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Influence of yawing force frequency on angular motion and ballistic characteristics of a dual-spin projectile

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Defence Technology（防务技术） 2016年第2期12卷 124-128页

作者： yu WANG jie CHENG ji-yan yu Xiao-ming WANG 202 School of Mechanical Engineering Nanjing University of Science and Technology Nanjing Jiangsu Province China

A roll-decoupled course correction fuze with canards can improve the hit accuracy of conventional unguided ammunitions. The fuze increases accuracy by reducing the effect of angular and translational motion produced by the cyclical yawing forces applied on the projectile. In order to investigate the influence of yawing forces on angular motion, a theoretical solution of the total yaw angle function with the cyclical yawing forces is deduced utilizing the 7 degrees of freedom(7-DOF) model designed for this calculation. Furthermore, a detailed simulation is carried out to determine the influence rules of yawing force on angular motion. The calculated results illustrate that, when the rotational speed of the forward part is close to the initial turning rate, the total yaw angle increases and the flight range decreases sharply. Moreover, a yawing force at an appropriate frequency is able to correct the gun azimuth and elevation perturbation to some extent.

关键词：偏航角角运动弹道特性弹丸频率双自旋弹道修正引信 6-DOF

Ground target localization algorithm for semi-active laser terminalcorrection projectile

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Defence Technology（防务技术） 2016年第3期12卷 234-241页

作者： Xing-long LI Wen-jin YAO Li-kun ZHU Xiao-ming WANG ji-yan yu School of Mechanical Engineering Nanjing University of Science and Technology Nanjing China Institute of Chemical Materials of CAEP Mianyang Sichuan 621900 China

A target localization algorithm,which uses the measurement information from onboard GPS and onboard laser detector to acquire the target position,is proposed to obtain the accurate position of ground target in real time in the trajectory correction process of semi-active laser terminal correction projectile.A target localization model is established according to projectile position,attitude and line-of-sight *** effects of measurement errors of projectile position,attitude and line-of-sight angle on localization accuracy at different quadrant elevation angles are analyzed through Monte-Carlo *** simulation results show that the measurement error of line-of-sight angle has the largest influence on the localization *** localization accuracy decreases with the increase in quadrant elevation ***,the maximum localization accuracy is less than 7 *** proposed algorithm meets the accuracy and real-time requirements of target localization.

关键词： Semi-active laser guidance Terminal correction projectile Target localization Localization accuracy

Long-term results of small-diameter proximal splenorenal venous shunt:A retrospective study

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World Journal of Gastroenterology 2011年第29期17卷 3453-3458页

作者： Hao Chen Wei-Ping yang ji-Qi yan Qin-yu Li Di Ma Hong-Wei Li Department of Surgery Ruijin HospitalShanghai Jiaotong University School of MedicineShanghai 200025China

AIM:To investigate recurrent variceal hemorrhage and long-term survival rates of patients treated with partial proximal splenorenal venous ***:Patients with variceal hemorrhage who were treated with small-diameter proximal splenorenal venous shunt in Ruijin Hospital between 1996 and 2009 were included in this *** diameter was determined before operation using Duplex Doppler ***-operative and long-term results in term of rehemorrhage,encephalopathy and mortality were followed ***:Ninety-eight patients with Child A and B variceal hemorrhage received small-diameter proximal splenorenal venous shunt with a diameter of 7-10 *** operation,the patients’mean free portal pressure (P<0.01)and the flow rate of main portal vein(P< 0.01)decreased significantly compared with that before *** rates of rebleeding and mortality were 6.12%(6 cases)and 2.04%(2 cases),***-one patients were followed up for 7 mo-14 years (median,48.57 mo).Long-term rates of rehemorrhage and encephalopathy were 4.40%(4 cases)and 3.30% (3 cases),*** patients(14.29%)died mainly due to progressive hepatic *** ten-year survival rates were 82.12%and 71.24%,***:Small-diameter proximal splenorenal venous shunt affords protection against variceal rehemorrhage with a low occurrence of encephalopathy in patients with normal liver function.

关键词： Partial portacaval shunt Hemorrhage Esophageal varices Shunt diameter Encephalopathy

BORDER PORT MANZHOULI:URBAN FUNCTION AND SPACE DEVELOPMENT

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Chinese Geographical Science 2002年第4期12卷 315-320页

作者： ZHANG Ping-yu,MA yan-ji,yu Zhen-han(Changchun Institute of Geography,t he Chinese Academy of Sciences,Changchun 130012,P.R.China) Changchun Institute of Geography the Chinese Academy of Sciences Changchun P. R. China

Manzhouli is the largest land port city on the Sino-Russia border,transit cargo through the land port amount -ed to 5.95million tons,transit tour ists were 304500in *** stands at the joint place of China,Mongolia an d Russi-a,faces to Siberia area of Russia,re ceives direct support from the North east China and Bohai Sea Rim Area,and possess-es priorities in geographical location,land port infrastructure,wate r resources,coal resources,touris t resources and great potentiality in economic coop eration with *** future urban function is a key port on the First Eurasia Continen-tal *** Port will keep its first place between China and Russia land transport,and it is forecasted that the transit amount through Manzhouli Port will go up to 10million tons in 2005and 20million tons in *** will be construct-ed to be a trade center of the peripheral area extending to Russia and Mongolia,a key export-oriented processing industri-al zone supported by industries such as export processing industries,export agriculture,trade services,t echnology trad-ing and the other service *** keeps being a well-known touring city for trade,shopping,sightseeing,vocation,local food,recreation and cultural *** build Manzhouli Export Pr ocessing Industry Zone will improve city econom-ic structure,and the main sectors are organic food processing,livestock products processing,garment and f urniture ***,Manzhouli Export Pro cessing Industry Zone will eventually be upgraded to be a border free trad e *** city functional transition will inevitably affect urban spatial restructure and its *** city space transforma-tion will develop as such:one develo pment axis of No.301highway paralle ling with Bin -Zhou(Harbin -Manzhouli)rail-way which cuts through central part o f Manzhouli City,and links Zhalainuoer District with central city;thre e urban units including central city,Zhalainuoer District and Manzhouli Interchange Trade Zone;coh

关键词： manzhouli land port city development sino-russia border trade

Evaluating the efficacy of immunotherapy in gastric cancer:Insights from immune checkpoint inhibitors

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World Journal of Gastroenterology 2024年第32期30卷 3726-3729页

作者： yu-Nuo yang Li-Sheng Wang yan-Qi Dang Guang ji Institute of Digestive Diseases Longhua HospitalChina-Canada Center of Research for Digestive DiseasesShanghai University of Traditional Chinese MedicineShanghai 200032China Department of Biochemistry University of OttawaOttawa K1H 8M5ONCanada

The emergence of immunotherapy,particularly immune checkpoint inhibitors(ICIs),represents a groundbreaking approach to treating gastric cancer(GC).However,the prognosis of GC patients receiving ICI treatment is influenced by various *** manuscript identified sarcopenia and myosteatosis as independent prognostic factors impacting the outcomes of GC patients treated with ***,this study introduced a visual predictive model to estimate the prognosis of GC *** confirmed by further studies,this observation could provide valuable insights to propel the advancement of personalized clinical medicine and the integration of precision medicine practices.

关键词： Gastric cancer Immune checkpoint inhibitors Sarcopenia Myosteatosis Prediction model

Equivalent linear model for seismic damage evaluation of single-degree-of-freedom systems representing reinforced concrete structures considering cyclic degradation behavior

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 637-648页

作者： Lulu yan Ding-Hao yu Research Center for Geotechnical and Structural Engineering Technology of Liaoning Province Dalian UniversityDalian116622China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

In this study,a novel equivalent damping ratio model that is suitable for reinforced concrete(RC)structures considering cyclic degradation behavior is developed,and a new equivalent linearization analysis method for implementing the proposed equivalent damping ratio model for use in seismic damage evaluation is *** this end,Ibarra’s peak-oriented model,which incorporates an energy-based degradation rule,is selected for representing hysteretic behavior of RC structure,and the optimized equivalent damping for predicting the maximum displacement response is presented by using the empirical method,in which the effect of cyclic degradation is ***,the relationship between the hysteretic energy dissipation of the inelastic system and the elastic strain energy of the equivalent linear system is established so that the proposed equivalent linear system can be directly integrated with the Park-Ang seismic model to implement seismic damage *** to the simplicity of the equivalent linearization method,the proposed method provides an efficient and reliable way of obtaining comprehensive insight into the seismic performance of RC *** verification demonstrates the validity of the proposed method.

关键词： degrading system equivalent linear system equivalent damping seismic damage RC structures

Sustainable and practical semi-heterogeneous photosynthesis of 5-amino-1,2,4-thiadiazoles over WS_(2)/TEMPO

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Chinese Chemical Letters 2024年第8期35卷 250-253页

作者： jia-Cheng Hou Hong-Tao ji yu-Han Lu jia-Sheng Wang Yao-Dan Xu yan-yan Zeng Wei-Min He School of Chemistry and Chemical Engineering University of South ChinaHengyang 421001China

An eco-friendly and practical method for the clean preparation of 5-amino-1,2,4-thiadiazoles was *** WS_(2)as the semiconductor photocatalyst,both TEMPO and O_(2)(in air)as the redox catalysts,a variety of thiadiazoles were semi-heterogeneously formed in high to quantitative yields and could be easily collected by CPME extraction and ***,the catalytic system can be reusable for at least 5 reaction runs.

关键词： Green chemistry Thiadiazoles Heterogeneous catalyst Redox catalyst Extraction

Review of Iron-Based Catalysts for Carbon Dioxide Fischer-Tropsch Synthesis

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Transactions of Tianjin University 2024年第2期30卷 178-197页

作者： ji-yue jia yu-Ling Shan Yong-Xiao Tuo Hao yan Xiang Feng De Chen State Key Laboratory of Heavy Oil Processing China University of PetroleumQingdao 266580China College of Chemical Engineering Qingdao University of Science and TechnologyQingdao 266042China Department of Chemical Engineering Norwegian University of Science and Technology7491 TrondheimNorway

Capturing and utilizing CO_(2)from the production process is the key to solving the excessive CO_(2)emission problem. CO_(2)hydrogenation with green hydrogen to produce olefins is an effective and promising way to utilize CO_(2)and produce valuable chemicals. The olefins can be produced by CO_(2)hydrogenation through two routes, i.e., CO_(2)-FTS (carbon dioxide Fischer- Tropsch synthesis) and MeOH (methanol-mediated), among which CO_(2)-FTS has significant advantages over MeOH in practical applications due to its relatively high CO_(2)conversion and low energy consumption potentials. However, the CO_(2)-FTS faces challenges of difficult CO_(2)activation and low olefins selectivity. Iron-based catalysts are promising for CO_(2)-FTS due to their dual functionality of catalyzing RWGS and CO-FTS reactions. This review summarizes the recent progress on iron-based catalysts for CO_(2)hydrogenation via the FTS route and analyzes the catalyst optimization from the perspectives of additives, active sites, and reaction mechanisms. Furthermore, we also outline principles and challenges for rational design of high-performance CO_(2)-FTS catalysts.

关键词： CO_(2)hydrogenation Olefins CO_(2)-FTS Iron-based catalysts

Double-nylon purse-string suture in closing postoperative wounds following endoscopic resection of large(≥3 cm)gastric submucosal tumors

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World Journal of Gastroenterology 2024年第9期30卷 1143-1153页

作者： Shan-Shan Wang Meng-Yao ji Xu Huang yan-Xia Li Shi-jie yu yu Zhao Lei Shen Department of Gastroenterology Renmin Hospital of Wuhan UniversityWuhan 430000Hubei provinceChina

BACKGROUND Endoscopic full-thickness resection(EFTR)of gastric submucosal tumors(SMTs)is safe and effective;however,postoperative wound management is equally *** on suturing following EFTR for large(≥3 cm)SMTs is scarce and *** To evaluate the efficacy and clinical value of double-nylon purse-string suture in closing postoperative wounds following EFTR of large(≥3 cm)*** We retrospectively analyzed the data of 85 patients with gastric SMTs in the fundus of the stomach or in the lesser curvature of the gastric body whose wounds were treated with double-nylon purse-string sutures after successful tumor resection at the Endoscopy Center of Renmin Hospital of Wuhan *** operative,postoperative,and follow-up conditions of the patients were *** All tumors were completely resected using EFTR.36(42.35%)patients had tumors located in the fundus of the stomach,and 49(57.65%)had tumors located in the body of the *** patients underwent suturing with double-nylon sutures after EFTR without laparoscopic assistance or further surgical *** fever and stomach pain were reported in 13(15.29%)and 14(16.47%)patients,*** serious adverse events occurred during the intraoperative or postoperative periods.A postoperative review of all patients revealed no residual or recurrent *** Double-nylon purse-string sutures can be used to successfully close wounds that cannot be completely closed with a single nylon suture,especially for large(≥3 cm)EFTR wounds in SMTs.

关键词： Endoscopic full-thickness resection Purse-string suture Postoperative wounds Submucosal tumors