1,284 research outputs found
Effect of Respiration on the Characteristic Ratios of Oscillometric Pulse Amplitude Envelope in Blood Pressure Measurement
Systolic and diastolic blood pressures (BPs) are important physiological parameters for disease diagnosis. Systolic and diastolic characteristic ratios derived from oscillometric pulse waveform have been widely used to estimate automated non-invasive BPs in oscillometric BP measurement devices. The oscillometric pulse waveform is easily influenced by respiration, which may cause variability to the characteristic ratios and subsequently BP measurement. This study quantitatively investigated how respiration patterns (i.e., normal breathing and deep breathing) affect the systolic and diastolic characteristic ratios. The study was performed with clinical data collected from 39 healthy subjects, and each subject conducted BP measurements during normal and deep breathings. Analytical results showed that the systolic characteristic ratio increased significantly from 0.52 ± 0.13 under normal breathing to 0.58 ± 0.14under deep breathing (p < 0.05), and the diastolic characteristic ratio was not significantly affected from 0.75 ± 0.12 under normal breathing to 0.76 ± 0.13 under deep breathing (p = 0.48). In conclusion, deep breathing significantly affected the systolic characteristic ratio, suggesting that automated oscillometric BP device which is validated under resting condition should be strictly used for measurements under resting condition
Rare diseases in developing countries: Insights from China's collaborative network
Rare diseases (RDs) are complex conditions and a worldwide healthcare challenge. The healthcare policymakers in developing countries lack templates from countries at the same level of development. This article introduced and discussed the combination of top‐down strategies and bottom‐up interventions in addressing RDs in a developing country, China, as an example. The government leads the formulation of laws, policies, and guidance to coordinate national resources, while local authorities and nongovernment organisations (NGOs) are responsible for policy localisation and complement policy gaps. This article may inspire other developing countries of improving RD healthcare
Zero-Rate Thresholds and New Capacity Bounds for List-Decoding and List-Recovery
In this work we consider the list-decodability and list-recoverability of arbitrary q-ary codes, for all integer values of q ? 2. A code is called (p,L)_q-list-decodable if every radius pn Hamming ball contains less than L codewords; (p,?,L)_q-list-recoverability is a generalization where we place radius pn Hamming balls on every point of a combinatorial rectangle with side length ? and again stipulate that there be less than L codewords.
Our main contribution is to precisely calculate the maximum value of p for which there exist infinite families of positive rate (p,?,L)_q-list-recoverable codes, the quantity we call the zero-rate threshold. Denoting this value by p_*, we in fact show that codes correcting a p_*+? fraction of errors must have size O_?(1), i.e., independent of n. Such a result is typically referred to as a "Plotkin bound." To complement this, a standard random code with expurgation construction shows that there exist positive rate codes correcting a p_*-? fraction of errors. We also follow a classical proof template (typically attributed to Elias and Bassalygo) to derive from the zero-rate threshold other tradeoffs between rate and decoding radius for list-decoding and list-recovery.
Technically, proving the Plotkin bound boils down to demonstrating the Schur convexity of a certain function defined on the q-simplex as well as the convexity of a univariate function derived from it. We remark that an earlier argument claimed similar results for q-ary list-decoding; however, we point out that this earlier proof is flawed
Tight Bounds on List-Decodable and List-Recoverable Zero-Rate Codes
In this work, we consider the list-decodability and list-recoverability of
codes in the zero-rate regime. Briefly, a code is
-list-recoverable if for all tuples of input lists
with each and the number of
codewords such that for at most
choices of is less than ; list-decoding is the special case of
. In recent work by Resch, Yuan and Zhang~(ICALP~2023) the zero-rate
threshold for list-recovery was determined for all parameters: that is, the
work explicitly computes with the property that for all
(a) there exist infinite families positive-rate
-list-recoverable codes, and (b) any
-list-recoverable code has rate . In fact, in the
latter case the code has constant size, independent on . However, the
constant size in their work is quite large in , at least
.
Our contribution in this work is to show that for all choices of and
with , any -list-recoverable code must
have size , and furthermore this upper bound is
complemented by a matching lower bound . This
greatly generalizes work by Alon, Bukh and Polyanskiy~(IEEE Trans.\ Inf.\
Theory~2018) which focused only on the case of binary alphabet (and thus
necessarily only list-decoding). We remark that we can in fact recover the same
result for and even , as obtained by Alon, Bukh and Polyanskiy: we
thus strictly generalize their work.Comment: Abstract shortened to meet the arXiv requiremen
Optimal Resource Allocation for Multi-UAV Assisted Visible Light Communication
In this paper, the optimization of deploying unmanned aerial vehicles (UAVs)
over a reconfigurable intelligent surfaces (RISs)-assisted visible light
communication (VLC) system is studied. In the considered model, UAVs are
required to simultaneously provide wireless services as well as illumination
for ground users. To meet the traffic and illumination demands of the ground
users while minimizing the energy consumption of the UAVs, one must optimize
UAV deployment, phase shift of RISs, user association and RIS association. This
problem is formulated as an optimization problem whose goal is to minimize the
transmit power of UAVs via adjusting UAV deployment, phase shift of RISs, user
association and RIS association. To solve this problem, the original
optimization problem is divided into four subproblems and an alternating
algorithm is proposed. Specifically, phases alignment method and semidefinite
program (SDP) algorithm are proposed to optimize the phase shift of RISs. Then,
the UAV deployment optimization is solved by the successive convex
approximation (SCA) algorithm. Since the problems of user association and RIS
association are integer programming, the fraction relaxation method is adopted
before using dual method to find the optimal solution. For simplicity, a greedy
algorithm is proposed as an alternative to optimize RIS association. The
proposed two schemes demonstrate the superior performance of 34:85% and 32:11%
energy consumption reduction over the case without RIS, respectively, through
extensive numerical study
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