• Title/Summary/Keyword: Medical electronics

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Quantitative Sensory Test: Normal Range in Korean Adults and Application to Diabetic Polyneuropathy (정량적 감각 검사: 한국인에서의 연령별 정상 범위 및 당뇨병성 다발신경병증에서의 유용성 평가)

  • Kim, Su-Hyun;Kim, Sung-Min;Ahn, Suk-Won;Hong, Yoon-Ho;Park, Kyung-Seok;Sung, Jung-Joon;Lee, Kwang-Woo
    • Annals of Clinical Neurophysiology
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    • v.12 no.1
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    • pp.21-26
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    • 2010
  • Background: Although quantitative sensory test (QST) is being used with increasing frequency for measuring sensory thresholds in clinical practice and epidemiologic studies, there has been no age-matched normative data in Korean adults. The objective of this study is to evaluate the value of QST in diabetic polyneuropathy with normal range in Korean adults. Methods: The Computer Aided Sensory Examination IV 4,2 (WR Medical Electronics Co., Stillwater, Minnesota, U.S.A.), with 4,2,1 stepping algorithm was used to determine vibration and cold perception threshold in 70 normal controls and 19 patients with diabetic polyneuropathy aged from 21 to 79 years. The data were used to define age-matched upper and lower normal limits and normal range of side to side difference. We also evaluated the duration of diabetes, serum HbA1C level, and findings of nerve conduction study (NCS) and QST in patients with diabetic polyneuropathy. Results: In normal adults, sensory thresholds slightly increased with age, and a slight side-to-side difference was observed. The diagnostic sensitivity of QST was not higher than NCS in patients with diabetic polyneuropathy (36.8% vs. 42.1%, p=0.716), especially among elderly patients. Conclusions: QST might be used as a complementary test for NCS in the diagnosis of diabetic polyneuropathy. Although the QST is a simple method for the evaluation of peripheral nerve function, there are some limitations. Most of all, because the QST measuring is dependent on the subjective response of patients, the degree of concentration and cooperation of the patients can significantly affect the result. And thus, attention should be paid during the interpretation of QST results in patients with peripheral neuropathy.

Characteristics of Autonomic Nervous System Responses Induced by Anger in Individuals with High Trait Anxiety (분노유발에 따른 특성불안자의 자율신경계 반응 특성)

  • Eum, Young-Ji;Jang, Eun-Hye;Sohn, Jin-Hun
    • Science of Emotion and Sensibility
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    • v.20 no.3
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    • pp.169-180
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    • 2017
  • Individuals with high trait anxiety try to suppress their anger expression, thus there are limits in measuring their anger using subjective behavioral evaluation. In order to overcome this limitation, this study attempted to identify the difference in the autonomic nervous system responses induced by anger in individuals with high trait anxiety. Participants were divided into two groups, anxiety and control groups. Electrocardiogram (ECG), respiration (RESP), electrodermal activity (EDA), and skin temperature (SKT) were measured while participants were presented with an anger-inducing stimulus. Heart rate (HR), standard deviation of NN interval (SDNN), root mean square of successive difference (RMSSD), low frequency (LF), high frequency (HF), LF/HF ratio, respiration rate (RR), skin conductance level (SCL), and maximum skin temperature (maxSKT) were calculated before and after presenting the stimulus. Anxiety group reported greater anger by the anger-inducing stimulus compared to the control group. Anxiety group also showed significant increase in SDNN and LF, and decrease in HF, LF/HF ratio, and RR. These results suggest that the autonomic nervous system responses may be used as objective indicators of anger experiences in individuals with high trait anxiety.

Factors Related to the Intention of Participation in a Worksite Smoking Cessation Program (근로자의 금연프로그램 참가의도와 관련된 요인)

  • Kim, Sung-Ah;Kam, Sin;Yeh, Min-Hae;Park, Ki-Su;Oh, Hee-Sook;Son, Jae-Hee
    • Journal of Preventive Medicine and Public Health
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    • v.32 no.3
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    • pp.297-305
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    • 1999
  • Objectives: This study was conducted to evaluate factors related to the intention of participation in a worksite smoking cessation program. Methods: To explain the health behavior of participating intention in a worksite smoking cessation program, the health belief model(HBM) was used as study model, and 144 self-administered questionnaires were completed by electronic company workers. Variables of the health belief model were composed of perceived susceptibility to smokinginduced disease, perceived severity of smoking-induced disease, economical gain as perceived benefit of smoking cessation, and nicotine dependency as perceived barrier of smoking cessation. Variables of sociodemographics, smoking status, knowledge about adverse health effects of smoking, and cues to smoking cessation were used as modifying factors. Results: Perceived severity(POR=1.99, 95% CI: 1.03-3.83), perceived benefit(POR=2.11, 95% CI: 1.07-4.17), and perceived barrier(POR=0.29, 95% CI: 0.11-0.76) were significant variables to the intention of participation in a worksite smoking cessation program in the logistic regression analysis. The perceived severity was significantly affected by knowledge about adverse health effects of smoking(POR=2.17, 95% CI: 1.23-3.84). The perceived barrier was significantly affected by education level(POR=3.66, 95% CI: 1.17-11.44), age to first cigarette (POR=0.32, 95% CI: 0.10-0.98), pack-years(POR=5.47, 95% CI: 2.37-12.61). To the Perceived benefit, the model was not fitted. Conclusion: Our results found that counterplans improving the knowledge about adverse health effects of smoking, preventing early smoking, and decreasing smoking amount should be considered for an effective smoking ban policy.

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Virtual core point detection and ROI extraction for finger vein recognition (지정맥 인식을 위한 가상 코어점 검출 및 ROI 추출)

  • Lee, Ju-Won;Lee, Byeong-Ro
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.10 no.3
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    • pp.249-255
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    • 2017
  • The finger vein recognition technology is a method to acquire a finger vein image by illuminating infrared light to the finger and to authenticate a person through processes such as feature extraction and matching. In order to recognize a finger vein, a 2D mask-based two-dimensional convolution method can be used to detect a finger edge but it takes too much computation time when it is applied to a low cost micro-processor or micro-controller. To solve this problem and improve the recognition rate, this study proposed an extraction method for the region of interest based on virtual core points and moving average filtering based on the threshold and absolute value of difference between pixels without using 2D convolution and 2D masks. To evaluate the performance of the proposed method, 600 finger vein images were used to compare the edge extraction speed and accuracy of ROI extraction between the proposed method and existing methods. The comparison result showed that a processing speed of the proposed method was at least twice faster than those of the existing methods and the accuracy of ROI extraction was 6% higher than those of the existing methods. From the results, the proposed method is expected to have high processing speed and high recognition rate when it is applied to inexpensive microprocessors.

Principles and Current Trends of Neural Decoding (뉴럴 디코딩의 원리와 최신 연구 동향 소개)

  • Kim, Kwangsoo;Ahn, Jungryul;Cha, Seongkwang;Koo, Kyo-in;Goo, Yong Sook
    • Journal of Biomedical Engineering Research
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    • v.38 no.6
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    • pp.342-351
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    • 2017
  • The neural decoding is a procedure that uses spike trains fired by neurons to estimate features of original stimulus. This is a fundamental step for understanding how neurons talk each other and, ultimately, how brains manage information. In this paper, the strategies of neural decoding are classified into three methodologies: rate decoding, temporal decoding, and population decoding, which are explained. Rate decoding is the firstly used and simplest decoding method in which the stimulus is reconstructed from the numbers of the spike at given time (e. g. spike rates). Since spike number is a discrete number, the spike rate itself is often not continuous and quantized, therefore if the stimulus is not static and simple, rate decoding may not provide good estimation for stimulus. Temporal decoding is the decoding method in which stimulus is reconstructed from the timing information when the spike fires. It can be useful even for rapidly changing stimulus, and our sensory system is believed to have temporal rather than rate decoding strategy. Since the use of large numbers of neurons is one of the operating principles of most nervous systems, population decoding has advantages such as reduction of uncertainty due to neuronal variability and the ability to represent a stimulus attributes simultaneously. Here, in this paper, three different decoding methods are introduced, how the information theory can be used in the neural decoding area is also given, and at the last machinelearning based algorithms for neural decoding are introduced.

Fabrication and Evaluation of the Super Thin-Type EM Wave Absorber for Suppressing EM Noises in 2.4 GHz Band (2.4 GHz 대역용 불요전자파 억제용 초박형 전파흡수체의 제작 및 평가)

  • Kim, Dong Il;Kwak, Hyun Soo;Joo, Yang Ick;Park, Soo Hoon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.3
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    • pp.500-506
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    • 2015
  • In this paper, we designed and fabricated the EM wave absorber consisted of Sendust for suppressing EM wave noise PCB in ISM (Industrial, Scientific and Medical) band of 2.4 GHz. We fabricated several samples with different composition ratios of some kinds of Sendust to CPE (Chlorinated Ploy-ethylene) as a binder, and it was confirmed that the optimum composition ratio of absorbing materials was Flaked Sendust : CPE = 72.5 : 27.5 wt.%.. The absorbing abilities were simulated by changing the thickness and the measured material constants of EM wave absorber. The measured absorption abilities were analyzed and compared with the simulated ones. As a result, the simulated results agree well with the measured ones, and the developed EM wave absorber with extremely thin thickness of 0.6 mm has absorption ability of 5.4 dB at 2.4 GHz is excellent one. The thin type EM wave absorber can be applied for suppressing and absorbing electromagnetic noises from information and communication equipments.

A Study on the Technology Development of User-based Home Automation Service (사용자 위치기반 홈오토메이션 서비스 기술 개발에 관한 연구)

  • Lee, Jung-Gi;Lee, Yeong-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.3
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    • pp.327-332
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    • 2017
  • As Internet of Things (IoT) technology advances, there is a growing demand for location-based services (LBSs) to identify users' mobility and identity. The initial LBS system was mainly used to measure position information by measuring the phase of a signal transmitted from a global positioning system (GPS) satellite or by measuring distance to a satellite by tracking the code of a carrier signal. However, the use of GPS satellites is ineffective, because it is difficult to receive satellite signals indoors. Therefore, research on wireless communications systems like ultra-wide band (UWB), radio frequency identification (RFID), and ZigBee are being actively pursued for location recognition technology that can be utilized in an indoor environment. In this paper, we propose an LBS system that includes the 2.45GHz band for chirp spread spectrum (CSS), and the 3.1-10.6GHz band and the 250-750MHz bands for UWB using the IEEE 802.15.4a standard for low power-based location recognition. As a result, we confirmed that the 2.45GHz Industrial, Scientific and Medical (ISM) band RF transceiver and the ranging function can be realized in the hardware and has 0dBm output power.

The Mechanical Sensitivity at Interfaces between Bone and Interbody Cage of Lumbar Spine Segments (Lumbar spine 의 뼈와 Interbody cage의 접촉면에서 기계공학적 민감성 고찰)

  • Kim Y.
    • Journal of Biomedical Engineering Research
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    • v.21 no.3 s.61
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    • pp.295-301
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    • 2000
  • It is known that among many factors, relative micromotion at bone/implant interfaces can hinder bone ingrowth into surface pores of an implant. Loading conditions, mechanical properties of spinal materials, friction coefficients at the interfaces and geometry of spinal segments would affect the relative micromotion and spinal stability. A finite clement model of the human lumbar spine segments (L4-L5) was constructed to investigate the mechanical sensitivity at the interfaces between bone and cage. Relative micromotion. Posterior axial displacement. bone stress, cage stress and friction force were predicted in changes of friction coefficients, loading conditions. bone density and age-related material/geometric properties of the spinal segments. Relative micromotion (slip distance in a static loading means relative micromotion in routine activity) at the interfaces increased significantly as the mechanical properties of cancellous bone, annulus fibers or/and ligaments decrease or/and as the friction coefficient at the interfaces decreases. The contact normal force at the interfaces decreased as cancellous bone density decreases or/and as the friction coefficient increases A significant increase of slip distance at anterior annulus occurred with an addition of torsion to compressive preload. Relative micromotion decreased with an increase of disc area. In conclusion. relative micromotion, stress response. Posterior axial displacement and contact normal force are sensitive to the friction coefficient of the interfaces, bone density, loading conditions and age-related geometric/material changes.

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Development of Imaging Gamma Probe Using the Position Sensitive PMTube (위치 민감형 광전자증배관을 이용한 영상용 감마프로브의 개발)

  • Bong, Jeong-Gyun;Kim, Hui-Jung;So, Su-Gil;Kim, Han-Myeong;Lee, Jong-Du;Gwon, Su-Il
    • Journal of Biomedical Engineering Research
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    • v.20 no.1
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    • pp.107-113
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    • 1999
  • The purpose of this study was to develop a miniature imaging gamma probe with high performance that can detect small or residual tumors after surgery. Gamma probe detector system consists of NaI(Tl) scintillator, position sensitive photomultiplier tube (PSPMT), and collimator. PSPMT was optically coupled with 6.5 mm thick, 7.62 cm diameter of NaI(Tl) crystal and supplied with -1000V for high voltage. Parallel hexagonal hole collimator was manufactured for characteristics of 40-mm hole length, 1.3-mm hole diameter, and 0.22 mm septal thickness. Electronics consist of position and trigger signal readout systems. Position signals were obtained with summing, subtracting, and dividing circuit using preamplifer and amplifier. Trigger signals were obtained using summing amplifier, constant fraction discriminator, and gate and delay generator module with preamplifer. Data acquisition and processing were performed by Gamma-PF interface board inserted into pentium PC and PIP software. For imaging studies, flood and slit mask images were acquired using a point source. Two hole phantom images were also acquired with collimator. Intrinsic and system spatial resolutions were measured as 3.97 mm and 5.97 mm, respectively. In conclusion, Miniature gamma probe images based on the PSPMT showed good image quality, we conclude that the miniature imaging gamma probe was successfully developed and good image data were obtained. However, further studies will be required to optimize imaging characteristics.

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Study on low-level laser therapy device according to the obesity development (비만치료기 개발에 따른 저준위레이저에 관한 연구)

  • Lee, Sang-sik;Kim, Jun-tae;Jeong, Jin-hyoung;Kim, Nam-Sun
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.9 no.1
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    • pp.82-89
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    • 2016
  • And by entering into an aging society with economic growth "beautiful and healthy desire to live', aesthetics industry as promote interest in 'Anti-aging' is emerging as a promising business increased significantly the skin care market. However, the management of the hospital or the temporal order to receive professional care providers, spatial, and cost constraints caused many companies to solve this problem began to approach the Home Care Area. Global trends in personal skin care market has been activated, the domestic has been activated at low cost, private market due to the recession. We have performed this test in order to develop a skin care device for home in order to compensate for this point.In this paper, we develop a low-level laser to create a personal skin care products and sought to incorporate them into the skin cosmetic.Expand the pores by using the low-level laser to the skin by to the dermal layer of the skin was penetrated aim experiment the ampoule, and by a comparison of the medical low-level laser reliability and determine the effectiveness or absence of the performance and efforts to commercialize.