Hospital is of interest when consider its especial function. Because of the obviously different between the normal residential buildings, the requirement of hospitals’ indoor climate strictly differs from other buildings. The author starts this report by briefly stating the building construction currently. Surrounded the topic of thermal comfort and energy consumption, many suggestion and options came out in this report to develop a better condition. Firstly, the introduction of the hospital buildings requires the background of the hospital object and the purpose to this report will be stated. Secondly, the simulation tool and how to use this tool simulate our real case are introduced. Then, the summer case is investigated by this tool after the model is proved to be validated. Finally, the improvement of establishing a better indoor environment is raised and the results of improvement and conclusion can be found. The final result will show the optimal solution that discovered by this study after compared different alternatives carefully.

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In this study, a pilot-scale Regenerative Thermal Oxidizer (RTO) was used to test its performance for volatile organic compound (VOC) destruction and degree of thermal energy conservation. The RTO is electrically heated and contains two 0.5 m ¡Ñ 0.5 m ¡Ñ 2.0 m (L ¡Ñ W ¡Ñ H) columns both packed with gravel particles of 1.0 cm in diameter to a height of 1.4 m. The bed has a void fraction of 0.415. The purpose of this study is to establish the influencing operating conditions and to improve the technique for further applications. Experiments include two phases: (1) energy conservation test with no VOC in the influent air stream , and (2) VOC destruction test with influent air streams containing one of the three VOCs: isopropyl alcohol, acetone, and xylene. Phase 1 experiments were conducted in the maximum gravel temperatures (Tmax) of 402-704 oC, superficial gas velocities (Ug, evaluated at ambient temperatures of 25-30 oC) of 0.15-0.50 m/s, and bed shift times (ts) of 0.5-2.0 min. Results indicate that the temperature raise (

Two-dimensional graphene, a single layer of graphite, has emerged as an excellent candidate for future electronic material due to its unique electronic structure and remarkably high carrier mobility. Even higher carrier mobility has been demonstrated in graphene devices using hexagonal boron nitride as an underlying dielectric support instead of silicon oxide. Interestingly, both graphene and boron nitride exhibit superior thermal properties, therefore may potentially offer a solution to the increasingly severe heat dissipation problem in nanoelectronics caused by increased power density. In this thesis, we focus on the investigation of the thermal properties of graphene and hexagonal boron nitride. First, scanning thermal microscopy based on a sub-micrometer thermocouple at the apex of a microfabricated tip was employed to image the temperature profiles in electrically biased graphene devices with ~ 100 nm scale spatial resolution. Non-uniform temperature distribution in the devices was observed, and the "hot spot" locations were correlated with the charge concentrations in the channel, which could be controlled by both gate and drain-source biases. Hybrid contact and lift mode scanning has enabled us to obtain the quantitative temperature profiles, which were compared with the profiles obtained from Raman-based thermometry. The temperature rise in the channel provided an important insight into the heat dissipation mechanism in Joule-heated graphene devices. Next, thermal conductivity of suspended single and few-layer graphene was measured using a micro-bridge device with built-in resistance thermometers. Polymer-assisted transfer technique was developed to suspend graphene layers on the pre-fabricated device. The room temperature thermal conductivity values of 1-7 layer graphene were measured to be lower than that of bulk graphite, and the value appeared to increase with increasing sample thickness. These observations can be explained by the impact of the phonon scattering by polymer residue remaining on the sample surfaces. Lastly, thermal conductivity of few-layer hexagonal boron nitride sample was measured by using the same device and technique used for suspended graphene. Measurements on samples with different suspended lengths but similar thickness allowed us to extract the intrinsic thermal conductivity of the samples as well as the contribution of contact thermal resistance to the overall thermal measurement. The room temperature thermal conductivity of 11 layer sample approaches the basal-plane value reported in the bulk sample. Lower thermal conductivity was measured in a 5 layer sample than an 11 layer sample, which again supports the polymer effect on the thermal transport in few-layer hexagonal boron nitride. / text

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Stress induced void formation in Cu interconnects, due to thermal stresses generated during the processing of semiconductors, is an increasing reliability issue in the semiconductor industry as Cu interconnects are being downscaled to follow the demand for faster chip speed. In this work, 1.8 micron and 180 nm wide Cu interconnects, fabricated by Freescale Semiconductors, were subjected to thermal cycles, in-situ in the TEM, to investigate the stress relaxation mechanisms as a function of interconnect linewidth. The experiments show that the 1.8 micron Cu interconnect lines relax the thermal stresses through dislocation nucleation and motion while the Cu interconnect 180 nm lines exhibit void formation. Void formation in 180 nm lines occurs predominantly at triple junctions where the Ta diffusion barrier meets a Cu grain boundary. In order to understand void formation in 180 nm lines, the grain orientation and local stresses are determined. In particular, Nanobeam Diffraction (NBD) in the TEM is used to obtain the diffraction pattern of each grain, from which the crystal orientation is evaluated by the ACT (Automated Crystallography for TEM) software. In addition, 2D Finite Element Method (FEM) simulations are performed using the Object Oriented Finite Modeling (OOF2) software to correlate grain orientation with local stresses, and consequently void formation. According to the experimental and simulation results obtained, void formation in 180nm Cu interconnects does not seem to be solely dependent on local stresses, but a combination of diffusion paths available, stress gradients and possibly the presence of defects. In addition, based on the in-situ TEM observations, void growth seems to occur through grain boundary and/or interfacial diffusion. However, in-situ STEM observations of fully opened voids post-failure show pileup of material at the Cu grain surfaces. This means that surface or interface diffusion is also very active during void growth in the presence of thermal stresses.

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