Enhancing Heat Transfer in Internal Combustion Engine by Applying Nanofluids

Nanofluids exhibit novel properties including significant heat transfer properties that make them potentially useful in internal combustion engine cooling. However, although there is a substantial number of mechanisms proposed, modeling works related to their enhanced thermal conductivity, systematic mechanisms, or models that are suitable for nanofluids are still lacked. With molecular dynamics simulations, thermal conductivities of nanofluids with various nanoparticles have been calculated. Influence rule of various factors for thermal conductivity of nanofluids has been studied. Through defining the ratio of thermal conductivity enhancement by nanoparticle volume fraction, Κ, the impacts of nanoparticle properties for thermal conductivity are further evaluated. Furthermore, the ratio of energetic atoms in nanoparticles, E, is proposed to be an effective criterion for judging the impact of nanoparticles for the thermal conductivity of nanofluids. Mechanisms of heat conduction enhancement are investigated by MD simulations. Altered microstructure and movements of nanoparticles in the base fluid are proposed to be the main reasons for thermal conductivity enhancement in nanofluids. Both the static and dynamic mechanisms for heat conduction enhancement in nanofluids have been considered to establish a prediction model for thermal conductivity. The prediction results of the present model are in good agreement with experimental results

Sound Velocity Profile (SVP) inversion through correcting the terrain distortion

In this paper, mode vectors are obtained via the Empirical Orthogonal Function (EOF) based on real Sound Velocity Profiles (SVP) measurements. Through correcting the terrain distortion, reconstructed coefficients of SVPs are determined by Genetic Algorithm (GA) and then the inversion result of the SVP is obtained. The conclusions show that the terrain distortion caused by sound velocity errors can be effectively corrected by the inversion result of the SVP. Using this process, the accuracy and processing efficiency of multi-beam bathymetry data can be significantly improved.En este artículo, se obtienen los vectores de forma a través de la Función Empírica Ortogonal (EOF) basada en mediciones reales de los Perfiles de la Velocidad del Sonido (SVP). Mediante la corrección de la distorsión del terreno, los coeficientes reconstruidos de los SVPs son determinados por el Algoritmo Genético (AG) y posteriormente se obtiene el resultado de la inversión del SVP. Las conclusiones muestran que la distorsión del terreno causada por errores de velocidad del sonido puede corregirse eficazmente mediante el resultado de la inversión del SVP. Utilizando este proceso, la exactitud y la eficiencia del procesado de los datos de batimetría multihaz pueden mejorarse significativamente.Cet article décrit la décomposition en vecteurs propres via les fonctions empiriques orthogonales (EOF) des mesures des profils de vitesse du son (SVP). La correction des distorsions de terrain permet de déterminer des coefficients reconstruits des SVP à l’aide d’un algorithme génétique (AG), puis le résultat de l’inversion du SVP est obtenu. Les conclusions montrent que les distorsions de terrain causées par les erreurs de vitesse du son peuvent être effectivement corrigées par le résultat de l’inversion du SVP. A l’aide de ce processus, la précision et l’efficacité du traitement des données bathymétriques multifaisceaux peuvent être améliorées de façon importante

Research on the Design of Survery Lines in a Marine Magnetic Survey

The planning of a marine magnetic survey requires careful consideration in the design of the survey lines to ensure the results of the survey meet expected standards. This paper describes various evaluation methods to determine an optimal survey line layout for a marine magnetic survey that conforms to Chinese marine magnetic survey Standards. Various survey line layouts are tested using simulated data to evaluate the interpolation precision between neighbouring survey lines and the magnetic anomaly map. The test results provide a recommended process to determine the rationality and the optimal layout of the survey line pattern for undertaking marine magnetic surveys.La planificación de un levantamiento magnético marino requiere una cuidadosa consideración en el diseño de las trayectorias a seguir para garantizar que los resultados del levantamiento cumplan las normas esperadas. Este artículo describe los diversos métodos de evaluación para determinar una disposición óptima de las trayectorias para un levantamiento magnético marino que sea conforme a las normas chinas de levantamientos magnéticos marinos. Se han efectuado pruebas sobre varias disposiciones de trayectorias, utilizando datos simulados para evaluar la precisión de la interpolación entre trayectorias vecinas y el mapa de anomalías magnéticas. Los resultados de las pruebas proporcionan un proceso recomendado para determinar la racionalidad y la disposición óptima del patrón de trayectorias para llevar cabo levantamientos magnéticos marinos.La planification d’un levé magnétique marin requiert un examen minutieux de la conception des profils de sonde pour assurer que les résultats du levé répondent aux normes attendues. Cet article décrit différentes méthodes d’évaluation en vue de déterminer une présentation de profil de sonde optimale pour un levé magnétique marin qui soit conforme aux normes des levés magnétiques marins chinois. Diverses présentations de profils de sonde sont testées à l’aide de données simulées dans le but d’évaluer la précision de l’interpolation entre profils de sonde voisins et la carte des anomalies magnétiques Les résultats des tests permettent de recommander un processus pour déterminer la rationalité et la présentation optimale du schéma de profil de sonde afin d’entreprendre des levés magnétiques marins

The Short Text Matching Model Enhanced with Knowledge via Contrastive Learning

In recent years, short Text Matching tasks have been widely applied in the fields ofadvertising search and recommendation. The difficulty lies in the lack of semantic information and word ambiguity caused by the short length of the text. Previous works have introduced complement sentences or knowledge bases to provide additional feature information. However, these methods have not fully interacted between the original sentence and the complement sentence, and have not considered the noise issue that may arise from the introduction of external knowledge bases. Therefore, this paper proposes a short Text Matching model that combines contrastive learning and external knowledge. The model uses a generative model to generate corresponding complement sentences and uses the contrastive learning method to guide the model to obtain more semantically meaningful encoding of the original sentence. In addition, to avoid noise, we use keywords as the main semantics of the original sentence to retrieve corresponding knowledge words in the knowledge base, and construct a knowledge graph. The graph encoding model is used to integrate the knowledge base information into the model. Our designed model achieves state-of-the-art performance on two publicly available Chinese Text Matching datasets, demonstrating the effectiveness of our model.Comment: 11 pages,2 figure

Chromatin Dynamics: Chromatin Remodeler, Epigenetic Modification and Diseases

The gene transcription patterns are regulated in response to extracellular stimuli and intracellular development programs. Recent studies have shown that chromatin dynamics which include nucleosome dynamics and histone modification play a crucial role in gene expression. Chromatin dynamic is regulated by chromatin modification enzymes including chromatin remodeling complex and histone posttranslational modifications. Multiple studies have shown that chromatin dynamics dysregulation and aberrant and histone modifications resulted in the occurrence of various diseases and cancers. Moreover, frequent mutations and chromosomal aberrations in the genes associated with subunits of the chromatin remodeling complexes have been detected in various cancer types. In this review, we highlight the current understanding of orchestration of nucleosome position, histone modification, and the importance of these properly regulated dynamics. We also discuss the consequences of aberrant chromatin dynamic which results in disease progression and provides insights for potential clinic applications

Topological Embedding Feature Based Resource Allocation in Network Virtualization

Virtualization provides a powerful way to run multiple virtual networks on a shared substrate network, which needs accurate and efficient mathematical models. Virtual network embedding is a challenge in network virtualization. In this paper, considering the degree of convergence when mapping a virtual network onto substrate network, we propose a new embedding algorithm based on topology mapping convergence-degree. Convergence-degree means the adjacent degree of virtual network's nodes when they are mapped onto a substrate network. The contributions of our method are as below. Firstly, we map virtual nodes onto the substrate nodes with the maximum convergence-degree. The simulation results show that our proposed algorithm largely enhances the network utilization efficiency and decreases the complexity of the embedding problem. Secondly, we define the load balance rate to reflect the load balance of substrate links. The simulation results show our proposed algorithm achieves better load balance. Finally, based on the feature of star topology, we further improve our embedding algorithm and make it suitable for application in the star topology. The test result shows it gets better performance than previous works

Pathway and kinetics of cyhalothrin biodegradation by Bacillus thuringiensis strain ZS-19

10.1038/srep08784Scientific Reports

Layer-by-Layer Assembly and Photocatalytic Activity of Titania Nanosheets on Coal Fly Ash Microspheres

In order to address the problem with titania distribution and recovery, series of Ti0.91O2/CFA photocatalysts (Ti0.91O2/CFA-n, n=2,4,6, and 8) were fabricated by assembling Ti0.91O2 nanosheets on coal fly ash (CFA) microspheres via the layer-by-layer assembly (LBLA) process and characterized by scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), N2-sorption, and ultraviolet-visible absorption (UV-vis) techniques. The SEM images and UV-vis spectra illustrated that Ti0.91O2 nanosheets were immobilized successfully on the CFA by the LBLA approach and changed the characteristics of CFA noticeably. The photocatalytic activity of Ti0.91O2/CFA was evaluated by the photodegradation of methylene blue (MB) under UV irradiation. The results demonstrated that Ti0.91O2/CFA-6 showed the best photocatalytic activity among the series of Ti0.91O2/CFA irradiated for 60 min, with a decoloration rate above 43%. After photocatalysis, the Ti0.91O2/CFA could be easily separated and recycled from aqueous solution and Ti0.91O2 nanosheets were still anchored on the CFA