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71.
Technological knowledge can be understood as a collective good when it is the outcome of the integration between internal to the firm investments in R&D and learning and the absorption of competencies and technologies provided by external organizations (such as, other firms, universities, R&D centers). Technological communication is a crucial strategy in such dynamic interaction between the firm and the system. Only under effective conditions of technological communication the private and social benefits derived from the exploitation of spillovers are higher than the private losses due to partial inappropriability. The article presents a simple microeconomic framework to understand knowledge production and distribution, integrating the effects and conditions of technological communication within a knowledge production function. The interaction between internal investments in R&D and learning, partial inappropriability, the conditions for the access to external knowledge and the exploitation of spillovers explains increasing returns in the production of knowledge.
Pier Paolo PatruccoEmail:
  相似文献   
72.
In many criminal and civil cases, some questioned documents are written with iron gall ink. Determining the date when an iron gall ink entry was written can be important to assess the authenticity of a document. A dissolution‐diffusion method was successfully employed to draw aging curves of iron gall ink entries stored in controlled conditions over 40 months. Calibration curves were created to indicate the relationship between the average dissolution‐diffusion rate of ink components and the age of ink entries stored under natural aging conditions. As preliminary findings of this study, the mixed solution of dimethyl formamide (DMF) and anhydrous ethanol was suitable to dissolve the dye of iron gall ink strokes made at different time. It was also determined that brands of iron gall inks, types of paper, and thickness of iron gall ink strokes had varying impacts on estimating the dates of iron gall ink strokes.  相似文献   
73.
The detection of latent traces is an important aspect of crime scene investigation. Blood stains on black backgrounds can be visualized using chemiluminescence, which is invasive and requires a darkened room, or near-infrared photography, for which investigators need to change filters manually to optimize contrast. We demonstrated the performance of visible reflectance hyperspectral imaging (400–720 nm) for this purpose. Several processing methods were evaluated: single wavelength bands, ratio images, principal component analysis (PCA), and “SIMPLe-to-use Interactive Self-modeling Mixture Analysis” (SIMPLISMA). Using these methods, we were able to enhance the contrast between blood stains and 12 different fabrics. On black cotton, blood dilutions were visible with a minimal concentration of 25% of whole blood. The hyperspectral camera system used in this study is portable and wireless, which makes it suitable for crime scene use. The described technique is noncontact and nondestructive, so all traces are preserved for further analysis.  相似文献   
74.
Blood spatter analysis is an important step for crime scene reconstruction. The presence of saliva in blood spatter could indicate expectorated blood which is difficult to distinguish from impact spatter. In this study, four saliva test methods (SALIgAE®, Phadebas® sheet, RSID-Saliva kit, and starch gel diffusion) were compared to identify the best method for detecting expectorated blood spatter. The RSID-Saliva kit showed the highest sensitivity even when saliva was mixed with blood, and was not inhibited by the presence of blood. The SALIgAE® test provided easy and rapid results, but the yellow color of a positive reaction was overwhelmed by the red color of the blood. The starch gel diffusion method and the Phadebas® sheet exhibited relatively low sensitivity and the assay took a long time. When using the RSID-Saliva kit for identifying saliva in blood, results should be read within 10 min.  相似文献   
75.
目的研究氯胺酮在大白兔体内死后弥散过程和再分布机制。方法 48只实验大白兔随机分为8组,采用缺氧处死后以150mg/kg氯胺酮灌胃,尸体仰卧位于室温下放置;在0~96h内分8个时间点各解剖1组,提取体液和脏器组织样品;采用GC/MS法定性结合GC-NPD法定量检测样品中氯胺酮含量,并计算心血/外周血中氯胺酮含量的比值。结果大白兔死后氯胺酮灌胃尸体放置96h内,脑、尿液、玻璃体液、左上/下肢肌肉样本中均未检测到氯胺酮,心血、外周血、心肌、脾、肾、肝、肺、胆汁中氯胺酮含量随死后时间呈动态升高的变化;其中距离胃较近的组织(如脾)较早检测到含量较高的氯胺酮,而距离较远的组织或体液中氯胺酮含量较低且较晚检测到;心血/外周血中氯胺酮含量比值为1.73。结论氯胺酮在家兔体内存在死后再分布,从胃到器官组织、心血顺浓度梯度弥散是主要机制。脑、玻璃体液、尿液、肢体肌肉不受死后弥散的影响,可作为生前服毒与死后染毒氯胺酮的鉴别依据。  相似文献   
76.
光谱成像在物证检验中的初步实验研究   总被引:13,自引:7,他引:6  
目的研究运用光谱成像技术进行物证形态检验的可能性和方法。方法比较相同条件下使用普通照相方法与光谱成像方法拍摄多种痕迹物证的效果。结果光谱成像检验的能力和效果都具有明显优势。结论光谱成像检验技术的出现使物证形态检验学的发展进入了一个崭新的阶段。  相似文献   
77.
What explains the variation in institutional adaptation of national parliaments to European integration? Whereas the existing literature has mainly focused on domestic conditions, this article explains institutional adaptation to integration by focusing on inter‐parliamentary diffusion. The argument draws on ‘learning’ mechanisms of diffusion on the demand side and on ‘emulation’ mechanisms on the supply side. Parliamentary demand for external inspiration is related to uncertainty about functional oversight institutions, and the selection of sources to perceptions of similarity and success. Demand arises in new European Union member parliaments and young democracies that then turn towards culturally alike countries and old democracies. Using spatial econometrics, support is demonstrated for the argument in the article while ruling out alternative diffusion mechanisms such as spatial proximity and learning from Scandinavian frontrunners once links along cultural similarity and democratic experience are controlled for. The results underline the limits of the ‘isolated polity’ approach in the comparative study of institutions in Europe's closely integrated political system, while also showing that, even in this favourable environment, diffusion pathways are contingent on the mechanisms generating demand among policy makers and shaping their selection of sources for external information.  相似文献   
78.
目的探讨CT和MRI检查方法在弥漫性轴索损伤(diffuse axonal injury,DAI)法医学鉴定中的应用价值。方法收集26例CT和MRI影像资料齐全的DAI鉴定资料进行回顾性分析,比较CT和MRI两种方法对DAI病灶检出率的差异,分析DAI病灶检出数量与法医学鉴定结果之间的关系。结果 26例经MRI检出DAI病灶787个,经CT检出DAI病灶32个,MRI对DAI病灶的敏感度显著高于CT(P0.01)具有统计学意义。26例DAI鉴定的伤残等级数值与影像学检查发现的病灶数量之间存在负相关(r=-0.908,P0.01)。结论 MRI检查对DAI病灶的检出率较CT检查具有明显优势,可为DAI诊断提供更为准确的依据,在法医临床学鉴定中具有重要的应用价值。  相似文献   
79.
These experiments were designed to determine whether skin debris (desquamated epithelial cells and apparent skin oils) affects gunshot residue (GSR) particle detection on the sticky tape lift samples prepared for scanning electron microscopy (SEM). A dabbing experiment showed that GSR particles accumulate not only on the adhesive surface of the sampler, but also on the epithelial cell surfaces. Samplers were loaded with target GSR followed by dabbing 30 times on the back of a hand. Backscatter electron images were taken at 20 kV and for some at 30 kV of the same areas. The samplers were then treated with a sodium/calcium hypochlorite solution (bleach) to remove skin debris and again imaged in the SEM. Comparison of these images shows more GSR particles will likely be revealed at 30 kV than 20 kV and more particles revealed by the bleach treatment in an automated SEM system.  相似文献   
80.
The resilience of autocratic regimes in various world regions and the emerging model of illiberal capitalist autocracies (China, Russia) have led scholars to shift their attention to the durability of such regimes. Autocracies not only resist the global spread of democracy, but are developing their own domestic efforts in the promotion of autocracy. This study argues that processes at the regional level aim at the dissemination and diffusion of autocratic norms, structures, processes, policy approaches or practices. Likewise, we propose that authoritarian gravity centres can be attributed with both the active promotion of autocracy as well as the inducement of diffusion effects. Our research tries to shed some light on their strategies and modes of influence on countries in their geopolitical proximity (target states).  相似文献   
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