7/27/2019 cardiac.docx
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Main Idea:
The author proposed nonlinear analysis for characterizing
cardiac and non-cardiac diseases of the
Autonomic Nervous System based on Heart Rate Variability (HRV).
Three nonlinear HRV parameters are
considered: 1) Approximate Entropy (ApEn); 2) Sample Entropy
(SampEn); 3) Symbolic Entropy (SE).
Major Issues:
1. Performance comparison and explanation of each nonlinear
techniques is required. For example,in what cases that the ApEn is
give more precise results compare to the SampEn or other
nonlinear
method.
2. In this thesis, the author does not offer a discussion of
values/parameters that are used for theanalysis (i.e., chapter
IV-Implementation of ApEn and SampEn). There is no discussion why
and how
the author uses those values for algorithm implementation. A
comparison of different
values/parameters could be made to see the optimal solution for
characterizing different cardiac
and non-cardiac diseases of Autonomic Nervous system.
3. The author does not explain the details ofhow the author did
the analysis of FFT andAutoregressive model to analyze power
spectral. For example, how the author determines
thevalues/parameters for the modeling. The same issues also applied
for the derivation of Correlation
Dimension.
4. The author does not offer a balanced discussion of the
thesis. The discussion should also explain notonly from the medical
point of view, but also from mathematical point of view. For
example, there is
no any explanation about how the authorderive the Power Spectral
Density distribution and the
Spectral Entropy using HRV.
5. The author stated that no studies have been addressed the
problem of detecting the impact ofThyroid on ANS and impact of
Depression on ANS However, it seems contradicted because most
of
the algorithm implementations used in this thesis are based on
the previous work. (e.g., 101, 102,
105, etc].
6. There is no explanation about whats the current system for
detecting or characterizing whether asubject has cardiac or
non-cardiac diseases. Whats the problem of the current system and
whats
this thesis trying to solve.
Minor:
Chapter I
1. Page 18 Section 1.8 MotivationThe motivation of this thesis
was not clearly stated in this section. It would be better if the
author
clearly describe clearly what the contribution of this thesis is
and relate it to the problem definition.
2. Page 19 Section 1.9 Problem DefinitionThe problem definition
of this thesis was not clearly described. For example, what is the
existed
problems, whats the current methodology for characterizing the
subjects that are suffering from
Cardiac and non-cardiac diseases.
3. Page 20 Section 1.10There is no any details explanation in
the later chapter to discuss the objectives of the research as
stated in point 2 to 6.
