633 research outputs found
Developing new heat pump system to improve indoor living space in senior long-term care house
The issue of an aging population is becoming increasingly acute in Taiwan; in 2018, seniors comprised over 14 % of the total population. The quality of care for senior citizens hinges on the ability of long-term care facilities to create comfortable living spaces while ensuring energy efficiency by reducing electricity consumption, thereby providing them with an environment for aging in an active and positive way. This study proposes a new heat pump system that offers a cold source in the summer and a heat source in the winter. In addition, the air-conditioning and ventilation rates required for comfort in indoor living spaces are established to ensure the high quality of the care spaces in these types of institutions. The results after installation of the heat pump system were as follows: (1) Performance of the heat pump system: the inlet temperature of the heat pump chilled water was maintained at 7-10 °C, and the outlet temperature, at 42-54 °C. (2) Energy efficiency: Based on a 95 % confidence interval, the average annual electricity consumption was 32.65 kwh/day, which was 32.65 % of the prior consumption level; the reduction of 67.35 % is comparable to those of most heat pump systems. (3) Improvement of the indoor environment: In the hottest scenario, the indoor temperature was reduced by 3 °C and the relative humidity to 55-65 %, which fall within comfortable ranges. After the heat pump system was introduced, significant improvements in ventilation, air quality and comfort were noted, as well as significant improvement in average total satisfaction scores. All improvements reached statistical significance. The overall objective of the system is to enhance the environmental quality in long-term senior care facilities and make them healthier and more energy efficient
Seismic Proofing Capability of the Accumulated Semiactive Hydraulic Damper as an Active Interaction Control Device with Predictive Control
The intensity of natural disasters has increased recently, causing buildings’ damages which need to be reinforced to prevent their destruction. To improve the seismic proofing capability of Accumulated Semiactive Hydraulic Damper, it is converted to an Active Interaction Control device and synchronous control and predictive control methods are proposed. The full-scale shaking table test is used to test and verify the seismic proofing capability of the proposed AIC with these control methods. This study examines the shock absorption of test structure under excitation by external forces, influences of prediction time, stiffness of the auxiliary structure, synchronous switching, and asynchronous switching on the control effects, and the influence of control locations of test structure on the control effects of the proposed AIC. Test results show that, for the proposed AIC with synchronous control and predictive control of 0.10~0.13 seconds, the displacement reduction ratios are greater than 71%, the average acceleration reduction ratios are, respectively, 36.2% and 36.9%, at the 1st and 2nd floors, and the average base shear reduction ratio is 29.6%. The proposed AIC with suitable stiffeners for the auxiliary structure at each floor with synchronous control and predictive control provide high reliability and practicability for seismic proofing of buildings
Developing Dynamic Digital Image Techniques with Continuous Parameters to Detect Structural Damage
Several earthquakes with strong magnitude occurred globally at various locations, especially the unforgettable tsunami disaster caused by the earthquake in Indonesia and Japan. If the characteristics of structures can be well understood to implement new technology, the damages caused by most natural disasters can be significantly alleviated. In this research, dynamic digital image correlation method for using continuous parameter is applied for developing a low-cost digital image correlation coefficient method with advanced digital cameras and high-speed computers. The experimental study using cantilever test object with defect control confirms that the vibration mode calculated using this proposed method can highly express the defect locations. This proposed method combined with the sensitivity of Inter-Story Drift Mode Shape, IDMS, can also reveal the damage degree of damage structure. These test and analysis results indicate that this proposed method is high enough for applying to achieve the object of real-time online monitoring of structure
An energy balancing strategy based on Hilbert curve and genetic algorithm for wireless sensor networks
A wireless sensor network is a sensing system composed of a few or thousands of sensor nodes. These nodes, however, are powered by internal batteries, which cannot be recharged or replaced, and have a limited lifespan. Traditional two-tier networks with one sink node are thus vulnerable to communication gaps caused by nodes dying when their battery power is depleted. In such cases, some nodes are disconnected with the sink node because intermediary nodes on the transmission path are dead. Energy load balancing is a technique for extending the lifespan of node batteries, thus preventing communication gaps and extending the network lifespan. However, while energy conservation is important, strategies that make the best use of available energy are also important. To decrease transmission energy cost and prolong network lifespan, a three-tier wireless sensor network is proposed, in which the first level is the sink node and the third-level nodes communicate with the sink node via the service sites on the second level. Moreover, this study aims to minimize the number of service sites to decrease the construction cost. Statistical evaluation criteria are used as benchmarks to compare traditional methods and the proposed method in the simulations.Web of Scienceart. ID 572065
Energy dissipation behaviours and seismic reduction performance of a proposed velocity and displacement dependent hydraulic damper (VDHD)
A new oil‐pressure Velocity and Displacement Dependent Hydraulic Damper (VDHD) is proposed by adding an additional Relief Valve parallel to the Throttle Valve with a different aperture size. This objective is to obtain an adaptive control by changing the damping coefficient of the VDHD for better control of structural movement during earthquake. In order to simulate its actual energy elimination, a mathematical analysis model is developed based on the Maxwell Model, which is modified by adding a serial friction model and a small damper parallel to the friction model in this study. The mathematical simulated results are compared with the actual energy‐dissipating behaviours of this proposed damper. The comparison shows that this proposed mathematical modelling could accurately simulate the relation of force and displacement as well as the relation of force and velocity during the process of energy dissipation. In addition, results of both the laboratory shaking table test and simulation analyses are used to test and verify the seismic reduction performance of this proposed damper. The experimental and simulation results show that in spite of the magnitude of the earthquake, the proposed VDHD device has a superior effect on the control of structural displacement by achieving effective acceleration reduction.
Santrauka
Siūlomas naujas hidraulinis i greiti ir poslinki reaguojantis slopintuvas (HGPS), sukurtas prie droselinio vožtuvo su kintama apertūra pridejus atbulini vožtuva. Buvo siekiama užtikrinti geresne adaptyvia konstrukcijos judejimo žemes drebejimo metu kontrole keičiant HGPS slopinimo koeficienta. Norint modeliuoti tikraji energijos pašalinima, buvo sukurtas matematinis modelis, pagristas Maksvelo modeliu. Šis modelis buvo pakeistas prie trinties modelio pridejus nuosekluji trinties modeli ir nedideli slopintuva. Matematinio modeliavimo rezultatai lyginami su tikraja siūlomo gesintuvo energijos sklaida. Palyginimas rodo, kad matematinio modeliavimo rezultatai atitinka tikraja siūlomo gesintuvo elgsena. Lyginant skaičiavimo rezultatus su eksperimentiniais matyti, kad siūlomas matematinis modeliavimas leidžia tiksliai išreikšti jegos ir poslinkio bei jegos ir greičio ryšius, susidarančius energijos sklaidos metu. Laboratoriniai rezultatai, gauti naudojant vibracini stala, ir modeliavimo rezultatai taikomi tirti bei tikrinti siūlomo gesintuvo itaka mažinant seismines konstrukcijos charakteristikas. Eksperimentiniai ir modeliavimo rezultatai rodo, kad nepaisant žemes drebejimo laipsnio, siūlomas gesintuvas labai pagerina konstrukcijos poslinkiu kontrole efektyviai mažindamas judejimo pagreiti.
First Published Online: 10 Feb 2011
Reikšminiai žodžiai: HGPS, Maksvelo modelis, diskretusis sprendinys, pasyvusis energijos skaidos prietaisas, vibracinio stalo bandymas, modeliuojamas konstrukcijos reakcijos mažinima
Experimental Validation of Numerical Model for Bi-Tilt-Isolator
Bi-Tilt Isolator (BTI) is composed of bi-tilt beveled substrate and slider. The advantages of BTI are that the maximum upload seismic force of structure can be easily controlled and displacement of isolation layer will be reduced. Sliding force, friction force, and impulse force are caused in the slanting process of BTI, nonlinear behavior. A nonlinear mathematical model is derived based on the sliding upwards, sliding downwards, and transition stages. Then, BTI element of nonlinear analysis program, GENDYN, is developed by the fourth-order Runge-Kutta method, the discretized ordinary differential equation for three movement stages of BTI. Then, test set-up of superstructure installed with BTI is tested and recorded the real displacement and acceleration responses under conditions of full lubrication, mild lubrication, and without lubrication between interface of bi-tilt beveled substrate and slider with three various initial displacements. The comparison of simulation results and test results shows the following: (1) root mean square error is below 1.35% for WD40 sprayed, 0.47% for WD40 whipped, and 0.54% for without lubrication, respectively; (2) the maximum root mean square error for simulating with cubic polynomial function of friction is much less than those of constant friction except conditions of full lubrication, which are not affected by kinetic friction force; (3) application of cubic polynomial function for simulating friction of BTI with three different lubricated conditions can perform very fine simulation results, compared with the test results. This proposed mathematical model and BTI element of GENDYN program, using cubic polynomial function of friction, perform fine simulation capability to assess nonlinear isolation effect of structure installed with BTI
Developing a neutral equilibrium device as dynamic virtual piers for an emergency relief bridge
Every year, many natural disasters strike Taiwan, destroying bridges and disrupting traffic. To allow shipping of relief provisions and salvage, fabricated steel bridges are often used to construct emergency relief bridges. This kind of bridge must meet strength and functionality requirements. Strength depends on the materials used, while functionality depends on displacement control. These two requirements affect the section design of the bridge deck. In order to quickly build a light-weight bridge for emergency relief with displacement control, a neutral equilibrium mechanism is proposed and developed to control the deflection of an emergency relief bridge. A neutral equilibrium mechanism is a system with an internal control mechanism that can actively change the internal structure. Structural transformation causes the size variation of the action force to respond to continuous changes in bridge deflection. This mechanism can expand the effective span of the bridge, maintain its strength and functionality, and increase the convenience of building and mobility. Experimental results reveal that a virtual pier at the center of a bridge with this proposed mechanism installed can control vertical deflection caused by vehicles carrying heavy loads. Test and analysis records also reveal that the vertical displacement at the center of a bridge with the neutral equilibrium mechanism installed is close to zero. The practicality of this neutral equilibrium mechanism has been verified by experiment
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Location-based Data Analysis of Visitor Structure for Recreational Area Management
This work presents a location-based data analysis framework for profiling visitors structures. In terms of recreational area management, understanding visitors’ structure and popularity is important. Traditionally, visitors monitoring with automatic counting devices has drawbacks of inaccurate visitors counting. In this work, compared to automatic counting devices, we use Wi-Fi tracking as the main method to count visitors, which provides a fairly precise picture of visitor structures. Moreover, we deliver rich analytic functions in this framework and we present the functionality with visitor data collected from Guanyinshan Visitor Center. This framework not only standardizes visitor counting process but also facilitates a profound analysis of visitor structures.
Key Words:
Guanyinshan Visitor Center, Wi-Fi trackin
Anti-Inflammatory Activities of Cinnamomum cassia Constituents In Vitro and In Vivo
We have investigated the anti-inflammatory effects of Cinnamomum cassia constituents (cinnamic aldehyde, cinnamic alcohol, cinnamic acid, and coumarin) using lipopolysaccharide (LPS)-stimulated mouse macrophage (RAW264.7) and carrageenan (Carr)-induced mouse paw edema model. When RAW264.7 macrophages were treated with cinnamic aldehyde together with LPS, a significant concentration-dependent inhibition of nitric oxide (NO), tumor necrosis factor (TNF-α), and prostaglandin E2 (PGE2) levels productions were detected. Western blotting revealed that cinnamic aldehyde blocked protein expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), nuclear transcription factor kappa B (NF-κB), and IκBα, significantly. In the anti-inflammatory test, cinnamic aldehyde decreased the paw edema after Carr administration, and increased the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in the paw tissue. We also demonstrated cinnamic aldehyde attenuated the malondialdehyde (MDA) level and myeloperoxidase (MPO) activity in the edema paw after Carr injection. Cinnamic aldehyde decreased the NO, TNF-α, and PGE2 levels on the serum level after Carr injection. Western blotting revealed that cinnamic aldehyde decreased Carr-induced iNOS, COX-2, and NF-κB expressions in the edema paw. These findings demonstrated that cinnamic aldehyde has excellent anti-inflammatory activities and thus has great potential to be used as a source for natural health products
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