• Title/Summary/Keyword: $k_0$ factor

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Analysis on the Effects of the Heat Loss Coefficient on the Operation Time of Sprinkler in Compartment Fire (구획 화재에서 스프링클러 열 손실계수 변화에 따른 작동 시간 분석)

  • You, Woo Jun
    • Fire Science and Engineering
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    • v.32 no.5
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    • pp.34-39
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    • 2018
  • In this study, the experiment conditions for the variation of heat release rate in compartment space were constructed to analyze the effects of fire spread and the operation time of sprinkler in accordance with the heat loss of the sprinkler's heat element. The compartment composed of fire board (width = 0.3 m, height = 0.5 m, length = 3.0 m), are manufactured to measure the temperature distributions in the inner space, the mass loss rate and heat release rate during the experiment of N-heptane pool fire test. Also, the operation time of sprinkler is analyzed with the installation of sprinkler and C-factor using Fire Dynamics Simulator Ver.6 under the experiment conditions. The results show that the operation time of sprinkler, which has RTI $100(m{\cdot}s)^{0.5}$ operating temperature $70^{\circ}C$, is 30 s~60 s for C-factor = 0 and 1, 62 s~92 s for C-factor = 3, and 120 s over for C-factor = 5, respectively.

Festival search factor analysis for festival application users (축제 앱 사용자를 위한 축제 검색 요인분석)

  • Lee, Chang-keun;Kim, Soon-gohn
    • Journal of Digital Contents Society
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    • v.16 no.6
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    • pp.883-892
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    • 2015
  • This paper was conducted to improve existing festival apps that present information in a one-dimensional and unengaging manner by analyzing the factors for festival quality factor from satisfaction evaluation items in culture and tourism festival evaluation reports as well as international and domestic studies. An exploratory factor analysis generated a KMO value of 0.821. After eliminating factors with factor loadings lower than the standard value, the factors of accessibility, promotion and information, contents of events, festival products, food, and amenities were extracted. Reliability was gauged using Cronbach's ${\alpha}$(Alpha), which was calculated to be 0.816. In the confirmatory factor analysis, the p value in the chi-square test was 0.289 while CMIN/DF was 1.100. The fit indices of GFI, AGFI, CFI, NFI, and IFI were all higher than the 0.9 mark while RMSEA was 0.018.

The Effect of Sommelier Service Quality on Customer's Emotional Response and Revisit Intention (소믈리에 서비스품질이 고객의 감정반응과 재방문의도에 미치는 영향)

  • Jin, Yang-Ho;Park, Mi-Young;Ryu, Ji-Won
    • Culinary science and hospitality research
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    • v.19 no.1
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    • pp.70-84
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    • 2013
  • The study aimed at grasping the factors of sommelier service quality and analyzing how customers' emotional responses based on sommelier service quality had a big impact on the revisit intention for the customers who received sommelier service from food service industries located in Seoul. The findings are as follows. The effects of sommelier service quality on positive emotions were respectively significant in specialty factor(${\beta}$=.257, p<0.001), reliability factor(${\beta}$=.314, p<0.001), and responsiveness factor(${\beta}$=.387, p<0.001). And the effect on negative emotions was significant in specialty factor(${\beta}$=-.178, p<0.05). Meanwhile, the result of the effect on the revisit factor of sommelier service quality was significant in reliability factor(${\beta}$=.286, p<0.001). And the effects of customers' emotional response on revisit factor were significant in positive emotion factor(${\beta}$=.350, p<0.001) and negative emotion factor(${\beta}$=-.195, p<0.01) respectively. As the emotional responses based on sommelier service quality had a great impact on customers' revisit intention according to positive or negative emotions, it is necessary for food service industry operators to improve customer satisfaction with consolidating the factors to give customers positive emotions which eventually can lead them to revisit wine restaurants.

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A Study on the Satisfaction and Stress Factors of Clinical Practice for Dental Hygiene Students (일부 치위생학과 학생들의 병원실습 만족도와 스트레스 요인에 관한 연구)

  • Yoo, Ja-Hea;Kim, Jung-Hee
    • Journal of dental hygiene science
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    • v.16 no.1
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    • pp.62-69
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    • 2016
  • The purpose of this study was investigate the relationship between the degree of satisfaction of the clinical practice and the stress factors for dental hygiene students. Dental hygiene students to 232 people from May 21, 2012 to June 22, 2012 and analyzed using by SPSS for Windows ver. 12.0 program. Regarding the stress factors, by the school system, all the factors, including the environmental factor, the role factor, the interpersonal relationships factor, the ideal and value factor, and the Brief Encounter Psychosocial Instrument (BEPSI) were higher in the 3-year system than in the 4-year system (p<0.01). Regarding the stress factors according to the degree of satisfaction regarding the practices, all the factors were high when unsatisfied. Among these, the environmental factor was the highest (p<0.001). According to the practice organization, the environmental factor was the highest among the university dental hospital. The interpersonal relationship factor and the ideal and value factor were the highest among the dental hospitals. The role factor and the BEPSI were the highest among the dental clinics (p<0.01). When the hospital atmosphere was bad, the environmental factor was the highest (p<0.001). As a result of analyzing the correlations between the stress factors of the hospital practices, there were the positive correlations among the environment, the roles, the interpersonal relationship, the ideals and values, and the BEPSI (p<0.01). The stress factor that showed the biggest influence on the BEPSI was interpersonal relationships. In the clinical practice, because of the unfamiliar environment and the insufficiency of the interpersonal relationships, the stress indices of the students can be higher than at ordinary times. I believe that, as such, a systematic management plan for the clinical practice for raising the ability of the students to cope with the stress by themselves must be prepared.

The Antecedents of Coffee Satisfaction by Lifestyle Segments for Korean and Chinese University Students in Korea (국내 한국인 및 중국인 대학생의 라이프스타일별 커피 만족도 선행요인 분석)

  • Chung, Hye-Kyung;Kim, Hye-Young;Lee, Hae-Young
    • Korean Journal of Community Nutrition
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    • v.16 no.6
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    • pp.782-793
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    • 2011
  • The purposes of this study were to classify university students by their lifestyle and to investigate the relationships between lifestyle and coffee satisfaction. The survey had been undertaken for 360 Korean and Chinese university students in Daejeon from November to December 2009. A total of 242 usable questionnaires were received with 67.2% response rate. The statistical analysis was performed by the SPSS 18.0 package program. Lifestyles of subjects, based on AIO (Activities, Interests, Opinions) method and factor analysis, were segmented into 2 groups of "outgoing activity" (n = 137) and "introverted devotion" (n = 105). "Outgoing activity" group exhibited highly health-oriented (p < 0.001) and convenience-oriented (p < 0.001) characteristics, but "introverted devotion" group showed highly goal-oriented (p < 0.01) and safety-oriented (p < 0.01) features. Comparing to "introverted devotion" group, "outgoing activity" group showed higher intake of coffee (p < 0.01) and more expense for beverage (p < 0.01). Three factors were extracted from 15 coffee quality attributes by factor analysis; "fundamentals", "supplement" and "inducement". These factors were positively correlated with coffee satisfaction according to lifestyle groups (p < 0.01). For "outgoing activity" group, 'fundamentals' was independent factor for satisfaction on coffee in coffee house (${\beta}$ = 0.268, p < 0.05) and canned or bottled coffee (${\beta}$ = 0.314, p < 0.01), and "supplement" was independent factor for satisfaction on coffee in vending machine (${\beta}$ = 0.235, p < 0.05). For "introverted devotion" group, "inducement" was independent factor for satisfaction on coffee in vending machine (${\beta}$ = 0.238, p < 0.001). These results provide an understanding for lifestyles of coffee consumers and give an insight into differentiated marketing plans for coffee industry.

KCT첨가에 따른 $(Na,K)NbO_3$ 세라믹스의 압전특성

  • No, Jeong-Rae;Lee, Yu-Hyeong;Ryu, Ju-Hyeon;Yun, Hyeon-Sang
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.11a
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    • pp.93-93
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    • 2009
  • In this study, in order to develop excellent lead-free composition ceramics for piezoelectric transformer, $(K_{5.4}Cu_{1.3}Ta_{10}O_{29})$ added $(K_{0.5}Na_{0.5}](Nb_{0.97}Sb_{0.03})O_3$ were fabricated using conventional mixed oxide method. At the 0.9mol% KCT added specimen, electromechanical coupling factor(kp) and mechanical quality factor ($Q_m$) showed the optimal values of 0.437 and 727.07, respectively, for piezoelectric transformer application.

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Effect of ZnO on Low Temperature Sintering of PMN-PNN-PZT Ceramics (ZnO가 PMN-PNN-PZT 세라믹스의 저온소결에 미치는 영향)

  • Lee, Sang-Ho;Yoo, Ju-Hyun;Hong, Jae-Il;Ryu, Sung-Lim
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.11a
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    • pp.32-33
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    • 2006
  • In this study, in order to develop multilayer ceramic actuator for ultrasonic nozzle and ultrasonic vibrator, PMN-PNN-PZT ceramics were fabricated using $Li_2CO_3$. $Na_2CO_3$ and ZnO as sintering aids. And then, their piezoelectric and dielectric properties according to the amount of ZnO addition were investigated. The addition of ZnO improved density, dielectric constant, electromechanical coupling factor, mechanical quality factor and piezoelectric d constant of PMN-PNN-PZT ceramics due to the increase of sinterability and accepter doping effect. Electromechanical coupling factor and mechanical quality factor of PMN-PNN-PZT ceramics increased with ZnO amount up to 0.4wt% and then decreased. At the sintering temperature of $900^{\circ}C$ and 0.4wt% ZnO addition, density, dielectric constant, electromechanical coupling factor, mechanical quality factor and piezoelectric d constant showed the optimum value of 7.876g/$cm^2$, 1299, 0.612, 1151 and 369pC/N, respectively.

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Analysis of Coagulation Factor Activity of Normal Adults with APTT Limit Range (APTT에서 경계치에 속한 정상 성인의 혈액응고인자 활성도 분석)

  • Kwon, Eui-Hoon;Koo, Bon-Kyung;Bang, Sung-Hwan;Kim, Hee-Jin;Cho, Young-Kuk
    • Korean Journal of Clinical Laboratory Science
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    • v.47 no.4
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    • pp.237-242
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    • 2015
  • The coagulation factor activity compared two groups of the lower 10% (29.1~30.9 sec) and the upper 10% (38.0~41.9 sec) of the normal reference range of aPTT. The aim of this study was to investigate the influence of sex, age, and ABO blood type on coagulation factor activity. There was significant difference in the activity of the coagulation factor assay based on age. The VIII (p<0.0001) and IX (p=0.0050) in the lower group of samples from those over sixty years of age is higher than from those under sixty. In contrast, XII (p=0.0285) for samples over sixty was lower than for samples under sixty. While in the upper group V (p=0.0219), VIII (p=0.0005), and IX (p=0.0014) for samples from the over sixty group was higher than those under sixty. In the case of activity of coagulation factor between O and non-O blood type, VIII (p<0.001) activity of the non-O blood type was higher than that of the O blood type in the both groups. The XII (p=0.016) activity of non-O blood type was lower than that of O blood type in the upper group. According to the multiple logistic regression analysis, when other variables are under the same conditions between lower and upper groups, there is a strong possibility for the lower group when activity of V (p=0.001), VIII (p<0.001), X (p<0.001) and XII (p<0.001) is increased. Furthermore, there is also a strong possibility of upper group when activity of II (p=0.004) and IX (p=0.012) is increased. However, no significant difference in between sex, age and XI was observed.

The Korean Repeatable Battery for the Assessment of Neuropsychological Status-Update : Psychiatric and Neurosurgery Patient Sample Validity

  • Park, Jong-Ok;Koo, Bon-Hoon;Kim, Ji-Yean;Bai, Dai-Seg;Chang, Mun-Seon;Kim, Oh-Lyong
    • Journal of Korean Neurosurgical Society
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    • v.64 no.1
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    • pp.125-135
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    • 2021
  • Objective : This study aimed to validate the Korean version of the Repeatable Battery for the Assessment of Neuropsychological Status Update (K-RBANS). Methods : We performed a retrospective analysis of 283 psychiatric and neurosurgery patients. To investigate the convergent validity of the K-RBANS, correlation analyses were performed for other intelligence and neuropsychological test results. Confirmatory factor analysis was used to test a series of alternative plausible models of the K-RBANS. To analyze the various capabilities of the K-RBANS, we compared the area under the receiver operating characteristic (ROC) curves (AUC). Results : Significant correlations were observed, confirming the convergent validity of the K-RBANS among the Total Scale Index (TSI) and indices of the K-RBANS and indices of intelligence (r=0.47-0.81; p<0.001) and other neuropsychological tests at moderate and above significance (r=0.41-0.63; p<0.001). Additionally, the results testing the construct validity of the K-RBANS showed that the second-order factor structure model (model 2, similar to an original factor structure of RBANS), which includes a first-order factor comprising five index scores (immediate memory, visuospatial capacity, language, attention, delayed memory) and one higher-order factor (TSI), was statistically acceptable. The comparative fit index (CFI) (CFI, 0.949) values and the goodness of fit index (GFI) (GFI, 0.942) values higher than 0.90 indicated an excellent fit. The root mean squared error of approximation (RMSEA) (RMSEA, 0.082) was considered an acceptable fit. Additionally, the factor structure of model 2 was found to be better and more valid than the other model in χ2 values (Δχ2=7.69, p<0.05). In the ROC analysis, the AUCs of the TSI and five indices were 0.716-0.837, and the AUC of TSI (AUC, 0.837; 95% confidence interval, 0.760-0.896) was higher than the AUCs of the other indices. The sensitivity and specificity of TSI were 77.66% and 78.12%, respectively. Conclusion : The overall results of this study suggest that the K-RBANS may be used as a valid tool for the brief screening of neuropsychological patients in Korea.

Quality Verification for Respiratory Gated Proton Therapy (호흡동조 양성자치료의 Quality Verification)

  • Kim, Eun Sook;Jang, Yo Jong;Park, Ji Yeon;Kang, Dong Yun;Yeom, Doo Seok
    • The Journal of Korean Society for Radiation Therapy
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    • v.25 no.2
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    • pp.107-113
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    • 2013
  • Purpose: To verify accuracy of respiratory gated proton therapy by measuring and analyzing proton beam delivered when respiratory gated proton therapy is being performed in our institute. Materials and Methods: The plan data of 3 patients who took respiratory gated proton therapy were used to deliver proton beam from proton therapy system. The manufactured moving phantom was used to apply respiratory gating system to reproduce proton beam which was partially irradiated. The key characteristics of proton beam, range, spreat-out Bragg peak (SOBP) and output factor were measured 5 times and the same categories were measured in the continuous proton beam which was not performed with respiratory gating system. Multi-layer ionization chamber was used to measure range and SOBP, and Scanditronix Wellhofer and farmer chamber was used to measure output factor. Results: The average ranges of 3 patients (A, B, C), who had taken respiratory gated proton therapy or not, were (A) 7.226, 7.230, (B) 12.216, 12.220 and (C) 19.918, 19.920 $g/cm^2$ and average SOBP were (A) 4.950, 4.940, (B) 6.496, 6.512 and (C) 8.486, 8.490 $g/cm^2$. And average output factor were (A) 0.985, 0.984 (B) 1.026, 1.027 and (C) 1.138, 1.136 cGy/MU. The differences of average range were -0.004, -0.004, -0.002 $g/cm^2$, that of SOBP were 0.010, -0.016, -0.004 $g/cm^2$ and that of output factor were 0.001, -0.001, 0.002 cGy/MU. Conclusion: It is observed that the range, SOBP and output factor of proton beam delivered when respiratory gated proton therapy is being performed have the same beam quality with no significant difference compared to the proton beam which was continuously irradiated. Therefore, this study verified the quality of proton beam delivered when respiratory gated proton therapy and confirmed the accuracy of proton therapy using this.

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