Passively Q-Switched Nd,Cr:YAG Laser Simultaneous Dual-Wavelength Operation at 946 nm and 1.3μm

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.

CFD Based Simulation of LNG Release during Bunkering and Cargo Loading/Unloading Simultaneous Operations of a Containership

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.

Simultaneous operation for cardiac disease and gastrointestinal malignancy

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.

Simultaneous Approximation by Baskakov-Durrmeyer Operator

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.

EQUIVALENT THEOREMS ON SIMULTANEOUS APPROXIMATION BY COMBINATIONS OF BERNSTEIN OPERATORES

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.

ON SHAPE-PRESERVING PROPERTIES AND SIMULTANEOUS APPROXIMATION OF STANCU OPERATOR

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.

Simultaneous Approximation for Szsz-Mirakian-Stancu-Durrmeyer Operators

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.

SIMULTANEOUS APPROXIMATION BY BERNSTEIN-SIKKEMA OPERATORS

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.

EQUIVALENT THEOREMS ON SIMULTANEOUS APPROXIMATION BY COMBINATIONSOF GAMMA OPERATORS

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.

EQUIVALENCE THEOREM ON WEIGHTED SIMULTANEOUS L-APPROXIMATION BY MEANS OF SZASZ-KANTOROVICH OPERATORS AND BASKAKOV-KANTOROVICH OPERATORS

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.

A Comparison of Arithmetic Operations for Dynamic Process Optimization Approach

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.

POINTWISE SIMULTANEOUS APPROXIMATION BY LEFT GAMMA QUASI-INTERPOLANTS

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.

APPROXIMATION BY COMPLEX SZSZ-DURRMEYER OPERATORS IN COMPACT DISKS

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.

Intracavity configuration for tuning and obtaining simultaneous dual-wavelength operation from CW Nd:YAG laser

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.

Approximation by Complex Baskakov-Szsz-Durrmeyer Operators in Compact Disks

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,∞）.

船舶采用LNG加注与装卸货同步作业风险评估研究

为了有效评估沿海港口船舶采用LNG加注与装卸货同步作业的潜在风险和相应缓解措施,本文选定上海洋山港二期码头为作业地点,以一艘20 000m3LNG加注船为14 800TEU双燃料集装箱船实施LNG加注并同时进行装卸货作业为研究对象,基于国内外广泛认可的风险评估方法进行危险源辨识和失效概率分析,拟定了4个LNG泄漏场景,采用三维计算流体力学软件FLACS分析了LNG泄漏后的可燃气体对两船的波及范围,同时考虑到集装箱装卸货对LNG加注船及作业的影响,提出了LNG加注与装卸货同步作业的限制区域、警戒区域及安全保障措施建议。

Simultaneous Approximation by Modified Bernstein-Durrmeyer Operators *

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.

滑翔制导炮弹多炮齐射协同弹道规划与协作范围确定方法

针对滑翔制导炮弹多炮齐射打击固定目标的协同攻击场景,为充分发挥整体控制能力,增强打击效果,研究着眼于弹群的协同方案弹道规划问题。首先,考虑到攻击不同距离目标时飞行方案的侧重点与弹道特性差异,为滑翔制导炮弹进行战区划分,并在此基础上建立寻优指标因战区而异的全弹道协同规划模型。其次,针对实战中的战斗队形配置问题,提出一种简单通用的协作范围确定方法。随后,针对现有协同方式在处理多阶段规划问题时存在的适用性或最优性方面的局限,提出一种双层自适应协同策略。最后,分析特殊作战任务引入的额外约束条件对战区划分与协作范围的影响。仿真结果表明,所提方法可以简捷有效地确定可行工况,辅助战斗队形的配置;同时,相比于传统的分布式策略,在所提的协同策略作用下,不同战区内的方案弹道均具有优越性。

一期双侧膝关节内侧单间室置换的安全性研究

目的探讨一期双侧膝关节内侧单间室置换(OB-UKA)的安全性。方法回顾性分析2021年1月—2023年1月在南京鼓楼医院进行OB-UKA手术的35例膝关节骨性关节炎患者的临床资料,并在同期行单侧膝关节内侧单间室置换(UKA)和单侧全膝关节置换(TKA)的患者中选择年龄、性别匹配者各35例作为对照,比较3组患者手术相关指标(手术时间、总失血量、住院时间)、营养状态[血红蛋白(Hb)、白蛋白(ALB)]、炎症指标[白细胞计数(WBC)、C反应蛋白(CRP)]、疼痛程度、膝关节功能评分及并发症。结果术前3组间一般资料的差异无统计学意义(P>0.05)。OB-UKA组手术时间较UKA组和TKA组长(P<0.05),总失血量与TKA组比较差异无统计学意义(P>0.05),明显高于UKA组(P<0.05);术后OB-UKA组和UKA组Hb、ALB比较差异无统计学意义(P>0.05);OB-UKA组和TKA组术后WBC、CRP比较差异无统计学意义(P>0.05);OB-UKA组术后视觉模拟评分(VAS)与UKA组比较差异无统计学意义(P>0.05),明显低于TKA组(P<0.05);OB-UKA组美国特种外科医院膝关节功能评分(HSS)与UKA组比较差异无统计学意义(P>0.05),但明显高于TKA组(P<0.05);UKA组、OB-UKA组并发症发生率均为2.9%,低于TKA组并发症发生率(5.7%)(P<0.05)。结论OB-UKA与UKA相比,手术时间延长,失血量增加,但术后营养相关指标与UKA水平相似,疼痛程度较低,膝关节功能评分与UKA相当。此外,OB-UKA术后炎症相关指标与TKA水平相似,围术期并发症发生率低于TKA,且与UKA相似。OB-UKA可以作为双膝内侧间室退变患者的安全有效的首选术式。

基于多传感器融合SLAM的ROS服务机器人研究

为提升自主导航精度,使用Jetson Nano控制器,采用同步定位与地图构建和路径规划算法,融合轮式里程计、激光雷达和惯性测量单元等多传感器信息,实现精确的单点和多点自主导航。采用机器人操作系统搭建自主导航框架,使用基于图优化的cartographer算法实现环境地图构建与机器人位姿估计,采用A*算法作为全局路径规划算法,同时利用基于g2o优化的TEB算法实现环境突变时的局部路径规划。实验结果表明,基于图优化的cartographer算法建图效果优于常见的基于粒子滤波的Gmapping算法。基于g2o优化的TEB算法可避免动态窗口算法在局部路径规划中机器人被挟持的情况,提升智能机器人地图构建和路径规划的准确性。