• Journal of Korean Institute of Industrial Engineers
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• v.29 no.1
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• pp.21-31
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• 2003

Determination of operational dimensions and tolerances is complex if there exist inconsistencies between operational and design specifications. Dimension and tolerance charts (D&T charts) have been used to establish the relationships among operational dimensions in complex machining. This chart proves that individual operations can be harmonized when they are interconnected. However, it is hard to generate the chart manually. Because operational dimensions and tolerances must meet the design specifications, the dimensions and tolerances of interconnected operations have to be verified serially for economical operations. In this paper, the chart is automatically generated from the interconnected operations. More importantly, all operational dimensions and tolerances displayed in the chart have been verified by using LP to meet the design specifications. Finally, the chart is converted to an operational routing sheet that contains a detailed process plan along with cutting speed, feed rate, and operational references based on material hardness, surface finish, and tool nose radius.

• Steel and Composite Structures
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• v.34 no.5
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• pp.681-698
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• 2020

The paper addresses contribution to the modeling and optimization of major machinability parameters (cutting force, surface roughness, and tool wear) in finish dry hard turning (FDHT) for machinability evaluation of hardened AISI grade die steel D₃ with PVD-TiN coated (Al₂O₃-TiCN) mixed ceramic tool insert. The turning trials are performed based on Taguchi's L₁₈ orthogonal array design of experiments for the development of regression model as well as adequate model prediction by considering tool approach angle, nose radius, cutting speed, feed rate, and depth of cut as major machining parameters. The models or correlations are developed by employing multiple regression analysis (MRA). In addition, statistical technique (response surface methodology) followed by computational approaches (genetic algorithm and particle swarm optimization) have been employed for multiple response optimization. Thereafter, the effectiveness of proposed three (RSM, GA, PSO) optimization techniques are evaluated by confirmation test and subsequently the best optimization results have been used for estimation of energy consumption which includes savings of carbon footprint towards green machining and for tool life estimation followed by cost analysis to justify the economic feasibility of PVD-TiN coated Al₂O₃+TiCN mixed ceramic tool in FDHT operation. Finally, estimation of energy savings, economic analysis, and sustainability assessment are performed by employing carbon footprint analysis, Gilbert approach, and Pugh matrix, respectively. Novelty aspects, the present work: (i) contributes to practical industrial application of finish hard turning for the shaft and die makers to select the optimum cutting conditions in a range of hardness of 45-60 HRC, (ii) demonstrates the replacement of expensive, time-consuming conventional cylindrical grinding process and proposes the alternative of costlier CBN tool by utilizing ceramic tool in hard turning processes considering technological, economical and ecological aspects, which are helpful and efficient from industrial point of view, (iii) provides environment friendliness, cleaner production for machining of hardened steels, (iv) helps to improve the desirable machinability characteristics, and (v) serves as a knowledge for the development of a common language for sustainable manufacturing in both research field and industrial practice.

• International Journal of Highway Engineering
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• v.10 no.3
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• pp.97-107
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• 2008

I study for design criteria and research about Interchange diverging area of express highway and freeway, the most recent, at interchange diversion of express highway and freeway, design criteria and researches are focus on safety guarantee a point of view movement dynamics of vehicle and road geometric as to transition section, deceleration section, curve radius, nose section, outflow angle etc, that is, design criteria and research of Interchange diverging area have not consider a point of view movement dynamics of vehicle and road geometric and driver, so that I will be focus characteristic of runing speed on trasion curve. and I will consider vehicle running speed characteristics and study problem of Interchange diverging area design criteria. For this study, First, analysis meaning about theory of now design criteria, Second, look at vehicle running speed and traffic accident characteristics of Interchange diverging area, Third, propose new deceleration transition curve design method get along vehicle running speed characteristics of Interchange diverging area. new deceleration transition curve design method put out new outcoums, that is, I definite cause to safety new deceleration transition curve design method better than pressently, used design criteria of Interchange diverging area, especially, deceleration transition curve design criteria produced good result in the running speed 50km/h, 40km/h, that is inertia better than inertia of present used design criteria. and deceleration transition curve is extended better than present transition curve criteria, so that new deceleration transition curve design method safety is good better than the past method safety.