An Empirical Study of the Quality Evaluation in Logistic Service of the B2C E-commerce Companies in China

Ning Lei 보안공학연구지원센터 2014 International Journal of u- and e- Service, Scienc Vol.7 No.5

As the outsourcing of key suppliers and business processes becomes increasingly popular, the evaluation and selection of the logistics outsourcing companies is of critical importance in supply chain management. However, there are few quantitative studies on the investigation of the main affecting factors of the logistics service quality focused on the market in China, which is one of the developing countries with the highest online population growth. This paper is an attempt to identify the main factors affecting the logistics service satisfaction of the B2C e-commerce sites in China, and Fisher’s exact test is applied to identify the main affecting factors of logistics service satisfaction and evaluation. The results could be the guideline for the e-commerce companies in terms of improving their outsourcing logistics services.

Deformation temperature and material constitutive model of cupronickel B10

Ning Lei,Daochun Xu 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.8

Cupronickel B10—an important material used in aircraft carriers—exhibits excellent electrochemical and mechanical properties, such as high corrosion resistance and weldability. The Split-Hopkinson pressure bar (SHPB) test is a classical method to obtain the dynamic mechanical properties of solid materials. However, the deformation temperature has long been ignored in SHPB studies, which results in low accuracy of the material constitutive model. Thus, in this study, a new method for obtained the deformation temperature was proposed and the modified material equation was validated using experimental data. Quasi-static compression and SHPB experiments were conducted with a thermocouple. The results revealed that the deformation temperature of the quasi-static tests was nearly zero, whereas that of the SHPB experiments ranged from 40 to 90 °C. Therefore, the method developed to describe the deformation temperature can be used to improve the precision of SHPB experiments, as demonstrated for the case of cupronickel B10.

Application on Web Page Filtering Technology

Bo Shen,Lei Li,Ning-wei Wang 보안공학연구지원센터 2014 International Journal of Multimedia and Ubiquitous Vol.9 No.12

Web page filtering technology intends to filter out the large number of the repeated and theme-unrelated noise information and obtain useful information. Some web filtering methods cannot make full use of the layout and visual features. In view of the new mainstream “DIV+CSS” designing style of modern commercial web sites, this paper summarizes that elements laying in the same div blocks have common semantic features and proposed a DIV_FOREST model to represent the web pages. And in combination with the Vision-based Page Segmentation Algorithm, a DVPS Algorithm which considers both layout features and visual features was proposed to improve web page filtering efficiency.

Selective transformation of biomass-derived 5-hydroxymethylfurfural into 2,5-dihydroxymethylfuran via catalytic transfer hydrogenation over magnetic zirconium hydroxides

Lei Hu,Mei Yang,Ning Xu,Jiaxing Xu,Shouyong Zhou,Xiao-Zhong Chu,Yijiang Zhao 한국화학공학회 2018 Korean Journal of Chemical Engineering Vol.35 No.1

An economical and effective approach for the selective transformation of biomass-derived 5-hydroxymethylfurfural (HMF) into 2,5-dihydroxymethylfuran (DHMF) was developed by catalytic transfer hydrogenation over various magnetic zirconium hydroxides (MZHs). As expected, MZH with a moderate Zr/Fe molar ratio of 2 displayed the highest catalytic activity, resulting in 98.4% HMF conversion and 89.6% DHMF yield at 150 oC for 5 h in the presence of 2-butanol that simultaneously acted as the hydrogen donor and reaction solvent, which was ascribed to its appropriate specific surface area, pore size and acid-base content. Moreover, a plausible reaction mechanism for the catalytic transfer hydrogenation of HMF into DHMF over MHZ(Zr/Fe=2) was also proposed, in which the basic hydroxyl groups with the aid of acidic zirconium metal centers were considered to be responsible for the pivotal hydride transfer via a six-membered ring structure.

Chemical Constituents from Rhizomes of Curculigo capitulata

Lei Di,Kai-Jin Wang,Cui-Cui Zhu,Ning Li 대한화학회 2010 Bulletin of the Korean Chemical Society Vol.31 No.10

Fabrication of hierarchical structures on concrete surfaces with superhydrophobicity using replicated micro-nano dendritic structures

Ning Wang,Qing Wang,Shuangshuang Xu,Lulu Lei 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.103 No.-

Concrete with superhydrophobicity can protect it from being eroded by water and reduce accumulationof dust. Herein, a green and efficient method was proposed for fabricating hierarchical structures on concretesurfaces with superhydrophobicity by directly replicating micro-nano dendritic structures fromsuperhydrophobic copper mesh to fresh concrete. Microstructures, chemical compositions and wettabilityof the as-fabricated concrete were characterized. Superhydrophobicity of the as-fabricated concretewas studied. Effect of water jet on the as-fabricated concrete was investigated. Wetting durability ofthe as-fabricated concrete were studied. Self-cleaning property was confirmed. It was found that owingto the successful replication of micro-nano dendritic structures and low surface energy stearic acid, theas-fabricated concrete displayed good superhydrophobicity, wetting durability and self-cleaningproperty.

Sustained ocular delivery of desmopressin acetate via thermoreversible in situ gel formulation: preparation and in vitro/in vivo evaluation

Lei Fang,Zhang Huimin,Luo Rui,Fei Qingsong,Bai Luyu,He Ning 한국약제학회 2022 Journal of Pharmaceutical Investigation Vol.52 No.5

Purpose The present study was designed to formulate a thermoreversible in situ gel system for sustained ocular delivery of desmopressin acetate (DDAVP) for the treatment of polyuria. Methods The cold method was employed for the preparation of in situ gel formulations using different levels of poloxamer 407 (F-127) and carboxymethyl chitosan (CMCTS). The optimal formulation was selected based on gelation temperature, rheological behavior, and in vitro drug release, and further evaluated by thermal, ocular irritation, residence time, in vivo pharmacokinetics, and pharmacodynamic analyses. Results The optimal formulation, composed of F-127 (20%) and CMCTS (1.5%), showed appropriate fluidity at room temperature (25 °C) and transitioned to semisolid gels at physiological temperature (34 °C). The optimal gels showed pseudoplastic fluid properties and favorable thixotropy characteristics in rheological tests. Differential scanning calorimetry analysis revealed even dispersal of DDAVP in the matrix of gels. Results from in vivo studies demonstrated that the newly prepared gel successfully prolonged the residence time of DDAVP, improved ocular bioavailability, and exerted the same antidiuretic effect as ophthalmic drops. Conclusion The developed thermoreversible ophthalmic in situ gel of DDAVP presents a promising formulation for the treatment of polyuria.

Study on the micro-scale simulation of wind field over complex terrain by RAMS/FLUENT modeling system

Lei Li,Li-Jie Zhang,Ning Zhang,Fei Hu,Yin Jiang,Chun-Yi Xuan,Wei-Mei Jiang 한국풍공학회 2010 Wind and Structures, An International Journal (WAS Vol.13 No.6

A meteorological model, RAMS, and a commercial computational fluid dynamics (CFD) model, FLUENT are combined as a one-way off-line nested modeling system, namely, RAMS/FLUENT system. The system is experimentally applied in the wind simulation over a complex terrain, with which numerical simulations of wind field over Foyeding weather station located in the northwest mountainous area of Beijing metropolis are performed. The results show that the method of combining a meteorological model and a CFD model as a modeling system is reasonable. In RAMS/FLUENT system, more realistic boundary conditions are provided for FLUENT rather than idealized vertical wind profiles, and the finite volume method (FVM) of FLUENT ensures the capability of the modeling system on describing complex terrain in the simulation. Thus, RAMS/FLUENT can provide fine-scale realistic wind data over complex terrains.

Two new neolignans from Patrinia scabra with potent cytotoxic activity against HeLa and MNK-45 cells

Lei Di,Guo-Qing Yan,Ling-Yu Wang,Wei Ma,Kai-Jin Wang,Ning Li 대한약학회 2013 Archives of Pharmacal Research Vol.36 No.10

Two new neolignans, patrineolignan A (1) andpatrineolignan B (2), together with seven known lignans,were isolated from the 90 % aqueous EtOH extract of theroots of Patrinia scabra. Their structures were elucidatedon the basis of spectroscopic data (HRESIMS, IR, 1D and2D NMR) and comparison with literature data. The twonew neolignans were evaluated in vitro for cytotoxicproperties against human cervical carcinoma HeLa cell lineand gastric carcinoma MNK-45 cell line using the microculturetetrazolium assay, and both 1 and 2 exhibitedstrongly cytotoxic activity against the two tumor cell lines.

Probabilistic structural damage detection approaches based on structural dynamic response moments

Lei, Ying,Yang, Ning,Xia, Dandan Techno-Press 2017 Smart Structures and Systems, An International Jou Vol.20 No.2

Because of the inevitable uncertainties such as structural parameters, external excitations and measurement noises, the effects of uncertainties should be taken into consideration in structural damage detection. In this paper, two probabilistic structural damage detection approaches are proposed to account for the underlying uncertainties in structural parameters and external excitation. The first approach adopts the statistical moment-based structural damage detection (SMBDD) algorithm together with the sensitivity analysis of the damage vector to the uncertain parameters. The approach takes the advantage of the strength SMBDD, so it is robust to measurement noise. However, it requests the number of measured responses is not less than that of unknown structural parameters. To reduce the number of measurements requested by the SMBDD algorithm, another probabilistic structural damage detection approach is proposed. It is based on the integration of structural damage detection using temporal moments in each time segment of measured response time history with the sensitivity analysis of the damage vector to the uncertain parameters. In both approaches, probability distribution of damage vector is estimated from those of uncertain parameters based on stochastic finite element model updating and probabilistic propagation. By comparing the two probability distribution characteristics for the undamaged and damaged models, probability of damage existence and damage extent at structural element level can be detected. Some numerical examples are used to demonstrate the performances of the two proposed approaches, respectively.