Hasil untuk "Manufactures"

Gürhan Günday, G. Ulusoy, K. Kilic et al.

J. Arthur

Wesley M. Cohen, R. Nelson, John P. Walsh

B. Beamon

Glenn Ellison, E. Glaeser

A. Ragauskas, Charlotte K. Williams, B. Davison et al.

Biomass represents an abundant carbon-neutral renewable resource for the production of bioenergy and biomaterials, and its enhanced use would address several societal needs. Advances in genetics, biotechnology, process chemistry, and engineering are leading to a new manufacturing concept for converting renewable biomass to valuable fuels and products, generally referred to as the biorefinery. The integration of agroenergy crops and biorefinery manufacturing technologies offers the potential for the development of sustainable biopower and biomaterials that will lead to a new manufacturing paradigm.

J. Banhart

U. Zander, B. Kogut

Paul Krugman, A. Venables

Alwyn Young

Paul R. Milgrom, John E. Roberts

Paul R. Milgrom, John E. Roberts

Y. Altintas

Ahmet H. Kirca, S. Jayachandran, W. O. Bearden

E. Herman, N. Chomsky

Эта популярная книга, выдержавшая множество изданий, представляет собой резкую марксистскую критику ведущих (mainstream) масс медиа т.н. «демократических» стран, прежде всего США. В первой главе авторы предлагают теоретическую модель, называемую моделью пропаганды, согласно которой даже в демократических странах, где нет официальной цензуры и СМИ не принадлежат государству, функционирование масс медиа подчиняется механизмам «пропаганды», с той разницей, что они более скрыты. Авторы выделяют пять таких механизмов, или фильтров: (1) структура собственности СМИ и их ориентация на прибыль, (2) зависимость от рекламодателей; (3) зависимость от источников новостей; (4) «flak» - негативная обратная связь и неформальное давление; (5) антикоммунизм как общая идеологическая рамка. Остальные шесть глав представляют собой яркие иллюстрации модели пропаганды в действии: авторы подробно рассматривают такие примеры как освещение американскими СМИ выборов в Латинской Америке, войн во Вьетнаме, Лаосе и Камбодже и др. Авторы приходят к выводу, что Американские СМИ являются мощным идеологическим оружием, однако есть и силы, противостоящие их влиянию.

C. Li, Z. Y. Liu, X. Fang et al.

Abstract Additive manufacturing (AM) has been widely used to fabricate functional metal parts in automobile, aerospace, energy, and medical device industries due to its flexible process capacity including complex geometry, functional graded materials, and free usage of tool. For the two major categories of metal additive manufacturing processes include powder bed fusion (PBF) and directed energy deposition (DED), parts are fabricated through melting of feed stock materials in the form of either powders or wires directly from a CAD model. The unique thermal cycle of metal additive manufacturing is characterized by: (1) rapid heating rate due to high energy intensity with steep temperature gradients; (2) rapid solidification with high cooling rates due to the small volume of melt pool; and (3) melt-back involving simultaneous melting of the top powder layer and re-melting of underlying previously solidified layers. Residual stress caused by the unique thermal cycle in AM is the critical issue for the fabricated metal parts since the steep residual stress gradients generate part distortion which dramatically deteriorate functionality of the end-use parts. This paper comprehensively assessed the current research status on residual stress sources, characteristics, and mitigation. First, the relationship between residual stress and microstructure is highlighted in AM metal parts. Then, the measurement methods and characteristics of residual stress in both as-build metal parts and post-processed ones were summarized. Third, residual stress mitigation and control methods including in-situ and post-process control methods were thoroughly discussed. Furthermore, future work directions are provided in this work.

H. Fayazfar, M. Salarian, A. Rogalsky et al.

Shuo Yin, P. Cavaliere, B. Aldwell et al.

Li Yuan, S. Ding, C. Wen

Recently, the fabrication methods of orthopedic implants and devices have been greatly developed. Additive manufacturing technology allows the production of complex structures with bio-mimicry features, and has the potential to overcome the limitations of conventional fabrication methods. This review explores open-cellular structural design for porous metal implant applications, in relation to the mechanical properties, biocompatibility, and biodegradability. Several types of additive manufacturing techniques including selective laser sintering, selective laser melting, and electron beam melting, are discussed for different applications. Additive manufacturing through powder bed fusion shows great potential for the fabrication of high-quality porous metal implants. However, the powder bed fusion technique still faces two major challenges: it is high cost and time-consuming. In addition, triply periodic minimal surface (TPMS) structures are also analyzed in this paper, targeting the design of metal implants with an enhanced biomorphic environment.

Anbesh Jamwal, R. Agrawal, Monica Sharma et al.

Recent developments in manufacturing processes and automation have led to the new industrial revolution termed “Industry 4.0”. Industry 4.0 can be considered as a broad domain which includes: data management, manufacturing competitiveness, production processes and efficiency. The term Industry 4.0 includes a variety of key enabling technologies i.e., cyber physical systems, Internet of Things, artificial intelligence, big data analytics and digital twins which can be considered as the major contributors to automated and digital manufacturing environments. Sustainability can be considered as the core of business strategy which is highlighted in the United Nations (UN) Sustainability 2030 agenda and includes smart manufacturing, energy efficient buildings and low-impact industrialization. Industry 4.0 technologies help to achieve sustainability in business practices. However, very limited studies reported about the extensive reviews on these two research areas. This study uses a systematic literature review approach to find out the current research progress and future research potential of Industry 4.0 technologies to achieve manufacturing sustainability. The role and impact of different Industry 4.0 technologies for manufacturing sustainability is discussed in detail. The findings of this study provide new research scopes and future research directions in different research areas of Industry 4.0 which will be valuable for industry and academia in order to achieve manufacturing sustainability with Industry 4.0 technologies.