Objective: Determine the occurrence rate of cochlear implant (CI) electrode tip fold-over and electrode scalar deviation as reported in patient cases with different commercial electrode types. Data-sources: PubMed sea...Objective: Determine the occurrence rate of cochlear implant (CI) electrode tip fold-over and electrode scalar deviation as reported in patient cases with different commercial electrode types. Data-sources: PubMed search for identifying peer-reviewed articles published till 2018 on CI electrode tip fold-over and scalar deviation. Key-words for searching were “Cochlear electrode tip fold-over”,“Cochlear electrode scalar position” and “Cochlear electrode scalar location”. Articles-selection: Only if electrode related issues were investigated in patient cases. 38 articles met the inclusion-criteria. Results: 13 articles on electrode tip fold-over issue covering 3177 implanted ears, out of which 50 ears were identified with electrode tip fold-over with an occurrence rate of 1.57%. Out of 50 ears, 43 were implanted with pre-curved electrodes and the remaining 7 with lateral-wall electrodes. One article reported on both tip fold-over and scalar deviation. 26 articles reported on the electrode scalar deviation covering an overall number of 2046 ears out of which, 458 were identified with electrode scalar deviation at a rate of 22.38%. After removing the studies that did not report on the number of electrodes per electrode type, it was 1324 ears implanted with pre-curved electrode and 507 ears with lateral-wall electrode. Out of 1324 pre-curved electrode implanted ears, 424 were reported with scalar deviation making an occurrence rate of 32%. Out of 507 lateral-wall electrode implanted ears, 43 were associated with scalar deviation at an occurrence rate of 6.7%. Conclusion: This literature review revealing the fact of higher rate of electrode insertion trauma associated with pre-curved electrode type irrespective of CI brand is one step closer to obsolete it from the clinical practice in the interest of patient's cochlear health.展开更多
Due to the limited resources and budgets in many real-life projects, it is unaffordable to use full factorial experimental designs and thus fractional factorial(FF) designs are used instead. The aliasing of factorial ...Due to the limited resources and budgets in many real-life projects, it is unaffordable to use full factorial experimental designs and thus fractional factorial(FF) designs are used instead. The aliasing of factorial effects is the price we pay for using FF designs and thus some significant effects cannot be estimated. Therefore, some additional observations(runs) are needed to break the linages among the factorial effects. Folding over the initial FF designs is one of the significant approaches for selecting the additional runs. This paper gives an in-depth look at fold-over techniques via the following four significant contributions. The first contribution is on discussing the adjusted switching levels foldover technique to overcome the limitation of the classical one. The second contribution is on presenting a comparison study among the widely used fold-over techniques to help experimenters to recommend a suitable fold-over technique for their experiments by answering the following two fundamental questions:Do these techniques dramatically lessen the confounding of the initial designs, and do the resulting combined designs(combining initial design with its fold-over) via these techniques have considerable difference from the optimality point of view considering the markedly different searching domains in each technique? The optimality criteria are the aberration, confounding, Hamming distance and uniformity. Many of these criteria are given in sequences(patterns) form, which are inconvenient and costly to represent and compare, especially when the designs have many factors. The third innovation is on developing a new criterion(dictionary cross-entropy loss) to simplify the existing criteria fromsequence to scalar. The new criterion leads to a more straightforward and easy comparison study. The final contribution is on establishing a general framework for the connections between initial designs and combined designs based on any fold-over technique.展开更多
Six categories of systematic 2n-(n-k) designs derivable from the full 2k factorial experiment by the interactions-main effects assignment are available for carrying out 2n-(n-k) factorial experiments sequentially run ...Six categories of systematic 2n-(n-k) designs derivable from the full 2k factorial experiment by the interactions-main effects assignment are available for carrying out 2n-(n-k) factorial experiments sequentially run after the other such that main effects are protected against the linear/quadratic time trend and/or such that the number of factor level changes (i.e. cost) between the runs is minimal. Three of these six categories are of resolution at least III and three are of resolution at least IV. The three categories of designs within each resolution are: 1) minimum cost 2n-(n-k) designs, 2) minimum cost linear trend free 2n-(n-k) designs and 3) minimum cost linear and quadratic trend free 2n-(n-k) designs. This paper characterizes these six categories and documents their differences with regard to either time trend resistance of factor effects and/or the number of factor level changes. The paper introduces the last category of systematic 2n-(n-k) designs (i.e. the sixth) for the purpose of extending the design resolution from III into IV and also for raising the level of protection of main effects from the linear time trend into the quadratic, where a catalog of minimum cost linear and quadratic trend free 2n-(n-k) designs (of resolution at least IV) will be proposed. The paper provides for each design in any of the six categories: 1) the sequence of its runs in minimum number of factor level changes 2) the defining relation or its 2n-(n-k) alias structure and 3) the k independent generators needed for sequencing the 2n-(n-k) runs by the generalized foldover scheme. A comparison among these six categories of designs reveals that when the polynomial degree of the time trend increases from linear into quadratic and/or when the design’s resolution increases from III to IV, the number of factor level changes between the 2n-(n-k) runs increases. Also as the number of factors (i.e. n) increases, the design’s resolution decreases.展开更多
提出了一种新的可用于RoF(Radio over Fiber)系统的六倍频毫米波信号的产生方法,通过设置两级联MZM调制器各自的偏置状态,并联合控制它们之间的光载波时延以及驱动信号间的相位差,来产生六倍频毫米波信号。在毫米波信号模块产生的基础上...提出了一种新的可用于RoF(Radio over Fiber)系统的六倍频毫米波信号的产生方法,通过设置两级联MZM调制器各自的偏置状态,并联合控制它们之间的光载波时延以及驱动信号间的相位差,来产生六倍频毫米波信号。在毫米波信号模块产生的基础上,针对两种不同的数据加载方式,构建相应的下行传输链路,对光毫米波传输特性进行了理论分析和仿真验证。展开更多
文摘Objective: Determine the occurrence rate of cochlear implant (CI) electrode tip fold-over and electrode scalar deviation as reported in patient cases with different commercial electrode types. Data-sources: PubMed search for identifying peer-reviewed articles published till 2018 on CI electrode tip fold-over and scalar deviation. Key-words for searching were “Cochlear electrode tip fold-over”,“Cochlear electrode scalar position” and “Cochlear electrode scalar location”. Articles-selection: Only if electrode related issues were investigated in patient cases. 38 articles met the inclusion-criteria. Results: 13 articles on electrode tip fold-over issue covering 3177 implanted ears, out of which 50 ears were identified with electrode tip fold-over with an occurrence rate of 1.57%. Out of 50 ears, 43 were implanted with pre-curved electrodes and the remaining 7 with lateral-wall electrodes. One article reported on both tip fold-over and scalar deviation. 26 articles reported on the electrode scalar deviation covering an overall number of 2046 ears out of which, 458 were identified with electrode scalar deviation at a rate of 22.38%. After removing the studies that did not report on the number of electrodes per electrode type, it was 1324 ears implanted with pre-curved electrode and 507 ears with lateral-wall electrode. Out of 1324 pre-curved electrode implanted ears, 424 were reported with scalar deviation making an occurrence rate of 32%. Out of 507 lateral-wall electrode implanted ears, 43 were associated with scalar deviation at an occurrence rate of 6.7%. Conclusion: This literature review revealing the fact of higher rate of electrode insertion trauma associated with pre-curved electrode type irrespective of CI brand is one step closer to obsolete it from the clinical practice in the interest of patient's cochlear health.
基金supported by the Beijing Normal University-Hong Kong Baptist University United International College under Grant Nos.R201810,R201912 and R202010the Zhuhai Premier Discipline Grant。
文摘Due to the limited resources and budgets in many real-life projects, it is unaffordable to use full factorial experimental designs and thus fractional factorial(FF) designs are used instead. The aliasing of factorial effects is the price we pay for using FF designs and thus some significant effects cannot be estimated. Therefore, some additional observations(runs) are needed to break the linages among the factorial effects. Folding over the initial FF designs is one of the significant approaches for selecting the additional runs. This paper gives an in-depth look at fold-over techniques via the following four significant contributions. The first contribution is on discussing the adjusted switching levels foldover technique to overcome the limitation of the classical one. The second contribution is on presenting a comparison study among the widely used fold-over techniques to help experimenters to recommend a suitable fold-over technique for their experiments by answering the following two fundamental questions:Do these techniques dramatically lessen the confounding of the initial designs, and do the resulting combined designs(combining initial design with its fold-over) via these techniques have considerable difference from the optimality point of view considering the markedly different searching domains in each technique? The optimality criteria are the aberration, confounding, Hamming distance and uniformity. Many of these criteria are given in sequences(patterns) form, which are inconvenient and costly to represent and compare, especially when the designs have many factors. The third innovation is on developing a new criterion(dictionary cross-entropy loss) to simplify the existing criteria fromsequence to scalar. The new criterion leads to a more straightforward and easy comparison study. The final contribution is on establishing a general framework for the connections between initial designs and combined designs based on any fold-over technique.
文摘Six categories of systematic 2n-(n-k) designs derivable from the full 2k factorial experiment by the interactions-main effects assignment are available for carrying out 2n-(n-k) factorial experiments sequentially run after the other such that main effects are protected against the linear/quadratic time trend and/or such that the number of factor level changes (i.e. cost) between the runs is minimal. Three of these six categories are of resolution at least III and three are of resolution at least IV. The three categories of designs within each resolution are: 1) minimum cost 2n-(n-k) designs, 2) minimum cost linear trend free 2n-(n-k) designs and 3) minimum cost linear and quadratic trend free 2n-(n-k) designs. This paper characterizes these six categories and documents their differences with regard to either time trend resistance of factor effects and/or the number of factor level changes. The paper introduces the last category of systematic 2n-(n-k) designs (i.e. the sixth) for the purpose of extending the design resolution from III into IV and also for raising the level of protection of main effects from the linear time trend into the quadratic, where a catalog of minimum cost linear and quadratic trend free 2n-(n-k) designs (of resolution at least IV) will be proposed. The paper provides for each design in any of the six categories: 1) the sequence of its runs in minimum number of factor level changes 2) the defining relation or its 2n-(n-k) alias structure and 3) the k independent generators needed for sequencing the 2n-(n-k) runs by the generalized foldover scheme. A comparison among these six categories of designs reveals that when the polynomial degree of the time trend increases from linear into quadratic and/or when the design’s resolution increases from III to IV, the number of factor level changes between the 2n-(n-k) runs increases. Also as the number of factors (i.e. n) increases, the design’s resolution decreases.
文摘提出了一种新的可用于RoF(Radio over Fiber)系统的六倍频毫米波信号的产生方法,通过设置两级联MZM调制器各自的偏置状态,并联合控制它们之间的光载波时延以及驱动信号间的相位差,来产生六倍频毫米波信号。在毫米波信号模块产生的基础上,针对两种不同的数据加载方式,构建相应的下行传输链路,对光毫米波传输特性进行了理论分析和仿真验证。
