At present,although knowledge graphs have been widely used in various fields such as recommendation systems,question and answer systems,and intelligent search,there are always quality problems such as knowledge omissi...At present,although knowledge graphs have been widely used in various fields such as recommendation systems,question and answer systems,and intelligent search,there are always quality problems such as knowledge omissions and errors.Quality assessment and control,as an important means to ensure the quality of knowledge,can make the applications based on knowledge graphs more complete and more accurate by reasonably assessing the knowledge graphs and fixing and improving the quality problems at the same time.Therefore,as an indispensable part of the knowledge graph construction process,the results of quality assessment and control determine the usefulness of the knowledge graph.Among them,the assessment and enhancement of completeness,as an important part of the assessment and control phase,determine whether the knowledge graph can fully reflect objective phenomena and reveal potential connections among entities.In this paper,we review specific techniques of completeness assessment and classify completeness assessment techniques in terms of closed world assumptions,open world assumptions,and partial completeness assumptions.The purpose of this paper is to further promote the development of knowledge graph quality control and to lay the foundation for subsequent research on the completeness assessment of knowledge graphs by reviewing and classifying completeness assessment techniques.展开更多
In the context of big data, many large-scale knowledge graphs have emerged to effectively organize the explosive growth of web data on the Internet. To select suitable knowledge graphs for use from many knowledge grap...In the context of big data, many large-scale knowledge graphs have emerged to effectively organize the explosive growth of web data on the Internet. To select suitable knowledge graphs for use from many knowledge graphs, quality assessment is particularly important. As an important thing of quality assessment, completeness assessment generally refers to the ratio of the current data volume to the total data volume.When evaluating the completeness of a knowledge graph, it is often necessary to refine the completeness dimension by setting different completeness metrics to produce more complete and understandable evaluation results for the knowledge graph.However, lack of awareness of requirements is the most problematic quality issue. In the actual evaluation process, the existing completeness metrics need to consider the actual application. Therefore, to accurately recommend suitable knowledge graphs to many users, it is particularly important to develop relevant measurement metrics and formulate measurement schemes for completeness. In this paper, we will first clarify the concept of completeness, establish each metric of completeness, and finally design a measurement proposal for the completeness of knowledge graphs.展开更多
目的研究蹲厕行为对胶囊内镜检查胃转运时间(gastric transit time,GTT)和全小肠检查率(complete examination rate of small bowel,CER)的影响。方法随机纳入2019年1-12月于重庆医科大学附属第二医院行胶囊内镜检查的患者122例,采用随...目的研究蹲厕行为对胶囊内镜检查胃转运时间(gastric transit time,GTT)和全小肠检查率(complete examination rate of small bowel,CER)的影响。方法随机纳入2019年1-12月于重庆医科大学附属第二医院行胶囊内镜检查的患者122例,采用随机数字表法将其分为试验组63例和对照组59例,试验组即吞服胶囊后随时可以蹲厕,对照组如需如厕采取坐便。比较2组患者GTT、小肠转运时间、CER和诊断率的区别。结果试验组和对照组患者在性别、年龄、住院情况等方面差异无统计学意义。试验组患者CER显著高于对照组(92.06%vs 79.66%),差异有统计学意义(P=0.048)。试验组患者中位GTT显著少于对照组(26.7 vs 45.6 min),差异有统计学意义(P=0.027)。两组患者在小肠转运时间和诊断率上差异无统计学意义。结论行胶囊内镜检查患者采用蹲厕行为能减少胶囊在胃内转运时间,增加全小肠检查率。展开更多
基金supported by the National Key Laboratory for Complex Systems Simulation Foundation(6142006190301)。
文摘At present,although knowledge graphs have been widely used in various fields such as recommendation systems,question and answer systems,and intelligent search,there are always quality problems such as knowledge omissions and errors.Quality assessment and control,as an important means to ensure the quality of knowledge,can make the applications based on knowledge graphs more complete and more accurate by reasonably assessing the knowledge graphs and fixing and improving the quality problems at the same time.Therefore,as an indispensable part of the knowledge graph construction process,the results of quality assessment and control determine the usefulness of the knowledge graph.Among them,the assessment and enhancement of completeness,as an important part of the assessment and control phase,determine whether the knowledge graph can fully reflect objective phenomena and reveal potential connections among entities.In this paper,we review specific techniques of completeness assessment and classify completeness assessment techniques in terms of closed world assumptions,open world assumptions,and partial completeness assumptions.The purpose of this paper is to further promote the development of knowledge graph quality control and to lay the foundation for subsequent research on the completeness assessment of knowledge graphs by reviewing and classifying completeness assessment techniques.
基金supported by the National Key Laboratory for Comp lex Systems Simulation Foundation (6142006190301)。
文摘In the context of big data, many large-scale knowledge graphs have emerged to effectively organize the explosive growth of web data on the Internet. To select suitable knowledge graphs for use from many knowledge graphs, quality assessment is particularly important. As an important thing of quality assessment, completeness assessment generally refers to the ratio of the current data volume to the total data volume.When evaluating the completeness of a knowledge graph, it is often necessary to refine the completeness dimension by setting different completeness metrics to produce more complete and understandable evaluation results for the knowledge graph.However, lack of awareness of requirements is the most problematic quality issue. In the actual evaluation process, the existing completeness metrics need to consider the actual application. Therefore, to accurately recommend suitable knowledge graphs to many users, it is particularly important to develop relevant measurement metrics and formulate measurement schemes for completeness. In this paper, we will first clarify the concept of completeness, establish each metric of completeness, and finally design a measurement proposal for the completeness of knowledge graphs.
文摘目的研究蹲厕行为对胶囊内镜检查胃转运时间(gastric transit time,GTT)和全小肠检查率(complete examination rate of small bowel,CER)的影响。方法随机纳入2019年1-12月于重庆医科大学附属第二医院行胶囊内镜检查的患者122例,采用随机数字表法将其分为试验组63例和对照组59例,试验组即吞服胶囊后随时可以蹲厕,对照组如需如厕采取坐便。比较2组患者GTT、小肠转运时间、CER和诊断率的区别。结果试验组和对照组患者在性别、年龄、住院情况等方面差异无统计学意义。试验组患者CER显著高于对照组(92.06%vs 79.66%),差异有统计学意义(P=0.048)。试验组患者中位GTT显著少于对照组(26.7 vs 45.6 min),差异有统计学意义(P=0.027)。两组患者在小肠转运时间和诊断率上差异无统计学意义。结论行胶囊内镜检查患者采用蹲厕行为能减少胶囊在胃内转运时间,增加全小肠检查率。