Cloning of Thienamycin Cylase Gene from Streptomyces Cattleya

Yiguang Wang,Rongfeng Li 한국미생물생명공학회 ( 구 한국산업미생물학회 ) 1994 제2차 한.중 생명공학 심포지움 Vol.- No.-

Security Architecture and Requirements for Wireless Sensor Networks

Yiguang Gong,Feng Ruan,Zhiyong Fan,Jianmin Hou,Ping Mei,Tao Li 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.8

Recently, with the wider application and development of wireless sensor networks (WSNs), security issues become essential for many sensor network applications including environment monitoring, traffic controlling, military sensing, patient status monitoring and so on. In this paper, we summarize the security architecture and requirements, enumerate attacks and countermeasures in wireless sensor networks. In addition, we also summarize key management and introduce several typical key management methods. Which benefit researchers greatly to realizing the situation and trend of state-of-the-art of wireless sensor networks security.

Analyses of Extinction and Flammability Limit of Stretched Premixed Flames Using the Statistical Narrow-Band Model

Yiguang Ju,Kenichi Takita,Masuya Goro,Fengshan Liu,Hong Sheng Guo 대한기계학회 1998 Heat transter conference Vol.7 No.1

Effects of Lonicera japonica extract on performance, blood biomarkers of inflammation and oxidative stress during perinatal period in dairy cows

Zhao Yiguang,Tang Zhiwen,Nan Xuemei,Sun Fuyu,Jiang Linshu,Xiong Benhai 아세아·태평양축산학회 2020 Animal Bioscience Vol.33 No.7

Objective: An experiment was conducted to evaluate the effects of Lonicera japonica extract (LJE) on milk production, rumen fermentation and blood biomarkers of energy metabolism, inflammation and oxidative stress during the perinatal period of Holstein dairy cows. Methods: Eighteen Holstein dairy cows were used in a complete randomized design experiment with 3 dietary treatments and 6 cows per treatment. All cows received the same basal total mixed ration (TMR) including a prepartal diet (1.35 Mcal of net energy for lactation [NEL]/kg of dry matter [DM], 13.23% crude protein [CP]) from –60 d to calving and a postpartal diet (1.61 Mcal of NEL/kg of DM, 17.39% CP) from calving to 30 days in milk (DIM). The 3 dietary treatments were TMR supplemented with LJE at 0 (control), 1 and 2 g/kg DM, respectively. LJE was offered from 21 d before calving to 30 DIM. Dry matter intake (DMI) and milk production were measured daily after calving. Milk and rumen fluid samples were collected on 29 and 30 d after calving. On –10, 4, 14, and 30 d relative to calving, blood samples were collected to analyze the biomarkers of energy metabolism, inflammation and oxidative stress. Results: Compared with control diet, LJE supplementation at 1 and 2 g/kg DM increased DMI, milk yield and reduced milk somatic cell count. LJE supplementation also decreased the concentrations of blood biomarkers of pro-inflammation (interleukin-1β [IL-1β], IL-6, and haptoglobin), energy metabolism (nonesterified fatty acid and β-hydroxybutyric acid) and oxidative stress (reactive oxygen metabolites), meanwhile increased the total antioxidant capacity and superoxide dismutase concentrations in blood. No differences were observed in rumen pH, volatile fatty acid, and ammonia-N (NH3-N) concentrations between LJE supplemented diets and the control diet. Conclusion: Supplementation with 1 and 2 g LJE/kg DM could increase DMI, improve lactation performance, and enhance anti-inflammatory and antioxidant capacities of dairy cows during perinatal period.

Distributed Observers for Tracking a Moving Target by Cooperative Multiple Agents with Time Delays

Xiaoli Wang,Yiguang Hong 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8

This paper is concerned with a leader-follower problem of cooperative multiple agents with a switching interconnection topology and communication delay. Distributed observers are designed for the second-order follower-agents to track a moving target (regarded as an active leader) with unmeasurable velocity and unknown constant input. Dynamic neighbor-based rules, consisting of distributed controllers and observers for the autonomous agents, are developed to keep updating the information of the leader. With the help of an explicitly constructed common Lyapunov function (CLF), it is proved that each agent can track the active leader. Moreover, the tracking error is estimated in a noisy environment and input-to-state stability (ISS) is obtained for the time-delay system.

Identification of floral aromatic volatile compounds in 29 cultivars from four groups of Osmanthus fragrans by gas chromatography–mass spectrometry

Jianxin Fu,Dan Hou,Yiguang Wang,Chao Zhang,Zhiyi Bao,Hongbo Zhao,Shaoqing Hu 한국원예학회 2019 Horticulture, Environment, and Biotechnology Vol.60 No.4

Osmanthus fragrans Lour. is a popular aromatic ornamental plant and its fl owers are used to enhance the color and fragrance of food. In this study, we analyzed the volatiles of 29 cultivars from all four groups of O. fragrans using a solid-phase microextraction (SPME) technique and gas chromatography–mass spectrometry (GC–MS). We identifi ed 41 volatile organic components that were distributed over fi ve diff erent compound classes, with the majority of the volatile components being dominated by alcohols, ketones, and terpenes, which accounted for 56.6–95.06% of the total volatiles in all tested materials except ‘Zao Yingui’. In ‘Zao Yingui’, alcohols, ketones, and terpenes accounted for only 48.19% of the total volatiles. The diversity of the volatile compounds and their relative contents varied among the four groups and cultivars within each group. The major volatile compounds were α-ionone, β-ionone, 2H-β-ionone, linalool, trans -linalool oxide, cis -linalool oxide, epoxy linalool, geraniol ( Z )-ocimene, and γ-decalactone in all tested cultivars, while nerol and ( Z )-3-hexenyl butanoic acid ester were abundant in several cultivars. The 29 cultivars were classifi ed into fi ve clusters in a hierarchical cluster analysis based on their fl oral volatile compounds. The cultivars of diff erent sexes (male vs. hermaphrodite) had no signifi cant diff erences in the relative contents of the major volatile compounds. This study provides valuable information for understanding the chemical composition of the volatile compounds of O. fragrans fl owers as well as a theoretical basis for the origin, development, and application of modern cultivars of O. fragrans.

Energy Efficient Strategies with Mobile Sink for WSNs : A Survey

Feng Ruan,Zhiyong Fan,Yiguang Gong,Jianmin Hou,Ping Mei,Tao Li 보안공학연구지원센터 2016 International Journal of Future Generation Communi Vol.9 No.8

Sink mobility has been widely used to reduce the energy consumption of sensor nodes, which can prolong the lifetime of nodes in wireless sensor networks (WSNs). Researchers found that sink mobility can improve the stability, throughput and lifetime of the very large-scale WSNs. However, sink mobility also causes issues such as data latency and communication overhead. With these properties sink mobility remains more research efforts under different requirements. In this paper we present a survey of energy efficient strategies in WSNs with mobile sink. Firstly, we investigate the existing issues in WSNs. Then we focus on the problem of energy efficient data gathering strategy with mobile sink and present some existing solutions. Finally, we conclude this paper with some potential extensions which need to be further explored.

Effects of radiation on the uncertainty of flame speed determination using spherically propagating flames with CO/CO₂/H₂O dilutions at elevated pressures

Sohn, Chae Hoon,Chen, Zheng,Ju, Yiguang Elsevier 2015 INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER - Vol.86 No.-

<P><B>Abstract</B></P> <P>This work investigates numerically the effects of spectral dependent radiation on laminar flame speed determination using spherically propagating CH<SUB>4</SUB>/air and H<SUB>2</SUB>/air flames with CO/CO<SUB>2</SUB>/H<SUB>2</SUB>O dilutions at elevated pressures. Three different models, adiabatic, optically thin radiation, and fitted statistically narrow band correlated <I>k</I> (FSNB-CK) models, are employed. The effects of radiation-induced negative burned gas velocity, increased density ratio, and chamber confinement induced flow compression are investigated. It is found that compared to the FSNB-CK model, the adiabatic flame model over-predicts the flame speed by 7% and the optically thin model makes more significant under-prediction. Moreover, this discrepancy increases with pressure. The results also show that a large negative velocity in the burned gas is induced by radiative heat loss and magnified further by the flow compression in a small combustion chamber. The radiation-induced negative burned gas velocity causes an under-estimation of flame speed. Moreover, radiation also increases the density ratio between the burned and the unburned gases. The use of the density ratio of adiabatic flame also causes under-prediction of flame speed. Two radiation corrections taking into account of the negative burned gas velocity and the increased density ratio are recommended for flame speed determination using propagating spherical flame for radiative mixtures. The corrections proposed in this study reduce the uncertainty of flame speed due to radiation.</P>

Effects of monochromatic lights on the growth performance, carcass characteristics, eyeball development, oxidation resistance, and cecal bacteria of Pekin ducks

Hua, Dengke,Xue, Fuguang,Xin, Hairui,Zhao, Yiguang,Wang, Yue,Xiong, Benhai Asian Australasian Association of Animal Productio 2021 Animal Bioscience Vol.34 No.5

Objective: Light is a significant component of housing environment in commercial poultry industry. This study was conducted to investigate whether Pekin ducks perform better under monochromatic lights than under white light with respect to their growth performance, carcass quality, eyeball development, oxidation resistance, and cecal bacterial communities. Methods: A total of 320 one-day-old male Pekin ducklings were randomly distributed into five rooms with different light treatments, white, red, yellow, green, and blue light. Each room consisted of 4 replicated pens with 16 ducklings per pen. Results: Blue light significantly decreased fat deposition by decreasing abdominal fat. Long wavelength light, such as red, green, and yellow light, considerably increased the back-to-front eyeball diameter and the red light potentially enlarged the side-to-side eyeball diameter. Besides, the blue light had adverse effects on the oxidation resistance status in terms of increasing the product malonaldehyde of lipid oxidation and decreasing the plasma concentration of total superoxide dismutase. The phyla of Firmicutes had the greatest abundance in the green and blue treatments, while Bacteroidetes in blue treatment was the least. The genus of Faecalibacterium was significantly lower under the red light. Conclusion: The high risk of cecal health status and decreased anti-oxidation activity were observed under blue light. Red, yellow, and green light might increase the risk of oversized eyeball and cecal illness. Therefore, monochromatic lights compared to white light did not show advantages on the performance of housing ducks, it turns out that the white light is the best light condition for grow-out ducks.

Computational studies of diffusion cool flame structures of n-heptane with/without ozone sensitization with a reduced chemistry

손채훈,손진우,Sang Hee Won,Yiguang Ju 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.3

The diffusion cool flame structures of n-heptane are studied numerically with a comprehensively reduced chemistry. For this study, nheptane/oxygen diffusion flame is self-sustained in a counterflow flame configuration with ozone sensitization. N-heptane is diluted bynitrogen to lower flame temperature and a small amount of ozone is added to oxygen to enhance oxygen atom production. N-heptanediffusion flame shows both hot-flame and cool-flame behaviors in high and low temperature regimes, respectively. Its S-shaped curvehas two upper branches of hot and cool flame branches. The upper branch of cool flame is observed at low strain rates with the order ofmagnitude from O(1) to O(102) s-1 and its zone is much narrower than that of hot flame. N-heptane cool flame survives irrespective ofozone addition, but ozone extends the viable or stable flame zone to higher strain rate. Cool-flame temperatures are below 800 K andradical-induced ignition comes into play. N-heptane is highly diluted by nitrogen and extinction strain rate is more sensitive to mole fractionof n-heptane rather than mole fraction of ozone. Heat release rates of elementary reaction steps and concentrations of major radicalsare far lower in cool flames than in hot flames. Main characteristics of cool flame structures at low strain rates and low temperatures areprovided although the present low-temperature kinetics is not complete.