Thematische Bibliographien / Molding segment

Inhaltsverzeichnis

Zeitschriftenartikel
Dissertationen
Buchteile
Konferenzberichte

Auswahl der wissenschaftlichen Literatur zum Thema „Molding segment“

Autor: Grafiati

Veröffentlicht am 28. Juni 2021

Zuletzt aktualisiert am 3. Februar 2022

Geben Sie eine Quelle nach APA, MLA, Chicago, Harvard und anderen Zitierweisen an

Wählen Sie eine Art der Quelle aus:

Machen Sie sich mit den Listen der aktuellen Artikel, Bücher, Dissertationen, Berichten und anderer wissenschaftlichen Quellen zum Thema "Molding segment" bekannt.

Neben jedem Werk im Literaturverzeichnis ist die Option "Zur Bibliographie hinzufügen" verfügbar. Nutzen Sie sie, wird Ihre bibliographische Angabe des gewählten Werkes nach der nötigen Zitierweise (APA, MLA, Harvard, Chicago, Vancouver usw.) automatisch gestaltet.

Sie können auch den vollen Text der wissenschaftlichen Publikation im PDF-Format herunterladen und eine Online-Annotation der Arbeit lesen, wenn die relevanten Parameter in den Metadaten verfügbar sind.

Zeitschriftenartikel zum Thema "Molding segment"

Vijaykumar, V., Lidhiya Alexander und Pazhaniswamy Manivannan. „A Review on Nasoalveolar Molding“. Journal of Scientific Dentistry 10, Nr. 2 (2020): 49–50. http://dx.doi.org/10.5005/jp-journals-10083-0922.

Der volle Inhalt der Quelle

Annotation:

ABSTRACT A common hereditary defect of the oral cavity with grave socioeconomic problem is cleft lip and palate. Although the defect varies in forms and severity, the individuals presented with glitches regarding functions and esthetics. Authors claim that nasoalveolar molding improves facial esthetics and function and has gained more attention. The objective of presurgical nasoalveolar molding comprises improving lip segment, inferior lateral alar cartilages, and alveolar cleft segments. Outcomes of presurgical nasoalveolar molding are promising and hence are encouraged immediately after birth and continued until further corrective surgery is planned. The rationale of presurgical nasoalveolar molding is approximation of the alveolar segments, wherein the surgeon has to perform gingivoperiosteoplasty followed by corrective lip surgery. How to cite this article: Manivannan P, Alexander L, Vijaykumar V. A Review on Nasoalveolar Molding. J Sci Dent 2020;10(2):49–50.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Hu, Hai Ming, De Bao Yin und Hui Li. „Forming Process of Segment-Narrow-Bars on the PCR Mold“. Key Engineering Materials 561 (Juli 2013): 270–73. http://dx.doi.org/10.4028/www.scientific.net/kem.561.270.

Der volle Inhalt der Quelle

Annotation:

The narrow bars on tire mold segment are used for molding the sipes on the tread, Its size is small.Its shape and location is diverse and process is complex. This article, through processing feasibility analysis of the narrow bars, combined with production practice, conducted a systematic and detailed explanations on the process of molding the narrow bars in the precision casting method for molding segment.Through analyse a number of empirical conclusions about narrow bars’ forming process which have drawn, and has proved the practicality of these methods through practice.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Saad, M. S., M. Fata, A. Farouk, A. M. A. Habib, M. Gad, M. B. Tayel und M. K. Marei. „Early Progressive Maxillary Changes with Nasoalveolar Molding: Randomized Controlled Clinical Trial“. JDR Clinical & Translational Research 5, Nr. 4 (20.12.2019): 319–31. http://dx.doi.org/10.1177/2380084419887336.

Der volle Inhalt der Quelle

Annotation:

Objectives: Quantitative assessment of 3-dimensional progressive changes of the maxillary geometry in unilateral cleft lip palate (UCLP) with and without nasoalveolar molding (NAM). Methods: The study was designed as a prospective 2-arm randomized controlled clinical trial conducted in parallel. Forty infants with nonsyndromic UCLP were randomly assigned into a NAM-treated group (n = 20) and non–NAM treated group (n = 20). A total of 120 laser-scanned maxillary casts were collected and blindly analyzed via a modified algorithm at T0 (initial visit; baseline), T1 (after 3 wk; first interval), and T2 (after 6 wk; second interval). The main outcome measures were the amount and rate of cleft gap changes, the midline position, and the transverse, sagittal, and vertical growth through intervals. Results: More than 50% of the cleft gap (56.42%; P < 0.001) was reduced in the first 3 wk of alveolar molding (AM). The end point of the AM was obtained in 6 wk (86.25%; P < 0.001); then, the kinks of the greater segment were noticed. The AM effect decreased as far as posterior; the anterior arch width reduced slightly (1.23%; P < 0.001), while the middle and posterior arches increased slightly (P > 0.999 and P = 0.288, respectively). The posterior arch width was the least changing and was considered a baseline, while the anterior was the pivot of the segment rotation. Both groups showed different patterns of segment rotation and sagittal growth. The non–NAM treated group showed a slight increase in cleft gap length, arch width, and midline position. Conclusion: Based on this study, it was concluded that the NAM treatment is effective in minimizing cleft severity and realigning maxillary segments without the deterioration of the transverse and vertical arch growth. Near follow-up visits are recommended to monitor the rapid gap reduction within the first 3 wk. Further trials are recommended to compare the outcomes regarding the sagittal growth to reference values ( ClinicalTrials.gov NCT03029195). Knowledge Transfer Statement: The results of this study will help clinicians understand nasoalveolar molding biomechanics that may improve the treatment outcomes for patients with unilateral cleft lip and palate. The trial data can be a valuable guide to the qualitative and quantitative predictive virtual molding in computer aided design–simulated nasoalveolar molding therapy. The modified algorithm can be used by researchers to quantify the rate, the sequence, and the direction of the maxillary segments movement in unilateral cleft lip and palate.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Chang, Chih-Yuan, und Wei-Ru Chen. „Influence of processing variables on quality of unsaturated polyester/E-glass fiber composites manufactured by double-bag progressive compression method“. Advances in Mechanical Engineering 10, Nr. 9 (September 2018): 168781401879853. http://dx.doi.org/10.1177/1687814018798531.

Der volle Inhalt der Quelle

Annotation:

A hybrid process of articulated resin transfer molding and vacuum-assisted resin infusion, called double-bag progressive compression method, has been invented to fabricate composite parts. In double-bag progressive compression method, the secondary bag is divided into several segments. During resin infusion, the double bag is drawn upward by vacuum, and the initial flow resistance offered by the loose preform is low. Once the resin infusion is completed, the vacuum on the segmented bags is progressively released to ambient pressure, and the segmental compression is sequentially performed until unnecessary resin is completely removed. This research is to experimentally investigate the influence of double-bag progressive compression method processing parameters, including vacuum pressure in the cavity, number of segments, initiating time of the next compression, temperature of the heated air, initiating segment of the heated air, initial height of the mold cavity, and excess infused resin, on the mechanical property of the part. The design of experiments adopts Taguchi’s method. Results show that the double-bag progressive compression method significantly reduces total filling time and maximally increases the flexural modulus of the part by 17.81% as compared with the typical vacuum-assisted resin infusion. A preferable parameter condition is proposed by taking both the flexural modulus and the operation complexity into account.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Cooper, Stuart L., und John A. Miller. „Chain Conformation in Elastomeric Multiblock Copolymers as Measured by Small-Angle Neutron Scattering“. Rubber Chemistry and Technology 58, Nr. 5 (01.11.1985): 899–912. http://dx.doi.org/10.5254/1.3536102.

Der volle Inhalt der Quelle

Annotation:

Abstract Small-angle neutron scattering has been shown to be an effective technique for investigating segment conformation in two-phase multiblock copolymer systems. By choosing the appropriate isotopic compositions, either segment can be investigated, as can the whole chain. The best approach to the experiment is to use a phase-contrast matched sample, one where no interphase scattering occurs. This allows the experiments to be carried out on a single sample, simplifying the experiment, and reducing the beam time requirements. Equations (2) and (3) describe the phase-contrast matched criterion. At room temperature, the polyether soft segments in the polyurethane elastomer-and in the polyether-polyester block copolymers are somewhat extended on the average relative to the bulk oligomer conformation. In the polyether-polyester with a lower hard-segment content, the soft segments are less extended than in the higher ester content material. A distribution of conformations occurs in these materials, with a majority of the soft segments being nearly in a random-coil conformation. A substantial number of segments are fairly taut, leading to an average conformation that is somewhat extended relative to the random coil conformation. The soft-segment radius of gyration in the polyurethane material initially decreases with increasing temperature. As the temperature rises, the retractive force on the taut soft segments increases, thus facilitating the extraction of hard segments from the amorphous hard phase into the soft phase. One would expect that the degree of phase separation would decrease with increasing temperature due to such a mechanism, and in fact this is borne out by small-angle x-ray scattering studies. Above 150°C, an upturn in the soft-segment radius of gyration is observed. Koberstein et al. propose a phase mixing transition around this temperature in polyurethane systems. Such a transition implies a greater compatibility between the hard and soft segment types at elevated temperatures. Thus, a swelling of the soft segments is seen due to favorable interactions with the hard segments located in the soft phase. A schematic diagram of the polyurethane microstructure and chain conformation is presented in Figure 9. The soft-segment radius of gyration in the polyether-polyester materials decreases smoothly with increasing temperature. This is primarily due to a decrease in the number of taut tie molecules present at elevated temperatures due to the rearrangement of the hard crystalline domains. In addition, relaxation of stresses introduced by molding these samples below the hard-segment crystalline melting temperature may contribute to the decrease in the soft-segment Rg.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Spengler, Adam L., Carmen Chavarria, John F. Teichgraeber, Jaime Gateno und James J. Xia. „Presurgical Nasoalveolar Molding Therapy for the Treatment of Bilateral Cleft Lip and Palate: A Preliminary Study“. Cleft Palate-Craniofacial Journal 43, Nr. 3 (Mai 2006): 321–28. http://dx.doi.org/10.1597/05-093.1.

Der volle Inhalt der Quelle

Annotation:

Objective To evaluate the outcome of presurgical nasoalveolar molding therapy in the treatment of patients with bilateral cleft lip and palate. Design A prospective study with blinded measurements. Setting The Cleft and Craniofacial Clinic at the University of Texas at Houston Medical School, Houston, Texas. Patients Eight patients with bilateral cleft lip and palate, treated between 2002 and 2004. Interventions The starting age for presurgical nasoalveolar molding therapy was 34.9 days and the average length of the therapy was 212.5 days. Main Outcome Measures Measurements of intraoral and extraoral casts were performed, and statistical analyses were used to compare the differences between measurements before and after therapy. Results Intraoral measurements demonstrated that there was a statistically significant reduction of the premaxillary protrusion and deviation. There was also a significant reduction in the width of the larger cleft. Extraoral measurements revealed that there was a significant increase in the bi-alar width and in the columellar length and width. Moreover, there was a significant improvement in columellar deviation. Finally, the nostril heights of both sides were increased. Conclusion The authors have quantitatively shown that presurgical nasoalveolar molding therapy has significant advantages in the treatment of bilateral cleft lip and palate patients. It improves the nasal asymmetry and deficient nasal tip projection associated with bilateral cleft lip and palate. It also forces the protruded premaxillary segment into alignment with the dental alveolar segments, improving the shape of the maxillary arch. As a result, the changes associated with presurgical nasoalveolar molding therapy help decrease the complexity of subsequent surgeries.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Birkar, Smita, Joey Mead und Carol Barry. „INJECTION MOLDING OF THERMOPLASTIC ELASTOMERS FOR MICROSTRUCTURED SUBSTRATES“. Rubber Chemistry and Technology 87, Nr. 4 (01.12.2014): 629–46. http://dx.doi.org/10.5254/rct.14.86924.

Der volle Inhalt der Quelle

Annotation:

ABSTRACT Microstructured surfaces injection molded from thermoplastic elastomers have emerging applications as superhydrobic surfaces and patterned adhesives, but there is a limited understanding of the factors affecting replication with these materials. This work investigates the interactions of the tooling aspect ratio and feature orientation (negative and positive tooling) and thermoplastic elastomer hard segment content on microfeature replication. Electroformed nickel tooling having positive and negative features with different geometries and aspect ratios of 0.02:1 to 2:1 were molded from three copolyester thermoplastic elastomers with similar chemistry and different hardness values. The tooling and part features were characterized for feature depth and height as well as feature definition using scanning electron microscopy and optical profilometry. Results were correlated with elastomer properties.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Suri, Sunjay, und Bryan D. Tompson. „A Modified Muscle-Activated Maxillary Orthopedic Appliance for Presurgical Nasoalveolar Molding in Infants with Unilateral Cleft Lip and Palate“. Cleft Palate-Craniofacial Journal 41, Nr. 3 (Mai 2004): 225–29. http://dx.doi.org/10.1597/02-141.1.

Der volle Inhalt der Quelle

Annotation:

Objective The purpose of this article is to describe a modified appliance and treatment approach for presurgical nasoalveolar molding in infants with unilateral cleft lip and palate. Methods This approach uses a plate held in with outriggers, which prevents the cleft-widening effect of the tongue, helps with tongue tip placement, and utilizes the functional movements of the facial musculature to guide and relocate the major segment medially to its normal position. Nasal molding is undertaken after most of the lateromedial correction of the alveolar position. Conclusions This technique helps to improve alveolar position, nasal septum alignment, nasal symmetry, and nasal tip projection prior to lip repair.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Vura, Nandagopal, Rajasekhar Gaddipati, Yudhistar Palla und Pranay Kumar. „An Intraoral Appliance to Retract the Protrusive Premaxilla in Bilateral Cleft Lip Patients Presenting Late for Primary Lip Repair“. Cleft Palate-Craniofacial Journal 55, Nr. 4 (23.01.2018): 622–25. http://dx.doi.org/10.1177/1055665617732783.

Der volle Inhalt der Quelle

Annotation:

The protruding and deviated premaxilla in bilateral complete cleft lip and palate (BCL/P) patients causes a perplexing problem in achieving a tension-free primary lip closure. An innovative noninvasive active intraoral Fixed Pre-Surgical Cleft Orthopedic (FPSCO) appliance is presented that has enabled to successfully reposition the premaxillary segment to a more favorable position prior to the surgical repair in 4 BCL/P patients, who reported late for treatment with a mean age of 18 ± 3 months. All the patients had at least 1 deciduous tooth erupted in 3 cleft segments, 1 premaxilla (PM), and 2 lateral maxillary (LM) segments. This innovative approach is a noninvasive method of getting the cleft segments closer prior to chelioplasty, where conventional presurgical nasoalveolar molding (PNAM) is not possible, which needs to be done early in life as it requires circulating maternal estrogen levels to achieve results preferably possible in patients younger than 3 to 6 months. Bonding to erupted teeth with glass ionomer cement was implemented to secure the appliance. Nickel-titanium (Ni-Ti) closed-coil springs were used that delivered continuous forces of 150 g/5 oz per side to retract the premaxillary segment. The mean active period of treatment time was 3.5 ± 1.6 months and the retention period was 1.2 ± 0.6 months, following which cheiloplasty was performed.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Bauer, Franz Xaver, Markus Schönberger, Johannes Gattinger, Markus Eblenkamp, Erich Wintermantel, Andrea Rau, Florian Dieter Güll, Klaus-Dietrich Wolff und Denys J. Loeffelbein. „RapidNAM: generative manufacturing approach of nasoalveolar molding devices for presurgical cleft lip and palate treatment“. Biomedical Engineering / Biomedizinische Technik 62, Nr. 4 (28.08.2017): 407–14. http://dx.doi.org/10.1515/bmt-2016-0035.

Der volle Inhalt der Quelle

Annotation:

AbstractNasoalveolar molding (NAM) is an accepted treatment strategy in presurgical cleft therapy. The major drawbacks of the treatment listed in the literature relate to the time of the treatment and the coordination of the required interdisciplinary team of therapists, parents, and patients. To overcome these limitations, we present the automated RapidNAM concept that facilitates the design and manufacturing process of NAM devices, and that allows the virtual modification and subsequent manufacture of the devices in advance, with a growth prediction factor adapted to the patient’s natural growth. The RapidNAM concept involves (i) the prediction of three trajectories that envelope the fragmented alveolar segments with the goal to mimic a harmonic arch, (ii) the extrusion from the larger toward the smaller alveolar segment along the envelope curves toward the harmonic upper alveolar arch, and (iii) the generation of the NAM device with a ventilation hole, fixation pin, and fixation points for the nasal stents. A feasibility study for a vector-based approach was successfully conducted for unilateral and bilateral cleft lip and palate (CLP) patients. A comparison of the modified target models with the reference target models showed similar results. For further improvement, the number of landmarks used to modify the models was increased by a curve-based approach.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Mehr Quellen

Dissertationen zum Thema "Molding segment"

Měchura, Lukáš. „Vývoj procesních parametrů technologie Selective Laser Melting pro výrobu lisovací formy pneumatik“. Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-444403.

Der volle Inhalt der Quelle

Annotation:

The diploma thesis deals with finding suitable process parameters for the production of molding segment by SLM technology. It consists of a combination of structures, shells, thin slats and bulk parts. The tested material is maraging steel 300. The research part deals with the problem of choice of suitable process parameters, such as laser power and speed, hatch distance and thickness of the built layer. The achievable mechanical properties of the parts and the choice of the suitable structure were also examined. In the thesis were found suitable process parameters for printing of bulk parts and structures.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Buchteile zum Thema "Molding segment"

Lovisolo, Carlo. „Chapter-71 Corneal Collagen Crosslinking with Riboflavin (C3R) Combined with Intrastromal Ring Segment Implantation and Overnight Contact Lens Molding in Keratoconus“. In Surgical Techniques in Ophthalmology Refractive Surgery, 434–44. Jaypee Brothers Medical Publishers (P) Ltd., 2010. http://dx.doi.org/10.5005/jp/books/10885_71.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Calossi, Antonio, und Carlo Lovisolo. „Corneal Collagen Cross-linking with Riboflavin (C3-R) Combined with Intrastromal Ring Segment Implantation and Overnight Contact Lens Molding in Keratoconus“. In Surgical Techniques in Ophthalmology: Corneal Surgery, 304. Jaypee Brothers Medical Publishers (P) Ltd., 2010. http://dx.doi.org/10.5005/jp/books/11369_51.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Calossi, Antonio, und Carlo Lovisolo. „Corneal Collagen Cross-linking with Riboflavin (C3-R) Combined with Intrastromal Ring Segment Implantation and Overnight Contact Lens Molding in Keratoconus“. In Mastering Corneal Collagen Cross-linking Techniques, 98. Jaypee Brothers Medical Publishers (P) Ltd., 2009. http://dx.doi.org/10.5005/jp/books/10491_17.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Konferenzberichte zum Thema "Molding segment"

Yueh, Yuh-Shan, und R. Allen Miller. „A Systematic Approach to Support Design for Manufacturability in Injection Molding and Die Casting“. In ASME 1995 15th International Computers in Engineering Conference and the ASME 1995 9th Annual Engineering Database Symposium collocated with the ASME 1995 Design Engineering Technical Conferences. American Society of Mechanical Engineers, 1995. http://dx.doi.org/10.1115/cie1995-0804.

Der volle Inhalt der Quelle

Annotation:

Abstract In designing a part to be produced by injection molding or die casting, designers need to consider manufacturing characteristics of the part such as filling and ejectability from the dies as well as functional issues. The typical design cycle is iterative, laborious and time-consuming. In this paper, we present a procedure for defining parting information (locations where the mold/die come together), and recognizing the links between part design and die/mold construction. Many decisions and design details, such as draft on surfaces parallel to the draw (die opening) direction, gate and runner locations, vent locations, etc., depend on the parting locations and characteristics. Parting information is normally not part of the geometric model of the part design. Parting design, including draw direction and parting location, is addressed through a custom user interface which contains several options related to different levels of geometric modeling data. The resulting specification is stored in a segment structure which provides a flexible parting description and fits within the B-rep hierarchy. The reasoning about the linking of related surfaces is accomplished by splitting and traversing the extracted geometric entities based on parting definition. The entities covered by the same die/mold component are aggregated as a face group which is a set of complete or partial surfaces with the parting definition as the boundary information and with the draw direction as the moving information. In this approach, manufacturing information can be strongly coupled with geometric data to form a complete part model which supports manufacturability assessment and facilitates any necessary shape transformations to achieve a manufacturable part in a straightforward manner so that design iterations can be controlled and development cost can be reduced.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Feng, Zhengkun, Henri Champliaud und Thien-My Dao. „Three-Dimensional Finite Element Analyses for Pyramidal Three-Roll Bending Process“. In ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-10888.

Der volle Inhalt der Quelle

Annotation:

Many applications of conical roll bending can be found in manufacturing industry, such as rolling a conical segment of a wind turbine tower or an alternative process of molding a large crown for a Francis turbine. This molding process could be achieved by assembling several conical segments. For the purpose of using cylindrical rolls or reusing the existing conical rolls of the kinematical conical roll bending process for non-kinematical conical roll bending process, attachments were proposed in order to reduce the velocity at the top edge of the plate. In contrast with a kinematical conical roll bending machine where no sliding exists between the plate and the rolls, the contact surface near the top edge of the plate of the three driving rolls of a non-kinematical conical roll bending machine slides on the plate due to the friction between the attachments and the plate. Therefore, the appropriate velocity at the top edge of the plate corresponding to that of the kinematical conical roll bending process can be obtained. This paper deals with the simulation analyses of the non-kinematical multi-pass conical roll bending process based on the finite element method, for example, the analyses of the applied force on the pressing roll. The components of the roll bending machine, such as the rolls and the attachments, etc. were assumed to be rigid bodies and the 4-node shell elements were used in the modeling. Bilinear material properties were used for the elasto-plasticity of the plate. Automatic node-surface contacts were chosen on the interfaces between the plate and the rigid bodies. The nonlinear equations which represent the structural dynamics with large displacement were resolved using explicit time integration. The simulations were performed under the well-known ANSYS/LS-DYNA environment. A well bent cone was obtained and compared very well with the ideal cone. The numerical simulation results show that the bent cone depends on the static and dynamic friction coefficients for a geometrical configuration with an appropriate span of the outer rolls.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Zhu, Kejun, und Xiaolong Zhu. „Study on Molding Rate with Segmented Control in Glass Molding Process“. In 2019 2nd World Conference on Mechanical Engineering and Intelligent Manufacturing (WCMEIM). IEEE, 2019. http://dx.doi.org/10.1109/wcmeim48965.2019.00122.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Ghosh, Kalyanjit, und Srinivas Garimella. „Dynamic Modeling of Thermal Processes in Rotational Molding“. In ASME 2004 Heat Transfer/Fluids Engineering Summer Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/ht-fed2004-56801.

Der volle Inhalt der Quelle

Annotation:

Transient heat transfer phenomena in the rotational molding of plastic parts are modeled in this study. Natural convection and radiation from the furnace and flue gases to the mold housing are analyzed. Other models include transient heat transfer through the mold, single-phase conduction through the particulate plastic material prior to phase change, melting of the plastic, and heating of the liquid pool. Subsequent staged cooling and solidification of the mold and plastic using a combination of free and forced convection and radiation is also modeled. Information about the properties of the plastic in powder, liquid and solid forms is obtained from the literature. Assumptions about the behavior of the plastic powder and the molten plastic during the rotational operations are also made in accordance with the available literature. The mold wall, melt and solidified plastic regions are divided into a number of finite segments to track the temperature variation with time during the molding process. The corresponding variations in masses and thicknesses of the melt and solidified plastic regions are also estimated. Consequently, the energy consumption rates in the process are estimated. The model is applied to a specific molding process in a commercial rotational molding plant. Parametric studies of the effect of heating and cooling durations on the plastic temperatures and the energy consumption rates are also conducted. These analyses provide insights about opportunities for optimization of the heating and cooling schedules to reduce overall energy consumption and also improve throughput.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Xu, Di, Zhen-tao Guo, Shu-feng Li, Jin-mei Zheng, Tie-jun Li, Long Zhang, Xin-peng Hou, Wei Tang, Yan Chen und Jia Zhang. „The Research of Shielding Material for Mixed Field“. In 2013 21st International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/icone21-16188.

Der volle Inhalt der Quelle

Annotation:

This paper developed a kind of highly-filled and ultra-thickness shielding materials; its performance meets shielded neutron-gamma mixed field requirements. Through EDS, theoretical calculation, formulation design, sample preparation and performance test, we carry out the research of base material, neutron absorber, γ-ray absorbent, functional additives and products molding process. The experimental results show that: selection of polyolefin with high hydrogen content as base material, with 15∼25% B4C as a neutron absorber, with 60%∼70% lead powder as a γ-ray absorbent, aiming at the development of protection requirements can make the shielding performance of products reach the ideal level. At the same time, according to the characteristics of system of inorganic filler, the high product thickness, by applying the method of stepped cooling and segmented pressurizing, especially the effective control of crystal formation process to ensure that the product molding and use, overall performance, shielding performance, at the same time improve the yield of the product.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Nannapaneni, Saideep, und Sankaran Mahadevan. „Manufacturing Process Evaluation Under Uncertainty: A Hierarchical Bayesian Network Approach“. In ASME 2016 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/detc2016-59226.

Der volle Inhalt der Quelle

Annotation:

This paper proposes a Hierarchical Bayesian Network (HBN) approach to estimate the uncertainty in performance prediction of manufacturing processes by aggregating the uncertainty arising from multiple models at multiple levels. A HBN is an extension of a Bayesian network (BN) for modeling hierarchical or multi-level systems where each node may represent a lower-level BN. The BNs at different levels can be constructed either using physics-based models or available data or by a hybrid approach through a combination of physics-based models and data. An improved BN learning algorithm is presented where the topology is learnt using an existing algorithm but different parametric and non-parametric models are fit to represent the conditional probabilities. Data for model calibration may be available at multiple levels such as at the unit process level or line level or sometimes at the factory level. Using all the data for calibration can be computationally expensive; therefore, a multi-level segmented approach for model calibration is developed. The injection molding process is used to demonstrate the proposed methodologies for uncertainty prediction in its energy consumption.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Anderson, Jacob P., und M. Cengiz Altan. „Properties of Composite Cylinders Fabricated by Bladder Assisted Composite Manufacturing (BACM)“. In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-65285.

Der volle Inhalt der Quelle

Annotation:

An innovative manufacturing method, BACM (Bladder Assisted Composite Manufacturing), to fabricate geometrically complex, hollow parts made of polymeric composite materials is presented. BACM uses an internally heated bladder to provide the consolidation pressure at the required cure temperature, and thus produces high quality components. The feasibility of this manufacturing method is demonstrated by fabricating laminated composite cylinders using multiple cure pressures and wall thicknesses. The mechanical properties, energy consumed during the curing, and void content of the composite cylinders, are investigated in detail. The curing of composite cylinders was carried out by circulating heated air inside the bladder. Using the described heating method a number of 2-, 4-, and 6-ply composite cylinders made of E-glass/epoxy prepreg (Newport 321/7781) were prepared as test samples. Cylinders were cured at 121°C (250°F) for 2 hours using bladder pressures of 207 kPa (30 psi), 345 kPa (50 psi), 483 kPa (70 psi), and 621 kPa (90 psi). The mechanical behavior of the cylinders were characterized by compressing sample rings and loading ring segments in three-point bending. The fiber volume fraction and the void content of the cylinders were determined from resin burn-off experiments and density measurements. The cylinders produced using the BACM process were found to exhibit excellent surface quality. The elastic moduli, failure strength, and void contents of the cylinders were comparable to the values obtained from flat laminates produced by hot plate molding. Compared to conventional bladder manufacturing methods, the BACM process reduced the energy required to cure the cylinder by more than 50%.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Vick, Michael, Trent Young, Matthew Kelly, Steven Tuttle und Katherine Hinnant. „A Simple Recuperated Ceramic Microturbine: Design Concept, Cycle Analysis, and Recuperator Component Prototype Tests“. In ASME Turbo Expo 2016: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/gt2016-57780.

Der volle Inhalt der Quelle

Annotation:

Ceramic recuperators could enable microturbines to achieve higher fuel efficiency and specific power. Challenges include finding a suitable ceramic fabrication process, minimizing stray heat transfer and gas leakage, mitigating thermal stress, and joining the ceramic parts to neighboring metal components. This paper describes engine and recuperator design concepts intended to address these obstacles. The engine is sized to produce twelve kilowatts of shaft power, and it has a reverse-flow compressor and turbine. Motivations for this layout are to balance axial thrust forces on the rotor assembly; to minimize gas leakage along the rotating shaft; to reduce heat transfer to the compressor diffuser; to enable the use of a simple, single-can combustor; and to provide room for lightweight ceramic insulation surrounding all hot section components. The recuperator is an annular, radial counterflow heat exchanger with the can combustor at the center. It is assembled from segmented wafers made by ceramic injection molding (CIM). These are housed in a pressure vessel to load the walls mainly in compression, and are joined together by flexible adhesives in the cool areas to accommodate thermal expansion. A representative wafer stack was built by laser-cutting, laminating, and sintering tapecast ceramic material. The prototype was tested at temperatures up to 675°C, and the results were used to validate analytical and computational fluid dynamics (CFD) models, which were then used to estimate the effectiveness of the actual design. Turbomachinery efficiencies were also calculated using CFD, and allowances were made for additional losses like bearing friction and gas leakage. Based on these component performance estimates, a cycle model indicates the engine could achieve a net fuel-to-electrical efficiency of 21%, at a core weight including the recuperator of 11 kg, or about 1 kg/kW electric output.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Wir bieten Rabatte auf alle Premium-Pläne für Autoren, deren Werke in thematische Literatursammlungen aufgenommen wurden. Kontaktieren Sie uns, um einen einzigartigen Promo-Code zu erhalten!