• Title/Summary/Keyword: $R_1$-space

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AN EFFECT OF HYALURONIC ACID ON THE TEMPOROMANDIBULAR JOINT ARTHROCENTESIS (악관절강내 천자술시 히알루산(Hyaluronic acid) 사용에 대한 임상적 연구)

  • Yeo, Hwan-Ho;Kwon, Byong-Gon;Kim, Jae-Seung
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.21 no.4
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    • pp.388-394
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    • 1999
  • To compare the effect of hyaluronate and dexamethasone on the temporomandibular joint arthrocentesis the author investigated 22 temporomandibular joint disorder(TMD) patients with pain and limitation of mouth opening who visited at the Department of Oral and Maxillofacial Surgery. Chosun Dental Hospital and were made a diagnosis as Wilkes stage III or IV of TMJ internal derangement clinically and radiographically. The two groups consisted of 10 patients with injection of sodium hyaluronate 10mg$(Artz^{(R)})$(hyaluronate group) on the upper joint space of the affected temporomandibular joint 5 times at intervals of a week after arthrocentesis, and 12 patients with injection of dexamethasone$(Oradexon^{(R)})$ at a time(dexamethasone group). Maximum mouth opening, pain value and satisfaction value during mastication were assessed on a visual analog scale before arthrocentesis and after 6 months. Then the within-group and between-group differences were evaluated in the obtained data and the clinical success rate of each group was calculated according to our success criteria. The results were as follows. 1. the mean of maximum mouth opening before arthrocentesis and after 6 months in the hyaluronate group were 24.9mm and 39.0mm respectively, and those before arthrocentesis and after 6 months in the dexamethasone group were 25.7mm and 41.3mm respectively. 2. The mean of pain value on a visual analog scale in the hyaluronate group before arthrocentesis and after 6 months were 6.7 and 1.8 respectively, and those in the dexamethasone group before arthrocentesis and after 6 months were 7.0 and 1.8 respectively. 3. The mean of satisfaction value during mastication on a visual analog scale in the hyaluronate group before arthrocentesis and after 6 months were 2.8 and 7.7 respectively, and those in the dexamethasone group before arthrocentesis and after 6 months were 3.1 and 7.8 respectively. 4. There were statistically significant differences between all measurements before arthrocentesis and after 6 months(P<0.001), but no difference between all measurements in the hyaluronate group and those in the dexamethasone group. 5. The over all success rate of the hyaluronate group and the dexamethasone group were 60.0% and 63.6% respectively. In summary, there was significant difference between the effect of hyaluronate and dexamethasone on the temporomandibular joint arthrocentesis but hyaluronate is better than corticosteroid as the injection drug in consideration of the side effect related with repeated injection.

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Enhanced SBAS Integration Method Using Combination of Multiple SBAS Corrections

  • Yun, Ho;Kim, Do-Yoon;Jeon, Sang-Hoon;Park, Bynng-Woon;Kee, Chang-Don
    • International Journal of Aeronautical and Space Sciences
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    • v.10 no.1
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    • pp.75-82
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    • 2009
  • In this parer, we propose a new way of improving DGNSS service using combination of multiple SBAS information. Because SBAS uses Geostationary Earth Orbit (GEO) satellites, it has very large coverage but it can be unavailable in urban canyon because of visibility problem. R. Chen solved this problem by creating Virtual Reference Stations (VRS) using the SBAS signal [1]. VRS converts SBAS signal to RTCM signals corresponding its location, and broadcast the converted RTCM signals over the wireless internet. This method can solve the visibility problem cost effectively. Furthermore it can solve DGNSS coverage problem by creating just a transmitter instead of a reference station. Developing above method, this paper proposes the methods that integrate two or more SEAS signals into one RTCM signal and broadcast it. In Korea, MSAS signal is available even though it is not officially certified for Korean users. As a Korean own SBAS-like system, there is the internet-based KWTB (Korean WADGPS Test Bed) which we developed and released at ION GNSS 2006. As a result, virtually two different SBAS corrections are available in Korea. In this paper, we propose the integration methods for these two independent SBAS corrections and present the test results using the actual measurements from the two systems. We present the detailed algorithm for these two methods and analyze the features and performances of them. To verify the proposed methods, we conduct the experiment using the logged SBAS corrections from the two systems and the RINEX data logged at Dokdo monitoring station in Korea. The preliminary test results showed the improved performance compared to the results from two independent systems, which shows the potential of our proposed methods. In the future, the newly developed SBASs will be available and the places which can access the multiple SBAS signals will increase. At that time, the integration or combination methods of two or more SBASs will become more important. Our proposed methods can be one of the useful solutions for that. As an additional research, we need to extend this research to the system level integration such as the concept of the decentralized W ADGPS.

Monitoring Urban Ecological corridors in Gwanggyo New Town Using Camera Trapping (카메라트래핑을 활용한 광교신도시 내 도시형 생태통로 모니터링)

  • Park, Il-Su;Kim, Whee-Moon;Kim, Seoung-Yeal;Park, Chan;Song, Won-Kyong
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.24 no.1
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    • pp.69-80
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    • 2021
  • The new town in Korea, developed as a large-scale housing plan, has created urban ecological corridors to provide habitat and movement routes to wildlife and to promote natural ecological flow. This study aimed to investigate the use of wildlife in 10 ecological corridors in Gwanggyo New Town through camera trap technology and confirm effectiveness by identifying environmental factors affecting the use of wildlife's urban ecological corridors. Our researchers installed 20 unmanned sensor cameras at each the entrance and exit of the ecological corridors, and monitored urban wildlife for 10 weeks. According to the monioring results, the main species in Gwanggyo New Town were identified not only raccons, cats, water deer, korean hare and avain but also magpies, dove, eurasian tree sparrow, ring-necked pheasant, and eurasian jay. The number of uses ecological corridors of urban residents was 801(13.49%), as high as that of urban wildlife (1,140, 19.20%), which was judged to have disturbed the use of ecological corridors by wildlife. However, most dominant species of urban wildlife are nocturnal so that, it was judged that they share home range with urban residents at a time interval. In addition, according to the correlation analysis results between the mammal using rate of the urban ecological corridors and environmental factors(ecological corridor-specific length, ecological corridor-specific width, cover degree, shielding degree, connected green area, separation of movement routes, and presence of streetlights), environmental factors were not statistically significant. However, the more the area of green space connected to ecological corridors, the more increasing the mammal using rate of ecological corridor(r=0.71, p<0.05). Therefore, the area of green space connected to the ecological corridors that is associated with rate of wildlife using corridors should be considered as a priority when developing an urban ecological corridors. In the future, this study will extend the observation period of the ecological corridors and continuously accumulate data by adding the number of observation cameras. Furthermore, it is expected that the results of this study can be used as basic data for the standards for urban ecological corridors installation.

Recent research activities on hybrid rocket in Japan

  • Harunori, Nagata
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2011.04a
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    • pp.1-2
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    • 2011
  • Hybrid rockets have lately attracted attention as a strong candidate of small, low cost, safe and reliable launch vehicles. A significant topic is that the first commercially sponsored space ship, SpaceShipOne vehicle chose a hybrid rocket. The main factors for the choice were safety of operation, system cost, quick turnaround, and thrust termination. In Japan, five universities including Hokkaido University and three private companies organized "Hybrid Rocket Research Group" from 1998 to 2002. Their main purpose was to downsize the cost and scale of rocket experiments. In 2002, UNISEC (University Space Engineering Consortium) and HASTIC (Hokkaido Aerospace Science and Technology Incubation Center) took over the educational and R&D rocket activities respectively and the research group dissolved. In 2008, JAXA/ISAS and eleven universities formed "Hybrid Rocket Research Working Group" as a subcommittee of the Steering Committee for Space Engineering in ISAS. Their goal is to demonstrate technical feasibility of lowcost and high frequency launches of nano/micro satellites into sun-synchronous orbits. Hybrid rockets use a combination of solid and liquid propellants. Usually the fuel is in a solid phase. A serious problem of hybrid rockets is the low regression rate of the solid fuel. In single port hybrids the low regression rate below 1 mm/s causes large L/D exceeding a hundred and small fuel loading ratio falling below 0.3. Multi-port hybrids are a typical solution to solve this problem. However, this solution is not the mainstream in Japan. Another approach is to use high regression rate fuels. For example, a fuel regression rate of 4 mm/s decreases L/D to around 10 and increases the loading ratio to around 0.75. Liquefying fuels such as paraffins are strong candidates for high regression fuels and subject of active research in Japan too. Nakagawa et al. in Tokai University employed EVA (Ethylene Vinyl Acetate) to modify viscosity of paraffin based fuels and investigated the effect of viscosity on regression rates. Wada et al. in Akita University employed LTP (Low melting ThermoPlastic) as another candidate of liquefying fuels and demonstrated high regression rates comparable to paraffin fuels. Hori et al. in JAXA/ISAS employed glycidylazide-poly(ethylene glycol) (GAP-PEG) copolymers as high regression rate fuels and modified the combustion characteristics by changing the PEG mixing ratio. Regression rate improvement by changing internal ballistics is another stream of research. The author proposed a new fuel configuration named "CAMUI" in 1998. CAMUI comes from an abbreviation of "cascaded multistage impinging-jet" meaning the distinctive flow field. A CAMUI type fuel grain consists of several cylindrical fuel blocks with two ports in axial direction. The port alignment shifts 90 degrees with each other to make jets out of ports impinge on the upstream end face of the downstream fuel block, resulting in intense heat transfer to the fuel. Yuasa et al. in Tokyo Metropolitan University employed swirling injection method and improved regression rates more than three times higher. However, regression rate distribution along the axis is not uniform due to the decay of the swirl strength. Aso et al. in Kyushu University employed multi-swirl injection to solve this problem. Combinations of swirling injection and paraffin based fuel have been tried and some results show very high regression rates exceeding ten times of conventional one. High fuel regression rates by new fuel, new internal ballistics, or combination of them require faster fuel-oxidizer mixing to maintain combustion efficiency. Nakagawa et al. succeeded to improve combustion efficiency of a paraffin-based fuel from 77% to 96% by a baffle plate. Another effective approach some researchers are trying is to use an aft-chamber to increase residence time. Better understanding of the new flow fields is necessary to reveal basic mechanisms of regression enhancement. Yuasa et al. visualized the combustion field in a swirling injection type motor. Nakagawa et al. observed boundary layer combustion of wax-based fuels. To understand detailed flow structures in swirling flow type hybrids, Sawada et al. (Tohoku Univ.), Teramoto et al. (Univ. of Tokyo), Shimada et al. (ISAS), and Tsuboi et al. (Kyushu Inst. Tech.) are trying to simulate the flow field numerically. Main challenges are turbulent reaction, stiffness due to low Mach number flow, fuel regression model, and other non-steady phenomena. Oshima et al. in Hokkaido University simulated CAMUI type flow fields and discussed correspondence relation between regression distribution of a burning surface and the vortex structure over the surface.

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A Study of Deconstruction in Clothing -Comparison of Clothing with Architecture- (복식에 나타난 해체주의 양식연구 -건축과 복식의 비교-)

  • 전혜정
    • Journal of the Korean Society of Costume
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    • v.32
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    • pp.293-312
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    • 1997
  • Deconstructionism is a philosophical stream in the latter half of 20'th century which goes against western metaphysics and tries to deconstruct the dualism e.g. eastern/west-ern man/woman. Its main concepts are 'indi-vidual' 'other' 'difference' 'restoration of the repressed' 'decentralization' 'Today it shows strong influences in literature art, and other social fields. This study investigated inner meanings and exterior forms represented in clothing on the base of Jacques Derrida's theory in order to re-search modes of deconstruction in is. And it compared clothing with architecture among other genres of art in order to discover similarities between through and modes of art in a certain period. For illuminating concept of deconstruction I referred to the literatures of preceding studies and for deconstruction's characteristics in both clothing and architec-ture I referred work's collection book $\ulcorner$collec-tions$\lrcorner$ and other related books dealing from 1960's to this point. As a rsult there are four modes of decons-truction in both clothing and architecture as follows; 1) Differenance which is a concept of the dif-ference in time and space as being trace. 2) In termeaning of meanings which is not present in reality but re-interpreted a new in the future. 3) Interxtuality in which a texte is not alone but with others 4) Dis.De phenomenon in which distortion and fragmentation forms occur as the result of the denial of perfection and reson. There are characteristics of modes of de-construction in clothing as follows; 1) Differance; R.Gigli, P. Rabanne. G.Bersace, V.Westwood are representatives of the cloth-ing which is combined with the past the pres-ent and the future or is re-viewed as the clothing of the past in the present point of view. J. Watanabe R. Dawakubo I miyake are representatives of the clothing which is out-date but re-viewed in the sense of recollec-tion and re-usage. 2) Intermeaning of meanings: R. kawakubo I, Miyake Y,Yamamoto are representatives of the clothing which is incomplete but re-interpreted in the future and appears to be new-fashioned according to ways of bnding wearing throwing on and tying J.C. Castel-bajac K.Hamnett S.Sprouse are representa-tives of the clothing which is made up of ab -stract forms scribbling or symbolic letters which appears to be different according to view-point of observers. 3) Intertextuality ;J.P.Gaultier K.Hamnett, Comme des Gar ons are representatives of intertextuality of gender which avoids the 여-ality of man/woman J.P Gaultier G,Versace J. galliano are representatives of the intertex-tuality of time place and occasion which mixes temporality extensity and purposiveness. J.P Gaultier G,Versace are representatives of the intertextuality of coordination which combines items different in image purpose and use. P.Rabanne A,Courr ges R,Gernreic I,Miyake are representatives of the intertextuality of mat-ter which uses heterogeneous matter different from cloth. 4) Dis.De-phenomenon: R, Kawakubo I.Mi-yake J.P.Gaultier are representatives of the de-composition which discloses distortion and exag-geration of form through destructing the estab-lished way of construction J.Galliano R.Kawa-kubo Devota Y Lomba arte representatives of the decentring which restores the repressed and the alienated on the one hane and shows front-centrality on the other. Comme des Gar ones is representative of the discontinuity because of which right and left up and down are not in har-mony with one another. J,Galliano J.P,Gaultier T,Mugler are representatives of the disruption by way of which one makes one's body exposed through intentional slashes or holes. As a consequence deconstructionism enabled us to investigate similarities between through of deconstruction and modes of art interms of diffrance Intermeaning of meanings intertextuality and Dis De-phenomenon. And we found that deconstruction was a phase of development in that it as a all-comprising and multiple concept tries to pursue the new through deconstruction.

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Objective in Vivo Quantification of Emphysema by Thin-Section CT: Correlation with Physiologic Findings (고해상 전산화단층촬영을 이용한 폐기종의 정량적 분석: 폐기능 검사와의 비교)

  • Lee, Jee-Young;Lee, Kye-Young;Choi, Eun-Kyoung;Kim, Sang-Joon;Choi, Young-Hi
    • Tuberculosis and Respiratory Diseases
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    • v.45 no.5
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    • pp.992-999
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    • 1998
  • Background: To correlate the emphysema score for quantification of the overall extent of emphysema in both lungs by CT with physiologic fingings and to get more objective and simple method to assess the extent of emphysema. Method: Thin-section CT and pulmonary function test(PFT) were performed in 17 patients with emphysema (all males, mean age, 62 years). Emphysema score was obtained as percentage of emphysematous lung area, dividing the total area of the emphysema(voxels with attenuation value less than -880, -900, -920HU, respectively) by the overall area of both lungs(voxels with attenuation value less than -400HU) with highlighting voxels using "Density mask" program. Emphysema score was calculated from whole lung(ESV) and 5 representative scans(ESR) using "Density mask", Visual emphysema score(ESV) was obtained by visual assessment from 5 representative scans. Correlation of these emphysema scores(ESW, ESR, ESV) and physiologic findings were performed, comparing the ESW with ESR and ESV. Results: ESW had correlation with DLCO(r=0.53-0.64) and $FEV_1/FVC$(r=0.42-0.57) among PFT parameters. ESR had good correlation with ESW and with PFT parameters as well. ESV did not correlate with PFT parameters except DLCO. Conclusion: CT quantification of emphysema using "density mask" correlated well with physiologic findings. To assess the severity of emphysema, both ESW and ESR are more reliable than ESV, and ESR is recommended in routine practice as it is objective, simple and reliable.

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EXPRESSION OF BMP4, BMP6 FOLLOWING SINUS ELEVATION WITH DBBP IN RABBIT (가토 상악동 점막 거상 후 DBBP를 이식재로 사용시 BMP4, BMP6의 발현)

  • Lee, Hyun-Suk;Heo, Hyun-A;Pyo, Sung-Woon;Lee, Won
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.29 no.6
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    • pp.467-473
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    • 2007
  • The most important factor for successful implantation is osseointegration between the implant and bone. The expression of bone morphogenetic proteins (BMPs) inducing bone formation would differ after maxillary sinus elevation. And within the same graft material. the expression of BMPs would change with time after graft. The aim of this study was to compare the relative expressions of BMP4 and BMP6 using real-time RT-PCR when maxillary sinus elevation was performed using deproteinated bovine bone powder (DBBP) as the graft material or absorbable gelatin sponge (AGS) as the filler without any graft material. Fifteen rabbits, each weighing between 3.0 to 3.5 Kg, were divided randomly into 5 groups of 3 animals each based on their time of sacrifice 0, 3, 5, 7 and 9 days). After exposure of the maxillary sinus bilaterally, bone graft was performed in the right maxillary sinus using DBBP ($BBP^{(R)}$ Oct Inc., Cheonan, Korea) and only AGS ($Gelfoam^{(R)}$ Pharmacia & Upjohn Company, Kalamazoo, MI, U.S.A) was placed into the left without any graft material. Each group of rabbits was sacrificed at 1, 3, 5, 7, or 9 days after operation and all specimens were harvested. And the following results were obtained using real-time RT-PCR from isolated total RNA of the samples. 1. The expression of BMP4 increased at postoperative 1 and 3 days in both DBBP group and AGS group. In AGS group. it decreased at postoperative 5 days. increased again at postoperative 7 days, and decreased at postoperative 9 days. In DBBP group, it increased until postoperative 7 days and decreased at postoperative 9 days. Although the expression of BMP4 was higher in DBBP group compared with AGS group, it was not statistically significant (p>0.05). 2. The expression of BMP6 increased at postoperative 1 and 3 days in both DBBP group and AGS group. In AGS group, it decreased at postoperative 5 days, increased again at postoperative 7 days, and decreased at postoperative 9 days. In DBBP group, it increased until postoperative 7 days and decreased at postoperative 9 days. Although the expression of BMP6 was higher in AGS group compared with DBBP group, it was not statistically significant (p>0.05). 3. There was no statistically significant difference in BMP expression in both groups during same period of time. It' s probably because DBBP and AGS both functioned as a space retainer so that the BMP expression in blood clot seemed to be similar. 4. Thus, DBBP would not offer many benefits for early bone regeneration compared with AGS. The expression of BMP in early bone formation seems to be more influenced by physical carrier rather than the graft type.

Boulangerite from the Janggun Mine, Republic of Korea; Contributions to the Knowledge of Ore-Forming Minerals in the Janggun Lead-Zinc-Silver Ores (2) (한국·장군광산산 보울란저라이트에 대하여; 장군 연·아연·은 구성광물의 지식에 대한 기여 (2))

  • Lee, Hyun Koo;Imai, Naoya
    • Economic and Environmental Geology
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    • v.26 no.2
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    • pp.129-134
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    • 1993
  • At the Janggun mine, boulangerite usually occurs as needles or irregularly-shaped grains, up to $500{{\mu}m}$ in longer dimensions, closely associated with galena, minerals of a tetrahedrite-freibergite series and bournonite in the peripheries of South A and B orebodies and the zone of manganoan carbonates surrounding them. In some places, especially at the top of South B orebody, it occures as "feather ore" consisting of its fine needles or "hairs" in small drusy cavities together with fine-grained euhedral galena, pyrite, manganoan carbonates, quartz, etc. In reflected light, it is bluish grey in colour exhibiting moderate bireflectance and is strongly anisotropic without any internal reflections. Reflectance in air is $R_{max}=43.2$, $R_{min}=35.7$ percent at wavelength of 580 nm, and VHN: $146-173\;kg/mm^2$ at a 50 g-load. The chemical composition on the average from 23 complete spot analyses by electron microprobe is, Pb 56.1, Sb 25.1, S 18.5, Total 99.6 (all in weight percent); the corresponding chemical formula calculated on the basis of S=11 is; $Pb_{5.16}Sb_{3.93}S_{11.0}$ which fulfils approximately the ideal formula $Pb_5Sb_4S_{11}$. The strongest reflections on the X-ray diffraction pattern are; $3.73\;{\AA}\;(10)$, $3.22\;{\AA}\;(5)$, $3.03\;{\AA}\;(4)$ and $2.82\;{\AA}\;(5)$ and the pattern is in harmonic with space group $C^5_{2h}-P2_1/a$. From the textural evidence of the microscopic observations, the mineral is considered to have been formed at the latest stage of hydrothermal lead-zinc-silver mineralization.

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Analysis of the Perception of Radiological Technology University Students about the Latest Technology in the Era of the 4th Industrial Revolution (4차 산업혁명시대 최신 기술에 대한 방사선과 대학생의 인식도)

  • Jang, Hyon-Chol
    • Journal of the Korean Society of Radiology
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    • v.16 no.3
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    • pp.225-231
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    • 2022
  • Transcendence of space and time, virtual reality, augmented reality, etc. are being realized through the latest technologies in the era of the 4th industrial revolution. In a situation where they are currently experiencing artificial intelligence, augmented reality, big data, etc., the degree of interest in the latest technologies of the 4th industrial revolution for radiology students, the necessary competencies in the 4th industrial revolution era, and the prospect of the radiation field employment environment in the 4th industrial revolution era The purpose of this study was to find out the level of awareness of From February 7th to February 18th, 2022, surveys on awareness were analyzed using questionnaires for 2nd and 3rd year students in the Department of Radiology at S University in Daegu. As a result of the study, the level of interest in 3D modeling was shown to be the highest with an average of 3.34 ± 1.09 points, and interest in big data and artificial intelligence was also shown with an average of 3.27 ± 1.17 and 3.33 ± 1.07 points. In addition, the correlation between the awareness of the necessary competencies in the 4th industrial revolution era and the awareness of the prospects for employment in the radiation field in the 4th industrial revolution era was the highest (r=0.778, p<0.01), and the interest in the latest technologies in the 4th industrial revolution and the 4th industrial revolution It was found that there was also a correlation between the perceptions of the necessary capabilities of the times (r=0.694, p<0.01). In the era of the 4th industrial revolution, it is judged that it is necessary to strengthen professional education that can handle the latest technologies such as 3D printing, artificial intelligence, and big data, and to strengthen employment capabilities related to the latest technologies in the field of radiation medical technology.

Synthesis and Structural Study of Extraframework ZrI6Tl119+ Cationic Cluster in Zeolite A (제올라이트 A 동공 내 비골격 ZrI6Tl119+ 양이온 클러스터의 합성과 구조 연구)

  • Hyeon Seung, Lim;Jong Sam, Park;Cheol Woong, Kim;Woo Taik, Lim
    • Korean Journal of Mineralogy and Petrology
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    • v.35 no.4
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    • pp.447-455
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    • 2022
  • Fully dehydrated Tl12-LTA (|Tl12|[Si12Al12O48]-LTA,Tl12-A) was treated with 6.0×103 Pa of ZrI4 (g) at 623 K for 72 hr under anhydrous conditions. The crystal structure of product, |Zr0.25I1.5Tl12|[Si12Al12O48]-LTA, was determined by single-crystal crystallography using synchrotron X-radiation in the cubic space group Pm3m (a = 12.337(2) Å). It was refined using all data to the final error index (for the 712 unique reflections for which Fo> 4σ(Fo) R1/wR2= 0.055/0.189. In this structure, octahedral ZrI62- ions center about 25% of the large cavities (Zr-I = 2.91(4) Å). Each coordinates to eight Tl+ ions and they are further bridged by Tl+ ions in the planes of 8-rings to form a cubic three-dimensional ZrI6Tl119+ cationic cluster. About 1.5 Tl+ ions per unit cell moved to deeper side of sodalite cavity after reaction with ZrI4(g). The remaining Tl+ ions occupy well-established cation positions near 6- and 8-rings.