Purpose Additive manufacturing (AM) offers potential solutions when conventional manufacturing reaches its technological limits. These include a high degree of design freedom, lightweight design, functional integration and rapid prototyping. In this paper, the authors show how AM can be implemented not only for prototyping but also production using different optimization approaches in design including topology optimization, support optimization and selection of part orientation and part consolidation. This paper aims to present how AM can reduce the production cost of complex components such as jet engine air manifold by optimizing the design. This case study also identifies a detailed feasibility analysis of the cost model for an air manifold of an Airbus jet engine using various strategies, such as computer numerical control machining, printing with standard support structures and support optimization. Design/methodology/approach Parameters that affect the production price of the air manifold such as machining, printing (process), feedstock, labor and post-processing costs were calculated and compared to find the best manufacturing strategy. Findings Results showed that AM can solve a range of problems and improve production by customization, rapid prototyping and geometrical freedom. This case study showed that 49%–58% of the cost is related to pre- and post-processing when using laser-based powder bed fusion to produce the air manifold. However, the cost of pre- and post-processing when using machining is 32%–35% of the total production costs. The results of this research can assist successful enterprises, such as aerospace, automotive and medical, in successfully turning toward AM technology. Originality/value Important factors such as validity, feasibility and limitations, pre-processing and monitoring, are discussed to show how a process chain can be controlled and run efficiently. Reproducibility of the process chain is debated to ensure the quality of mass production lines. Post-processing and qualification of the AM parts are also discussed to show how to satisfy the demands on standards (for surface quality and dimensional accuracy), safety, quality and certification. The original contribution of this paper is identifying the main production costs of complex components using both conventional and AM.

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This paper provides significant ethnobotanical information on pharmaceutical plant uses, where some degree of acculturation exists, so that there is urgency in recording such data. The aim of this work is to catalogue, document, and make known the uses of plants for folk medicine in Dehloran and Abdanan districts, Ilam Province, Iran. An analysis was made of the species used, parts of the plant employed, preparation methods, administration means, and the ailments treated in relation to pathological groups. A folk botanical survey was carried out from February 2007 to October 2009. The information was collected from 81 persons (60% men and 40% women) in 20 villages. The informants reported data on 122 species, belonging to 49 botanical families, were claimed as medicinal. This work is focused on human medicinal plant uses, which represent 95% of the pharmaceutical uses. The most commonly represented families were Asteraceae (37.5%), Lamiaceae (20.8%), Rosaceae (18.7%), Fabaceae (16.7%) and Apiaceae (14.6%). Some of the uses were found to be new when compared with published literature on ethnomedicine of Iran. The folk knowledge about medicinal plant use is still alive in the studied region, and a number of scarcely reported plant uses has been detected, some of them with promising phytotherapeutical applications. The results of the study reveal that some of species play an important role in primary healthcare system of these tribal communities. Key words: Medicinal plants, ethnobotany, folklore plant, Ilam IntroductionThe Ilam province is situated on the west of Iran. This province known as "Thyme land or locally as Sarzamin-e-Avishan" and it is principally a mountainous region with plains following the direction of West Zagros range. It borders Khuzestan province in the south, Lurestan province in the east, Kermanshah province in the north and Iraq in the west with 425 kms of common border (Figure 1). Ilam is located between latitude 31º 58´ to 34º 15´ N and longitude 45º 24´ to 48º 10´ E. It occupies an area of 19,086 km². The elevation range is between 50 m above sea level in the south to 3060 m above sea level in the west province (Kabirkooh Mountain).The climate of the region is influenced with its varied elevation. Annually, it generally rains 200 mm in the south and 500 mm in the north and the period of winter, the minimum temperature can reach -15ºC in north and summer is day with maximum temperature between 45ºC in south. Humidity is generally high especially in the winter (Dec-Mar) months (Ilam Meteorology Office, 2010).The natural vegetation is rangeland and oak forest. Flora of Ilam province is extremely rich with about 1000 species of plant (Mozaffarian, 2008). The present study focused on the current status of knowledge of folk medicine in Abdanan and Dehloran districts. Plants have always had an important role to play in medicine and public health. The knowledge on the use of medicinal plants was acquired by trial and error and handed on from generation to generation (Ghorbani, 2005). Never...

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The interim restorations play an important role in protection of hard and soft oral tissue and providing the critical function and esthetics before the final restoration replacing. Temporary restorations must have sufficient flexural strength to resist deformation during mastication force. Moreover, sufficient surface hardness is also necessary to resist abrasion. The color stability of materials is considered as an important clinical criterion, specifically in esthetics zone. Several materials have been applied to improve ‏the flexural strength and surface hardness for representing clinical success. Zirconia nanoparticles show desirable features, such as high hardness, biocompatibility, and favorable color because of its white color. ‏It seems that the addition of the nano zirconia to acrylic resins can be the appropriate method for improving interim restoration.

Active vibration control using time delay for a cantilever beam is developed in this paper. The equation of motion of the system is developed using the discrete standard formulation, and the discrete quadratic function is used to design the controller. The original contribution in this paper is using a genetic algorithm to determine the optimal time delay feedback for active vibration control of a cantilever beam. Simulations of the beam demonstrated that the genetic algorithm correctly identified the time delay which produced the quickest attenuation of unwanted vibrations for both mode one and mode two. In terms of frequency response, the optimal time delay for both modes reduced the resonant amplitude. In a mixed mode situation, the simulation demonstrated that an optimal time delay could be identified.

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