Hybrid Operator and Strengthened Diversity Improving for Multimodal Multi-Objective Optimization

Multimodal multi-objective optimization problems(MMOPs)contain multiple equivalent Pareto subsets(PSs)corresponding to a single Pareto front(PF),resulting in difficulty in maintaining promising diversities in both objective and decision spaces to find these PSs.Widely used to solve MMOPs,evolutionary algorithms mainly consist of evolutionary operators that generate new solutions and fitness evaluations of the solutions.To enhance performance in solving MMOPs,this paper proposes a multimodal multi-objective optimization evolutionary algorithm based on a hybrid operator and strengthened diversity improving.Specifically,a hybrid operator mechanism is devised to ensure the exploration of the decision space in the early stage and approximation to the optima in the latter stage.Moreover,an elitist-assisted differential evolution mechanism is designed for the early exploration stage.In addition,a new fitness function is proposed and used in environmental and mating selections to simultaneously evaluate diversities for PF and PSs.Experimental studies on 11 widely used benchmark instances from a test suite verify the superiority or at least competitiveness of the proposed methods compared to five state-of-the-art algorithms tailored for MMOPs.

Effect of Wave Accessibility on Lower Hybrid Wave Current Drive in Experimental Advanced Superconductor Tokamak with H-Mode Operation

The effect of the wave accessibility condition on the lower hybrid cm＇rent drive in the experimental advanced superconductor Tokamak （EAST） plasma with H-mode operation is studied. Based on a simplified model, a mode conversion layer of the lower hybrid wave between the fast wave branch and the slow wave branch is proved to exist in the plasma periphery for typical EAST H-mode parameters. Under the framework of the lower hybrid wave simulation code （LSC）, the wave ray trajectory and the associated current drive are calculated numerically. The results show that the wave accessibility condition plays an important role on the lower hybrid current drive in EAST plasma. For wave rays with parallel refractive index n｜｜= 2.1 or n｜｜ = 2.5 launched from the outside midplane, the wave rays may penetrate the core plasma due to the toroida] geometry effect, while numerous reflections of the wave ray trajectories in the plasma periphery occur. However, low current drive efficiency is obtained. Meanwhile, the wave accessibility condition is improved if a higher confined magnetic field is applied. The simulation results show that for plasma parameters under present EAST H-mode operation, a significant lower hybrid wave current drive could be obtained for the wave spectrum with peak value n｜｜ = 2.1 if a toroidal magnetic field BT =2.5 T is applied.

Optimal scheduling of zero-carbon park considering variational characteristics of hydrogen energy storage systems

Zero-carbon parks have broad prospects in carbon neutralization.As an energy hub,hydrogen energy storage plays an important role in zero-carbon parks.However,the nonlinear characteristics of hydrogen energy storage systems(HESSs)have a significant impact on the system economy.Therefore,considering the variable working condition characteristics of HESSs,a hybrid operation method is proposed for HESS,to support the efficient and economic operation of zero-carbon parks,By analyzing the operating principle of a zero-carbon park with HESS,the system structure framework and variable condition linearization model of the equipment in HESS are established.Moreover,considering the energy output characteristics of hydrogen energy storage equipment under variable working conditions,a multimodule hybrid operation strategy is proposed for electrolytic and fuel cells,effectively meeting the thermoelectric load demand of zero-carbon parks in different scenarios.Finally,the economy of the proposed hybrid operation strategy was verified in typical scenarios,using a zero-carbon park embedded with a HESS.

Some interval-valued intuitionistic uncertain linguistic hybrid Shapley operators

Two interval-valued intuitionistic uncertain linguistic hybrid operators cal ed the induced interval-valued intuitionistic uncertain linguistic hybrid Shapley averaging （I-IIULHSA） operator and the induced interval-valued intuitionistic uncertain linguistic hybrid Shapley geometric （I-IIULHSG） operator are defined. These operators not only reflect the importance of elements and their ordered positions, but also consider the correlations among elements and their ordered positions. Since the fuzzy measures are defined on the power set, it makes the problem exponentially complex. In order to simplify the complexity of solving a fuzzy measure, we further define the induced interval-valued intuitionistic uncertain linguistic hybrid λ-Shapley averaging （I-IIULHλSA） operator and the induced interval-valued intuitionistic uncertain linguistic hybrid λ-Shapley geometric （I-IIULHλSG） operator. Moreover, an approach for multi-attribute group decision making under the interval-valued intuitionistic uncertain linguistic environment is developed. Finally, a numerical example is provided to verify the developed procedure and demonstrate its practicality and feasibility.

Hybrid Efficient Convolution Operators for Visual Tracking

Visual tracking is a classical computer vision problem with many applications.Efficient convolution operators(ECO)is one of the most outstanding visual tracking algorithms in recent years,it has shown great performance using discriminative correlation filter(DCF)together with HOG,color maps and VGGNet features.Inspired by new deep learning models,this paper propose a hybrid efficient convolution operators integrating fully convolution network(FCN)and residual network(ResNet)for visual tracking,where FCN and ResNet are introduced in our proposed method to segment the objects from backgrounds and extract hierarchical feature maps of objects,respectively.Compared with the traditional VGGNet,our approach has higher accuracy for dealing with the issues of segmentation and image size.The experiments show that our approach would obtain better performance than ECO in terms of precision plot and success rate plot on OTB-2013 and UAV123 datasets.

Combined Endovascular and Surgical Treatment for Brain Arteriovenous Malformations in Biplanar Hybrid Operating Room

Objective Combined surgical and endovascular treatment for vascular disorders has become prevalent in recent years.However,reports on one-session hybrid surgery for arteriovenous malformations(AVMs)are relatively rare.The safety and efficiency of combined treatment for brain AVMs were analyzed in biplanar hybrid operating room(OR)at one stage.Methods We retrospectively analyzed 20 patients with AVMs undergoing combined surgical and endovascular treatment from October 2015 to June 2018.The data for resection rate,microcatheter adhesion,surgical position and postoperative outcomes were analyzed.Total resection or near-total resection was achieved in all cases.Results A total of 13 patients were under combined endovascular and surgical procedures,and 7 experienced surgery with intraoperative digital subtraction angiography.Sitting position was applied in 3 of them;2 niduses in cerebellum,and 1 in parietal lobe.Compared with admission modified Rankin Scale(mRS)in all patients,postoperative 12-month mRS showed a significant decline.Besides,3 patients experienced microcatheter adhesion after endovascular embolization,thereafter underwent surgical adhesion removal while nidus resection was done.Conclusion Combined endovascular and surgical modality in a hybrid OR at one stage provides a safe strategy for the treatment of AVMs.The biplanar hybrid neurointerventional suite is endowed with unconstrained operating angle which enables combined endovascular and surgical treatment in sitting position.It also reduces the risk of microcatheter adhesion,which enables interventional radiologists to perform aggressively.

Transileocolic endovascular treatment by a hybrid approach for severe acute portal vein thrombosis with bowel necrosis:Two case reports

BACKGROUND Acute portal vein thrombosis(PVT)with bowel necrosis is a fatal condition with a 50%-75%mortality rate.This report describes the successful endovascular treatment(EVT)of two patients with severe PVT.CASE SUMMARY The first patient was a 22-year-old man who presented with abdominal pain lasting 3 d.The second patient was a 48-year-old man who presented with acute abdominal pain.Following contrast-enhanced computed tomography,both patients were diagnosed with massive PVT extending to the splenic and superior mesenteric veins.Hybrid treatment(simultaneous necrotic bowel resection and EVT)was performed in a hybrid operating room(OR).EVTs,including aspiration thrombectomy,catheter-directed thrombolysis(CDT),and continuous CDT,were performed via the ileocolic vein under laparotomy.The portal veins were patent 4 and 6 mo posttreatment in the 22-year-old and 48-year-old patients,respectively.CONCLUSION Hybrid necrotic bowel resection and transileocolic EVT performed in a hybrid OR is effective and safe.

Application of hybrid operating rooms for clipping large or giant intracranial carotid-ophthalmic aneurysms

BACKGROUND A hybrid operating room(Hybrid-OR)is a surgical theatre that combines a conventional operating room with advanced medical imaging devices.There are still plenty of limitations when endovascular treatment or microsurgical treatment is used individually to treat large or giant carotid-ophthalmic aneurysms.AIM To explore and summarize the technical features and effectiveness of the application of a Hybrid-OR in managing major intracranial carotid-ophthalmic aneurysms.METHODS The Department of Neurosurgery treated 12 cases of large or giant intracranial carotid-ophthalmic aneurysms between March 2013 and December 2019 in a Hybrid-OR.All cases were treated with clipping and parent vessel reconstruction.RESULTS With the assistance of the Hybrid-OR,the rate of incomplete intraoperative aneurysm clipping decreased from 25%(3/12)to 0%,while the rate of vessel stenosis decreased from 16.7%(2/12)to 8.35%(1/12).In terms of thromboembolic events,ischemic infarction complication occurred in only one patient,and none of the patients experienced embolic infarction complications.All 12 patients were followed for an average of 3 years,and no aneurysms recurred.The postoperative recovery was evaluated with the modified Rankin Scale(mRS):11 patients showed no symptoms(mRS=0),1 patient showed slight disability(mRS 1-2),and none of the patients had severe disability(mRS=5)or died(mRS=6).CONCLUSION The Hybrid-OR provides new ideas for the surgical clipping of large or giant intracranial carotid-ophthalmic aneurysms and decreases the rate of intraoperative vessel stenosis and unsuccessful clipping.

Surgical Treatment of Aortic Aneurysm and Aortic Dissection:A Retrospective Analysis of 122 Cases

The study summarizes the clinical experience of surgical treatments of various types of thoracic aneurysm and aortic dissection. Clinical data of 122 patients with thoracic aneurysm and aortic dissection during July 2005 to July 2008 were retrospectively analyzed. The elective operations were performed in 107 patients while emergency surgery was done in 15 cases. Different surgical strategies were employed on the basis of diseased region, including simple ascending aortic replacement （n=3）, aortic root replacement （n=43）, hemi-arch replacement/total arch replacement ＋ elephant trunk technique （n=32）, thoracic/thoracoabdominal aortic replacement （n=8） and endovascular repair （n=36）. In this series, there is 4 cases of perioperative death due to massive cerebral hemorrhage （n=1）, respiratory failure （n=1） and multiple organ dysfunction syndrome （MODS） （n=2）. Three cases developed post-operative massive cerebral infarction and the relatives of the patients abandoned treatment. Instant success rate of endovascular repair was 100%. The intimal rupture was sealed. Blood flow was unobstructed in true lumen and no false lumen was visualized. It was concluded that aggressive surgery should be considered in the patients with thoracic aneurysm and aortic dissection. Surgical procedures should vary with the location and the nature of the lesions.

空间快速响应航天器轨道/弹道一体化规划

以空间应急响应任务为背景,采用轨道/弹道一体化规划设计方法,实现空间快速响应航天器全程飞行轨迹规划。在分析弹道设计参数对轨道参数影响性的基础上,将弹道规划分为程序角参数设计和发射诸元参数设计,采用改进的粒子群算法和牛顿迭代法进行混合优化求解。算例表明,使用混合优化求解方法收敛速度快,迭代次数少,易于工程实现,能满足一体化任务规划的快速性要求,可为空间快速响应航天器设计提供理论参考。

Lanchester equation for cognitive domain using hesitant fuzzy linguistic terms sets

Intelligent wars can take place not only in the physical domain and information domain but also in the cognitive domain.The cognitive domain will become the key domain to win in the future intelligent war.A Lanchester equation considering cognitive domain is proposed to fit the development tendency intelligent wars in this paper.One party is considered to obtain the exponential enhancement advantage on combat forces in combat if it can gain an advantage in the cognitive domain over the other party according to the systemic advantage function.The operational effectiveness of the cognitive domain in war is considered to consist of a series of indicators.Hesitant fuzzy sets and linguistic term sets are powerful tools when evaluating indicators,hence the indicators are scored by experts using hesitant fuzzy linguistic terms sets here.A unique hesitant fuzzy hybrid arithmetical averaging operator is used to aggregate the evaluation.

A New Hesitant Fuzzy Multiple Attribute Decision Making Method with Unknown Weight Information

In this paper, we focus on a new approach based on new generalized hesitant fuzzy hybrid weighted aggregation operators, in which the evaluation information provided by decision makers is expressed in hesitant fuzzy elements (HFEs) and the information about attribute weights and aggregation-associated vector is unknown. More explicitly, some new generalized hesitant fuzzy hybrid weighted aggregation operators are proposed, such as the new generalized hesitant fuzzy hybrid weighted averaging (NGHFHWA) operator and the new generalized hesitant fuzzy hybrid weighted geometric (NGHFHWG) operator. Some desirable properties and the relationships between them are discussed. Then, a new algorithm for hesitant fuzzy multi-attribute decision making (HF-MADM) problems with unknown weight information is introduced. Further, a practical example is used to illustrate the detailed implementation process of the proposed approach. A sensitivity analysis of the decision results is analyzed with different parameters. Finally, comparative studies are given to verify the advantages of our method.

Hybrid Krill Herd Algorithm with Vortex Search for Global Numerical Optimization

In order to solve the problem that the krill herd(KH)algorithm is premature due to the decrease of population diversity,a new hybrid vortex search KH(VSKH)algorithm has been developed to deal with the global optimization problem.The improvement is that a new hybrid vortex search(HVS)operator is added into the updating process of the krill for the purpose of dealing with optimization problems more efficiently.Using 20 benchmark functions for comparison experiments,the results show that the VSKH algorithm has higher accuracy.

Timetable optimization for single bus line based on hybrid vehicle size model

This study proposes a flexible timetable optimization method based on hybrid vehicle size model to tackle the bus demand fluctuations in transit operation. Three different models for hybrid vehicle, large vehicle and small vehicle are built in this study, respectively. With the operation data of Shanghai Transit Route 55 at peak and off-peak hours, a heuristic algorithm was proposed to solve the problem. The results indicate that the hybrid vehicle size model excels the other two modes both in the total time and total cost. The study verifies the rationality of the strategy of hybrid vehicle size model and highlights the importance of the adaptive vehicle size in dealing with the bus demand fluctuation. The main innovation of the study is that unlike traditional timetables, the arrangement of the scheduling interval and the corresponding bus type or size are both involved in the timetable of hybrid vehicle size bus mode, which will be more effective to solve the problem of passenger demand fluctuation. Findings from this research would provide a new perspective to improve the level of regular bus service.