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Factors influencing the recognition of clinical nurses' code of ethics; Focusing on consciousness of biomedical ethics, moral sensitivity, and critical thinking deposition (임상간호사의 간호사 윤리강령 인식의 영향 요인; 생명의료 윤리의식, 도덕적 민감성, 비판적사고 성향을 중심으로)

  • Choi, Young-sil;Kim, Sang-Suk
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.12
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    • pp.660-671
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    • 2020
  • This study is a descriptive survey study that attempted to confirm clinical nurses' consciousness of biomedical ethics, moral sensitivity, critical thinking deposition, and nursing ethics code of clinical nurses, as well as to identify the factors influencing the recognition of the nursing code of ethics. The general and ethical characteristics of the subject were calculated by frequency, percentage, mean, and standard deviation, and the difference for each variable according to the general and ethical characteristics was analyzed using SAS 9.4, independent t-test, and one-way ANOVA, and Scheffé test. The average, standard deviation, and the minimum and maximum values were used for the scores of each variable, and the correlation was determined using the Pearson correlation coefficient. Multiple regression was used to identify the factors that influence the recognition of the nurse's code of ethics. All variables showed significant correlations. Critical thinking deposition (p<.05) was the most influential variable in recognizing the code of ethics for nurses. Critical thinking deposition (p<.001), consciousness in biomedical ethics (p<.001), and moral sensitivity (p<.001) were shown to be affected in order, with 27.4% explaining power. Therefore, it is necessary to develop and apply educational programs to clinical nurses that can improve critical thinking, life and bioethics, and moral sensitivity.

Effect on the Flow and Heat Transfer of Endwall by Installation of Cut Pin in Front of Pin-fin Array of Turbine Blade Cooling Passage (가스터빈 블레이드 핀-휜 내부 냉각 유로에 분절핀 설치에 따른 바닥면 유동 및 열전달 특성)

  • Choi, Seok Min;Kim, Su Won;Park, Hee Seung;Kim, Yong Jin;Cho, Hyung Hee
    • Journal of the Korean Society of Propulsion Engineers
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    • v.24 no.5
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    • pp.43-55
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    • 2020
  • The effect of cutted pin in front of pin-fin array was analyzed for increasing the cooling performance of gas turbine blade. The numerical simulations were conducted to figure out the flow and thermal characteristics. The base case which is staggered pin-fin array, cut pin case 1 which has X2/Dp=1.25 cut pin and cut pin case 2 which has X3/Dp=1.75 cut pin were compared. The results showed that cut pin increases the strength of the horseshoe vortex which occurred at the leading edge of pin-fin array. Furthermore, the wake effect is reduced at the trailing edge of pin-fin array. As a result, the heat transfer distribution on the endwall increases. However, the friction factor increases owing to the installation of cut pin, but the thermal performance factor is increased maximum 23.8% in cut pin case 2. Therefore, installation of cut pin will be helpful for increasing the cooling performance of pin-fin array of gas turbine blade.

Analysis of Intrinsic Patterns of Time Series Based on Chaos Theory: Focusing on Roulette and KOSPI200 Index Future (카오스 이론 기반 시계열의 내재적 패턴분석: 룰렛과 KOSPI200 지수선물 데이터 대상)

  • Lee, HeeChul;Kim, HongGon;Kim, Hee-Woong
    • Knowledge Management Research
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    • v.22 no.4
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    • pp.119-133
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    • 2021
  • As a large amount of data is produced in each industry, a number of time series pattern prediction studies are being conducted to make quick business decisions. However, there is a limit to predicting specific patterns in nonlinear time series data due to the uncertainty inherent in the data, and there are difficulties in making strategic decisions in corporate management. In addition, in recent decades, various studies have been conducted on data such as demand/supply and financial markets that are suitable for industrial purposes to predict time series data of irregular random walk models, but predict specific rules and achieve sustainable corporate objectives There are difficulties. In this study, the prediction results were compared and analyzed using the Chaos analysis method for roulette data and financial market data, and meaningful results were derived. And, this study confirmed that chaos analysis is useful for finding a new method in analyzing time series data. By comparing and analyzing the characteristics of roulette games with the time series of Korean stock index future, it was derived that predictive power can be improved if the trend is confirmed, and it is meaningful in determining whether nonlinear time series data with high uncertainty have a specific pattern.

Mobile Robot for Indoor Air Quality Monitoring (이동형 실내 공기질 측정 로봇)

  • Lee, So-Hwa;Koh, Dong-Jin;Kim, Na-Bin;Park, Eun-Seo;Jeon, Dong-Ryeol;Bong, Jae Hwan
    • The Journal of the Korea institute of electronic communication sciences
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    • v.17 no.3
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    • pp.537-542
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    • 2022
  • There is a limit to the current indoor air quality (IAQ) monitoring method using fixed sensors and devices. A mobile robot for IAQ monitoring was developed by mounting IAQ monitoring sensors on a small multi-legged robot to minimize vibration and protect the sensors from vibration while robot moves. The developed mobile robot used a simple gait mechanism to enable the robot to move forward, backward, and turns only with the combination of forward and reverse rotation of the two DC motors. Due to the simple gait mechanism, not only IAQ data measurements but also gait motion control were processed using a single Arduino board. Because the mobile robot has small number of electronic components and low power consumption, a relatively low-capacity battery was mounted on the robot to reduce the weight of the battery. The weight of mobile robot is 1.4kg including links, various IAQ sensors, motors, and battery. The gait and turning speed of the mobile robot was measured at 3.75 cm/sec and 14.13 rad/sec. The maximum height where the robot leg could reach was 33 mm, but the mobile robot was able to overcome the bumps up to 24 mm.

The Korea Cohort Consortium: The Future of Pooling Cohort Studies

  • Lee, Sangjun;Ko, Kwang-Pil;Lee, Jung Eun;Kim, Inah;Jee, Sun Ha;Shin, Aesun;Kweon, Sun-Seog;Shin, Min-Ho;Park, Sangmin;Ryu, Seungho;Yang, Sun Young;Choi, Seung Ho;Kim, Jeongseon;Yi, Sang-Wook;Kang, Daehee;Yoo, Keun-Young;Park, Sue K.
    • Journal of Preventive Medicine and Public Health
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    • v.55 no.5
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    • pp.464-474
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    • 2022
  • Objectives: We introduced the cohort studies included in the Korean Cohort Consortium (KCC), focusing on large-scale cohort studies established in Korea with a prolonged follow-up period. Moreover, we also provided projections of the follow-up and estimates of the sample size that would be necessary for big-data analyses based on pooling established cohort studies, including population-based genomic studies. Methods: We mainly focused on the characteristics of individual cohort studies from the KCC. We developed "PROFAN", a Shiny application for projecting the follow-up period to achieve a certain number of cases when pooling established cohort studies. As examples, we projected the follow-up periods for 5000 cases of gastric cancer, 2500 cases of prostate and breast cancer, and 500 cases of non-Hodgkin lymphoma. The sample sizes for sequencing-based analyses based on a 1:1 case-control study were also calculated. Results: The KCC consisted of 8 individual cohort studies, of which 3 were community-based and 5 were health screening-based cohorts. The population-based cohort studies were mainly organized by Korean government agencies and research institutes. The projected follow-up period was at least 10 years to achieve 5000 cases based on a cohort of 0.5 million participants. The mean of the minimum to maximum sample sizes for performing sequencing analyses was 5917-72 102. Conclusions: We propose an approach to establish a large-scale consortium based on the standardization and harmonization of existing cohort studies to obtain adequate statistical power with a sufficient sample size to analyze high-risk groups or rare cancer subtypes.

Major environmental factors and traits of invasive alien plants determining their spatial distribution

  • Oh, Minwoo;Heo, Yoonjeong;Lee, Eun Ju;Lee, Hyohyemi
    • Journal of Ecology and Environment
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    • v.45 no.4
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    • pp.277-286
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    • 2021
  • Background: As trade increases, the influx of various alien species and their spread to new regions are prevalent and no longer a special problem. Anthropogenic activities and climate changes have made the distribution of alien species out of their native range common. As a result, alien species can be easily found anywhere, and they have nothing but only a few differences in intensity. The prevalent distribution of alien species adversely affects the ecosystem, and a strategic management plan must be established to control them effectively. To this end, hot spots and cold spots were analyzed according to the degree of distribution of invasive alien plants, and major environmental factors related to hot spots were found. We analyzed the 10,287 distribution points of 126 species of alien plants collected through the national survey of alien species by the hierarchical model of species communities (HMSC) framework. Results: The explanatory and fourfold cross-validation predictive power of the model were 0.91 and 0.75 as AUC values, respectively. The hot spots of invasive plants were found in the Seoul metropolitan area, Daegu metropolitan city, Chungcheongbuk-do Province, southwest shore, and Jeju island. Generally, the hot spots were found where the higher maximum temperature of summer, precipitation of winter, and road density are observed, but temperature seasonality, annual temperature range, precipitation of the summer, and distance to river and sea were negatively related to the hot spots. According to the model, the functional traits accounted for 55% of the variance explained by the environmental factors. The species with higher specific leaf areas were more found where temperature seasonality was low. Taller species preferred the bigger annual temperature range. The heavier seed mass was only preferred when the max temperature of summer exceeded 29 ℃. Conclusions: In this study, hot spots were places where 2.1 times more alien plants were distributed on average than non-hot spots (33.5 vs 15.7 species). The hot spots of invasive plants were expected to appear in less stressful climate conditions, such as low fluctuation of temperature and precipitation. Also, the disturbance by anthropogenic factors or water flow had positive influences on the hot spots. These results were consistent with the previous reports about the ruderal or competitive strategies of invasive plants instead of the stress-tolerant strategy. The functional traits are closely related to the ecological strategies of plants by shaping the response of species to various environmental filters, and our result confirmed this. Therefore, in order to effectively control alien plants, it is judged that the occurrence of disturbed sites in which alien plants can grow in large quantities is minimized, and the river management of waterfronts is required.

Enhancement of Electrochemical Performance of Cathode by Optimizing Laccase-Carbon Nanotubes Layers for Enzymatic Fuel Cells (Laccase-탄소나노튜브 적층을 통한 효소 연료전지의 cathode 성능 향상)

  • Wang, Xue;Kim, Chang-Joon
    • Korean Chemical Engineering Research
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    • v.60 no.4
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    • pp.550-556
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    • 2022
  • The performance of enzymatic fuel cells that convert chemical energy contained in various organic molecules such as sugar, alcohol, organic acids, and amino acids into electrical energy is greatly affected by the cathode as well as the anode. This study aimed to develop a laccase-based cathode with high performance. An enzyme composite composed of an laccase, redox mediator, and carbon nanotubes was immobilized on the surface of electrode in multiple layers, and the effect of the number of layers and the presence or absence of carbon nanotubes on electrode performance was investigated. As the number of layers of the enzyme-mediator (Lac-(PVI-Os-dCl)) on the electrode surface increased, the amount of reduction current generated at the electrode increased. The enzyme-carbon nanotube-mediator composite electrode (Lac-SWCNTs-(PVI-Os-dCl)) generated a current 1.7 times greater than that of the Lac-(PVI-Os-dCl). It was found that the largest amount of current (10.1±0.1 µA) was generated in the electrode composed of two layers of Lac-(PVI-Os-dCl) and two layers of Lac-SWCNTs-(PVI-Os-dCl) in the evaluation of electrodes with different ratio of Lac-SWCNTs-(PVI-Os-dCl) and Lac-(PVI-Os-dCl). The maximum power density of the cell using the cathode composed of a single layer of Lac-(PVI-Os-dCl) and the cell using the optimized cathode were 0.46±0.05 and 1.23±0.04 µW/cm2, respectively. In this study, it was demonstrated that the performance of cathode and the enzymatic fuel cell using the same can be improved by optimizing the layers of composites composed of laccase, redox mediator, and carbon nanotubes on the electrode surface.

Analysis of the Sports Welfare Service Delivery System for the Sports Vouchers (스포츠강좌이용권의 스포츠복지서비스 전달체계 분석)

  • Choi, Hee-Dong
    • Journal of Korea Entertainment Industry Association
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    • v.14 no.5
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    • pp.131-146
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    • 2020
  • This research is based on social flow that is in need of sports welfare that diagnoses the delivery system of sports program pass that is typical business of national sports welfare services and operation structure, and analyze the supplier, operator, beneficiary and all that is related to business from multilateral aspects, therefore seek for operation systems for provision systems of sports welfare services. To clearly grasp the operating mechanisms of service provision system that is happening in real field, there were in-depth interview done by the 18 people of suppliers, operators, and beneficiaries that are the main participants of business, and through which drew an ideal agreed point for sports welfare services to get in the right direction. The result of this study is as following: First, based on the limited government budget for the compilation of budget for the business of sports welfare services it is found that there is need of constructing a pragmatic service provision system that can bring maximum of efficiency. Second, voucher that was introduced for market logic application and greater transparency of the business of sports welfare services has a complex structure that it is in need of simplification of structure which that is well fit with its characteristics. Third, for convenience enlargement in administration and management, make management policy of provision system be reflected and therefore enlarge the independence of management and secure the power of negotiation regarding fee savings through centralized budget management.

Calculation of optimal design flood using cost-benefit analysis with uncertainty (불확실성이 고려된 비용-편익분석 기법을 도입한 최적설계홍수량 산정)

  • Kim, Sang Ug;Choi, Kwang Bae
    • Journal of Korea Water Resources Association
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    • v.55 no.6
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    • pp.405-419
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    • 2022
  • Flood frequency analysis commonly used to design the hydraulic structures to minimize flood damage includes uncertainty. Therefore, the most appropriate design flood within a uncertainty should be selected in the final stage of a hydraulic structure, but related studies were rarely carried out. The total expected cost function introduced into the flood frequency analysis is a new approach for determining the optimal design flood. This procedure has been used as UNCODE (UNcertainty COmpliant DEsign), but the application has not yet been introduced in South Korea. This study introduced the mathematical procedure of UNCODE and calculated the optimal design flood using the annual maximum inflow of hydroelectric dams located in the Bukhan River system and results were compared with that of the existing flood frequency. The parameter uncertainty was considered in the total expected cost function using the Gumbel and the GEV distribution, and the Metropolis-Hastings algorithm was used to sample the parameters. In this study, cost function and damage function were assumed to be a first-order linear function. It was found that the medians of the optimal design flood for 4 Hydroelectric dams, 2 probability distributions, and 2 return periods were calculated to be somewhat larger than the design flood by the existing flood frequency analysis. In the future, it is needed to develop the practical approximated procedure to UNCODE.

Study on the Identification of Ship Maneuverability Required for Navigational Officers based on AHP Analysis (AHP 분석 기반 항해사 필요 선박조종성능 식별 연구)

  • Kang, Suk-Young;Ahn, Young-Joong;Yu, Yong-Ung;Lee, Yun-Sok
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.5
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    • pp.800-808
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    • 2022
  • The International Maritime Organization adopted the interim standards for ship maneuverability in November 1993 for preventing collision of ships at sea and for protecting the marine environment, and based on the accumulated data, in December 2002, the established standards for ship maneuverability were adopted. However, the standards adopted are those at full load, even keel, and at least 90 % of the ship speed at 85 % of the ship's maximum power. Moreover, these standards have limitations in providing information on maneuverability under actual navigational conditions. Therefore, in this study, frequency analysis AHP analysis techniques were studied by consulting navigational officers, captains, and experts, who have significant knowledge on ship maneuverability, utilization of the current standards, and the information necessary for the operation of the actual ship. The results of this study confirmed that the necessary information on maneuverability for the navigational officer operating the vessel is information about the turning circle at a small angle of 5°-10° and z-test information at maneuvering speed, not sea speed. Additionally, in relation to speed control, additional information on deceleration inertia and acceleration inertia is needed than the information on the stopping ability at sea speed and full loaded condition. The derived results are considered to be useful as basic data for preparing guidelines for ship maneuverability necessary for navigational of icers who operate ships.