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CFD Based Simulation of LNG Release during Bunkering and Cargo Loading/Unloading Simultaneous Operations of a Containership 被引量:1
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作者 FAN Hongjun CHENG Kang WU Shunping 《Journal of Shipping and Ocean Engineering》 2017年第2期51-58,共8页
In order to reduce waiting time in port for large LNG (liquefied natural gas) fueled ships, it is suggested that LNG STS (ship to ship) bunkering and cargo loading/unloading should be carried out simultaneously. T... In order to reduce waiting time in port for large LNG (liquefied natural gas) fueled ships, it is suggested that LNG STS (ship to ship) bunkering and cargo loading/unloading should be carried out simultaneously. This study investigated the safety zone of an LNG bunkering vessel with 10,000 cubic meters capacity transferring LNG fuel to an LNG fueled 18,000 TEU containership. Four LNG leakage scenarios were identified based on failure frequencies analysis of piping systems and severity of consequence, three-dimension CFD software FLACS was adopted to calculate flammable cloud dispersion after LNG leakage. As a result, we obtained a rectangle dangerous zone (41.3 m ~ 126 m), outside of this dangerous zone can be def'med as safety zone. It is concluded that safety zone of LNG STS bunkering and cargo loading/unloading SIMOPS (simultaneous operations) cannot keep the same, there are different results for different designs and operation locations. Due to high frequencies and severe consequences, two typical scenarios, the leakage of LNG hose and the natural gas releases from bunkering tank's safety relief valve during bunkering, cannot be ignored in similar study. 展开更多
关键词 LNG fueled vessel bunkering simultaneous operations gas dispersion dangerous zone.
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Simultaneous Approximation by Baskakov-Durrmeyer Operator
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作者 齐秋兰 郭顺生 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第1期38-45,共8页
In this paper, we investigate the degree of approximation by Baskakov_Durrmeyer operator for functions which derivatives have only discontinuity points of the first kind on [0,∞) with exponential growth.
关键词 operATORS simultaneous approximation moduli of smoothness
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EQUIVALENT THEOREMS ON SIMULTANEOUS APPROXIMATION BY COMBINATIONS OF BERNSTEIN OPERATORES 被引量:1
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作者 Li Cheng Linsen Xie 《Analysis in Theory and Applications》 2006年第3期246-253,共8页
In this paper we give equivalent theorems on simultaneous approximation for the combinations of Bernstein operators by r-th Ditzian- Totik modulus of smoothness w^rφλ (f, t)(0 ≤ λ≤ 1). We also investigate th... In this paper we give equivalent theorems on simultaneous approximation for the combinations of Bernstein operators by r-th Ditzian- Totik modulus of smoothness w^rφλ (f, t)(0 ≤ λ≤ 1). We also investigate the relation between the derivatives of the combinations of Bernstein operators and the smoothness of derivatives of functions. 展开更多
关键词 Bernstein operators COMBINATION simultaneous approximation moduli of smoothness
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Passively Q-Switched Nd,Cr:YAG Laser Simultaneous Dual-Wavelength Operation at 946 nm and 1.3μm 被引量:2
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作者 林斌 张秋琳 +3 位作者 张东香 冯宝华 何京良 张景园 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第7期76-79,共4页
A diode-end-pumped Q-switched high-efficiency Nd, Cr:YAG laser with simultaneous dual-wavelength emission at 946nm and 1.3μm is demonstrated. The maximum output power of 1.93 W with simultaneous dual-wavelength oper... A diode-end-pumped Q-switched high-efficiency Nd, Cr:YAG laser with simultaneous dual-wavelength emission at 946nm and 1.3μm is demonstrated. The maximum output power of 1.93 W with simultaneous dual-wavelength operation is achieved at an absorbed pump power of 13.32 W and an absorbed slope efficiency of 15.15%. The maximum optical-optical efficiency is 14.49% with pulse widths of 16.38ns at 946nm and 26.65ns at 1.3μm. A maximum total repetition rate of 43.25 kHz is obtained. 展开更多
关键词 YAG as Passively Q-Switched Nd Cr:YAG Laser simultaneous Dual-Wavelength operation at 946 nm and 1.3 of NM ND Cr
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Simultaneous operation for cardiac disease and gastrointestinal malignancy
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作者 Teruo Komokata Mikio Fukueda +4 位作者 Mamoru Kaieda Takayuki Ueno Yoshihumi Iguro Yutaka Imoto Ryuzo Sakata 《World Journal of Gastrointestinal Surgery》 SCIE CAS 2014年第8期146-150,共5页
AIM: To investigate the safety of performing simulta-neous cardiac surgery and a resection of a gastrointes-tinal malignancy. METHODS: Among 3664 elective cardiac operations performed in adults at Kagoshima University... AIM: To investigate the safety of performing simulta-neous cardiac surgery and a resection of a gastrointes-tinal malignancy. METHODS: Among 3664 elective cardiac operations performed in adults at Kagoshima University Hospi-tal from January 1991 to October 2009, this study reviewed the clinical records of the patients who un-derwent concomitant cardiac surgery and a gastroin-testinal resection. Such simultaneous surgeries were performed in 15 patients between January 1991 and October 2009. The cardiac diseases included 8 cases of coronary artery disease and 7 cases with valvular heart disease. Gastrointestinal malignancies included 11 gas-tric and 4 colon cancers. Immediate postoperative andlong-term outcomes were evaluated. RESULTS: Postoperative complications occurred in 5 patients(33.3%), including strokes(n = 1), respiratory failure requiring re-intubation(n = 1), hemorrhage(n = 2), hyperbilirubinemia(n = 1) and aspiration pneu-monia(n = 1). There was 1 hospital death caused by the development of adult respiratory distress syndrome after postoperative surgical bleeding followed aortic valve replacement plus gastrectomy. There was no car-diovascular event in the patients during the follow-up period. The cumulative survival rate for all patients was 69.2% at 5 years. CONCLUSION: Simultaneous procedures are accept-able for the patients who require surgery for both car-diac diseases and gastrointestinal malignancy. In par-ticular, the combination of a standard cardiac operation, such as coronary artery bypass grafting or an isolated valve replacement and simple gastrointestinal resection, such as gastrectomy or colectomy can therefore be safely performed. 展开更多
关键词 simultaneous operation CARDIAC disease GASTROINTESTINAL MALIGNANCY GASTRIC CANCER COLON CANCER
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ON SHAPE-PRESERVING PROPERTIES AND SIMULTANEOUS APPROXIMATION OF STANCU OPERATOR
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作者 Lianying Yun Xueyan Xiang 《Analysis in Theory and Applications》 2008年第2期195-204,共10页
In the present paper, the shape-preserving properties and the monotonicity for convex functions of Stancu operator are given. Moreover, the simultaneous approximation problems of this operator are also considered.
关键词 Stancu operator Shape-preserving property Lipschitz preserving property simultaneous approximation
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Simultaneous Approximation for Szsz-Mirakian-Stancu-Durrmeyer Operators
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作者 Vijay Gupta Naokant Deo Xiaoming Zeng 《Analysis in Theory and Applications》 2013年第1期86-96,共11页
The aim of this work is to generalize Szasz-Mirakian operator in the sense of Stancu-Durrmeyer operators. We obtain approximation properties of these operators. Here we study asymptotic as well as rate of convergence ... The aim of this work is to generalize Szasz-Mirakian operator in the sense of Stancu-Durrmeyer operators. We obtain approximation properties of these operators. Here we study asymptotic as well as rate of convergence results in simultaneous approximation for these modified operators. 展开更多
关键词 Szasz-Mirakian-Stancu-Durrmeyer operator simultaneous approximation asymp- totic rate of convergence.
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SIMULTANEOUS APPROXIMATION BY BERNSTEIN-SIKKEMA OPERATORS
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作者 Xuejiao Jiang Linsen Xie 《Analysis in Theory and Applications》 2008年第3期237-246,共10页
In this paper, we investigate the simultaneous approximation of Bernstein- Sikkema operators, and establish the direct and equivalent theorems by using the Ditzian-Totik modulus of smoothness.
关键词 Bernstein-Sikkema operator modulus of smoothness simultaneous approximation
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EQUIVALENT THEOREMS ON SIMULTANEOUS APPROXIMATION BY COMBINATIONSOF GAMMA OPERATORS
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作者 LiangchengMao Xueyan Xiang Wenshan Yang 《Analysis in Theory and Applications》 2008年第2期149-159,共11页
In this paper, some equivalent theorems on simultaneous approximation for combinations of Gamma operators by weighted moduli of smoothness ωφλ^r(f,t)wφ^s(0≤λ≤1)are given. The relation between derivatives ... In this paper, some equivalent theorems on simultaneous approximation for combinations of Gamma operators by weighted moduli of smoothness ωφλ^r(f,t)wφ^s(0≤λ≤1)are given. The relation between derivatives of combinations of Gamma operators and smoothness of derivatives of functions is also investigated. 展开更多
关键词 Gamma operator simultaneous approximation weighted moduli of smoothness
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EQUIVALENCE THEOREM ON WEIGHTED SIMULTANEOUS L-APPROXIMATION BY MEANS OF SZASZ-KANTOROVICH OPERATORS AND BASKAKOV-KANTOROVICH OPERATORS
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作者 Li Bingzheng Zhejiang University, China 《Analysis in Theory and Applications》 1994年第1期76-87,共12页
The intention of this paper is to give direct and converse results on weighted simultaneous approximation by means of Sz(?)sz-Kantorovich operators and Baskakov-Kantorovich operators in L_p-norms using the weighted Di... The intention of this paper is to give direct and converse results on weighted simultaneous approximation by means of Sz(?)sz-Kantorovich operators and Baskakov-Kantorovich operators in L_p-norms using the weighted Ditzian-Totik modulus of smoothness. 展开更多
关键词 EQUIVALENCE THEOREM ON WEIGHTED simultaneous L-APPROXIMATION BY MEANS OF SZASZ-KANTOROVICH operATORS AND BASKAKOV-KANTOROVICH operATORS Math APPI 七声 Zr
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A Comparison of Arithmetic Operations for Dynamic Process Optimization Approach 被引量:3
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作者 洪伟荣 谭鹏程 +1 位作者 王树青 Pu Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第1期80-85,共6页
A comparison of arithmetic operations of two dynamic process optimization approaches called quasi-sequential approach and reduced Sequential Quadratic Programming(rSQP)simultaneous approach with respect to equality co... A comparison of arithmetic operations of two dynamic process optimization approaches called quasi-sequential approach and reduced Sequential Quadratic Programming(rSQP)simultaneous approach with respect to equality constrained optimization problems is presented.Through the detail comparison of arithmetic operations,it is concluded that the average iteration number within differential algebraic equations(DAEs)integration of quasi-sequential approach could be regarded as a criterion.One formula is given to calculate the threshold value of average iteration number.If the average iteration number is less than the threshold value,quasi-sequential approach takes advantage of rSQP simultaneous approach which is more suitable contrarily.Two optimal control problems are given to demonstrate the usage of threshold value.For optimal control problems whose objective is to stay near desired operating point,the iteration number is usually small.Therefore,quasi-sequential approach seems more suitable for such problems. 展开更多
关键词 dynamic optimization arithmetic operation comparison quasi-sequential approach simultaneous approach
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POINTWISE SIMULTANEOUS APPROXIMATION BY LEFT GAMMA QUASI-INTERPOLANTS
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作者 Hongbiao Jiang 《Analysis in Theory and Applications》 2008年第2期120-128,共9页
Recently some classical operator quasi-interpolants were introduced to obtain much faster convergence. We consider left Gamma quasi-interpolants and give a pointwise simultaneous approximation equivalence theorem with... Recently some classical operator quasi-interpolants were introduced to obtain much faster convergence. We consider left Gamma quasi-interpolants and give a pointwise simultaneous approximation equivalence theorem with ωφλ^2r(f,t)∞ by means of unified the classical modulus and Ditzian-Totick modulus. 展开更多
关键词 gamma operator quasi-interpolant pointwise simultaneous approximation equivalent theorem
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农业规模经营与新型城镇化互动关系研究——基于273个地级市的实证分析
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作者 王博 李祺佳 张天星 《西南大学学报(自然科学版)》 北大核心 2026年第1期134-147,共14页
农业规模经营作为农业现代化的核心环节,其发展历程与城镇化建设之间存在密切联系,两者共同构成了推动城乡一体化发展、实现区域协调均衡的战略支点。基于2014-2023年273个地级市数据,构建了联立方程模型,先后应用普通最小二乘法和三阶... 农业规模经营作为农业现代化的核心环节,其发展历程与城镇化建设之间存在密切联系,两者共同构成了推动城乡一体化发展、实现区域协调均衡的战略支点。基于2014-2023年273个地级市数据,构建了联立方程模型,先后应用普通最小二乘法和三阶段最小二乘法进行了实证分析。研究发现:农业规模经营与新型城镇化之间存在显著的正向互动关系,两者的良性互动对于推动农村经济结构的转型和加速城乡一体化发展进程具有重要的促进作用;不同地区农业规模经营与新型城镇化之间的互动关系存在差异,东、西部地区为正向协同关系,中部地区为反向背离关系;胡焕庸线东、西分异较小,仅在影响程度上有所差异;地形异质性分析表明非平地地区农业规模经营与新型城镇化为正向协同关系,平地地区二者为反向背离关系。基于此,当前应畅通城乡间要素流动的渠道,加强顶层设计,以推动新型城镇化与农业规模经营的良性互动,同时应因地制宜,根据不同地区的实际条件制定针对性政策。 展开更多
关键词 新型城镇化 农业规模经营 农业现代化 联立方程模型
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APPROXIMATION BY COMPLEX SZSZ-DURRMEYER OPERATORS IN COMPACT DISKS 被引量:4
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作者 Sorin G.GAL Vijay GUPTA 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1157-1165,共9页
In the present paper, we deal with the complex Szasz-Durrmeyer operators and study Voronovskaja type results with quantitative estimates for these operators attached to analytic functions of exponential growth on comp... In the present paper, we deal with the complex Szasz-Durrmeyer operators and study Voronovskaja type results with quantitative estimates for these operators attached to analytic functions of exponential growth on compact disks. Also, the exact order of approximation is found. 展开更多
关键词 complex Szasz-Durrmeyer operators Voronovksaja type result exact order of approximation in compact disks simultaneous approximation
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Approximation by Complex Baskakov-Szsz-Durrmeyer Operators in Compact Disks
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作者 Sorin G.Gal Vijay Gupta 《Analysis in Theory and Applications》 CSCD 2015年第2期207-220,共14页
In this paper, we deal with the complex Baskakov-Szasz-Durrmeyer mixed operators and study Voronovskaja type results with quantitative estimates for these operators attached to analytic functions of exponential growth... In this paper, we deal with the complex Baskakov-Szasz-Durrmeyer mixed operators and study Voronovskaja type results with quantitative estimates for these operators attached to analytic functions of exponential growth in DR = {z ∈ C; |z| 〈 R}. Also, the exact order of approximation is found. The method used allows to construct complex Szasz-type and Baskakov-type approximation operators without involving the values on [0,∞). 展开更多
关键词 Complex Baskakov-Szzsz-Durrmeyer operators Voronovskaja type result exact or-der of approximation in compact disks simultaneous approximation.
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Simultaneous Approximation by Modified Bernstein-Durrmeyer Operators *
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作者 丁春梅 熊静宜 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2003年第4期609-614,共6页
The aim of the present paper is to prove direct and converse results for simultaneous approximation by modified Bernstein-Durrmeyer operators. A point-wise equivalence characterization of simultaneous approximation is... The aim of the present paper is to prove direct and converse results for simultaneous approximation by modified Bernstein-Durrmeyer operators. A point-wise equivalence characterization of simultaneous approximation is obtained. 展开更多
关键词 Modified Bernstein-Durrmeyer operators simultaneous approximation direct theorem converse theorem.
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带皮神经与失皮神经游离股前外侧皮瓣在舌癌根治术后同期重建中的应用比较分析
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作者 陈虎 孟康 周峰 《实用癌症杂志》 2025年第9期1533-1535,1539,共4页
目的比较研究带皮神经、失皮神经游离股前外侧皮瓣(ALTF)在舌癌根治术后同期重建中的应用效果。方法选取行舌癌根治术的患者70例,按同期重建术式方法的不同分为对照组(n=36)和实验组(n=34)。对照组采用同期失皮神经游离ALTF重建,实验组... 目的比较研究带皮神经、失皮神经游离股前外侧皮瓣(ALTF)在舌癌根治术后同期重建中的应用效果。方法选取行舌癌根治术的患者70例,按同期重建术式方法的不同分为对照组(n=36)和实验组(n=34)。对照组采用同期失皮神经游离ALTF重建,实验组采用同期带皮神经游离ALTF重建。记录两组临床疗效、口腔健康影响程度量表(OHIP-14)评分及并发症发生率。结果术后6个月内实验组总有效率为94.12%,明显高于对照组的72.22%(P<0.05)。术后6个月,两组患者的疼痛与不适、能力受限、功能受限、身心缺陷评分均下降,且实验组评分显著低于对照组(P<0.05)。实验组并发症总发生率显著低于对照组(P<0.05)。结论相比于同期去皮神经游离ALTF重建,带皮神经游离ALTF重建对舌癌患者的疗效确切,能降低并发症发生率,有效提高患者生活质量。 展开更多
关键词 带皮神经 失皮神经 股前外侧皮瓣 同期重建 舌癌根治术 并发症
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面向电力作业无人机的位姿估计与目标感知方法 被引量:1
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作者 卓浩泽 张驰 +4 位作者 李泰霖 杨忠 蒋圣超 朱泽堃 王斌 《南方电网技术》 北大核心 2025年第7期140-149,共10页
高压架空输电线路作为电力传输的载体,是电力系统稳定运行的重要保障。因此,尽早发现输电线路异常表象(如异物、断股等)并及时实施维保作业显得格外重要。在此背景下,智能电力作业机器人的大力推广将有助于确保电网系统的安全、高效且... 高压架空输电线路作为电力传输的载体,是电力系统稳定运行的重要保障。因此,尽早发现输电线路异常表象(如异物、断股等)并及时实施维保作业显得格外重要。在此背景下,智能电力作业机器人的大力推广将有助于确保电网系统的安全、高效且经济地运行。针对现有电力作业无人机模式识别与自动跟踪能力弱、视觉里程计鲁棒性较差的问题,提出了一种基于点线特征融合的无人机位姿估计方法,开发了一套完整的无人机目标检测与追踪系统。相比于现有的无人机环境感知方案,所提出的目标追踪算法能够高效地提取出红外图像中的点特征和线特征,以较低的功耗实现小型多旋翼无人机在输电线路场景下的目标检测与自动追踪功能。 展开更多
关键词 电网安全运维 输电线路巡检 电力作业无人机 智能机器人 同步定位与建图
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Bernstein型算子在积分Wiener空间同时逼近的平均误差
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作者 包淑华 吴美华 《呼伦贝尔学院学报》 2025年第5期103-110,共8页
文中的Bernstein型算子是用多个相邻点函数值的平均值去代替单点函数值而构造的算子。构造过程中利用Wiener空间的基本性质,借助一些常用不等式及多变量分块求和的技巧,在r重积分Wiener空间上推算同时逼近的误差估计。结论表明,该算子... 文中的Bernstein型算子是用多个相邻点函数值的平均值去代替单点函数值而构造的算子。构造过程中利用Wiener空间的基本性质,借助一些常用不等式及多变量分块求和的技巧,在r重积分Wiener空间上推算同时逼近的误差估计。结论表明,该算子在上述测度空间上的逼近误差与经典Bernstein算子相应的平均逼近误差同阶。 展开更多
关键词 BERNSTEIN型算子 积分Wiener空间 同时逼近 平均误差
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Intracavity configuration for tuning and obtaining simultaneous dual-wavelength operation from CW Nd:YAG laser 被引量:1
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作者 Alireza Khorsandi Saeed Ghavami Sabouri 《Chinese Optics Letters》 SCIE EI CAS CSCD 2011年第7期55-58,共4页
In this letter, a thin slab of glass is used as Fabry-Perot etalon inside a cavity of a continuous wave (CW) Nd:YAG laser to change the behavior of its output longitudinal modes. The slab etalon is used as tuning e... In this letter, a thin slab of glass is used as Fabry-Perot etalon inside a cavity of a continuous wave (CW) Nd:YAG laser to change the behavior of its output longitudinal modes. The slab etalon is used as tuning element when it turns around the laser cavity axis. Two simultaneous longitudinal modes with a relatively wide tuning range from 5.83 MHz to 0,02 THz are obtained when the Nd:YAG laser is operated at moderate output power of about 120 roW. The mode structure of this configuration is modeled and simulated. Computer-generated diagrams are also presented schematically and compared with the experimental results. 展开更多
关键词 YAG Intracavity configuration for tuning and obtaining simultaneous dual-wavelength operation from CW Nd ND CW
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