• Bulletin of the Korean Chemical Society
• /
• v.20 no.8
• /
• pp.905-909
• /
• 1999

Reaction of tetrahomodioxa p-phenylcalix[4]arene with ethyl bromoacetate and potassium carbonate in ace-tone leads to the title tetra ester derivative, 7,13,21,27-tetra-phenyl-29,30,31,32 -tetrakis(ethoxycarbonyl)meth-oxy-2,3,16,17-tetrahomo-3,17-dioxacalix[4]arene, its structure was determined by NMR spectra as 1,4-alternate conformation. The molecular structure has been solved by X-ray diffraction methods. The molecule has a conformation with pseudo center of symmetry. The benzene ring A is up, ring C is down, B and D rings are flat with respect to the plane of the macrocyclic ring.

• Bulletin of the Korean Chemical Society
• /
• v.20 no.5
• /
• pp.531-534
• /
• 1999

Irradiation (300 nm UV light) of dibenzoylmethane and 1,4-naphthoquinone in dichloromethane gave 1,5-dike-tone as the major product, along with β-hydroxyketone as the minor product. Anthraquinone and anthrone also added photochemically to dibenzoylmethane to give 1,5-diketones as the major products. In contrast, tetrahalo-1,4-benzoquinones added to dibenzoylmethane to give two types of 1,5-diketones via oxetane and cyclobutane intermediates. Comparison of the potential energy values of the photoproducts reveals that the 1,5-diketones are more stable than the corresponding oxetanes or cyclobutanes due to the ring-strain of the bicyclic compounds.

• Proceedings of the IEEK Conference
• /
• 2008.06a
• /
• pp.879-880
• /
• 2008

Music can give pleasure to people according to a rhythm, and Musical instrument can make various sounds according to quality of the lumber. A string instrument makes sound by strings so it feels very soft and a brass makes to feel a high pitched tone. A gayageum makes sound by oscillation which is transferred to a resonator when a string is touched. And this sound is very soft and faint. Therefore, in this paper, we researched sound properties of gayageum according to quality of the lumber of musical instrument. As the result of researches, we found that melody is affected by the annual ring of the resonance lumber.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2010.10a
• /
• pp.757-758
• /
• 2010

At the time of medical treatment and surgical operation, halogen lamp and plasma lamp were mainly used as luminous source for lighting. These two luminous sources have drawbacks that the life of lamps are not long, various problems are brought about due to excessive heat generation and its volume is very big because of cooling device. Accordingly, in this research a ring light was developed so that a partial shadowless shooting for the patient's affected area at the medical treatment room and surgical operation room using high luminance LED for which attention is being paid as new lighting parts for medical purpose. LED which was applied to the development used high luminance three color LED for full color for which various color materialization and the adjustment of radiation intensity are possible and we can get white light in order to emphasize the delicate expression for generic tone of shooting object, strong highlight, simple shadow and three dimensional effect at the time of close-up shadowless shooting of the affected area.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.23 no.9
• /
• pp.708-713
• /
• 2010

In this research a ring light was developed so that a partial shadowless shooting for the patient's affected area at the medical treatment room and surgical operation room using high luminance light emitting diode (LED) for which attention is being paid as new lighting parts for medical purpose. LED which was applied to the development used high luminance three color LED for full color for which various color materialization and the adjustment of radiation intensity are possible and we can get white light in order to emphasize the delicate expression for generic tone of shooting object, strong highlight, simple shadow and three dimensional effect at the time of close-up shadowless shooting of the affected area. And at the time of design of ring light, the characteristics of LED and the loss of light at the time of penetrating light diffusion PC were considered so that intensity of illumination for over 150 lx can be obtained. The result of measurement of the intensity of illumination of the ring light that was developed revealed that maximum intensity of illumination of 225.7 lx was obtained, while smoke index was measured to be maximum 78 Ra in the case of Red(50%) Green(100%) and Blue LED(60%). We could confirm that response speed was also very fast as 1.72 ms.

• Science of Emotion and Sensibility
• /
• v.11 no.3
• /
• pp.313-324
• /
• 2008

The purpose of the study is to investigate the influence of Ring-Back-Tone(RBT) music on the evaluation of the phone-call receiver's personality in dimensions of Openness, Extroversion, and Neuroticism. In a preliminary test, the subjects listened to 17 RBT music stimuli in random order and assessed the personality associated with liking for each music(N=15). Among the 17 RBTs, three were selected to be used in Experiments I and II and they were distinguished from each other in terms of the three personality dimensions(p<0.001). In Experiment I, the subjects were divided into four groups and were asked to make a call to interview an unknown receiver(N=60). Different RBT music was installed depending on the group to which each subject belonged. It was found that different RBT influences the caller's evaluation of the receiver's personality, supporting Hypothesis 1(p<0.001). Moreover, the ratings of the receiver's were highly correlated with those of the RBT music stimuli in terms of Openness(r=0.722, p<0.001) and Extroversion(r=0.753, p<0.001). In Experiment II, an identical experiment design was applied for a new group of subjects who were acquainted with the receiver(N=40). It was hypothesized that previous knowledge about a person would weaken the RBT effect. The results showed that RBT exerted no effect on the evaluation of the receiver's personality when the caller knew the receiver. It was also found that 12 personality traits, where each of the three personality dimensions is described by four traits, facilitated assessment of the character of the RBT music as well as the personality of the receiver.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
• /
• 2002.05a
• /
• pp.137-137
• /
• 2002

Several epidemiologidal studies suggested that arsenic exposure was strongly correlated with the development of cardiovascular disease such as hypertension. In order to examine whether arsenic affects vasomotor tone in blood vessels, we investigated the effect of arsenic on agonist-induced vasorelaxation using the isolated rat aortic ring in in vitro organ bath system. Treatment with arsenite inhibited acetylcholine-induced relaxation of aortic rings in a concentration- dependent manner. The inhibitory effects by arsenic were also observed in the relaxation induced by sodium nitroprusside, a NO-donor. Consistent with these findings, the cGMP levels stimulated by acetylcholine in blood vessels were reduced significantly by arsenite treatment. In addition, higher concentration of arsenite decreased the relaxation by 8-Br-cGMP, a cGMP analog, in aortic rings without endothelium. These in vitro results indicated that arsenite that arsenite was capable of suppressing acetylcholine-induced relaxation in blood vessels by inhibiting production of nitric oxide in endothelial cells and by impairing the relaxation machinary in smooth muscle cells. In vivo studies revealed that the reduction of blood pressure by acetylcholine infusion was signigicantly suppressed after arsenite was administered intravenously to rate. These data suggest that vasomotor tone impaired by arsenite exposure may be one of the contrbuting factors in development of cardiovascular disease.

• The Korean Journal of Physiology
• /
• v.30 no.1
• /
• pp.11-20
• /
• 1996

To investigate the properties of cromakalim-opened $K^{+}\;channels$ in aorta of spontaneously hypertensive rats (SHR), the effect of cromakalim on tension was compared in endothelium-rubbed aortic rings from SHR and normotensive Wistar-Kyoto rats (WKY). 1. Cromakalim relaxed the aortic ring contracted by $10^{-7}$ M norepinephrine (NE) dose-dependently, and this relaxant response to cromakalim was blocked by $10^{-5}$ M glybenclamide. 2. Cromakalim also relaxed the contraction induced by high $K^{+}$-solution or 10 mM tetraethylammonium dose-dependently. However, the relaxant response to cromakalim was decreased by raising the $K^{+}$ concentration. 3. SHR aorta exhibited myogenic tone in resting state which was inhibited by cromakalim, verapamil or $Ca^{2+}-free\;PSS.$ Whereas, WKY aorta did not exhibit any myogenic tone in resting state. 4. When aortic rings from both strains were contracted by $20\;mM\;K^{+}\;or\;NE$, relaxant responses to low concentration of cromakalim $(below\;10^{-7}\;M)$ were not different between WKY and SHR, but maximum relaxant response to cromakalim $(above\;3{\times}10^{-7} \;M)$ was greater in SHR than in WKY. 5. When the relaxant response to cromakalim was expressed as percent of maximum relaxation induced by $Ca^{2+}-free\;PSS$, relaxant response to cromakalim in 20 mM $K^{+}-induced$ contraction was not different between WKY and SHR. From the above result, it is suggested that relaxant responses to cromakalim are greater in SHR than WKY, and this may be due to the myogenic tone of aortic rings from SHR.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2005.11a
• /
• pp.957-960
• /
• 2005

최근 무선 인터넷이 가능하고 엄청난 성능을 발휘하는 핸드폰의 보급으로 인해 이제는 다양한 모바일 콘텐츠가 필요로 되고 있다. 그래서 통신사는 게임, 음악, GPS 등을 이용한 많은 콘텐츠를 개발하여 유료로 공급하고 있다. 하지만 요즘 사용자들은 여러 해킹 툴을 사용하여 유료 콘텐츠를 무단으로 배포하므로 콘텐츠 개발업체와 이동통신사에 손해를 입히고 있다. 본 논문에서는 콘텐츠 중 가장 많이 사용되고 있는 벨소리를 보호하는 기법을 제시하여 안전한 모바일 DRM 시스템이 갖추어지기 전 단계에서 그로 인한 피해를 효과적으로 줄이는 것을 기대할 수 있다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2005.11a
• /
• pp.969-972
• /
• 2005

최근 무선 인터넷이 가능하고 엄청난 성능을 발휘하는 핸드폰의 보급으로 인해 이제는 다양한 모바일 콘텐츠가 필요로 되고 있다. 그래서 통신사는 게임, 음악, GPS 등을 이용한 많은 콘텐츠를 개발하여 유료로 공급하고 있다. 하지만 요즘 사용자들은 여러 해킹 툴을 사용하여 유료 콘텐츠를 무단으로 배포하므로 콘텐츠 개발업체와 이동통신사에 손해를 입히고 있다. 본 논문에서는 콘텐츠 중 가장 많이 사용되고 있는 벨소리를 보호하는 기법을 제시하여 안전한 모바일 DRM 시스템이 갖추어지기 전 단계에서 그로 인한 피해를 효과적으로 줄이는 것을 기대할 수 있다.