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Nitrobenzene oxidation was executed by means of a novel process, wherein persulfate anions were combined with Ag/PbO semiconductors activated by ultrasound. Batch-wise experiments were accomplished to investigate the influence of ultrasonic power intensity, persulfate concentrations, and Ag/PbO dosages, respectively, on the nitrobenzene removal efficiency. Owing to pronounced scavenging effects exhibited by benzene, ethanol, and methanol individually, the principal oxidizing agent was sensibly presumed to be sulfate radicals, which could be generated from persulfate anions activated with sonocatalysis of Ag/PbO. The optimal conditions for complete elimination of nitrobenzene were found as follows: ultrasonic power intensity = 240 W cm–2, T = 318 K, persulfate concentration = 70 mM, and Ag/PbO dosage = 1.3 g L–1. As far as oxidation pathways are concerned, nitrobenzene was initially transformed into hydroxycyclohexadienyl radicals, followed by the formation of 2-nitrophenol or 4-nitrophenol. Denitration of nitrophenol compounds makes the synthesis of phenol, which was sequentially converted into hydroquinone and p-benzoquinone.

Satisfying customer demand represents a challenge for product designers because manufacturers must clearly understand what design aspects meet customer desires to obtain a competitive advantage in the market. However, little empirical articles focus on examining robust design capability connects new technology and aesthetics, matches the manufacturing process, and meets customer needs. This paper addresses gaps and proposes a conceptual model that assesses the relationship among internal cross-functional coordination, external solid supply chains, and customer orientation, and design capability. The conceptual model was tested by 240 self-administrated questionnaires from contract manufacture practitioners in Taiwan and analysed by structural equation modelling (SEM). The results provide evidence that interfunctional coordination is a basis for building more effective supply chain architecture and customer orientation. Additionally, supply chain and customer orientation positively affect design capability, and design capability plays the critical role as a mediator in the improvement of new product performance. Implications are discussed.

Inter-comparison on the chemical characteristics, spatiotemporal variation, and source originality of atmosphere PM10at the coastal regions and offshore islands of subtropical region in East Asia was investigated. A total of six sampling sites including three coastal and three island sites over the Minjiang estuary were selected for simultaneously manually sampling PM10to investigate the differences of coastal and island PM10concentration, chemical properties, and emission sources. After sampling, an ion chromatographer (IC) was used to analyze the concentration of major anions (F−, Cl−, SO42−, and NO3−) and cations (NH4+, K+, Na+, Ca2+and Mg2+). The metallic elements (Na, Ca, Al, Fe, Mg, K, Zn, Cr, Ti, Mn, Ni, Pb, and Cd) of PM10were measured with an inductively coupled plasma-atomic emission spectrometer (ICP-AES). The carbonaceous contents, including elemental, organic, and total carbons (OC, EC, and TC), of PM10were analyzed with an elemental analyzer (EA). The source apportionment of PM10was further resolved by a receptor model based on chemical mass balance (CMB). Field measurement results showed that high concentrations of PM10(102 ± 25 μg/m3) were commonly observed from late fall to early winter. The PM10concentration showed a consistently descending trend from the west coastline to the far east islands, with the highest PM10concentration at the coastal site (Site HQ) and the lowest at the far east island site (Site DY) in all seasons. Secondary inorganic aerosols (SIAs) and crustal materials were two most abundant compounds in PM10. Increasing anthropogenic trace elements was commonly observed in spring and winter, while northern monsoons were blown. High OC/EC ratios showed that secondary organic aerosols (SOAs) could be formed in the atmosphere of Minjiang estuary. Results from CMB receptor modeling indicated that the major sources of atmospheric PM10at the coastal and offshore island regions of the Minjiang estuary were soil dusts (13–33%), secondary aerosols (15–30%), transport emissions (11–17%), sea salts (8–27%), and agricultural debris burning (2–8%). Particularly, during the poor air quality periods, a rising contribution of industrial emissions (1–16%) was resolved, suggesting that atmospheric PM10over the Minjiang estuary was mainly attributed to cross-boundary transport rather than local emissions.

Over the recent years, the continued increase in the number of particles in air has become a public concern. This problem can be addressed by using nanofibers to filter fine particles. However, nanofibers possess complex characteristics. As such, the effects of surface charge require further studies. In this study, the surface voltages of nanofibers were analyzed with an electrometer after these fibers were charged through corona discharge to investigate the mechanism of filtration. Results indicated that the surface voltage of 2.0% TiO2polyacrylonitrile fibers (TPFs) can reach up to 0.97 kV and then decrease to 0.60 kV after 96 h. Particles were optimally removed by charged polyacrylonitrile fibers (PFs) and TPFs. Particle penetration decreased by 71% of TPF and 36% of PF. Scanning Electron Microscopy and Nitrogen adsorption/desorption isotherms revealed that increasing the surface area and roughness of these materials are more favorable for charge maintenance to promote particle removal. Our research could provide an in-depth understanding of the effects of surface charge on particle removal and show how systems can be optimized for further applications.

The hydrolytic properties of LiAlO2 (LAO) are important factors for its applications on LED fabrication. During soft pad polishing process, the H2O in the slurry is deleterious for LAO surface polishing results. The current study develops a material removal rate model for materials with hydrolysis reaction to predict the result of polishing process.The current research conducts the experimental studies to investigate the material removal rate and its mechanism during the soft pad polishing process. In the experimental study, the hydrolytic properties of LAO have been tested to understand the hydrolysis speed with different operation parameters to assist the development of the theoretical model. Also the material removal rates of LAO with hydrolytic property have been measured under different soft pad polishing operating conditions. The experimental results provide the hydrolytic properties of LiAlO2 to understanding of the mechanism on polishing process.

Arid riverbed is an important source of Aeolian dust to influence the atmosphere of nearby village or downtown. In general, Aeolian dust pertains to wind activity in the study of geology, environment and meteorology on particle suspension. This field study set the horizontal/vertical sampling system up in order to investigate the Aeolian dust dimensional distribution properties from the riverbed of the Jhuoshuei River. In addition, the study utilized the unmanned aerial vehicle (UAV) imagery to discriminate the covering condition of riverbed. The results revealed that the percentage of riverbed covering conditions, including bare zone, wetlands, green covering and water covering was about 50.1, 15.7, 16.8 and 17.4%, respectively, on January 5th, 2011. Two Aeolian dust cases from riverbed were measured on November 26th, 2010 and January 15th, 2011. First sampling case was under slower wind speed, and the total particulate matter (PM) concentration in vertical sampling was almost decreased with increasing sampling height, however, the phenomena of second case (faster wind speed) was just on the contrary. Besides, Aeolian dust was distributed in a bimodal or a multimodal curve, and the main peak size was above 10 µm. Mode size of suspension particle diameter was increased as the wind speed increased (14.8 µm/ first case; 21.3 µm/ second case). The total mass concentration ratio of south site to source site (one meter height) was about 1:9 in first case and about 1:3 in second case. Comparing with those two cases, the faster the wind is, the shorter the surface roughness height is (3.08 mm/ first case; 1.07 mm/ second case). Besides, as the wind speed increasing, the friction velocity was also increased (0.33 m s−1/ first case; 0.68 m s−1/ second case). Consequently, this study clued the spatial variability of river dust events, which can further aid the site investigating, forecasting and preventing of dust influences.

•Microporous ZSM-5 and mesoporous MCM-41 loaded with TiO2were synthesized and compared.•Uniform design was adopted to study four factors of photocatalytic degradation process in eleven levels.•The predicted results of uniform design agreed with the actual results of single factor experiments.•The biological toxicity of oxytetracycline and its intermediates was assessed by inhibition rate of Escherichia coli, which linearly decreased with increased OTC degradation efficiency.•The inhibition rate was calculated from the biomass at the stationary growth phase and the maximum specific growth rate.

While various studies have focused on the significance of computational thinking (CT) for the future career paths of individuals in science, technology, engineering, and mathematics (STEM), few studies have focused on computational thinking for non-STEM college students. This study explores the relationship between computational thinking and learning satisfaction for non-STEM-major college students. A conceptual model is proposed to examine the structural relationships among computational thinking, self-efficacy, self-exploration, enjoyment and learning satisfaction in an AppInventor-based liberal education course. Collecting data from 190 undergraduate students from Taiwan and analyzing the data by using partial least squares (PLS) methods, the research framework confirms the six proposed hypotheses. These results show that both computational thinking and enjoyment play significant roles in both self-exploration and digital self-efficacy. Moreover, digital self-efficacy and self-exploration also have a significant positive influence on learning satisfaction. These findings have implications for influencing the learning outcomes of non-STEM-major college students, computational thinking course instructors, and computational thinking relevant policies.

Travel time prediction has been the fundamental brick for developing both Advanced Traffic Management Systems (ATMS) and Advanced Traveler Information Systems (ATIS). The problem of travel time prediction is primarily shaped by the data available for model development and the needs from the perspectives of both travelers and operators. A distance-based Electronic Toll Collection (ETC) system over the freeway system in Taiwan has been fully implemented since December 2013, which provides more comprehensive online data acquisition of freeway traffic conditions, thereby enabling the capability to more reliably predict of travel time over freeway segments. Based on the data from both the ETC system and traditional Vehicle Detectors (VDs), this research proposes a travel time prediction approach whose core technique of data fusion seeks to seamlessly capture the spatio-temporal pattern of freeway traffic flows by matching traffic dynamics revealed from the ETC and VD data. Further, prediction models are constructed thereupon, where the Kalman filter is employed for short-term prediction and the Fourier transform for long-term prediction based on the continuous parameterized modeling of spot travel speed. The proposed approach is implemented as an online deployable system using Java, together with real-world data collected from the freeway in Taiwan, for the numerical experiments. The prediction errors are no greater than 10% in most cases, which illustrates the high accuracy of prediction capability of the model. The encouraging results also highlight the benefits of the pre-processing of data and data fusion in improving data quality and applicability.

Dichloromethane (DCM) is one of the most commonly used solvents in industry. DCM easily accumulates and breaks down slowly; it is recognized as being carcinogenic. This research uses the sol-gel method to synthesize Mesoporous Mobil Catalytic Material Number 41 (MCM-41), Fe-MCM-41 and Pt-MCM-41 catalysts, and discusses the effectiveness of using these self-made catalysts to treat DCM. The qualities of each catalyst are identified using XRPD, BET, and SEM–EDS characteristic analyses. These results are then analyzed using the reaction kinetics theory. Results show that removal efficiency increases with the increase in temperature and concentration, and decreases with the increase in reaction chamber flow rates. Adsorption of DCM using mesoporous metal catalysts conforms to the Langmuir isotherm adsorption model. It was found that the best correlation results were observed for a Pt-MCM-41 catalyst.

Mercury is a physiological toxin released by spent fluorescent lamps (SFLs) and is considered a serious pollutant. As the world’s largest producer of fluorescent lamps, China suffers from SFL pollution because of inefficient recycling and management of SFLs. Drawing upon the most successful practices worldwide, this paper suggests the recycling of SFLs on the basis of the extended producer responsibility (EPR) system in China. Manufacturers and importers are the main parties responsible for the take-back, recycling, and disposal of SFLs in the EPR system. In view of the situation in China and to address the objectives of the EPR system, this paper recommends the implementation of a third-party take-back mode for small- and medium-scale enterprises and of a take-back mode for large enterprises to be carried out by original equipment manufacturers. This paper suggests an extended responsibility fund to finance and support the SFL recycling system and discusses in detail the different recycling network systems and fund flows of the two take-back modes. By conducting a case study, the authors determine that the subsidy rate for SFLs that a recycling company can obtain from the extended responsibility fund for recycling and disposing of lamps can be set at $1.35/kg. The authors also predict the levy level that fluorescent lamp manufacturers must submit.Implications:For policymakers, a proper and effective way to manage and recycle spent fluorescent lamps (SFLs) is necessary. The recommended system and the predicted number values of the subsidy rate and levy level can be the basis in practice. For people, the proper management measures will reduce exposure from SFLs effectively, especially the risk of exposure to mercury. For society, the measures can help increase resource utilization rate. For manufacturers, an effective extended responsibility fund will motivate them to improve processing technique and green design.

Mesoporous MCM-41 was synthesized using cetyltrimethyl ammonium bromide (CTAB) as a cationic surfactant and spent quartz sand as the silica source. Modification of the mesoporous structure to create an absorbent was then completed using 3-aminopropyltrimethoxysilane. Amine-Quartz-MCM (The A-Q-MCM) adsorbents were then characterized by N2adsorption/desorption, elemental analysis (EA), X-ray fluorescence (XRF), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), as well as the carbon dioxide (CO2) adsorption/desorption performance. In this study, spent quartz sand was utilized to synthesize Quartz-MCM (Q-MCM) and the amine functionalized material, A-Q-MCM, which exhibited a higher uptake of CO2at room temperature compared with the nongrafted material. The results showed that Q-MCM is similar to MCM-41 synthesized using commercial methods. The surface area, pore volume, and pore diameter were found to be as high as 1028 m2/g, 0.907 cm3/g, and 3.04 nm, respectively. Under the condition of CO2concentration of 5000 ppm, retention time of 50 cc/min, and the dosage of 1 g/cm3, the mean adsorption capacity of CO2onto A-Q-MCM was about 89 mg/g, and the nitrogen content of A-Q-MCM was 2.74%. The adsorption equilibrium was modeled well using a Freundlich isotherm.Implications:In this study, spent quartz sand was utilized to synthesize Q-MCM. The amine functionalized material exhibited a higher uptake of CO2at room temperature compared with the nongrafted material. The results showed that Q-MCM is similar to MCM-41 synthesized using commercial methods. The adsorption equilibrium was modeled well using a Freundlich isotherm.

In this study, polyvinyl alcohol (PVA) and titania (TiO2) Degussa P-25 were mixed to generate TiO2nonwoven filters using electrospinning. The wires of titanium dioxide and the nonwoven binding titania nanofibers were formed using 14 kV voltage and a distance of 15 cm. A single-factor experimental method was used to investigate the effects of parameters such as initial concentration, retention time, and light source on acetone removal by nonwoven binding titania nanofibers. Furthermore, the effects of parameters such as gas pressure, particle size, initial concentration, and retention time on the removal of particulates were also assessed. The results showed that the degradation efficiency increased with decreasing initial concentrations and increasing retention time. The best operational conditions during this study for the removal of acetone using the TiO2nonwoven filters were a retention time of 100 sec, initial acetone concentration of 250 ppm, and ultraviolet (UV) light source of 254 nm. Under those conditions, 99% acetone removal efficiency was obtained. In addition, 90% particulate matter removal efficiency was reached when the particulate size was greater than 200 nm and the reaction time was longer than 5 minutes. The prepared TiO2/nanofiber has good performance for volatile organic compounds (VOCs) and particulate removal at the same time.Implications: In this study, polyvinyl alcohol (PVA) and titania (TiO2) Degussa P-25 were mixed to generate TiO2nonwoven filters using electrospinning. The results showed that the optimum operating conditions for the removal of acetone using the TiO2nonwoven filters were a retention time of 100 sec, initial acetone concentration of 250 ppm, and UV light source of 254 nm. Under those conditions, 99% acetone removal efficiency was obtained.

Graphene-TiO2was obtained by reduction of graphite oxide by the hydrothermal method. Using photocatalytic activity to reduce carbon dioxide to methanol and formic acid was investigated in this study. The results show that the graphene loading affects the absorption of light in the visible light region. A larger surface area can also improve the catalytic activity. The largest yield of methanol and formic acid, under light of 365 nm, can reach 160 and 150 μmol g−1, respectively, with 8.5% graphene loading. An increase in graphene loading can enhance photocatalytic performance, but too much will also decrease the reduction efficiency by shielding the light from reaching the catalytic surface. The effect of pH was also investigated. The mechanism of the reaction was also discussed in this study.Implications: Graphene-TiO2hybrids were prepared by the hydrothermal method. Surface area and visible light adsorption increased with the graphene loading. Increased graphene loading improved the methanol and formic acid production. Too much graphene loading will decrease the reduction efficiency. The effect of pH shows that the HCO3−species prefers the formation of formic acid. The mechanism of the reaction was also discussed in this study.

Since Taiwan lacks self-produced energy, and is 98 percent reliant on imports for its primary energy. Increasing energy efficiency and energy savings are an essential part of Taiwan’s energy policy. This work summarized the energy saving potential of the Taiwanese textile industry from the on-line Energy Declare System in 2008. It was found that the total potential energy savings was thus 64,034 KL of crude oil equivalent (KLOE). The energy saving potential identified was 94,614MWh of electricity, 24,536 kiloliters of fuel oil, and 23,722 tons of fuel coal. It represented a reduction of 192,353 tons in carbon dioxide emissions.

When ethylene/nitrogen (C2H4/N2) mixtures are used to deposit carbon films by thermal chemical vapor deposition (CVD), effects of C2H4/(C2H4 + N2) ratios on the deposition rate and microstructures of carbon films are investigated. Experimental results reveal that the deposition rate of carbon films increases with the C2H4/(C2H4 + N2) ratio, and also, raises with the residence time, deposition temperature, and working pressure. The kinetics of this thermal CVD process is discussed. The deposition rate of carbon films is proportional to the C2H4/(C2H4 + N2) ratio with a power of second order, which is resulted from the adsorption of remaining precursor gases C2H4 on the silica glass plate substrate. Few nitrogen and hydrogen atoms are incorporated into carbon films. As the partial pressure of C2H4 is smaller than a threshold pressure or the residence time is shorter than a threshold residence time, no film is formed. The activation energy (= 448 kJ/mole) of carbon deposition is related to the activation energy of C2H4 dissociation. The degree of ordering and nano-crystallite size of carbon films decrease with increasing the C2H4/(C2H4 + N2) ratio, while the sp3 carbon atoms of carbon films increase. Finally, the results of thermal CVD carbon deposition using C2H4 are compared with those using methane and acetylene.

This study evaluated the performance of a photoreactor packed with TiO2/Quartz and ZrO2/Quartz, ZnO/Quartz, initiated by UV irradiation. The experimental results showed that the concentration of VOCs increased and the degration efficiency decreased at the same residence time. Additionally, as the residence time increased, degration efficiency increased. According to the Langmuir-Hinshelwood Model’s predicted results, the reaction rate constant (kc) was 50.1, 7.2, and 3.0 ppm min-1 for TiO2/Quartz, ZrO2/Quartz and ZnO/Quartz, respectively. In contrast, the adsorption equilibrium constant (K) was 10.0, 21.9, and 2.4 ppm-1 with the previous catalyst, individually.

A new method of Differential Mobility Analyzer (DMA) operation using a Fast Scanning Differential Mobility Analyzer (FDMA) nanometer particle sizer has been implemented. By optimizing the flow and voltage ramps, improvements can be made in the FDMA's measurement size range, counting statistics and resolution. In this study, an electrostatic classifier was used to generate mono-dispersed particles of different sizes to calibrate the delay time of the FDMA. The aerosol from incense combustion could be measured directly by FDMA although the particulate concentration was as high as 1,011 particles cm-3. The resolution of the FDMA was 3 nm and better than the SMPS (10nm).

The long tunnel is a fixed, semi-closed environment where excessive concentrations of air pollutants are easily accumulated. This can potentially have a serious affect on drivers’ health, especially when operating vehicles in the long tunnel for a lengthy period of time. Therefore, studies on pollutant emission characteristics and influential factors of emission in the tunnel are important. In this study, several sampling sites were arranged in the 12.9 km long Hsueh-shan Tunnel, to help understand the piston effect of pollutant emission characteristics and spatial concentration distribution. In order to understand the influential factor of air quality in the long tunnel, several tests were run during a closed period, an open period, a non-rush hour period, and a rush hour period. The results showed that during the closed period, the CO, SO2, NOx, and PM10concentrations in the Hsueh-shan Tunnel were in the range of: 0.58–0.64 ppm, 0.94–1.08 ppb, 6.33–7.11 ppb, and 45.4–54.3 µg/m3, respectively. In contrast, during the open period, the CO, SO2, NOx,and PM10concentrations reached 12–39 ppm, 20–48 ppb, 1.2–3.1 ppm, and 75–177 µg/m3, respectively. In the Hsueh-shan Tunnel, the number of vehicles at rush hour was about 1400 per hour, three times higher than during non-rush hour. The piston effect is very obvious since pollutant concentrations are elevated with increasing distance from the inlet. This study found that the pollutant concentration near the outlet can be three times higher than that near the inlet.

ABSTRACTVolatile organic compounds (VOCs) emitted from surface coatings have caused growing public concern for air quality. Even the low-emitted VOC impact from water-based paints on indoor air quality in urban areas has caused concern. This paper presents experimental data using a mathematical model to simulate dynamic VOC emissions from water-based paints that is based on mass transfer and molecular diffusion theories. A series of field-analogous experiments were carried out to continuously measure the VOCs emitted from two typical water-based paints using a gas chromatography–flame-ionization detector monitor in an artificial wind tunnel system. In the study cases, the mass flux of VOCs emitted from the water-based paints was up to 50 μg/m2sec. It was found that the time needed to completely emit VOCs from water-based paints is just hundreds of seconds. However, the order of magnitude of the VOC emission rate from water-based paints is not lower than that from some dry building materials and solvent-based paints. The experimental data were used to produce a useful semiempirical correlation to estimate the VOC emission rates for water-based paints. This correlation is valid under appropriate conditions as suggested by this work with a statistical deviation of ±7.6%. With this correlation, it seems feasible to predict the dynamic emission rates for VOCs during a painting process. This correlation is applicable for assessing the hazardous air pollutant impact on indoor air quality or for environmental risk assessment. Associated with the dynamic VOC emission characterization, the air-exchange rate effect on the VOC emission rates is also discussed.IMPLICATIONSThis paper presents experimental data using a mathematical model to simulate dynamic VOC emissions from water-based paints that is based on mass transfer and molecular diffusion theories. A semiempirical correlation is suggested to estimate the VOC emission rates for water-based paints. With this correlation, it is feasible to interpret and predict the dynamic emission rates for VOCs during a painting process. The results obtained in this work will be useful in evaluating the indoor air quality impact by primary VOCs or hazardous air pollutants emitted from water-based paints.

A short-term, real-time system was developed to support traffic management in Beijing. The requirements of a large amount of data and unstable traffic flow are the biggest challenges to such a system. The models and software framework thus should be effective enough to face these problems. The core of such a system is the short-term traffic flow forecast model. Rapid urbanization and transportation development in Beijing have led to traffic flow patterns with some unstable characteristics. The short-term forecast model for an online system thus was designed with the fast-paced trend in mind. The model considers historical data, real-time data, and space data, and it can be updated online. Thus a combined model was developed with three submodels: discrete Fourier transform model, autoregressive model, and neighborhood regression model. Weights of each submodel were based on forecast error. Both the historical forecast error and real-time forecast error were considered. The system was built on a browser-server structure to support combined forecast models. The framework, modules, and interface of this system are introduced in this paper.

AbstractParticles emitted from gravel processing sites are one contributor to worsening air quality in Taiwan. Major pollution sources at gravel processing sites include gravel and sand piles, unpaved roads, material crushers, and bare ground. This study analyzed fugitive dust emission characteristics at each pollution source using several types of particle samplers, including total suspended particulates (TSP), suspended particulate (PM10), fine suspended particulate (PM2.5), particulate sizer, and dust-fall collectors. Furthermore, silt content and moisture in the gravel were measured to develop particulate emission factors. The results showed that TSP (<100 µm) concentrations at the boundary of gravel sites ranged from 280 to 1290 µg/m3, which clearly exceeds the Taiwan hourly air quality standard of 500 µg/m3. Moreover, PM10concentrations, ranging from 135 to 550 µg/m3, were also above the daily air quality standard of 125 µg/m3and approximately 1.2 and 1.5 times the PM2.5concentrations, ranging from 105 to 470 µg/m3. The size distribution analysis reveals that mass mean diameter and geometric standard deviation ranged from 3.2 to 5.7 µm and from 2.82 to 5.51, respectively. In this study, spraying surfactant was the most effective control strategy to abate windblown dust from unpaved roads, having a control efficiency of approximately 93%, which is significantly higher than using paved road strategies with a control efficiency of approximately 45%. For paved roads, wet suppression provided the best dust control efficiencies ranging from 50 to 83%. Re-vegetation of disturbed ground had dust control efficiencies ranging from 48 to 64%.

A short-term, real-time system was developed to support traffic management in Beijing. The requirements of a large amount of data and unstable traffic flow are the biggest challenges to such a system. The models and software framework thus should be effective enough to face these problems. The core of such a system is the short-term traffic flow forecast model. Rapid urbanization and transportation development in Beijing have led to traffic flow patterns with some unstable characteristics. The short-term forecast model for an online system thus was designed with the fast-paced trend in mind. The model considers historical data, real-time data, and space data, and it can be updated online. Thus a combined model was developed with three submodels: discrete Fourier transform model, autoregressive model, and neighborhood regression model. Weights of each submodel were based on forecast error. Both the historical forecast error and real-time forecast error were considered. The system was built on a browser–server structure to support combined forecast models. The framework, modules, and interface of this system are introduced in this paper.

In this study a kaolinite-Ag catalyst and a kaolinite-Zn catalyst are prepared for use in photocatalysis which uses irradiation by sodium light to damage the cell structures of bacteria in water for disinfection. The experimental results indicated that kaolinite-Ag catalyst and kaolinite-Zn catalyst have the best disinfection efficiency when 0.06 wt% are added and reached 90% and 85% disinfection efficiency when they were exposed to sodium light for 200 minutes. Among the individual catalysts, kaolinite-Zn catalyst releases more intermediates at the latter stage of photocatalysis (proved by the concentration level of total organic carbon, TOC); it is easy for the intermediates to compete with the catalyst. The activation rate of target objects on the surface of the Zn catalyst, thus, slows down and results in slower spread of disinfection in the latter part of the reaction curve.

AbstractVolatile organic compounds (VOCs) are the cause of indoor air pollution and are readily emitted from furniture and cleaning agents. In Taiwan, the concentrations of indoor VOCs range roughly from 1 to 10 ppm. It is important to effectively reduce indoor VOC emissions and establish the implementation of long-term, low-cost, controlled techniques such as those found in the ultraviolet/titanium dioxide (UV/TiO2) control systems. This study evaluates the performance of a photoreactor activated by visible irradiation and packed with TiO2/quartz or TiO2/mobile catalytic material number 41 (MCM-41). The photocatalysts tested include commercial TiO2(Degussa P-25) and synthesized TiO2with a modified sol-gel process. The UV light had a wavelength of 365 nm and contained an 8-W, low-pressure mercury lamp. Reactants and products were analyzed quantitatively by using gas chromatography with a flame-ionization detector. It is important to understand the influence of such operational parameters, such as concentration of pollutant, temperature, and retention time of processing. The indoor concentrations of VOCs varied from 2 to 10 ppm. Additionally, the temperatures ranged from 15 to 35 °C and the retention time tested from 2 to 8.2 sec. The results show that quartz with TiO2had a better photoreductive efficiency than quartz with MCM-41. The toluene degradation efficiency of 77.4% with UV/TiO2/quartz was larger than that of 54.4% with the UV/TiO2/MCM-41 system under 10-min reaction time. The degradation efficiency of the UV/TiO2system decreased with the increasing concentrations of indoor VOCs. The toluene degradation efficiency at 2 ppm was approximately 5 times greater than that at 10 ppm. The photoreduction rate of the VOCs was also evaluated with the Langmuir– Hinshewood model and was shown to be pseudo-first-order kinetics.

The study demonstrates a novel attempt to use an aerobic biofiltration system containing entrapped mixed microbial cells (EMMC) for removal of hydrogen sulfide dominant waste gases. In the study, heterotrophic microflora-immobilized cellulose was packed into an EMMC reactor to degrade hydrogen sulfide. Effects of hydrogen sulfide concentrations for continuous operation at various flow rates indicated that hydrogen sulfide removal efficiency is higher than 90% at inlet loadings below 4.31 mg-S/min for retention time of 5.3 minutes. This EMMC biofiltration system also showed high tolerance to fluctuations in flow rates while maintaining stable removal performance. The predicted kinetic constant k and maximum mass loading are 0.018 s-1 and 8.64 mg-S/min, respectively. Adaptability tests in response to gradual shifts up and down of inlet hydrogen sulfide loading indicated that the EMMC microbial communities were well-acclimated to maintain long-term operation stability for continuous treatment.

AbstractThis study attempts to assess the effectiveness of control strategies for reducing volatile organic compound (VOC) emission from the polyvinyl chloride (PVC) wallpaper production industry. In Taiwan, methyl ethyl ketone, TOL, and cyclohexanone have comprised the major content of solvents, accounting for ∼113,000 t/yr to avoid excessive viscosity of plasticizer dioctyl phthalate (DOP) and to increase facility in working. Emissions of these VOCs from solvents have caused serious odor and worse air quality problems. In this study, 80 stacks in five factories were tested to evaluate emission characteristics at each VOC source. After examining the VOC concentrations in the flue gases and contents, the VOC emission rate before treatment and from fugitive sources was 93,000 and 800 t/yr, respectively. In this study, the semiwet electrostatic precipitator is recommended for use as cost-effective control equipment.

Particles emitted from gravel processing sites have severely worsened ambient air quality. This study analyzed the fugitive dust emission characteristics at selected pollution sources using several kinds of particle samplers, including TSP, PM10, PM2.5, and dry deposition plate. It is the first attempt to modify emission factors of AP-42 with a systematical study, utilizing domestic information under dimensionless analysis at the gravel processing sites. Results showed that TSP concentrations at the boundary of gravel sites ranged from 280 to 1,290 µg/m3. Moreover, PM10 concentrations ranged from 135 to 550 µg/m3which were 1.2–1.5 times PM2.5concentrations, which ranged from 105 to 470 µg/m3. Emission of unpaved roads accounted for about 45–55% of the total emission at the gravel processing sites. The silt and moisture content of gravel/sand/dust affected the emission rate of each emission source and ranged from 0.1 to 8.3 % for silt and from 0.6 to 14 % for moisture. After statistical analysis using the least square method, the domestic emission factors of four main emission sources were developed. Furthermore, the size coefficient of emission factors for TSP, PM10, and PM2.5emission rate estimation equation were also determined in this study.

AbstractFugitive dust emission from limestone extraction areas is a significant pollution source. The cracking operation in limestone extraction areas easily causes high total suspended particulate (TSP) concentrations in the atmosphere, occasionally exceeding the 1-hr national emission standard of Taiwan (500 μg/m3). The concentration and size distribution were measured at different distances (0.05–15 km) in the extraction areas. The highest hourly concentrations of TSP, PM10(suspended particulate matter [PM] smaller than 10 μm), and PM2.5(suspended PM smaller than 2.5 μm) are 1111, 825, and 236 μg/m3, respectively, during the cracking process. Measurement results obtained from the Micro-Orifice Uniform Deposit Impactor indicated that the mass median aerodynamic diameter is ∼0.7 μm, with the geometric standard deviation exceeding 7. In addition, the emission factors are 0.143 and 0.211 kg/t for both vertical well and stair extraction operations, respectively. Experimental results demonstrate that the corresponding TSP control efficiencies for spraying water, planting grass, setting short walls, paving gravel roads, and establishing vertical well transportation are ∼55, 50, 44, 22, and 30%, respectively. Furthermore, the PM10control efficiencies are ∼45, 41, 54, 35, and 30%, respectively, whereas the PM2.5control efficiencies are roughly 23, 31, 15, 11, and 10%, individually.

ABSTRACTAssembly planning attempts to arrange product assembly sequences on the basis of the input of product description, similar assembly plans and assembly constraints. When considering the assembly planning, the relationships between assembled components can act as important information for assembly planning. The engineer will plan the assembly sequence to consider the related constraint factors. These constraint factors include assembly time, cost, machine idle time…etc. Combining optimization is the problem which the designers must always face in the design refinement process. This problem is to search the optimal solution between the design variables which determine the better product layout. Because this issue is difficulty be solved to use traditional optimizing technique like the linear programming. In this project, we want to use the method of Simulated Annealing to solve combining optimization question. These results will handle the design refinement process and will expand the connector-based product model.

Deriving a precise kinematic model to describe a motorcycle's behavior after impact is a prerequisite for developing a fact-analytical tool for motorcycle accidents. Therefore, this paper successfully derives a high-degrees-of-freedom model. Twenty-four time-response illustrations of simulation results demonstrate the dynamic behavior of the proposed model. A surface diagram is revealed while investigating the vehicle tracking. The twenty-four illustrations include motion, velocity and acceleration with respect to longitudinal, lateral, vertical, pitching, yawing, vehicle rolling, rider rolling, and steering variations. The model proposed herein can be effectively used to preliminarily analyze the tendency toward stability or toward rolling of a motorcycle after a collision.

An oversaturated signalized network needs a dynamic control operation to alleviate traffic congestion. This study presents such a dynamic control with respect to a series of synchronous cycle operations. The adopted model employs the bang-bang like control model for oversaturated intersections mixed with the TRANSYT-7F for undersaturated intersections in the operative algorithm. A mimic network demonstrates the usefulness of the proposed method, revealing that the proposed method is more efficient than pure TRANSYT-7F control

Ramp metering control plays an important role in modem freeway traffic management, particularly during heavy traffic. Based on Payne's continuum traffic stream model, this study presents a nonlinear-integrated-responsive and closed-loop ramp metering control model. Simulation results confirm that the proposed model is robust and efficient for freeway traffic control and, in doing so, maintains freeway operation at a high level of performance. With such control, freeway traffic can eliminate congestion.

In order to effectively control air quality in a plant, the Volatile Organic Compounds (VOCs) emission model was developed to study the effects of influential factors on emission rate. The emission rates of MEK(methyl ethyl ketone), TOL(toluene, ANONE(cyclohexanone) were about in the range of 16.1 × 103 to 101.0 × 103 mg/m2/hr/(g-MEK), 14.3 × 103 to 88.1 × 103 mg/m2/hr/(g-TOL), 5.0 × 103 to 43.8 × 103 mg/m2/hr/(g-ANONE) respectively for the cases of using solvents and plasticizer only. Furthermore, the mass transfer coefficients of MEK, TOL, ANONE, derived from VOCs emission model, were about 0.00246m/sec, 0.00230m/sec, 0.00230m/sec, 0.00218m/sec without PVC powder respectively. However, adding with PVC powder, the emission rate and mass transfer coefficients of MEK, TOL, ANONE are lowered by a factor of 0.66 compared to originals.

In order to set up a vehicle lateral controller for steering automation under the project ADVANCE-F, the frequency-shaped linear quadratic control theory is utilised to design the system for meeting requirements involved in tracking precision, robustness and ride quality by properly choosing the weighting factors. The final controller is composed of a full state feedback regulator with an observer. The simulation results reveal that the controller performs satisfactorily under a variety of situations including wind gust disturbance, transition curve and man-machine switching in a wide speed range from 0 kph to 120 kph.

From the perspective of sprung vehicle dynamics, current highway design criteria are somewhat inadequate for fulfilling broad requirements of automated highway systems and automatic control vehicles. Therefore, in this study, we present a split layout of pavement friction, designed to counterbalance an insufficient superelevation and overcome unpredictable rolling instability. The proposed layout provides different friction pavements between a lane's left and right sides in a curve stretcher along a highway. Such a layout causes vehicles to be more stable in dynamic. In addition, no deficiency arises in setting superelevations, of which, the inclined cross-sections potentially cause side slipping under poor weather conditions. The optimal friction difference values are also illustrated in terms of the radius with respect to AASHTO's criteria. Finally, some implementation issues are also addressed.

A cDNA encoding the banana 1‐aminocyclopropane‐l‐carboxylate (ACC) oxidase has previously been isolated from a eDNA library that was constructed by extracting poly(A)+ RNA from peels of ripening banana. This cDNA, designated as pMAO2, has 1,199 bp and contains an open reading frame of 318 amino acids. In order to identify ripening‐related promoters of the banana ACC oxidase gene, pMAO2 was used as a probe to screen a banana genomic library constructed in the λEMBL3 vector. The banana ACC oxidase MA02 gene has four exons and three introns, with all of the boundaries between these introns and exons sharing a consensus dinucleotide sequence of GT‐AG. The expression of MA02 gene in banana begins after the onset of ripening (stage 2) and continues into later stages of the ripening process. The accumulation of MAO2 mRNA can be induced by 1 μl/l exogenous ethylene, and it reached steady state level when 100 μl/1 exogenous ethylene was present.

VOC(Volatile organic compound) emission rate was modelled in this study. The effects of the different environmental factors and the additives upon the emission rates were also determined. The study was conducted in a test chamber and in the field for determination of the emission rate of methyl ethyl ketone (MEK). Additionally, the theory of mass transfer was used to derive an MEK emission model with three variables (temperature, humidity, ventilation rate) and five coefficients (T1, R1, KB, ACHstd and Cstd); these were determined by the results of emission rate in a test chamber. The emission rate of MEK ranged from 16.1 × 103 to 101.0 × 103 mg/m2/hr/(g-MEK) for those cases which used solvents and plasticizer, and from 5.6×103 to 58.1×103 mg/m2/hr/(g-MEK) when PVC powder was added. Additionally, the MEK emission rates increased with an increase in temperature, humidity, and ventilation rate. The mass transfer coefficients of MEK determined from the VOC emission model were approximately 0.00246 m/sec for those cases which used solvents and plasticizer, and decreased by a factor of 0.67 to 0.00164 m/sec for those cases which used solvents, plasticizer and PVC powder.

ABSTRACTFrom the perspective of sprung vehicle dynamics, the design criteria of superelevation or radius is unsatisfactory for broad requirements. Superelevation design has many limitations. Therefore, in this study, we describe a split layout of pavement friction, designed to counterbalance an insufficiency of superelevation. The layout is to provide different friction pavements between the left and the right sides of a lane in curves. Such a layout would cause vehicles to be more stable, in addition to providing passengers with more comfort. There is no deficiency of placing superelevations, of which the inclined cross-sections possibly cause side slipping in bad weather conditions. Also, the ideal values of friction difference for high design speeds versus various radii are illustrated. How to implement a split friction pavement is also introduced accompanied by an analysis of the selection of materials or aggregates. Finally, a special consideration regarding safety for constructing such a pavement is mentioned.

SrTiO3, Bi2S3, and SrTiO3/Bi2S3heterojunction were prepared for efficient photocatalytic hydrogen production. SrTiO3/Bi2S3heterojunction was prepared by different weight percentages of Bi2S3(1, 3, 5, and 7%) with SrTiO3. SrTiO3and Bi2S3are exhibited in cubic and orthorhombic crystal structures, respectively. The morphologies of SrTiO3and Bi2S3have existed as nanocubic and bar-like structures, respectively. Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) results further confirmed the formation of SrTiO3/Bi2S3heterojunction. The photoluminescence (PL) and electrochemical impedance spectroscopy (EIS) results indicated that the SrTiO3/Bi2S3heterojunction reduces the rate of photogenerated electron–hole pair recombination and electron-transfer resistance than pure SrTiO3and Bi2S3. The formation of SrTiO3/Bi2S3heterojunction effectively separates the photogenerated charge carriers, which enhances the photocatalytic hydrogen production under UV light. The SrTiO3/Bi2S3heterojunction shows superior photocatalytic hydrogen production than bare SrTiO3and Bi2S3due to the synergistic effect. The photocatalytic hydrogen production of SrTiO3/Bi2S3(5%) gives 7.7 mmol g–1within 180 min under UV irradiation.

We have investigated glucose-6-phosphate dehydrogenase (G6PD) deficiency in 220 unrelated aboriginal male subjects who belong to three different tribes (Saisiat, Ami, and Yami) in Taiwan. Our results show that the G6PD deficiency rates for Saisiat, Ami, and Yami people are 9.0% (6/67), 6.1% (6/99), and 0% (0/54), respectively. Among these deficiency cases, 4 of 6 (66.7%) Saisiat subjects have the 493 A?G mutation and one carries the 1376 G?T mutation, whereas, in Ami subjects, we found that four of six (66.7%) affected males have the 592 C?T mutation and one carries the 493 A?G mutation. These results contrast with our previous findings for Taiwan Chinese, in whom the 1376 G?T mutation is the major mutant allele and accounts for 52.3% of the deficiency cases. This is the first report of G6PD deficiency characterized at the DNA level in Taiwan aboriginal populations.