A Delay-aware Application Protocol for Wireless Sensor Networks

Jun-feng Gao,Hong-guo Zhang,Guang-yi Tang 보안공학연구지원센터 2015 International Journal of Grid and Distributed Comp Vol.8 No.6

Recent advances in micro electro mechanical systems (MEMS), wireless communication, and network technology, wireless sensor networks (WSNs) have become technically and economically feasible. In most case, WSNs are usually applied to many applications that require unattended operation. However unlike traditional networks, WSNs are resource constrained distributed networks. The delay latency, uncertainty and dynamic reliability of the WSNs may strongly impact on the WSNs applications. The information content or meaning of sending and receiving data will happened frequency when exchanging data among these sensor nodes over the WSNs. In addition, the application protocol themselves for data exchange may also impact on the WSNs applications. An inappropriate protocol will result in serious inefficiency so as not to meet application requirement. In order to ensure the reliability, integrity, and the continuity of data operations on the WSNs, this paper presents a delay-aware application protocol for WSNs applications. This protocol is based on ZigBee protocol that is suited for remotely monitor and control because of its low-power. Simulation results show that the protocol is feasible for the wireless sensor network in terms of the reliability, integrity and continuity of data.

A Novel Selenium- and Copper-Containing Peptide with Both Superoxide Dismutase and Glutathione Peroxidase Activities

Xian Feng Zou,Yue Tong Ji,Gui Gao,Xue Jun Zhu,Shao Wu Lv,Fei Yan,Si Ping Han,Xing Chen,Chang Cheng Gao,Jun Qiu Liu,Gui Min Luo 한국미생물 · 생명공학회 2010 Journal of microbiology and biotechnology Vol.20 No.1

Performance and Spatial Succession of a Full-Scale Anaerobic Plant Treating High-Concentration Cassava Bioethanol Wastewater

( Gao Rui Fang ),( Xu Feng Yuan ),( Jia Jia Li ),( Xiao Fen Wang ),( Xu Cheng ),( Wan Bin Zhu ),( Zong Jun Cui ) 한국미생물 · 생명공학회 2012 Journal of microbiology and biotechnology Vol.22 No.8

A novel two-phase anaerobic treatment technology was developed to treat high-concentration organic cassava bioethanol wastewater. The start-up process and contribution of organics (COD, total nitrogen, and NH4+-N) removal in spatial succession of the whole process and spatial microbial diversity changing when sampling were analyzed. The results of the start-up phase showed that the organic loading rate could reach up to 10 kg COD/m3d, with the COD removal rate remaining over 90% after 25 days. The sample results indicated that the contribution of COD removal in the pre-anaerobic and anaerobic phases was 40% and 60%, respectively, with the highest efficiency of 98.5%; TN and NH4+-N had decreased to 0.05 g/l and 0.90 g/l, respectively, and the mineralization rate of total nitrogen was 94.8%, 76.56% of which was attributed to the anaerobic part. The microbial diversity changed remarkably among different sample points depending on the physiological characteristics of identified strains. Moraxellaceae, Planococcaceae, and Prevotellaceae were dominant in the pre-anaerobic phase and Bacteroidetes, Campylobacterales, Acinetobacter, Lactobacillus, Clostridium, and Bacillus for the anaerobic phase. Methanosarcinaceae and Methanosaeta were the two main phylotypes in the anaerobic reactor.

Analysis of Isolated Attosecond Pulse Generation from a Multi-cycle Two-color Pulse

Gao Chen,Feng-Dong Zhang,Yu-Jun Yang,Fu-Ming Guo 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.62 No.1

We theoretically investigate the high-order harmonic and attosecond pulse generation by numerically solving the one-dimensional time-dependent Schr¨odinger equation for a hydrogen atom in a two-color laser field that is synthesized by adding a suitable multi-cycle infrared pulse to a multicycle 800-nm fundamental pulse. Our result clearly shows that with the addition of a suitable second optical field, the electric field profile of the synthesized pulse presents multi-segments and that in the first and the last segments, the amplitudes of the electric field are dramatically suppressed. If this synthesized pulse is adopted as an incident driving pulse, only the amplitude of the electric field in the middle segment makes a major contribution to the plateau and to the cutoff region of the harmonic spectrum. This will cause a wide quasicontinuous spectrum around the cutoff position. Thus, an isolated attosecond pulse can be obtained even if we adopt the synthesized pulse with a multi-cycle pulse duration.

Experimental Evaluation of Accelerated T1rho Relaxation Quantification in Human Liver Using Limited Spin-Lock Times

Feng Zhao,Min Deng,Jing Yuan,Gao-Jun Teng,Anil T Ahuja,Yi-Xiang J. Wang 대한영상의학회 2012 Korean Journal of Radiology Vol.13 No.6

Objective: It was reported lately that to obtain consistent liver T1rho measurement, at 3T MRI using six spin-lock times (SLTs), is feasible. In this study, the feasibility of using three or two SLT points to measure liver T1rho relaxation time was explored. Materials and Methods: Seventeen healthy volunteers underwent 36 examinations. Three representative axial slices were selected to cut through the upper, middle, and lower liver. A rotary echo spin-lock pulse was implemented in a 2D fast field echo sequence. Spin-lock frequency was 500 Hz and the spin-lock times of 1, 10, 20, 30, 40, and 50 milliseconds (ms) were used for T1rho mapping. T1rho maps were constructed by using all 6 SLT points, three SLT points of 1, 20, and 50 ms, or two SLTs of 1 and 50 ms, respectively. Intra-class correlation coefficient (ICC) and Bland and Altman plot were used to assess the measurement agreement. Results: Two examinations were excluded, due to motion artifact at the SLT of 50 ms. With the remaining 34 examinations, the ICC for 6-SLT vs. 3-SLT T1rho measurements was 0.922, while the ICC for 6-SLT vs. 2-SLT T1rho measurement was 0.756. The Bland and Altman analysis showed a mean difference of 0.19 (95% limits of agreement: -1.34, 1.73) for 6-SLT vs. 3-SLT T1rho measurement, and the mean difference of 0.89 (95% limits of agreement: -1.67, 3.45) for 6-SLT vs. 2-SLT T1rho measurement. The scan re-scan reproducibility ICC (n = 11 subjects) was 0.755, 0.727, and 0.528 for 6-SLT measurement, 3-SLT measurement, and 2-SLT measurement, respectively. Conclusion: Adopting 3 SLTs of 1, 20, and 50 ms can be an acceptable alternative for the liver T1rho measurement, while 2 SLTs of 1 and 50 ms do not provide reliable measurement. Objective: It was reported lately that to obtain consistent liver T1rho measurement, at 3T MRI using six spin-lock times (SLTs), is feasible. In this study, the feasibility of using three or two SLT points to measure liver T1rho relaxation time was explored. Materials and Methods: Seventeen healthy volunteers underwent 36 examinations. Three representative axial slices were selected to cut through the upper, middle, and lower liver. A rotary echo spin-lock pulse was implemented in a 2D fast field echo sequence. Spin-lock frequency was 500 Hz and the spin-lock times of 1, 10, 20, 30, 40, and 50 milliseconds (ms) were used for T1rho mapping. T1rho maps were constructed by using all 6 SLT points, three SLT points of 1, 20, and 50 ms, or two SLTs of 1 and 50 ms, respectively. Intra-class correlation coefficient (ICC) and Bland and Altman plot were used to assess the measurement agreement. Results: Two examinations were excluded, due to motion artifact at the SLT of 50 ms. With the remaining 34 examinations, the ICC for 6-SLT vs. 3-SLT T1rho measurements was 0.922, while the ICC for 6-SLT vs. 2-SLT T1rho measurement was 0.756. The Bland and Altman analysis showed a mean difference of 0.19 (95% limits of agreement: -1.34, 1.73) for 6-SLT vs. 3-SLT T1rho measurement, and the mean difference of 0.89 (95% limits of agreement: -1.67, 3.45) for 6-SLT vs. 2-SLT T1rho measurement. The scan re-scan reproducibility ICC (n = 11 subjects) was 0.755, 0.727, and 0.528 for 6-SLT measurement, 3-SLT measurement, and 2-SLT measurement, respectively. Conclusion: Adopting 3 SLTs of 1, 20, and 50 ms can be an acceptable alternative for the liver T1rho measurement, while 2 SLTs of 1 and 50 ms do not provide reliable measurement.

Prevalence of Drug Resistance-Associated Gene Mutations in Plasmodium vivax in Central China

Feng Lu,Bo Wang,Jun Cao,Jetsumon Sattabongkot,Huayun Zhou,Kwonkee Kim,Qi Gao,Eun-Taek Han 대한기생충학열대의학회 2012 The Korean Journal of Parasitology Vol.50 No.4

Resistance of Plasmodium spp. to anti-malarial drugs is the primary obstacle in the fight against malaria, and molecular markers for the drug resistance have been applied as an adjunct in the surveillance of the resistance. In this study, we investigated the prevalence of mutations in pvmdr1, pvcrt-o, pvdhfr, and pvdhps genes in temperate-zone P. vivax parasites from central China. A total of 26 isolates were selected, including 8 which were previously shown to have a lower susceptibility to chloroquine in vitro. For pvmdr1, pvcrt-o, and pvdhps genes, no resistance-conferring mutations were discovered. However, a highly prevalent (69.2%), single-point mutation (S117N) was found in pvdhfr gene. In addition, tandem repeat polymorphisms existed in pvdhfr and pvdhps genes, which warranted further studies in relation to the parasite resistance to antifolate drugs. The study further suggests that P. vivax populations in central China may still be relatively susceptible to chloroquine and sulfadoxine-pyrimethamine.

Response of Saccharomyces cerevisiae to Ethanol Stress Involves Actions of Protein Asrlp

( Jun Mei Ding ),( Xiao Wei Huang ),( Na Zhao ),( Feng Gao ),( Qian Lu ),( Ke Qin Zhang ) 한국미생물 · 생명공학회 2010 Journal of microbiology and biotechnology Vol.20 No.12

During the fermentation process of Saccharomyces cerevisiae, yeast cells must rapidly respond to a wide variety of external stresses in order to survive the constantly changing environment, including ethanol stress. The accumulation of ethanol can severely inhibit cell growth activity and productivity. Thus, the response to changing ethanol concentrations is one of the most important stress reactions in S. cerevisiae and worthy of thorough investigation. Therefore, this study examined the relationship between ethanol tolerance in S. cerevisiae and a unique protein called alcohol sensitive RING/PHD finger 1 protein (Asr1p). A real-time PCR showed that upon exposure to 8% ethanol, the expression of Asr1 was continuously enhanced, reaching a peak 2 h after stimulation. This result was confirmed by monitoring the fluorescence levels using a strain with a green fluorescent protein tagged to the C-terminal of Asr1p. The fluorescent microscopy also revealed a change in the subcellular localization before and after stimulation. Furthermore, the disruption of the Asr1 gene resulted in hypersensitivity on the medium containing ethanol, when compared with the wild-type strain. Thus, when taken together, the present results suggest that Asr1 is involved in the response to ethanol stress in the yeast S. cerevisiae.

Ultrasensitive SERS-Based Immunoassay of Tumor Marker in Serum Using Au-Ag Alloy Nanoparticals and Ag/AgBr Hybrid Nanostructure

Yongfeng Gao,Yuanhui Feng,Lu Zhou,Lucia Petti,Zhe Wang,Jun Zhou,Shusen Xie,Jian Chen,Yanping Qing 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.1

Ultrasensitive detection of alpha-fetoprotein (AFP) is critical for the early diagnosis of liver cancer. In this work, a novel surface-enhanced Raman scattering (SERS)-based immunoassay complex has been successfully developed for the detection of AFP by using the Au-Ag alloy nanoparticals and the Ag/AgBr hybrid nanostructure. As the typical bimetal or metal/semiconductor plasmonic materials, besides the strong SERS enhancement characteristics, the Au-Ag alloy nanoparticals exhibit excellent monodispersity and the Ag/AgBr hybrid nanostructure demonstrates good stability. The experimental results show that the SERS-based immunoassay of AFP presents a low limit of detection of 1.86 fg/mL and a broad dynamic range from 2 fg/mL to 0.8 g/mL. Furthermore, the clinical applicability of the proposed SERS-based immunoassay has been assessed by the detection of AFP in the human serum samples of cancer patient and healthy person. The test data are consistent well with that of chemiluminescence immunoassay (CLIA) in the relative errors of –8.82–8.06% and show better detection sensitivity. It reveals that the proposed immunoassay protocol is significant for giving insight into the design of ultrasensitive biosensor and the point-of-care testing of cancers.

Pullout Behaviour of Different Types of Steel Fibres Embedded in Magnesium Phosphate Cementitious Matrix

Hu Feng,M. Neaz Sheikh,Muhammad N. S. Hadi,Lu Feng,Danying Gao,Jun Zhao 한국콘크리트학회 2019 International Journal of Concrete Structures and M Vol.13 No.4

A series of pullout tests were conducted to investigate the interface bond properties of seven types of steel fibres embedded in the magnesium phosphate cementitious matrix. The micromorphology of the interface transition zone between MPC and different types of fibres was examined by scanning electron microscope. Test results showed that smaller diameter steel fibres with brass coating surface achieved higher average bond strength, higher pullout energy per unit volume and a higher ratio of material use. The end hook deformation provided the mechanical bond locally whereas the deformation along the length of fibre provided the mechanical bond distributed along the fibre. The failure mode and group effect of steel fibres were also investigated and reported.

Using Choice-Based Conjoint Analysis in the China Market of Imported Beer

Zhihua Gao,Zhangjian Wu,Feng Gao,Jun Zhang 한국유통과학회 2018 The Journal of Industrial Distribution & Business( Vol.9 No.6

Purpose - With the rapid economic development, great changes have happened in the Chinese beer market. The scale of imported beer is increasing. However, the sales of native Chinese beer decrease in recent years. It is because more Chinese customers prefer beer with unique attributes than those with lower prices. In order to take an advantage in this market, practitioners should develop new products to satisfy Chinese customers. Scholars have also focused on beer characteristics to estimate consumers’ behavior for improving the development of beer industry. However, most studies are theoretically centered on marketing strategy management or general understanding of the market. It is not enough for us to explain customers’ consumption patterns. Some empirical research did attempt to find out beer attributes that may influence their choice behavior. However, they failed to verify what can increase customers’ utility through a new product. More importantly, few evidences can be found in the literature. Therefore this study explores the major characteristics of imported beer which may associate with customers’ preferences. Research design, data, and methodology - With the results of literature review and focus group interview, we found out four main imported beer attributes and the levels of each factor. A pre-test is constructed to check the problems in the questionnaire protocol. With the results of pre-test, the revised questionnaire is processed among customers who have purchased and had imported beer in China regions such as Beijing, Shanghai, Jiangsu, Guangdong and so on. The choice-based conjoint analysis is applied to analyze the useful data of 205. Results - Results indicate that choice-based conjoint analysis is the effective method to estimate customers’ choice behavior. Results also indicate that country of origin, price, taste, and package affect customers’ preference and the importances of imported beer attributes are significantly different. Conclusions - Country of origin, price, taste, and package are important for customers to make an imported beer choice decision. Marketers should consider these determinants and their importance to develop new products. Moreover, choice-based conjoint analysis should be the useful method for practitioners to develop a new product of imported beer for sustainable business in the competitive industry.