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1.
This paper focuses on the role of punishment as a critical social mechanism for cheating prevention in MMORPGs. The role of punishment is empirically investigated in a case study of the MMORPG Tibia (Cipsoft 1997–2011) () and by focusing on the use of bots to cheat. We describe the failure of punishment in Tibia, which is perceived by players as one of the elements facilitating the proliferation of bots. In this process some players act as a moral enterprising group contributing to the reform of the game rules and in particular to the reform of the Tibia punishment system by the game company. In the conclusion we consider the ethical issues raised by our findings and we propose some general reflections on the role of punishment and social mechanisms for the governance of online worlds more generally.  相似文献   

2.
内孤立波是陆架陆坡区一种常见的现象。本文借助于一个两层非静力近似模式(Gerkema,1996)模拟分析了内孤立波在陆架生成及传播特性,并与已有的观测资料进行了比较分析。结果表明,正压潮与地形相互作用激发生成内潮,内潮在向岸传播过程中,由于正压潮流及自身的非线性作用而发生分裂,受频散作用的影响进一步演化成内孤立子波列。而对于离岸传播的内潮,由于较强的频散效应,非线性与频散在较大尺度上达到平衡,从而使得波形呈现椭圆余旋波的特征。  相似文献   

3.
对家兔骨折进行治愈对比,测量并发症死亡和骨痂生长,结果:三元能量治疗组死亡率低、骨痂生长良好,证明三元能量有镇痛、提高机体免疫和加速动物骨折后愈合等效用。  相似文献   

4.
Wound healing is an essential physiological process for tissue homeostasis, involving multiple types of cells, extracellular matrices, and growth factor/chemokine interactions. Many in vitro studies have investigated the interactions between cues mentioned above; however, most of them only focused on a single factor. In the present study, we design a wound healing device to recapitulate in vivo complex microenvironments and heterogeneous cell situations to investigate how three types of physiologically related cells interact with their microenvironments around and with each other during a wound healing process. Briefly, a microfluidic device with a micropillar substrate, where diameter and interspacing can be tuned to mimic the topographical features of the 3D extracellular matrix, was designed to perform positional cell loading on the micropillar substrate, co-culture of three types of physiologically related cells, keratinocytes, dermal fibroblasts, and human umbilical vein endothelial cells, as well as an investigation of their interactions during wound healing. The result showed that cell attachment, morphology, cytoskeleton distribution, and nucleus shape were strongly affected by the micropillars, and these cells showed collaborative response to heal the wound. Taken together, these findings highlight the dynamic relationship between cells and their microenvironments. Also, this reproducible device may facilitate the in vitro investigation of numerous physiological and pathological processes such as cancer metastasis, angiogenesis, and tissue engineering.  相似文献   

5.
In certain arteries the flow rate of blood can now be quantified by a non-invasive technique based on a newly developed ultrasound velocity profile meter. Clinical applications of this technique indicate that a reliable mathematical model of the circulatory system would facilitate the identification of pathologic patterns of flow rate and the corresponding possible causes. A relatively simple law for the viscoelastic behavior of arterial conduits is hypothesized and its influence on the phasis variations of pressure and flow examined with the aid of the method of characteristics. To test the feasibility of this model, its predictions of the attenuation and dispersion of small sinusoidal pressure waves are compared with data obtained in animal experiments. The results show good agreement and verify the significance of taper in reducing the attenuation of waves propagating towards the periphery and conversely increasing the damping of waves moving towards the heart. Beside this the natural pressure and flow pulses generated by the heart appear to be attenuated in a realistic manner: they no longer exhibit the somewhat exaggerated peaking predicted by the theoretical model when the viscoelasticity of the vessel wall is neglected.  相似文献   

6.
张瑞  周万坤  陈倩竹 《科研管理》2020,41(10):210-217
知识是企业最为重要的战略性资源,为了提高知识的价值,企业需要促进员工间知识共享行为以增加其竞争优势。在有限理性的基础上,构建知识共享行为的演化博弈模型,依此分析影响员工间知识共享行为的因素,探究组织信任对知识共享行为的影响。结果表明,知识数量、知识贡献系数、共享奖励系数和共享惩罚系数与知识共享行为正相关而共享风险系数和成本系数与知识共享行为反相关,情感信任促进知识获取而认知信任促进知识贡献。  相似文献   

7.
应急地震学的研究进展   总被引:6,自引:0,他引:6       下载免费PDF全文
因孕震过程很难进行直接观测,人类对孕震过程及地震破裂起始过程了解尚少,地震的短临预报在短期难以取得突破。目前美、日等发达国家及地区采取的对策是,强化建筑物抗震设防、深化地震快速应急研究。应急地震学是指在地震发生后以最短的时间确定地震的位置及强度,利用现代通信的快速性,在破坏性地震波(主要是地震面波)达到之前几到几十秒的时间内采取适当的措施,避免一些人员财产损失,形成地震预警系统。应急地震学另一个重要内容则是地震灾害的快速估计,即利用国家及全球的地震波形信息,结合地震灾区的强地面震动记录,快速确定地震的起始、终止时间、地点及能量释放的具体过程,结合当地地质结构信息,从而估计各地区可能的受灾程度,为合理分配救灾资源提供第一手资料。在进一步加密我国地震台网的基础上,在东部平原大都市地区我国应可实现强震(6.5级以上)发生后20秒内快速确定震中及震级,实现地震极早期预警。同时可在几小时内确定地震能量释放过程,形成地面震动理论评估图(shakemap),按照灾情程度合理分配救灾资源,提高救灾效率。  相似文献   

8.
The progress of fracture union requires close monitoring. Whereas, clinical examination and radiographic studies assess the outcome, biochemical markers like serum alkaline phosphatase and urinary hydroxyproline reflect the actual status of bone resorption and bone formation over a short time frame. 36 patients of long bone fracture were randomly allocated for the study. When the patient reported to the Department of Orthopedics after fracture, serum and urinary samples were collected and X-ray of the affected part were taken. Subsequent samples were collected and X-ray taken just after management (either operative or conservative), after 3rd, 5th, 8th and 12th week, respectively after onset of fracture. According to the course of callus formation the patients were divided into two groups that progressed to proper union or malunion. The levels of serum alkaline phosphatase, urinary total and free hydroxyproline levels were measured and statistically analysed and compared. A statistically significant positive correlation between total urinary hydroxyproline excretion and serum alkaline phosphatase indicate progress towards satisfactory union. Thus, serial monitoring of biochemical markers of bone turnover can be used as an adjunct to clinical and radiological evidence of fracture healing.  相似文献   

9.
固体中冲击波及其一维一阶非线性演化方程数值模拟   总被引:1,自引:0,他引:1  
定义固体中的冲击波为冲击波阵面及其后状态物理量发生急剧变化的狭窄区域。利用前人讨论结果进一步探讨了 4种边界输入形式下的冲击波形成距离计算式。分别采用具有二阶精度的显式MacCormack差分格式和MacCormackTVD格式对黏弹性、热弹性以及非均匀性非线性固体介质中一维一阶非线性演化方程进行数值模拟研究,探讨了这些复杂介质中冲击波的形成及演化的基本性质,并较成功地避免了非物理解的产生  相似文献   

10.
目的探讨记忆合金环抱器治疗四肢骨干骨折的临床价值。方法自2003年2月-2005年2月,采用记忆合金治疗四肢骨干骨折38例,并全部随访。结果参照庄起昌制订的标准,优20例,良15例,可2例,差1例。结论记忆合金对骨质及血运损伤小,固定牢固,有利于骨折的愈合和肢体功能恢复,值得临床推广应用。  相似文献   

11.
自愈环是SDH组网最常用的结构方案,本论文探讨了几种自愈环的原理,分析其各自的特点及应用场合,着重研究了各种自愈环的容量,得出了复用段保护环信道利用率要大大高于通道保护倒换环的结论,并且论述了如何根据网络所处层次、业务分布等原因灵活使用各种自愈环。  相似文献   

12.
针对民营孵化器以盈利为核心目标,增加盈利绩效和服务能力反映民营孵化器当前和未来盈利能力,构建了多层次民营孵化器绩效评价指标体系。借鉴CRITIC法赋权思路,提出基于改进CRITIC的组合评价方法:先分别运用层次分析法、熵理想点法和标准离差法评价;以标准差法衡量三种评价值纵向差异度,改CRITIC法中线性相关系数为灰关联度来反映横向相似性,最后综合横向相似度和纵向差异度获得评价方法组合权重。实例应用表明该组合评价方法可行和有效。  相似文献   

13.
车辆对不平整路面的随机动压力分析   总被引:1,自引:0,他引:1  
采用双自由度四分之一车辆模型,以路面不平整和车辆发动机振动为激励,运用随机过程理论分析了车辆对不平整路面的随机动压力,得到了车辆动压系数的概率分布以及最大动压系数与路面不平整度、车速、悬挂质量以及悬挂系统与非悬挂系统特性之间的关系。算例分析表明,引起车辆振动的路面不平整波形的频率范围主要集中在0.04~2.0之间,最大动压系数随路面不平整度、车速、悬挂与非悬挂系统刚度的增大而增大,随着悬挂质量以及悬挂系统阻尼的增大而减少,而轮胎阻尼对车辆动荷载的影响并不显著。  相似文献   

14.
Dictionary-based query translation for cross-language information retrieval often yields various translation candidates having different meanings for a source term in the query. This paper examines methods for solving the ambiguity of translations based on only the target document collections. First, we discuss two kinds of disambiguation technique: (1) one is a method using term co-occurrence statistics in the collection, and (2) a technique based on pseudo-relevance feedback. Next, these techniques are empirically compared using the CLEF 2003 test collection for German to Italian bilingual searches, which are executed by using English language as a pivot. The experiments showed that a variation of term co-occurrence based techniques, in which the best sequence algorithm for selecting translations is used with the Cosine coefficient, is dominant, and that the PRF method shows comparable high search performance, although statistical tests did not sufficiently support these conclusions. Furthermore, we repeat the same experiments for the case of French to Italian (pivot) and English to Italian (non-pivot) searches on the same CLEF 2003 test collection in order to verity our findings. Again, similar results were observed except that the Dice coefficient outperforms slightly the Cosine coefficient in the case of disambiguation based on term co-occurrence for English to Italian searches.  相似文献   

15.
高新技术企业中知识分享微观机制研究   总被引:1,自引:0,他引:1       下载免费PDF全文
吴丙山  赵骅  罗军 《科研管理》2012,33(3):65-71
论文从主从博弈的视角,将高新技术企业运营的基础单位知识团队作为研究对象,运用博弈中的主方和从方来刻画知识团队中成员间知识水平的差异,通过分析各方投入、绩效分配、安全系数等对知识分享的影响,建立起高新技术企业知识团队中知识分享决策的主从博弈微观模型,并进行仿真分析,探索高新技术企业知识分享过程中的内在微观机理及其影响机制。论文研究发现成员的知识分享绩效分配系数与知识分享投入正相关,知识分享安全指数对知识分享投入与知识分享收益均有积极的影响;知识团队中知识分享前提条件是知识优势方的绩效分配系数应足够大,且该绩效分配系数与所有跟随者的绩效分配系数之和的比值应大于知识转化系数;研究结论为高新技术企业的知识分享策略制定提供决策参考。  相似文献   

16.
构建的指标体系是否具有合理性直接影响着后续评价结果的准确性。立足于高校科技创新过程与区域创新系统分析角度,通过指标定性与定量筛选方法相结合,构建高校科技创新能力评指标体系。运用复相关系数分析剔除易被其他指标替代的指标,避免指标间信息重叠;通过灰色关联分析剔除对评价目标不重要的指标,保留对评价结果影响显著的指标。计算灰色关联分析中的分辨系数值,提高灰色关联度的准确度。以我国31个省级行政区为样本,最终构建包含27个指标的基于区域视角的高校科技创新能力评价指标体系。最终筛选出的指标集保留了90.7%的原始指标集信息。  相似文献   

17.
This paper deals with the problem of model reference control for linear parameter varying (LPV) systems. The LPV systems under consideration depend on a set of parameters that are bounded and available online. The main contribution of this paper is to design an LPV model reference control scheme for LPV systems whose state-space matrices depend affinely on a set of time-varying parameters that are bounded and available online. The design problem is divided into two subproblems: the design of the coefficient matrices of the controller and the design of the gain of the state feedback controller for LPV systems. The singular value decomposition is used to obtain the coefficient matrices, while the linear matrix inequality methodology is used to obtain the parameter-dependent state feedback gain of the control scheme. A simple numerical example is used to illustrate the proposed design and a coupled-tank process example is used to demonstrate the usefulness and practicality of the proposed design. Simulation and experimental results indicate that the proposed scheme works well.  相似文献   

18.
Surface acoustic waves (SAWs) have been used as a rapid and efficient technique for driving microparticles into a three-dimensional scaffold matrix, raising the possibility that SAW may be effective in seeding live cells into scaffolds, that is, if the cells were able to survive the infusion process. Primary osteoblast-like cells were used to specifically address this issue: To investigate the effects of SAW on the cells’ viability, proliferation, and differentiation. Fluorescence-labeled osteoblast-like cells were seeded into polycaprolactone scaffolds using the SAW method with a static method as a control. The cell distribution in the scaffold was assessed through image analysis. The cells were far more uniformly driven into the scaffold with the SAW method compared to the control, and the seeding process with SAW was also significantly faster: Cells were delivered into the scaffold in seconds compared to the hour-long process of static seeding. Over 80% of the osteoblast-like cells were found to be viable after being treated with SAW at 20 MHz for 10–30 s with an applied power of 380 mW over a wide range of cell suspension volumes (10–100 μℓ) and cell densities (1000–8000 cells∕μℓ). After determining the optimal cell seeding parameters, we further found that the treated cells offered the same functionality as untreated cells. Taken together, these results show that the SAW method has significant potential as a practical scaffold cell seeding method for tissue and orthopedic engineering.  相似文献   

19.
本文将数据挖掘聚类分析技术融合到ETC运营管理过程中,分析了ETC交易数据三种关键的特征数据并构建了数据模型,采用轮廓系数对聚类结果进行科学评估。在聚类分析结果的基础上,对ETC用户进行二维分类,提出ETC的推广营销和ETC系统维护管理的方法和建议。  相似文献   

20.
To evaluate the magnitude of bone loss in postmenopausal women and to study the effect of a selective estrogen Receptor Modulator, raloxifene, on bone loss by quantitative ultrasound of calcaneus and serum bone specific alkaline phosphatase (BAP). Postmenopausal women with ostesopenia/osteoporosis were assigned randomly to receive placebo (n=30) or raloxifene (60mg/d, n=30) with calcium (500mg/day) and vitamin D (250 IU/day). The bone mineral density (BMD) and BAP levels were measured at the beginning of therapy and six months later. They were subjected to statistical analysis (t test, p value) using SPSS statistical package. 70% of postmenopausal women suffered from osteopenia/osteoporosis. After raloxifene therapy, there was improvement in the BMD but this was not statistically significant (p>0.05). There was a fall in the value of serum BAP by 26.6% (p<0.05). Raloxifene has a favourable effect on bone turnover as evident from changes in BMD and a significant fall in serum BAP.  相似文献   

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