WIN-EC: An Electronic Commerce Model for Small Business

The accessibility of the Internet and the World Wide Web has provided an excellent means for presenting, disseminating and distributing information. As well, this is a new and convenient channel for businesses to reach customers and other businesses. In this paper, we describe WIN-EC, an electronic commerce model for small business. We discuss various services that a typical small business may want to provide its customers. Possible technologies to implement the services are examined and finally, a prototype to generate such a model will be suggested

An improvement of non-integrated defect relation for meromorphic maps from Kahler manifolds with arbitrary hypersurfaces

Our purpose in this paper is to establish a non-integrated defect relation for meromorphic mappings from a complete Kahler manifold into a projective variety intersecting an arbitrary family of hypersurfaces with explicit truncation level. In our result, both the above bound of the total defect and the truncation level are estimated independently of the number of involving hypersurfaces. Our result generalizes and improves the previous results in this topic.Comment: 15 pages. arXiv admin note: text overlap with arXiv:1712.0569

Self-Centering Prestressed Concrete Pier Considering the Effect of Vertical Earthquake Motions with External Aluminum Dissipators

A prototype self-centering prestressed concrete (SCPC) bridge pier and conventional reinforced concrete (RC) pier with similar backbone curves are designed and modeled. The objective of this study is to investigate the seismic performance of the SCPC bridge pier considering the effect of vertical earthquake ground motions. Under a severe vertical earthquake motion, the RC pier damage is much greater than the SCPC pier. The SCPC bridge pier shows a great capability in reducing residual drift at the top of the structure, therefore, the probability of bridge survival is increased. In this study, the external aluminum bars were used to reduce the seismic energy impacts on the bridge pier structure. In addition, The averages of the maximum and residual drifts of bridge piers under a set of 20 earthquake ground motion records impact with different vertical-to-horizontal peak acceleration ratios on the bridge seismic response are presented. The results are compared with the case of horizontal-only excitations, to clarify the effect of the vertical earthquake on the SCPC and RC bridge pier. Hence, the designers can find good solutions for structures in earthquakes resistance

COMMUTERS' EXPOSURE TO PARTICULATE MATTER AND CARBON MONOXIDE IN HANOI : A PILOT STUDY

Joint Research on Environmental Science and Technology for the Eart

Weak Lefschetz property of graded Gorenstein algebras associated to the Apéry set of a numerical semigroup

It has been conjectured that all graded Artinian Gorenstein algebras of codimension three have the weak Lefschetz property over a field of characteristic zero. In this paper, we study the weak Lefschetz property of associated graded algebras A of the Apéry set of M-pure symmetric numerical semigroups generated by four natural numbers. These algebras are graded Artinian Gorenstein algebras of codimension three

Noncontact sensing systems and autonomous decision-making for early-age concrete

Early-age cracking and spalling in concrete pavements reduces slab capacity, joint load transfer, ride quality, and its long-term performance. These premature distresses lead to increased maintenance costs for sealing, patching, and grinding. Proper timing of sawcutting and curing are two construction activities that can minimize early-age distress development. In order to better time sawcutting and curing activities, an improved method to spatially monitor the setting time of concrete is required. Likewise, rapid evaluation of the joint quality after sawing is also necessary to provide feedback to adjust the timing. While previous methods for sawcutting and curing are experiential and subjective, this research aims to develop contactless sensing and computer vision techniques to significantly improve the timing of certain early-age concrete construction activity decisions through quantitative indicators. A non-contact, ultrasonic testing system (UTS) to monitor concrete set time has been developed by monitoring the evolution of leaky Rayleigh (LR-wave) wave signals over time and space (surface of the concrete). The non-contact UTS integrates a 50 kHz non-contact ultrasonic transmitter and an array of five microelectromechanical systems (MEMS) sensors as non-contact receivers. The UTS technique was first implemented in the laboratory at incident angles of 12^° for mortar mixtures in order to determine the final setting times. The UTS technique was also applied at different incident angles (12^° to 60^° ) on a mortar mixture to evaluate its influence of the angle on the UTS measurement. The final setting times for mortars were consistent with the ASTM C403 penetration resistance standard when an incident angle of 12^° was used. Additionally, this UTS was successfully field validated on three concrete pavement test sections in Illinois that had different casting times during the day. Final setting times in the field greatly varied (287 to 210 minutes) given the higher ambient temperatures and surrounding concrete mass. In order to improve decision-making on sawcut timing, the final set times measured by the UTS were linked with the earliest time to initiate sawcutting within an acceptable level of raveling. A computer vision-based (CV) process was developed that employed multiple joint images, 2D segmentation for joint raveling/spalling extraction, 3D point cloud reconstruction and meshing of the joint damage, and a 3D damage quantification analysis for assessing the joint damage. The proposed CV-based joint damage analysis quantified joint damage through two newly defined indices: (i) raveling damage index (RDI) for raveling and (ii) joint damage index (JDI) for spalling. The proposed CV-based method had an accuracy of 76% with an error of 10%. With this CV-based process, it was determined that RDI of 3% or less is an acceptable quality level for contraction joints in the field. A one-sided multi-sensor ultrasonic array device with a support vector machine algorithm was developed that detects the existence of a concealed, vertical crack beneath a notched contraction joint. This algorithm supports the field assessment of the effectiveness of sawcut timing, sawcut depth, and whether premature slab cracking was related to poor sawing procedures. The multi-sensor ultrasonic array device generated and received ultrasonic shear waves (S-wave) across the inspected joint. The acquired time domain signals were used to calculate normalized transmission energy (NTE) across the joint. The NTE algorithm defined the ratio of the energy of diffracted and reflected S-waves received behind the joint with respect to the energy of direct, diffracted, and reflected S-waves received in front of the joint. Laboratory results demonstrated that the NTE technique could successfully identify the existence or non-existence of a crack beneath the sawcut. Finally, the NTE technique coupled with a 2D decision boundary equation was field validated on 152 concrete pavement contraction joints from multiple projects with similar slab thicknesses and sawcut notch depths in Illinois and Iowa. Finally, the non-contact UTS was coupled with a 2D wavefield analysis to rapidly evaluate the effectiveness, spatially and with time, of curing methods through monitoring of the near-surface damage in hydrating paste at early-ages. The new technique monitored the energy of the LR-waves signal over time with the non-contact UTS and then, analyzed the frequency-wave number (f-k) domain to characterize the quantity of near-surface damage in the cement paste specimens. An ultrasonic surface damage index (USDI) was defined from the f-k wavefield domain based on the ratio of the non-propagating and forwarding LR-wave energy. The non-contact sensing and 2D wavefield analysis easily distinguished the differences in surface damage between the different curing methods (no curing surface, the plastic sheet cover cure, and the wax-based curing). Surfaces with low surface damage had negligible non-propagating wave energy, which was seen in the wax-based curing specimens and the unexposed bottom surfaces of all cast specimens

Predicting Agricultural Commodities Prices with Machine Learning: A Review of Current Research

Agricultural price prediction is crucial for farmers, policymakers, and other stakeholders in the agricultural sector. However, it is a challenging task due to the complex and dynamic nature of agricultural markets. Machine learning algorithms have the potential to revolutionize agricultural price prediction by improving accuracy, real-time prediction, customization, and integration. This paper reviews recent research on machine learning algorithms for agricultural price prediction. We discuss the importance of agriculture in developing countries and the problems associated with crop price falls. We then identify the challenges of predicting agricultural prices and highlight how machine learning algorithms can support better prediction. Next, we present a comprehensive analysis of recent research, discussing the strengths and weaknesses of various machine learning techniques. We conclude that machine learning has the potential to revolutionize agricultural price prediction, but further research is essential to address the limitations and challenges associated with this approach

Effect of phosphate fertilizer-coated Dicarboxylic Acid Polymer on rice yield and components under greenhouse conditions

A significant amount of phosphorus (P) becomes fixed by aluminium (Al) and iron (Fe) in acidic soils, leading to decreased efficiency in P utilization and subsequently lowering crop yield. Enhanced P fertilization offers a potential solution, as the dicarboxylic acid polymer (DCAP) coating on P fertilizer promotes increased plant productivity and more effective P utilization. The improvement achieved through enhanced P fertilization can contribute to higher rice yields in acidic soils, accompanied by an increase in P solubility. The study aimed to determine the impact of DCAP-mixed phosphate fertilizer on P uptake by plants, absorption efficiency, and rice yield. The results demonstrated a significant increase in available P (about 3.5 mg P/kg) when DCAP was used in a greenhouse setting, resulting in elevated yields and total P absorption (ranging from 0.03 to 0.05 grams/pot). However, the addition of 60 kg of phosphate mixed with DCAP has not yet demonstrated a significant increase in available phosphorus in the soil compared to adding just 60 kg of phosphate. The application of phosphate at a dose of 30 kg of P2O5 mixed with DCAP for growth and phosphorus absorption yield results equivalent to using 60 kg of P2O5 without DCAP. Furthermore, the use of DCAP in conjuction with 50% P fertilizer increased P availability by the same amount as that achieved with 100% P fertilizer. Consequently, DCAP reduced chemical P fertilizer in the soil by approximately 50%. However, it is essential to evaluate the effectiveness of mixed phosphate fertilizer (DCAP) under field conditions before recommending its widespread use