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1.
This paper introduces an approach for providing the Spatial Location (SLO) information of the Session Initiation Protocol (SIP) devices connected to wire and wireless IP networks. The aim of the paper is to set up the framework for providing emergency call services. This method uses SIP as transport and the SLO as data format inserted in the SIP payload. It analyses the relationship among the network elements involved in the architecture, and its functionality for providing emergency call services using SIP. In conclusion, this proposal track down an emergency call via SIP, and additionally enables SIP to support some other location-related services such as messaging, and location-based commerce.  相似文献   

2.
Detailed location information of mobile objects, for example that of a user with a mobile computer or phone, is an important input for many location-aware applications. However, constantly updating the location information for thousands of mobile objects is not feasible. Therefore, special update protocols for location information are required that transmit the information as efficiently as possible, that is requiring only few update messages, while still being effective in returning the location information with the desired accuracy. Different classes of such update protocols are described in this paper and a new combined protocol is proposed. To be able to compare their effectiveness and efficiency, we present an analysis for the minimum and average resulting accuracy of the location information in comparison with the number of messages transmitted. We also present the results of simulations that we have performed to back up our analysis.  相似文献   

3.
Although business firms have improved their environmental performance, a variety of forces are pushing businesses toward adopting environmental management throughout the entire life cycle of their products and processes. In this article we discuss the information systems elements of an environmental management approach we call "life-cycle-oriented environmental management" (LCOEM).This approach requires the firm to manage the effects of its processes from the creation of inputs to the final disposal of outputs, that is, from cradle to grave. We present a framework of the classes of information systems needed, describe their use in an LCOEM setting and define their inter relationships. We conclude with a discussion of the implications of LCOEM information systems.  相似文献   

4.
The validity of material flow analyses (MFAs) depends on the available information base, that is, the quality and quantity of available data. MFA data are cross‐disciplinary, can have varying formats and qualities, and originate from heterogeneous sources, such as official statistics, scientific models, or expert estimations. Statistical methods for data evaluation are most often inadequate, because MFA data are typically isolated values rather than extensive data sets. In consideration of the properties of MFA data, a data characterization framework for MFA is presented. It consists of an MFA data terminology, a data characterization matrix, and a procedure for database analysis. The framework facilitates systematic data characterization by cell‐level tagging of data with data attributes. Data attributes represent data characteristics and metainformation regarding statistical properties, meaning, origination, and application of the data. The data characterization framework is illustrated in a case study of a national phosphorus budget. This work furthers understanding of the information basis of material flow systems, promotes the transparent documentation and precise communication of MFA input data, and can be the foundation for better data interpretation and comprehensive data quality evaluation.  相似文献   

5.
周馥  邢树平 《植物学通报》2000,17(3):274-275
介绍了一种半薄切片定位样品的方法。此法与前人的方法不同之处在于位于载玻片之上被重新包埋于塑料环内的切片与载玻片的分离真人处步骤是“切片被包埋聚合好后,立即从60 ̄65℃温箱内被转入冰箱冷冻室中(-18℃)放置5 ̄10分钟。然后,将载玻征从冷冻室中取出,轻推塑料环,即可使包埋在塑料环内的切片与载玻片分离。这一方法成功地解决了样品中靶细胞的发育时期确定和样品丢失问题。而且还有简单、易操作和成功率高等优  相似文献   

6.
以湘桂黔侗族聚居区统计数据、田野调查资料和矢量地图为数据源,运用ArcGIS空间分析工具分析侗族村寨的选址布局特征以及其中蕴含的生态智慧内容。结果表明:1)传统侗族村寨主要在海拔500~900m,坡度7°~15°,坡向为北或西北方,与水源距离小于100m的区域选址建寨;2)侗族村寨整体上在高程、坡度、坡向和与水系距离上属于高值分布,侗族村寨选址布局的空间特征与地理环境因素密切相关;3)传统侗寨的选址布局具有地势中等、坡度适宜、背风向阳、易取水的特点,蕴含着主动适应环境的生态智慧,体现了“因地制宜、与自然共生”的生态思想,对于维持人地和谐具有积极意义。  相似文献   

7.
Understanding the root molecular and genetic causes driving complex traits is a fundamental challenge in genomics and genetics. Numerous studies have used variation in gene expression to understand complex traits, but the underlying genomic variation that contributes to these expression changes is not well understood. In this study, we developed a framework to integrate gene expression and genotype data to identify biological differences between samples from opposing complex trait classes that are driven by expression changes and genotypic variation. This framework utilizes pathway analysis and multi-task learning to build a predictive model and discover pathways relevant to the complex trait of interest. We simulated expression and genotype data to test the predictive ability of our framework and to measure how well it uncovered pathways with genes both differentially expressed and genetically associated with a complex trait. We found that the predictive performance of the multi-task model was comparable to other similar methods. Also, methods like multi-task learning that considered enrichment analysis scores from both data sets found pathways with both genetic and expression differences related to the phenotype. We used our framework to analyze differences between estrogen receptor (ER) positive and negative breast cancer samples. An analysis of the top 15 gene sets from the multi-task model showed they were all related to estrogen, steroids, cell signaling, or the cell cycle. Although our study suggests that multi-task learning does not enhance predictive accuracy, the models generated by our framework do provide valuable biological pathway knowledge for complex traits.  相似文献   

8.
Information Quality (IQ) is a critical factor for the success of many activities in the information age, including the development of data warehouses and implementation of data mining. The issue of IQ risk is recognized during the process of data mining; however, there is no formal methodological approach to dealing with such issues.

Consequently, it is essential to measure the risk of IQ in a data warehouse to ensure success in implementing data mining. This article presents a methodology to determine three IQ risk characteristics: accuracy, comprehensiveness, and non-membership. The methodology provides a set of quantitative models to examine how the quality risks of source information affect the quality for information outputs produced using the relational algebra operations: Restriction, Projection, and Cubic product. It can be used to determine how quality risks associated with diverse data sources affect the derived data. The study also develops a data cube model and associated algebra to support IQ risk operations.  相似文献   


9.
The concept of positional information is central to our understanding of how cells determine their location in a multicellular structure and thereby their developmental fates. Nevertheless, positional information has neither been defined mathematically nor quantified in a principled way. Here we provide an information-theoretic definition in the context of developmental gene expression patterns and examine the features of expression patterns that affect positional information quantitatively. We connect positional information with the concept of positional error and develop tools to directly measure information and error from experimental data. We illustrate our framework for the case of gap gene expression patterns in the early Drosophila embryo and show how information that is distributed among only four genes is sufficient to determine developmental fates with nearly single-cell resolution. Our approach can be generalized to a variety of different model systems; procedures and examples are discussed in detail.  相似文献   

10.
张振慧  王勇献  王正华 《激光生物学报》2007,16(2):249-252,F0003
细胞凋亡蛋白对生物体的发育、维持内环境稳定及人们理解细胞凋亡机制非常重要。文中提出了一种新的蛋白质序列特征提取方法—三肽离散源方法。计算了蛋白质序列中紧邻三联体的出现个数,利用离散增量极小化对凋亡蛋白进行定位预测;同时推广了张春霆等提出的内容平衡精度指数,使其能评估任意类的分类问题。实验结果表明:在凋亡蛋白定位预测研究中,三肽离散源方法在提高总体预测精度的同时,能够较好的解决样本不均衡问题;而内容平衡精度指数能比传统的总体预测精度更准确的评估预测算法的预测能力,有效的反映预测算法对样本不均衡问题的相容能力。  相似文献   

11.
The ability to evaluate the validity of data is essential to any investigation, and manual “eyes on” assessments of data quality have dominated in the past. Yet, as the size of collected data continues to increase, so does the effort required to assess their quality. This challenge is of particular concern for networks that automate their data collection, and has resulted in the automation of many quality assurance and quality control analyses. Unfortunately, the interpretation of the resulting data quality flags can become quite challenging with large data sets. We have developed a framework to summarize data quality information and facilitate interpretation by the user. Our framework consists of first compiling data quality information and then presenting it through 2 separate mechanisms; a quality report and a quality summary. The quality report presents the results of specific quality analyses as they relate to individual observations, while the quality summary takes a spatial or temporal aggregate of each quality analysis and provides a summary of the results. Included in the quality summary is a final quality flag, which further condenses data quality information to assess whether a data product is valid or not. This framework has the added flexibility to allow “eyes on” information on data quality to be incorporated for many data types. Furthermore, this framework can aid problem tracking and resolution, should sensor or system malfunctions arise.  相似文献   

12.
A distinction between different notions of “structure” and “function” is suggested for interpreting the overwhelming amount of data on microbiome structure and function. Sequence data, biochemical agents, interaction networks, taxonomic communities, and their dynamics can be linked to potential or actual biochemical activities, causal roles, and selected effects, respectively. This conceptual clarification has important methodological consequences for how to interpret existing data and approach open questions in contemporary microbiome research practice. In particular, the field will have to start thinking about notions of function more directly. Also see the video abstract here https://youtu.be/j5pq5uGld1k .  相似文献   

13.
地理信息系统及其在动物空间行为研究中的应用   总被引:1,自引:0,他引:1  
空间属性是动物行为的重要特征,也是行为生态学研究中必须要面对的难题之一。地理信息系统(Geographic Information System,GIS)具有强大的空间分析功能,它在动物行为生态学研究中得到了越来越广泛的应用,如生境选择、领域分析、迁徙路线、活动节律等。本文较系统地阐述了GIS的原理以及在行为生态学研究中所涉及的基本概念和原理,对近年来利用GIS进行的行为生态学研究做了回顾和总结,并对其未来的发展进行了展望。  相似文献   

14.
Urban mining offers an efficient supply of resources because of rich mines and low environmental impacts. Location selection and optimization for urban mining facilities is more complicated than for natural mines, given that it may vary according to the urban population, consumption habits, and economic development. China initiated the National Urban Mining Pilot Bases program in 2010 that targeted 50 national urban mining pilot bases, but unfortunately neglected the location planning issue. Twenty‐eight bases have already been selected, which are concentrated in the central and eastern areas of China. This article combines the use of analytic hierarchy process, maximal covering location model, and geographical information systems (GIS) software to optimize locations for China's urban mining pilot bases. Primary findings show that, theoretically, 40 urban mining pilot bases can sufficiently provide maximum gross domestic product (GDP) and population coverage service for China. Taking the current 28 bases as a precondition and 50 bases as the remaining policy target, our second optimization results in a list of 22 cities for the location selection of future urban mining pilot bases. In total, the optimized 22 cities, together with the selected 28 bases, can provide a maximum 97.5% of GDP and 95.1% of population coverage in China. This study illustrates the optimization process for urban mining recycling facilities in general and provides policy advice for China in a specific case.  相似文献   

15.
Ursolic acid (URS), an ursane-representative bioactive pentacyclic triterpene, is a plant secondary metabolite presenting a great number of pharmacological beneficial properties. Due to the prominent hydrophobic character of URS and its high phospholipid/water partition coefficient, some of its possible effects on biological systems might be related to its capacity to interact with and locate into the membrane as well as interact specifically with its components. In this work, we have studied the location and orientation of URS in the membrane by molecular dynamics simulations. At the end of the simulation, URS locates near the surface in vicinity to the phospholipid headgroups but its orientation depends on lipid composition, its final average orientation being a nearly parallel one in POPC but a nearly perpendicular one in POPC/POPE/POPG/PSM/Chol. Furthermore, in the complex lipid system URS seems to interact specifically with POPE, PSM, and Chol excluding POPG from its surroundings, which could lead to phase separation and domain formation. The different disposition of URS in the membrane and its specific interaction with certain lipid types could lead to a significant perturbation of the membrane structure. The important pharmacological activities of URS would rely on the effects it exerts on the membrane structure in general and the existence of specific interactions with specific lipids in particular.  相似文献   

16.
谷子雄性不育系1066A不育基因和黄苗基因的染色体定位   总被引:7,自引:0,他引:7  
以谷子(Setaria italica(L).Beauv.)雄性不育系1066A为母本,豫谷1号三体(1-7)及四体8和四体9作父本进行杂交,应用初极三体分析法,进行了谷子雄性不育基因和黄苗基因的染色体定位研究。通过配置大时杂交组合和反复授粉,利用豫谷1号三体的极少量花粉,获得了三体2-9的F1代杂种,各杂种三体的形态与豫谷1号三体基本个似,略有差异,苗色呈绿色且可育。杂种F2植株的育性都产生分离。结果是三体3、5、7、8、9的F2代分离出的可育株与不育标之比为3:1,三体6的可育株与不育株之比为14:1(x^2=0.012,p=0.01)。杂种F2分离出的绿苗与黄苗之比只有三体7为12:1(X^2=0.36,P=0.01),其他均为3:1。因此,可以确定1066A的不育基因为隐性单基因,位于第6号染色体上,该品系的黄苗基因也是隐性单基因,位于第7号染色体上。  相似文献   

17.
以谷子(Setaria italica (L.) Beauv.)雄性不育系1066A为母本,豫谷1号三体(1~7)及四体8和四体9作父本进行杂交,应用初级三体分析法,进行了谷子雄性不育基因和黄苗基因的染色体定位研究.通过配置大量杂交组合和反复授粉,利用豫谷1号三体的极少量花粉,获得了三体2~9的F1代杂种,各杂种三体的形态与豫谷1号三体基本相似,略有差异,苗色呈绿色且可育.杂种F2植株的苗色和育性都产生分离.结果是三体3、5、7、8、9的F2代分离出的可育株与不育株之比为3∶1,三体6的可育株与不育株之比为14∶1 (χ2=0.012,P=0.01).杂种F2分离出的绿苗与黄苗之比只有三体7为12∶1 (χ2=0.36, P=0.01),其他均为3∶1.因此,可以确定1066A的不育基因为隐性单基因,位于第6号染色体上,该品系的黄苗基因也是隐性单基因,位于第7号染色体上.  相似文献   

18.
Understanding of tibiofemoral joint mechanics at multiple spatial scales is essential for developing effective preventive measures and treatments for both pathology and injury management. Currently, there is a distinct lack of specimen-specific biomechanical data at multiple spatial scales, e.g., joint, tissue, and cell scales. Comprehensive multiscale data may improve the understanding of the relationship between biomechanical and anatomical markers across various scales. Furthermore, specimen-specific multiscale data for the tibiofemoral joint may assist development and validation of specimen-specific computational models that may be useful for more thorough analyses of the biomechanical behavior of the joint. This study describes an aggregation of procedures for acquisition of multiscale anatomical and biomechanical data for the tibiofemoral joint. Magnetic resonance imaging was used to acquire anatomical morphology at the joint scale. A robotic testing system was used to quantify joint level biomechanical response under various loading scenarios. Tissue level material properties were obtained from the same specimen for the femoral and tibial articular cartilage, medial and lateral menisci, anterior and posterior cruciate ligaments, and medial and lateral collateral ligaments. Histology data were also obtained for all tissue types to measure specimen-specific cell scale information, e.g., cellular distribution. This study is the first of its kind to establish a comprehensive multiscale data set for a musculoskeletal joint and the presented data collection approach can be used as a general template to guide acquisition of specimen-specific comprehensive multiscale data for musculoskeletal joints.  相似文献   

19.
Sixty lactating Holstein cows were treated, in 3 groups, with Folltropin and Estrumate to induce superovulation and then bred by artificial insemination (AI). Embryos were collected at slaughter on D 4, 5 or 6 after insemination by flushing separately the oviducts, uterine tip and the remainder of the uterine horn. The embryos and ova recovered accounted for 64.6 ± 4.3% of the ovulations, and there were no differences due to day, side or group. On D 4, 60% of the embryos were found in the oviducts; on Days 5 and 6, 80 and 91%, respectively, were found in the tip of the uterine horn. Viability was independent of the site of recovery; over 91% of the embryos grew and developed in culture for at least 3 d.  相似文献   

20.
由于重庆地区的医疗水平参差不齐,所以建设重庆地区区域医疗影像信息化系统,实现各类影像信息共享,对提供高效的医疗卫生服务具有非常重要的意义。目前,建设重庆地区区域医疗影像交互平台面临着整体设计集成程度和扩展性不高、医学影像标准不统一、数据安全与质量标准不完整、平台没有整合大数据分析挖掘方法等问题。为此,首先对重庆地区区域影像平台的整体结构进行了设计,提出了区域影像交互平台的五层体系结构;其次在五层体系结构基础上制定和加强了影像数据标准和信息安全体系;并且在区域影像中心的基础上,嵌入了医学影像大数据分析工具。应用结果证明,交互平台具有较高的集成程度和扩展性,平台标准的制定和加强能有效的提高交互效率,加强数据安全和质量管理,并且平台可对海量数据进行有效的分析。  相似文献   

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