Supply Chain Coordination Considering Stochastic Demand and Raw Material Quality Defects

Li Yongfei 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.5

This paper solves the coordination strategies of a supplier and a manufacturer separately under the condition of decentralized, centralized and revenue sharing supply chain based on Steinberg non-cooperative game theory. The research presumes: 1)The manufacturer completely inspects materials of supplier; 2) The manufacturer repairs the unqualified products resulting from supplier’s raw material quality defects; 3) the single manufacturer faces a random demand under single period newsboy model. We find out that marginal effect will be enlarged when the manufacturer repairs the unqualified productions. When supply chain is coordinated, EOQ, total profit and total risk-sharing of centralized supply chain are larger than that of non-coordination or decentralized supply chain. The integrated model of revenue sharing supply chain can achieve the performance of centralized supply chain. The establishment of this integration will not be affected by changes in wholesale price of suppliers. Our research can provide some theoretical basis for supply chain to reduce internal and external risk loss costs.

Central role of autophagic UVRAG in melanogenesis and the suntan response

Yang, Yongfei,Jang, Gyu-beom,Yang, Xuanjun,Wang, Qiaoxiu,He, Shanshan,Li, Shun,Quach, Christine,Zhao, Shihui,Li, Fan,Yuan, Zengqiang,Lee, Hye-Ra,Zhong, Hanbing,Liang, Chengyu National Academy of Sciences 2018 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.115 No.33

<P>UV-induced cell pigmentation represents an important mechanism against skin cancers. Sun-exposed skin secretes alpha-MSH, which induces the lineage-specific transcriptional factor MITF and activates melanogenesis in melanocytes. Here, we show that the autophagic tumor suppressor UVRAG plays an integral role in melanogenesis by interaction with the biogenesis of lysosome-related organelles complex 1 (BLOC-1). This interaction is required for BLOC-1 stability and for BLOC-1-mediated cargo sorting and delivery to melanosomes. Absence of UVRAG dispersed BLOC-1 distribution and activity, resulting in impaired melanogenesis in vitro and defective melanocyte development in zebrafish in vivo. Furthermore, our results establish UVRAG as an important effector for melanocytes' response to alpha-MSH signaling as a direct target of MITF and reveal the molecular basis underlying the association between oncogenic BRAF and compromised UV protection in melanoma.</P>

Improving the Thermal Stability of Polybenzoxazines Through Incorporation of Eugenol-Based Benzoxazine

Yongfei Zhu,Junming Su,Runsheng Lin,Peilin Li 한국고분자학회 2020 Macromolecular Research Vol.28 No.5

To introduce the para-position of phenol or aniline moiety into the crosslinked network of polybenzoxazine and improve its thermal stability, benzoxazine based on eugenol and 4,4’-diaminodiphenylmethane (e-ddm) was copolymerized with bisphenol A-aniline-based benzoxazine (b-a) or phenol-aniline-based benzoxazine (p-a). The differential scanning calorimetry and Fourier transform infrared spectroscopy (FTIR) results show that the carbenium ion intermediate from e-ddm could react with the para-position of phenol or aniline in b-a and p-a during the ringopening polymerization process, resulting in that the aniline and phenol moieties were introduced into cross-linked structures of polybenzoxazines. The thermogravimetric analysis (TGA) and TGA interfaced with FTIR results indicate that the thermal stability of polybenzoxazines increased with the incorporation of e-ddm, due to that the volatilization of phenol, aniline and their derivatives was restrained during the thermal degradation processes. Thereby, introducing e-ddm into benzoxazine is a better method of increasing the thermal stability of polybenzoxazine.

Numerical calculation and optimization designs in engine cooling water pump

Li Wei,Wang Chuan,Shi Weidong,Zhao Xiaofan,Yang Yongfei,Pei Bing 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.5

The cavitation damage in the Engine cooling water pump (ECWP) is the key factor that shortens the lifespan of automobile cooling systems, and causes vibration and noise. To improve cavitation performance and external characteristics of ECWP, three optimized models were designed on the basis of WP7 diesel ECWP. The whole flow fields in three models and the prototype pump were numerically simulated, employing the time averaged Navier-Stokes equation, the standard k-ε turbulent model and Zwart-Gerber-Belamri multiphase flow model by ANSYS-CFX software. Pressure distribution, turbulent kinetic energy distribution, bubble volume fraction distribution, external characteristics and cavitation performance of the prototype pump and optimized models were compared and analyzed. The results show that the external characteristics and cavitation performance of the optimized models are significantly better than that in the prototype pump. Through decreasing the inlet blade angle and wrap angle, extending the blade to inlets and extending a certain inclination in the blade, shock loss in blade inlet was reduced and so, the performance of pump will be improved. The flow condition at blade inlet will also be improved greatly, which in turn improves cavitation performance. When reducing the quantity of blades, the excretion coefficient will drop, flow area of blade inlet becomes bigger, but head has a little drop. And the pump optimized by reducing the quantity of blades has the optimal cavitation performance among three optimized models. With the decrease of impeller diameter, the absolute pressure in the critical cavitation point becomes bigger, the inlet bubble volume fraction at the same absolute pressure increases while cavitation performance gets worse. The obtained numerical results were compared with the experimental ones, and the outcome showed the same tendency between the two along with acceptable error.

Comparative analysis of metabolites and in vitro hypoglycemic activity of Taiwanofungus camphoratus cultured using various methods

Ming YongFei,Li Yin,Chu JianZhi,Zhou XiaoShuang,Huang YuXuan,Yang ShuDe,Mu YueJun,Wang Lin,Zhang Rui,Cheng XianHao 한국응용생명화학회 2024 Applied Biological Chemistry (Appl Biol Chem) Vol.67 No.-

Taiwanofungus camphoratus has attracted much attention because it can abundantly produce various active substances that exhibit blood-sugar lowering, immunity improving, and antioxidant properties. Currently, T. camphoratus is cultured using four main methods: cutting wood culture, solid-state fermentation, submerged fermentation, and dish culture. T. camphoratus produces different metabolites under different culture methods. In this study, nontargeted metabolomics was used to compare the metabolites of T. camphoratus produced under these four culture methods. Principal component analysis and supervised partial least squares-discriminant analysis were used to analyze the differences in the metabolites. Moreover, in vitro hypoglycemic activity of T. camphoratus extracts produced under four culture methods was compared by assessing their ability to inhibit the activity of α-glucosidase, α-amylase, and sucrase. A total of 186 metabolites were identified. In total, 127 metabolites were common under the four culture methods. Under solid-state fermentation, submerged fermentation, and cutting wood culture, 12, 1, and 4 metabolites were unique, respectively. The differential metabolites produced by T. camphoratus under four culture methods were mainly triterpenoids, phenolic compounds, and fatty acid compounds. α-glucosidase, α-amylase, and sucrase activity inhibition was the best using T. camphoratus extract obtained under cutting wood culture; the inhibition rates were 55.97%, 51.96%, and 78.02%, respectively, which were comparable to those exhibited by 0.001, 3, and 12 mg/mL acarbose (positive control). The metabolites produced by T. camphoratus and α-glucosidase, α-amylase, and sucrase inhibitory activities were different under the four culture methods. Cutting wood culture exhibited the best enzyme inhibitory activity. This study provided a theoretical basis for further use and development of various culture methods for the rational production of active metabolites of T. camphoratus.

Research and Implementation of U-Learning System Based on Experience API

Xinghua Sun,Yongfei Ye,Jie Yang,Li Hao,Lihua Ding,Haomin Song 한국정보처리학회 2020 Journal of information processing systems Vol.16 No.3

Experience API provides a learner-centered model for learning data collection and learning process recording. In particular, it can record learning data from multiple data sources. Therefore, Experience API provides verygood support for ubiquitous learning. In this paper, we put forward the architecture of ubiquitous learningsystem and the method of reading the learning record from the ubiquitous learning system. We analyze students’learning behavior from two aspects: horizontal and vertical, and give the analysis results. The system canprovide personalized suggestions for learners according to the results of learning analysis. According to thefeedback from learners, we can see that this u-learning system can greatly improve learning interest and qualityof learners.

Impact of AhR, CYP1A1 and GSTM1 Genetic Polymorphisms on TP53 R273G Mutations in Individuals Exposed to Polycyclic Aromatic Hydrocarbons

Gao, Meili,Li, Yongfei,Xue, Xiaochang,Long, Jiangang,Chen, Lan,Shah, Walayat,Kong, Yu Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.6

This study was to undertaken to investigate the impacts of AhR, CYP1A1, GSTM1 genetic polymorphisms on the R273G mutation in exon 8 of the tumor suppressor p53 gene (TP53) among polycyclic aromatic hydrocarbons (PAHs) exposed to coke-oven workers. One hundred thirteen workers exposed to PAH and 82 control workers were recruited. We genotyped for polymorphisms in the AhR, CYP1A1, GSTM1, and TP53 R273G mutation in blood by PCR methods, and determined the levels of 1-hydroxypyrene as PAH exposure marker in urine using the high pressure liquid chromatography assay. We found that the distribution of alcohol users and the urinary excretion of 1-OHP in the exposed workers were significantly higher than that of the control workers (p=0.004, p<0.001, respectively). Significant differences were observed in the p53 genotype distributions of smoking subjects (p=0.01, 95%CI: 1.23-6.01) and PAH exposure (p=0.008, 95%CI: 1.24-4.48), respectively. Further, significant differences were observed in the p53 exon 8 mutations for the genetic polymorphisms of Lys/Arg for AhR (p=0.02, 95%CI: 0.70-15.86), Val/Val for CYP1A1 (p=0.04, 95%CI: 0.98-19.09) and null for GSTM1 (p=0.02, 95%CI: 1.19-6.26), respectively. Our findings indicated that polymorphisms of PAH metabolic genes, such as AhR, CYP1A1, GSTM1 polymorphisms may interact with p53 genetic variants and may contribute to PAH related cancers.

Enhanced Toughness and Mechanical Property of Epoxy Resins with Good Shape Memory Behaviors

Longhao Tang,Yanling Wang,Tuo Zhou,Yongfei Li,Qiang Li 한국섬유공학회 2020 Fibers and polymers Vol.21 No.6

Developing shape memory polymers (SMPs) with enough mechanical strength, good toughness and excellentprocessability(mild synthesis conditions) is still a challenge for researchers. Therefore, a series of rigid-flexible epoxy SMPswere prepared based on epoxy resin, trimethylolpropane tris(3-mercaptopropionate) (TMP), and N,N-diglycidyl-4-glycidyloxyaniline (TGE) through thiol-epoxy click-reaction. The effect of sulfide curing agent and modifier on the crosslinknetworks and main features (mechanical strength, toughness, and shape memory performance) of epoxy samples wereinvestigated. Experimental results displayed temperature-dependent modulus and strength with two order of magnitudedifference between room temperature and glass transition temperature (Tg). TGE showed great effect on the improvement ofmechanical properties of the epoxy material, increasing from 724.2 MPa to 1637 MPa, nearly 220 %. Moreover, shapememorytest revealed that prepared epoxy SMPs are capable to fulfil the recovery process within 2 mins as long astemperature elevated to or above Tg, with shape fixity ratio over 99 % and shape recovery ratio above 90 %.

Optimized Thermoelectric Properties of AgSbTe2 through Adjustment of Fabrication Parameters

Jian Zhang,Xiaoying Qin,Di Li,송천준,Yongfei Liu,Hongxing Xin,Tianhua Zou,Yuanyue Li 대한금속·재료학회 2015 ELECTRONIC MATERIALS LETTERS Vol.11 No.1

AgSbTe2 bulk sample is obtained by hot-pressing under different fabricationparameters, and their thermoelectric properties are investigated in thetemperature range of 300 - 550 K. The highest ZT = 0.86 is achieved at475 K for the sample hot-pressed at 423 K and 500MPa due to the lowerthermal conductivity and higher power factor. The results indicate that theoptimized thermoelectric properties can be obtained for AgSbTe2 compoundat the sintering temperature of 423 K under the pressure of 500 MPa.