Browsing by Author "Wu, Yi-Ju"

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An Automated IoT Visualization BIM Platform for Decision Support in Facilities Management
(2018-07-01)
Chang, Kai-Ming
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Dzeng, Ren-Jye
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Wu, Yi-Ju
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土木工程學系
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Department of Civil Engineering
Building information modeling (BIM) is the digital representation of physical and functional characteristics (such as geometry, spatial relationship, and geographic information) of a facility to support decisions during its life cycle. BIM has been extended beyond 3D geometrical representations in recent years, and now includes time as a fourth dimension and cost as a fifth dimension, as well as such other applications as virtual reality and augmented reality. The Internet of Things (IoT) has been increasingly applied in various products (smart homes, wearables) to enhance work productivity, living comfort, and entertainment. However, research addressing the integration of these two technologies (BIM and IoT) is still very limited, and has focused exclusively on the automatic transmission of sensor information to BIM models. This paper describes an attempt to represent and visualize sensor data in BIM with multiple perspectives in order to support complex decisions requiring interdisciplinary information. The study uses a university campus as an example and includes several scenarios, such as an auditorium with a dispersed audience and energy-saving options for rooms with different functions (mechanical/electrical equipment, classrooms, and laboratory). This paper also discusses the design of a common platform allowing communication among sensors with different protocols (Arduino, Raspberry Pi), the use of Dynamo to accept sensor data as input and automatically redraw visualized information in BIM, and how visualization may help in making energy-saving management decisions.
Insight into the Catalytic Effects of Open Metal Sites in Metal - Organic Frameworks on Hydride Dehydrogenation via Nanoconfinement
(2019-10-07)
Wu, Yi-Ju
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Wang, Cheng-Yu
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材料科學與工程學系
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Department of Materials Science and Engineering
Chemical hydride ammonia borane (AB, NH3BH3) draws attentions as a hydrogen storage medium for its high hydrogen capacity (19.6 wt %) and good thermal stability at ambient environments. However, high hydrogen generation temperatures and slow kinetics limit AB practical applications. One way to overcome the obstacles is the nanoconfinement effect: AB incorporated with porous materials has facilitated dehydrogenation process. However, the mechanism is still under debate, and several factors have been proposed, like hydride nanosize or catalytic environments controlled/provided by microporous supports. In this research, metal organic frameworks (MOFs) of Cu-BDC (BDC = benzenedicarboxylate) with/without manipulated active open metal sites by solvent removal/capping are applied for AB thermolysis via nanoconfinement. Both AB@MOFs show the same dehydrogenation peaked temperature regardless of catalytic environments, strengthening the theory that high surface tension from hydride nanosize controlled by MOF microporosity results in reduced dehydrogenation temperature. In addition, compared to solvent-capped MOFs, Cu-BDC with copper open metal sites eliminates byproduct emission and hence increases hydrogen yield from AB and also decreases dehydrogenation activation energy considerably. However, short cycle life due to copper reduction is observed in desolvated Cu-BDC, while lowered dehydrogenation temperature can be kept in solvated MOFs. In general, we clarify possible mechanisms and factors to hydride nanoconfinement and catalysis that improve AB dehydrogenation temperature and kinetics and provide new strategies for future hydride composite materials design.
Observation and simulation of hydrogen storage via spillover
(2018-09-01)
Wang, Cheng-Yu
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Chang, Cheng-Wei
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Wu, Yi-Ju
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Lueking, Angela D.
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材料科學與工程學系
Hydrogen spillover refers to catalytic dissociation of hydrogen molecules followed by surface diffusion to the catalytic support. This mechanism has been proposed as a means to initiate hydrogen storage at ambient temperature. When catalytic dissociation of hydrogen is used to initiate room temperature hydrogen storage, this initiates weak chemisorption. High variations in experimental uptake, combined with theoretical calculations that are inconsistent with this mechanism, have made this concept controversial. Here, we review hydrogen uptake in porous carbon and metal-organic frameworks (MOFs), with emphasis on spectroscopic evidence of atomic hydrogen bound to the surface and resolution of discrepancies between experimental and theoretical studies. We conclude with a perspective of hydrogen spillover for future material design, hydrogen storage, and fundamental understanding of a process that is crucial for adsorption and catalysis.