Study the Effect of Inductor and Pole Geometry on the Surface Roughness and Material Removal Weight Using Magnetic Abrasive Finishing Method

The traditional finishing method cannot keep up with recent labor market requirements, solve the problem of increasing production, improve the surface roughness and accuracy of workpiece. While the unconventional magnetic abrasive finishing (MAF) method has shown as a promising technique that can be used to finish complicated surfaces. MAF finishes metals, alloy, ceramic, and other materials that are difficult to finish by other processes. In another word, MAF improves the quality of surfaces with low cost. This paper focuses on optimize and study the effect of inductor and pole geometry (radius of hole, angle of core, angle of pole, radius of pole), on (surface roughness (Ra) and material removal weight (W)) and fined the optimum values that increase the efficiency of MAF method. Taguchi method employed to study the influence of geometry parameters and find the optimum values using orthogonal array L9. The results conclude that the most significant factor that effects change in surface roughness (ΔRa) and material removal weight(ΔW) are radius of the hole (R) and angle of core (α), respectively.

Excised host tissues weight: New Indicators of Total Knee Arthroplasty Worthy of Attention

Background: Knee osteoarthritis (KOA) is a crippling disease and affects many people around the world. Total knee arthroplasty (TKA) is an effective way to treat this disease. The objectaives of this study to compare the weight of the total knee arthroplasty implants and the weight of the natural knee in different groups and also to analyze facts which may affect the weight of surgical host excision. Methods: In total, 105 consecutive TKAs were enrolled in this prospective cohort study with three different brands of knee prostheses. Patients meeting the criterion were divided into the normal bone mass group, the osteopenia group or the osteoporosis group according to the results of preoperative bone density examination. The removal of bone and soft tissues that were collected during TKA operations of each group were weighed and compared with the total weight of the knee prosthesis (including implanted bone cement). Multivariate logistic stepwise regression analysis was conducted to identify indicators affecting host removal weight.Results: The average host removal weight was (132.56±36.88)g for normal bone mass group, (112.86±23.65)g for osteopenia group and (103.74±20.66)g for osteoporosis group. There were statically differences among the three groups. There was a significant difference between the normal bone mass group and the osteopenia group (P=0.003), while no difference between the osteopenia group and the osteoporosis group (P=0.154). No differences were found in the TKA components weight, bone cement weight and knee joint weight gained after TKA among all groups. Stepwise multiple regression analysis using the weight of excised host tissues as a dependent variable and BMD level, gender, age and other available indicators as independent variables revealed that BMD level(B=9.057, p=0.008), gender(B=21.692, p<0.001), Kellgren-Lawrence grade(B=13.790, p=0.003) are significant factors affecting excised host tissues weight. Conclusion: There is a positive correlation between the weight of the host removals of TKA and the patient's bone density. BMD level, gender and K-L stage of KOA were the main factors affecting the weight of the host removal.

Fishes and invertebrates of oil and gas platforms off California: an introduction and summary

This paper serves as an introduction to a symposium on the role that California oil and gas platforms serve as habitats for fishes and invertebrates. As of 2019, there are 27 platforms in state and federal waters off California, and the decommissioning of some of these platforms is imminent. Thus, consideration of whether to completely remove a platform or cut it off at some depth below the sea surface and retain the submerged portion as a reef is a decision that will occur in the near future. The objectives of the 10 papers in this dedicated issue of the Bulletin of Marine Science are to: (1) increase scientific understanding of the inter- and intrarelationships of fish and invertebrate populations at offshore oil and gas platforms and natural reefs within the Southern California Bight; (2) determine the extent of influence of platform assemblages on southern California and the Pacific coast populations of fishes and invertebrates; and (3) synthesize relevant reports, existing peer-reviewed literature, and new data analyses into a single peer-reviewed reference. This introductory paper contains a synopsis of all extant California platforms including information on: (1) the original operator, (2) the current operator of records, (3) the date the platform was installed, (4) the first production date, (5) the platform's distance from shore [including whether it is state or outer continental shelf (OCS) waters], (6) the bottom depth of the platform, (7) the number of well slots, (8) the number of conductors, (9) what the platform produces (oil and/or gas), (10) the platform jacket dimensions [generally at the seafloor (bottom)], (11) the platform's footprint, (12) the midwater surface area, (13) the total removal weight, (14) the platform location, (15) the shell mound size, (16) the shell mound volume, (17) the shell mound height, (18) the center of the shell mound location, and (19) the bottom slope. In addition, we present an overview of all previous research on the biology and ecology of California platform organisms.

Pengaruh Kemasan dan Susunan terhadap Sifat Fisik Buah Mangga Golek selama Transportasi

<p>Packaging has been designed for degrade of vibration and presser that to create broken and injury during transportation. The broken and injury fruit impact respiration process and to be continued. Mango fruit that injury impact respiration process. The aims of research was to study of physic characteristic of mango fruit “golek’’ to kind of packaging and setting in the packaging during transportation. The result of research was (1) There isn’t really impact to very really impact at the treatment of the fruit sstting to change colour, hardness and removal weight in packaging during transportation, (2) There isn’t really impact to very really impact at the treatment of kind of packaging to change colour and removal weight during transportation, (3) Packaging that been made from bamboo (basket) giving a the best of value was compared the others packaging to hardness of mango fruit during transportation.</p>

The Prediction of Material Removal and Surface Roughness of Workpiece during Abrasive Flow Machining

In order to study the finishing mechanism of abrasive flow machining (AFM), the model of material removal and solving method of surface roughness during material deformation have developed based on axial force and radial force. However, the axial force and radial force have been respectively measured by two pressure transducers fixed in the fixture. Both the material removal weight and surface roughness of workpiece have been calculated and measured during AFM experiments. The conclusions arrived by the analysis about the results of theoretical calculation are in agreement with the experimental AFM in some extent.

Electropolishing of Coronary Stents

Produce of coronary stents demands advanced precision. In the present study, electropolishing was performed on stainless steel slotted tube coronary stents made by laser cutting. The surface quality of stents has a significant influence on biocompatibility, therefore the optimal method for electropolishing were explored. Additionally, acid pickling as the pretreatment of electropolishing was also conducted. Pickling was necessary prior to electropolishing for decreasing roughness of the cutting zone and for removing the oxide films covering the stent surface. An optimal condition for electropolishing could also be established and it caused a smooth stent surface. Material removal (weight loss and strut width change) in the process of both pickling and electropolishing was investigated. Furthermore, material characterization of the stents was determined by means of composition analysis, metallographic characterization and microstructural analysis.