• Title/Summary/Keyword: Frequency dependence

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A Study of the Effect of an Avatar Encouraging Drinking in Virtual Reality on Alcohol Craving (가상현실에서의 아바타 음주권유가 갈망감 유발에 미치는 영향에 관한 연구)

  • Choi, You-Kyung;Cho, Sang-Woo;Han, Ki-Wan;Ku, Jeong-Hun;Jung, Young-Chul;Kim, Jae-Jin;Kee, NamKoong;Kim, In-Yong
    • 한국HCI학회:학술대회논문집
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    • 2008.02a
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    • pp.823-828
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    • 2008
  • This study set out investigate what kind of changes would be caused to the craving of alcohol dependent patients by stimuli through virtual reality in the preparation stage for drinking refusal training. With regard to stimulation, it included alcohol exposure, a positive situation, and a negative situation on the basis of drinking encouraging situations(social pressure) known as drinking stimulating situations for alcoholics. The purpose of the study is to provide fundamental materials for the development of new training programs to refuse alcohol and for the examination of the possibility of utilizing virtual reality technology as a new treatment and training tool for alcoholics. To this end, a virtual reality program was conducted involving 12 alcoholics admitted to Severance Mental Health Hospital in Gyeonggi province from December 2006 to September 2007. The data was dealt with various statistic analyses such as frequency analysis, Wilcoxon Matched-pairs Signed-Ranks Test using SPSS/WIN 11.5 The analysis results indicate that avatars encouraging drinking caused more craving than just the background, that the scenes with alcohol exposed caused more craving than the scenes with no alcohol exposed, and that there were no significant changes to craving according to a positive or negative situation. The results confirmed that training sessions using virtual reality presented a situation and environment of drinking pressure that's similar to the actual social pressure and that the virtual reality approach had enormous potential as an effective treatment tool when combined with the existing treatment techniques.

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The Effects of Teamwork by Servant Leadership on Job Attitudes (서번트 리더십에 따른 팀웍이 직무태도에 미치는 영향)

  • Ko, Ki-Chul;Jeon, Hae-Kyung;Cho, Yong-Bum
    • Culinary science and hospitality research
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    • v.18 no.1
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    • pp.91-103
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    • 2012
  • The study model was designed and the hypothesis was drawn based on precedent studies in order to analyze the effects of teamwork by servant leadership on job attitudes, aiming at full-time regular status employees and contract employees lower than the general manager position at special grade hotels in Busan. The SPSS WIN Version 15.0 integrated package for data process was used to verify the hypothesis through frequency analysis, reliability analysis, factorial analysis and regression analysis. As a result of study, the verification result for the effect of servant leadership on communication among the teamwork factors showed that forming sympathy and community and vision meaningfully affects communication; the verification result for the effect of servant leadership on interdependence among the teamwork factors showed that forming community, stewardship, vision factor meaningfully affects interdependence; The verification result for the effect of the teamwork factor on organizational commitment as a job attitude showed communication and interdependence meaningfully affect organizational commitment, one of job attitudes. Cousequently, the leaders in hotel organizations are expected to need a role of personnel management through organizational dependence and participatory management, to draw harmony and corporation among employees and build organizing systems, presenting a clear vision about the future to them.

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The Effects of Rotational Correlation Time of Paramagnetic Contrast Agents on Relaxation Enhancement: Partial Binding to Macromolecules (거대분자에 부분적으로 결합한 상자성 자기공명 조영제의 회전속도가 이완증강에 미치는 영향)

  • 장용민
    • Investigative Magnetic Resonance Imaging
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    • v.3 no.2
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    • pp.159-166
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    • 1999
  • Purpose : To evaluate the effect of rotational correlation time (${\tau}_R$) and the possible related changes of other parameters, ${\tau}_M,{\;}{\tau}_S,{\;}and{\;}(\tau}_V$ of gadolinium (Gd) chelate on T1 relaxation enhancement in two pool model. Materials and Methods : The NMRD (Nuclear Magnetic Relaxation Dispersion) profiles were simulated from 0.02 MHz to 800 MHz proton Larmor frequency for different values of rotational correlation times based on Solomon-Bloembergen equation for inner-sphere relaxation enhancement. To include both unbound pool (pool A) and bound pool (pool B), the relaxivity was divided by contribution from unbound pool and bound pool. The rotational correlation time for pool A was fixed at the value of 0.1 ns, which is a typical value for low molecular weight complexes such as Gd-DTPA in solution and ${\tau}_R$ for pool B was changed from 0.1 ns to 20 ns to allow the slower rotation by binding to macromolecule. The fractional factor of was also adjusted from 0 to 1.0 to simulate different binding ratios to macromolecule. Since the binding of Gd-chelate to macromolecule cab alter the electronic environment of Gd ion and also the degree of bulk water access to hydration site of Gd-chelate, the effects of these parameters were also included. Results : The result shows that low field profiles, ranged from 0.02 to 40 MHz, and dominated by contribution from bound pool, which is bound to macromolecule regardless of binding ratios. In addition, as more Gd-chelate bound to macromolecule, sharp increase of relaxivity at higher field occurs. The NMRD profiles for different values of ${\tau}_S$ show the enormous increase of low field profile whereas relaxivity at high field is not affected by ${\tau}_S$. On the other hand, the change in ${\tau}$V does not affect low field profile but strongly in fluences on both inflection fie이 and the maximum relaxivity value. The results shows a fluences on both inflection field and the maximum relaxivity value. The results shows a parabolic dependence of relaxivity on ${\tau}_M$. Conclusion : Binding of Gd-chelate to a macromolecule causes slower rotational tumbling of Gd-chelate and would result in relaxation enhancement, especially in clinical imaging field. However, binding to macromolecule can change water enchange rate (${\tau}_M$) and electronic relaxation ($T_le$) vis structural deformation of electron environment and the access of bulk water to hydration site of metal-chelate. The clinical utilities of Gd-chelate bound to macromolecule are the less dose requirement, the tissue specificity, and the better perfusion and intravascular agents.

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Deposition Characteristics of Ti-Si-N Films Deposited by Radio Frequency Reactive Sputtering of Various Ratio of Ti/Si Targets in an $N_2$/Ar Ambient (Ti/Si의 조성비율이 다른 타겟을 이용한 sputtered Ti-Si-N 박막의 증착특성 연구)

  • Park, Sang-Gi;Kang, Bong-Joo;Yang, Hee-Jeong;Lee, Won-Hee;Lee, Eun-Goo;Kim, Hee-Jae;Lee, Jae-Gap
    • Korean Journal of Materials Research
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    • v.11 no.7
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    • pp.580-584
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    • 2001
  • We have investigated the deposition characteristics of Ti-Si-N films obtained by rf magnetron sputtering with ratios of Ti/Si targets in an $Ar/N_2$ gas mixture. The growth rate and stoichiometry dependence of the Ti-Si-N films on the ratio of Ti/Si and $N_2$ flow rate ratio were found to be due to the different nitriding rate of Ti and Si targets. Additionally, their different sputtering yield of nitrified Ti and Si make a reason as well. Lowering Si content in the film favored the formation of crystalline TiN, leading to the low resistivity. Increasing N content led to the Ti-Si-N films having a higher density and compressive stress, suggesting that the N content in the film is one of the most important factors determining the diffusion barrier characteristics. In the current work, the optimum process conditions for the formation of efficient diffusion barrier of Ti-Si-N film has successfully obtained by manipulating the Ti/Si ratio of target and $N_2$ flow rate ratio.

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Structure and chemical durability of borosilicate glass-ceramics containing EAF dust (EAF dust가 포함된 붕규산염계 결정화 유리의 구조 및 화학적 내구성)

  • Ahn, Y.S.;Kang, S.G.
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.17 no.2
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    • pp.82-89
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    • 2007
  • Glass-ceramics were fabricated by heat-treating a glass at $700^{\circ}C$/10hr which was obtained by melting a glass frit mixed with $40{\sim}80 wt%$ EAF dust at $1300^{\circ}C$/1hr. Dependence of crystal phase and bonding state change upon a compositional change and heat treatment condition were studied and the results was connected to the toxic characterization leaching procedure (TCLP) test data to investigate a chemical durability of the specimens. Increasing dust in a glass shifted the peak around $1000cm^{-1}$ to the lower frequency which was composed of two vibration peaks for the nonbridging oxygen at $960cm^{-1}$ and the bridging oxygen at $1050{\sim}1060cm^{-1}$. Also, the $B_2O_3$ structure of boroxol ring changed to a tetrhedral-, trigonal- and di-borate with dust addition. The Fe-O peaks in the glass-ceramics were observed which is consitent with XRD results of spinel formation. The surface of glass after TCLP test was severely cracked while there was no cracks on a glass-ceramics after TCLP test so the chemical durability of the glass-ceramics is superior than that of glass. The leaching concentration of Fe for the glass-ceramics containing EAF dust 80 wt% is 1/15 times lower than that of glass. The Zn leaching concentration fur the glass-ceramics containing dust < 70 wt% was higher than that of glass but its trend was reversed for the specimen of dust content > 80 wt% which could be concluded as correlated with occurrence of willemite phase.

ZnO Film Deposition on Aluminum Bottom Electrode for FBAR Filter Applications and Effects of Deposition Temperature on ZnO Crystal Growth (FBAR 필터 응용을 위한 Al 하부전극 상에서 ZnO 박막 증착 및 온도가 ZnO 결정의 성장에 미치는 영향)

  • ;;;Mai Linh
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.2
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    • pp.255-262
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    • 2003
  • In this paper, an investigation on the ZnO film deposition using radio-frequency magnetic sputtering techniques on aluminum bottom electrode for film bulk acoustic wave resonator (FBAR) filter applications and the temperature effects on the ZnO film growth is presented. The investigation on how much impact the actual process temperature may have on the crystal growth is more meaningful if it is considered that the piezoelectricity property of ZnO films plays a dominant role in determining the resonance characteristics of FBAR devices and the piezoelectricity is determined by the degree of the c-axis preferred orientation of the deposited ZnO films. In this experiment, it was found that the growth of ZnO crystals has a strong dependence on the deposition temperature ranged from room temperature to $350^{\circ}C$ regardless of the RF powers applied and there exist 3 temperature regions divided by 2 critical temperatures according to the degree of the c-axis preferred orientation. Overall, below $200^{\circ}C$, ZnO deposition results in columnar grains with a highly preferred c-axis orientation. With this ZnO film, a multilayered FBAR structure could be realized successfully.

Anxiety, Impulsiveness, and Drinking Problems in Employed Women (직장 여성의 불안, 충동성과 음주문제)

  • Lee, Hyun Jae;Han, Doug Hyun;Lee, Young Sik;Kee, Baik Seok;Kwon, Hye Jin;Park, Doo Byung
    • Anxiety and mood
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    • v.7 no.2
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    • pp.73-78
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    • 2011
  • Objectives : This study examined drinking habits, anxiety, and impulsiveness in employed women. Methods : We sampled 925 residents aged over 20 years in Gwanak-gu of Seoul. In the process, we divided subjects into employed women and unemployed women groups and then used the Korean Version of Alcohol Use Disorder Identification Test (AUDIT-K), State-Trait Anxiety Inventory (STAI), and Barratt Impulsiveness Scale (BIS) to identify patterns in subjects' alcohol drinking, anxiety and impulsiveness. Results : Among the 925 respondents, 95.7% drank alcohol, and after the analysis, female problematic drinking ($12{\leq}AUDIT-K{\leq}25$) and alcohol dependence ($AUDIT-K{\geq}26$) was apparent in 61 (9.5%) and 2 respondents (0.3%), respectively. Female respondents who had jobs tended to drink more and exhibit higher ratios of problematic drinking, with a higher exposure to alcohol than those that were unemployed. The psychological attributes related to female respondents' alcohol problems related to state of anxiety and impulsiveness. Employed women respondents also showed a higher state of anxiety and impulsiveness than unemployed women. Conclusion : Controlling the frequency of exposure to alcohol, anxiety, and impulsiveness in employed women should be considered to be crucial controlling factors related to the hazards of excessive drinking.

The Magnetic Properties of Nanocrystalline Fe73.5Cu1Nb3Si15.5B7 Alloy Powder Cores (Fe73.5Cu1Nb3Si15.5B7나노 결정립 합금 분말 코아의 자기적 특성)

  • Noh, T.H.;Choi, H.Y.;Ahn, S.J.
    • Journal of the Korean Magnetics Society
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    • v.14 no.1
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    • pp.7-12
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    • 2004
  • The annealing-temperature dependence of magnetic properties in compressed powder cores being composed of ball-milled F $e_{73.5}$C $u_1$N $b_3$S $i_{15.5}$ $B_{7}$ alloy powders (size 250∼850${\mu}{\textrm}{m}$) and 5 wt% of ceramic insulators has been investigated. When annealed at 5$50^{\circ}C$ for 1 h and so transformed to $\alpha$-Fe phase nanocrystalline structure with the grain size of 11 nm (electrical resistivity : 110 $\mu$$.$cm), the highest effective permeability of 125 and quality factor of 53 were obtained, and the permeability persisted up to about 500 KHz. Further the core loss measured at the frequency of 50 KHz and the induction amplitude of 0.1 T was very low (230 mW/㎤). However the dc bias characteristics was not satisfactory as compared to that of conventional powder core materials(MPP, Sendust etc.). The inferior dc bias property of F $e_{73.5}$C $u_1$N $b_3$S $i_{15.5}$ $B_{7}$ alloy powder cores was attributed to the fact that the size of powder was too large for obtaining the same permeability with that of conventional materials.

A Study on Eating-out Behaviors Depending on Female Customers' Lifestyle in Ulsan.Gyeongnam Province (울산.경남지역 여성고객의 라이프스타일에 따른 외식행동에 관한 연구)

  • Jeon, Yoo-Myeong;Lee, Jong-Ho
    • Culinary science and hospitality research
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    • v.18 no.3
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    • pp.18-31
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    • 2012
  • The current study aimed to analyze data conducting a survey with 211 females in Ulsan Gyeongnam province in order to understand what influence lifestyle types of female customers exert on eating-out behaviors from the perspective of eating-out motivation. So as to achieve research purpose, we conducted factor analysis, reliability analysis, t-test, ANOVA analysis, multiple regression analysis, correlation analysis and frequency analysis through SPSS 12.0 program. Findings of analyses indicated that items of lifestyle involve d 4 factors, and the item of eating out behaviors was extracted to be 1 factor. As a result of testing differences in lifestyle depending on residential areas, both type of chasing fashion and type of extroverted dependence have significant differences in variables, and both factors indicated that females living in Ulsan have higher mean values than those of females living in Gyeongnam. As a result of analyzing lifestyle depending on age, which was adopted in part, females at the ages of 31~40 had higher mean values than those in other ages in the type of chasing fashion, and females above the age of 51 had higher mean values than those in other ages in type of chasing health. As a result of lifestyle depending on academic backgrounds, university students or graduates had higher mean values than those in other academic backgrounds. For the influence of lifestyle types on eating-out behaviors depending on eating-out motivation, the type of chasing fashion, the type of purchasing the quality of life, and the type of chasing health were p<0.001, having significant effects.

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Association of Cigarette Prices with the Prevalence of Smoking in Korean University Students: Analysis of Effects of the Tobacco Control Policy

  • Han, Jin-Ok;Im, Jeong-Soo;Yim, Jun;Choi, Yoon-Hyeong;Ko, Kwang-Pil;Kim, Junghoon;Kim, Hee Gerl;Noh, Yunhong;Lim, Young-Khi;Oh, Dae-Kyu
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.13
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    • pp.5531-5536
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    • 2015
  • Background: Increased pricing of cigarettes might be one of the most effective approaches for reducing the prevalence of smoking. This study aimed to investigate the effects of increasing cigarette prices through taxation by a tobacco intervention policy on the changes in smoking prevalence in Korean university students. Materials and Methods: The participants in this study were 23,047 healthy university students aged 18-29 years from a health examination in 2011-2015. We investigated the adjusted prevalence of daily and occasional smoking before and after increasing cigarette prices through taxation. Results: The prevalence of occasional smoking was significantly decreased in 2015 from 2014 in both male (from 10.7% in 2014 to 5.4%) and female (from 3.6% to 1.1%) students, but the prevalence of daily smoking did not decrease significantly. The frequency of individuals who had attempted smoking cessation during the past year was significantly higher among occasional smokers in male students (90.2%) compared with daily smokers (64.9%). For female students, there were no differences in experience of smoking cessation, willingness for smoking cessation, or E-cigarette experience between daily and occasional smokers. Conclusions: We found that a policy of increasing cigarette prices through taxation is associated with decreases in the prevalence of occasional smokers, who have relatively lower nicotine dependence compared with individuals who smoke daily. The results of our study suggest that social support and direct intervention for smoking cessation at the community level are needed for university students alongside the pricing policy.