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This research investigated the hydrogen production and energy conversion from automobile shredder residues (ASRs) and paper mill sludge (PMS) co-gasified in a full-scale fluidized bed gasification plant. The results obtained from full-scale tests provided important information on the feasible assessment of ASRs-to-energy and the selection of alternative technologies for ASRs. Based on the analysis results of produced gas composition, H 2 , CO, and CH 4 composition produced from paper-mill sludge gasified were 4.17%–6.01%, 3.08%–4.32%, 1.71%–2.4%, respectively. Another C 2 gas composition ranged from 2.9% to 3.59%. The heating value of produced gas ranged between 1.64 MJ/Nm3 and 2.18 MJ/Nm3. In the case of 10% ASR addition, the heating value of produced gas was slightly increased to 1.84 MJ/Nm3-2.34 MJ/Nm3. The dioxin emission concentration of flue gas was approximately 0.064 ng I-TEQ/Nm3. It can comply with Taiwan regulation thresholds. The dioxin leaching concentrations of residues derived from gasification were also in compliance with regulation limits by the TCLP test. Meanwhile, in the case of 10% ASRs addition, the dioxin equivalence concentration of gasified residue was nearly 0.002 ng I-TEQ/Nm3. It was far below the current regulation standard limit. In summary, the results of this research have proved the performance of ASRs-to-energy by co-gasified with paper mill sludge using a full-scale gasification plant. The results obtained from this research also provided the information for selecting ASRs alternative technologies and operating full-scale gasifiers in the future. [Display omitted] • This study has confirmed the feasibility of co-gasification of calcium-rich PMS and chlorine-rich ASRs. • Adding 5%–15% of ASRs can maintain the regular operation of the full-scale commercial gasifier. • The synthesis gas has a composition of 4.91 vol% H 2 and 2.06 vol% CO, with a LHV of 1.93 MJ/Nm3. • The HCl emission could comply with regulation thresholds in co-gasification. • Dioxin reformation reduced significantly in co-gasification of PMS and ASRs. [ABSTRACT FROM AUTHOR]

• Significant ionospheric disturbances during the 2021 Typhoon Chanthu were observed by GPS and GLONASS. • The ionospheric disturbances following the Typhoon are accompanied and propagated with the "N"-type wave. • The propagation velocity and center frequency of ionospheric disturbances are within the range of gravity waves. Severe typhoons often result in substantial economic and human losses. Therefore, near-real-time monitoring and forecasting of severe typhoons have a significant importance. In this paper, characteristics of ionospheric disturbances during the 2021 Typhoon Chanthu are estimated and investigated from GPS and GLONASS measurements. We calculate high-precision de-trended and filtered ionospheric vertical total electron content (VTEC) data based on GPS and GLONASS data from intensive Global Navigation Satellite System (GNSS) observations at 30-second intervals in Taiwan. Based on the VTEC values, we analyze the characteristics of ionospheric disturbances caused by Typhoon Chanthu, such as the time of appearance of ionospheric disturbances, changes in the magnitude of these disturbances, alterations in two-dimensional disturbances, fluctuations in the speed of disturbance propagation, and shifts in the frequency spectrum. The results reveal that both GPS-TEC and GLONASS-TEC exhibit noticeable disturbances during the specified timeframe. These disturbances are accompanied by the occurrence of "N"-type anomalies in TEC. Notably, at the occurrence of the disturbance, the elevation angle of GPS PRN32 and GLONASS PRN1 satellites is approximately 50°-55°, and their respective distances from the typhoon eye are roughly 350 km and 150 km. The propagation velocity and center frequency of the ionospheric disturbances are located in the range of gravity waves. Specifically, the disturbances propagation speeds of GPS PRN32 and GLONASS PRN1 are approximately 129.36 m/s and 128.33 m/s, respectively, while the center frequencies are about 1.17 mHz and 1.43 mHz. The ionospheric perturbations observed by GPS and GLONASS exhibit certain similarities, which provide valuable insights into the relationship between typhoons and ionospheric disturbances. [ABSTRACT FROM AUTHOR]

• IoT sensors and Signal Detection Theory improve flood modeling accuracy. • IoT flood sensors uniquely identify zero flooding situations. • Optimal spatial scale varies across regions for accurate flood classification. • 450 m is the optimal spatial scale for reliably validating the flood simulation. • Ensemble-based flood verification enhances validation robustness. Inundation mapping by flood simulation is subject to uncertainties which spatial accuracy assessment could not be processed as normal mapping does. This paper presents a comprehensive study on the spatial accuracy of flood verification using Internet of Things (IoT) sensors in several flood-prone regions in Taiwan, including Changhua, Yunlin, Chiayi, Tainan, Kaohsiung, and Pingtung, during three storm events in 2021. The study adopts Signal Detection Theory (SDT) and proposes an ensemble-based approach that combines multiple evaluation metrics to enhance the accuracy and reliability of flood verification in these regions. The study examines the inundation availabilities between flood observation from IoT sensors and flood simulation. A range of spatial scales varies from 100 m to 1000 m and also administrative divisions are considered including neighborhood-level and village-level scales. The results show that increasing the spatial scale generally leads to higher True Positives, indicating improved flood detection, but it also results in increased False Positives, indicating more misclassification of non-flooded points. The findings reveal that the optimal spatial scale for all cities/counties is 450 m which indicates the averaged spatial accuracy of the flood simulation. However, there is notable variation in the optimal spatial scale across different regions. The ensemble approach demonstrates high consistency in determining the optimal spatial scale, as eight out of ten metrics consistently identify the same value. Additionally, the study compares flood verification across administrative divisions in Taiwan, finding that the village-level spatial scale performs best in Changhua and Yunlin counties, while the neighborhood-level scale is preferred in Tainan, Kaohsiung, and Pingtung. This research provides a valuable framework to estimate inundation mapping accuracy under flood verification using IoT sensors in the specified region of Taiwan and highlights the importance of considering local conditions and administrative divisions in determining the optimal spatial scale. These findings can contribute to the improvement of flood detection and monitoring systems in the area with IoT flood sensors. [ABSTRACT FROM AUTHOR]

One of the least studied eyes of any beetle taxon are those of the scarabaeoid family Passalidae. Some members of this family of around 600 species worldwide are known to have superposition eyes (Aceraius grandis; A. hikidai) while others have apposition eyes (Cylindrocaulus patalis ; Ceracupes yui). In C. yui of nearly 3 cm body length (this paper) the retinal layer is very thin and occupies approximately half of an ommatidium's total length, the latter amounting to 284 and 266 μm in the respective dorsal and ventral eye regions. The two eye regions are almost completely separated by a prominent cuticular canthus, a feature usually associated with the presence of a tracheal tapetum, a clear-zone between dioptric and light-perceiving structures and a regular array of smooth facets. In C. yui the facets are smooth (but not very regular) and a tracheal tapetum and a clear-zone are absent. The rhabdoms, formed by 8–9 retinula cells, are complicated, multilobed structures with widths and lengths of around 15 and 80 μm, respectively. The combination of some superposition and mostly apposition eye features, e.g., extensive corneal exocones, relatively small number of ommatidia, absence of a clear-zone and tracheal bush, suggest an adaptation of this species' eye to the fossorial lifestyle of C. yui , and, thus, a manifestation of the passalid eye's plasticity. • First detailed ultrastructural study of the eye of a passalid from Taiwan. • Description of a scarabaeoid beetle eye in which apposition features dominate. • Eye adaptations to accommodate the species' fossorial lifestyle. • Compromise between adaptations to protect the eye against physical damage and to retain some sensitivity. [ABSTRACT FROM AUTHOR]

An approach involving data on wave-induced sediment transport estimates is essential for managing coastal environments. Numerical models are powerful tools to understand and investigate many processes responsible for longshore sediment transport (LST) in a systematic way, since direct measurement of LST is a difficult task. This paper presents estimates of longshore sediment transport through numerical modeling of wave-induced sediment dispersion patterns in the Formosa Bay, State of Rio de Janeiro - Southeast Brazil. The analysis was conducted using the computational package Coastal Modeling System/SMC-Brazil and mathematical formulations proposed by Cerc (1984). The results suggest average residual solid discharge (Qsr avg) in the order of 131,442.745 m3/yr in northern sector, −151,908.32 m3/yr in central sector, and 71,987.69 m3/yr in southern sector of investigated area. In addition, it is important to highlight that minor variations in the wave incidence angle may cause changes in the longshore sediment drift, promoting the convergence and divergence zones throughout the investigated area. The results presented contribute to the advancement of knowledge on the topic addressed here and will be useful in future engineering projects related to beach nourishment and the management of coastal areas subject to erosion processes. • Data are presented on simulations of wave-induced longshore sediment transport rates in Baia Formosa Bay, southeastern Brazil. • The Coastal Modeling System SMC/Brazil were used. • Results suggest different solid outflow rates for each sector of investigated area. • The model may provide a basis for planning actions and environmental management in coastal zones. [ABSTRACT FROM AUTHOR]

Green energy has become a global development trend, with solar power generation being a critical aspect of this movement. However, the development of solar power generation requires significant land resources, which poses a challenge in Taiwan due to its small area and dense population. Nevertheless, Taiwan possesses ample land resources in the aquaculture industry, with approximately 40,000 ha of aquaculture area. Hence, a new aquaculture model called aquavoltaics can be developed by integrating the aquaculture industry with solar power generation. This paper employs the Cost-Benefit Analysis and Monte-Carlo Method to evaluate the economic feasibility and analyze the risk of whiteleg shrimp culture under six different aquavoltaic configurations. The results demonstrate that all six types of aquavoltaics for whiteleg shrimp culture are economically viable. Furthermore, among the ground-type aquavoltaic systems, the embankment type exhibits the highest profitability and the lowest investment risk. As for facility-type aquavoltaics, the greenhouse type represents the most favorable investment scheme. • Aquavoitaics farming white shrimp has potential for development in Taiwan. • Aquavoitaics facilitates the transformation and upgrading of the aquaculture industry while promoting diversified land development and increasing income sources for farmers. • The initial investment threshold of aquavoltaics is high, the successful transformation could be achieved through government or enterprise investment. [ABSTRACT FROM AUTHOR]

This research studies the characteristics of ocean current meanders from the viewpoint of power generation engineering and the potential of maximizing ocean current power generation capacity by making generator turbines to track the meanders applying a recently proposed Cross-stream Active Mooring concept. The current meanders will hurt capacity factor of marine turbines moored at fixed locations, somewhat like the issue of wind availability for wind farms. The new mooring concept features a hydro sail system that can deploy generator turbines transversely across streams in a marine current. The hydro sail system can further adjust the horizontal position of the turbines, by changing sail angle of attack, to actively track fast streams in an ocean current. This paper first reviews and discusses the characteristics of short-term track variations of the Florida Current and the Kuroshio near Taiwan and then analyzes potential improvement in power generation using measured and simulated current velocity data in the two ocean currents, suggesting a potential increase of 10–40 % power generation achievable by tracking the meanders. Operations of the hydro sail were demonstrated by tests using remote controllable and passive scale models. Control methods are discussed. Approaches to observe, predict and track the meanders are conceptualized. [ABSTRACT FROM AUTHOR]

This research studies the characteristics of ocean current meanders from the viewpoint of power generation engineering and the potential of maximizing ocean current power generation capacity by making generator turbines to track the meanders applying a recently proposed Cross-stream Active Mooring concept. The current meanders will hurt capacity factor of marine turbines moored at fixed locations, somewhat like the issue of wind availability for wind farms. The new mooring concept features a hydro sail system that can deploy generator turbines transversely across streams in a marine current. The hydro sail system can further adjust the horizontal position of the turbines, by changing sail angle of attack, to actively track fast streams in an ocean current. This paper first reviews and discusses the characteristics of short-term track variations of the Florida Current and the Kuroshio near Taiwan and then analyzes potential improvement in power generation using measured and simulated current velocity data in the two ocean currents, suggesting a potential increase of 10–40 % power generation achievable by tracking the meanders. Operations of the hydro sail were demonstrated by tests using remote controllable and passive scale models. Control methods are discussed. Approaches to observe, predict and track the meanders are conceptualized. [ABSTRACT FROM AUTHOR]

Structural integrity analysis for reactor pressure vessel (RPV) nozzles has been a vital issue due to the irradiation embrittlement and especially the discontinuity of geometry in RPV nozzles, which may cause a higher stress concentration and influence the structural integrity of RPV nozzles. For the linear elastic fracture mechanics (LEFM) analysis of the RPV nozzle, a postulated crack with a specific crack depth is presumed to evaluate the stress intensity factors (SIFs) whose crack depth does not grow during LEFM analysis. Thus, this paper would discuss the crack propagation for the postulated crack with a specific crack depth under the different reference temperature of nil-ductility transition (R T N D T ), and the SIFs on the specific crack depth are also calculated. In recent research, the extended finite element method (XFEM) was developed, which is based on the enrichment solution space to simplify the computational fracture mechanics with the crack propagation of various discontinuities, and can be used to evaluate the crack propagation of RPV nozzle with a specific crack depth under R T N D T of −23.89, −10.89, 0.89, 2.69, and 2.89 °C. To investigate the crack propagation and structural integrity of RPV nozzles, the finite element analysis of Taiwan domestic boiling water reactor (BWR) nozzles containing the postulated circular corner crack with depths of one-fourth and one-tenth thickness along the 45° path from the tip of the nozzle corner is engaged. The present result shows that the crack was growing when the R T N D T was 0.89 °C and. In addition, the XFEM calculation of the SIFs for the specific crack depth is similar to the LEFM results. • The RPV nozzles with postulated cracks were established to investigate crack propagation through XFEM. • The differences in RT NDT were used to evaluate the fracture toughness and discuss the crack propagation for RPV nozzles. • The stress intensity factors (SIFs) obtained by XFEM, LEFM, and the ASME BPVC were compared. • The XFEM analysis would overestimate SIFs more than the ASME BPVC and the LEFM. [ABSTRACT FROM AUTHOR]