• Journal of Chest Surgery
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• v.13 no.4
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• pp.321-337
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• 1980

The increasing use of cardioplegic solution for the reduction of ischemic tissue injury requires that all cardiplegic solution be carefully assessed for any protective or damaging properties. This study describes functional, enzymatic and structural assessment of the efficiency of three cardioplegic solutions (Young & GIK, Bretschneider, and $K^{+}$ Albumin solution) in a Modified Isolated Rat Heart Model of cardiopulmonary bypass and ischemic arrest. Isolated rat heart were subjected to a 2-minute period of coronary infusion with a cold cardioplegic or a noncardioplegic solution immediately before and also at the midpoint of a 60-minute period of hypothermic ($10{\pm}1$. C) ischemic cardiac arrest. The results of this study were as follow: 1. Spontaneous heart beat after ischemic arrest occured 16 seconds later after Langendorff reperfusion in the Young & GIK group (n=6), and 40 second later in the Bretschneider group (n=6) and 6 minute later in the $K^{+}$ Albumin group (n=6), and 16 minute later in the control group (non-cardioplegia). A good recovery state of spontaneous heart beat was shown in the Young & GIK and Bretschneider groups. 2. The percentage of recorveries of heart function at 30 minute after postischemic working heart perfusion were : heart rate $91.6{\pm}3.1$% (P<0.01)m oeaj airtuc oressyre $83{\pm}3$% (P<0.01), coronary flow $70{\pm}8$% (P<0.05) and aortic flow flow rate $39{\pm}9.3$% (P<0.05) in the Young & GIK group. This percentage of recoveries of the Young & GIK group was significantly greater than the control group. In the Bretschneider group, the percentage of recoveries were : heart rate $87.8{\pm}7.5$%(P<0.05), peak aortic pressure $71{\pm}2.3$% (P<0.05) and aortic flow rate $33.2{\pm}6.6$%(P<0.05). hte percentage of recoveries were significantly greater than in the control group. In the $K^{+}$ Albumin group, recoveries of heart function were poor. 3. Total CPK leakage was $131.2{\pm}12.75$IU/30 min/gm. dry weight in the control group, $50.65{\pm}12.75$IU in the Young & GIK gruop, $69.40{\pm}32.21$Iu in Bretschneider group, and $103.65{\pm}15.47$IU in the $K^{+}$ Albumin group during the 30 minute postischemic Langendorff reperfusion. Total CPK leakage was significantly less (P<0.001) in the Young & GIK group, than in the control group. 4. Direct correlatin between percentage recovery of aortic flow rate and total amount of CPK leakage from Myocardium was noticed.(Correlation Coefficient r = 0.76, P<0.001). 5. Mild perivascular edema was the only finding of light microscopic study of myocardium after 60 minute ischemic arrest with cold cardioplegic solutions and hypothermla.

• Publications of The Korean Astronomical Society
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• v.27 no.4
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• pp.297-298
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• 2012

ANIR (Atacama Near InfraRed camera) is a near infrared camera for the University of Tokyo Atacama 1m telescope, installed at the summit of Co. Chajnantor (5,640 m altitude) in northern Chile. The high altitude and extremely low water vapor (PWV = 0.5 mm) of the site enable us to perform observation of hydrogen $Pa{\alpha}$ emission line at $1.8751{\mu}m$. Since its first light observation in June 2009, we have been carrying out a $Pa{\alpha}$ narrow-band imaging survey of nearby luminous infrared galaxies (LIRGs), and have obtained $Pa{\alpha}$ for 38 nearby LIRGs listed in AKARI/FIS-PSC at the velocity of recession between 2,800 km/s and 8,100 km/s. LIRGs are affected by a large amount of dust extinction ($A_V$~ 3 mag), produced by their active star formation activities. Because $Pa{\alpha}$ is the strongest hydrogen recombination line in the infrared wavelength ranges, it is a good and direct tracer of dust-enshrouded star forming regions, and enables us to probe the star formation activities in LIRGs. We find that LIRGs have two star-forming modes. The origin of the two modes probably come from differences between merging stage and/or star-forming process.

• Journal of the Korean Society for Nondestructive Testing
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• v.36 no.4
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• pp.281-287
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• 2016

Fiber Bragg grating (FBG) sensors are applied in structural health monitoring (SHM) in various application fields because of their ease of multiplexing and capability of performing absolute measurements. Moreover, the packaging methods of FBG sensors accelerate their commercialization rapidly. However, long-term SHM exposes the FBG sensors to cyclic thermal loads, and a investigation is required because it finally leads to the signal instability of the FBG sensors. In this study, the effects of sensor packaging methods two methods are generally used for the FBGs: (bonding both sides of the FBG or bonding the FBG directly on signal stability of FBG sensors are investigated. Tests are conducted on specimens in a thermal chamber, over a temperature range from $-20^{\circ}C$ to $60^{\circ}C$ for 300 cycles. Signal characteristics such as Bragg wavelength, light intensity and full width at half maximum are examined and are compared with those of the FBG sensors, obtained in a previous study under direct bonding conditions. From the comparison, it is observed that the FBG sensors with bonding on both sides of the FBG demonstrate higher signal stabilities when exposed to cyclic thermal loads during long-term SHM. Consequently, it guarantees more effectiveness when packaging the FBG sensors.

• The Research Journal of the Costume Culture
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• v.8 no.3
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• pp.387-410
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• 2000

The purpose of this study was to approach to the internal meanings included in the Happening and the culture of hippies, by analysing the basic mental conditions in the process of the Happening. And this study was composed of the concept and the development of Happening, the characteristics of the hippies that related in the midst of the happening's background, and the formativeness between these factors and hippies'fashion. Since the happening a genre of fine arts expression attended the New School for social research in New York in 1954, Allan Kaprow direct-influenced by John Cage used the word 'Hapening'first, practicing '18 Happenings in 6 parts'at the Rueben gallery in 1959. Kaprow's 18 Happenings was one of the earliest opportunities for a wider public to attend the live events that several artists had performed more privately for various friends. Despite the very different sensibilities and structures of artist's works, artists were all thrown together by the press under the general heading of 'Happening', following Kaprow's 18 Happenings. Being considered as the root of the Happening 'Expression of Sound'of John Cage was the discovery of the exisiting thing- the Happening. Most artists were to be deeply influenced by Cage's theories and attitudes-that is, his sympathy for Zen Buddihism and oriental philosophy-and by reports of the Black Mountain events. These events would directly reflect contemporary painting and stemmed from the Futurists, Dadaists and Surrealists. And Happening's development background was based on the culture of hippies. Swinging London had been under the sway of psychedelic drugs and utopian visions of 'hippie'wave sweeping in from Califonia. This wave, which affected solid middle-class youth first and formost, began in Haight Ashbury in San Francisco. Without dwelling on the hippie movement here, it is worth nothing that it resulted from the convergence of several undercurrents : consciousness-expending drugs, the anti-Vietnam war developments, the impact of English pop groups on American music and the rise of protest songs, and finally the beatnik tradition of non-conformism. Hippie culture and its pursuit of love, peace and psychedelia was the antitheses of 1960s main street fashion. The media gave everyone with long hair the label of 'hippie', but it was always a very loose collage of attitudes and styles. The rejection of sexual taboos was conveyed by the hippie's refusal to wear. Although the bold exposure of body raised controversies because it went against the existing moral values, it has a significant implications. Psychedelics brought mind-expansion and the possibillity that modern technology (light show, synthesized electronic sounds), new fabrics or colors, and LSD could be utilized to provide an escape route from the dreariness of modern life. During the 1960s, traditional costumes, many of which had never been seen outside their native regions, became sought after and adopted in the West, initially by the young, who wanted to demonstrate their solidarity with cultures uncontaminated by mass industry. The most ardent proponents of such folk costumes were the hippies. Hippies dress was sometimes decribed as 'anti-fashion', produced by a patchwork of ragged cast-offs and flamboyant accessories, of outmoded Western dress and time-honored ethnic garments all combined, modified and permutated into variety of personal statements. 'Flower Power'became a reality. From the results of this study, we can see the expanding trend of the influence and the concept of the sew art genre 'Happening'in the formativeness as well as the fine arts field.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.1
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• pp.27-40
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• 1997

This study investigated the effects of laser irradiation on the exposed pulp and the possibility of direct pulp capping with the $CO_2$ laser. Results were obtained from the observation of the residual pulpal healing process. Class V cavities on 48 anterior teeth from 8 adult dogs were prepared and pulp chambers were intentionally opened with dental explorer. The control group consisted of 16 teeth. $Dycal^{(R)}$(Caulk Co., U.S.A.) was applied to exposed site once bleeding was stopped. Cavities were sealed with $I.R.M^{(R)}$. In the experimental group 1 (16 teeth), laser(LASERSAT $CO_2^{(R)}$, Satelec Co.) was irradiated on the exposed pulp. The laser procedure followed the manufacturers recommendations for the treatment of human pulp(1.5 Watts, 0.2 seconds, unfocused), and cavities were sealed with $I.R.M^{(R)}$. In the experimental group 2 (16 teeth), laser was irradiated on the exposed pulp in a more powerful dosage(5.0 Watts, 0.2 seconds, unfocused), and cavities were sealed with $I.R.M^{(R)}$. Two dogs were sacrificed immediately after experiment and the others were sacrificed at intervals of one, three, and eight weeks respectively. All teeth were routinely processed and the pulpal tissues and odontoblastic layers were observed by the light microscope. The results were as follows; 1. In the control group, the initial mild inflammation had improved to normal by week eight. An active formation of reparative dentin was observed at week three, and at week eight, a firm dentin bridge was present beneath the $Dycal^{(R)}$ with no inflammatory responses in the remaining pulp. 2. In the experimental group 1, immediately following irradiation, the superficial shape of the exposed pulp was crater-like. And it was lined with the coagulated layer, $60{\sim}70{\mu}m$ in width. Moderate inflammatory pulpal conditions existing at week one were improved to mild at week eight. And from the week three specimens, a reparative dentin formation was observed in the adjacent odontoblastic layer of the exposed site. A dentin bridge at the exposed site, however, did not form during the experimental period. 3. In the experimental group 2, the width of the coagulation layer lining the crater was $70{\sim}130{\mu}m$. Beneath the coagulated layer, severe inflammatory pulpal responses were observed at week one, and conditions did not improve during the experimental period.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.12
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• pp.1939-1949
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• 2008

The purpose of this study was to identify differences or similarities across the ensembles of 2006 F/W fashion trends in the big fashion centers such as Paris, London, New York, and Seoul, by street fashion research. The study focuses on understanding of localized fashion trend in the marketplace. We used photograph observation and analyzed data by SPSS program. We found there is a significant difference in winter outfits at these different global fashion mega cities. Most Korean women were wearing light colored outer jackets and blue jeans were dominant style for pants. The majority of Paris/London, New York and Seoul people on the street were wearing wool/wool like coat. Padded coats were worn more by New Yorkers than by people in Seoul. For the bottom, there is a similarity between Paris/London, and New York City, in that skinny pants were popular. Koreans were wearing skinny pants mostly, but the percentage of mini skirts/shorts was also higher than any other cities. We found that the cross-cultural fashion mega trend is similar in clusters, but there is a slight difference of trend in clothing color, style and design details, and accessories by localized fashion cities. Not only direct observation but also identification of cultural characteristics and consumer behavior through the years will bring much more contributions to apparel industries.

• Restorative Dentistry and Endodontics
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• v.21 no.1
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• pp.19-34
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• 1996

It has been demonstrated that intracoronal bleaching of pulpless teeth may result in cervical root resorption. Several authors postulated that bleaching agents such as hydrogen peroxide penetrated through the dentinal tubules to damage the surrounding tissues that cause cervical root resorption. The purpose of this study was to suggest on in vitro model for direct determination of hydrogen peroxide penetration through CEJ during nonvital bleaching. In addition, this model permit the quantification of the amount of hydrogen peroxide penetrated during the procedure. Freshly extracted intact premolars, removed for orthodontic reasons were used. Root canal treatment was performed in each tooth. And then the outer surface and crown portion of the teeth was sealed with wax leaving the CEJ. The prepared teeth mounted on the wax laminates were placed in plastic assay tubes containing 1.5ml bidistilled water with their entire root, including the CEJ, submerged in the solution. The teeth were dividied into four groups. Thermo group : thermocatalytic bleaching with superoxol Walk group: walking bleaching with sodium perborate & superoxol Combi group : combination of thermocatalytic & walking bleaching Dw group : walking bleaching with sodium perborate & water The bleaching procedure was performed three times. The bleaching intervals were at 3 days. The hydrogen peroxide present in the assay system was added to ferrous ammonium sulfate resulting in ferric ion release. Upon the addition of potassium thiocyanate a ferrithiocyanate complex results, which absorbs light at the wavelength of 467nm. The radicular penetration of hydrogen peroxide in the four groups was assessed directly using spectrophotometer. The amount of hydrogen peroxide in the samples tested is determined by comparing them with a standard curve generated by known amounts of hydrogen peroxide. The results were obtained as follows : 1. In all experimental groups except the Dw group showed lower penetration amount in day 4 than day 1, there was statistical importance in the difference (P<0.05). 2. After 3rd treatment, Thermo group showed slightly increased value and narrow distribution. Walk group showed much more penetration amount and widely dispersed value. Value of Combi group showed wide distribution without regard to treatment time, but value of Dw group evenly distributed. 3. Thermo group, Walk group and Dw group showed a tendency of increasing penetration amount with increasing treatment times(P<0.01), but Combi group revealed no statistically important differences. 4. Combi group showed the highest degree of penetration. Walk group showed lower penetration than Combi group. Thermo group & Dw group showed lower than Walk group. 5. Cervical root permeability to hydrogen peroxide varied from 0 to 35 %.

• Resources Recycling
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• v.20 no.1
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• pp.54-60
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• 2011

The spherical artificial aggregates (AAs) with a diameter of 8 mm, which contains fly ashes discharged from the fluidized bed combustion in a thermal power plant and clay were manufactured by direct sintering method at $1050{\sim}1250^{\circ}C$ for 10 minutes. The effect of fly ash contents on the bloating phenomenon in the AAs was analyzed. The AAs containing fly ash of the amount under 50 wt% showed the black-coring and bloating phenomena. The AAs containing fly ash of the amount over 5Owt%, however, the specific gravity was increased and the color of specimens fully changed to black. These color change phenomena were caused from the formation of FeO by the reduction reaction of almost $Fe_2O_3$ component by the excessive reducing atmosphere formed simultaneously with the rapid emission of the gases generated from the high contents of unburned carbon of with increasing the added fly ash amount. Specific gravity was decreased as fly ash contents increased in the case of sintering at the same temperature condition. Water absorption of all specimens except of the specimens containing 10 wt% fly ashes decreased with increasing sintering temperature. These were because a liquid phase was formed as the increasing the sintering temperature. In the case of the specimens manufactured in this study containing fly ashes discharged from the fluidized bed combustor in a the thermal power plant and 10~90 wt% of clay, the specific gravity was 0.9~1.8 and the water absorptivity was 8~60%, therefore it is considered that those results can be applied to the light or heavy aggregates.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.345-346
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• 2013

InGaN material is being studied increasingly as a prospective material for solar cells. One of the merits for solar cell applications is that the band gap energy can be engineered from 0.7 eV for InN to 3.4 eV for GaN by varying of indium composition, which covers almost of solar spectrum from UV to IR. It is essential for better cell efficiency to improve not only the crystalline quality of the epitaxial layers but also fabrication of the solar cells. Fabrication includes transparent top electrodes and surface texturing which will improve the carrier extraction. Surface texturing is one of the most employed methods to enhance the extraction efficiency in LED fabrication and can be formed on a p-GaN surface, on an N-face of GaN, and even on an indium tin oxide (ITO) layer. Surface texturing method has also been adopted in InGaN-based solar cells and proved to enhance the efficiency. Since the texturing by direct etching of p-GaN, however, was known to induce the damage and result in degraded electrical properties, texturing has been studied widely on ITO layers. However, it is important to optimize the ITO thickness in Solar Cells applications since the reflectance is fluctuated by ITO thickness variation resulting in reduced light extraction at target wavelength. ITO texturing made by wet etching or dry etching was also revealed to increased series resistance in ITO film. In this work, we report a new way of texturing by deposition of thickness-optimized ITO films on ITO nano dots, which can further reduce the reflectance as well as electrical degradation originated from the ITO etching process.

• The Journal of the Korea Contents Association
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• v.17 no.3
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• pp.654-665
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• 2017

It is major strategy for SMEs to cooperate with other companies or Public Research Institutes(PRIs) as the essential technology is getting more complicated and technological life cycle is getting short. However, It is not easy to perform a proper cooperation with SMEs for PRIs, because they are accustomed to support SMEs in the short run. In addition, previous studies also have mainly focussed on finding determinants of performance as a consequence of temporary cooperation instead of long-term relationships among companies. Therefore this study analyzed which satisfaction is more effective to maintain the long-term cooperative relationship between PRIs and SMEs. As a result, it has found that when SMEs satisfy from quality of input like manpower supports R&D and context of the support program over the output like technological or economical performance, they intend to continue cooperation with PRIs. And this paper shows that the performance has mediated effect rather direct effect on long-term cooperation intention. In light of all the above, to cooperate with SMEs effectively, it will be suggested that PRIs enhance quality of support process and contents instead of quantity of support based on one-time cooperation.