Research on the optimal path algorithm in multi-level road network

2006-2007 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Influence of the indirect restoration design on the fracture resistance: a finite element study

published_or_final_versio

Frequency domain regression method to calculate response factors of multilayer walls

2000-2001 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Intelligent spider for Internet searching

As World Wide Web (WWW) based Internet services become more popular, information overload also becomes a pressing research problem. Difficulties with searching on the Internet get worse as the amount of information that is available increases. A scalable approach to support Internet search is critical to the success of Internet services and other current or future national information infrastructure (NII) applications. A new approach to build an intelligent personal spider (agent), which is based on automatic textual analysis of Internet documents, is proposed. Best first search and genetic algorithm have been tested to develop the intelligent spider. These personal spiders are able to dynamically and intelligently analyze the contents of the users' selected homepages as the starting point to search for the most relevant homepages based on the links and indexing. An intelligent spider must have the capability to make adjustments according to progress of searching in order to be an intelligent agent. However, the current searching engines do not have communication between the users and the robots. The spider presented in the paper uses Java to develop the user interface such that the users can adjust the control parameters according to the progress and observe the intermediate results. The performances of the genetic algorithm based and best first search based spiders are also reported.published_or_final_versio

Research of influence and mechanism of combining exercise with diet control on a model of lipid metabolism rat induced by high fat diet

OBJECTIVE: To investigate the influence and mechanism of combining exercise with diet control on a model of lipid metabolism rat induced by high fat diet. METHODS: Twenty-four male Wistar rats were randomly divided into 3 groups of 8: normal, model and intervention. The model group and intervention group were fed with high fat diet, while the normal group received basal feed. From day 1, the intervention group was randomly given interventions such as swimming exercise and dietary restriction. The interventions duration were 28 days. At the end of the experiment, the levels of rats’ body weight and liver weight were detected, the serum levels of total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) and hepatic triglyceride content (TG) were detected by using biochemical assay, serum level of gastrin (GAS), motilin (MTL) were assayed by the enzyme linked immunosorbent assay (ELISA). RESULTS: Compared with the level of body weight and liver weight in the normal rats, body weight and liver weight in the rat of the model group were significantly increase (P<0.05 or P<0.01). Plasma concentrations of TC, LDL-C and hepatic TG in the model group were significantly increased compared with those in the normal group (P<0.05 or P<0.01). The contents of GAS, MTL, HDL-C in the model rats’plasma were significantly reduced compared with those of the normal group (P<0.05 or P<0.01). Compared with those in the model group, rats’ body weight, liver weight, serum TC, LDL-C, and TG content of liver in the intervention group decreased significantly (P<0.05 or P<0.01). Meanwhile, serum content of GAS, MTL, HDL-C were significantly improved in the intervention rats compared to the model group. CONCLUSION: The action of combining exercise with diet control for lipid metabolism disorder might be related to regulation of GAS, MTL and other gastrointestinal hormones

Isolation and Characterization of Batatasin III and 3,4’- Dihydroxy-5-methoxybibenzyl: A Pair of Positional Isomers from Sunipia scariosa

Purpose: To isolate and characterize chemical compounds of biological importance from the whole plant of Sunipia scariosa.Methods: The whole plant of Sunipia scariosa was extracted with methanol (MeOH) and chromatographed on silica gel and sephadex LH-20 to afford the pure isolates. High perfomance liquild chromatography (HPLC) was used for further purification of the isolated compounds. Characterization ofthe isolated compounds was achieved by 1H and 13C nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS).Results: Batatasin III (3,3’-dihydroxy-5-methoxybibenzyl) and  3,4’-dihydroxy-5-methoxybibenzyl, a pair of positional isomers, were isolated from the whole plant of Sunipia scariosa. The yields of the two isomers were 60 and 40 %, respectively, from the mixture of two  compounds.Conclusion: Batatasin III and 3,4’-dihydroxy-5-methoxybibenzyl, a pair of positional isomers were successfully isolated from the whole plant of Sunipia scariosa for the first time.Keywords: Sunipia scariosa, Batatasin III, 3,4’-Dihydroxy-5-methoxybibenzyl, Isomer

Economic dispatch savings in the coal-fired power sector: an empirical study of China

© 2018 The current equal share dispatch approach has often been criticized for its negative influence on the electricity system operation in China, which worsens the energy security, environmental sustainability and affordability problems. To provide references for the on-going electricity market reform, this study employs an optimization model to quantify the economic dispatch savings in the coal-fired power sector. Key findings are summarized as follows: (1) The heat rates of 2803 coal generators in China range from 273.91 gce/kWh to 348.38 gce/kWh units in 2014, and the great differences among these generators at different geographical areas exhibit the necessity for economic dispatch. (2) 5.67% of the coal used for power generation could be saved from economic dispatch in a provincial level, the monetary value of which can reduce the average electricity price by 0.0058 yuan/kWh in 2014. (3) Three major political and economic challenges hinder the transition from the current dispatch mode to economic dispatch, namely the insufficient running hours for cost recovery, limited cross-border trading due to electricity over-supply and local protectionism, and the political economy problems from generators of different ownership types.This work was supported by China's National Key R&D Program (2016YFA0602603), National Natural Science Foundation of China (Nos. 71521002, 71273031 and 71573013) and China Scholarship Council (CSC) (201501310015)

Transitions/relaxations in polyester adhesive/PET system

The correlations between the transitions and the dielectric relaxation processes of the oriented poly(ethylene terephthalate) (PET) pre-impregnated of the polyester thermoplastic adhesive have been investigated by differential scanning calorimetry (DSC) and dynamic dielectric spectroscopy (DDS). The thermoplastic polyester adhesive and the oriented PET films have been studied as reference samples. This study evidences that the adhesive chain segments is responsible for the physical structure evolution in the PET-oriented film. The transitions and dielectric relaxation modes’ evolutions in the glass transition region appear characteristic of the interphase between adhesive and PET film, which is discussed in terms of molecular mobility. The storage at room temperature of the adhesive tape involves the heterogeneity of the physical structure, characterized by glass transition dissociation. Thus, the correlation between the transitions and the dielectric relaxation processes evidences a segregation of the amorphous phases. Therefore, the physical structure and the properties of the material have been linked to the chemical characteristics

First two cases of living related liver transplantation with complicated anatomy of blood vessels in Beijing

Aim: Living related liver transplantation (LRLT) has been developed in response to the paediatric organ donor shortage. Though it has been succeeded in many centers worldwide, the safety of the donor is still a major concern, especially in donors with anatomy variation. We succeeded in performing the first two cases of living related liver transplantation with complicated anatomy of blood vessels as a way to overcome cadaveric organ shortage in Beijing. Methods: Two patients, with congenital liver fibrosis and congenital biliary atresia were performed with living donor liver transplantation in our hospital and then followed up from November 12 to December 13, 2001. The two living donors, mother and father, were healthy aged 34 and 35 years. One right lobe (segment V, VI, VII, VIII) and one left lateral lobe (segment II and III) were used. The grafts weighed 394 g and 300 g. The ratio of graff weight to the standard liver volume (SLV) of donors was 68% and 27%. The graft weight to recipient body weight ratio was 3.2% and 4.4%. The graft weight to recipient estimated standard liver mass (ESLM) ratio was 63% and 85%. The two donors had complicated blood vessel variation. Results: Two patients undergone living donor liver transplantation had good results. Abnormal liver function with high bilirubin level appeared in a few days after operation, bur liver function returned to normal one month after operation with bilirubin level almost decreased to near normal. No bleeding, thrombosis, infection and bile leakage occurred. One had an acure rejection and recovered. The two donors recovered in two weeks. One had slight fever because of a little collection in abdomen and recovered after paracentesis and drainage. Conclusion: Living donor liver transplantation has been proved to be a good way that offers a unique opportunity of getting a timely liver graft as a response to shortage of pediatric donors, though it could be a technically difficult operation if there is anatomical variation. Copyright © 2004 by The WJG Press.published_or_final_versio

Detection of 3D rock block contacts by penetration edges

2001-2002 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe