Effect of the Arrangement of a New-Type of Turbulator Inserts on Heat Pipe Exchanger Performances

This research tests the effect of introducing turbulators of a new type into a circular tube heat exchanger under a constant and uniform longitudinal heatflux condition.A 45 mm diameter copper tube with a length of 1,350 mm is utilized with a solid disk being inserted inside the tube,which consists of three sections,each one containing two slots.The slot is cut at a 45 degree angle toward the inner tube surface,which results in diverging theflow toward the inner hot tube surface in order to enhance the heat transfer process.Air is considered as the workingfluid with Prandtl number 0.71.The Reynolds number spans the interval from 6,000–13,500,which indicates that the consideredflow is turbulent.The heat exchanger performance is studied and analyzed in terms of average Nusselt number.The experimental results show that the Nusselt number value is directly proportional to the increase of the Reynolds number,and the number of turbulators inserts.With the use of three novel turbulators,the heat transfer was about 3.15 times higher than that in the smooth tube and the friction factor was about 1.11.

Ore Texture,Mineralogy and Whole Rock Geochemistry of the Iron Mineralization from Edea North Area,Nyong Complex,Southern Cameroon:Implication for Origin and Enrichment Process

This study presents the ore texture, mineralogy and whole rock geochemistry of iron occurrence from the Edea North area located at the upper limit of the Nyong Unit, part of the Congo craton. This iron mineralization is of magnetite quartzite type enclosed by metamorphic rocks of the granulite facies. Two main facies have been identified over the study area including the banded and the massive facies. The mineralogical set of these facies is in majority represented by magnetite, quartz and pyroxene martite in addition to minor biotite, apatite, and amphibole. Magnetite presents as irregular and elongated minerals which can contain quartz inclusions of various shapes and sizes, as blasts clustering, around pyroxenes and isolated xenomorphic magnetite minerals in the silicate phases. Quartz varies from fine to coarse-grained and ribbon quartz. This indicates re-crystallization and deformation during metamorphism. Electron microprobe analysis on magnetite and martite show Fe2O3 contents that vary between 96.11 and 99.76. Whole rock chemical data showed that Fe-contents are as high as 62.9 wt%. The SiO2 content varies between 33.8 wt% and 51.2 wt%. Iron oxides and SiO2 are negatively correlated. Moreover, the low positive correlations between Al2O3 and HFSE, and LILE suggest a contribution of clastic materials in the protolith of studied materials. The samples show low contents of V, Cr, Ba, Zr with respect to igneous rocks. This may infer a sedimentary origin for the studied rocks;furthermore, these materials may have undergone hydrothermal alteration. The REE patterns reveal enrichment in LREE compared to HREE. Some samples show positive Eu (1.82) and other negative anomalies Eu (0.54 to 0.97). The lack of Ce anomalies suggests that the depositional environment of the Edea North iron occurrence was anoxic or suboxic. Overall, the Edea North iron occurrence may have undergone significant input from hydrothermal sources with imprints of the clastic during its deposition.

Hydrothermal Alteration of Basaltic Rocks at Eruptive Vents on Mount Cameroon Volcano, West Africa

The study of changes in rocks due to interaction with hydrothermal fluids at active volcanoes provides insights into wall rock alteration associated with ore deposits formed in the geological past. Therefore, the nature of mineral alteration and chemical changes experienced by wall rocks can be investigated at eruptive sites on active volcanoes and the results used to better constrain ore-forming processes. In this study, we investigated the alteration at eruptive sites at Mount Cameroon volcano. These eruptive vents lie along NE-SW-trending fissures that define the Mount Cameroon rift. The vents are surrounded by cones composed largely of pyroclastic materials and to a lesser extent lava. Fumaroles (volcanic gases) rising through the vents during and after the 1999 eruption have resulted in the alteration of the pyroclastic robble along the fissures and the inner walls of the cones. Consequently, altered basaltic materials are covered with thin films of reddish, yellowish to whitish secondary minerals. These coatings result from an interaction between the surfaces of the basaltic glass with volcanically-derived acidic fluids. Petrographic investigations and XRD analysis of the basalts have identified primary mineral phases, such as olivine, pyroxene (mainly augite) and feldspars. Alteration products revealed include ubiquitous silica as well as gypsum, magnetite, feldspar, alunite and jarosite. Jarosite occurrence indicates that SO2 is the primary volcanically-derived acid source involved in coating formation. High contents of sulfur identified in the basalts indicate that melts at Mount Cameroon can be sulfur saturated as backed by previous melt inclusion data. Whole rock geochemical analysis shows a gain in silica in the altered samples and this ties with the mass balance calculations although minor gains of Al2O3, , MgO, MnO, CaO and K2O are shown by some samples.

Price Prediction of Seasonal Items Using Time Series Analysis

The price prediction task is a well-studied problem due to its impact on the business domain.There are several research studies that have been conducted to predict the future price of items by capturing the patterns of price change,but there is very limited work to study the price prediction of seasonal goods(e.g.,Christmas gifts).Seasonal items’prices have different patterns than normal items;this can be linked to the offers and discounted prices of seasonal items.This lack of research studies motivates the current work to investigate the problem of seasonal items’prices as a time series task.We proposed utilizing two different approaches to address this problem,namely,1)machine learning(ML)-based models and 2)deep learning(DL)-based models.Thus,this research tuned a set of well-known predictive models on a real-life dataset.Those models are ensemble learning-based models,random forest,Ridge,Lasso,and Linear regression.Moreover,two new DL architectures based on gated recurrent unit(GRU)and long short-term memory(LSTM)models are proposed.Then,the performance of the utilized ensemble learning and classic ML models are compared against the proposed two DL architectures on different accuracy metrics,where the evaluation includes both numerical and visual comparisons of the examined models.The obtained results show that the ensemble learning models outperformed the classic machine learning-based models(e.g.,linear regression and random forest)and the DL-based models.

Enhancing IoT Data Security with Lightweight Blockchain and Okamoto Uchiyama Homomorphic Encryption

Blockchain technology has garnered significant attention from global organizations and researchers due to its potential as a solution for centralized system challenges.Concurrently,the Internet of Things(IoT)has revolutionized the Fourth Industrial Revolution by enabling interconnected devices to offer innovative services,ultimately enhancing human lives.This paper presents a new approach utilizing lightweight blockchain technology,effectively reducing the computational burden typically associated with conventional blockchain systems.By integrating this lightweight blockchain with IoT systems,substantial reductions in implementation time and computational complexity can be achieved.Moreover,the paper proposes the utilization of the Okamoto Uchiyama encryption algorithm,renowned for its homomorphic characteristics,to reinforce the privacy and security of IoT-generated data.The integration of homomorphic encryption and blockchain technology establishes a secure and decentralized platformfor storing and analyzing sensitive data of the supply chain data.This platformfacilitates the development of some business models and empowers decentralized applications to perform computations on encrypted data while maintaining data privacy.The results validate the robust security of the proposed system,comparable to standard blockchain implementations,leveraging the distinctive homomorphic attributes of the Okamoto Uchiyama algorithm and the lightweight blockchain paradigm.

Oxidation Properties in CO_2 of Inconel Alloy 600 Coated by Simultaneous Aluminizing-Chromizing Process

IN 600 alloy was coated with two different types of coatings, Cr-modified aluminide coating this is called aluminizing-chromizing and Y-doped chromium modified aluminide coating this is called aluminizing-chromizing-yttriumizing. Diffusion coating was carried at 1 050℃ for 8 h under Ar atmosphere by simultaneous aluminizing-chromizing process and by simultaneous aluminizing-chromizing- yttriumizing. Cyclic oxidation tests were conducted on the uncoated and on the coated Inconel 600 alloy in the temperature range 800- 1 000℃ in CO2 for 100 h at 10 h cycle.The results showed that the oxidation kinetics for uncoated Inconel 600 alloy in CO2 is parabolic and the phases present are NiO, （Fe, Cr）2O3 , NiFe2O4 and NiCrO4. The oxidation kinetics for both coated systems in CO2 was found to be parabolic and the value ofkp for both coated systems were found to be lower than that for uncoated Inconel 600 alloy. Oxide phases that formed on coated systems are Al2O3 and NiCrO4. The role of yttrium can be attributed to its ability to improve the adherence of the oxide scale.

Experimental and numerical studies of the blast-induced overbreak and underbreak in underground roadways

Overbreak and underbreak are the crucial problems during the blasting excavation of underground tunnels owing to their effects on the construction costs and operational safety.A critical challenge facing overbreak and underbreak control is the difficulty in developing guidelines with respect to various and complex engineering conditions.In this study,a series of field measurements of overbreak and underbreak using the Focus^(S)150 laser scanner were performed in a deep roadway of the Kaiyang phosphate mine,China.The distri-bution and extent of the overbreak and underbreak surrounding the roadway contour were accurately analyzed in accordance with the collected point cloud data.Subsequently,a simplified three-dimensional model was established to simulate the blasting excavation of pre-stressed roadway using the explicit dynamic analysis code LS-DYNA.A comparison of numerical and measurement results revealed that the proposed model was a reliable tool to simulate the overbreak and underbreak induced by blasting excavation.Thereafter,the influ-ences of uncontrollable geological factors such as in situ stress conditions and controllable blasting factors including contour hole spac-ing(S),charge concentration(b)and decoupled coefficient(f)as well as stemming were further numerically investigated.The simulation results indicated that the lateral pressure coefficient significantly affected the distribution pattern of the overbreak and underbreak,while the stress magnitude contributed to their extents.Moreover,a comparison of the simulation findings and the field measurement data indicated that the minimal extents of the overbreak and underbreak corresponding the optimal contour blasting results were obtained at S=0.70 m,b=0.9 kg/m and f=2.5,respectively.Furthermore,the contour blastholes stemmed with sand created smaller damage to the periphery rock mass of roadway and enhanced the utilization efficiency of explosive energy.The research findings of this study pro-vide important implications for similar blasting excavation projects.

Enhanced Metaheuristics with Trust Aware Route Selection for Wireless Sensor Networks

Recently,a trust system was introduced to enhance security and cooperation between nodes in wireless sensor networks(WSN).In routing,the trust system includes or avoids nodes related to the estimated trust values in the routing function.This article introduces Enhanced Metaheuristics with Trust Aware Secure Route Selection Protocol(EMTA-SRSP)for WSN.The presented EMTA-SRSP technique majorly involves the optimal selection of routes in WSN.To accomplish this,the EMTA-SRSP technique involves the design of an oppositional Aquila optimization algorithm to choose safe routes for data communication.For the clustering process,the nodes with maximum residual energy will be considered cluster heads(CHs).In addition,the OAOA technique gets executed to choose optimal routes based on objective functions with multiple parameters such as energy,distance,and trust degree.The experimental validation of the EMTA-SRSP technique is tested,and the results exhibited a better performance of the EMTA-SRSP technique over other approaches.

Progressive LiDAR Adaptation for Road Detection

Despite rapid developments in visual image-based road detection, robustly identifying road areas in visual images remains challenging due to issues like illumination changes and blurry images. To this end, LiDAR sensor data can be incorporated to improve the visual image-based road detection,because LiDAR data is less susceptible to visual noises. However,the main difficulty in introducing LiDAR information into visual image-based road detection is that LiDAR data and its extracted features do not share the same space with the visual data and visual features. Such gaps in spaces may limit the benefits of LiDAR information for road detection. To overcome this issue, we introduce a novel Progressive LiDAR adaptation-aided road detection(PLARD) approach to adapt LiDAR information into visual image-based road detection and improve detection performance. In PLARD, progressive LiDAR adaptation consists of two subsequent modules: 1) data space adaptation, which transforms the LiDAR data to the visual data space to align with the perspective view by applying altitude difference-based transformation; and 2) feature space adaptation, which adapts LiDAR features to visual features through a cascaded fusion structure. Comprehensive empirical studies on the well-known KITTI road detection benchmark demonstrate that PLARD takes advantage of both the visual and LiDAR information, achieving much more robust road detection even in challenging urban scenes. In particular, PLARD outperforms other state-of-theart road detection models and is currently top of the publicly accessible benchmark leader-board.

一个新的中医研究范式:从非线性动力学的角度解读中医

西方对中医的研究多是利用随机控制试验来检验其疗效。通过讨论,认为这类研究有其局限性。同时探讨一种新的研究范式,即非线性动力学理论。认为这一理论能够提供理论依据来设计适合中医特征的临床试验,并可望得出为西方医学界所接受的研究结果。

SELECTED PAPERS FROM IEEE/CIC ICCC 2017

The IEEE/CIC International Conference on Communication in China(ICCC)has been globally recognized as one of the important annual international conference held by the IEEE Communication Society(Com Soc)and China Institute of Communication(CIC)in China.The sixth IEEE/CIC ICCC 2017 was held in the magnificent city of Qingdao,China,22-24 October,

New Insights into Neoproterozoic–Cretaceous Events in the Mamfe Basin(SW Cameroon,Central Africa):Evidence from Textural Analyses,U-Th Composition,and U-Pb Zircon Geochronology from Granitic Basement

Backscattered electron BSE-CL images,U-Th abundance,and U-Pb ages were obtained for zircons from the Nkogho granitic basement rocks cropping out in the Mamfe Basin(SW Cameroon).These data are used to characterize and classify each zircon,elucidate their geochemical traits.They were also used to formulate a model of their host composition to ascertain the source,and document any preserved postemplacement events.These zircons mainly form long to short prisms that are pyramidal to dipyramidal in shape.They typically exhibit complex oscillatory growth zoning,as well as exhibit sector zoning.These features are mainly compatible with igneous zircons,although a few examples have metamorphic signatures.The U(30 ppm–6380 ppm),Th(4 ppm–1280 ppm),and Pb(12 ppm–648 ppm)contents show core to rim variations with most values fall within the range of crustal granitic zircons.The Th/U ratios(0.08–1.23),with core to rim differences mainly encompass values typical of magmatic zircons with a few values characterizing metamorphic zircons that grew in equilibrium with an anatectic melt.The U-Pb ages(108.4±1.7 to 988.4±19.0 Ma)with some core and rim age differences date Early Neoproterozoic,Cryogenian–Ediacarian,Early Cambrian–Ordovician,Devonian–Carboniferous,and Aptian–Albian events.The arc-like Nkogho I-type granitoid crystallized from granitic magma during Cryogenian to Ediacarian times and was later affected by post-Ediacarian Cambrian to Albian magmatic events.Aptian–Albian ages probably reflect opening of the Mamfe Basin.

Analgesic nanomedicines for the treatment of chronic pain

Chronic pain is a major cause of suffering that often accompanies diseases and therapies,affecting approximately 20%of individuals at some point in their lives.However,current treatment modalities,such as anesthetic and antipyretic analgesics,have limitations in terms of efficacy and side effects.Nanomedical technology offers a promising avenue to overcome these challenges and introduce new therapeutic mechanisms.This article reviews the recent research on nanomedicine analgesics,integrating analyses of neuroplasticity changes in neurons and pathways related to the transition from acute to chronic pain.Furthermore,it explores potential future strategies using nanomaterials,aiming to provide a roadmap for new analgesic development and improved clinical pain management.By leveraging nanotechnology,these approaches hold the potential to revolutionize pain treatment by delivering targeted and effective relief while minimizing side effects.

Impact of climate factors on contact rate of vector-borne diseases： Case study of malaria

Climate change influences more and more of our activities. These changes led to envi- ronmental changes which has in turn affected the spatial and temporal distribution of the incidence of vector-borne diseases. To establish the impact of climate on contact rate of vector-borne diseases, we examine the variation of prevalence of diseases according to season. In this paper, the goal is to establish that the basic reproductive number R0 depends on the duration of transmission period and the date of the first conta- mination case that was declared （to） in the specific ease of malaria. We described the dynamics of transmission of malaria by using non-autonomous differential equations. We analyzed the stability of endemic equilibrium （EE） and disease-free equilibrium （DFE）. We prove that the persistence of disease depends on minimum and maximum values of contact rate of vector-borne diseases.

Perovskite photodetector-based single pixel color camera for artificial vision

Narrowband red,green,blue self-filtering perovskite photodetectors and a broadband white photodetector are incorporated into a single pixel imaging camera to mimic the long-,medium-,and short-wavelength cone cells and rod cells in human visual system,leading to the demonstration of high-resolution color images in diffuse mode.

捻针时真、假穴不同中枢激活效应的脑功能MRI

目的 利用功能磁共振 (fMRI)观察捻针针刺方法对大脑的作用。方法 用盲法随机分别针刺 13例正常人左侧太冲、丘墟和假穴 ,手法采用捻针和不捻针 ,利用 1 5TMR仪行全脑功能成像 ,用SPM99b分析图像。结果 发现只在真穴捻针针刺时有更强的激活效应 ,有显著性意义的Brodmann激活区域为 :针刺太冲穴激活了左右顶叶BA4 0区 ,右额叶BA4 7和 10区 ,右丘脑 ,左小脑 ;针刺丘墟穴激活了左右顶叶BA4 0区 ,右顶叶BA2区 ,左额叶BA9、10、4 4区 ,左岛叶BA13区 ,左颞叶BA2 2区 ,右颞叶BA4 2区 ,右壳核 ,左小脑。两真穴激活部位部分相同 ,部分不同。在假穴捻针对不捻针的研究中 ,未见到有显著性意义的激活区。结论 真穴捻针时可能对皮层神经活动有较特异的作用 ,而假穴未观察到此种现象 ,推测这可能是针刺治疗作用的机制之一。

Cornus mas L.extract as a multifunctional material for manufacturing cosmetic emulsions

Dogwood fruits are a valuable source of active ingredients, such as phenolic compounds, vitamin C, iridoids, flavonoids and anthocyanins. Plant extracts and substances derived from latin Cornus mas L. exhibit not only strong antibacterial but also antioxidant and tonicity properties, effectively preventing the development of inflammation in living organisms. In the present study, we attempted to obtain the innovative, multi-functional plant extract from the fruit of dogwood(Cornus mas L.). During the extraction process a mixture of water, glycerol, and vegetable oil were used as an extractant. The usage of such mixtures of solvents enabled us to extract a variety of active substances, soluble in both water and oils. The obtained extracts were analyzed for their physicochemical and biochemical properties, in order to apply the extract in a body nutrient lotion. The results clearly showed that such extract could be an innovative and multi-functional raw material used in cosmetics industry.

To “tell or not to tell”——Exploring disclosure about medicine use by people living with sleep disorders

Objective: To explore the difference in rates and reasons for disclosure of either conventional or complementary medicine(CM) to healthcare practitioners between people living with sleep disorders(SDs) and those without SDs.Methods: A cross-sectional survey(N = 2019 adults) that measured sociodemographic characteristics,health status, health service utilisation, health literacy and health communication(medicine disclosure)of a representative sample of Australians was conducted. Data from participants reporting an SD(n = 265)were compared to those not reporting an SD to assess measures of health communication and disclosure about medicine use.Results: Overall, rates of medicine disclosure to both conventional and CM practitioners were high, in respondents with(70%) and without an SD(57%). Those reporting an SD had higher expectations of their conventional health practitioner’s knowledge of CM, associated clinical decision-making skills, and approval of CM use, and held a higher degree of concern about drug interactions(P < 0.05). The main reasons cited for disclosing CM use to conventional health practitioners and conventional medicine use to CM practitioners were “I want them to fully understand my health status” and“I was concerned about drug interactions with the CMs used.”Conclusion: The high rate of medicine use disclosure by people with SDs is driven by an intention to inform their healthcare practitioner about their health status and concerns about potential medicine interactions. Therefore, research about the expectations that people with an SD have of their conventional healthcare practitioners’ knowledge of CM and CM-drug interactions requires further examination.Likewise, further examination of CM practitioner’s conventional medicine knowledge is encouraged.

Building a dense surface map incrementally from semi-dense point cloud and RGB images

Building and using maps is a fundamental issue for bionic robots in field applications. A dense surface map, which offers rich visual and geometric information, is an ideal representation of the environment for indoor/outdoor localization, navigation, and recognition tasks of these robots. Since most bionic robots can use only small light-weight laser scanners and cameras to acquire semi-dense point cloud and RGB images, we propose a method to generate a consistent and dense surface map from this kind of semi-dense point cloud and RGB images. The method contains two main steps： （1） generate a dense surface for every single scan of point cloud and its corresponding image（s） and （2） incrementally fuse the dense surface of a new scan into the whole map. In step （1） edge-aware resampling is realized by segmenting the scan of a point cloud in advance and resampling each sub-cloud separately. Noine within the scan is reduced and a dense surface is generated. In step （2） the average surface is estimated probabilistically and the non-coincidence of different scans is eliminated. Experiments demonstrate that our method works well in both indoor and outdoor semi-structured environments where there are regularly shaped objects.

One Chinese political donation does not a scandal make

Let’s be clear.Efforts by any country to subvert Australia should be investigated,monitored and brought to light Yes,let’s ban donations from non-citizens.Let’s go further still-my own suggestion-and ban any donations that might reasonably be suspected as seeking to influence Australian foreign policy.However,almost a week after ABC’s Four Corners screened its episode Power and Influence: