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951.
A smartphone‐based U‐Healthcare system for real‐time monitoring of acute myocardial infarction 下载免费PDF全文
Jaehyo Jung Jihoon Lee Jihwan Lee Youn Tae Kim 《International Journal of Communication Systems》2015,28(18):2311-2325
In recent years, medical service has been evolving from systems designed around centralized hospitals to Ubiquitous Healthcare (U‐Healthcare). U‐Healthcare system can facilitate real‐time monitoring of patient states, and can provide medical checkups and management whenever and wherever the medical staff deems necessary. U‐Healthcare services can provide chronic condition monitoring in the early stages of diseases and help execute decisive medical action in emergencies. However, thus far, the application of U‐Healthcare systems has been limited to diseases such as obesity, diabetes, etc. Acute myocardial infarction (AMI) is among the most critical chronic diseases and requires early detection and treatment. In this paper, we propose an AMI diagnostic software technique and protocol that can support real‐time communication between the patient and medical personnel. Our monitoring and diagnostic system has been developed using a protocol based on ISO/IEEE 11073. When data is transferred from the patient's smartphone to a server in hospital, the medical personnel consult the patient's biosensor data to determine the status of the relevant disease and provide appropriate medical service. The relevant information is sent back to the patient's smartphone through a wireless network, and patients can view their data in graphical format through their smartphone. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
952.
Surface Chemistry of Vitamin: Pyridoxal 5′‐Phosphate (Vitamin B6) as a Multifunctional Compound for Surface Functionalization 下载免费PDF全文
Jung Seung Lee Kyuri Kim Kihong Lee Joseph P. Park Kisuk Yang Seung‐Woo Cho Haeshin Lee 《Advanced functional materials》2015,25(30):4754-4760
Vitamins are non‐toxic compounds that perform a variety of biological functions and also available in a large quantity. Other than the usage as food supplements, few attempts have been made to use them as functional materials. In this study, we report that vitamin B6, pyridoxal 5′‐phosphate (PLP), is a multi‐functional molecule for oxide surface chemistry. PLP‐immobilized surfaces exhibit superhydrophilicity and even hemophilicity, enhancing proliferation, migration, and differentiation of mammalian cells. Unlike existing molecules used so far in surface modification, PLP has an intrinsic chemical reactivity toward biomacromolecules due to the presence of the aldehyde group. In fact, RGD peptide is covalently tethered onto PLP surfaces directly in one step without any chemical activation. Furthermore, PLP‐functionalized implant device showed rapid bone healing. As vitamin B6 is a FDA approved molecule for human usage, the surface chemistry of vitamin B6 potentially allows a fast route for surface functionalized medical devices into clinic. 相似文献
953.
Seung‐Kyun Kang Suk‐Won Hwang Sooyoun Yu Jung‐Hun Seo Elise A. Corbin Jiho Shin Dae Seung Wie Rashid Bashir Zhenqiang Ma John A. Rogers 《Advanced functional materials》2015,25(12):1789-1797
Biodegradable substrates and encapsulating materials play critical roles in the development of an emerging class of semiconductor technology, generally referred as “transient electronics”, whose key characteristic is an ability to dissolve completely, in a controlled manner, upon immersion in ground water or biofluids. The results presented here introduce the use of thin foils of Mo, Fe, W, or Zn as biodegradable substrates and silicate spin‐on‐glass (SOG) materials as insulating and encapsulating layers, with demonstrations of transient active (diode and transistor) and passive (capacitor and inductor) electronic components. Complete measurements of electrical characteristics demonstrate that the device performance can reach levels comparable to those possible with conventional, nontransient materials. Dissolution kinetics of the foils and cytotoxicity tests of the SOG yield information relevant to use in transient electronics for temporary biomedical implants, resorbable environmental monitors, and reduced waste consumer electronics. 相似文献
954.
Vitamins: Surface Chemistry of Vitamin: Pyridoxal 5′‐Phosphate (Vitamin B6) as a Multifunctional Compound for Surface Functionalization (Adv. Funct. Mater. 30/2015) 下载免费PDF全文
Jung Seung Lee Kyuri Kim Kihong Lee Joseph P. Park Kisuk Yang Seung‐Woo Cho Haeshin Lee 《Advanced functional materials》2015,25(30):4745-4745
955.
Organic Electronics: Self‐Assembled,Millimeter‐Sized TIPS‐Pentacene Spherulites Grown on Partially Crosslinked Polymer Gate Dielectric (Adv. Funct. Mater. 24/2015) 下载免费PDF全文
Hocheon Yoo Hyun Ho Choi Tae Joo Shin Taiuk Rim Kilwon Cho Sungjune Jung Jae‐Joon Kim 《Advanced functional materials》2015,25(24):3795-3795
956.
“Multipoint Force Feedback” Leveling of Massively Parallel Tip Arrays in Scanning Probe Lithography 下载免费PDF全文
Hanaul Noh Goo‐Eun Jung Sukhyun Kim Seong‐Hun Yun Ahjin Jo Se‐Jong Kahng Nam‐Joon Cho Sang‐Joon Cho 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(35):4526-4531
Nanoscale patterning with massively parallel 2D array tips is of significant interest in scanning probe lithography. A challenging task for tip‐based large area nanolithography is maintaining parallel tip arrays at the same contact point with a sample substrate in order to pattern a uniform array. Here, polymer pen lithography is demonstrated with a novel leveling method to account for the magnitude and direction of the total applied force of tip arrays by a multipoint force sensing structure integrated into the tip holder. This high‐precision approach results in a 0.001° slope of feature edge length variation over 1 cm wide tip arrays. The position sensitive leveling operates in a fully automated manner and is applicable to recently developed scanning probe lithography techniques of various kinds which can enable “desktop nanofabrication.” 相似文献
957.
Young-Gon Lee Jun-Gyu Park Chang-Woo Lee Jae-Pil Jung 《Metals and Materials International》2011,17(1):117-121
The electroplating characteristics and deposition layer of a Sn-Bi eutectic alloy applicable to low-temperature soldering
were investigated. A methane sulphonate electrolyte was fabricated and the current density was focused in order to achieve
an eutectic Sn-Bi composition. The electroplating characteristics, including the polarization curve and deposition thickness
with plating time, were also studied. As experimental results, a polarization curve showed a Sn-Bi codeposition occurred under
a −0.5 V electropotential. The Bi content in the Sn-Bi deposit decreased with an increasing current density, such as 99.42
wt.% for −10 mA/cm2 and 42.27 wt.% for −40 mA/cm2. The thickness of the electroplated layer increased with the plating time, while a relatively uniform thickness was obtained
in a short plating time, such as less than 40 min. The eutectic deposition of Sn-58.2 wt.%Bi was successfully fabricated by
plating at −30 mA/cm2 for 30 min. 相似文献
958.
Seong-Ho Choi Dong-Won Jung Sung-Ook Yoon Soon Park Eun-Suok Oh Junbom Kim 《Metals and Materials International》2011,17(5):811-816
To enhance the performance of a polymer electrolyte membrane fuel cell (PEMFC), a Pt catalyst was supported on carbon nanotubes
(CNTs) and the optimum content of Nafion ionomer in the Pt/CNT electrode was examined by cell performance tests, cyclic voltammetry,
and electrochemical impedance spectroscopy. The amount of the Pt catalyst supported on the CNTs was 34 wt.%. The Nafion content
significantly changed the protonic and electronic conductivities as well as the mass transfer properties. As such, the performance
of the cell was highly dependent on the content of Nafion ionomer. The results of the cell performance tests revealed that
the optimum content of Nafion ionomer in the Pt/CNT electrode was about 20 wt.%. 相似文献
959.
Yeon-Seung Jung Young-Kook Lee David K. Matlock Martin C. Mataya 《Metals and Materials International》2011,17(4):553-556
Tensile tests were used to investigate the effect of grain size on the strain-induced martensitic transformation start temperature
in metastable austenitic steel with special attention to ultrafine grain size. The austenite grains were refined to submicron
size by the strain-induced martensite and its reverse transformations (SIMRT), which occurred during a conventional cold rolling
and annealing process. The start temperature of the straininduced martensitic transformation was linearly lowered with a decrease
in austenite grain size, even down to submicron grain sizes. This result is due to the decrease in grain size causing an increase
in the temperature dependency of the strain-induced martensitic transformation and higher austenite stability brought about
by grain refinement. 相似文献
960.
Vibration control of smart hull structure with optimally placed piezoelectric composite actuators 总被引:1,自引:0,他引:1
Active vibration control to suppress structural vibration of the smart hull structure was investigated based on optimized actuator configurations. Advanced anisotropic piezoelectric composite actuator, Macro-Fiber Composite (MFC), was used for the vibration control. Governing equations of motion of the smart hull structure including MFC actuators were obtained using the Donnell-Mushtari shell theory and Lagrange's equation. The Rayleigh-Ritz method was used to obtain the dynamic characteristics of the smart hull structure. Experimental modal tests were conducted to verify the proposed mathematical model. In order to achieve high control performance, optimal locations and directions of the MFC actuators were determined by genetic algorithm. Optimal control algorithm was then synthesized to suppress structural vibration of the proposed smart hull structure and experimentally implemented to the system. Active vibration control performances were evaluated under various modes excitations. Vibration tests revealed that optimal configurations of MFC actuators improved the control performance of the smart hull structure in case of the limited number of actuators available. 相似文献