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| 1 | Theory of multivariate compound extreme value distribution and its application to extreme sea state prediction显示文摘In this paper, a new type of distribution, multivariate compound extreme value distribution (MCEVD), is introduced by compounding a discrete distribution with a multivariate continuous distribution of extreme sea events. In its engineering application the number over certain threshold level per year is fitting to Poisson distribution and the corresponding extreme sea events are fitting to Nested Logistic distribution, then the Poisson-Nested logistic trivariate compound extreme value distribution (PNLTCED) is proposed to predict extreme wave heights, periods and wind speeds in Yellow Sea. The new model gives more stable and reasonable predicted results. | LIU Defu WANG Liping PANG Liang | 2006 | Chinese Science Bulletin2006，51，23： | 23 |
| 2 | Diel and seasonal variation of methane and carbon dioxide fluxes at Site Guojiaba, the Three Gorges Reservoir显示文摘In order to investigate the CH4and CO2fluxes across the water-gas interface and identify their controlling factors, four diel field campaigns and one monthly sampling campaign during June 2010–May 2011 were carried out at a site near the Three Gorges Dam,China. The averaged CH4and CO2fluxes across the air-water interface from the site were much less than those reported from reservoirs in tropic and temperate regions, and from the natural river channels of the Yangtze River. CH4Fluxes at the site were very low compared to most other reservoirs or natural lakes. One of the most important reasons may be due to the oxidation of CH4in the water column owing to the great water depth and high DO in water in the Three Gorges Reservoir. The averaged monthly CH4and CO2fluxes at the site during the observation year were 0.05 mg/(m2·hr) and 104.43 mg/(m2·hr) respectively with the maximum occurred in July 2010. The monthly CO2fluxes during the observation year were positively correlated to the surface water temperature, and negatively correlated to the air pressure and the surface water pH. The CO2flux showed a positive correlation with DOC to some extent, although not significantly, which indicated that allochthonous organic C was a major source of CO2and biogeochemical processes in this reservoir were C-limited. The significantly positive correlation between the reservoir outflow and the seasonal gas flux indicate the disturbance condition of the water body dominated the seasonal gas emission. | Shangbin Xiao Yuchun Wang Defu Liu Zhengjian Yang Dan Lei Cheng Zhang | 2013 | Journal of Environmental Sciences2013，25，10： | 20 |
| 3 | Poisson-Gumbel Mixed Compound Distribution and its application显示文摘With the development of offshore engineering, the joint probability study for extreme sea environments has been a subject of increasing interest for both mathematicians and engineers. However, the conventional multivariate probability distribution models do not describe the distribution of the occurrences of extreme sea states induced by typhoon, hurricane or winter storm, and thus fail to reflect the probability characteristics of sea environments in all the aspects. Extreme sea environments are typically to be found in storms like typhoon, and the occurrences of such storms in certain sea areas, varying from year to year, may be fitted to a discrete distribution. By compounding the discrete distribution with a bivariate continuous distribution of two extreme sea environments, a new kind of distribution-Bivariate Compound Extreme Value Distribution (BCEVD) is obtained in this note. This study proposes Poisson-Gum-bel Mixed Compound Distribution, one of the particular forms of BCEVD, and gives an | Defu Liu Shuqin Wen Liping Wang | 2002 | Chinese Science Bulletin2002，47，22： | 18 |
| 4 | Breast milk macronutrient composition and the associated factors in urban Chinese mothers显示文摘 | Yang Titi Zhang Yumei Ning Yibing You Lili Ma Defu Zheng Yingdong Yang Xiaoguang Li Wenjun Wang Junkuan Wang Peiyu | 2014 | Chinese Medical Journal2014，，9： | 17 |
| 5 | Optimal guidance of extended trajectory shaping显示文摘To control missile's miss distance as well as terminal impact angle, by involving the timeto-go-nth power in the cost function, an extended optimal guidance law against a constant maneuvering target or a stationary target is proposed using the linear quadratic optimal control theory.An extended trajectory shaping guidance(ETSG) law is then proposed under the assumption that the missile-target relative velocity is constant and the line of sight angle is small. For a lag-free ETSG system, closed-form solutions for the missile's acceleration command are derived by the method of Schwartz inequality and linear simulations are performed to verify the closed-form results. Normalized adjoint systems for miss distance and terminal impact angle error are presented independently for stationary targets and constant maneuvering targets, respectively. Detailed discussions about the terminal misses and impact angle errors induced by terminal impact angle constraint, initial heading error, seeker zero position errors and target maneuvering, are performed. | Wang Hui Lin Defu Cheng Zhenxuan Wang Jiang | 2014 | Chinese Journal of Aeronautics2014，27，5： | 11 |
| 6 | Study on round rice straw bale wrapping silage technology and facilities显示文摘Specific to problems of the existing round bale wrapping machine in China,such as small application scope and failing to satisfy the wrapping demands of round bales of different specifications,a tumbler-type round bale wrapping machine based on wrapping silage with stretch film was designed.By theoretical analysis and preliminary experiments of the corresponding wrapping process,revolving speed of tumbler,speed ratio between tumbler and carrier rollers,and pre-load force of stretch film were determined as experimental factors,while wrapping time and consumption of stretch film per unit mass of round bale were determined as evaluation indexes.Furthermore,quadratic regression orthogonal rotational combination experimental design was adopted to carry out the wrapping experiment.The regression models were set up,and influencing rules of experimental factors on evaluation indexes were also analyzed.The optimal parameter combination scheme was revolving speed of tumbler of 31-32 r/min,speed ratio between tumbler and carrier rollers of 2.6,and pre-load force of stretch film of 20-22 N.Under such a circumstance,the corresponding wrapping time required was 37.7-38.9 s and consumption of stretch film per unit mass of round bale was 3.21-3.46 kg/t.The predicted values and the measured values of evaluation indexes basically coincided with each other and the relative error fell below 5%,which indicated that both the optimized regression models acquired through the wrapping experiment and the relevant parameter optimization results were reliable.To guarantee the quality of rice straw silage,the round bale should be wrapped by no less than five layers of stretch films through the utilization of the tumbler-type round bale wrapping machine.The study results could be used as references for research and development of the round bale wrapping machine. | Liqiao Li Defu Wang Xing Yang | 2018 | International Journal of Agricultural and Biological Engineering2018，11，4： | 5 |
| 7 | The joint long-term distribution of design environmental factors for offshore structures Multivariate probabilities and simulating method显示文摘With the development of ocean engineering, it is one of the most important factors which determine the structural safety, cost and suitable forms of engineerings to select the ocean environmental design criteria. Owing to the complexity , variation and randomness of ocean environmental conditions, the commonly used methods for determining design criteria cannot consider the joint occurring probabilities of several environmental factors ,therefore, lead to overestimate design criteria of them and result in an unnecessary overspend invest in engineering. On the basis of the measured and hindcasting data and the multi-demension joint probability theory, this paper presented the study of the joint loads of wind , wave and current on the offshore structures and its responsible joint probability level with the application of random simulation techniques, and presented the joint design criteria of environmental loads for the realistic design of engineerings. | Shi Jiangang, Liu Defu and Wang Zheng Department of Ocean Engineering and Naval Architecture, Tianjin University, Tianjin 300072, China | 1993 | Acta Oceanologica Sinica1993，12，3： | 3 |
| 8 | Fuel Spray Dynamic Characteristics of GDI High Pressure Injection System显示文摘In order to improve the fuel consumption and exhaust emission for gasoline engines,gasoline direct injection(GDI) system is spotlighted to solve these requirements.Thus,many researchers focus on the investigation of spray characteristics and the fuel formation of GDI injector.This paper presents a complete numerical and experimental characterization of transient gasoline spray from a high pressure injection system equipped with a modern single-hole electric controlled injector in a pressurized constant volume vessel.The numerical analysis is carried out in a one-dimensional model of fuel injection system which is developed in the AVL HYDSIM environment.The experimental analyses are implemented through a self-developed injection rate measurement device and spray evolution visualization system.The experimental results of injection rate and spray dynamics are taken to tune and validate the built model.The visualization system synchronize a high speed CMOS camera to obtain the spray structure,moreover,the captured images are taken to validate the injector needle lift process which is simulated in the model.The reliability of the built model is demonstrated by comparing the numerical results with the experimental data.The formed vortex structure at 0.8 ms is effectively disintegrated at 6.2 ms and the spray dynamics become rather chaotic.The fuel flow characteristics within injector nozzle extremely influence the subsequent spray evolution,and therefore this point should be reconsidered when building hybrid breakup GDI spray model.The spray tip speed reach the maximum at 1.18 ms regardless of the operation conditions and this is only determined by the injector itself.Furthermore,an empirical equation for the spray tip penetration is obtained and good agreement with the measured results is reached at a certain extent.This paper provides a methodology for the investigation of spray behavior and fuel distribution of GDI engine design. | LI Bo LI Yunqing WANG Defu | 2012 | Chinese Journal of Mechanical Engineering2012，25，2： | 3 |
| 9 | cDNA cloning and expression pattern of two enolase genes from the Chinese oak silkworm, Antheraea pernyi显示文摘在这研究,二 enolase 基因从中国橡树蚕被孤立并且描绘, Antheraea perny,它被指定为 enolase 我和 II 分别地。enolase 我 cDNA 顺序是有编码 433 氨基酸的 1302 bp 的一个开的读物框架(ORF ) 的 1712 bp。enolase II cDNA 顺序是有编码 431 氨基酸的 1296 bp 的 ORF 的 1549 bp。二基因的氨基酸序列分享 enolase 的几个保存特征 / 地点。我显示出的 Antheraea pernyi enolase 93%97% 顺序身份到迄今为止可得到的 lepidopterans 的 enolases,到另外的无脊椎动物的 enolases 的 75%82% 身份,到包括脊椎动物的另外的有机体的 enolases 的 60%72% 身份,植物,和真菌。Antheraea pernyi enolase II 显示出 84% 身份到 Bombyx mori enolase II,而是 60% 身份到 A。pernyi enolase 我。在种系发生的树上, enolase II 从 A 定序。pernyi 和 B。mori 清楚地包括 A 与更高的有机体的 enolase 序列的多数被分开。pernyi 和 B。我定序的 mori enolase。由顺序比较和种系发生的分析,我们从 A 建议那 enolase II。pernyi 和 B。mori 可以是 enolase 总科的一个新成员。Antheraea pernyi enolase 我而 enolase II mRNA 在睾丸和卵巢明确地被表示, mRNA 在所有测试纸巾被发现,建议 enolase II 基因的产品可能与复制有关。抄本许多 A。pernyi enolase 我基因在冷吃惊以后并且显著地是显著地下面调整的在热吃惊以后起来调整,建议那 A。pernyi enolase 我基因可能由温度应力是可诱导的。 | Yanqun Liu Yuping Li Huan Wang Runxi Xia Xisheng Li Haolei Wan Li Qin Defu Jiang Cheng Lu Zhonghuai Xiang | 2010 | Acta Biochimica et Biophysica Sinica2010，42，11： | 2 |
| 10 | Experimental and Numerical Study on Co-combustion Behaviors and NO_(x) Emission Characteristics of Semi-coke and Coal in a Tangentially Fired Utility Boiler显示文摘The utilization of powdery semi-coke as a power fuel in pulverized coal-fired power plants has become a new and potential technique to consume the excess powdery semi-coke.The characteristic of low volatile results in poor combustion performance and high NO_(x) emission,and to co-fire with bituminous coal is a practical strategy to address this problem.However,the co-combustion characteristics and the inherent interaction between semi-coke and coal remain insufficiently understood.In addition,the influences of secondary air arrangement,the boiler operation load,and the fuel type on co-combustion process are still unclear,which is urgent to be further explored.In the present study,experiments and numerical simulations were jointly utilized to inquire into the co-combustion behaviors and NO_(x) emission features of semi-coke and coal.The results demonstrated that the'out-furnace method'was a suitable choice for small-capacity boiler when the proportion of semi-coke was 33%,due to the limited combinations of the semi-coke injection position.It was recommended that semi-coke was preferred to be injected from the middle layers of the furnace under the'in-furnace method'to improve the overall co-combustion performance.The critical value of the separated over fire air ratio in this study was 27.5%,over which a slight drop of carbon content in fly ash could come about.Moreover,the elevation in the proportion of separated over fire air gave rise to the significant decline of NO_(x) concentration.The constricted secondary air arrangement was preferred to be employed due to the high boiler efficiency.The separated over fire air and the surrounding air needed to maintain a wide-open degree to prevent the increase of NO_(x) emissions and the coking of nozzles.For the load reduction regulation method adopted in this study,the NO_(x) concentration first rose and then dropped,while the burnout ratio decreased obviously as the operation load was reduced.Different combinations of coal and semi-coke generated significant influences on co-combustion behaviors within the furnace.The NO_(x )generated by high-volatile fuel (bituminous coal) combustion was mainly affected by volatile-N,while the NO_(x )generated by low-volatile fuel (semi-coke) was mainly impacted by char-N.This study is of guiding significance for the efficient and clean utilization and beneficial to the large-scale application of powder semi-coke in power plants. | WANG Chang’an FENG Qinqin JIN Liyan WANG Zhichao YAO Wei WANGPengqian DU Yongbo ZHANG Xilai YANG Zhongcan CHE Defu | 2021 | Journal of Thermal Science2021，30，4： | 2 |
| 11 | Co-frequency Interference Suppression for Aerostat Passive Bistatic Radar显示文摘Co-frequency interference is frequently encountered in the aerostat passive bistatic radar exploiting frequency modulated broadcasting signals. Independent component analysis(ICA) in frequency domain, one of the classic Blind source separation(BSS) algorithms, is utilized to recover the direct signal in the above scenarios.To solve the permutation problem of the frequency domain BSS, we use the method of correlation in time-frequency domain between the output of ICA and the coarse reference signal achieved by pattern synthesis with nulls in the direction of the interference or reference stations. In order to suppress the interferences and clutters, the separated direct signals of the reference and interference broadcasting signals are fed into a type of two dimensional adaptive filters in space and fast temporal domain. The processing scheme shows good performance in target detection, which is validated by computer simulation. | WANG Feng WEI Shuang JIANG Defu | 2018 | Chinese Journal of Electronics2018，27，3： | 2 |
| 12 | Uncertainty and joint probability of sea ice loads显示文摘Uncertaintyandjointprobabilityofseaiceloads￥LiuDefu;YangYongchun;WangChaoandLiTongkui(OceanUniversityofQingdao,Qingdao266003,... | Liu Defu Yang Yongchun Wang Chao and Li Tongkui(Ocean University of Qingdao, Qingdao 266003, China)(Tianjin University, Tianjin 300072, China)(China Offshore Oil Design Engineering Corporation,Tianjin 300450, China) | 1995 | Acta Oceanologica Sinica1995，14，3： | 2 |
| 13 | Experimental study on baling rice straw silage显示文摘For resolving harvesting technology of fresh rice straw silage and plugging of the round steel-roll baler in China,experimental researches were carried out.For harvesting technology,baling silage and chopping silage were experimented.For the round baler,three kinds of feeding rolls equipped for enhancing feeding capability were experimented separately by reliability.Experimental results indicate:harvesting technology of baling fresh rice straw as silage is practicable;slicing-disc feeding rolls can be used to the baler to resolve plugging in straw-baling course.And through further experiments by reliability and density,optimal structure of the feeding roll is obtained:big and small slicing-discs arranged in interval and inclination,distance between slicing-discs being 30-40 mm. | Wang Defu Dennis R.Buckmaster Jiang Yiyuan Hua Jinling | 2011 | International Journal of Agricultural and Biological Engineering2011，4，1： | 2 |
| 14 | Investigation on the NO reduction with coal char and high concentration CO during oxy-fuel combustion 显示文摘 | Wang Chang'an Du Yongbo Che Defu | 2012 | Energy & Fuels2012，26，12： | 1 |
| 15 | Investigation on the NO reduction with coal char and high concentration CO during oxy-fuel combustion显示文摘 | WANG Chang'an DU Yongbo CHE Defu | 2012 | Energy & Fuels2012，26，12： | 1 |
| 16 | Assessment of Corneal Biomechanical Properties and Their Variation with Age显示文摘 | Ahmed Elsheikh Defu Wang Michael Brown Paolo Rama Marino Campanelli David Pye | 2007 | Current Eye Research2007，，1： | 1 |
| 17 | The decoupling between gas exchange and water potential of Cinnamomum camphora seedlings during drought recovery and its relation to ABA accumulation in leaves显示文摘气候变化将改变降雨格局,从而导致极端干旱事件增多。然而,树木如何协调生理和生化响应来应对干旱-恢复的机制仍不清楚。本研究探讨了干旱-恢复过程中树木生理与生化特征的耦联关系。我们首先将香樟(Cinnamomum camphora)盆栽幼苗种植在水分充足的条件下,然后通过停止浇水以达到干旱处理的目的。当幼苗胁迫至轻度干旱(气孔关闭)和中度干旱(ψxylem=−1.5 MPa)时,分别对其进行复水处理。在干旱及复水4天过程中,我们测定了香樟叶片水势、气体交换、脱落酸以及非结构性碳水化合物的变化规律。我们发现干旱强度在很大程度上决定了香樟的生理与生化响应,并影响其干旱后恢复。轻度干旱导致气孔关闭,并引起叶片脱落酸累积和水势下降,而中度干旱可进一步引起叶片脯氨酸累积和非结构性碳水化合物的变化。干旱强度的增加会导致气体交换恢复滞后,但对水势的恢复无显著影响。另外,干旱与复水过程中水势与气体交换之间的关系存在较大差异:即干旱过程中水势与气体交换存在很强的耦联关系,而这种耦联关系在复水过程中并不存在,其主要原因是由于叶片脱落酸累积,从而延缓了气孔导度的恢复。综上,本研究结果表明,脱落酸可能是导致香樟旱后气孔导度恢复滞后的主要影响因素。此外,干旱强度对树木生理和生化的恢复具有显著影响。 | Honglang Duan Defu Wang Xiaohua Wei Guomin Huang Houbao Fan Shuangxi Zhou Jianping Wu Wenfei Liu David TTissue Songze Wan | 2020 | Journal of Plant Ecology2020，13，6： | 1 |
| 18 | Reactivities of Coals and Synthetic Model Coal under Oxy-fuel Condi- tions 显示文摘 | WANG Chang'an DU Yongbo CHE Defu | 2013 | Thermochimiea Acta2013，553，： | 1 |
| 19 | Effect of jasmonate treatments on leaves of Rosa rugosa‘Plena’and detoxification enzymes and feeding of adult Monolepta hieroglyphica显示文摘To study the effect of jasmonates(JAs)on the resistance of economic forest plants to insects,R osa rugosa‘Plena'leaves were treated with 1 mmol/L jasmonic acid(JA),methyl jasmonate(MeJA)and Z-jasmone,then the content of tannin and total phenol in leaves and the feeding area of Monolepta hieroglyphica adults on leaves were measured.Changes in the activities of detoxification enzymes in adult M.hieroglyphica that had fed on leaves treated with JAs were also studied.Tannin and total phenol levels in leaves increased significantly after treatment with JAs,and tannin level was 1.36–1.55-fold higher than in the control after treatment with 1 mmol/L MeJA.The total content of phenol in leaves treated with 1.0 mmol/L Z-jasmone increased by 1.33–2.20-fold compared with those of the control.The activities of detoxification enzymes in adults were inhibited to differing degrees:activity of alkaline phosphatase(AKP)first increased,then decreased;the activities of acid phosphatase(ACP),glutathione S-transferases(GSTs)and carboxylesterase(CarE)following treatment with 1 mmol/L MeJA were significantly reduced and were 22%–31%,11%–26%,and 11%–31%lower than those of the control,respectively.Moreover,the feeding area of adult M.hieroglyphica on the leaves treated with JAs was significantly reduced(P<0.05).The feeding area of economic forest R.rugosa‘Plena'leaves treated with 1 mmol/L MeJA decreased by 17%–43%compared with that of the control.Moreover,the decrease in the adult M.hieroglyphica feeding area was highly positively correlated with the content of tannin and positively correlated with the contents of total phenol of economic forest R.rugosa‘Plena'leaves.The reduced feeding area of adult M.hieroglyphica was highly negatively correlated with the activities of AKP and ACP and negatively correlated with those of the GSTs.In conclusion,the use of 1 mmol/L MeJA can noticeably decrease the deleterious effects of adult M.hieroglyphica. | Junxin Yan Yi Tan Yaru Lv Fei Wang Yongqiang Zhang Defu Chi | 2021 | Journal of Forestry Research2021，32，3： | 1 |
| 20 | Pyrolysis and combustion characteristics of coals in oxyfuel combustion显示文摘 | Chang’an Wang Xiaoming Zhang Yinhe Liu Defu Che | 2012 | Applied Energy2012，，： | 1 |
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