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Competition and Cooperation Mechanism Between Agency Selling and Wholesale: An Application of the Emerging E-commerce Model

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Competition and Cooperation Mechanism Between Agency Selling...

IEEE International Conference on Industrial engineering and engineering Management

作者： Haonan Wang C. K. M. Lee Ping Ji Gang Li Department of Industrial and Systems Engineering The Hong Kong Polytechnic University Hong Kong China Laboratory for Artificial Intelligence in Design Hong Kong Science Park New Territories Hong Kong SAR China School of Intelligent Finance and Business XJTLU Entrepreneur College (Taicang) Xi'an Jiaotong - Liverpool University China School of Management Xi'an Jiaotong University The State Key Lab for Manufacturing Systems Engineering The Key Lab of the Ministry of Education for Process Control and Efficiency Engineering Xi'an China

Recently, the platform economy allows enterprises to collaborate with business partners and provide additional channels for various parties. E-commerce platforms have become integral channels for connecting suppliers with consumers. In the platform economy, agency selling and reselling are two predominant sales models that often coexist for the same product types, resulting in a competitive relationship. This study analyzes transaction data for 30,000 Stock Keeping Units (SKUs) provided by the Chinese e-commerce platforms over one month. We employ three models to compare the sales quantity and profits of manufacturers and online platforms and to identify the most efficient mode for stakeholders based on the model establishment and empirical evidence. Our findings suggest that apart from the existing channel to provide products to customers, manufacturers enter the platform which will increase the profit of platform operators. On the other hand, platform operators may also affect the profit of the manufacturers.

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Diverse metastable diarylacetonitrile radicals generated by polymer mechanochemistry †

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RSC Mechanochemistry

RSC Mechanochemistry 2024年第2期1卷 181-188页

作者： Takumi Yamamoto Daisuke Aoki Koichiro Mikami Hideyuki Otsuka Department of Chemical Science and Engineering Tokyo Institute of Technology 2-12-1 Ookayma Meguro-ku Tokyo 152-8550 Japan otsuka@mac.titech.ac.jp Engineering Division Process Device Innovation Center Panasonic Industry Co. Ltd. 1006 Kadoma Kadoma City Osaka 571-8506 Japan Living Systems Materialogy (LiSM) Research Group International Research Frontiers Initiative (IRFI) Tokyo Institute of Technology 4259 Nagatsuta-cho Midori-ku Yokohama 226-8501 Japan

Fluorescent radicals have attracted great attention as luminescent materials, mostly on account of their potential to achieve higher luminescence efficiency than closed-shell molecules. However, analyzing fluorescent radicals at ambient conditions remains a challenging task, because radicals are usually unstable in air. In addition, to the best of our knowledge, research aimed at controlling fluorescence wavelengths through substituent changes has not yet been accomplished. Here, we report diverse metastable diarylacetonitrile (DAAN) radicals, which contain different substituents, generated by polymeric mechano-chemical reactions. The DAAN radicals, generated by ball-milling powdered polystyrene together with DAAN derivatives, were dispersed within the polystyrene matrix, where they retained their radical state, which allowed measuring solid-state fluorescence spectra. These measurements revealed that a wide range of fluorescence wavelengths from green to red ( λ em,max = 517–635 nm) can be achieved only by changing the substituents on the aromatic rings in these DAAN radicals. This phenomenon has not been observed for the well-studied triarylmethyl radicals. The fluorescence wavelength of these DAAN radicals can be precisely estimated by time-dependent density-functional theory (TD-DFT) calculations. The amount of DAAN radicals generated upon ball-milling is discussed in conjunction with DFT calculations and experimental results. Our results suggest that the orbital interactions with polymeric mechanoradicals, the bond-dissociation enthalpy, and the steric protection of the radical center are of paramount importance for the generation of DAAN radicals. The results of this study can be expected to provide useful guidelines for the development of advanced fluorescent radicals.

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Optimal Load control and Scheduling through Distributed Mixed-integer Linear Programming

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Optimal Load Control and Scheduling through Distributed Mixe...

Mediterranean Conference on control and Automation (MED)

作者： Vassilios Yfantis William Motsch Nico Bach Achim Wagner Martin Ruskowski Department of Mechanical and Process Engineering Chair of Machine Tools and Control Systems Technische Universit&#x00E4 t Kaiserslautern Kaiserslautern Germany Technologie-Initiative SmartFactory KL e.V. Kaiserslautern Germany German Research Center for Artificial Intelligence (DFKI) Kaiserslautern Germany

ISBN: (数字)9781665406734

ISBN: (纸本)9781665406741

This paper presents a mixed-integer linear programming-based optimization model for simultaneous optimal load control and scheduling of distributed systems coupled through their energy consumptions. The subsystems are able to adjust their energy consumption during the execution of a task and aim at minimizing their completion time and energy cost. The overall problem is solved in a distributed fashion, where each subsystem optimizes its individual operation without sharing sensitive information. To this end, dual decomposition is employed and a new algorithm to update the dual variables is presented. It relies on a transformation of the gradient of the quadratically approximated dual function and the subsequent solution of a regression problem. The proposed algorithm makes efficient use of information collected in previous iterations. The solution obtained from the distributed optimization of the subsystems is compared to both a decentral and a system-wide solution, showing that the distributed solution lies close to the global optimum of the process.

关键词： Energy consumption Costs Automation Approximation algorithms Mixed integer linear programming Task analysis Optimization

Understanding and controlling filamentous growth of fungal cell factories: novel tools and opportunities for targeted morphology engineering

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Fungal Biology and Biotechnology 2021年第1期8卷 8页

作者： Meyer, Vera Cairns, Timothy Barthel, Lars King, Rudibert Kunz, Philipp Schmideder, Stefan Müller, Henri Briesen, Heiko Dinius, Anna Krull, Rainer Chair of Applied and Molecular Microbiology Institute of Biotechnology Technische Universität Berlin Straße des 17. Juni 135 Berlin 10623 Germany Chair of Measurement and Control Institute of Chemical and Process Engineering Technische Universität Berlin Straße des 17. Juni 135 Berlin 10623 Germany Chair of Process Systems Engineering School of Life Sciences Technical University of Munich Gregor- Mendel-Str. 4 Freising 85354 Germany Institute of Biochemical Engineering Technische Universität Braunschweig Rebenring 56 Brunswick 38106 Germany Center of Pharmaceutical Engineering Technische Universität Braunschweig Franz-Liszt-Str. 35a Brunswick 38106 Germany

Filamentous fungal cell factories are efficient producers of platform chemicals, proteins, enzymes and natural products. Stirred-tank bioreactors up to a scale of several hundred m³ are commonly used for their cultivation. Fungal hyphae self-assemble into various cellular macromorphologies ranging from dispersed mycelia, loose clumps, to compact pellets. Development of these macromorphologies is so far unpredictable but strongly impacts productivities of fungal bioprocesses. Depending on the strain and the desired product, the morphological forms vary, but no strain- or product-related correlations currently exist to improve process understanding of fungal production systems. However, novel genomic, genetic, metabolic, imaging and modelling tools have recently been established that will provide fundamental new insights into filamentous fungal growth and how it is balanced with product formation. In this primer, these tools will be highlighted and their revolutionary impact on rational morphology engineering and bioprocess control will be discussed. © 2021, The Author(s).

关键词： Aspergillus niger Co-expression network Filamentous fungi Hypothetical proteins Macromorphology Micromorphology Modelling Pellet Polar growth Rheology X-ray micro-computed tomography

Analysis and Design for Hydrogen-Fueled Cascade Solid Oxide Fuel Cell System

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SSRN 2023年

作者： Liu, Peiyuan Zhang, Yongliang Zhu, Jianzhong Han, Minfang Sun, Kaihua Zhong, Haijun Zhang, XueRui State Key Laboratory of Control and Simulation of Power Systems and Generation Equipment Department of Energy and Power Engineering Tsinghua University Beijing100084 China Xuzhou Huatsing Jingkun Energy Co. Ltd. Jiangsu Province 221005 China Petrochemical Research Institute China National Petroleum Corporation Beijing112206 China Institute of Process Engineering Chinese Academy of Sciences Beijing100190 China

Maximizing total fuel utilization is the key to improving the electrical efficiency of solid oxide fuel cell (SOFC) systems. The cascade system can achieve this effectively, but there are fewer studies on hydrogen-fueled cascade systems, and the determination of suitable rated power ratios needs a basis. Because of the characteristics of cascade systems, a fast model that can predict performance at low flow rates and low hydrogen partial pressures is required. Using multiple sets of experimental data, this study developed and validated an improved semi-empirical model, which accurately predicted the industrial-sized cell performance at different flow rates and hydrogen partial pressures. On this basis, the basic parallel and cascade system models were established. The effects of fuel flow rate, rated power ratio, split ratio, and constraints on the system performance were studied and analyzed, and the appropriate design and operation parameters of the cascade system were determined. The results indicated that the cascade system can significantly improve electrical efficiency compared to the parallel system by selecting suitable design parameters. In the example of a 10-kW rated power system design, the cascade system improved the electrical efficiency by over 9% at rated power compared to the parallel system. The results obtained provide valuable reference for related research and offer guidance for system design. © 2023, The Authors. All rights reserved.

关键词： Electrical efficiency

Optimizing Carbon Emissions in Green Logistics for Time-Dependent Routing

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SSRN 2024年

作者： Liu, Yiming Yu, Yang Roberto, Baldacci Tang, Jiafu Sun, Wei State Key Laboratory of Synthetic Automation for Process Industries Institute of Intelligent Data and Systems Engineering Northeastern University Shenyang110819 China Dalian University of Technology School of Economics and Management Liaoning Dalian116024 China Division of Engineering Management and Decision Sciences College of Science and Engineering Hamad Bin Khalifa University Qatar Foundation P.O. Box 34110 Doha Qatar College of Management Science and Engineering Dongbei University of Finance and Economics Shahekou Dalian116026 China Business School Liaoning University Shenyang110316 China

This paper considers a green vehicle routing problem termed the time-dependent green vehicle routing problem with time windows (TDGVRPTW). The TDGVRPTW is an extension of the green vehicle routing problem with time windows in green logistics. It considers time-dependent vehicle speed and aims to minimize carbon emissions. Since the travel times and carbon emissions between locations depend on the departure time from the starting location, optimizing carbon emissions requires determining the optimal departure times from both the depot and customers. This paper presents a branch-price-and-cut (BPC) algorithm to solve the TDGVRPTW. The problem is formulated based on a set-partitioning model. To solve the pricing problem associated with the set-partitioning model, we first define backward non-dominated time-dependent arcs and optimal timed routes. We also introduce three types of routes, forward, backward, and patchwork optimal timed routes, and analyze their characteristics. Then, we introduce a method to adjust the times in backward and patchwork optimal timed routes from the latest to the earliest. We prove that this method guarantees correctness and effectively reduces complexity. We propose a bidirectional labeling algorithm to generate routes. The pricing problem employs state-of-the-art techniques, including limited memory subset row cuts (lm-SRCs), ng-route relaxation, and bucket graphs to enhance the algorithm’s efficiency. The BPC algorithm is tested on a set of instances derived from benchmark instances in the literature. The results demonstrate the effectiveness of the proposed algorithm in solving the TDGVRPTW. © 2024, The Authors. All rights reserved.

关键词： Travel time

Pre-treatment optimization to reduce membrane fouling during produced water treatment with an integrated FO-MD system

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Science Talks

Science Talks 2025年 14卷

作者： Muhammad Saqib Nawaz Sofiane Soukane Muhammad Bilal Asif Veerabhadraiah Gudideni Sultan Alrubaish Noreddine Ghaffour Environmental Sciences and Engineering Program Division of Biological and Environmental Sciences and Engineering (BESE) King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Saudi Arabia Physical Sciences and Engineering Division (PSE) King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Saudi Arabia Energy Systems Division Process & Control Systems Department Saudi Aramco Dhahran Saudi Arabia

During oil exploration, fresh water that is injected into underground reservoirs returns to the surface loaded with hydrocarbons, salts, and other contaminants. This complex solution is typically known as produced water (PW). Generally, different PW streams are generated at a given site, which, after suitable treatment, are sent for re-injection for enhanced oil recovery or to disposal wells. However, there is a potential for water recovery from this hypersaline contaminated stream. Forward osmosis (FO) and membrane distillation (MD) are two low-pressure membrane treatment technologies successfully used in a single hybrid system for PW treatment. During operation, the key foulants on the FO membrane were CaSiO 3 , CaSO 4 , and NaCl, while for MD, they were SiO 2 and CaSO 4 plus emulsified oil, causing pore clogging. Some foulants were tightly bound and not removed by osmotic backwashing or hydraulic flushing, thus requiring pre-treatment. Different pre-treatment techniques, like ion exchange resins and polymeric and ceramic membrane-based ultrafiltration (UF), were assessed in this study. The resins were able to remove bivalent metallic ions successfully from lower concentration streams only and thus caused an increase in FO flux and a reduction in MD flux by disturbing the FO-MD system equilibrium. The higher concentrations of resins and chemicals required for their regeneration make them unsuitable for such applications. On the contrary, PW pre-treated with polymeric and ceramic UF membranes led to increased FO and MD fluxes without any chemical requirement and proved suitable for pre-treatment.

关键词： Pre-treatment Produced water Ion-exchange resins Ultrafiltration Forward osmosis Membrane distillation

Experimental and Theoretical Identifications of Durable Fe–Nx Configurations Embedded in Graphitic Carbon Nitride for Uranium Photoreduction

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SSRN 2022年

作者： Wen, Tao Hong, Jiahui Ma, Ran Wu, Yunchao Liu, Yang Zhang, Sai Wang, Suhua Wang, Xiangke Ai, Yuejie MOE Key Laboratory of Resources and Environmental Systems Optimization College of Environmental Science and Engineering North China Electric Power University Beijing102206 China Guangdong Provincial Key Laboratory of Petrochemical Pollution Process and Control School of Environmental Science and Engineering Guangdong University of Petrochemical Technology Guangdong Maoming525000 China

Uranium extraction from seawater has attracted increasing attentions for nuclear raw material to support the sustainable development of nuclear power plants. However, it is still a grand challenge to overcome the high salinity background and ultra-low uranyl concentration. Herein, we successfully achieved Fe-N x configurations embedded in graphitic carbon nitride (FeN x /g-C 3 N 4 ) through one-step pyrolysis strategy. Our density function theory (DFT) calculations reveal that the site-isolated FeN x centers are the predominant binding sites for U(VI) species, and visible-light photoexcitation can effectively facilitate the electron escaping from FeN x /g-C 3 N 4 surface relative to pure g-C 3 N 4 , which is consequently favorable for electron transfer in the photoreduction conversion of U(VI) to U(IV). Consistent with the theoretical results, the obtained FeN x /g-C 3 N 4 delivers remarkably higher reduction activity with the conversion efficiency of 99% and rate constant of 0.091 min -1 , almost 9.1 and 12.5 times faster than those of g-C 3 N 4 and TiO 2 catalysts, respectively. It is worthwhile to mention that FeN x /g-C 3 N 4 maintains a high level for the extraction of uranium from seawater, endowing the metal-N configurations embedded g-C 3 N 4 as a kind of promising candidate for the sustainable conversion of radionuclides. © 2022, The Authors. All rights reserved.

关键词： Iron compounds

In Situ Low-Temperature Pyrolysis Fabrication Type Ii Bioio3/Bi4o5i2 Heterostructures with Enhanced Visible-Light-Driven Photooxidation Activity

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SSRN 2022年

作者： Wen, Tao Ma, Ran Zhang, Sai Guo, Sisheng Jiang, Zheng Wang, Jian Sun, Mingtai Wang, Suhua Wang, Xiangke MOE Key Laboratory of Resources and Environmental Systems Optimization College of Environment and Chemical Engineering North China Electric Power University Beijing102206 China Guangdong Provincial Key Laboratory of Petrochemical Pollution Process and Control School of Environmental Science and Engineering Guangdong University of Petrochemical Technology Guangdong Maoming525000 China

Novel visible-light-driven heterostructure semiconductors are considered as promising photocatalysts for the elimination of environmental organic pollutants. Herein, a solvent-assisted low-temperature in situ calcination strategy was developed to fabricate type II BiOIO3/Bi4O5I2 heterojunction using BiOIO3 as self-sacrificed template. The phase transition temperature of BiOIO3 was reduced under solvent-assisted operating conditions. By controlling the elevated temperature from 200 to 300 oC, an in situ stepwise pyrolysis reaction occurred during the calcination process, which was described as BiOIO3→BiOIO3/Bi4O5I2→Bi4O5I2. The light absorption edge of different samples significantly red shifted from 385 to 632 nm with the increase of calcination temperature. Meanwhile, two interlocked interface lattice fringes were identified in high resolution transmission electron microscope (HRTEM) of BiOIO3/Bi4O5I2-250, confirming the formation of BiOIO3/Bi4O5I2 heterojunction. The as-obtained BiOIO3/Bi4O5I2 heterojunction demonstrated the optimal photodegradation performance, which brought about 99.4% of bisphenol A (BPA) degraded within 30 min visible light (λ > 420 nm) illumination. Besides, after 5 repeated cycles, the photoactivity of BiOIO3/Bi4O5I2 heterojunction still maintained 91.5%, unfolding its high photostability. The superior photoreactivity of BiOIO3/Bi4O5I2 nanosheets was assigned to the formation of well matched type II heterojunction, which enhanced the separation and migration of photoinduced charge carriers. Superoxide radical (O2·-) and hole (h+) are dominant reactive species in this photodegradation system. Based on quenching experiments and electron paramagnetic resonance (ESR) results, the possible type II heterojunction mechanism of photodegradation process was proposed. This work affords an innovative method for design and construction of type II composites toward sustainable water purification. © 2022, The Authors. All rights reserved.

关键词： Heterojunctions