《操作系统原理》教学研究

《操作系统原理》作为计算机专业的一门专业核心课程,其重要性不言而喻。但是该课程内容庞杂、涉及面广、概念抽象、实践性强,内容不易理解,难于掌握。本着"因材施教"的根本原则,以调动学生学习操作系统原理的积极性、提高学生的分析能力和解决问题的能力为目标,从教学目的、教学内容、教学方法等几个方面对《操作系统原理》课程的教学进行了研究和探讨。

浅谈科学计算可视化及其应用

近年来,随着科学技术的迅猛发展,待处理的数据量越来越大,来自超级计算机、卫星、宇宙飞船、CT扫描仪、核磁共振仪以及地质勘探的数据与日俱增,使科学计算数据的可视化及计算过程的交互干预与引导日益成为迫切需要解决的问题。本文简要介绍了科学计算可视化的重要意义及其目前在社会各个领域的应用。

多媒体教学的误区与矫治

自90年代起,多媒体技术开始在教学中广泛应用,它对于实现最理想的学习环境、改变学习者在学习中的相对被动地位、激发学生的学习兴趣和动机等具有非常重要的作用。但是在多媒体教学中还存在着一些误区,若不处理好这些问题,就可能适得其反。本文就多媒体教学中的一些误区与矫治提出了一些个人见解。

色彩表达在景观建筑设计中的重要性

在景观建筑中的设计过程中,色彩的表达是非常重要的,当人们观看景观建筑物时,建筑设计的色彩搭配会直接影响人们的心理和生理的变化以及对景观建筑的整体影响,合理的色彩搭配可以体现出建筑的主体和设计师想要表达的情感。所以,如何在景观建筑设计中合理的表达出色彩,是值得景观建筑设计师在设计的时候思考的主要问题。本文重点讨论色彩表达在景观建筑设计中的重要性,以及设计师搭配色彩的缺点和不足,来综合分析色彩是如何可以表达出设计师对景观建筑的灵感和内容。

活动断裂带深埋隧洞减震的铰接间距效应

以某穿越区域活动断裂带深埋引水隧洞工程为依托,基于结构与围岩共同作用原理,采用理论与数值计算相结合的方法,研究地震作用下活动断裂带围岩和衬砌的动力响应特征,探讨活动断裂带链式衬砌减震性能的铰接间距效应.结果表明,地震作用下隧洞围岩和衬砌在活动断裂带界面处出现应力集中;断裂带内的围岩和衬砌相较于断裂带外的围岩和衬砌对地震位移的响应更强烈,变形更大.地震作用下,铰接结构显著降低了断裂带内和断裂带界面处衬砌的峰值最大主应力和峰值最大剪力;衬砌内力随铰接间距的减小而降低,但并非铰接间距越短越好,适当间距的铰接结构具有更优的减震性能和更佳的利用效果.

采用双核模型研究超重核合成机制

本文首先介绍了两种描述低能重离子核反应的理论,然后基于这些理论发展了一个描述超重核合成的理论模型,即双核模型(dinuclear system model)。不同于Adamian的处理,本文的模型采用数值求解主方程的方法来描述重离子的熔合过程,重点讨论了熔合过程中主方程的发展演化,选择一维至三维不同的宏观自由度说明重离子熔合机制,为今后进一步发展模型与预言新核素提供理论依据。

不同覆膜处理对水稻生长性状及产量的影响

设置生物降解膜(BE膜)、聚乙烯膜(PE膜)和无覆膜对照3个处理,研究不同地膜覆盖对水稻生长性状和产量的影响。结果表明:不同覆膜处理水稻株高在幼穗发育期至成熟期均比无覆膜对照高,BE膜和PE膜均具有提高水稻株高的效果;水稻有效穗数表现为BE膜>PE膜>无覆膜对照,BE膜处理和PE膜处理较无覆膜对照显著提高水稻有效穗数(P<0.05),分别提高了20%和13%;PE膜处理和BE膜处理较无覆膜对照显著提高水稻产量(P<0.05),分别提高649.85、1 499.40 kg/hm^(2),增幅分别为12.9%、29.8%;BE膜处理较无覆膜对照节水1 410 m^(3)/hm^(2),节水率达到8%;PE膜处理较无覆膜对照节水795 m^(3)/hm^(2),节水率达到5%。因此,以生物降解膜处理更有利于提高水稻产量和水分利用效率。

超重核^(292-310)122同位素链的α衰变和自发裂变的竞争

基于推广的液滴模型(GLDM)理论框架,计算了292-310122同位素链的α衰变和自发裂变的半衰期。计算时的基本输入量为两子核的质量数和电荷数以及反应Q值。GLDM能很好地描述重核和超重核的α衰变和自发裂变过程。计算结果表明,A<308时在同位素链上N=176~184的区域α衰变为主要衰变模式。A>308时在同位素链上自发裂变为主要衰变模式。308122是α衰变和自发裂变的分界点,暗示着N=184为中子幻数。

推广的液滴模型及其应用

简单介绍了近年来在研究重核和超重核衰变性质及熔合反应方面取得的理论成果和面临的挑战,着重阐述推广的液滴模型(GLDM)理论框架及其应用。基于原子核的质量数、质子数以及反应Q值,GLDM考虑了质量和电荷的不对称性、形状演化、亲近势和温度等,很好地描述了重核和超重核的质子放射性、α衰变、重离子放射性、自发裂变的半衰期和重离子熔合反应截面,同时也研究了原子核的粒子(质子、α、重离子)放射性与自发裂变的竞争。

Systematic study of cluster radioactivity within the generalized liquid drop model

Cluster radioactivity is studied within the generalized liquid drop model(GLDM),in which the shell correction energy,pairing energy,and cluster preformation factor are considered.The calculations show significant improvements and can reproduce the experimental data within a factor of 8.04 after considering these physical effects.In addition,the systematic trend of the cluster preformation factors is discussed in terms of the N_(p)N_(n)scheme to study the influence of the valence proton-neutron interaction and shell effect on cluster radioactivity.It is found that log10Pcis linearly related to N_(p)N_(n).This is in agreement with a recent study[L.Qi et al.,Phys.Rev.C 108,014325(2023)],in which log10Pc,obtained using different theoretical models and treatment methods than those used in this study,also had a linear relationship with N_(p)N_(n).Combined with the work by Qi et al.,this study suggests that the linear relationship between log10Pcand N_(p)N_(n)is model-independent and both the shell effect and valence proton-neutron interaction play essential roles in cluster radioactivity.An analytical formula is proposed to calculate the cluster preformation factor based on the N_(p)N_(n)scheme.In addition,the cluster preformation factors and the cluster radioactivity half-lives of some heavy nuclei are predicted,which can provide a reference for future experiments.

Effect of Nucleon Superfluidity and Its Uncertainty on the Neutron Star Cooling

We calculate the cooling curves of superfluid neutron stars with the Brueckner-Hartree-Fock(BHF)equation of state(EOS)by employing the AV18 two body force with a microscopic three body force.The gap energy is calculated within the BCS theory,including in the pairing interaction not only two body force but also three body force.The calculated cooling curves show that the nucleon superfluidity strongly reduces the difference between standard and enhanced cooling.This enables one to explain the majority of observational data by the enhanced cooling of the stars with superfluid cores.The possibility of strong direct Urca processes still cannot be excluded from the cooling analysis.

Basic characteristics of nuclear landscape by improved Weizs?cker-Skyrmetype nuclear mass model

Atomic Mass Evaluation(AME2016) has replenished the latest nuclear binding energy data. Other physical observables, such as the separated energies, decay energies, and the pairing gaps, were evaluated based on the new mass table. An improved Weizs?cker-Skyrme-type(WS-type) nuclear mass model with only 13 parameters was presented, including the correction from two combinatorial radial basis functions(RBFs), where shell and pairing effects are simultaneously dealt with using a Strutinsky-like method. The RBFs code had 2267 updated experimental binding energies as inputs, and their correspondent root-mean square(rms) deviations dropped to 149 keV. For the training of other mass models by RBFs correction, rms deviations are clustered between 100 keV to 200 keV. Compared with other experimental quantities, the rms deviations calculated within the improved WS-type model falls between 100 keV and 250 keV. We extrapolate the binding energies to 12435 nuclei, which covers the ranges 8 ≤ Z ≤ 128 and 8 ≤ N ≤ 251 in the framework of the WS-type model with RBFs correction. Simultaneously, the ground state deformations β_(2,4,6) and all parts in the WS-type mass formula are presented in this paper. Finally, we tabulated all calculated characteristics within the improved formula and linked them to https://github.com/lukeronger/Nuclear Data-LZU: nuclear binding energies, one-nucleon and two-nucleon separation energies(S_(n,p,2n,2p)), and β-decay energies( Q_α and Q_(β-,β+,EC)), and the pairing gap ?_n and ?_p.

探究新课改下初中道德与法治教学的新思路

随着教学改革的不断深化,在基础教育阶段,不再只注重学生学习成绩的优劣,而是更加关注学生综合学习能力以及学科素养的全面发展。其中保证初中道德与法制课堂教学的有效性,正是实现初中学生身心健康、良好发展的重要途径之一。本文立足新课改的视角,提出了初中道德与法制教学的新思路。希望为全面提高初中道德与法制课堂教学水平,起到积极的促进作用。

Diffuseness effect and radial basis function network for optimizing α decay calculations

A radial basis function network(RBFN)approach is adopted for the first time to optimize the calculation of$\alpha$decay half-life in the generalized liquid drop model(GLDM),while concurrently incorporating the surface diffuseness effect.The calculations presented herein agree closely with the experimental half-lives for 68 superheavy nuclei(SHN),achieving a remarkable reduction of 40%in the root-mean-square(rms)deviations of half-lives.Furthermore,using the RBFN method,the half-lives for four SHN isotopes,252-288Rf,272-310Fl,286-316119,and 292-318120,are predicted using the improved GLDM with the diffuseness correction and the decay energies from WS4 and FRDM as inputs.Therefore,we conclude that the diffuseness effect should be embodied in the proximity energy.Moreover,increased application of neural network methods in nuclear reaction studies is encouraged.

Predictions of decay modes for the superheavy nuclei most suitable for synthesis

The competition between α-decay and spontaneous fission of superheavy nuclei（SHN） is investigated by the generalized liquid drop model（GLDM） and the modified Swiatecki＇s formula respectively. The theoretical decay modes are in good agreement with the experimental results. Predictions are made for as-yet unobserved superheavy nuclei. The theoretical calculations show that the nuclei^298 120,^295 119,^290 118,^291 117,^287 117,^294 116,^289 116,^286 116,^285 116,^284 115,^283 115,^283 114,^282 114,^280 113,^276 112,^275 112,^274 112,^273 111,^272 110,^265 109 may be synthesized experimentally in the near future since they not only have relatively large predicted cross sections but can also be identified via α-decay chains.

Research onα-decay for the superheavy nuclei with Z=118-120

The generalized liquid-drop model(GLDM)with the microscopic shell correction from relativistic Hartree-Fock(RHF)calculations is used to explore theα-decay of superheavy nuclei.The known nuclei with Z=106−118 are chosen as examples for testing.The calculated half-lives ofα-decay agree with the experimental data better than those from the GLDM with the shell correction in the Weizsa¨cker-Skyrme model.Moreover,the influence of the decay energy Q_(α) onα-decay is investigated.It is determined that the Q_(α) values obtained from the WS4 model with radial basis function(RBF)correction match the experimental data optimally.Owing to these advantages,the GLDM with the RHF shell correction and WS4+RBF Q_(α) values is adopted to predict theα-decay lifetime for the unknown superheavy nuclei with Z=118−120.The trend of the availableα-decay half-lives according to the neutron number is similar to the trends of the values from the GLDM calculation without shell correction as well as the universal decay law(UDL)formula.Comparably,the RHF shell correction depresses(raises)theα-decay lifetime for most nuclei with N<186(N>186).In comparison with the half-lives of spontaneous fission,it can be concluded that theα-decay is dominant in the superheavy nuclei ^(281−304)118,^(284−306)119,and ^(287−308)120.These results are beneficial to the exploration of superheavy nuclei in experiments.

Improved macroscopic microscopic mass formula

A nuclear mass formula based on the macroscopic microscopic approach is proposed,in which the number of model parameters is reduced compared with other macroscopic microscopic models.The root mean square(RMS)deviation with respect to 2314 training sets(measured nuclear masses)is reduced to 0.447 MeV,and the calculated value of each nucleus is no more than 0.8%different from the experimental value.The single and two nucleon separation energies and the shell gaps are calculated to test the model.The shell corrections and double magic number of superheavy nuclei are also analyzed.

Systematic study of theαdecay preformation factors of the nuclei around the Z=82,N=126 shell closures within the generalized liquid drop model

In this study,we systematically investigate theαdecay preformation factors,Pα,and theαdecay half-lives of 152 nuclei around Z=82,N=126 closed shells based on the generalized liquid drop model(GLDM)with Pαbeing extracted from the ratio of the calculatedαdecay half-life to the experimental one.The results show that there is a remarkable linear relationship between Pαand the product of valance protons(holes)Np and valance neutrons(holes)Nn.At the same time,we extract theαdecay preformation factor values of the even–even nuclei around the Z=82,N=126 closed shells from the study of Sun et al.[J.Phys.G:Nucl.Part.Phys.,45:075106(2018)],in which theαdecay was calculated by two different microscopic formulas.We find that theαdecay preformation factors are also related to NpNn.Combining with our previous studies[Sun et al.,Phys.Rev.C,94:024338(2016);Deng et al.,ibid.96:024318(2017);Deng et al.,ibid.97:044322(2018)]and that of Seif et al.,[Phys.Rev.C,84:064608(2011)],we suspect that this phenomenon of linear relationship for the nuclei around the above closed shells is model-independent.This may be caused by the effect of the valence protons(holes)and valence neutrons(holes)around the shell closures.Finally,using the formula obtained by fitting theαdecay preformation factor data calculated by the GLDM,we calculate theαdecay half-lives of these nuclei.The calculated results agree with the experimental data well.

Spontaneous Fission Barriers Based on a Generalized Liquid Drop Model

The barrier against the spontaneous fission has been determined within the Generalized Liquid Drop Model （GLDM） including the mass and charge asymmetry, and the proximity energy. The shell correction of the spherical parent nucleus is calculated by using the Strutinsky method, and the empirical shape-dependent shell correction is 6mp10yed during the deformation process. A quasi-molecular shape sequence has been defined to describe the whole process from one-body shape to two-body shape system, and a two-touching-ellipsoid is adopted when the superdeformed one-body system reaches the rupture point. On these bases the spontaneous fission barriers are systematically studied for nuclei from 2a^Th to 249 Cm for different possible exiting channels with the different mass and charge asymmetries. The double, and triple bumps are found in the fission potential energy in this region, which roughly agree with the experimental results. It is found that at around Sn-like fragment the outer fission barriers are lower, while the partner of the Sn-like fragment is in the range near l^SRu where the ground-state mass is lowered by allowing axially symmetric shapes. The preferable fission channels are distinctly pronounced, which should be corresponding to the fragment mass distributions.

Bayesian evaluation of energy dependent neutron induced fission yields

From both the fundamental and applied perspectives, fragment mass distributions are important observablesof fission. We apply the Bayesian neural network (BNN) approach to learn the existing neutron induced fissionyields and predict unknowns with uncertainty quantification. Comparing the predicted results with experimentaldata, the BNN evaluation results are found to be satisfactory for the distribution positions and energy dependenciesof fission yields. Predictions are made for the fragment mass distributions of several actinides, which may beuseful for future experiments.