• Title/Summary/Keyword: Data Communication-Less

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Multiple-image Encryption and Multiplexing Using a Modified Gerchberg-Saxton Algorithm in Fresnel-transform Domain and Computational Ghost Imaging

  • Peiming Zhang;Yahui Su;Yiqiang Zhang;Leihong Zhang;Runchu Xu;Kaimin Wang;Dawei Zhang
    • Current Optics and Photonics
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    • v.7 no.4
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    • pp.362-377
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    • 2023
  • Optical information processing technology is characterized by high speed and parallelism, and the light features short wavelength and large information capacity; At the same time, it has various attributes including amplitude, phase, wavelength and polarization, and is a carrier of multi-dimensional information. Therefore, optical encryption is of great significance in the field of information security transmission, and is widely used in the field of image encryption. For multi-image encryption, this paper proposes a multi-image encryption algorithm based on a modified Gerchberg-Saxton algorithm (MGSA) in the Fresnel-transform domain and computational ghost imaging. First, MGSA is used to realize "one code, one key"; Second, phase function superposition and normalization are used to reduce the amount of ciphertext transmission; Finally, computational ghost imaging is used to improve the security of the whole encryption system. This method can encrypt multiple images simultaneously with high efficiency, simple calculation, safety and reliability, and less data transmission. The encryption effect of the method is evaluated by using correlation coefficient and structural similarity, and the effectiveness and security of the method are verified by simulation experiments.

The Effect of the Use of Smart Devices by the Elderly on Life Satisfaction : Focusing on the Mediating Effects of Self-esteem (노인의 스마트기기 활용이 삶의 만족도에 미치는 영향 : 자아존중감의 매개효과를 중심으로)

  • Kim, Ja-Young
    • The Journal of the Korea Contents Association
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    • v.22 no.5
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    • pp.424-434
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    • 2022
  • This study is to verify the mediating effect of self-esteem on the effect of the elderly's smart device use on life satisfaction. To this end, secondary data analysis was conducted using the Korea Media Panel Survey conducted by the Information and Communication Policy Institute in 2021. The responses of 3,211 people in their 60s or older who are the subjects of this study were utilized. For analysis, descriptive statistics, correlation, and multiple regression analysis were performed using SPSS, and the Sobel test was conducted to verify mediating effects. As a result, smart device utilization averaged 2.13 points out of 5, indicating that the actual utilization level was less than half. The use of smart devices, an independent variable, had a positive effect on the dependent variable, life satisfaction. Self-esteem, which is a parameter, has been verified as a partial mediating effect in that smart device use affects life satisfaction. Based on the results of this study, various policy and practical measures were proposed to increase the smart device utilization rate of the elderly in Korea, improve self-esteem and life satisfaction, so that they can spend a happy old age.

Enhancing Communication on Medication Side Effects: Insights from a Survey Study (의약품 부작용 정보 전달의 중요성: 설문조사 기반 고찰)

  • Ji Hye Choi;Hye Seong Han;Mi Kyong Shim;Hyun Soon Sohn
    • Korean Journal of Clinical Pharmacy
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    • v.34 no.2
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    • pp.126-133
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    • 2024
  • Background: Medication's benefits and harms require careful management. Laws mandate pharmacists to provide essential medication details since inadequate counseling may pose risks. This study explores public expectations for pharmacist-provided side effect information to enhance safety. Methods: A self-developed questionnaire was created for participant to self-report, refined through pilot surveys with experts and laypersons. Nineteen items were categorized into four sections, using closed-ended questions. Adults over 20, having obtained prescription medications within the past year, were surveyed via convenience sampling. Data analysis employed descriptive statistics and T-tests using IBM SPSS Statistics 21 and Microsoft Excel. Results: The study involved 189 participants, with a slightly higher proportion of females (59.3%) than males (40.7%), predominantly in their 20s (45.0%) and college graduates (57.1%). Health professionals represented 76.2% of respondents. Over half visited pharmacies at least 5 times yearly for prescriptions. Indirect experience with side effects was more common (30.2%) than direct experience (17.5%). Most (82.0%) showed interest in media-reported side effect events. Satisfaction with pharmacist-provided side effect explanations was low (59.7%), but importance was high (98.9%). Preferences favored combined verbal and written explanations (65.1%), with a majority desiring explanations for common but less serious side effects (82.5%). Healthcare professionals found explanations significantly more sufficient than non-professionals did. Older individuals, those living with elderly, and frequent pharmacy visitors attributed greater importance to pharmacist-provided explanations. Conclusion: Koreans view pharmacist-provided medication side effect explanations as vital but find current services lacking. Enhancements in content and delivery methods are needed in pharmacy counseling to meet public expectations.

Design of V-Band Waveguide Slot Sub-Array Antenna for Wireless Communication Back-haul (무선통신 백-홀용 V-밴드 도파관 슬롯 서브-배열 안테나의 설계)

  • Noh, Kwang-Hyun;Kang, Young-Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.7
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    • pp.334-341
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    • 2016
  • In this paper, the study of a waveguide aperture-coupled feed-structured antenna has been conducted for the purpose of applying it to a wireless back-haul system sufficient for high-capacity gigabits-per-second data rates. For this study, a $32{\times}32$ waveguide slot sub-array antenna with a corporate-feed structure was designed and produced. Also, this antenna is used at 57 GHz to 66 GHz in the V-band. The construction of the antenna is a laminated form with radiating parts (outer groove and slot, cavity), a coupled aperture, and feeds in each. The antenna was designed with HFSS, which is based on 3D-FEM, produced with aluminum processed by a precision-controlled milling machine, and assembled after a silver-plating process. The measurement result from analysis of the characteristics of the antenna shows that return loss is less than -12 dB, VSWR < 2.0, and a wide bandwidth ranges up to 16%. An overall first side lobe level is less than -12.3 dB, and a 3 dB beam width is narrow at about $1.85^{\circ}$. Also, antenna gain is 38.5 dBi, offering high efficiency exceeding 90%.

Knowledge and Attitude Towards Tobacco Smoking among 13-15 Year-Old School Children in Viet Nam - Findings from GYTS 2014

  • Nguyen, Thanh Huong;Nguyen, Trung Kien;Kim, Bao Giang;Hoang, Van Minh;Phan, Thi Hai;Doan, Thu Huyen;Luong, Ngoc Khue;Nguyen, Thuy Linh;Nguyen, Tuan Lam;Pham, Thi Quynh Nga
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.sup1
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    • pp.37-42
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    • 2016
  • Studies have shown that smoking is a learnt behavior, often initiated during adolescence. This paper aims to describe tobacco-related knowledge, attitude and associations among school adolescents aged 13-15 with exposure to anti-smoking information. Using data from the Global Youth Tobacco Survey (GYTS) in Viet Nam, 2014, knowledge was measured through 4 questions about tobacco use, and attitude was assessed through 3 questions on personal, social and environmental aspects. Students giving most anti-tobacco responses to all questions were considered as having correct knowledge or appropriate attitude or both. Access to anti-smoking information was determined by exposure to any media messages on tobacco control during the past 30 days and teaching in school about the danger of tobacco use during the past 12 months. A substantial percentage of students thought that being near others who smoke might be harmful to them and smoking is harmful to health (89.4% and 89.6% respectively). However, only 46.4% reported that it is definitely difficult to quit smoking and 66.9% thought that smoking for only 1 or 2 years, once stopped, is harmful to health. Slightly more than half of the respondents reported appropriate attitude that young smokers have fewer friends than others and smoking makes them less attractive and less comfortable at social events. Noticing anti-smoking messages in the media together with having lessons in school about the dangers of tobacco substantially increased the likelihood of having correct knowledge, appropriate attitude and both. Despite relatively high awareness about smoking harms, effective educational communication is still highly needed to improve the level of comprehensive knowledge and an appropriate attitude regarding tobacco use.

Informative Role of Marketing Activity in Financial Market: Evidence from Analysts' Forecast Dispersion

  • Oh, Yun Kyung
    • Asia Marketing Journal
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    • v.15 no.3
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    • pp.53-77
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    • 2013
  • As advertising and promotions are categorized as operating expenses, managers tend to reduce marketing budget to improve their short term profitability. Gauging the value and accountability of marketing spending is therefore considered as a major research priority in marketing. To respond this call, recent studies have documented that financial market reacts positively to a firm's marketing activity or marketing related outcomes such as brand equity and customer satisfaction. However, prior studies focus on the relation of marketing variable and financial market variables. This study suggests a channel about how marketing activity increases firm valuation. Specifically, we propose that a firm's marketing activity increases the level of the firm's product market information and thereby the dispersion in financial analysts' earnings forecasts decreases. With less uncertainty about the firm's future prospect, the firm's managers and shareholders have less information asymmetry, which reduces the firm's cost of capital and thereby increases the valuation of the firm. To our knowledge, this is the first paper to examine how informational benefits can mediate the effect of marketing activity on firm value. To test whether marketing activity contributes to increase in firm value by mitigating information asymmetry, this study employs a longitudinal data which contains 12,824 firm-year observations with 2,337 distinct firms from 1981 to 2006. Firm value is measured by Tobin's Q and one-year-ahead buy-and-hold abnormal return (BHAR). Following prior literature, dispersion in analysts' earnings forecasts is used as a proxy for the information gap between management and shareholders. For model specification, to identify mediating effect, the three-step regression approach is adopted. All models are estimated using Markov chain Monte Carlo (MCMC) methods to test the statistical significance of the mediating effect. The analysis shows that marketing intensity has a significant negative relationship with dispersion in analysts' earnings forecasts. After including the mediator variable about analyst dispersion, the effect of marketing intensity on firm value drops from 1.199 (p < .01) to 1.130 (p < .01) in Tobin's Q model and the same effect drops from .192 (p < .01) to .188 (p < .01) in BHAR model. The results suggest that analysts' forecast dispersion partially accounts for the positive effect of marketing on firm valuation. Additionally, the same analysis was conducted with an alternative dependent variable (forecast accuracy) and a marketing metric (advertising intensity). The analysis supports the robustness of the main results. In sum, the results provide empirical evidence that marketing activity can increase shareholder value by mitigating problem of information asymmetry in the capital market. The findings have important implications for managers. First, managers should be cognizant of the role of marketing activity in providing information to the financial market as well as to the consumer market. Thus, managers should take into account investors' reaction when they design marketing communication messages for reducing the cost of capital. Second, this study shows a channel on how marketing creates shareholder value and highlights the accountability of marketing. In addition to the direct impact of marketing on firm value, an indirect channel by reducing information asymmetry should be considered. Potentially, marketing managers can justify their spending from the perspective of increasing long-term shareholder value.

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Measurement Delay Error Compensation for GPS/INS Integrated System (GPS/INS 통합시스템의 측정치 시간지연오차 보상)

  • Lyou Joon;Lim You-Chol
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.41 no.1
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    • pp.1-8
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    • 2004
  • The INS(Inertial Navigation System) provides high rate position, velocity and attitude data with good short-term stability while the GPS(Global Position System) provides position and velocity data with long-term stability. By integrating the INS with GPS, a navigation system can be achieved to Provide highly accurate navigation Performance. For the best performance, time synchronization of GPS and INS data is very important in GPS/INS integrated system But, it is impossible to synchronize them exactly due to the communication and computation time-delay. In this paper, to reduce the error caused by the measurement time-delay in GPS/INS integrated systems, error compensation methods using separate bias Kalman filter are suggested for both the loosely-coupled and the tightly-coupled GPS/INS integration systems. Linearized error models for the position and velocity matching GPS/INS integrated systems are Int derived by linearizing with respect to its time-delay and augmenting the delay-state into the conventional state equations for each case. And then separate bias Kalman Inter is introduced to estimate the time-delay during only initial navigation stage. The simulation results show that the present method is effective enough resulting in considerably less position error.

Peer-to-Peer Transfer Scheme for Multimedia Partial Stream using Client Initiated with Prefetching (멀티미디어 데이터를 위한 피어-투-피어 전송모델)

  • 신광식;윤완오;정진하;최상방
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.7B
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    • pp.598-612
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    • 2004
  • Client requests have increased with the improvement of network resources at client side, whereas network resources at server side could not keep pace with the increased client request. Therefore, it is primary factor of the Qos that efficiently utilize network resources at server side. In this paper, we proposed a new model that peer-to-peer transfer scheme for partial multimedia stream based on CIWP which it decrease server network bandwidth by utilizing client disk resources saves additional server network resources. Especially, adapting Threshold_Based Multicast scheme guarantees to do that data transfer within clients never exceed service time of previous peer by restriction of which data size transferring from previous peer less than data size transferring from server. Peer-to-peer transfer within clients is limited in same group classified as ISPs. Our analytical result shows that proposed scheme reduces appling network resources at server side as utilizing additional client disk resource. furthermore, we perform various simulation study demonstrating the performance gain through comparing delay time and proportion of waiting requesters. As a result, when we compared to Threshold_Based Multicast scheme, the proposed scheme reduces server network bandwidth by 35%.

Low-power 6LoWPAN Protocol Design (저 전력 6LoWPAN 프로토콜 설계)

  • Kim, Chang-Hoon;Kim, Il-Hyu;Cha, Jung-Woo;Nam, In-Gil;Lee, Chae-Wook
    • Journal of the Institute of Convergence Signal Processing
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    • v.12 no.4
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    • pp.274-280
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    • 2011
  • Due to their rapid growth and new paradigm applications, wireless sensor networks(WSNs) are morphing into low power personal area networks(LoWPANs), which are envisioned to grow radically. The fragmentation and reassembly of IP data packet is one of the most important function in the 6LoWPAN based communication between Internet and wireless sensor network. However, since the 6LoWPAN data unit size is 102 byte for IPv6 MTU size is 1200 byte, it increases the number of fragmentation and reassembly. In order to reduce the number of fragmentation and reassembly, this paper presents a new scheme that can be applicable to 6LoWPAN. When a fragmented packet header is constructed, we can have more space for data. This is because we use 8-bits routing table ill instead of 16-bits or 54-bits MAC address to decide the destination node. Analysis shows that our design has roughly 7% or 22% less transmission number of fragmented packets, depending on MAC address size(16-bits or 54-bits), compared with the previously proposed scheme in RFC4944. The reduced fragmented packet transmission means a low power consumption since the packet transmission is the very high power function in wireless sensor networks. Therefore the presented fragmented transmission scheme is well suited for low-power wireless sensor networks.

Doctor's and Nurses' Perception and Experiences of DNR (DNR(Do-Not-Resuscitate)에 대한 의사와 간호사의 경험 및 인지도)

  • Han, Sung-Suk
    • Journal of Korean Academy of Nursing Administration
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    • v.11 no.3
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    • pp.255-264
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    • 2005
  • This study is a descriptive research in investigating the perception of doctors and nurses with regard to DNR, and data were collected through survey questionnaires. The period of collecting data was between July 15 and October 30, 2004, distributing 128 questionnaires to 128 participants, and a total of 110 questionnaires from 55 doctors and 55 nurses were collected (86%)among 70 different hospitals. The collected data were analyzed using SAS program to get real number and percentage, and were also analyzed with $X^2$-test. The Study Results are as follows: 1. Respondents who agreed with the necessity of DNR was 97.27%, the reasons of DNR necessity were 59.20% of 'impossibility of recovery in spite of lots of efforts,' and 35.20% of 'for the purpose of choosing a comfortable and dignified death,' and 97.2% of respondents answered that it was necessary to give explanation of DNR to serious case patients, terminal patients and their family. 2. Problems derived from DNR decisions were 44.44% of 'lack of treatment and nursing,' 21.11% of 'guilty conscience about failing to do best efforts,' and 71.57% of CPR implementation right after DNR decision. 3. Reasons of implementing CRP for patients with DNR decision were 50.94% of 'for the presence of family and relatives at the point of patient's death,' 20.76% of 'guardian's change of DNR decision,' and 16.98% of 'no communication for the consent after DNR decision.' 4. With regard to who was to make DNR decision? there was a difference in the opinion between doctors' and nurses' group while the group of doctors chose 'by the consent of the family and the doctor in charge,' and the group of nurses chose 'patient's intension,' and with regard to Have you received DNR related education? and Will people who want DNR increase if there is explanation given? there was a difference between the two groups. 5. In the catholic institutions, respondents of 71.7% said that it was necessary to take DNR depending upon the situation, and 73% said that they had performed DNR before. 6. In the institutions with over 500 beds, 91.92% of respondents said that there should be an establishment of guideline book as a written format to implement DNR. From the results of this study, it was found that DNR was implemented and executed broadly in clinical fields in the absence of necessary instructions and/or guideline, and that DNR order was placed to the group of doctors who got less opportunity for proper education than did that of nurses.

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