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A Refueling Scheme Optimization Model for the Voyage Charter with Fuel Price Fluctuation and Ship Deployment Consideration

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Journal of Systems Science and Information 2017年第3期8卷 267-278页

作者： Peng JIA weilun ZHANG Wenhao E Xueshan SUN School of Economics and Management University of Chinese Academy of Sciences Collaborative Innovation Center for Transport Studies Dalian Maritime University Transportation Management College Dalian Maritime University Zhonghuan Information College Tianjin University of Technology

Due to the long operation cycle of maritime transportation and frequent fluctuations of the bunker fuel price, the refueling expenditure of a chartered ship at different time or ports of call make significant difference. From the perspective of shipping company, an optimal set of refueling schemes for a ship fleet operating on different voyage charter routes is an important decision. To address this issue, this paper presents an approach to optimize the refueling scheme and the ship deployment simultaneously with considering the trend of fuel price fluctuations. Firstly, an ARMA model is applied to forecast a time serials of the fuel prices. Then a mixed-integer nonlinear programming model is proposed to maximize total operating profit of the shipping company. Finally, a case study on a charter company with three bulk carriers and three voyage charter routes is conducted. The results show that the optimal solution saves the cost of 437,900 USD compared with the traditional refueling scheme, and verify the rationality and validity of the model.

关键词： voyage charter refueling scheme optimization ship deployment bunker fuel price prediction

Multi-scale mechanotransduction of the poroelastic signals from osteon to osteocyte in bone tissue

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Acta Mechanica Sinica 2020年第4期36卷 964-980页

作者： Xiaogang Wu Chaoxin Li Kuijun Chen Yuqin Sun weilun Yu Meizhen Zhang Yanqin Wang Yixian Qin Weiyi Chen College of Biomedical Engineering Taiyuan University of TechnologyTaiyuan 030024China College of Physical Education Taiyuan University of TechnologyTaiyuan 030024China

In order to quantify the poroelastic mechanical signals conduction and evaluate the biomechanical effectiveness of functional units(osteocyte processes,canaliculi and lacuna)in lacunar-canalicular system(LCS),a multiscale poroelastic finite element model was established by using the Comsol Multiphysics *** poroelastic mechanical signals(pore pressure,fluid velocity,von-Mises stress,strain)were analyzed inside the osteon-osteocyte *** effects of osteocyte(OCY)’s shape(ellipse and circle),long axis directions(horizontal and vertical)and mechanical properties(Elastic modulus and permeability)on its poroelastic responses were *** is found that the OCY processes is the best mechanosensor compared with the OCY body,lacunae and *** mechanotransduction ability of the elliptic shaped OCY is stronger than that of circular *** pore pressure and flow velocity around OCYs increase as the elastic modulus and permeability of OCY *** established model can be used for studying the mechanism of bone mechanotransduction at the multiscale level.

关键词： Osteocyte Lacunar-canalicular system Mechanotransduction Finite element analysis Poroelasticity

Facile synthesis of Li2S@C composites as cathode for Li–S batteries

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Journal of Energy Chemistry 2019年第10期28卷 111-116页

作者： Xin Chen Linfeng Peng Lixia Yuan Rui Zeng Jingwei Xiang weilun Chen Kai Yuan Jie Chen Yunhui Huang Jia Xie State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina State Key Laboratory of Materials Processing and Die & Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina

Lithium sulfide (Li2S) provides a promising route for lithium storage due to high theoretical specific capacity (1166 mAh g-1). The electrochemical performance of Li2S can be significantly enhanced by forming Li2S-carbon composites with the introduction of carbon. However, the complex synthesis method of Li2S-carbon composites restrains the large-scale productivity. Herein, we propose a facile route to prepare carbon coated Li2S-carbon nanotube composites (Li2S@C-CNT) via spray drying and heat treatment, which is a low-cost and large-scale method for facile synthesis of Li2S-carbon composites. For the Li2S@C-CNT composites, Li2S nanoparticles are contacted with surrounding particles due to the 3D CNTs framework. The novel construction not only suppresses the diffusion of polysulfides during cycling, but also remarkably accelerates the transport of electron and ion, resulting in a high specific capacity (1100 mAh g^-1) and good cycling performance. The rational designed architecture and good electrochemical performance of Li2S@C-CNT will pave the avenue for realizing high energy density of Li2S-based batteries.

关键词： Spray drying Li2S@C-CNT Lithium-sulfur batteries

Preparation and characterization of nano-rare earth composite materials:application in selectivity catalytic oxidation of ammonia and its cytotoxicity study

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Journal of Rare Earths 2010年第S1期28卷 362-366页

作者： Chang-Mao hung Department of Vehicle Engineering Yung-Ta Institute of Technology and Commerce316 Chung-Shan RoadLinloPingtung 909Taiwan

The manufacture,physical characterization,environmental applications and cytotoxicity properties of nanocomposites consisting of CuO/CeO2 nano-rare earth composite materials prepared using the coprecipitation method at molar ratio of 6:4 with aqueous solutions of copper nitrate and cerium nitrate were *** performance of the selective catalytic oxidation of ammonia to N2(NH3-SCO) over a CuO/CeO2 nano-rare earth composite materials in a tubular fixed-bed reactor(TFBR) at temperatures from 423 to 673 K in the presence of oxygen was *** catalytic redox behavior was determined by cyclic voltammetry(CV).The nanocomposite particles were characterized by TEM,with a tiny particle size around 10 nm with high dispersion ***,cell cytotoxicity and the percentage cell survival were determined by using 3-(4,5-dimethylthiazol-2-yl)-5(3-carboxymethoxyphenol)-2-(4-sulfophenyl)-2H-tetra-zolium(MTS) assay on human lung MRC-5 cell *** results showed that no apparent cytotoxicity was observed when the MRC-5 was exposed to the CuO/CeO2 nanocomposite materials.

关键词： selective catalytic oxidation (SCO) tubular fixed-bed reactor (TFBR) ammonia CuO/CeO2 nanocomposite material cytotoxicity rare earths

Checking Temporal Duration Properties of Timed Automata

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Journal of Computer Science & Technology 2002年第6期17卷 689-698页

作者：李勇 Dang Van hung State Key Laboratory of Novel Software Technology Department of Computer Science and Technology Nanjing University Nanjing 210093 P.R. China International Institute for Software Technology The United Nations University P.O. Box 3058 Macao SAR P.R. China

In this paper, the problem of checking a timed automaton for a Duration Cal-culus formula of the form Temporal Duration Property is addressed. It is shown that TemporalDuration Properties are in the class of discretisable real-time properties of Timed Automata,and an algorithm is given to solve the problem based on linear programming techniques andthe depth-first search method in the integral region graph of the automaton. The complexityof the algorithm is in the same class as that of the solution of the reachability problem of timedautomata.

关键词： model checking duration calculus timed automata

Genome-wide association study of 23 f lowering phenology traits and 4 f loral agronomic traits in tree peony (Paeonia section Moutan DC.) reveals five genes known to regulate f lowering time

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Horticulture Research 2023年第2期10卷 118-133页

作者： Yuying Li Lili Guo Zhanying Wang Dehui Zhao Dalong Guo John E.Carlson weilun Yin Xiaogai Hou College of Agronomy/College of Tree Peony Henan University of Science and TechnologyLuoyangHenan471023China Luoyang Academy of Agricultural and Forestry Sciences LuoyangHenan471000China College of Forestry Henan University of Science and TechnologyLuoyangHenan471023China Department of Ecosystem Science and Management Pennsylvania State UniversityUniversity ParkPA 16802USA College of Biological Sciences and Technology Beijing Forestry UniversityBeijing 100083China

Tree peony is a unique traditional f lower in China,with large,fragrant,and colorful f ***,a relatively short and concentrated f lowering period limits the applications and production of tree peony.A genome-wide association study(GWAS)was conducted to accelerate molecular breeding for the improvement of f lowering phenology traits and ornamental phenotypes in tree peony.A diverse panel of 451 tree peony accessions was phenotyped for 23 f lowering phenology traits and 4 f loral agronomic traits over 3 *** by sequencing(GBS)was used to obtain a large number of genome-wide single-nucleotide polymorphisms(SNPs)(107050)for the panel genotypes,and 1047 candidate genes were identified by association ***-two related genes were observed during at least 2 years for f lowering,and seven SNPs repeatedly identified for multiple f lowering phenology traits over multiple years were highly significantly associated with five genes known to regulate f lowering *** validated the temporal expression profiles of these candidate genes and highlighted their possible roles in the regulation of f lower bud differentiation and f lowering time in tree *** study shows that GWAS based on GBS can be used to identify the genetic determinants of complex traits in tree *** results expand our understanding of f lowering time control in perennial woody *** of markers closely related to these f lowering phenology traits can be used in tree peony breeding programs for important agronomic traits.

关键词： breeding traits tree

Heterogeneous Structure Design to Strengthen Carbon-Containing CoCrFeNi High Entropy Alloy

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Acta Metallurgica Sinica(English Letters) 2021年第11期34卷 1503-1510页

作者： Xiaomeng Qin Chan hung Shek Department of Materials Science and Engineering City University of Hong KongKowloonHong Kong SAR 999077China

A carbon-containing CoCrFeNi high entropy alloy(HEA)with heterogeneous structures was obtained through thermomechanical treatments,which induced concurrent recrystallization and carbide precipitation in the alloy.A combination of high yield strength(556 MPa)and large uniform elongation(45%)was achieved in the investigated *** enhancement of the strength is attributed to the combined effects of grain refinement,precipitation strengthening and microstructural *** work demonstrated that the heterogeneity design could be realized by thermomechanical processes,which provided a practical strategy for producing HEAs with high performance.

关键词： High entropy alloy Heterogeneous structures Mechanical properties Interstitial

Role of gastric oxidative stress and nitric oxide in formation of hemorrhagic erosion in rats with ischemic brain

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World Journal of Gastroenterology 2006年第4期12卷 574-581页

作者： Chen-Road hung Department of Pharmacology College of MedicineNational Cheng Kung UniversityTainanChina

AIM： To investigate the role of gastric oxidative stress and nitric oxide （NO） in the formation of gastric hemorrhagic erosion and their protection by drugs in rats with ischemic brain. METHODS： Male Wistar rats were deprived of food for 24 h. Under chloral hydrate （300 mg/kg） anesthesia, bilateral carotid artery ligation was performed. The pylorus and carotid esophagus of the rats were also ligated. The stomachs were then irrigated for 3 h with either normal saline or simulated gastric juice containing 100 mmol/L HCI plus 17.4 mmol/L pepsin and 54 mmol/L NaCI. Rats were killed and stomachs were dissected. Gastric mucosa and gastric contents were harvested. The rat brain was dissected for the examination of ischemia by triphenyltetrazolium chloride staining method. Changes in gastric ulcerogenic parameters, such as decreased mucosal glutathione level as well as enhanced gastric acid back-diffusion, mucosal lipid peroxide generation, histamine concentration, luminal hemoglobin content and mucosal erosion in gastric samples, were measured. RESULTS： Bilateral carotid artery ligation produced severe brain ischemia （BI） in rats. An exacerbation of various ulcerogenic parameters and mucosal hemorrhagic erosions were observed in these rats. The exacerbated ulcerogenic parameters were significantly （P〈 0.05） attenuated by antioxidants, such as exogenous glutathione and allopurinol. These gastric parameters were also improved by intraperitoneal aminoguanidine （100 mg/kg） but were aggravated by N^G-nitro-L-argininemethyl ester （L-NAME： 25 mg/kg）. Intraperitoneal L-arginine （0-500 mg/kg） dose-dependently attenuated BI-induced aggravation of ulcerogenic parameters and hemorrhagic erosions that were reversed by L-NAME. CONCLUSION： BI could produce hemorrhagic erosions through gastric oxidative stress and activation of arginine-nitric oxide pathway.

关键词： Lipid peroxide Acid back-diffusion Glutathione AIIopurinol L-arginine Nitric oxide synthase Aminoguanidine

Skew Derivations with Power Central Values on Commutators

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Algebra Colloquium 2015年第3期22卷 479-494页

作者： hung-Yuan Chen Department of Mathematics National Changhua University of Education Changhua City 500 Taiwan

Let R be a prime ring with center Z, 5 ： R → R a nonzero skew derivation, and n a fixed positive integer. In this paper, we show that R is a commutative ring if （i） [（δ（[x, y]）, [x, y]]n = 0 for all x, y ∈ R ... 详细信息

关键词： automorphism prime ring Martindale quotient ring skew derivation Minner