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Tian‐Hao Tu,Ji-Rui WANG,Jian-Qiang GU,Tian-Qi LI,Kun LV,Guo-Xin ZHOU,Zhi-Hong XU 한국곤충학회 2019 Entomological Research Vol.49 No.2
Due to habitat fragmentation, the loss of species diversity has been extensively studied. On the contrary, the effects of habitat fragmentation on functional diversity is still poorly understood. In the Thousand Island Lake, we conducted studies of insect functional diversity on a set of 29 isolated islands. We used 10 functional diversity indices from three aspects (functional richness, functional evenness and functional divergence) to respectively describe functional diversity of insects on sample islands. We found the following results: (i) The functional indices selected could reflect the functional diversity of sample islands and it is further proved that in general, three components of functional diversity were independent of each other; (ii) Sample islands could be divided into two categories, island JSD and the remaining islands; (iii) Functional richness increased with island area and shape index, but had no significant correlation with isolation. Likewise, both functional evenness and functional divergence had no significant correlation with island attributes. The conclusion to emphasize from our research is that: (i) habitat fragmentation reduced the biological functional diversity to some extent, further demonstrating the importance of habitat continuity in biodiversity protection; and (ii) for functional diversity protection of insects in a fragmented landscape, an island which has high approximate shape index values of at least hundred hectare magnitude order has a critical promoting effect.
Zigbee-based Intelligent Home Furnishing
Huang Jinhui,Xue ZiYu,Xu Xu,Tian Siyang 보안공학연구지원센터 2015 International Journal of Smart Home Vol.9 No.1
With the constantly emerging of the high-tech, Household life of intelligent, network, digitization has become a research direction in the field of Internet of things. Against this background, this paper puts forward a set of intelligent household iot system based on ZigBee architecture design. The design scheme can be connected to various devices in the family, In order to realize people and equipment, equipment and equipment between "communication", Greatly convenient people's home life. Because the ZigBee module has many advantages such as save electricity, small volume, low cost .Based on ZigBee smart home system has great research value, and is a good way to promote the speed of the Internet of things into our life, let people know well to the role of the Internet of things and it is convenient for our life.
Xu Tian,Qirong Jiang,Yingdong Wei,Junmin Zhang,Yitao Wei 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6
Phase sequence commutating method among traction feeders results in a neutral section without power supply between two feeders in traction substation of electrified railway. Electric locomotives suffer from a nopower time of more than 100 millisecond when going through the neutral section, during which the power failure and restoration process causes serious over-voltage and over-current problems. A novel railway uninterruptible flexible connector based on two-phase modular multilevel converter structure(MMC-UFC) is proposed in this paper, which can completely eliminate power supply dead zone. System utilization and operational principle are analyzed. Mathematical model of MMC-UFC is built to derive the difference between MMC-UFC. Double close-loop control strategies are given and close-loop control of both upper arm current and lower arm current for MMC converter is proposed to ensure the quality of output current. PSCAD/EMTDC simulations and experiment are carried out to prove the effectiveness of proposed MMC-UFC and its control system.
Xu, Jia,Liu, Chang,Zhou, Lei,Tian, Feng,Tai, Ming-Hui,Wei, Ji-Chao,Qu, Kai,Meng, Fan-Di,Zhang, Ling-Qiang,Wang, Zhi-Xin,Zhang, Jing-Yao,Chang, Hu-Lin,Liu, Si-Nan,Xu, Xin-Shen,Song, Yan-Zhou,Liu, Jun,Z Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.2
Serum alpha-fetoprotein (AFP) is a significant marker for clinical diagnosis and prognosis evaluation in hepatocellular carcinoma (HCC) patients. However, some proportion of liver cancer patients are AFP-negative (AFP ${\leq}$20ng/ml). In order to study the differences between clinicopathological factors and prognosis of alpha-fetoprotein negative and positive patients, a total of 114 cases (41 AFP-negative and 73 AFP-positive) were selected for our research. By systematically statistical analysis, the results demonstrated that compared with AFP-negative patients, AFP-positive examples were more likely to feature cirrhosis nodules, non-complete neoplasm capsules, and a poor Edmondson-steiner grade. Furthermore, AFP-negative patients demonstrated a favorable long-term prognosis. By univariate analysis and multivariate analysis with Cox's proportional hazards model, multiple tumors were found to be independent risk factors for worse survival of AFP negative patients; however, less tumor-free margins, multiple tumors and Edmondson-steiner grades III/IV, proved to be independent risk factors leading to a poor prognosis of AFP positive cases. Finally, we can infer that high levels of AFP signify a highly malignant tumor and unfavorable prognosis.
Hydrothermal Synthesis of La-Mn-hexaaluminates for the Catalytic Combustion of Methane
Xu, Jinguang,Zhijian Tian,Wang, Junwei,Yunpeng Xu,Zhusheng Xu,Lin, Liwn 한국화학공학회 2003 Korean Journal of Chemical Engineering Vol.20 No.2
Hydrothermal synthesis by using urea hydrolysis at 1.0~3.0MPa and 120~130℃ was employed to prepare Mn-substituted hexaaluminate catalysts for methane combustion. The results from DTA-MS demonstrated that CO^2-_3 and OH^- anions co-exist in the hydrothermal reaction. XRD reveals that the components of carbonates of carbonates and hydroxides in the hydrothermal reaction are more favorable than those in the(NH_4)_2CO_3 co-precipitation for the formation of the Mn-substituted hexaaluminate phase. After calcination at 1,200℃ for 2h, LaMnAl_11O_19 is the major phase of the catalyst prepared by the hydrothermal synthesis method while LaAlO_3 is the major one of the catalysts prepared by NH_4OH and (NH_4)_2CO_3 co-precipitation. The catalyst prepared by hydrothermal synthesis has higher activity than that prepared by NH_4OH and (NH_4)CO_3 co-precipitation. The major reason is that more Mn^2+ ions have incorporated into the hexaaluminate lattice. The effect of drying methods on the formation of hexaaluminate phase was also discussed.
( Tian Zhou Liu ),( Bang Xing Wang ),( Jin Tao Guo ),( Yang Zhou ),( Mugweru Julius ),( Moses Njire ),( Yuan Yuan Cao ),( Tian Wu ),( Zhi Yong Liu ),( Chang Wei Wang ),( Yong Xu ),( Tian Yu Zhang ) 한국미생물 · 생명공학회 2015 Journal of microbiology and biotechnology Vol.25 No.9
The combination of trimethoprim (TMP) and sulfamethoxazole (SMX) has been shown to be active against Mycobacterium tuberculosis (Mtb) in clinical tuberculosis (TB) treatment. However, the mechanism of action of TMP-SMX against Mtb is still unknown. To unravel this, we have studied the effect of TMP and SMX by deleting the folP2 gene in Mycobacterium smegmatis (Msm), and overexpressing the Mtb and Msm folP1/2 genes in Msm. Knocking out of the folP2 gene in Msm reduced the minimum inhibitory concentration of SMX 8-fold compared with wild type. Overexpression of the folP1 genes from Mtb and Msm increased the MICs by 4- and 2-fold in Msm for SMX and TMP, respectively. We show a strong correlation between the expression of folP1 and folP2 genes and TMP-SMX resistance in mycobacteria. This suggests that a combination of FolP2 inhibitor and SMX could be used for TB treatment with a better outcome.
Tian Xu,Yuxiang Wu 제어·로봇·시스템학회 2024 International Journal of Control, Automation, and Vol.22 No.7
This paper investigates the adaptive finite-time tracking control problem for a class of constrained purefeedback systems with time-varying delays and unknown initial states. By designing a novel shifting function and using the state transformation, there is no need to know the initial value of states. Instead of employing barrier Lyapunov functions, the modified nonlinear state-dependent functions are constructed to solve the deferred state constraints, avoiding the feasibility conditions on virtual controllers. The effect of time-varying delays is eliminated by combining the radial basis function neural networks with a finite covering lemma, and the requirement that the derivative of time-varying delays should be less than one in Lyapunov-Krasovskii functional method is relaxed. The asymmetric saturation nonlinearity is solved by designing an auxiliary system. The system coordinate transformation is employed to solve the design difficulty brought by the nonaffine structure. Then, an adaptive finite-time tracking control scheme is developed based on the command filtered backstepping technique. The developed control scheme can not only make all states satisfy the asymmetric time-varying constraints after a predefined time, but also guarantee the finite-time tracking performance. Finally, simulation examples are given to demonstrate the effectiveness of the proposed scheme.
온감 형용사 "뜨겁다", "따갑다", "덥다"의 의미와 용법에 대한 비교 연구 -한국어 어휘 교육의 관점에서-
( Tian Xu ),김정남 ( Jung Nam Kim ) 한국텍스트언어학회 2015 텍스트언어학 Vol.39 No.-
This paper attempts to compare and analyze the usage and meanings of the three temperature denoting adjectives ‘뜨겁다’, ‘따갑다’ and ‘덥다’ in formal writing through the examination of 21st Century Sejong Project Corpus. We found three main differences in terms of the types of nouns described by the adjectives. First, ‘뜨겁다’ is used most frequently in the database compared to the other two. Second,‘뜨겁다’ is often used in the communication of food and drinks, ‘따갑다’ in depicting natural lights, and ‘덥다’ in expressing time, food and drinks, places and climate. Although all three can describe human emotions or attitudes(it is idiomatic usage), the ways they are used greatly differ from each other. Additionally, when used in a narrative context, ‘뜨겁다’ is normally paired with human body parts, ‘따갑다’with natural lights, and ‘덥다’ with nouns related to climate and people.The three adjectives can usually be used together to address a noun,but with certain exceptions. Third, for adverbial usages of the three adjectives, ‘뜨겁다’ describes actions done by people (such as get up,hug etc.), process of temperature rising in abstract objects (such as burn and stir up), verbs used for expressing emotions or attitudes (such as welcome, applaud etc.) and so on. In the contrast, ‘따갑다’ is mainly used to modify descriptive verbs for natural lights dropping (like shining and basking etc.), while ‘덥다’ is generally not used for modifying verbs except ‘살다’, ‘자다’.
Amperometric Determination of Nitrite at Poly(Methylene Blue)-Modified Glassy Carbon Electrode
Xu, Guang-Ri,Xu, Guifang,Xu, Ming-Lu,Zhang, Zhengqing,Tian, Yuan,Choi, Han-Nim,Lee, Won-Yong Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.2
Electrochemical characteristics of nitrite ion were investigated at a poly(methylene blue)-modified glassy carbon electrode by cyclic voltammetry and differential pulse voltammetry. The poly(methylene blue)-modified glassy carbon electrode exhibited enhanced anodic signals for nitrite. The effects of key parameters on the detection of nitrite were evaluated at the modified electrode, such as pH, accumulation time, and scan rate. Under optimum condition, the chemically modified electrode can detect nitrite in the concentration range $2.0{\times}10^{-6}$ to $5.0{\times}10^{-4}$ M with the detection limit of $2.0{\times}10^{-6}$ M and a correlation coefficient of 0.999. The detection of nitrite using the chemically modified electrode was not affected by common ions such as $Na^+$, $K^+$, $Ca^{2+}$, $Cl^-$, $HPO_4^{2-}$ and $H_2PO_4^- $. The modified electrode showed good stability and reproducibility. The practical application of the present method was successfully applied to the determination of nitrite ion in cabbage samples.