wind loads in a realistic environment do not always follow the basic wind load characteristics of an isolated building because of interference by neighbouring buildings. The variation of wind loads with wind direction is less severe while the variability due to building location is large. Since expected values are considerably less than the ‘worst case’ data from isolated building tests, these results raise questions concerning the traditional approaches to choosing design loads.

A language for inquiring about the run‐time behaviour of programs

AbstractThis paper describes a language for studying the behaviour of programs, based upon the data collected while these programs are executed by a computer. Besides being a useful tool in debugging, the language is also valuable in the experimental evaluation of the complexity of algorithms, in studying the interdependence of conditionals in a program and in determining the feasibility of transporting programs from one machine to another. The program one wishes to analyse is written in an Algol 60‐like language; when the program is executed it automatically stores, in a data base, the information needed to answer general questions about computational events which occurred during execution. This information consists (basically) of the list of labels passed while the program is being executed, and the current values of the variables. Since the list of labels is describable by regular expressions, these expressions can also be used to identify specific subparts of the list and therefore allow access to the values of the variables. This constitutes the basis for the design of the inquiry language. The user's questions are automatically answered by a processor which inspects the previously generated data base. The paper also presents examples of the use of the language and describes the implementation of its processor.

A Simulative Study of Correlated Error Propagation in Various Finite-Precision Arithmetics

The accumulated roundoff error incurred in long arithmetic computations involving a randomized mixture of addition, subtraction, multiplication, and division operations applied to an initial randomly generated data base is studied via simulation. Truncated and rounded floating-point arithmetic and truncated and rounded logarithmic arithmetic are simultaneously utilized for each of the computation sequences and the resulting roundoff error accumulations for these four systems are compared. The nature of the correlated errors incurred under various arithmetic operator mixes are discussed.