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Rolling bearing performance often degrades due to extra wear introduced by sliding-rolling contacts. Thus, it is vital to monitor the evolution of such wear process through investigating the worn surface. Compared with traditional two-dimensional (2-D) methods, three-dimensional (3-D) measurements of worn surfaces can provide more information. Due to the lack of in-situ 3-D measurement techniques and the scale-dependency of characterization parameters, it remains a challenge to examine the wear evolution of sliding-rolling contact using 3-D surface topography features. A characterization framework is here developed for inspecting worn surface topography variations under sliding-rolling contact, by combing 3-D surface reconstruction and computed fractal dimension. The worn surface is firstly imaged by an in-situ microscope. Next, a virtual 3-D surface is obtained from 2-D images via topography reconstruction. Then, the fractal dimension of worn surfaces is calculated to characterize the wear state with 3-D root-mean-square. A wear test is carried out on a roller-ring test rig to verify the proposed method. Results indicate that the proposed 3-D characterization performance is comparable to laser scanning confocal microscopy (LSCM) and allows rapid description of the wear process.

The purpose of our study was to review and evaluate the efficacy and safety of nerve combing without neurovascular decompression for trigeminal neuralgia. A retrospective review of 298 patients with trigeminal neuralgia between August 2007 and August 2016 was conducted. The patients were divided into two groups: the A group was treated by nerve combing (34 patients) and the B group received microvascular decompression (264 patients). Surgical outcomes and postoperative complications were compared between the two groups. Pain was completely relieved in 88.2% of group A patients and 92.8% of group B after surgery. The median duration of follow-up was 60 months (range 10–115 months) in group A and 62 months (range 12–118 months) in group B. 72.7% and 86.4% of cases were completely relieved in groups A and B, respectively. There were no statistically significant differences in the surgical outcomes between the two groups. Almost all patients experienced some degree of numbness or hypesthesia (76.5%). The rate of facial numbness in group A was significantly higher than that in group B. This study demonstrated that nerve combing without neurovascular decompression is a safe and effective treatment for trigeminal neuralgia. However, a majority of patients treated with nerve combing experienced some degree of facial numbness.

The party building work of colleges and universities occupies a key position in all the work of colleges and universities. It is an important guarantee for promoting colleges and universities to fulfill the mission of cultivating people and achieve long-term and steady development. Entering the new era, under the new environment and situation, the party building work in colleges and universities is facing a series of opportunities and challenges. The current international political situation is becoming more and more severe. The domestic comprehensive and strict governance of the party continues to advance, and improving the quality of party building is an inevitable requirement of the new era and an important task of the new era. The work of party building in colleges and universities, like other grassroots party organizations, must have a scientific and reasonable quantitative evaluation system, otherwise its quality and level cannot be judged objectively. Based on the background and significance of the research on the quality evaluation system of party building work in universities, this article combs the research results of domestic scholars on the system, hoping to provide some reference for perfecting the system, improving the quality of party building work in universities and realizing the path and method of the overall development of universities.

Plant segmentation is an important application of computer vision processing technology in agriculture. Relying on plant segmentation technology, many crop problems can be significantly discovered and prevented. At the same time, plant conditions can be quickly and accurately understood, thereby increasing yield. This paper proposes a plant segmentation method based on the combination of color index and region growing. Threshold on the color index image produces object mask and background mask. The rest of pixels are segmented by region growing with the mask as seed points. The region growing is implemented with a simple non-iterative clustering method. The experimental results on four sets of data sets show that the accuracy has been improved with our method compared to index-based method.

Combing geochemical and seismological results constrains the composition of the middle and lower continental crust better than either field can achieve alone. The inaccessible nature of the deep cr...

B-cell epitopes (BCEs) are a set of specific sites on the surface of an antigen that binds to an antibody produced by B-cell. The recognition of BCEs is a major challenge for drug design and vaccines development. Compared with experimental methods, computational approaches have strong potential for BCEs prediction at much lower cost. Moreover, most of the currently methods focus on using local information around target residue without taking the global information of the whole antigen sequence into consideration. We propose a novel deep leaning method through combing local features and global features for BCEs prediction. In our model, two parallel modules are built to extract local and global features from the antigen separately. For local features, we use Graph Convolutional Networks(GCNs) to capture information of spatial neighbors of a target residue. For global features, Attention-Based Bidirectional Long Short-Term Memory(Att-BLSTM) networks are applied to extract information from the whole antigen sequence. Then the local and global features are combined to predict BCEs. The experiments show that the proposed method achieves superior performance over the state-of-the-art BCEs prediction methods on benchmark datasets. Also, we compare the performance differences between data with or without global features. The experimental results show that global features play an important role in BCEs prediction. Our detailed case study on the BCEs prediction for SARS-Cov-2 receptor binding domain confirms that our method is effective for predicting and clustering true BCEs.

The identification of distributed dynamic loads is an important but challenging task because a distributed dynamic load is composed of both time and space functions. This paper proposes a n...

&nbsp, This research studied the influence of three types of open (short-straight, long-straight, semicircular) and three different shapes of closed steel fibers (triangular, rectangular, circular) with different fiber contents by volume (0, 0.5%, 1%, 1.5%, and 2%) on the working and mechanical performance of reactive powder concrete (RPC). The results indicated that (1) the number of steel fibers and the enclosed area formed by closed steel fibers would remarkably impact the performance of RPC, (2) the semicircular fiber improves RPC’s strength the most among the three open shapes, (3) the short-straight fiber works more effectively than the closed steel fibers, (4) the circular fiber works the most efficiently in improving RPC’s mechanical performance while the triangular ones have the least effect among the three closed steel fibers, (5) both the closed and open steel fibers improve their compressive strength more than their flexural strength, (6) the closed steel fiber works more efficiently in improving the flexural strength but less efficiently in improving the compressive strength, (7) the open steel fibers enhance the mechanical performance of RPC via their anchoring performance while the closed steel fibers work by confining the concrete, (8) the hybrid utilization of steel fibers improves RPC’s mechanical performance to a higher level via combing the advantages of open and closed steel fibers.

Tied links in $S^3$ were introduced by Aicardi and Juyumaya as standard links in $S^3$ equipped with some non-embedded arcs, called {\it ties}, joining some components of the link. Tied links in the Solid Torus were then naturally generalized by Flores. In this paper we study this new class of links in other topological settings. More precisely, we study tied links in the lens spaces $L(p,1)$, in handlebodies of genus $g$, and in the complement of the $g$-component unlink. We introduce the tied braid groups $TB_{g, n}$ by combining the algebraic mixed braid groups defined by Lambropoulou and the tied braid monoid, and we state and prove Alexander's and Markov's theorems for tied links in the 3-manifolds mentioned above. Finally, we emphasize on further steps needed in order to study tied links in knot complements and c.c.o. 3-manifolds, which is the subject of a sequel paper., Comment: 20 pages, 25 figures

Detection distance is a critical specification in automotive driving. The output power of a power amplifier is the bottleneck for the detection range. In this work, a design of 77 GHz power amplifier is presented in a 40 nm CMOS technology with a four-way parallel-series power combing technique for achieving a 20 dBm output power (Psat), which meets a 186-meter detection range in the conditional of 30 mm/h rainfall capacity. In this parallel-series power combing technique, distributed active transformers perform load-pull matching and in-phase power combining. It achieves a compact solution for future on-chip antenna integration. This PA is optimized for maximal power-added efficiency of 21.35% with 20 dBm saturated output power at 77 GHz.

FastText is a text classification model by Facebook. As the model is simple in structure, it has the advantage of fast and efficient. However, when the model is used in Chinese text classification, the accurate rate will decrease. To this end, a Chinese FastText text classification method combing Term Frequency-Relevance Frequency (TF-RF) and improved random walk model is suggested in the paper. The method makes TF-R weight choice to N-gram processed dictionaries during the input stage of the FastText model, making semantic analysis by using Probabilistic Latent Semantic Analysis (PLSA), and supplements to feature words; then utilizes the improved random walk model to improve the accuracy, and the improved model is more suitable for Chinese text classification. The experiment result shows that improved model in the paper has a better effect to Chinese text classification.

A compact, double sided cooled, 6-in-1 IGBT module has been designed with an innovative packaging structure combing the different advanced packaging technologies. This paper reports the packaging technologies used to assemble the module, the improved thermal and electrical performance of the assembled module in comparison with a commercially available high performance IGBT module, and the proven power cycling reliability of the present module assembled using the optimized structure, material and processing factors. The present IGBT module can hence provide more efficient solutions for applications in EV /HEV motor controls.

We combine the empirical matched field (EMF) method and machine learning using Convolutional Neural Networks (CNNs) for calving event detection at the IMS station SPITS and GSN station KBS on the Arctic Archipelago of Svalbard. EMF detection with seismic arrays seeks to identify all signals similar to a single template generated by seismic events in a confined target region. In contrast to master event cross-correlation detectors, the detection statistic is not the waveform similarity, but the array beam power obtained using empirical phase delays (steering parameters) between the array stations. Unlike common delay-and-sum beamforming, the steering parameters do not need to represent a plane wave and are directly computed from the template signal without assuming a particular apparent velocity and back-azimuth. As for all detectors, the false alarms rate depends strongly on the beam power threshold setting and therefore needs appropriate tuning or alternatively post-processing. Here, we combine the EMF detector using a low detection threshold with a post-detection classification step. The classifier uses spectrograms of single-station three-component records and state-of-the-art CNNs pre-trained for image recognition. Spectrograms of three-component seismic data are hereby combined as RGB images. We apply the methodology to detect calving events at tidewater glaciers in the Kongsfjord region in Northwestern Svalbard. The EMF detector uses data of the SPITS array, at about 100 km distance to the glaciers, while the CNN classifier processes data from the single three-component station KBS at 15 km distance using time windows where the event is expected according to the EMF detection. The EMF detector combines templates for the P and for the S wave onsets of a confirmed, large calving event. The CNN spectrogram classifier is trained using classes of confirmed calving signals from four different glaciers in the Kongsfjord region, seismic noise examples, and regional tectonic seismic events. By splitting the data into training and test data set, the CNN classifier yields a recognition rate of 89% on average. This is encouragingly high given the complex nature of calving signals and their visually similar waveforms. Subsequently, we process continuous data of 6 months in 2016 using the EMF-CNN method to produce a time series of glacier calving. About 90% of the confirmed calving signals used for the CNN training are detected by EMF processing, and around 80% are assigned to the correct glacier after CNN classification. Such calving time series allow us to estimate and monitor ice loss at tidewater glaciers which in turn can help to better understand the impact of climate change in Polar regions. Combining the superior detection capability of (less common) seismic arrays at a larger source distance with a powerful machine learning classifier at single three-component stations closer to the source, is a promising approach not only for environmental monitoring, but also for event detection and classification in a CTBTO verification context.

It is possible to achieve mass production by multiple patterning technology combing with 193 immersion scanners at 7nm technology node. The application of freeform illumination source shapes is a key enabler for continued shrink using 193 nm immersion lithography with 1.35 NA. Source and mask optimization (SMO) is the important resolution enhancement technique (RET) to optimize a satisfied freeform source. Design pattern library can be used to cognize, manage and compare all the continuous changing and iterative physical designs. Our proposed methodology can improve SMO performance by taking advantages of post-color design pattern library and pattern selection method. And process window limiters are the important guidance to optimize parameters of SMO.

In this paper, we investigate the existence, multiplicity and asymptotic property of positive solutions for a Kirchhoff type problem with indefinite conditions. The existence, multiplicity of positive solutions are obtained by using variational method and the critical point theory, and then combing with some analytical techniques, we have the asymptotic property of positive solutions when $$\lambda$$ approach 0.

Afro hair breakage is most commonly attributed to grooming practices such as braiding, hair extensions and weaves, both for chemically treated hair and natural Afro hair. These grooming practices are also frequently associated with traction alopecia in clinical studies. However, there is little to no quantitative scientific data on the surface and internal hair fibre damage caused by grooming, including combing, on Afro hair.Qualitative and quantitative techniques such as scanning electron microscopy, cuticle cohesion and tensile testing were used to determine the effects of frequent braiding on the integrity of female Afro hair in 15 frequent braiders and 15 occasional braiders (control group) in Johannesburg, South Africa. Frequent braiders were women who braided more than 8 times per year, while occasional braiders typically limit braiding to only twice 2 per year. The severity of traction alopecia was quantified in both groups using the standard Marginal Traction Alopecia Scoring system. Surface damage on naturally curly Afro hair, that was combed but not braided, was assessed as another hairstyle option.All measurements showed a relationship between surface and internal hair fibre damage and braiding frequency. Frequent braiders had thinner hair, with more cuticle damage as shown by SEM and cuticle cohesion assessments. Their hair fibres were also significantly weaker (p 0.05), as shown by the tensile testing. In addition, they also had higher traction alopecia severity scores. In the combing impact assessment, a linear trend was observed between surface hair fibre damage and the number of combing strokes. Cuticle damage from 480 combing strokes was more severe than that from frequent braiding.Frequent braiding and combing damage natural Afro hair. Quantification of damage caused by different grooming practices identifies a need to develop products that could help mitigate specific hair damage associated with grooming practices. The degree of damage and subsequent hair loss could also be minimized by education on best braiding practices to protect the hair fibre and avoid hair follicle miniaturization caused by high traction hairstyles.La casse des cheveux d’origine Africaine est le plus souvent associées à des pratiques cosmétiques telles que le tressage et les extensions de cheveux, à la fois pour les cheveux traités chimiquement et les cheveux naturels. Ces pratiques cosmétiques sont également fréquemment associées à une alopécie de traction, comme le relatent les études cliniques. Cependant, il existe peu ou pas de données scientifiques quantitatives sur l’impact de ce type de pratiques, y compris le peignage, sur les dommages internes et de surface des cheveux d’origine africaine. MÉTHODES: Des techniques qualitatives et quantitatives, comme la microscopie électronique à balayage (MEB), la cohésion cuticulaire et des tests de traction, ont été utilisés pour déterminer les effets du tressage sur l'intégrité des cheveux de deux groupes de 15 femmes Africaines (à Johannesburg, Afrique du Sud) : un premier groupe de femmes pratiquant un tressage fréquent et un autre groupe un tressage occasionnel. Le groupe des tresseurs fréquents correspond à des femmes qui pratiquent le tressage plus de 8 fois par an, tandis que les tresseurs occasionnels limitent généralement le tressage à seulement deux fois par an. La gravité de l'alopécie de traction a été également quantifiée dans les deux groupes à l'aide du système standard de notation de l'alopécie tractionnelle. Parallèlement, à titre de comparaison, les dommages de surface ont été également évalués sur des cheveux d’origine Africaine naturellement bouclés, non tressés, mais qui ont subi un peignage répété. RÉSULTATS: Toutes les mesures ont montré une relation entre les dommages de surface et internes de la fibre et la fréquence de tressage. Les tresseurs fréquents ont des cheveux plus fins, avec un endommagement plus important de la cuticule, comme le montrent les évaluations MEB et la cohésion cuticulaire. Les cheveux sont également significativement plus fragiles (p0,05), comme le montrent les tests de traction. De plus, ces femmes ont également des scores d'alopécie de traction plus élevés. Dans le cas spécifique du peignage répété, une tendance linéaire a été observée entre les dommages en surface de la fibre capillaire et le nombre de coups de peigne. On peut également noter que l’endommagement de la cuticule causé par 480 coups de peigne est plus important que celui causé par des tressages fréquents.Les tressages et peignages fréquents endommagent les cheveux naturels d’origine Africaine. La quantification des dommages causés par différentes pratiques cosmétiques met en évidence le besoin de développer des produits qui pourraient aider à atténuer les dommages liés à des pratiques spécifiques. Le niveau de dommage et la perte de cheveux pourraient également être minimisés par un apprentissage de meilleures pratiques de tressage pour protéger la fibre et éviter la diminution des follicules pileux causée par des coiffures qui entrainent un forte traction sur la fibre.

It is statistically proved that in production of grain crops, harvesting is the most labor-and resource-intensive. A comparative technical and economic assessment of technologies for harvesting winter wheat by direct harvesting and combine harvesting was carried out. The calculations performed under the conditions of the model economy of the region proved the economic feasibility of updating the fleet of grain harvesting equipment with machines equipped with combing adapters for harvesting grain crops.

At present, when cultivating various agricultural crops, there is an increased load of machine-tractor units on the soil horizon, due to the use of multi-operational tillage technology. The family of universal high-speed cultivators UKS of 10-, 12- and 14-meters working width simultaneously performs the following technological operations: loosening without turning the layer with cutting and combing out weeds, as well as compacting and mulching the soil surface. UKS cultivators include the following structural elements: a frame with a hitch, a hydraulic system, a disc bar, a frame consisting of the middle and side sections and wings on the transverse bars of which there are five rows of duckfoot paws, support-running wheels, and a scraper frame with seals. In the course of field research of the developed universal high-speed cultivators, it was established that their quality indicators correspond to the agrotechnical requirements: the deviation of the processing depth from the average does not exceed 1.5 cm; the presence of ridges on the surface of the field less than 3 cm high; the number of fractions less than 25 mm in size (crumbling) was more than 80%; crop and plant residues remained on the surface of the field by at least 80%.

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The combination model is a widely used method way in machine learning to design the more sophisticated and well-performed model, which can be applied for the field of the recommendation system and so on. This paper is aims to explore the prediction model The normal prediction models have to deal with neither dense numerical features or sparse categorical features. Decision tree is a popular way to deal with dense data, doing both regression and classification. It has various famous expanding algorithms, such as GBDT, XGBoost, and so on, which is designed by different ways of combing the basic decision tree. GBDT and XGBoost are both good at Large-scale machine learning and perform well with dense numerical features. As for sparse categorical features. FM is no doubt the best basic algorithm designed for it. By combing FM with other models, Wide&Deep and DeepFM are better for the recommended system because they perform well and can deal with high-order feature intersection. Furthermore, we can not only just add models together, Deep&Cross and DeepGBM are examples which use NN (natural network) to approximate other models, combing the different parts to an integration. And NN can not only substitute the model is approximated, but also is suited for the online training. This paper is aims to explore the development of the prediction models and the future trend for its improvement.

Shared travel plays a more and more active role in the emergence of urban traffic, but there is no systematic and perfect combing and analysis on the study of bike-sharing without piles, especially on its operation and management mode. This paper will conduct a comprehensive data analysis on the research of bike-sharing without piles from the individual micro level and the enterprise government level, and explore the research focus and possible subject areas of future research.

Coal macrolithotypes control the reservoir heterogeneity, which plays a significant role in the exploration and development of coalbed methane. Traditional methods for coal macrolithotype evaluation often rely on core observation, but these techniques are non-economical and insufficient. The geophysical logging data are easily available for coalbed methane exploration, thus, it is necessary to find a relationship between core observation results and wireline logging data, and then to provide a new method to quantify coal macrolithotypes of a whole coal seam. In this study, we propose a L-Index model by combing the multiple geophysical logging data with principal component analysis, and we use the L-Index model to quantitatively evaluate the vertical and regional distributions of the macrolithotypes of No. 3 coal seam in Zhengzhuang field, southern Qinshui basin. Moreover, we also proposed a S-Index model to quantitatively evaluate the general brightness of a whole coal seam: the increase of the S-Index from 1 to 3.7, indicates decreasing brightness, i.e., from bright coal to dull coal. Finally, we discussed the relationship between S-Index and the hydro-fracturing effect. It was found that the coal seam with low S-Index values can easily form long extending fractures during hydraulic fracturing. Therefore, the lower S-Index values indicate much more favorable gas production potential in the Zhengzhuang field. This study provides a new methodology to evaluate coal macrolithotypes by using geophysical logging data.

Analyses of the DNA fibers have become a central technique to investigate the phenomena causing genomic instability in the field of cytogenomics. Molecular combing has achieved a high value in replication analyses and genome integrity with greater resolution and robustness. In the replication assay, cells are pulsed with two different thymidine analogs. While for the Genome Morse Code (GMC), specific probes are designed to build a unique pattern of color for the characterization of specific genome sequences. DNA molecules are combed at a specific parameter (2 kb per micrometer) on specific chemical-treated coverslips. Thus, DNA single molecules are parallel aligned with a constant stretching factor to each other. Molecular combing has strong value and potentiality for investigations regarding the replication stress response: such as monitoring changes in the kinetics of replication forks and origins. Alternatively, the GMC analyses bring to the identification and quantification of genomic rearrangements and genetic modifications.

The paper analyzes the most common types of weeds in the Volgograd region. The main physiological and physical-mechanical features of weeds are described. The authors identified the most harmful weeds and features of their growth. The results of studying the technological process of removing weeds together with the root system with the simultaneous high-quality loosening of the soil are presented. The technological process of operation of an auto-driven sectional working body is described. The paper describes the movement trajectory of the knives of front and rear rotors during the operation of the unit. The hole dimensions were determined when cultivating the soil with a knife of the front rotor of an auto-driven working body. The dependence of the gear ratio between the front and rear rotors, the long root extracted to the field surface, and the speed of the unit were established. As a result of experimental studies, it was found that the optimal gear ratio between the rotors of the self-driving tillage unit should be in the range from 3.5 to 3.8, while the forward speed of the unit is 2.5–3.5 m/s. These technological parameters are the fundamental factors in creating a complex technological process of combing out weeds from the soil in place of the root and laying them on the surface.

First, this chapter will try to define the concept of rural–urban relations. Then, the method of theoretical research will be determined. Finally, on the basis of combing the research literature on rural–urban relations systematically, the author evaluates the existing research results comprehensively and summarizes the main line through the theoretical evolution.

The natural fibre reinforced composites have the advantage of being light weight, renewable, cheap and eco–friendly when compared to the synthetic fibres. So, there is a need to investigate potentiality of natural fibre which can be used in highly demanding situations. An attempt has been made in the present work to explore the possible uses of variety of cultivated and wild grown fibres in nature that aids in the development of new composites for load carrying structures. The present research work has been carried out to make use of okra /sisal natural fibres. The aim of this paper is to describe the experimental development and characterization of new set of hybrid natural fibre composites which is made by reinforcing okra /sisal fibres with polyester resin in matrix by using hand layup method. The natural fibres were extracted by retting and combing process manually. The hybrid composites were prepared using okra/sisal fibres of 30/70, 50/50, 70/30 fibre weight ratios, when subjected to varying weights of fibres (0. 4, 0. 8, 1. 2, 1. 6, 2) grams. The tensileand impact properties were carried out using hybrid composite specimens.

In this paper we compute the Kauffman bracket skein module of the complement of $(2, 2p+1)$-torus knots, $KBSM(T_{(2, 2p+1)}^c)$, via braids. We start by considering geometric mixed braids in $S^3$, the closure of which are mixed links in $S^3$ that represent links in the complement of $(2, 2p+1)$-torus knots, $T_{(2, 2p+1)}^c$. Using the technique of parting and combing, we obtain algebraic mixed braids, that is, mixed braids that belong to the mixed braid group $B_{2, n}$ and that are followed by their ``coset'' part, that represents $T_{(2, 2p+1)}^c$. In that way we show that links in $T_{(2, 2p+1)}^c$ may be pushed to the genus 2 handlebody, $H_2$, and we establish a relation between $KBSM(T_{(2, 2p+1)}^c)$ and $KBSM(H_2)$. In particular, we show that in order to compute $KBSM(T_{(2, 2p+1)}^c)$ it suffices to consider a basis of $KBSM(H_2)$ and study the effect of combing on elements in this basis. We consider the standard basis of $KBSM(H_2)$ and we show how to treat its elements in $KBSM(T_{(2, 2p+1)}^c)$, passing through many different spanning sets for $KBSM(T_{(2, 2p+1)}^c)$. These spanning sets form the intermediate steps in order to reach at the set $\mathcal{B}_{T_{(2, 2p+1)}^c}$, which, using an ordering relation and the notion of total winding, we prove that it forms a basis for $KBSM(T_{(2, 2p+1)}^c)$. We finally consider c.c.o. 3-manifolds $M$ obtained from $S^3$ by surgery along the trefoil knot and we discuss steps needed in order to compute the Kauffman bracket skein module of $M$. We first demonstrate the process described before for computing the Kauffman bracket skein module of the complement of the trefoil, $KBSM(Tr^c)$, and we study the effect of braid band moves on elements in the basis of $KBSM(Tr^c)$. These moves reflect isotopy in $M$ and are similar to the second Kirby moves., Comment: 27 pages, 18 figures

At present, building information modeling is widely used in many stages of project life cycle. On the basis of combing the practical teaching of engineering management specialty, this paper analyzes the practice teaching conditions based on BIM Technology in application-oriented universities, and puts forward the construction measures of teaching system of BIM Technology in engineering management practice teaching.

Combing the advantages of film cooling, impingement cooling, and enhanced cooling by pin fins, laminated cooling is attracting more and more attention. This study investigates the effects of geometric and thermodynamic parameters on overall cooling effectiveness of laminated configuration, and model experiments were carried out to validate the numerical results. It is found that the increases in film cooling hole diameter and pin fin diameter both result in the increase in cooling effectiveness, but the increases in impingement hole diameter, impingement height, and spanwise hole pitch degrade the cooling performance. The increase of the coolant flow rate causes the increase in cooling efficiency, but this effect becomes weaker at a high coolant flow rate. The coolant-to-mainstream density ratio has no obvious effect on cooling effectiveness but affects wall temperature obviously. Moreover, based on the numerical results, an empirical correlation is developed to predict the overall cooling efficiency in a specific range, and a genetic algorithm is applied to determine the empirical parameters. Compared with the numerical results, the mean prediction error (relative value) of the correlation can reach 8.3%.

Background The preoperative prediction of the recurrence of chronic rhinosinusitis with nasal polyps (CRSwNP) remains difficult in clinical practice. Objective We aimed to develop a nomogram that combined peripheral risk factors to clinically predict the recurrence of CRSwNP. Methods Data from 158 CRSwNP patients who underwent endoscopic sinus surgery (ESS) from January 2012 to December 2016 were collected, and the patients were followed up for 3 years. Of these, 96 patients who underwent ESS in an earlier period formed the training cohort for nomogram development, and 62 patients who underwent ESS thereafter formed the validation cohort to confirm the model’s performance. Risk factors for recurrence identified by univariate and multivariate logistic regression were used to create a nomogram. Results The recurrence rate was 29.2% (28/96) for the training cohort and 35.5% (22/62) for the validation cohort. Univariate analysis identified blood eosinophils (Eos), serum IgE level, asthma comorbidity, and the number of previous ESSs as risk factors for recurrence. Among those four parameters, serum IgE level and a previous ESS surgery were identified as two independent risk factors. A nomogram consisting of blood Eos, total serum IgE level, asthma comorbidity, and the number of previous ESSs was constructed, demonstrating a C index of 0.81 (95% CI, 0.79-0.83) and 0.80 (95% CI, 0.77-0.83) for predicting recurrence in the training and validation cohorts, respectively. The nomogram had well-fitted calibration curves. Conclusion The nomogram might be able to preoperatively predict the recurrence of CRSwNP by using currently available and objective parameters. Further studies are required to validate its reliability and effectiveness.

To widen bridges, a usual method is to cast joint connections between new and old bridge decks without traffic interruption. The traffic vibrations have negative influence on the quality of joint connections. Shortening the construction time can alleviate the impact on the traffics, a fast-hardening retarding high-early-strength concrete (FRHC) for the connections is in need. In this study, low-alkalinity sulphoaluminate cement (LASC) concrete was modified to gain these characteristics. Based on FRHC concrete, four slab specimens including a monolithic concrete slab and three joint FRHC slabs were cast to investigate their flexural behaviors. With proper splicing details in joint connections, the joint FRHC specimens behaved approximately similar to the monolithic specimen. Combing the laboratory tests and engineering practice, the newly developed FRHC mixture succeeded in fast-hardening, retarding and high-early strength and the joint connections filled with FRHC have a good flexural performance.

To solve the problem of predicting daily arrival number of people belonging to a specific group, this paper proposes a hybrid model which integrates linear component (from ARIMA model) with non-linear component (from BP neural network). The experimental results indicate that, hybrid methodology that has both linear and nonlinear modeling capabilities is a good strategy for practical use.

The international passenger points layout problem of a large aviation hub is analyzed by introducing potential points and contribution. Focusing on the collection of potential international points, and the layout principle combing balanced development and contribution priority, a “three-step” international passenger points layout method based on the idea of stabilizing the stock and optimizing the increment is constructed aiming to better support the unique strategic function positioning and aviation market of a large aviation hub. The empirical analysis shows that the international passenger points layout scheme of a large aviation hub in China is made combing existing 35 points with 60 new points to form a “Belt and Road” countries as the focus, smooth access to Asia and Europe, and then to five continents; and the international passenger points layout method of some large aviation hub constructed in this paper is feasible and effective.

In most cities, the monitoring stations are sparse, and air pollution is affected by various internal and external factors. To promote the performance of regional pollution prediction, a deep spatio-temporal dense network model is proposed in this paper. First, the inverse distance weighted (IDW) space interpolation algorithm is used to construct historical emission data with insufficient station records. Based on the properties of spatial-temporal data, a deep spatial-temporal dense network model is designed to predict air pollution in each region. Finally, several experiments are conducted on the real dataset of Hangzhou. The results show that combing IDW spatial interpolation and deep spatial-temporal dense network model can effectively predict the regional air pollution and achieve superior performance compared with ARIMA, CNN, ST-ResNet, CNN-LSTM.

Cosmetic and dermatological products, mainly the hair treatments, are projected to have remarkable growing in coming years. Nanotechnology, specifically nanoemulsions, has potential to be used in several hair products, owing to their beneficial properties. Concurrently, plant-derived cosmetics have become more popular over the years to consumers who prefer a safer, natural and sustainable approach. There is a lack of studies combining plant oils and nanotechnology for haircare formulations. In this work, different plant oil-loaded nanoemulsions were prepared to investigate the influence of their particle size, zeta potential and composition on hair treatment efficacy.Coconut, olive and Abyssinian oils, alone or in combination, were loaded into nanoemulsions by high-pressure homogenization method (HPH). The mean particle size, polydispersity index and zeta potential were measured by the dynamic light scattering (DLS) method, and a stability test was performed for five months. A sensorial screening evaluation performed by the analyst and the combing test using Dia-StronThe use of different plant oils for nanoemulsion resulted in distinct final particle sizes and zeta potential. However, results suggested no significant difference between them in hair tresses combing efficacy compared by Dia-StronThe composition of plant oils, particle size or zeta potential of the prepared nanoemulsions does not seem to significantly influence hair performance. Thus, we suggest that finding the right balance between cationic surfactant and plant oils may be the most appropriate path to develop effective nanoemulsions in hair treatment.Les produits cosmétiques et dermatologiques, principalement les traitements capillaires, devraient connaître une croissance remarquable dans les années à venir. La nanotechnologie, en particulier les nanoémulsions, a le potentiel d'être utilisée dans plusieurs produits capillaires, en raison de leurs propriétés bénéfiques. Parallèlement, les cosmétiques d'origine végétale sont devenus plus populaires au fil des ans auprès des consommateurs qui préfèrent une approche plus sûre, naturelle et durable. Il existe un manque d'études combinant les huiles végétales et la nanotechnologie pour les formulations de traitement capillaire. Dans ce travail, différentes nanoémulsions contenant de l'huile végétale ont été préparées pour étudier l'influence de leur taille de particule, de leur potentiel zêta et de leur composition sur l'efficacité du traitement capillaire. MÉTHODES: Les huiles de noix de coco, d'olive et d'Abyssinie, seules ou en combinaison, ont été chargées dans des nanoémulsions par méthode d'homogénéisation à haute pression (HPH). La taille moyenne des particules, l'indice de polydispersité et le potentiel zêta ont été mesurés par la méthode de diffusion dynamique de la lumière (DLS), et un test de stabilité a été effectué pendant cinq mois. Une évaluation sensoriel réalisée par l'analyste et le test de peignage à l'aide de l'instrumentation Dia - Stron® ont été appliqués sur les cheveux traités par ces nanoémulsions. RÉSULTATS: L'utilisation de différentes huiles végétales pour la nanoémulsion a donné des tailles de particules finales et un potentiel zêta distinct. Cependant, les résultats n'ont suggéré aucune différence significative entre eux dans l'efficacité du peignage des cheveux par rapport aux tests d'instruments Dia-Stron®. De plus, la nanoémulsion chargée avec une concentration plus élevée de tensioactif cationique a indiqué une réduction de 50% de la force de peignage en utilisant ce dispositif par rapport au contrôle, et, le screening a montré de meilleurs résultats sensoriels par rapport aux autres nanoémulsions et contrôle.La composition des huiles végétales, la taille des particules ou le potentiel zêta des nanoémulsions préparées ne semblent pas influencer significativement les performances capillaires. Ainsi, nous suggérons que trouver le bon équilibre entre un tensioactif cationique et des huiles végétales peut être la voie la plus appropriée pour développer des nanoémulsions efficaces dans le traitement des cheveux.

With the increase of signal rate, differential interconnection becomes more and more widely used. However, when the differential pair is asymmetric in layout, e.g., bending lines, common mode noise will be produced in the circuit, which may further cause EMI problems. In this paper, an efficient method, i.e., combing a U-shaped complementary open loop defective ground structure (DGS) with adding slow wave structure at the inner bending line, is proposed to suppress the differential-to-common mode conversion and common-mode noise of right angle bend discontinuity for differential signaling. The simulation results show that the mode conversion can be reduced to less than - 50dB in the bandwidth from DC to 16GHz. Moreover, the common mode noise is also significantly suppressed.

In this paper, kinematic modeling and analysis of a planar flexible parallel robot with large-deformation links are presented via the Beam Constraint Model (BCM). The planar parallel robot uses flexible panels to form the closed-loop branch chains and its moving platform is actuated by the bending deflection of the panels. For kinematic analysis, first the geometric constraints and load equilibrium equations of the moving platform are formulated. Then, the flexible panels with large deformation are modeled as Euler-Bernoulli beams, and the relationship between the force/moment and the deflection of flexible panels is established via BCM. By combing the load equilibrium equations, the analytic formulation of kinematics can be derived. Numerical simulation and the comparison with the finite element analysis (FEA) have been presented to demonstrate the effectiveness of the proposed method.

A compact circular-polarization discriminator is presented in this paper. The proposed structure is composed of three simple layers, which are connected by air spacers. The first and third layers act as circular polarisers (CPs), and the second one is a linear polarizer (LP). By combing the three layers together, the right-handed circularly-polarized wave (RHCPW) can be reflected, while the left-handed circularly-polarized wave (LHCPW) can be transmitted through the proposed structure. Within the operating band, the insertion loss is lower than 2.5 dB. Finally, the proposed design is validated by both simulated and measured results.

The standard IEC 62751 proposed a valve power loss evaluation method combing analytical formulae and numerical simulation for modular multilevel converter (MMC). However, the illustration of building a MMC model and processing simulation results have not been addressed. And also, obtaining solutions from a diodes and IGBTs based simulation model can cost excessively long time. A fast power loss evaluation method is proposed in this paper by linking the PSCAD/EMTDC and Matlab files. Detailed valve power loss analysis of a 201-level 500MW MMC operating at 50Hz$\sim$1000Hz is then presented. Relationship between the valve power loss, power transfer level and operating frequencies are presented and fitted. Research results of this paper can be used as guidance for the application of medium and high frequency MMC.

Graphs and graph-processing have become increasingly important. This has led to an explosion in the development of graph-processing systems, each of which is evaluated relative to its predecessors. In the absence of a large corpus of real-world graphs, synthetic generators provide an easy way to construct graphs of varying sizes. The most widely used generator is the Kronecker generator. Unfortunately, the Kronecker generator was not designed to produce graphs for benchmarking and when used in this fashion, it is problematic in two ways. First, the fraction of zero-degree vertices scales with the graph size, dramatically reducing the effective size of the connected graph. Second, the generator produces a vertex degree distribution not found in real world settings. We demonstrate these phenomena and present the Smooth Kronecker Generator, which remedies the vertex degree distribution problem without changing the statistical properties of the graph.

Single-walled carbon nanotube (SWCNT)/Bi2Te3 composite powders were fabricated via a one-step in situ reductive method, and their corresponding bulk composites were prepared by a cold-pressing combing pressureless sintering process or a hot-pressing process. The influences of the preparation methods on the thermoelectric properties of the SWCNT/Bi2Te3 bulk composites were investigated. All the bulk composites showed negative Seebeck coefficients, indicating n-type conduction. A maximum power factor of 891.6 &mu, Wm&minus, 1K&minus, 2 at 340 K was achieved for the SWCNT/Bi2Te3 bulk composites with 0.5 wt % SWCNTs prepared by a hot-pressing process, which was ~5 times higher than that of the bulk composites (167.7 &mu, 2 at 300 K) prepared by a cold-pressing combing pressureless sintering process, and ~23 times higher than that of the bulk composites (38.6 &mu, 2 at 300 K) prepared by a cold-pressing process, mainly due to the enhanced density of the hot-pressed bulk composites.

It is reasonable to consider combing IRE and RFA. Thus the changes of liver properties after electoporation were studied. The electrical and thermal conductivity of rabbit livers treated by electric shocks with different conditions were measured in vivo through the four-electrode method and the thermistor method respectively. Frequency and electric field were considered, as two main factors of IRE. Experiments then showed that changes occurred in both electrical and thermal conductivity after electoporation treatment. Electric field strength contributed more on electrical conductivity than frequency did. Besides, electrical conductivity significantly increased in all protocols, while thermal conductivity didn't perform so until electric field strength was more than 500V/cm. The related formulas were also given after curve fitting.

In this study, we introduce a data stream method for dynamic runoff simulation, which allows capturing the evolving relationship between runoff and its impact factors (e.g., temperature, rainfall). The basic idea is to view continuously arriving data of runoff and its impact factors as a data stream, and dynamically learn its relationship. To validate the effectiveness of the proposed method, we compare its performance with that of three data driven models (ANN, SVR, Random Forest) and six representative hydrological models (SWAT, AWBM, SimHyd, SMAR, Sacramento, and Tank) in simulating monthly runoff. The proposed method performs well with the best NSE of 0.88, being superior to comparable models. Furthermore, the data stream model also shows its advantage in the flexibility of combing various impact factors of runoff into the model. The findings demonstrate that the data stream method provides a promising way to dynamically simulate runoff in a changing environment.

In this paper, compressive material tests on unconfined/confined resin and steel reinforced resin were experimentally evaluated in order to validate the numerical results. The uniaxial model which combines damage mechanics and Ramberg-Osgood relationship is proposed in this paper to describe the uniaxial compressive behaviour of resin and steel reinforced resin. Numerical homogenization is conducted to predict the tensile and shear behaviour of steel reinforced resin after validated by compressive material test results. The friction angle β , the ratio of the yield stress in triaxial tension to the yield stress in triaxial compression K, and the dilation angle ψ of the linear drucker-prager plastic model are obtained based on experiments and numerical homogenization simulation. The confinement effects on resin and steel reinforced resin could be effectively simulated by combing above parameters and uniaxial compressive model. Finite element simulations on unconfined/ confined resin and steel reinforced resin material tests were conducted to validate the material parameters proposed in this paper. A good agreement is observed, indicating the model and parameters proposed in this paper could be effectively used in the finite element simulation of injected bolts.