A ball joint for an automobile steering system is a pivot component which is connected to knuckle and lower control arm. The manufacturing process for its caulking comprises spinning and deforming. ...In this study, the process was simulated by flexible multibody dynamics. The caulking was evaluated qualitatively through numerical analysis and inspecting a plastically deformed shape. The structural responses of a ball joint, namely, pull-out strength and stiffness, are commonly investigated in the development process. Thus, following the caulking analysis, the structural responses were considered. In addition, three design variables related to the manufacturing process were defined, and the effects of design variables with respect to pull-out strength, caulking depth, and maximum stress were obtained by introducing the DOE using an L9 orthogonal array. Finally, the optimum design maximizing the pull-out strength was suggested. For the final design, the caulking quality and the pull-out strength were investigated by making six samples and their tests.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
A Separator is a device installed in industrial applications to separate mixed objects. The separator of interest in this research is a cyclone type, which is used to separate a steam-brine mixture ...in a geothermal plant. The most important performance of the cyclone separator is the collection efficiency. The collection efficiency in this study is predicted by performing the CFD (Computational Fluid Dynamics) analysis. This research defines six shape design variables to maximize the collection efficiency. Thus, the collection efficiency is set up as the objective function in optimization process. Since the CFD analysis requires a lot of calculation time, it is impossible to obtain the optimal solution by linking the gradient-based optimization algorithm. Thus, two approximation methods are introduced to obtain an optimum design. In this process, an L18 orthogonal array is adopted as a DOE method, and kriging interpolation method is adopted to generate the metamodel for the collection efficiency. Based on the 18 analysis results, the relative importance of each variable to the collection efficiency is obtained through the ANOVA (analysis of variance). The final design is suggested considering the results obtained from two optimization methods. The fluid flow analysis of the cyclone separator is conducted by using the commercial CFD software, ANSYS-CFX.
In this paper, the simplified approach using commercial computer software code was adopted to predict the performance of a kettle typed shell and tube heat exchanger. Similarly the numerical analysis ...using ANSYS/CFX is conducted for the same design and the result data are collected to analyze its performance numerically. In general, the heat exchanger performances are evaluated by predicting the temperature difference and pressure drop. The result data of both the analysis are compared to find the differences between the data. From the comparison, we came to know that the error percentage between the two analysis results is very low which is acceptable proving our design is convincible. Thereby we fabricated a prototype model of shell and tube heat exchanger (kettle type) with the same parameters used for these analyses.
A plastic ELISA-on-a-chip (EOC) employing the concept of cross-flow immuno-chromatographic analysis was applied to the measurement of botulinum neurotoxin A (BoNT/A) as agent for bio-terrorism. Two ...monoclonal antibodies specific to the heavy chain of the toxin were raised and identified to form sandwich binding complexes as the pair with the analyte. For the construction of an immuno-strip, one was utilized as the capture antibody immobilized onto nitrocellulose membrane and the other as the detection coupled to an enzyme, horseradish peroxidase. The two plates of EOC used in this study were fabricated by injection molding of polycarbonate to improve the reproducibility of manufacture and, after inclusion of the immuno-strip, bonded using a UV-sensitive adhesive. Under optimal conditions of analysis, the chip produced a color signal in proportion to the analyte dose and the signal was quantified using a detector equipped with a digital camera. From the dose–response curve, the detection limit of BoNT/A was 2.0
ng
mL
−1, approximately five times more sensitive than a commercial-version detection kit employing colloidal gold tracer.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
AIM: To predict the rate of lymph node(LN) metastasis in diffuse- and mixed-type early gastric cancers(EGC) for guidelines of the treatment.METHODS: We reviewed 550 cases of EGC withdiffuse- and ...mixed-type histology. We investigated the clinicopathological factors and histopathological components that influence the probability of LN metastasis, including sex, age, site, gross type, presence of ulceration, tumour size, depth of invasion, perineural invasion, lymphovascular invasion, and LN metastasis status. We reviewed all slides and estimated the proportions of each tumour component; pure diffuse type, mixed-predominantly diffuse type(diffuse > intestinal type), mixed-predominantly intestinal type(intestinal > diffuse type), and mixed diffuse = intestinal type. We calculated the extents of the respective components.RESULTS: LN metastasis was observed in 12.9%(71/550) of early gastric cancers cases 15/288 mucosal EGCs(5.2%) and 56/262 submucosal EGCs(21.4%). Of 550 cases, 302 were diffuse-type and 248 were mixed-type EGCs. Of 248 mixed-type EGCs, 163 were mixed-predominantly diffuse type, 82 were mixed-predominantly intestinal type, and 3 were mixed diffuse = intestinal type. Mixed-type cases with predominantly diffuse type histology showed a higher frequency of LN metastasis(20.2%) than cases of pure diffuse type(9.3%) and predominantly intestinal type(12.2%) histology. We measured the dimensions of each component(intestinal and diffuse type) to determine the association of the extent of each component with LN metastasis in mixed-type gastric carcinoma. The total tumour size and the extent of poorly differentiated components was associated with LN metastasis, while that of signet ring cell components was not.CONCLUSION: We recommend careful identification and quantitative evaluation of mixed-type early gastric cancer components after endoscopic resection to determine the intensity of the treatment.
This paper is focused on a global stiffness method for cross-ply laminated composite plates with distributed delaminations and matrix cracks that makes it possible to find its solution by simply ...replacing stiffness quantities in the known solution for the undamaged counterpart.
Local and zero stiffness model are introduced to determine the local stiffness in damaged regions and using the energy functional expression based on the first-order shear deformation theory (FSDT) and the classic laminate theory (CLT), the global stiffness is analytically determined by combining stiffness terms in undamaged and damaged regions with corresponding area ratio weights.
The obtained global stiffness is used to analyse bending and buckling problem of a simply supported plate with distributed delaminations and matrix cracks subjected to in-plane and transverse loads, being validated through ANSYS simulation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This study identified factors predicting malignant upgrade for atypical ductal hyperplasia (ADH) diagnosed on core-needle biopsy (CNB) and developed a nomogram to facilitate evidence-based decision ...making.
This retrospective analysis included women diagnosed with ADH at the National Cancer Centre Singapore (NCCS) in 2010-2015. Cox proportional hazards regression was used to identify clinical, radiological, and histological factors associated with malignant upgrade. A nomogram was constructed using variables with the strongest associations in multivariate analysis. Multivariable logistic regression coefficients were used to estimate the predicted probability of upgrade for each factor combination.
Between 2010 and 2015, 238,122 women underwent mammographic screening under the National Breast Cancer Screening Program. Among 29,564 women recalled, 5,971 CNBs were performed. Of these, 2,876 underwent CNBs at NCCS, with 88 patients (90 lesions) diagnosed with ADH and 26 lesions upgraded to breast malignancy on excision biopsy. In univariate analysis, factors associated with malignant upgrade were the presence of a mass on ultrasound (
0.018) or mammography (
0.026), microcalcifications (
0.047), diffuse microcalcification distribution (
0.034), mammographic parenchymal density (
0.008). and ≥ 3 separate ADH foci found on biopsy (
0.024). Mammographic parenchymal density (hazard ratio HR, 0.04; 95% confidence interval CI, 0.005-0.35;
0.014), presence of a mass on ultrasound (HR, 10.50; 95% CI, 9.21-25.2;
0.010), and number of ADH foci (HR, 1.877; 95% CI, 1.831-1.920;
0.002) remained significant in multivariate analysis and were included in the nomogram.
Our model provided good discrimination of breast cancer risk prediction (C-statistic of 0.81; 95% CI, 0.74-0.88) and selected for a subset of women at low risk (2.1%) of malignant upgrade, who may avoid surgical excision following a CNB diagnosis of ADH.
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