Base Angle Research Articles

Craniofacial development in patients of Tessier No.0 cleft with a bifid nose using 3D computed tomography.

ObjectiveConsiderable studies have focused mainly on the facial deformity of Tessier No.0 cleft with a bifid nose, but the deformity of the skull is not well understood. Therefore, our study aimed to explore the evolution of cranial dysmorphology and the chronology of Tessier No.0 cleft with a bifid nose, by three-dimensional measurements.MethodsNinety-six non-surgical patients and computed tomographic scans were included (Tessier No.0 cleft with a bifid nose, n = 48; controls, n = 48) and divided into five age subgroups. Craniofacial cephalometric measurements were analyzed by Mimics software.ResultsThe widening of nasal bone was the most remarkable and persistent from 2 years old appropriately. The overall cranial base length in patients compared with controls increased 11.8% (p < 0.01) on average. The middle and posterior cranial fossa increasing accounted for most of this change. The cranial base angles also showed increased obviously. By analyzing the linear of the nasopharynx and respiratory tract, it was found that its development did not affect respiration.ConclusionsThe cranial base deformity of Tessier No.0 cleft with a bifid nose consists of the whole skull base and particularly the middle and posterior cranial base length increase. At the same time, there may be late closure of the spheno-occipital synchondrosis and sella displacement. We believe this study is unique in providing valuable data for elucidating the pathological and morphological abnormalities of skull base development in Tessier No.0 cleft with a bifid nose.

Minimally Invasive Method in Treatment of Idiopathic Congenital Vertical Talus: Recurrence is Uncommon.

Historically, treatment for congenital vertical talus (CVT) has included open reduction of the talonavicular joint and extensive soft tissue release. In 2006, a new minimally invasive method consisting of serial manipulation and casting followed by percutaneous fixation of the talonavicular joint and percutaneous Achilles tenotomy was introduced. Although the early results of this new technique are promising, more research is needed to verify that the talonavicular correction is maintained with time. We conducted a retrospective chart review of all patients with idiopathic CVT who underwent minimally invasive correction by a single surgeon at a tertiary care institution. Radiographic evaluation of the preoperative, immediate postoperative, 1 year postoperative and latest follow-up appointments were performed. Complications and clinical outcomes were recorded. Radiographic recurrence of the deformity was defined as lateral talar axis-first metatarsal base angle >30 degrees. Statistical analysis was performed on the maintenance of radiographic correction and factors associated with recurrence. Forty seven feet in 35 patients were included in the study with average follow-up of 45 months. The average preoperative lateral talar axis-first metatarsal base angle was 74±18 compared with 12±8 after initial surgical intervention. In addition, radiographic correction of all other measured angles was achieved in every child following the initial surgery. Radiographic recurrence of talonavicular deformity was seen in 4 feet (9%). No cases of recurrence required a second corrective surgery during the follow-up period. There was a significant association between patient age at the time of treatment and recurrence of talonavicular deformity with patients older than 12 months being more likely to experience recurrence ( P =0.041). In this large series, we found that correction of talonavicular deformity can be achieved and maintained in a large majority of children with idiopathic CVT who undergo treatment with this minimally invasive technique and recurrences are uncommon. Treatment with this technique should be initiated as soon as a diagnosis of CVT is confirmed and the patient is medically stable to decrease the likelihood of experiencing recurrence of talonavicular deformity. Level III.

Comparative analysis of the leaf architectural characters of Saurauia bontocensis Merr. and Saurauia polysperma (Blanco) Merr. with the application of Digital Image Analysis Software

Abstract. Daipan BPO, Buot IE Jr., Daipan HMO. 2022. Comparative analysis of the leaf architectural characters of Saurauia bontocensis Merr. and Saurauia polysperma (Blanco) Merr. with the application of Digital Image Analysis Software. Biodiversitas 23: 3869-3875. Major confusion still exists among several authors concerning the taxonomy of the dagwey plant. This species is economically significant to the Ikalahan tribe of Luzon, Philippines. Several papers claimed that the plant is Saurauia bontocensis, while others stated that it is Saurauia subglabra. Many botanical websites claimed that S. subglabra is synonymous with S. polysperma, while another article distinguished S. subglabra from S. polysperma. Thus, to help resolve the taxonomic ambiguities, this paper performed a comparative analysis of the leaf architectural characters of S. bontocensis and S. polysperma with the aid of digital image analysis software and cluster analysis. Results revealed that the blade characters alone, delineate the two species, particularly, in terms of the laminar size, shape, symmetry, leaf L:W ratio, base and apex angle, and base shape. Additionally, the leaf venation characters delineate the two species, specifically, on the 2º to 5º vein categories, 2º vein angle, 3º vein course, 3º vein angle to 1º, areolation, freely ending ultimate veins, marginal ultimate venation, and leaf rank. Generally, S. bontocensis have larger, longer, and wider leaves compared with the S. polysperma. The leaf architecture analysis performed in this paper produced a very promising result in differentiating the two Saurauia species and could be used to address some of the taxonomic confusion of these species. The study indicated that S. bontocensis and S. polysperma are two distinct species. Moreover, the use of digital image analysis software was very helpful in the computations of the various blade characters, particularly the digital herbarium exsiccate in the absence of actual leaf samples.

Analysis of Inferior Nasal Morphology and Nostrils following Le Fort I Osteotomy.

This study aimed to investigate the soft tissue parameters related to inferior nasal morphology and nostril shape and investigate the change at nostril types according to the Modified Topinard System following maxillary surgery. Thirty-five patients who underwent Le Fort I osteotomy with or without mandibular osteotomy were included in this retrospective study. Presurgery (T1) and postsurgery (T2) measurements which were the angle between the longitudinal axis of left and right nostril, nostril length, nostril width, alar width, alar base width, columella length, and columella width, were measured on computed tomography images. Nostril types according to Modified Topinard System and nostril shapes were also examined. Following Le Fort I surgery, there was a significant increase in alar base width, alar width, and angle between the longitudinal axis of the left and right nostril (P<0.05). Nasal tip protrusion was decreased with significance (P=0.022). Multiple linear regression analysis showed that every 1mm maxillary impaction amount leads to a 3.34° increase in the angle between the longitudinal axis of the left and right nostrils (P=0.03, adjusted R2=0.21). Nostril type classification according to Modified Topinard System was changed significantly (P=0.000). Surgeons should be aware of the risk of postoperative nonaesthetic results in Modified Topinard System's borderline cases. Modified Topinard classification may be included in preoperative orthognathic planning from the bottom view.

An analytical investigation on characterizing the properties of glass composition for crystalline silicon solar cells based on the digital microsystem measurement technology

As a significant component of silver paste, glass frit has a nonnegligible effect on crystalline silicon solar cells. The purpose of this research is to obtain an analysis method to explore the performance of glass frit for solar cells. The samples were measured by digital microscopic system, and the three-dimensional layered tinting model was established. Moreover, the longitudinal cutting was carried out. The data of cross section was analyzed to obtain the information of melt height, wetting base angle, and melting included angle, to further infer the relationship between thermal stability, fluidity, wettability with mathematical model of glass frit through theoretical derivation. The curve fitting method was introduced in detail and the law was summarized. Based on relationship of them, the melting characteristics of glass frit could be quantitatively tested. The vertical view and surface topography were measured by the digital microscope and found that the glass frit underwent shrinkage, softening, wetting, spreading, and equilibrium during sintering. Combined with the image, abundant information was detected from the macroscopic structure of glass surface. Meanwhile, the mechanism of spreading was explained. Finally, the screen-printing technology combined with the 3D microscopic view of the silver grid line proved that glass frit with satisfactory performance can effectively reduce the contact resistance of solar cells, improve the photovoltaic conversion efficiency, verify the feasibility and accuracy of the simulation method equally. This study not only enriches the understanding of glass frit for crystalline silicon solar cells, but also provides a theoretical guidance for the research and determination of its performance. • Digital microscope system was used to record the shape changes of glass samples and more wetting parameters. • This investigation used a combination of mathematical simulation and physical simulation. • The essence of the technology to characterize glass is to combine the fixed droplet technology with optical measurement.

Cranial base flexion in young adults belonging to the South Indian population – A cross sectional study

Objectives: The aim of the study was to determine the cranial base flexion in the South Indian population. The objective was to establish norm values of the various cranial base angles namely N-S-Ba angle, N- S- Ar and PCF/PM angle and to determine if there was any difference in these measurements between male and female … Continued

Characterization of Common Bean (Phaseolus vulgaris L.) Genotypes for Drought Tolerance

Background: Drought is a major constraint affecting the seed yield of common bean in smallholder farmers’ fields in Malawi. Therefore, there is a need to develop genotypes that can perform well under drought conditions. The study was conducted to assess the variability of common bean genotypes under stressed and optimum soil moisture conditions. Methods: Forty-three common bean genotypes were evaluated under low and optimum soil moisture in a split-plot pot experiment in 2017. Data were collected at flowering stage on five root traits and seed weight. Result: Highly significant (P less than 0.01) differences were observed among the genotypes and the genotype × water treatment interactions for the root traits and seed weight. Water stress increased hypocotyl root number, basal root number and basal root growth angle by 127.1, 11.3 and 46.1% respectively, while hypocotyl root length, basal root whorl number and seed weight were reduced by 7.1, 1.9 and 9.4% respectively. Broad sense heritability and genetic advance (%) was highest for hypocotyl root length. Genotypes CER-78, SAB-560 and SER-125 were considered tolerant to soil moisture stress and should therefore be tested in various drought conditions for release and used for genetic enhancement focusing on root traits and seed yield.

Craniofacial Morphologic Predictors for Passive Myofunctional Therapy of Pediatric Obstructive Sleep Apnea Using an Oral Appliance with a Tongue Bead.

We conducted this retrospective study to identify potential clinical, polysomnographic, and cephalometric predictors for the treatment outcomes of a tongue-beaded oral appliance (OA) in children with obstructive sleep apnea syndrome (OSAS). In total, 63 patients—50 boys and 13 girls ranging in age from 4 to 16 years—underwent OA treatment nightly for at least 6 months. A baseline digital lateral cephalometric radiograph was obtained for each patient. Multivariate logistic regression analysis was performed to examine predictors for the treatment outcome based on the clinical and cephalometric measurements. Overall, 28 patients responded to the treatment (post-treatment improvement > 50% or apnea–hypopnea index (AHI) < 1/h), and 35 did not (post-treatment improvement < 50% and AHI ≥ 1/h). Significantly larger cranial base angle (SNBa), smaller lower gonial angle (LGo Angle), and shorter length of anterior cranial base (SN) were found in responders. Smaller lower gonial angle (LGo Angle) and smaller anterior cranial base (SN) predict a favorable outcome for pediatric OSAS using a tongue-beaded OA. This finding will equip practitioners with additional insights when selecting suitable candidates for OA therapy in pediatric patients.

Dynamics of nanoscale triangular features on Ge surfaces

Ion beam sputtering, known as potential technique for producing nanoripple on various surfaces having wide range of applications. Along with nanoripple, triangular features are also superimposed, limiting their use for some potential applications. Here we are reporting evolution of triangular features on Ge (100) surfaces under low energy (300–1000 eV) Xe ion irradiation at room temperature for angles of incidence (61°–80°) and ion fluences of (5.34 × 1017−8.01 × 1018 ions cm−2). Triangular features appear with the onset of ripple formation and disappear when the ripple periodicity is lost. These features formation depend not only on material but also depend on the ratio of the ion/target mass. In comparison with numerical simulations based on modified anisotropic Kuramoto-Sivanshinsky equation, we find good agreement for the evolution of base angle and lateral length for the triangular features with ion incidence angle. The dynamics of triangular feature with ion incidence angle and ion fluence have been reported. Ion-incidence angle dependency is adequately replicated in numerical simulations. Experimentally the base angle and lateral length increases with increase in ion incidence angle, similar trend is observed in numerical simulation.

A new indirect magnetic resonance imaging finding in anterior cruciate ligament injuries: Medial and lateral meniscus posterior base angle.

Objectives This study aimed to define the medial meniscus posterior base angle (MMPBA) and the lateral meniscus posterior base angle (LMPBA) measured in the medial and lateral meniscus posterior horns and examine the biomechanical and morphological relationship between anterior cruciate ligament (ACL) injuries and posterior meniscus horns using these parameters.Patients and methods The retrospective study was conducted with 32 patients with ACL rupture and 40 control patients, for a total of 72 patients (40 males, 32 females; mean age: 36.3±9.9 years; range, 18 to 57 years), between January 2016 and January 2018. The posterior tibial slope (PTS) was measured in standard radiographs, and MMPBA and LMPBA values were assessed by standard knee magnetic resonance imaging. The MMPBA was defined as the angle between the line passing through the medial meniscus’ tibial side border and the line passing through the capsular side border in the sagittal section's medial meniscus posterior horn. The LMPBA was defined as the angle between the line passing through the lateral meniscus' tibial side border and the line passing through the capsular side border on the sagittal section's lateral meniscus posterior horn. Groups were compared for PTS, MMPBA, and LMPBA.Results When both groups were compared in terms of MMPBA and LMPBA, patients with ACL rupture had significantly higher base angles (p<0.001 and p=0.031, respectively). The mean MMPBA was 84.27º±12.59º (range, 62º to 106.1º) in patients with ACL rupture, while it was 70.75º±7.85º (range, 55.1º to 88.6º) in the control group. The mean LMPBA was 83.62º±11.4º (range, 62.3º to 105.9º) in patients with ACL rupture, while it was 76.94º±11.46º (range, 30.8º to 96.5º) in the control group. In the receiver operating characteristics curve analysis, the cut-off value of MMPBA was 84.5, and values above this showed a 58.5% sensitivity and a 97.6% specificity for ACL rupture, whereas for LMPBA, the cut-off value was 93.15, and values above this showed a 27.3% sensitivity and a 95.1% specificity for ACL rupture. The PTS and MMPBA were significantly correlated with each other (p=0.047). The MMPBA and LMPBA were also significantly correlated with each other (p=0.011). However, there was no significant correlation between PTS and LMPBA (p=0.56).Conclusion Medial meniscus posterior base angle and LMPBA values above 84.5º and 93.15º, respectively, are new indirect magnetic resonance imaging findings of ACL injury.

Morphology of the coracoid process as a predictor of articular-side tear at the upper border of the subscapularis.

Articular-side tear at the upper border of the subscapularis (SSC-AST) is often detected during shoulder arthroscopic surgery, although its exact pathology remains unknown. The purpose of this study was to investigate the correlation between various characteristics of the coracoid process, including classification of the morphology of the coracoid process tip, and the presence of SSC-AST. This retrospective, case-controlled study included patients who underwent arthroscopic subacromial decompression with or without rotator cuff repair between January 2018 and September 2021. A total of 130 shoulders in 124 patients, including 77 male and 53 female shoulders (mean age at surgery, 64 years [range, 39-88 years]), were included in this study. Three-dimensional (3D) computed tomography examination was performed preoperatively, and the following indices were measured: coracoid proximal length, coracoid distal length, coracoid angle, coracoglenoid angle, offset of the coracoid process and glenoid (anterior, lateral, and superior offset), and coracoid base angle. The morphology of the tip of the coracoid process was classified into 3 types according to 3D reconstructed views: flat type, round type, and beak type. The presence of SSC-AST was intraoperatively evaluated arthroscopically via a posterior glenohumeral portal. Morphologic risk factors for SSC-AST were evaluated between SSC-AST cases (group T) and non-SSC-AST cases (group N) by multivariable logistic analysis. In addition, the correlation between the incidence of SSC-AST and classification of the tip of the coracoid process was analyzed. SSC-AST was present in 53 shoulders (40.8%). Group T patients were significantly older than group N patients (68.4±10.0 years vs. 61.5±11.8 years, P<.001). No sex difference was detected between the 2 groups (28 male and 25 female shoulders in group T vs. 49 male and 28 female shoulders in group N, P=.28). Multivariate analysis of morphologic parameters between the 2 groups detected a smaller superior offset as a risk factor for SSC-AST (odds ratio, 0.91; 95% confidence interval, 0.84-0.98; P=.01). No significant differences were found in the other parameters. Regarding classification of the tip of the coracoid process, round- and beak-type coracoid tips had a significantly higher rate of SSC-AST than flat-type tips (flat type, 21.8%; round type, 64.7%; and beak type, 46.3%) (P<.001). Evaluation of the correlation between the morphology of the coracoid process on 3D computed tomography and the presence of SSC-AST visualized during arthroscopy indicated a significant association between SSC-AST and the morphology of the coracoid process.

Are There Differences in the Cranial Base of Humans and Apes?

Differences in skull-base angles between humans, other hominid species and apes might account for the ability of humans to develop complex speech. This study compared midline skull base angles, and angles related to insertion of skull base musculature between these species. 126 human adult, 29 adolescent, 19 children, and 13 fetus skulls were compared to 32 ape and a subset of non-human antiquity hominid casts of skulls (13). Cranial base measurements were taken using an eMicroscribe 3d G2 digitizer. Midline and muscle insertion measurements were obtained. There were statistical differences in both the midline angles of the skull base (humans, 119o; apes, 130o) and in the Skull base angles related to points of muscle insertion (humans, 113o; apes, 124o), with humans exhibiting a more acute angle than the apes and other non-human hominids. There were no differences between human adults and children CONCLUSION: Acute angle differentiation of the midline skull base between humans and apes was confirmed with an alternate measurement method. Whether these angular differences are the primary reason for the lower position of the larynx in humans and the potential for more complex speech is still in debate.

Analysis of supercritical heat transfer in horizontal helical tube with internal roughness

• Supercritical flow in horizontal helical tube with internal roughness is analyzed. • Circumferential non-uniformity and axial oscillation of T w are explored. • The internally ribbed roughness and concaved roughness are compared. • The effects of spiral roughness, centrifugal force, and buoyancy are revealed. Helically coiled tube with smooth wall (HSW) has been widely used in the fields of supercritical air conditioning systems and supercritical heat pump systems due to its compact structure and excellent heat transfer performance. However, its large circumferential non-uniformity and intense axial oscillation will bring to local stress concentration and instability of heat transfer which are both responsible for system accidents. To alleviate the above two crises, the spiral inner wall roughness is proposed to be introduced into HSW. Up to now, the performance of helically coiled tube with internally ribbed roughness (HRW) has been seldom reported and the effectivenesses of inner roughness with different structures on suppressing circumferential non-uniformity and axial oscillation are still unclear. In this work, the SST k - ω model is employed to simulate the turbulent flow of s-R1234ze(E) in horizontal HRW to fill these gaps. Firstly, the effectivenesses of different rib heights, rib lift angles, rib widths, rib numbers, and rib base angles on restraining circumferential non-uniformity and axial oscillation are explored. The influences of wall thickness are also contained. Subsequently, the internally ribbed roughness and concaved roughness are compared and evaluated according to the overall comprehensive performance criterion. Finally, the effects of spiral roughness, centrifugal force, and gravitational buoyancy force on the flow field distributions are also revealed.

Evaluation of the Basal and Sphenobasion angles using CT Scan in the Iranian population

Objectives: This study aimed to find the difference in the values of the cranial base angles among Iranian adults and investigate the relationship between the Basal and Sphenobasion angles.&#x0D; Methods: 100 individuals (50 males and 50 females) aged between 18 to 60 participated in this cross-sectional study which was carried out from September 2018 to September 2019 in the imaging centers affiliated with the Faculty of Medicine, Tehran University of Medical Sciences and Basal and Sphenobasion angles were measured in all of the participants.&#x0D; Results: A significant correlation was observed between age and Sphenobasion angle in the male group (P= 0.0001, r= 0.439), but no positive relation was observed between Sphenobasion angle and age in the female group (p=0.309). The results of this study exhibited the significant relations between the Basal and Sphenobasion angles in the females and males (P= 0.001, r= 0.396 and P= 0.0001, r= 0.534 respectively).&#x0D; Conclusion: This study showed positive correlations between the Basal angle and age in the females and males and significant relations between the Basal and Sphenobasion angles in the two genders.

Light trapping PMMA planar ridged waveguide on a laser textured silicon substrate for ultra-low reflectivity

A novel composite total internal reflectance fiber structure on monocrystalline silicon (mono c-Si) constructed by specific micro-structures with base angle of 55 degrees and closely nested PMMA film is innovatively proposed to achieve a more effective sunlight trap for the first time. Besides the trapped light caused by multiple reflections on the laser textured surface, the total internal reflectance effect of light on the exiting surface of PMMA film is realized, which gains more times of reflection and absorption among the composite structure and further improves the anti-reflection effect. It’s found the reflectivities of the composite structures containing regular pyramid and V-shaped micro-structures have notably decreased to under 1.45% and 2.60% respectively in wavelength range of 350–1000 nm. This composite structure provides a new alternative and effective approach for the design and fabrication of silicon surface with ultra-low reflectivity.

Influence Rule of Annular Notch Geometric Parameter on the Tubing Surface: A Case Study

In regards to the problem of tubing precision separation, the high-efficiency precision separation method for tubing under eccentric wheel high-speed rotational bending fatigue loading is proposed, which aims to promote the initiation of fatigue cracks at the root of the annular V-notch on the tubing surface. Research on the stress concentration effect of the annular notch on the tubing surface is carried out. The design of the notch takes into account the characteristics of tubing precision separation. The numerical simulation calculation includes four kinds of notches, namely, annular V-notch, annular U-notch, asymmetric V-notch towards the blanking end direction 45°, and asymmetric V-notch away from the blanking end direction 45°. The crack propagation lengths produced by each notch under the same experimental conditions are investigated experimentally. According to the findings, the annular V-notch is suitable for this separation method. By analyzing the theoretical stress concentration factor of the annular V-notch on the tubing surface, three main parameters affecting the annular V-notch root stress field are determined, namely, notch angle, notch depth, and notch root base angle radius. Through calculation and analysis, the influence law of tubing annular V-notch angle, notch depth, and notch root base angle radius on the stress concentration effect is obtained. Based on the process characteristics of tubing precision separation, the ideal tubing annular V-notch geometric parameter is presented within a reasonable value range. For the validation experiment of tubing precision separation, 45# steel, 304 stainless steel, and T2Y copper tube are selected, respectively. Finally, a great tubing precision separation effect is achieved, which verifies the reasonable selection of the tubing surface annular V-notch geometric parameter.

Unsteady dynamics in a subsonic duct flow with a bluff body

A series of reduced-order numerical simulations on a specific bluff body type (v-gutters) in a subsonic duct flow is performed to assess the unsteady wake dynamics. Two of the v-gutter's geometrical parameters are varied: the v-gutter's base angle (θ) and the size of a slit (ξ) at the leading-edge of the v-gutter. Turbulent flow kinematics and pressure field are analyzed to evaluate the unsteadiness at a freestream Mach number of M∞=0.25 and a freestream Reynolds number based on bluff body's transverse length (L = 17.8 mm) of ReL=0.1×106. Five v-gutter angles are considered (θ, rad=π/6,π/4,π/3,5π/12,π/2) and three slit sizes (ξ, mm =0,0.25,0.5) are considered only for a particular θ=[π/6]. In general, high fluctuations in velocity and pressure are seen for the bluffest body in consideration (θ=π/2) with higher drag (cd) and total pressure loss (Δp0). However, bluffer bodies produce periodic shedding structures that promote flow mixing. On the other hand, the presence of a slit on a streamlined body (θ=π/6) tends to efficiently stabilize the wake and thus producing almost a periodic shedding structure with lower cd and Δp0. For θ=[π/6], broadened spectra in vortex shedding are seen with a peak at [fL/u∞]∼0.08. For θ≥[π/4], a dominant discrete shedding frequency is seen with a gradual spectral decay. Similarly, the effects of ξ on the θ=[π/6] case produce a discrete shedding frequency instead of a broadened one, as seen in the cases of θ≥[π/4]. The shedding frequency increases to a maximum of [fL/u∞]∼0.26 for the maximum slit size of ξ=0.5 mm. From the analysis of the x–t diagram and the modal analysis of vorticity and velocity magnitude in the wake, the peaks are indeed found to agree with the spectral analysis. More insights on the shedding vortices, momentum deficit in the wake, varying energy contents in the flow field, and the dominant spatiotemporal structures are also provided.

β-hydroxy-β-methylbutyrate-enriched nutritional supplements for obese adults during weight loss: study protocol of a randomised, double-blind, placebo-controlled clinical trial

IntroductionObesity is a public health challenge worldwide. To maintain a healthy weight, dieting and lifestyle changes are the first-line interventions; however, these interventions are of poor compliance and may cause...

Study on the technical parameters model of the functional components of cone crushers

Abstract A cone crusher is a machine that crushes rock materials with high efficiency and low power consumption; it is one of the typical road construction equipment. To improve the production efficiency, mechanical performance, and crushing performance of the cone crusher, thus increasing profit, this study used Discrete element method (DEM) particle analysis software to optimize the structure of the moving cone, studied the crushing effect of the crusher, and carried out kinetics analyses. Based on DEM, the structure of the cone crusher cavity was analyzed and optimized. A Y51 cone crusher was selected as a representative example to study its moving cone structure. By analyzing the factors that affect the performance and efficiency of the crusher, the precession angle, base angle, shape, and rotational speed of the moving cone were optimized. Using the Genetic Algorithm-Support Vector machine method (GA-SVW), the optimal combination of parameters was determined, and the key parts of the crusher were thus optimized.

Numerical investigation of gravity-driven particle flow along the trapezoidal corrugated plate for a moving packed bed heat exchanger

A heat transfer model based on the discrete element method was developed to investigate the effect of the trapezoidal corrugated plate on heat transfer. Particles flow along a trapezoidal corrugated plate unit (TCPU) were compared with that along a flat plate, and the appropriate base angles of the trapezoidal bulge were searched. In the upstream region of the trapezoidal bulge, the contact resistance of the TCPU decreases by 44% compared with that of the PLATE. In the side and downstream regions, the trapezoidal bulge enhances the mixing between particles, destroys the development of the temperature boundary layer and strengthens the heat transfer (average heat transfer rate increased by 14%). The heat transfer rate of adding the trapezoidal bulge is better than reducing the channel width at higher mass flow rates (> 1.07 g/s). When outlet velocity is 1 mm/s, base angles between 45°- 60° are beneficial for the heat transfer.