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Pricing optimization for inventory with integrated storage and credit constraints
No full textPrice is a pivotal determinant of market demand, as higher prices typically reduce sales while lower prices stimulate them. Thus, incorporating price-dependent demand into inventory models is both realistic and necessary. In practice, limited storage capacity often forces retailers to rent additional space, motivating the adoption of two-warehouse systems. Trade credit also plays a critical role in supply chain management: suppliers may offer cash discounts or deferred payments to encourage larger orders, while retailers extend credit to customers to boost sales. To reduce default risk, however, retailers usually provide only partial credit. Considering the time value of money, costs and profits are assessed using discounted cash-flow analysis to account for payment delays and inflation. This study develops an integrated supplier–retailer–customer chain model that (1) incorporates price-dependent demand, (2) includes a rented warehouse for limited storage, (3) considers partial trade credit, (4) links two-level trade credit terms to order quantity, and (5) evaluates financial performance on a present-value basis. The model aims to maximize total profit by determining optimal price, replenishment cycle, and order quantity. Numerical and sensitivity analyses confirm that extending supplier credit can lower prices and improve overall profitability, offering useful insights for strategic inventory management.補正完畢CH
A specific role of village doctors in reducing disparities: a quantile regression analysis of end-of-life medical care
No full textBackground
In developing countries, the delivery of medical care to rural residents has been experiencing long-standing challenges and disparities. Since the 1960s, China has established the village doctors’ system to provide preventive and primary care to improve rural residents’ health. Nevertheless, how village doctors affect the medical spending and the end-of-life (EOL) quality for older people in rural China has not received sufficient attention. Family care has long been the mainstream of old age care in rural China, the accessibility to appropriate medical care is hence crucial. Village doctors are the most accessible medical care providers for rural older people. As a result, this study aims to uncover the importance of village doctors in EOL medical care for rural older people in China.
Methods
The analysis is based on the Chinese Longitudinal Healthy Longevity Survey (CLHLS), which has national representativeness and contains information about the oldest old at an average age of 80 in China, with available information from 2002 to 2019. We adopt the quantile regression to illustrate the heterogeneous impacts of village doctors on the EOL medical care spending from the distribution perspective. We then employ the ordered logit model and ordinary least squares regression to estimate the effects of village doctors on rural older people’s EOL life quality measured by the status before dying and the number of bedridden days.
Results
We find that the EOL medical care spending is significantly increased by the presence of village doctors, especially high-quality ones. The disparities in the EOL medical care in rural and urban China are significantly reduced by high-quality village doctors. However, high-quality village doctors are still insufficient to meet the needs of rural older people regarding the high-end EOL medical care. The empirical results suggest that village doctors can significantly improve older people’s quality of life before death in rural China.
Conclusion
Our analysis highlights the importance of village doctors in providing EOL medical care to older people in rural China. It is crucial for governments to improve the village doctors’ system, so that older residents in rural China can obtain high-quality EOL medical care services in their own communities and have a better quality of life before death.補正完畢TW
How students adopt generative artificial intelligence tools: A case study of higher education students
No full textThis study examined higher education students' perceptions of generative AI tools, particularly ChatGPT, and their intention to adopt them for academic use. Using a modified Technology Acceptance Model 2, it focused on perceived benefits, usability, and concerns related to ethics, dependency, and academic integrity, while also considering prior AI experience and technological proficiency as control variables. Data from a survey of 102 students across disciplines were analyzed to assess how factors such as Perceived Usefulness, Ease of Use, Social Influence, Cognitive Behavior, and Risk influenced adoption intentions. The findings offer insights for universities aiming to implement AI tools that support student needs while promoting ethical and responsible use.補正完畢TW
Asymmetric Fluorinated Cyclopenta [2, 1‐b: 3, 4‐b'] Dithiophene‐Based Hole‐Transporting Materials for Perovskite Solar Cell
No full textA series of asymmetric hole-transporting materials (HTMs) based on cyclopenta[2,1-b;3,4-b’]dithiophene cores tethered with p-methoxytriphenylamines donor units with or without incorporated fluorine atoms were rationally designed, synthesized, and employed in perovskite solar cells (PSCs). A comprehensive comparison is conducted encompassing the absorption spectra, electrochemical characteristics, thermal stability, density functional theory (DFT) calculations, hole mobility, and surface morphology, as revealed by scanning electron microscopy (SEM) and atomic force microscopy (AFM), steady-state and time-resolved photoluminescence measurements, water contact angle analyzes, and photovoltaic parameters of the PSCs. The fluorinated HTMs, P-oF and P-mF, demonstrated enhanced hole mobility and more efficient charge extraction at the perovskite/HTM interface compared to their non-fluorinated counterpart. Consequently, PSCs employing P-oF and P-mF achieved power conversion efficiencies (PCEs) of 21.52% and 19.78%, respectively, with negligible hysteresis, outperforming devices based on P-H, which exhibited a PCE of 17.05%. Moreover, the operational stability of the device incorporating P-series as the HTM exceeded that of the PSCs employing the benchmark material of spiro-OMeTAD. The findings presented herein underscore the facile accessibility and potential of asymmetric compounds as alternative HTMs for PSCs. The results provide valuable insights and serve as a reference for the development of optimal HTMs for PSCs.補正完畢TW
Measuring and managing urban quietness: refining the quietness suitability index (QSI) model for Asia's densely populated cities
No full textNoise pollution is a growing threat to public health in dense cities yet widely used quietness indices were calibrated in European contexts and transfer poorly to Asian megacities. This study proposed the Adaptive Quietness Suitability Index (AQSI), a refined, validated framework that enhances sensitivity, accuracy, and transferability in mixed-use urban environments. The AQSI advances three elements: (i) dynamic impact-zone delineation via physics-based sound propagation rather than fixed buffers, (ii) alignment with locally regulated noise limits and control zones, and (iii) explicit temporal stratification (daytime, evening, nighttime, all-day) to capture diurnal variability. We validated the AQSI using monitoring data from 1997 to 2024 in New Taipei City, Taiwan, and compared it to the original QSI through regression and spatial analyses. The AQSI showed stronger agreement with measured sound levels than the original QSI (Pearson’s r = −0.238 vs. −0.202), representing a 39 % improvement in explained variance (R 2 = 0.057 vs. 0.041). It eliminated extreme-value saturation (0 or 1 in 86.2 % of cells) and reduced it to 0 %, yielding continuous gradients that better resolved intermediate environments. Nighttime emerged as the critical period, with the steepest negative coefficient (−0.0142, p < 0.001) and the highest adjusted R 2 (0.16), highlighting the need for nocturnal noise management. By integrating operational mapping with soundscape-aware considerations at a 50 m resolution, the AQSI provides a transparent, context-sensitive tool for urban planning, regulatory compliance, and targeted mitigation in diverse metropolitan settings.補正完畢DE
Stochastic Nature of Voltage-Controlled Charge Dynamics in AlOx Magnetic Tunnel Junctions
No full textSpintronic memristors based on ferromagnetic metal/oxide heterostructures have recently enabled reversible manipulation of both magnetic properties and resistive switching (RS), offering promising prospects for multibit memory and neuromorphic computing. In this study, we investigate the stochastic nature and relaxation processes of charge dynamics induced by localized oxygen vacancy (VO) in AlOx-based magnetic tunnel junctions (MTJs). We observe that random telegraph noise (RTN) exhibits charge stochasticity at specific bias voltages in the low resistance state (LRS), reflecting the competition and transition between charge capture and emission states against the thermal energy. This behavior reveals that the thermally unstable charge stochasticity originates from localized traps in the AlOx barrier. In contrast, the high resistance state (HRS) favors the RTN emission states, indicating the dominance of direct tunneling effects. Through numerical calculations based on the tight-binding (TB) model and experimental results, we demonstrate that voltage-driven shifts in the VO position within the AlOx barrier, associated with RS, govern the charge dynamics of the MTJs investigated. These findings provide valuable insights and practical implications for the development of next-generation devices leveraging charge stochasticity in AlOx-based MTJs.補正完畢US
Discourse Approach in Organizational Communication Studies: Exploring the Field
No full text組織如語言，該句話說明了：以語言為核心的理論在管理研究與組織研究的領域中漸受重視。隨著語言學的轉向，理論的認識論、本體論、方法論開始轉變，這樣的理論透過「語言」建立起組織傳播研究的核心，從論述與書寫的概念引出「人群（組織）與人之辯證」的思考問題，此乃大問哉。而近年來逐漸高漲的組織論述（organizational discourse）研究興趣，則在積極的企圖與各種學科的編整下反映了這個疑難，即多元的組織傳播相關研究圍繞著論述，發展出「多音」（plurivocality）的諸多組織論述（organizational Discourse）概念。本文認為，儘管論述的知識體系之呈現相當多元，但其對於了解人群與人的辯證關係反而有了更為彈性豐富的視野，面對不同的情境與議題可以對應出較理想的現象詮釋。除此之外，我們可以在諸組織論述理論中找到共同之處，而那些共同之處便是反映了論述概念作為思維核心的價值所在。這個思想與理論的價值便在於回應了Smith 在百年前針對人類組織所提出來的難題（das 'AdamSmith-Problem），這具有當代組織與個人之間協調問題的解釋價值。本文有鑑於此，嘗試去釐清組織傳播研究中論述取徑在當代的面貌，並企圖去整理出一個當代組織論述的知識地圖，並以之作為一個專門的學術領域。補正完畢TW
SMARTPHONE APP ICON ARRANGEMENT STUDY - A PERSONAL INFORMATION MANAGEMENT PERSPECTIVE
No full text使用者安排手機應用程式的方式不盡相同，整理歸納的方法也各有特點，但不管如何安排，共通點是希望能找到所需的應用程式。然而過去相關研究欠缺共同語彙與觀念，以致研究結果無法累積、不利理論架構形成。由於安排手機應用程式與跟整理文件的行為與目標相當類似，因此本研究希望採用個人資訊管理視角來探討手機應用程式的安排。本研究透過觀察、訪談及日誌法，除了瞭解使用者安排應用程式的原則與方法，也探索日常生活當中調整應用程式的模式。研究結果發現手機使用者管理與安排應用程式的模式，與個人資訊管理的活動（資訊保留、組織與維護）一致。在資訊保留方面，使用者會安排應用程式的暫留區域、展現堆疊應用程式的行為。在資訊組織方面，除深入探索Böhmer & Krüger（2013）的相關性、常用性、易用性、美觀性與外部性組織方法之外，本研究並增加預設性與習慣性兩種安排方法；研究亦發現以易用性安排時通常附屬在其他方法之下；某些安排的原因是為了提醒或避免使用應用程式，且可能在堆疊處形成資料夾。在資訊維護方面，使用者的行為包括依據習慣位置調整分類，以及dock上的安排受預設與習慣影響很大。此外，本研究亦提出個人資訊管理角度之手機應用程式安排架構。研究結果有助於對手機應用程式安排的瞭解、結合個人資訊管理理論基礎，亦可作為人機互動應用程式與圖示安排功能概念的發展。補正完畢TW
Photodynamic Agents of Synthetic Curcuminoids with Antibacterial and Anticancer Activities
No full textOur previous study demonstrated that thiophene-substituted synthetic curcumin analogs possessed better antibacterial activity and stability than natural curcumin, demethoxycurcumin, or bisdemethoxycurcumin in antibacterial photodynamic therapy (aPDT). In addition, the activity of the furan-substituted analogs was weaker than that of the thiophene-substituted compounds. As oxygen, sulfur, and selenium belong to the same group in the periodic table, the antibacterial and anticancer activities of these three different elemental analogs were compared and investigated. The thiophene-substituted analog (compound 3) exhibited the most potent antibacterial activity in aPDT experiments. However, the furan-substituted analog (compound 1) exhibited the most potent anticancer activity. These results indicate that the differences in atomic radii or energy levels in these compounds produce different cell-attack results on generated free radicals. Ruthenium(II) complexes have a good reputation for use in PDT for cancer treatment. Our results show that complexation of ruthenium(II) with thiophene-substituted curcumin analogs does not enhance their antibacterial or anticancer activity.補正完畢CH
