Main Structure Research Articles

Insight into adsorption of Pb(II) with wild resistant bacteria TJ6 immobilized on biochar composite: Roles of bacterial cell and biochar

Microbial immobilization is a new strategy for bio-remediation of heavy metals. However, information regarding immobilization of wild resistant bacteria onto biochar for heavy metal separation is limited. This study proposed the use of wild-resistant bacteria TJ6 in combination with biochar produced from agricultural waste (BC-TJ6) for Pb removal and investigated the associated mechanisms using Fourier transform infrared spectroscopy (FT-IR), energy dispersive spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). Compared with the theoretical adsorption capacity according to the linear combination calculating by the mass ratio and adsorption capacity of individual component in the composite material, the actual adsorption capacity of BC-TJ6 for Pb(II) was increased by 73.54%. Specifically, the bridge between the bacteria and biochar of Pb(II) may explain the higher observed adsorption capacity of BC-TJ6 compared to theoretical values. EDS analysis based on electron micrograph showed that Pb(II) adsorbed onto TJ6 strain was 0.48%, while that onto biochar component was 0.14%. It indicated that the resistant bacteria contributed more to the adsorption of Pb(II) in BC-TJ6 composites. The FT-IR analysis suggested that the amide, carboxyl, and hydroxyl groups on the surface of the composite were involved in the adsorption of Pb(II). Further, XPS analysis demonstrated that Pb-O (42.12%) and Pb-OOC (27.6%) were the main Pb-molecular structures bound to the surface of the composite. This study is significant for improving the understanding of biochar-wild resistant bacterial combinations for heavy metal adsorption, and can provide guidance for the use of biochar-microbial remediation of heavy metal pollution.

Comparison of single and multi-coolant axial jets on the temperature reduction of nose cone with multiple-row disk

Ensuring the thermal safety of the nose cone on high-velocity shuttles is crucial for maintaining the overall safety of hypervelocity vehicles. This study investigated the use of axial single and multiple jets to reduce the thermal loading on the main structure of the nose cone, specifically through the implementation of a multi-row disk. The research focused on analyzing the flow structure and shock interaction near the spike assembly by introducing a coolant sonic jet. Computational fluid dynamics was employed to simulate the compressible flow around the nose cone at a hypersonic flow regime, and the study comprehensively examined the impact of the jet position on the shock interactions and cooling mechanism of the spike and nose cone. The results specify that injecting the tip of the spike with a multiple-row disk is more effective in protecting the blunt body from thermal damage at hypersonic flow. Moreover, a comparison between single and equivalent multiple-jet systems revealed that the thermal performance of the multi-jet configuration is significantly superior to that of a single jet.

Seismic fragility analysis of rocking buckling-resistant braced structures subjected to far-field and near-field ground motions

To address the inadequate seismic performance of traditional buckling-restrained braced frame structures (BRBFS), this study introduces a novel structure, the rocking buckling-restrained braced frame structure (RBRBFS). The RBRBFS achieves effective control of main structure damage and enhances structural energy dissipation and seismic resilience by disconnecting the column feet from the foundation in the BRBFS and using friction energy dissipation devices as rocking column feet. This research aims to quantitatively assess the seismic performance and collapse safety margin of the new RBRBFS under different types of ground motions. To achieve this goal, two eight-story structures, one is traditional BRBFS and the other is RBRBFS, were designed. Incremental Dynamic Analysis (IDA) was employed, accounting for ground motion uncertainty, to conduct a comparative study of the seismic fragility of both structures subjected to near-fault pulse-like and far-field earthquake ground motions. Nonlinear dynamic analysis results indicate that under high-intensity ground motions, the RBRBFS significantly improves structural ductility and effectively controls structural damage. Compared to BRBF structures, the BRBFS exhibit a reduction of 26.5% and 18.3% in damage probability deviation under the two seismic excitations, highlighting their more stable structural response under varying seismic conditions. Furthermore, this novel RBRBFS increases the collapse margin ratio by 25% to 30%, demonstrating its higher seismic collapse resistance capacity

Regulating the multi-metal-sulfur bonds in the layered double hydroxide crystalline structure for rechargeable aqueous zinc batteries and supercapacitors

Layered double hydroxide (LDH) electrodes usually suffer from the limitations like unsatisfactory conductivity and electrochemical reversibility. Therefore, a novel and feasible method of introducing multi-metal-sulfur bonds in the main LDH crystalline structure, especially the Cu-S bonds, has been proposed and designed in this work. According to the experimental and theoretical analysis, the multi-metal-sulfur bonds could remarkably improve the electrochemical reversibility, activity and electrical conductivity of the LDH-based electrode. In addition, the designed material synthesis method could greatly enhance the specific surface area of the electrode, and via the subtle modulation of the copper and sulfur adulteration, the crystalline degree and the metal composition could be effectively adjusted. The prepared C/N-NiCoMnCu-LDH/S hollow structures (C/N-NCMC/S) possess a high specific capacitance of 1742 F g−1 at 1 A g−1 and could retain 68.6% of the capacitance at 20 A g−1. As for the assembled zinc battery, a specific capacity of 203.6 mAh g−1 could be achieved at 1 A g−1 and 74% of the capacity could be retained after 1500 cycles. Additionally, the hybrid supercapacitor delivers a super-long cycling stability of 98.1% capacitance retention after 40,000 cycles. Moreover, the battery and the supercapacitor present high energy densities of 127.2 and 41.4 Wh kg−1, respectively.

Fatal structure fire classification from building fire data using machine learning

PurposeThis study aims to develop a machine learning model to detect structure fire fatalities using a dataset comprising 11,341 cases from 2011 to 2019.Design/methodology/approachExploratory data analysis (EDA) was conducted prior to modelling, in which ten machine learning models were experimented with.FindingsThe main fatal structure fire risk factors were fires originating from bedrooms, living areas and the cooking/dining areas. The highest fatality rate (20.69%) was reported for fires ignited due to bedding (23.43%), despite a low fire incident rate (3.50%). Using 21 structure fire features, Random Forest (RF) yielded the best detection performance with 86% accuracy, followed by Decision Tree (DT) with bagging (accuracy = 84.7%).Research limitations/practical implicationsLimitations of the study are pertaining to data quality and grouping of categories in the data pre-processing stage, which could affect the performance of the models.Originality/valueThe study is the first of its kind to manipulate risk factors to detect fatal structure classification, particularly focussing on structure fire fatalities. Most of the previous studies examined the importance of fire risk factors and their relationship to the fire risk level.

Transdimensional ambient-noise surface wave tomography of the Reykjanes Peninsula, SW Iceland

SUMMARY Ambient noise seismic tomography has proven to be an effective tool for subsurface imaging, particularly in volcanic regions such as the Reykjanes Peninsula (RP), SW Iceland, where ambient seismic noise is ideal with isotropic illumination. The primary purpose of this study is to obtain a reliable shear wave velocity model of the RP, to get a better understanding of the subsurface structure of the RP and how it relates to other geoscientific results. This is the first tomographic model of the RP which is based on both on- and off-shore seismic stations. We use the ambient seismic noise data and apply a novel algorithm called one-step 3-D transdimensional tomography. The main geological structures in the study area (i.e. covered by seismic stations) are the four NE–SW trending volcanic systems, orientated highly oblique to the plate spreading on the RP. These are from west to east; Reykjanes, Eldvörp-Svartsengi, Fagradalsfjall and Krýsuvík, of which all except Fagradalsfjall host a known high-temperature geothermal field. Using surface waves retrieved from ambient noise recordings, we recovered a 3-D model of shear wave velocity. We observe low-velocity anomalies below these known high-temperature fields. The observed low-velocity anomalies below Reykjanes and Eldvörp-Svartsengi are significant but relatively small. The low-velocity anomaly observed below Krýsuvík is both larger and stronger, oriented near-perpendicular to the volcanic system, and coinciding well with a previously found low-resistivity anomaly. A low-velocity anomaly in the depth range of 5–8 km extends horizontally along the whole RP, but below the high-temperature fields, the onset of the velocity decrease is shallower, at around 3 km depth. This is in good agreement with the brittle–ductile transition zone on the RP. In considerably greater detail, our results confirm previous tomographic models obtained in the area. This study demonstrates the potential of the entirely data-driven, one-step 3-D transdimensional ambient noise tomography as a routine tomography tool and a complementary seismological tool for geothermal exploration, providing an enhanced understanding of the upper crustal structure of the RP.

Structural damage identification of high-order shear beams based on a genetic algorithm

The beam structure is the main load-bearing structure of engineering projects. High-order shear beams are widely used in engineering. Therefore, damage identification of beam structures is important to guarantee project quality and life safety. To identify the location and depth of cracks in a beam structure, a genetic algorithm (GA) and a damage identification model are combined. This method optimises the back-propagation neural network by using the ability of the GA to find the global optimal solution. The natural frequency (NF) of the cracked beam is obtained through finite-element analysis, and the NF is taken as the input of the model, and the crack location and depth are taken as the outputs of the model. In the experiment, it is found through regression analysis that the predicted output value of the model has a high coincidence with the real value, and its regression coefficient reaches 0.99842. Through an example analysis, the sum of squares of the prediction error of the model is 5.6. The average relative errors of the beam crack location and crack depth are 0.54 and 4.15%, respectively. The experimental results show that the proposed model has a high prediction accuracy and can accurately identify damage to the beam structure.

Risk factors for occurrence and progression of external auditory canal cholesteatoma

ObjectiveExternal auditory canal cholesteatoma (EACC) is characterized by retained squamous debris within the external canal and variable amounts of localized bone destruction. The etiology of primary EACC remains incompletely understood. This study was conducted to analyze the clinical features and backgrounds of patients with primary EACC and to clarify the risk factors for the occurrence and progression of EACC. MethodsSixty-nine ears of 62 patients diagnosed with primary EACC were included in this study (EACC group). Additionally, 74 ears of 60 patients with chronic otitis media (COM) with perforation who underwent tympanoplasty or myringoplasty were included as controls (COM group). We retrospectively investigated the clinical features, life history, and medical history of the patients in both groups. In addition, to investigate the risk factors for progression of EACC, we compared the clinical features and medical history of patients with stage IV (advanced) disease versus stage I + II (mild) disease. ResultsThe inferior wall of the bony canal was the main structure affected in patients with primary EACC of all stages. The following factors were significantly more common in the EACC than COM group: older age, female sex, left-sided disease, osteoporosis, renal dysfunction, anemia, and treatment with bisphosphonates. Among these, the most significant factor associated with EACC was renal dysfunction (odds ratio, 11.4; 95 % confidence interval, 2.32–55.9). The significant factors observed in patients with stage IV disease were younger age, male sex, posterior wall involvement, and otorrhea. Surgical treatment was required for more than half of the patients with stage III and IV EACC. ConclusionPatients with renal dysfunction are at risk of primary EACC. In particular, younger patients and relatively younger elderly patients with posterior wall involvement have a risk of progression to advanced-stage EACC. Canalplasty should be considered in patients with EACC who have these risk factors to prevent progression to advanced-stage disease.

Deep Learning-Based Microseismic Detection and Location Reveal the Seismic Characteristics and Causes in the Xiluodu Reservoir, China

ABSTRACT The Xiluodu reservoir, as the third reservoir developed in the lower Jinsha River, is the fourth largest reservoir in the world in terms of power generation. It is located in an area of historically high seismic intensity. A large amount of seismic activity has occurred in the reservoir area because the reservoir was impounded in 2013, but the mechanism of seismogenesis is still not clear. In this study, we collected continuous seismic records from July 2020 to October 2022 in the Xiluodu reservoir area, built a high-precision microseismic catalog for this region based on a deep learning seismic detection and location workflow called LOC-FLOW, and eventually obtained high-precision locations of 4924 earthquakes (five times more than the routine catalog). We sketched the main seismogenic structures based on the spatial and temporal distribution of the earthquakes in the catalog. According to the relationship between periodic variation of water level and seismic activity, seismicity in the reservoir area is active at the stage when the water level is filling to the highest point and starts to draw down. Especially, the sudden change in the rate of water level variation can easily trigger seismic activity. Combined with the spatiotemporal distribution of seismicity in each region and the previous results of numerical simulation, we concluded that the seismic activity in the reservoir head area and around the Manao fault is likely induced by the increase of normal stress and pore pressure diffusion caused by reservoir impoundment, whereas the ML 4.6 earthquake that occurred at the intersection of the Lianfeng fault and the Zhongcun fault was likely tectonic activity occurring on a concealed fault.

Tibial-Sling Triangular Medial Collateral Ligament Reconstruction With Posterior Oblique Ligament Limb

Background: While most medial-sided knee injuries can be managed conservatively, high-grade injuries of the posteromedial corner have been reported to have less than optimal outcomes with conservative approaches, resulting in residual valgus and rotational instability. Consensus among experts postulates that treatment should be based on reconstructing both the superficial medial collateral ligament (sMCL) and the posterior oblique ligament (POL). We present a modified technique of a tibial-sling anatomic MCL reconstruction with a POL limb. Indications: High-grade injuries of the posteromedial corner, specifically injuries with medial joint gapping in extension or grade 3 medial-sided tears. Technique Description: The MCL is reconstructed with a semitendinosus autograft in a tibial sling, created by converging perpendicular bone tunnels at its anatomic tibial insertion, and fixed to a femoral tunnel in the isometric point just posterior and proximal to the medial epicondyle with the knee at 30° of flexion. That same single femoral tunnel will be shared by the two strands of the semitendinosus graft and a limb of gracilis autograft to reproduce the POL, passed through a tibial tunnel in the posteromedial margin of medial tibial condyle, and fixed in extension. Discussion/Conclusion: As recent evidence suggests that medial reconstruction should be preferred over repair, due to favorable complication and failure rates, we describe a technique that is both anatomic-based, reproducing the 2 main medial knee structures (sMCL, POL), and also cost-saving, with decreased need of fixation devices. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Cavity detection using a pseudo-3D electric resistivity tomography at the Palaeolithic/Neolithic site of Scaloria Cave, Apulia, Italy: integrated assessment of synthetic and field data sets

A pseudo-3D electrical resistivity tomography (ERT) survey has been carried out to detect cavities at the Neolithic/Palaeolithic site of Grotta Scaloria, close to Manfredonia, Apulia, Italy. Scaloria Cave has a rich history of archaeological research of more than 80 years and is one of the most important Neolithic complexes in the Mediterranean. Synthetic data modelling allowed to check the adequacy of the geophysical method and to develop a proper experimental setup at the survey design stage. Indeed, the results of the field data inversion revealed high resistivity anomalies which can be related to cavities and provided a good definition of the main geological structures and boundaries. Moreover, the results suggest that unknown and speleological unexplored cavities are still present at the Scaloria Cave study site. These findings may provide further insights on pseudo-3D ERT applicability, particularly for cavity detection. Furthermore, the approach used in this study yields fruitful information for further archaeological survey design and for the interpretation of ERT investigations targeting similar geological features and structures.

Experimental Study on Wind Load and Wind-Induced Interference Effect of Three High-Rise Buildings

Wind loads of high-rise buildings are a key parameter in architectural design. The magnitude and distribution characteristics of wind loads are of great importance for the safety and economy of structural design. The wind loads of high-rise buildings are quite different from those of monomer buildings. The wind-induced interference effect could significantly increase the local wind pressure of buildings, causing potential safety hazards for the main structure and enclosure structure. For the three common high-rise buildings, we adopted the wind tunnel test method to measure the surface pressure of each building. The corresponding Re number was 8.2×106. This paper studied the shape coefficients, fluctuating wind pressure coefficients and base bending moment coefficient of each building with different wind direction angles and different spacing ratios, and the maximum value of each parameter and the corresponding working condition were statistically analyzed. The results showed that, under any wind direction angle, the fluctuating wind pressure coefficients on all sides of the building were affected by the spacing ratio, and the fluctuation range was large. When the wind angle was 180º, the fluctuating wind pressure coefficients on the sides of Building 1 were most affected by the slope ratio. At this wind angle, the maximum value was 0.43 at a slope ratio of 5.0, which was 65% different from the minimum. Partition shape coefficients of some sides and top surfaces changed significantly with the spacing ratio. When the spacing ratio was 5.0, the base bending moment coefficients in the downwind and crosswind directions reached their maximum values, and the wind direction angles where the maximum values of the base bending moment coefficients in the downwind direction were 40º and 50º, respectively, and the wind direction angle where the maximum value of the base bending moment coefficients in the crosswind direction was 10º. Due to the influence of the wind angle and the building spacing ratio, the wind loads on the facades of the pyramidal group of buildings varied greatly, and the wind-induced interference effect was evident. The wind load between the building facades in the three buildings was different, and the wind disturbance effect was evident. Therefore, the most unfavorable stress state and interference state of the structure should be comprehensively considered in the wind resistance design of the three buildings. The building spacing ratio should preferably be set to 3.0, and wind angles of 10º, 40º, and 50º should be avoided whenever possible.

Multi-View Fuzzy Classification With Subspace Clustering and Information Granules

Multi-view learning becomes increasingly attractive and promising because multimodal or multi-view data are commonly encountered in real-world applications. In this study, we develop a novel multi-view Takagi-Sugeno-Kang (TSK) fuzzy system framework to handle classification problems for such data. We propose an anchor and graph subspace clustering strategy to discover and represent the actual latent data distribution for each view separately. In this way, the discriminate anchors (landmarks) are learned to capture the main structure of the multi-view data. This strategy also provides a computationally efficient clustering algorithm with respect to the number of instances. These resulting anchors are formed as the prototypes of information granules (IGs) for fuzzy modeling. Then we construct an information-granule-based multi-view TSK fuzzy classification model inherited from the natural interpretability of fuzzy rule-based systems. Concretely, the relationship between the multi-view input and label output spaces is depicted by IGs-oriented fuzzy rules. The experimental studies involve various commonly used benchmark datasets, which indicate that our proposed method achieves comparable or better performance compared to the state-of-the-art algorithms.

The influence of surface effects on axisymmetric vibration of graded porous Mindlin circular nanoplate in a temperature field

AbstractThe surface effect significantly affects the mechanical response of nanoscale materials. In this work, we introduce Gurtin‐Murdoch surface elasticity theory into Mindlin plate theory to study the axisymmetric vibration characteristic of graded porous circular nanoplate in a temperature field. The main structure is a porous graded material with uniform or non‐uniform porosity distribution in its thickness. The numerical shooting technique was applied to solve the governing differential equations derived from Hamilton's principle. Responses for the vibration characteristic of the graded porous nanoplate for both clamped and simply supported boundary conditions were obtained. The numerical results show that when the surface effect is removed, the classical results of Mindlin circular plate will be obtained. Natural frequencies and mode shapes varying with thermal and porosity coefficients were present graphically. And then the effects of surface material properties on the axisymmetric vibration characteristic of the nanoplates were discussed in detail. The parametric study examined the influence of porosity coefficient, porosity distribution mode, surface elastic parameters, and residual surface stress on the vibration characteristics of porous circular nanoplates.

Mimosa tannin based NIPU wood adhesive with significant substitution of hexamethylenediamine using polyethyleneimine

Tannin-based non-isocyanate polyurethane (NIPU) adhesive exhibits an excellent performance for wood bonding, but contains excess toxic hexamethylenediamine (HMDA), which is emitted to the environment during the preparation of wood panels. Herein, branched polyethylenimine (PEI)/tannin mixtures were utilized to share this adhesive in one integral formulation via various additions at the expense of HMDA. The physical properties, including pH, non-volatile content, viscosity, tannin- and bio-sourced-contents were investigated and compared to a traditional NIPU. The results have shown that the viscosities of the modified adhesives were increased significantly, with improvements at about 2–5% of bio-sourced content and around 4–8% of tannin content being achieved. Moreover, the HMDA content was decreased from 31 % for control T-NIPU-0-0 adhesive to 19 % for the modified adhesives. Possible undergoing reactions of the tannin-NIPU based adhesives series was investigated by Fourier transform infrared spectroscopy (FT-IR) and 13C nuclear magnetic resonance (NMR) analyses. The main tannin-based NIPU structure was maintained even after tannin/PEI mixtures were added. Thermomechanical analysis (TMA) results showed two typical curing stages for either the control adhesive (T-NIPU-0-0) or the modified ones, but different curing performance was observed for modified adhesives, particularly at the first stage. The thermal stability of the modified adhesives was enhanced due to the inserted tannin/PEI mixture, which was proven by thermogravimetric analysis (TGA). The mechanical properties indicated that formulations with suitable weight ratios of tannin/PEI mixtures, such as T-NIPU-4-1 and T-NIPU-5-1 adhesives, could hold a similar performance to the control T-NIPU-0-0 adhesive, which satisfied the European Norm EN 312–2010 for 12- mm boards of type P2. Moreover, a small addition of glycerol diglycidyl ether (GDE) into the T-NIPU-4-1 adhesive endowed an acceptable bonding performance while undergoing different preparation conditions. Therefore, the modified adhesives with the branched PEI/tannin adduct inherited outstanding bonding performance compared to classical tannin-NIPU adhesives along with a noteworthy decreased release of harmful substances such as HMDA, which is in line with the requirements for a cleaner production process.

The Malay Tale of The Pig King (2015): An Adaptation of Hikayat Raja Babi (1775)

Hikayat Raja Babi is an old Malay manuscript written in 1775 by a Semarang merchant named Usup bin Abdul Kadir while sailing to Palembang. It was handwritten in Jawi script and is in the collections of The British Library where it has been digitised, making it freely accessible by all. In 2015, Buku Fixi, a Malaysian publishing company, transliterated the manuscript and published a Romanised version of Hikayat Raja Babi. In 2020, the story was reproduced and published by Matahari Books as an illustrated storybook. This article discusses the adaptation of Hikayat Raja Babi into the version of The Malay Tale of the Pig King. The two texts are analysed based on Hutcheon’s theory of adaptation. Findings show that The Malay Tale of the Pig King has been adapted and simplified through appropriation process, making it suitable for young readers. The latter version still maintains the main story structure by having the same key events as in the original storyline. In addition to this, beautiful illustrations on the cover of the book and throughout the entire book makes The Malay Tale of the Pig King visually appealing.

Floral, reproductive, and pollination biology of Floral, reproductive, and pollination biology of Eugenia myrcianthes Nied.

Studies on species of the family Myrtaceae are mostly related to floristic surveys, reproduction involving large plant communities, and family taxonomy. Thus, the objective of this study was to elucidate aspects of the floral and reproductive biology, as well as floral visitors of ubajai (Eugenia myrcianthes Nied.). Studies were conducted on floral morphology and morphometry, identification of nectaries and structures attractive to floral visitors, characterization of floral visitors, stigma receptivity, and androecium maturation, pollen storage, in vitro viability testing, and characterization of the reproductive system. Ubajai flowers open at approximately 6:00 a.m., and their anthers are the main attractive structure to floral visitors. The main floral visitors and effective pollinators of ubajai are honeybees (Apis mellifera). The addition of 40% sucrose to the culture medium, using fresh pre-anthesis pollen, allows for a 90% germination rate. Ubajai pollen is recalcitrant, thus, it loses viability before 30 days of storage, even when stored in a refrigerator, freezer, liquid nitrogen, or natural environment. Ubajai can be considered a self-compatible plant; however, fertilization of flowers through cross-pollination also occurs, and apomixis does not occur.

Clinical findings in patients with vertebrobasilar insufficiency

The vertebrabasilar (VB) system plays an essential role in the circulation of main structures of nervous system. As a part of Circle of Willis, it is responsible for major compensatory abilities of brain circulation in some hemodynamic disorders. On the other hand, some pathological diseases, involving VB system, could be fatal or could lead to severe injuries and functional wastes in the patient. Many variations and anomalies in VB system are common cause of hemodynamic disorders and vascular disease such as atherosclerosis. The good knowledge of variations and anatomy as well, allows us to understand pathophysiology and pathogenesis in those disorders, which in combination with specific clinical symptoms, helps us in making the fast and accurate diagnosis. This is fundamental for starting proper treatment.

Experimental investigation of a dual-pontoon WEC-type breakwater with a hydraulic-pneumatic complementary power take-off system

Floating offshore multi-purpose structures have recently attracted much attention worldwide in terms of sharing costs, enhancing efficiencies and reducing environmental impacts. In this paper, hydrodynamic experiments are conducted to examine the accessibility of wave energy absorption by a dual-pontoon floating breakwater integrated with hybrid-type wave energy converters (WECs). The main structure and the air chamber between the two pontoons are designed as an Oscillating Buoy (OB) and an Oscillating Water Column (OWC), respectively. Two power take-off (PTO) systems, including a hydraulic system and a Wells turbine, are selected to extract wave energy from structural motion and chamber airflow. To investigate the hydraulic-pneumatic complementary effects, PTO damping coefficients of two systems are adjusted both individually and synchronously. Besides, the hydrodynamic comparison among different geometrical parameters, are further studied. The breakwater-integrated hybrid WEC system led to a larger optimal pneumatic damping for the OWC while the optimal hydraulic damping for the OB is not affected. Additionally, the internal air pressure is acting as a resistive force to pontoons, hence the pontoon motion is smaller, and part of the kinematic energy from pontoons is extracted by the OWC. Correspondingly, the wave attenuation capacity is enhanced by multiple harvesting manners, especially for long-period waves.

Exploring the structure of micro topics in Chinese language and literature based on the fusion of multiple features

Abstract In this paper, firstly, the topic structure of the Chinese language and literature is explained, and the micro topic structure representation system is constructed by using the main statement bit structure theory and the main bit advancement model. Secondly, the word2vec network is used to extract the features of Chinese language and literature elements, and a multi-feature fusion classification recognition model is constructed based on SVM. Finally, the corpus was used to validate the example. The results show that the percentage of radial primary advancement pattern of micro topic structure is the highest and reaches 94.13%, and the recognition accuracy of SVM-based multi-feature fusion recognition classification model for micro topic structure is improved by 12.04%, 18.29% and 7.45% respectively compared with BTM algorithm, LDA algorithm and K-means algorithm.