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Nickel Catalysts Supported on Ash-Free Coal for Steam Reforming of Toluene (무회분탄에 분산된 니켈 촉매의 톨루엔 수증기 개질)

  • PRISCILLA, LIA;KIM, SOOHYUN;YOO, JIHO;CHOI, HOKYUNG;RHIM, YOUNGJOON;LIM, JEONGHWAN;KIM, SANGDO;CHUN, DONGHYUK;LEE, SIHYUN
    • Journal of Hydrogen and New Energy
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    • v.29 no.6
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    • pp.559-569
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    • 2018
  • Catalytic supports made of carbon have many advantages, such as high coking resistance, tailorable pore and surface structures, and ease of recycling of waste catalysts. Moreover, they do not require pre-reduction. In this study, ash-free coal (AFC) was obtained by the thermal extraction of carbonaceous components from raw coal and its performance as a carbon catalytic support was compared with that of well-known activated carbon (AC). Nickel was dispersed on the carbon supports and the resulting catalysts were applied to the steam reforming of toluene (SRT), a model compound of biomass tar. Interestingly, nickel catalysts dispersed on AFC, which has a very small surface area (${\sim}0.13m^2/g$), showed higher activity than those dispersed on AC, which has a large surface area ($1,173A/cm^2$). X-ray diffraction (XRD) analysis showed that the particle size of nickel deposited on AFC was smaller than that deposited on AC, with the average values on AFC ${\approx}11nm$ and on AC ${\approx}23nm$. This proved that heteroatomic functional groups in AFC, such as carboxyls, can provide ion-exchange or adsorption sites for the nano-scale dispersion of nickel. In addition, the pore structure, surface morphology, chemical composition, and chemical state of the prepared catalysts were analyzed using Brunauer-Emmett-Taylor (BET) analysis, transmission electron microscopy (TEM), scanning electron microscopy (SEM), x-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, and temperature-programmed reduction (TPR).

Trends of Korean Medicine Conservative Treatment Using Low Back Pain Patients Registry Data: Analysis of Medical Records of 7 Korean Medical Hospital (요통 환자 레지스트리 데이터를 통한 한의 보존적 치료 경향: 7개 한방병원 의무기록 분석)

  • Lee, Kang-Joon;Oh, Min-Seok;Lee, Eun-Jung;Shin, Byung-Cheul;Hwang, Eui-Hyoung;Kim, Soon-Joong;Cha, Yun-Yeop;Ko, Youn-Seok;Song, Yun-kyung
    • Journal of Korean Medicine Rehabilitation
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    • v.29 no.3
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    • pp.87-101
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    • 2019
  • Objectives The purpose of this study is to investigate characteristics of low back pain patients and trends of Korean medicine conservative treatment effects of low back pain patients by registry data. Methods A total of 78 patients were analyzed, statistical analysis was performed using a generalized linear model. The comparison between groups was performed using independent two samples t-test or Wilcoxon rank sum test according to the distribution of normality. Before and after the treatment effects, ANOVA and Kruskal-Wallis method were used for the comparison, Sheffe method was used for the post test. Results The average age of hospitalized patients was 31.8 years old and out-patient department (OPD) patients was 44.9 years old. Lots of OPD patients and hospitalized patients were classified to 'Lumbago due to Coexist Qu Stagnation and Bloos Stasis'. Both OPD patients and hospitalized patients classified to 'Lumbago due to Coexist Qu Stagnation and Bloos Stasis' showed statistically significant decrease in RMDQ (Roland-Morris disability questionnaire) and NRS (numeric rating scale) on 1 month and 3 month after clinical research start date. Comparing the treatment effects of Chuna manual therapy, both Chuna group and non-Chuna group showed statistically significant decrease in RMDQ and NRS on discharge date, 1 month and 3 month after clinical research start date. Conclusions We expect that a larger scale registry study will be carried out to provide a higher level of basis for the Korean medical treatment of low back pain.

The Validity of Activity Participation Assessment for School-Age Children (학령기 아동을 위한 활동 참여 평가도구(Activity Participation Assessment)의 타당도 연구)

  • Kim, Se-Yun
    • The Journal of Korean Academy of Sensory Integration
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    • v.17 no.1
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    • pp.19-29
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    • 2019
  • Objective : The aim of this study was to verify validity of the Activity Participation Assessment for school-age children. Methods : A questionnaire consisting of 30 items from the APA, 75 items from the PACS, and 55 items from the CAPE was administered to elementary school students. A total of 207 questionnaires were analyzed. Confirmatory factor analysis was performed to confirm the construct validity of the APA. Convergence validity and discriminant validity were verified with the average variance extracted (AVE) and the square of the correlation coefficient. The discriminant validity was the Pearson correlation coefficient of the APA, PACS, and CAPE. Results : The results of the analysis were as follows: 1) For construct validity, the goodness of fit of the modified hierarchical second-order factor model was found to be appropriate (p < .001), 2) For convergent validity, the AVE was higher than .50 for all latent variables, 3) For discriminant validity, the AVE of the latent variable was greater than the square of the correlation coefficient (0.239), 4) For concurrent validity, the correlation between the total sum of the APA and PACS scores showed a positive correlation in all domains, and the correlation coefficient ranged from .303 to .647 at a statistically significant level (p < .01), 5) The correlation coefficient between the total sum of the APA and CAPE scores was .490 for recreational activities, .329 for physical activities, .571 for social activities, .401 for skill-based activities, and .390 for self-improvement activities. All domains showed a positive correlation, and were statistically significant (p < .01). Conclusion : APA can be used as a valid assessment tool to measure the participation of school aged children.

An Analysis of the Determinants of Employment Productivity in Korean Transportation Industry Using Korea Labor and Income Panel Study (한국노동패널자료를 활용한 국내 운송업 고용생산성 결정요인 분석)

  • So, Ae-rim;Shin, Seung-sik
    • Journal of Korea Port Economic Association
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    • v.35 no.1
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    • pp.57-76
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    • 2019
  • This study deals with the determinants of employment productivity of transportation labor, who are the main agents of the transportation industry that has made significant contributions to our country's industrial development. The study selected the determinants of employment productivity using the Korea Labor and Income Panel Study data, and analyzed the effects of various factors using panel logistic regression, panel OLS model, and panel robust regression. The results were as follows. First, a more positive effect was shown when employees held a regular job, had a "high level of education", "joining the labor union" and "experiencing vocational training". Second, in the case of job security, having a "high level of education" and "joining the labor union" showed a more positive effect; further, job security was higher for employees who worked in a "big company" or were "married". Third, in the case of higher income productivity, higher values of "age", "academic ability" and "company size" had a more positive effect, whereas larger values of "education" and "health condition except job training" had a negative one. Fourth, in the case of job satisfaction, "female", "joining the labor union" and having a higher "income" or "job security" led to higher satisfaction and a better "health condition compared to an average person". Further, a higher "overall life satisfaction" and "economic level" led to lower job satisfaction. The analysis of the determinants of employment productivity of transportation business and seeking for improvement plan is expected to improve the employment productivity in the transportation business.

Research on Vibration and Noise Characteristics of Steel Plate Girder Bridge with Embedded Rail Track System (레일매립궤도 시스템이 적용된 판형교의 진동 및 소음특성에 대한 연구)

  • Park, Jeung-Geun;Koh, Hyo-In;Kang, Yun-Suk;Jeong, Young-Do;Yi, Seong-Tae
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.23 no.1
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    • pp.94-101
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    • 2019
  • Most of the existing rail structures have undergone a lot of aging since a considerable period of time has passed from completion. In particular, among existing railway bridges, many of the plate girder bridges are older bridges that have lived 40 to 60 years or more. Since the treadmill is directly connected to the girder without the ballast, the running load of the vehicle is directly transmitted to the bridge. Therefore, the shock and noise applied to the bridge are larger than those of the ballast bridge, and the dynamic shock and vibration are also relatively large. Therefore, it is very urgent to develop appropriate maintenance, repair and reinforcement technology for existing steel plate bridge. In this study, the authors introduced the characteristics of embedded rail (ERS) developed for improving the performance of the existing plate girder bridge and the techniques solving the vibration and noise problems. In order to evaluate the vibration and noise reduction performance of ERS, a non-ballast plate girder bridge with 5m length of sleepers installed and a plate girder bridge with ERS were fabricated. And, then, the vibration response generated under the same excitation condition was measured and analyzed. Also, the radiated noise analysis was performed using the vibration response data obtained from the experiment as the input data of the acoustic analysis model. As a result of experiments and analyses, it was confirmed that the plate girder bridge's vibration using ERS was reduced by 15.0~18.8dB and the average noise was reduced by 7.7dB(A) more than the non-ballast bridge.

A Study on The Influence Factors of Self-Efficacy, Job Performance, and Job Satisfaction of University Hospital Nurses (대학병원간호사의 자기효능감, 업무수행능력이 직무만족도에 미치는 영향요인)

  • Kim, Mi-Young;Lee, Hye-Kyung
    • Journal of the Korean Applied Science and Technology
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    • v.36 no.3
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    • pp.726-736
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    • 2019
  • The purpose of this study is to investigate the effect of University hospital nurses' self-efficacy and job performance on job satisfaction. The subjects of this study were 130 nurses working at a university hospital in C city and collected data using structured questionnaires. The collected data were analyzed using mean, standard deviation, t-test, ANOVA, Pearson's correlation and multiple regression analysis using spss 25.0. The results showed that the self-efficacy was 3.24 points for the average score, 2.74 points for the job performance, and 3.10 points for the job satisfaction. Self-efficacy, job performance, and job satisfaction were statistically correlated. The factors affecting job satisfaction were self-efficacy (${\beta}=.39$, p<.001), age at 30~34 years (${\beta}=-.27$, p=.001), Operating Room(${\beta}=-.17$, p=.029), Medical ward (${\beta}=-.17$, p=.025) and unmarried (${\beta}=-.20$, p=.012) and the explanatory power of the model was 30.4%. Based on the results of this study, it is necessary to develop a program to improve the job satisfaction considering the self-efficacy, age, working department of hospital nurse.

Deep Learning Structure Suitable for Embedded System for Flame Detection (불꽃 감지를 위한 임베디드 시스템에 적합한 딥러닝 구조)

  • Ra, Seung-Tak;Lee, Seung-Ho
    • Journal of IKEEE
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    • v.23 no.1
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    • pp.112-119
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    • 2019
  • In this paper, we propose a deep learning structure suitable for embedded system. The flame detection process of the proposed deep learning structure consists of four steps : flame area detection using flame color model, flame image classification using deep learning structure for flame color specialization, $N{\times}N$ cell separation in detected flame area, flame image classification using deep learning structure for flame shape specialization. First, only the color of the flame is extracted from the input image and then labeled to detect the flame area. Second, area of flame detected is the input of a deep learning structure specialized in flame color and is classified as flame image only if the probability of flame class at the output is greater than 75%. Third, divide the detected flame region of the images classified as flame images less than 75% in the preceding section into $N{\times}N$ units. Fourthly, small cells divided into $N{\times}N$ units are inserted into the input of a deep learning structure specialized to the shape of the flame and each cell is judged to be flame proof and classified as flame images if more than 50% of cells are classified as flame images. To verify the effectiveness of the proposed deep learning structure, we experimented with a flame database of ImageNet. Experimental results show that the proposed deep learning structure has an average resource occupancy rate of 29.86% and an 8 second fast flame detection time. The flame detection rate averaged 0.95% lower compared to the existing deep learning structure, but this was the result of light construction of the deep learning structure for application to embedded systems. Therefore, the deep learning structure for flame detection proposed in this paper has been proved suitable for the application of embedded system.

A Study on the Planting Improvement and Original Landscape of Gyeonghoeru Area in Gyongbokkung Palace (경복궁 경회루 권역의 식생경관원형과 개선에 관한 연구)

  • Kim, Choong-sik;Jeong, Seul-ki
    • Journal of the Korean Institute of Landscape Architecture
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    • v.46 no.6
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    • pp.17-25
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    • 2018
  • This study was conducted to calculate the optimum height of trees, estimating a model for the prediction of tree growth for the landscape improvement of the Gyeonghoeru area. For the verification of measures for management, this study conducted a photographic survey of the Gyeonghoeru area and used the Pressler's formula to examine the growth rate of the pine forest of Mansesan. The results of the study are as follows. First, as a result of a field survey and landscape analysis, trees in the Gyeonghoeru area are large ones with more than a diameter at breast height of 30cm, except for weeping cherry trees and persimmon trees, and especially, it is necessary to manage them or replace with small trees through the landscape of Mansesan, which screens the landscape and pruning the trees in the terraced flower garden in the north. Second, as a result of a measurement of the growth rate of trees, for 10 years on average, they grew up by 14% in source diameter and 5% in tree height 5% in south of Mansesan and by 7% in source diameter and 2.4% in tree height in the north of Mansesan. Furthermore, when a simulation was prepared based on the measured growth rate of trees, it was found out that 20 years later, on the landscape on the second floor of Gyeonghoeru, the pine forest of Mansesan would cut off the skyline of Mt. Inwang-san. Third, this study analyzed a landscape improvement simulation and proposed a plan for tree management to take a view of the landscape of the Gyeonghoeru area. This study has a significance that it drew an efficient planting maintenance policy, considering the landscape characteristics of the Gyeonghoeru area.

A Study on the Factors Influencing Burnout of Psychiatric Ward Nurses -Violence Experience, Violence Coping, Social Support- (정신과병동 간호사의 소진 영향 요인에 관한 연구 -폭력경험, 폭력대처, 사회적지지)

  • Seo, Jeong-Won;Kang, Mi-Ran;Je, Nam-Joo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.7
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    • pp.393-405
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    • 2019
  • This study is descriptive survey research to find out factors which violence experience, violence coping and social support affect. This study aims at reducing burnout of psychiatry nurses and founding problem-oriented violence handling standardized intervention. The subjects were 204 nurses who have worked for more than a year in a hospital. The data collection period was conducted with structured survey from July 1, 2018 to August 31, 2018. Collected data was analysed with average, standard deviation, t-test, ANOVA, Pearson's Correlation confident, Multiple Regression and this data will go to by SPSS. The results of the study were as follows. 92.2% of psychiatry nurses are experiencing verbal violence, 92.2% are experiencing physical threat and 75.5% are experiencing physical violence. Relations between violence experience and violence coping(r=0.15. p<.027), violence experience and burnout(r=0.16, p<.017) were positive correlation. Relation between violence coping and social support(r=0.30, p<.001) was positive correlation, and social support and burnout(r=-0.28, p<.001) was negative correlated. Also we found out that nursing job satisfaction, social support and physical violence experience affect burnout. Which shows model's explanatory power was 33.3%. Therefore preventive discipline which can reduce violence experience of psychiatry nurses, founding systems to reinforce social support and creating circumstance where nursing job satisfaction can increase will help reduce burnout and serve better nursing.

The Effect of Social Support and Resilience on Sick Role Behavior of Hemodialysis Patients (혈액투석환자의 사회적지지, 회복탄력성이 환자역할행위 이행에 미치는 영향)

  • Noh, Sung Bae;Lim, HyoNam;Lee, Mi Hyang;Kim, Doo Ree
    • Journal of the Korea Convergence Society
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    • v.10 no.5
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    • pp.385-395
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    • 2019
  • This was a descriptive study to investigate the effect of social support and resilience on sick role behaviors of hemodialysis patients, and aims to provide base data on nursing intervention programs for improving the sick role behaviors of hemodialysis patients. The study subjects was patients with chronic kidney disease undergoing hemodialysis treatment at a general hospital in D city. The final analysis has been made on 131 questionnaires. The average of social support score was $3.93{\pm}0.84$, and resilience score was $2.67{\pm}0.80$. At last sick role behavior score was $3.99{\pm}0.80$. According to the analysis on the correlations among the study subjects' social support, resilience and sick-role behaviors, the social support had statistically and significantly positive correlation. In regression analysis, frequency of dialysis, social support and resilience have appeared to be the variables influencing sick role behavior, and the explanatory power of this model is 44.0%.