Desired Dynamic Equation for Primary Frequency Modulation Control of Gas Turbines

Gas turbines play core roles in clean energy supply and the construction of comprehensive energy systems.The control performance of primary frequency modulation of gas turbines has a great impact on the frequency control of the power grid.However,there are some control difficulties in the primary frequency modulation control of gas turbines,such as the coupling effect of the fuel control loop and speed control loop,slow tracking speed,and so on.To relieve the abovementioned difficulties,a control strategy based on the desired dynamic equation proportional integral(DDE-PI)is proposed in this paper.Based on the parameter stability region,a parameter tuning procedure is summarized.Simulation is carried out to address the ease of use and simplicity of the proposed tuning method.Finally,DDE-PI is applied to the primary frequency modulation system of an MS6001B heavy-duty gas turbine.The simulation results indicate that the gas turbine with the proposed strategy can obtain the best control performance with a strong ability to deal with system uncertainties.The proposed method shows good engineering application potential.

Inverse Design of Phononic Crystal with Desired Transmission via a Gradient-Descent Approach

We propose a general approach based on the gradient descent method to study the inverse problem,making it possible to reversely engineer the microscopic configurations of materials that exhibit desired macroscopic properties.Particularly,we demonstrate its application by identifying the microscopic configurations within any given frequency range to achieve transparent phonon transport through one-dimensional harmonic lattices.Furthermore,we obtain the phonon transmission in terms of normal modes and find that the key to achieving phonon transparency or phonon blocking state lies in the ratio of the mode amplitudes at ends.

On Laozi’s View of Desire

Laozi’s concept of desire has rich ideological connotations,not only referring to reducing personal desires.Laozi’s concept of desire is based on“desire”as human nature,acknowledging the legitimacy and necessity of desire and demand.The rational criticism of“having desire”formed by“no desire”is the value pursuit of Laozi’s concept of desire.From both personal physical and mental aspects and social order,“no desire”plays an important guiding role.Nature is the essence of Laozi’s concept of desire,and being in harmony with nature is the best state of desire.Laozi’s concept of desire reveals a deep spirit of love,and the“ethics of love”highlights Laozi’s strong sense of care for the“other”and ethical attitude towards responsibility.Laozi’s contemplation of desire contains a strong humanistic spirit,with the aim of promoting the healthy and sustainable development of life and society.

马铃薯品种底西瑞(Desiree)悬浮细胞系的建立和培养条件的优化

悬浮细胞培养是植物生物技术中最有用的研究手段之一。本实验对马铃薯品种底西瑞(Desiree)悬浮细胞系建立的方法和优化条件进行了研究。结果表明:马铃薯品种底西瑞(Desiree)细胞生长曲线呈典型的S型,生长周期为2周左右。添加2mg/L 2,4-D+1mg/L NAA的MS培养基最适合底西瑞(Desiree)悬浮细胞的生长,细胞的最佳接种量为7.5mL/50mL。

翻译文学的本土化策略探析——以The World’s Desire两个译本解读为例

目标语意识形态和诗学是影响翻译文学本土化的两个重要操控因素。林纾、周作人对英国冒险小说家哈格德The World’s Desire的翻译有着诸多差异,体现了意识形态和诗学在翻译本土化过程中所发挥的作用。这两个译本折射了翻译文学在中国的传播演变过程,也对中国文学翻译出口有一定的借鉴意义。

A Novel Approach for Trajectory Tracking Control of an Under-Actuated Quad-Rotor UAV

Dear Editor,This letter presents a novel Udwadia-Kalaba(U-K)approach for the trajectory tracking control of a quad-rotor unmanned aerial vehicle(UAV).Compared to conventional control approaches,the desired trajectories are treated as trajectory tracking constraints in this approach.

Optimization and Characterization of Combined Degumming Process of Typha angustata L. Stem Fibers

Plant derived natural fibers have been widely investigated as alternatives to synthetic fibers in reinforcing polymers.Researchers over the years have explored many plant fibers using different extraction processes to study their physical,chemical,and mechanical properties.In this context,the present study relates to the extraction,characterization,and optimization of Typha angustata L.stem fibers.For this purpose,desirability functions and response surface methodology were applied to simultaneously optimize the diameter(D),linear density(LD);yield(Y),lignin fraction(L),and tenacity(T)of Typha stem fibers.Typha stems have been subjected to both alkali(NaOH)and enzymatic(pectinex ultra-SPL)treatments.Three levels of process variables including enzyme concentration(10,15,and 20 ml/L)and treatment duration(10,15,and 20 days)were used to design the experiments according to the factorial design.Experimental results were examined by analysis of variance and fitted to second order polynomial model using multiple regression analysis.The Derringer’s desirability function released that the values of process variables generating optimized diameter,linear density,yield,lignin ratio and tenacity are 20 ml/L and 20 days for concentration of pectinex ultra-SPL enzyme and treatment duration,respectively.Confirmation was performed and high degree of correlation was found between the experimental and statistical values.Moreover,the morphological structure has been investigated by the scanning electron microscope,showing a crenelated structure of ultimate fiber bundles of cellulose composing the Typha fiber.Compared to Typha stem non-treated fibers(TSNTF),Typha stem combined treated fibers(TSCTF),brings to improve mechanical properties.This change in mechanical properties is affected by modifying the fiber structure showing alpha cellulose of(66.86%)and lignin ratio of(10.83%)with a crystallinity index of(58.47%).

拉美亟待破解转型困局

In 2023, Latin America was confronted with increased domestic and international challenges, resulting in a stronger public desire for change. New social ideologies are continuing to emerge, and transformation through reform has become a broad consensus. However, during the complicated reshaping of Latin America's political ecology, the swing of the political pendulum and the change of regimes are accelerating.

Brief Analysis on Naturalism and Realism in Desire Under the Elms

Desire Under the Elms was a drama written by Eugene O'Neill in 1924,which is called the first greatest drama in American history.Through analyzing the naturalistic features in this drama and the combination of naturalism and realism reflected in Desire Under the Elms,this article aims to help readers understand the lines and the relevant connotations better.

A Study on Bible Archetypes in Desire under the Elms

Desire under the Elms reveals a tragedy of spiritual and survival desire of human being. O'Neill creates many Bible archetypes in Desire under the Elms. The thesis analyzes and appreciates Desire under the Elms from aspect of Bible archetype to highlight the destructive power of improper desires in Desire under the Elms.

Storm:a Symbol of Desire—Analysis of The Storm by Kate Chopin

Changes in natural environment are usually the reflection of human inner world.The Storm was a short story written by Kate Chopin,an America female writer.In the story storm not only creates the setting for her immoral behavior,but also symbolizes the female protagonist,Calixta's desire for love.

Prevalence and Risk Factors of Stress Urinary Incontinence Among Perimenopausal Women and Its Influence on Daily Life in Women with Sexual Desire Problem

The prevalence of,and related factors to,stress urinary incontinence (SUI) among perimenopausal Chinese women and its impact on daily life among those women with sexual desire problem in Hubei province were investigated.In this study,1519 perimenopausal women aged 40 to 65 years were selected from three urban communities in the Wuhan area,and two impoverished,mountainous communities in Hubei province,and followed from April to October 2014.Detailed information about demographic characteristics,menstruation,pregnancy,sexual life and chronic diseases was collected.A cross-sectional survey was carried out following information collection by Chi-square test and multiple logistic regression analysis.Univariate and multivariate logistic regression analysis demonstrated that the potential factors associated with developing SUI were old age (OR=3.4,95% CI:1.92-6.04),vaginal delivery (OR=0.623,95% CI:0.45-0.87),low income (OR=0.063,95% CI:0.40-0.92),atrophic vaginitis (OR=1.4,95% CI:1.03-1.80),pelvic organ prolapse (OR=2.81,95% CI:1.36-5.80),chronic pelvic pain (OR=2.17,95% CI:1.90-4.03),constipation (OR=1.44,95% CI:1.07-1.93) and incontinence of feces (OR=3.32,95% CI:2.03-5.43).Moreover,the ratio of SUI (33.2%) was higher than the ratio of urgency urinary incontinence (24.1 %) or the ratio of mixed urinary incontinence (17.4%),and SUI had a greater impact on daily life among women with decreased sexual desire.In conclusion,SUI is a common disorder affecting over one third of the women surveyed,and has a severe impact on the daily life of perimenopausal women with declined sexual desire.Age,mode of delivery,and monthly income are major risk factors involved in the development of SUI.

A cellular automata traffic flow modeling of desired speed variability

The satisfaction rate of desired velocity in the case of a mixture of fast and slow vehicles is studied by using a cellular automaton method. It is found that at low density the satisfaction rate depends on the maximal velocity. However, the behavior of the satisfaction rate as a function of the coefficient of variance is independent of the maximal velocity. This is in good agreement with empirical results obtained by Lipshtat [Phys. Rev. E 79 066110 （2009）]. Furthermore, our numerical result demonstrates that at low density the satisfaction rate takes higher values, whereas the coefficient of variance is close to zero. The coefficient of variance increases with increasing density, while the satisfaction rate decreases to zero. Moreover, we have also shown that, at low density the coefficient variance depends strongly on the probability of overtaking.

A new coupled map car-following model considering drivers' steady desired speed

Based on the pioneering work of Konishi et al., in consideration of the influence of drivers＇ steady desired speed ef/ect on the traffic flow, we develop a new coupled map car-following model in the real world. By use of the control theory, the stability condition of our model is derived. The validity of the present theoretical scheme is verified via numerical simulation, confirming the correctness of our theoretical analysis.

Fuzzy neural network control of underwater vehicles based on desired state programming

Due to the nonlinearity and uncertainty, the precise control of underwater vehicles in some intelligent operations hasn’t been solved very well yet. A novel method of control based on desired state programming was presented, which used the technique of fuzzy neural network. The structure of fuzzy neural network was constructed according to the moving characters and the back propagation algorithm was deduced. Simulation experiments were conducted on general detection remotely operated vehicle. The results show that there is a great improvement in response and precision over traditional control, and good robustness to the model’s uncertainty and external disturbance, which has theoretical and practical value.

核磁共振显微术的DESIRE效应模拟(英文)

要在合理时间內进行微米等级解析度的扫描时,核磁共振波谱的信噪比一直是一个很大的限制. DESIRE效应利用扩散现象来增强信号强度及解析度的概念被提出后,信噪比在一维的情况下大约可以增加一个数量级.在先期的研究中,模拟外加磁场的效应通常是使用叠代数值计算,而扩散的效应则是利用有限微分法解Bloch-Torrey e-quation ,这样的模拟方法通常很耗时.该研究中,分别使用Shinnar-LeRoux演算法及基于旋积的扩散模拟方法来加速计算出外加磁场及扩散对于信号的影响,因此可以节省大量计算时间以进行复杂的计算.利用一维模拟结果预测在不同参数实验中解析度的改变和信号增加值,并找出最佳的参数值.而由模拟结果指出,Sinc3脉冲波形可以得到最佳的信号增加量及不错的解析度.

New Method for Confirming the Desired Safety Headway Distance and Desired Deceleration in ACC System

A new method of confirming the desired safety headway distance and desired deceleration is put forward according to the detected static or moving target and its simulation results in Matlab are also presented. The validity of the algorithm to calculate the reference speeds of both the ACC vehicle and the targeted car according to the vector quadrangle composed of the relative distance, the relative azimuth angle, the relative speeds of the vehicles has also been demonstrated through numerical example in Matlab. New laws to obtain the desired deceleration by estimating the braking force according to the vehicle analyses force equation are established too.

Tarantella——Nora's Dance of Desire

As one of the most well- known plays of Henrik Ibsen, A Doll's House's publishment and premiere in 1879 aroused great controversy on the ideas and beliefs reflected in this play. The female protagonist, Nora, is especially the center of dispute.In Act II, a scene of Nora's dancing Tarantella is worth discussing. It can not only be understood as a way of relieving, but the two men who gives Nora much pressure as well. Tarantella is also a dance of desire which leads to her breakaway from the loveless marriage and her departure from the family.

Death and Desire

Tennessee Williams' successful drama,A Streetcar Named Desire is a world-classic.Its unique plot,well-established structure,and carefully arranged symbols and hints are so attracting that the drama and the characters has been studied and admired by readers around the world.To provide a detailed analysis of the character,this essay will discuss about and compare various aspect of the main character Blanche DuBois.

Symbolic Representation of Blanche DuBois' s Tragic Fate in A Streetcar Named Desire

A Streetcar Named Desire is regarded as one of the most successful masterpieces of Tennessee Williams. An outstanding feature of the play is the wide use of symbolism. Symbols can be seen everywhere and even all the symbols in the play are con nected with the protagonist Blanche DuBois. Williams applies symbolism throughout the play to make Blanche's tragic fate more vivid to the readers. Her tragic fate lies in her clinging to illusion, thus she is bound to be abandoned by the harsh reality. There fore, the thesis attempts to give a comprehensive analysis of some specific symbols: symbols of illusion represented by the Chinese paper lantern and a paper moon, and symbol of reality represented by the light to further illustrate Blanche's tragically symbolic fate.