• Title/Summary/Keyword: wave control

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Hacking attack and vulnerabilities in vehicle and smart key RF communication (차량과 스마트키 RF통신에 대한 해킹 공격 및 취약점에 대한 연구)

  • Kim, Seung-woo;Park, Dea-woo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.24 no.8
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    • pp.1052-1057
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    • 2020
  • With the development of new ICT technology, smart keys for vehicles are terminals with ICT technology. Therefore, when the vehicle and the smart key communicate with RF, a cyber hacking attack is possible. Cyber-attacks on smart keys can pose a threat to vehicle theft and vehicle control. Therefore, it is necessary to study hacking attacks and vulnerabilities of smart keys for autonomous vehicles. In this paper, we analyze the cyber attack case of RF communication for vehicles and smart keys. In addition, a real RF cyber attack on the smart key is performed, and the vulnerability of radio wave replication in the same frequency band is found. In this paper, we analyze the vulnerability of RF communication between vehicles and smart keys, and propose a countermeasure against cyber security. In the future, plans to strengthen cyber attacks and security through the popularization of autonomous vehicles will become basic data to protect human and vehicle safety.

Seven Days Breaking Up Prolonged Sitting Improves Systemic Endothelial Function in Sedentary Men (일주일간의 간헐적 좌식차단의 혈관기능 개선 효과)

  • Park, Soo Hyun;Yoon, Eun Sun;Jae, Sae Young
    • Exercise Science
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    • v.26 no.1
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    • pp.61-68
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    • 2017
  • PURPOSE: To examine the cumulative (7 days) effect of breaking up prolonged sitting on systemic endothelial function in sedentary men. METHODS: Thirty sedentary men ($33.93{\pm}5.72years$) participated in two randomized 7 days sitting trial (Sit group (control) vs. Breaks group). The protocol of Breaks group is as follows: 4-minute of moderate-intensity marching in place (walking) every 1 hour during business hour (total: 8 breaks/day). Assessment of brachial artery endothelial function using flow-mediated dilation (FMD) and arterial stiffness indices (augmentation index, arterial pressure and pulse wave velocity) were measured before and after 7 days treatment. RESULTS: Brachial artery FMD significantly increased after 7 days breaking up prolonged sitting treatment (Breaks groups, $9.65{\pm}2.61$ to $9.62{\pm}2.6%$) compared with 7 days prolonged sitting (Sit group, $8.37{\pm}3.41$ to $10.11{\pm}3.75%$) (interaction effect, p=.004). Arterial pressure (AP) significantly increased after treatment (Breaks group, $2.75{\pm}2.19$ to $2.38{\pm}1.63mmHg$, p=.002) in Sit group but there was no change (Sit group, $1.00{\pm}3.18$ to $2.50{\pm}9.23mmHg$) in Breaks groups (interaction effect, p=.008). CONCLUSIONS: These finding show that 7 days regular breaking up prolonged sitting improve in FMD, compared with prolonged sitting. Therefore, regular breaking up prolonged sitting may improve systemic endothelial function in sedentary men.

Exploration of shockwaves on polymeric membrane physical properties and performance

  • Lakshmi, D. Shanthana;Saxena, Mayank;Ekambaram, Shivakarthik;Sivaraman, Bhalamurugan
    • Membrane and Water Treatment
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    • v.12 no.1
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    • pp.43-49
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    • 2021
  • The Commercial polymeric membranes like Polysulfone (PSF), Polyvinylidene difluoride (PVDF) and Polyacrylonitrile (PAN) which are an integral part of water purification investigation were chosen for the shockwave (SW) exposure experiment. These membranes were prepared by blending polymer (wt. %) / DMF (solvent) followed by phase-inversion casting technique. Shockwaves are generated by using Reddy Tube lab module (Table-top Shocktube) with range of pressure (1.5, 2.5 and 5 bar). Understanding the changes in membrane before and after shock wave treatment by parameters, i.e., pure water flux (PWF), rejection (%), porosity, surface roughness (AFM), morphology (SEM) and contact angle which can significantly affect the membrane's performance. Flux values PSf membranes shows increase, 465 (pristine) to 524 (1.5wt%) LMH at 50 Psi pressure and similar enhancement was observed at 100Psi (625 to 696 LMH). Porosity also shows improvement from 73.6% to 76.84% for 15wt% PSf membranes. It was observed that membranes made of polymers such as PAN and PSF (of high w/w %) exhibits some resistance against shockwaves impact and are stable compared to other membranes. Shockwave pressure of up to 1.5 bar was sufficient enough to change properties which are crucial for performance. Membranes exposed to a maximum pressure of 5 bar completely scratched the surface and with minimum pressure of 1.5bar is optimum enough to improve the water flux and other parameters. Initial results proved that SW may be suitable alternative route to minimize/control membrane fouling and improve efficiency.

Design of a Free-form Mueller Matrix Ellipsometer with Imperfect Compensators (불완전한 보정기를 적용한 자유형 뮬러행렬타원계의 설계)

  • Kim, Sang Youl
    • Korean Journal of Optics and Photonics
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    • v.33 no.2
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    • pp.59-66
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    • 2022
  • A free-form Mueller matrix ellipsometer (MME) based on independent control of the azimuthal angle of each polarizing element is introduced. The azimuthal angles of the polarizer and the matching compensator which generate the optimum Stokes vectors of an incident beam are investigated for the polarization state generator, where the spectral responses of the retardation angle and transmittance ratio of a nonideal compensator are taken into account. Similarly, the azimuthal angles of the analyzer and the corresponding compensator are investigated for the polarization-state detector, to unambiguously determine the Stokes vector of the outcoming beam from the sample, and explicit expressions for the Stokes elements are derived. Since the suggested technique enables one to utilize a nonideal quarter-wave plate as the compensator for an MME, it will contribute to the construction and application of a Mueller matrix spectroscopic ellipsometer (MMSE) operating over a wide spectral range from deep ultra-violet to near infrared.

Evaluation of the Public Health Emergency Response to the COVID-19 Pandemic in Daegu, Korea During the First Half of 2020

  • Lee, Hwajin;Kim, Keon-Yeop;Kim, Jong-Yeon;Kam, Sin;Lee, Kyeong Soo;Lee, Jung Jeung;Hong, Nam Soo;Hwang, Tae-Yoon
    • Journal of Preventive Medicine and Public Health
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    • v.55 no.4
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    • pp.360-370
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    • 2022
  • Objectives: This study evaluated the response in Daegu, Korea to the first wave of the coronavirus disease 2019 (COVID-19) pandemic according to a public health emergency response model. Methods: After an examination of the official data reported by the city of Daegu and the Korea Centers for Disease Control and Prevention, as well as a literature review and advisory meetings, we chose a response model. Daegu's responses were organized into 4 phases and evaluated by applying the response model. Results: In phase 1, efforts were made to block further transmission of the virus through preemptive testing of a religious group. In phase 2, efforts were concentrated on responding to mass infections in high-risk facilities. Phase 3 involved a transition from a high-intensity social distancing campaign to a citizen participation-based quarantine system. The evaluation using the response model revealed insufficient systematic preparation for a medical surge. In addition, an incorporated health-related management system and protection measures for responders were absent. Nevertheless, the city encouraged the participation of private hospitals and developed a severity classification system. Citizens also played active roles in the pandemic response by practicing social distancing. Conclusions: This study employed the response model to evaluate the early response in Daegu to the COVID-19 pandemic and revealed areas in need of improvement or maintenance. Based on the study results, creation of a systematic model is necessary to prepare for and respond to future public health emergencies like the COVID-19 pandemic.

Design of a Multilayer Radar Absorbing Structure Based on Particle Swarm Optimization Algorithm (입자 군집 최적화(PSO) 알고리즘 기반 다층 레이더 흡수 구조체 설계)

  • Choi, Young-Doo;Han, Min-Seok
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.15 no.5
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    • pp.367-379
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    • 2022
  • In this paper, a multilayer radar absorbing structure was designed using the Particle Swarm Optimization (PSO) algorithm, and the characteristics of the multilayer radar absorbing structure were analyzed. It was shown that design values can be derived quickly and accurately by applying PSO to the design of a multilayer radar absorbing structure, and it is also shown that the optimal multilayer radar absorbing structure can be designed especially for an oblique incident. In addition, it was shown that the optimal value that meets the performance requirements can be determined even in a combination of various design parameters. It is presented through a comprehensive flowchart including the equations and detailed descriptions of all variables for each step. From the results of this paper, it is possible to omit complex and many calculations for designing a multilayer radar absorbing structure, and it is possible to use various composite materials. It can be utilized in the design and development of multilayer radar absorbing structures.

Effect of Functional Exercise Using Linear Ladder on EEG Activities in College Men (줄사다리를 이용한 기능적 운동이 남자대학생의 뇌파 활성에 미치는 영향)

  • Jung, Suk Yool;Lee, Hae Lim;Lee, Sung Ki
    • Journal of Naturopathy
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    • v.11 no.2
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    • pp.79-84
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    • 2022
  • Background: Exercise influences the generation of brain cells through learning and experience in the process of acquiring motor skills and helps improve brain function. It is necessary to scientifically verify how brain wave activity, a method of analyzing brain function, affects movement. Purposes: We scientifically identify the positive effects on EEG activity when applying complex functional linear ladder movements in an appropriate environment. Methods: After recruiting 30 male university students, we divided them into a linear ladder exercise group, a treadmill exercise group, and a control group, and exercise was applied and measured repeatedly for ten weeks. Results: There was a statistically significant change between groups in the left prefrontal lobe of alpha waves when exercise was applied (p < .05). Conclusions: Although exercise has a positive effect on EEG, line ladder exercise, which applies a complex pattern and produces more leg movement, appears to have a better impact on brain function than traditional aerobic exercise.

Smart Helmet for Vital Sign-Based Heatstroke Detection Using Support Vector Machine (SVM 이용한 다중 생체신호기반 온열질환 감지 스마트 안전모 개발)

  • Jaemin, Jang;Kang-Ho, Lee;Subin, Joo;Ohwon, Kwon;Hak, Yi;Dongkyu, Lee
    • Journal of Sensor Science and Technology
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    • v.31 no.6
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    • pp.433-440
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    • 2022
  • Recently, owing to global warming, average summer temperatures are increasing and the number of hot days is increasing is increasing, which leads to an increase in heat stroke. In particular, outdoor workers directly exposed to the heat are at higher risk of heat stroke; therefore, preventing heat-related illnesses and managing safety have become important. Although various wearable devices have been developed to prevent heat stroke for outdoor workers, applying various sensors to the safety helmets that workers must wear is an excellent alternative. In this study, we developed a smart helmet that measures various vital signs of the wearer such as body temperature, heart rate, and sweat rate; external environmental signals such as temperature and humidity; and movement signals of the wearer such as roll and pitch angles. The smart helmet can acquire the various data by connecting with a smartphone application. Environmental data can check the status of heat wave advisory, and the individual vital signs can monitor the health of workers. In addition, we developed an algorithm that classifies the risk of heat-related illness as normal and abnormal by inputting a set of vital signs of the wearer using a support vector machine technique, which is a machine learning technique that allows for rapid binary classification with high reliability. Furthermore, the classified results suggest that the safety manager can supervise the prevention of heat stroke by receiving feedback from the control system.

Effects of an Aromatherapy Education Program on Stress, Self-efficacy, and Autonomic Nervous System Function of Female College Students Preparing for Employment (아로마테라피 교육 프로그램이 취업준비 여대생의 스트레스와 자기효능감 및 자율신경계에 미치는 영향)

  • Eun-Joo Lee;Eun-Jin Lim
    • Journal of The Korean Society of Integrative Medicine
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    • v.11 no.3
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    • pp.11-23
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    • 2023
  • Purpose : The stress of job-seeking college students is gradually worsening due to the continuing recession in the job market. Therefore, this study aims to verify whether intervention with an 'aromatherapy education program,' which combines theory and practice, has greater effect on stress, self-efficacy, and autonomic nervous system function than simple inhalation of essential oils in female college students preparing for employment. Methods : A single-blind, randomized controlled trial was conducted once a week for a total of 4 weeks with 29 female college students preparing for employment. Interventions included essential oil inhalation combined with an aromatherapy education program (experimental group(EG), n=14) and essential oil inhalation alone (control group(CG), n=15); measurements were taken before, immediately after, and 2 weeks after completion of the intervention. Evaluations were conducted using the job-seeking stress scale, stress VAS, self-efficacy scale, and a pulse-wave measuring instrument. Results : There were significant differences between the CG and EG groups with repeated measurements of job-seeking stress (p=.003), cognitive stress (p<.001), and self-efficacy (p<.001). There was a significant interaction between group and time. There were also significant differences between the CG and EG in terms of autonomic nervous system changes stress index(p=.047), total power(p=.029), high frequency(p=.036), and low frequency/high frequency ratio(p=.049). However, there was no significant difference in low frequency between the groups. Conclusion : The aromatherapy education program was more effective in improving job-seeking stress, cognitive stress, self-efficacy, and autonomic nervous system function than simple essential oil inhalation. For the aromatherapy education program to be useful as a complementary intervention for stress management in job seekers, it will be necessary to gather additional evidence of its efficacy by conducting follow-up studies with diverse participants and expanding the numbers, and durations, of the interventions.

The Effect of Using Zentangle Art Therapy on Improving the Attention Span of People with Developmental Disabilities in Lifelong Education Center (젠탱글 활용 미술치료가 평생교육센터 이용 발달장애인의 주의집중력에 미치는 효과)

  • Kong, Maria;Kwak, Bong-Cheol;Kim, Joon-Soo;Jeong, Yeo-Jin
    • Journal of Korea Entertainment Industry Association
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    • v.13 no.4
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    • pp.419-429
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    • 2019
  • The objective of this study was to look into the effect of using Zentangle art therapy on improving the attention span of people with developmental disabilities in Lifelong Education Center. The 29 people with developmental disabilities in Lifelong Education Center of D-University in K-city were the subjects to reach the primary goal of this study. Nine of the subjects were assigned to the experimental group of the Zentangle art therapy, ten to the control group. As for the study tools, 3.5x3.5 inch paper card, various colors of Deco Markers, and Zentangle cards for the experimental group. The FAIR and MindWaveMobile (MWM) were used to measure the effectiveness. The twelve 30-minute sessions of the program, held from October to December in 2018, has shown the result that the attention span improved on the experimental group using the Zentangle art therapy.