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From visitors to vitality: How relational populations support regional revitalization in aging urban and rural areas
No full textUrban shrinkage, exacerbated by population aging, is a critical global issue, with particularly severe effects in Asia. This study introduces the concept of the "relational population," highlighting the potential of tourists as long-term contributors to regional revitalization. Unlike traditional tourist roles, this research explores how tourists can foster regional vitality by becoming emotionally invested stakeholders. Focusing on Tamsui, a shrinking urban and rural area, this study aims to transform tourists into a relational population, deepening their connection to Tamsui's cultural heritage. Using structural equation modeling to analyze data from 473 survey responses, the findings underscore the significant influence of place attachment on tourist engagement, emotional cohesion, and co-creation of value. The results suggest a paradigm shift: tourists are evolving from mere economic agents to essential participants in regional revitalization, particularly in addressing demographic challenges.補正完畢US
Do Price Jumps Matter in Volatility Forecasts of US Treasury Futures?
No full textThis study investigates volatility forecasts in the US Treasury futures market and emphasizes the importance of price jumps across various maturities under moderate and sharp interest rate rising scenarios. We assess out-of-sample forecasting performance not only with statistical method but economic method based on a volatility timing strategy. Our findings indicate that models including price jumps specifications exhibit substantial enhancements in both evaluation methods over the entire out-of-sample period, particular for the period of sharp interest rate rising. Our results are robust to nonparametric jump tests used in this study, transaction costs, and portfolio rebalancing method.補正完畢US
Synthesis and characterization of porous HKUST-1 metal organic frameworks for hydrogen storage
No full textHydrogen storage capacity has been investigated on a copper-based metal organic framework named HKUST-1 with fine structural analyses. The crystalline structure of HKUST-1 MOF has been confirmed from the powder X-ray diffraction and the average particle diameter has been found about 15–20 μm identified by FE-SEM. Nitrogen adsorption isotherms show that HKUST-1 MOF has approximately type-I isotherm with a BET specific surface area of 1055 m2g−1. Hydrogen adsorption study shows that this material can store 0.47 wt.% of H2 at 303 K and 35 bar. The existence of Cu (II) in crystalline framework of HKUST-1 MOF has been confirmed by pre-edge XANES spectra. The sharp feature at 8985.8 eV in XANES spectra represents the dipole-allowed electron transition from 1s to 4pxy. In addition, EXAFS spectra indicate that HKUST-1 MOF structure has the Cu–O bond distance of 1.95 Å with a coordination number of 4.2.補正完畢NL
全球水泥產業減碳技術發展現況：碳捕捉與節能技術整合分析
No full text水泥生產過程中的碳排放主要源自原料煅燒過程中碳酸鈣分解(~65%)及燃料燃燒(~35%)。面對這項脫碳(decarbonation)挑戰，當前技術發展主要聚焦於三個關鍵領域：製程效率提升、替代原料應用，以及碳捕捉技術的整合。在製程效率方面，新型預熱器(pre-heater)與分解爐的開發已使得熱能利用效率提升至傳統製程的1.5倍。透過窯爐系統優化與智能控制，目前最新世代乾法窯(dry-process rotary kilns)的熱耗可降至2,900-3,200 kJ/kg熟料(clinker)。熱能回收系統的改良，特別是懸浮預熱器的多級設計，使得餘熱發電效率顯著提升，每噸熟料可額外產生25-30 kWh電力。替代原料與燃料的應用已進入成熟階段。以工業副產品為例，高爐爐渣(blast furnace slag)與飛灰(fly ash)的摻配可使熟料係數降低至65%以下，同時維持水泥強度等級。在替代燃料方面，經過預處理的固體回收燃料(solid recovered fuels, SRF)熱值已可達到18-22 MJ/kg，且窯爐系統改良使得熱替代率(thermal substitution ratio, TSR)突破70%的技術門檻。碳捕捉技術的發展呈現多元化趨勢。目前主流的後燃燒(post-combustion)捕捉技術採用改良型胺基吸收劑，已將能耗需求從早期的4-5 GJ/ton-CO₂降低至2.5-3 GJ/ton-CO₂。純氧燃燒(oxy-fuel combustion)技術則通過提高煙氣中CO₂濃度(> 85%)來降低捕捉成本。以挪威Brevik碳捕捉項目為例，採用優化的胺吸收工藝，實現年捕獲40萬噸CO₂的規模，捕捉效率達90%以上，展現了技術的工業化可行性。台灣過濾與分離學會、紡織產業綜合研究所、國立台灣大學化學工程系補正完畢國際台北市，臺灣TW
Degradation of TCE, PCE, and 1, 2–DCE DNAPLs in contaminated groundwater using polyethylenimine-modified zero-valent iron nanoparticles
No full textRemediation of dense non-aqueous phase liquid (DNAPL), which consists primarily of chlorinated solvents, is considered a top priority in the field of groundwater decontamination. Downward migration of DNAPL can lead to formation of impermeable strata due to low solubility and high density. Remediation is therefore one of the most complex technical challenges faced by environmental engineers. In the present work, remediation of trichloroethylene (TCE), perchloroethene (PCE), and 1,2-dichloroethene (1,2-DCE) DNAPL-contaminated groundwater was studied by a reductive reaction with polyethylenimine (PEI) surface-modified zero-valent iron nanoparticles (PEI–nZVI). Compared with fresh nZVI, PEI–nZVI exhibited smaller spherical particles of 20–80 nm and a greater surface area of 53.4 m2/g. Furthermore, slow desorption of the PEI indicated its potential application as a protective shell layer for efficient delivery of active nZVI to the water/DNAPL interface. Laboratory batch remediation results indicate that both nZVI and PEI–nZVI can remove 99% of TCE, PCE, and 1,2-DCE. The rate of reaction for fresh nZVI was higher in the early stage. Comparatively, PEI–nZVI had a higher removal rate and efficiency after 2 h. The kinetic studies also revealed that the removal rate for 1,2-DCE was greater than that for TCE and PCE. Additionally, X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectroscopy studies indicated that the nZVI and PEI–nZVI have two central Fe atoms coordinated by primarily Fesingle bondO and Fesingle bondFe with bond distances of 1.87 Å and 3.05 Å, respectively. Furthermore, after the reductive reaction, nZVI and PEI–nZVI were oxidized to Fe3O4, and bond distance values for the reacted samples were 1.94 Å and 1.96 Å, respectively.補正完畢NL
Interrogation of 3d Transition Bimetallic Nanocrystal Nucleation and Growth Using In Situ Electron Microscope and Synchrotron X-ray Techniques
No full textUnderstanding the nucleation and growth mechanism of 3d transition bimetallic nanocrystals (NCs) is crucial to developing NCs with tailored nanostructures and properties. However, it remains a significant challenge due to the complexity of 3d bimetallic NCs formation and their sensitivity to oxygen. Here, by combining in situ electron microscopy and synchrotron X-ray techniques, we elucidate the nucleation and growth pathways of Fe–Ni NCs. Interestingly, the formation of Fe–Ni NCs emerges from the assimilation of Fe into Ni clusters together with the reduction of Fe–Ni oxides. Subsequently, these NCs undergo solid-state phase transitions, resulting in two distinct solid solutions, ultimately dominated by γ-Fe3Ni2. Furthermore, we deconvolve the interplays between local coordination and electronic state concerning the growth temperature. We directly visualize the oxidation-state distributions of Fe and Ni at the nanoscale and investigate their changes. This work may reshape and enhance the understanding of nucleation and growth in atomic crystallization.補正完畢US
Dynamic Analysis of Upper- and Lower-Extremity Performance During Take-Offs and Landings in High-Wall Climbing: Effects of a Plyometric and Strength Training Intervention
No full textThis study used a 12-week plyometric and strength training program as an intervention to improve upper- and lower-extremity muscle strength for jumping and landing when climbing high walls. Sixty general non-athlete male college students were openly recruited and divided into an experimental group and a control group. The experimental group underwent a plyometric and strength training program twice a week for 12 weeks (24 sessions). The intervention was divided into three phases, each lasting four weeks, with the training intensity gradually increasing in each phase. A hand grip dynamometer was used to measure grip strength, and a PASCO double-track force plate was used to assess upper-extremity push-up force and lower-extremity take-off and landing strength. The results of the 12-week intervention showed that the experimental group experienced significant increases in grip strength (both hands), hand-ground reaction force, and upper-extremity hang time. Additionally, the time of upper-extremity action on the force plate decreased. Lower-extremity take-off strength improved, as reflected in increased ground reaction force, rate of force development, and passage time. Upon landing, ground reaction force decreased by 3.2%, and cushioning time shortened by 52.7%. This study concludes that plyometric and strength training have promising effects in enhancing upper- and lower-extremity strength, particularly in climbing and landing tasks.補正完畢CH
Insurer green financing for a supply chain under cap-and-trade regulation: a capped call contingent claim analysis
No full textThis paper introduces a contingent claim analysis to examine sustainable insurance practices. It investigates how life insurers participate in sustainable lending by financing borrowing firms committed to environmentally friendly practices for cleaner production. We establish a capped call option model, where the capped function explicitly considers credit risks associated with borrowing firms in a supply chain engaged in the cap-and-trade mechanism regulated by environmental policies. Our findings reveal that tightening the cap within the cap-and-trade system and reducing green loans can enhance insurer’s interest margins. Conversely, an escalation in the green input ratio across the supply chain may reduce these margins for the insurer. However, reducing low-margin insurance offerings could jeopardize the stability of insurance. The insurer faces financial challenges while supporting borrowing firms in their efforts toward carbon reduction and sustainable production. Notably, the substantial impact of climate change fueled by carbon emissions significantly influences the underwriting of life insurance policies related to human health. Policymakers need to navigate these intricacies to establish a careful balance between environmental objectives and the financial stability of sustainable insurance.補正完畢DE
The Effect of the Gender Equity Education Act in 2004 on the Choice of Study Fields for Senior High School Students
No full text《性別平等教育法》鼓勵女學生主修非傳統性別主流的學習領域。本文分析《性平法》對高中生選自然組的影響。使用資料為「台灣教育長期追蹤資料庫」及其後續調查。發現女性樣本中，《性平法》對選自然組、著重自然科學的學習、大學讀理工學門均有正面影響；但男性樣本中，《性平法》對這些變數均無影響。依公私立高中區分，公立高中分析顯示，《性平法》對女生選自然組有正面影響，對男生沒有影響；但在私立高中，《性平法》對男女選自然組均有正面影響。《性平法》對女生選自然組之影響可能與高學歷父親的性平觀念較佳，以及學習場域中，老師偏好女同學程度之上升有關。補正完畢TW
An approximate numerical analysis of rafts and piled rafts foundation
No full textThe load distribution and deformation of rafts and piled rafts were investigated by an analytical and numerical studies. Special attention is given to the improved analytical method (MEGA piles) proposed by considering raft-pile flexibility and soil-pile nonlinearity. The response of raft, a three-dimensional, thin-plate substructure that bears on the soil, is analyzed by flat shell approach by combining a membrane element with a Reissner-Mindlin plate element. An improved analytical method is also developed for the design of piled raft. A series of numerical analyses on piled raft were performed for different head connected conditions, asymmetric geometry of raft, raft flexibility, pile diameters. The proposed method has been verified by comparing the results with other numerical methods and a field case study. Through comparative studies, it is found that the proposed method represents a significant improvement in the prediction of piled raft load sharing and settlement behavior.補正完畢NL