Client engagement and building design: the view from actor–network theory

The accommodation of client expectations in a construction project is challenging. This is, in part, because a client is rarely a single individual and their expectations are rarely static. This paper uses the actor–network theory (ANT) concepts of problematization, enrolment and durability to explore client engagement. The contribution of ANT lies in its (ontological) model of distributed agency, fluid heterogeneous networks and associated effects. A pilot study of a single building project provides an opportunity to theorize the different ways that clients engage in the development of a building. Client engagement differs with the direct versus mediated presence of different client actors, with the devices used to mediate negotiations and with the relative materiality of the network. The findings move the discussion of client engagement beyond the usual calls for better integration to an awareness of the mechanisms by which clients engage. Some decisions are fixed in material objects, while others remain open to ongoing negotiation. There is a need for explicit and continuous interaction and better awareness of when and how decisions are fixed. This would help all participants to deal with the complex and dynamic landscape of people, organizations and interests usually labelled as ‘client’.     

ALS-Linked P56S-VAPB Mutation Impairs the Formation of Multinuclear Myotube in C2C12 Cells

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive neurodegenerative disorder that affects upper and lower motor neurons. Since motor neurons target skeletal muscles, the maintenance system of muscles is disturbed in ALS; however, the mechanism by which this occurs is unknown. In the present study, we investigated the effects of ALS-associated P56S-vesicle-associated membrane protein-associated protein B (VAPB) (P56S-VAPB) on the IRE1-XBP1 pathway, which is involved in the unfolded protein response (UPR) of the mouse myoblast cell line (C2C12 cells). Experiments with C2C12 cells transfected with wild-type wt-VAPB and P56S-VAPB expression vectors showed reduced myotube formation and aberrant myonuclear position in cells expressing P56S-VAPB. Activity of the IRE1-XBP1 pathway in the cells visualized with the ERAI system revealed that the pathway was disrupted in cells expressing P56S-VAPB, whereas the IRE1-XBP1 pathway activity was enhanced in the differentiation process of normal C2C12 cells. These results suggest that disruption of the IRE1-XBP1 pathway is a cause for the reduced myotube formation in P56S-VAPB-expressing cells. The expression level of the VAPB protein has been reported to be reduced in the neurons of patients with ALS. Therefore, it is expected that the IRE1-XBP1 pathway is also impaired in muscle tissues of patients with ALS, which causes a disturbance in the muscle maintenance system.     

Microstructural evolution in two-phase alloys processed by high-pressure torsion

The Zn-22 % Al eutectoid alloy and the Pb-62 % Sn eutectic alloy were processed by high-pressure torsion (HPT) over a range of experimental conditions. Both alloys exhibit similar characteristics with significant grain refinement after processing by HPT but with a reduction in the hardness values by comparison with the initial unprocessed conditions. It is shown that there are generally smaller grains at the edges of the disks by comparison with the disk centers. The hardness results in these two alloys are mutually consistent, but they are different from those generally reported for conventional single-phase materials. The significance of this difference is examined.     

Structure and void fraction in a liquid slug for gas–liquid two‐phase slug flow

The distribution of gas and liquid in a gas–liquid two‐phase slug flow was measured using semi‐supermultiple point‐electrode probes. Based on the measurements, the wake zone behind a gas slug and the low void‐fraction zone in a liquid slug were defined, and the void fractions of the two zones were determined. The data revealed that the void fraction of the wake zone increased with superficial gas velocity, yet was virtually independent of superficial liquid velocity. Nondimensional head was proposed as an informative characteristic of this system, accounting for the momentum change of the liquid in the wake zone. It was clarified that the nondimensional head was closely related to the void fraction of the wake zone. A good practical relationship was found between the nondimensional head and the lengths of a swelling liquid‐front zone and the wake zone. Furthermore, empirical correlations were proposed for the void fraction in the wake zone, the mean void fraction in the liquid slug, and the lengths of the swelling liquid‐front zone and the wake zone. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(4): 257–271, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10029     

Creep-fatigue interaction properties of nickel-based superalloy 617

High-temperature fatigue properties were investigated for a nickel-based superalloy 617 as a typical candidate material for high-temperature components using an advanced ultra super critical (A-USC) power plant. Creep-fatigue data obtained by strain-controlled tests at 700 ? C was analyzed for the superalloy 617 focused on position of hold at peak strain in comparison with continuously cycled tests. The fatigue life was the shortest with the hold tensile strain wave, which showed mainly intergranular fractu...     

Proportional fair scheduling with superposition coding in a cellular cooperative relay system

Many works have tackled on the problem of throughput and fairness optimization in cellular cooperative relaying systems. Considering firstly a two-user relay broadcast channel, we design a scheme based on superposition coding (SC) which maximizes the achievable sum-rate under a proportional fairness constraint. Unlike most relaying schemes where users are allocated orthogonally, our scheme serves the two users simultaneously on the same time-frequency resource unit by superposing their messages into three SC layers. The optimal power allocation parameters of each SC layer are derived by analysis. Next, we consider the general multi-user case in a cellular relay system, for which we design resource allocation algorithms based on proportional fair scheduling exploiting the proposed SC-based scheme. Numerical results show that the proposed algorithms allowing simultaneous user allocation outperform conventional schedulers based on orthogonal user allocation, both in terms of throughput and proportional fairness. These results indicate promising new directions for the design of future radio resource allocation and scheduling algorithms.     

Low-Temperature Synthesis of Nanocrystalline Zinc Titanate Materials with High Specific Surface Area

Nanocrystalline zinc titanate (ZnTiO₃) was synthesized at low temperatures through the combination of a sol–gel processing and a polymer binder method. ZnTiO₃ powders of ∼5 nm in size were obtained by heating pastes, which were composed of a Zn-Ti methanolic solution containing acetylacetone and an organic polymer binder, at 500°C in air. Thermal decomposition behavior of the pastes was analyzed by thermogravimetry-differential thermal analysis. Crystallinity of ZnTiO₃ was examined by transmission electron microscopy. The BET measurement revealed that the powders had a relatively high specific surface area of 106 m²/g.