• Title/Summary/Keyword: incomplete observation

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$CO_2$ Weldability of Zn Coated Steel Sheet(2) -Mechanism of Weld Defect Formation- (아연도금강판의 $CO_2$ 용접특성(2) - 용접결함의 형성기구 -)

  • 이종봉;안영호;박화순
    • Journal of Welding and Joining
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    • v.18 no.2
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    • pp.64-68
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    • 2000
  • The mechanism of the blowhole and the pit formation in lap-jointed fillet Co₂arc welds of Zn-coated steel sheet was established by the direct observation of the gas behavior in the molten pool with the high speed camera system. Main conclusions obtained are as follows: 1) Some blowholes were formed by incomplete back-filling to the pits at the last stage of the solidification. This type of blowhole was formed through four stages of gas in the molten pool, incubation, explosion, back-filling and completion of back-filling stage. 2) Most of the pits was back-filled at the last stage of their formation.

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Transepidermal Water Loss, Stratum Corneum Hydration and Transmission Electron Microscope Observation on Acetone Damaged Canine Skin Barrier Model (아세톤에 의해 손상된 개 피부장벽 모델에서의 경표피수분소실도 및 각질층보습도 평가와 전자현미경적 관찰)

  • Oh, Won-Seok;Park, Seong-Jun;Oh, Tae-Ho
    • Journal of Veterinary Clinics
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    • v.27 no.2
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    • pp.142-146
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    • 2010
  • The purpose of this study is to establish experimental canine skin barrier disruption model in dog. The study was designed to investigate the predictive properties of acetone damage using as effect parameters transepidermal water loss (TEWL) and stratum corneum (SC) hydration. To compare the structures of SC intercellular lipids in normal and acetone damaged skin, TEM observations were performed. Six clinically normal, male Beagles without dermatological problems were chosen for this study. Acetone damage was performed at 48hrs after clipping. Efficacy measurements for TEWL and skin hydration were performed before ($t_1$) and after ($t_2$) damage in a temperature- and humidity-controlled room ($2{0\sim}22^{\circ}C$, 50-60%). TEWL and SC hydration values were decreased in the acetone damaged model compared with non damaged skin. In TEM observation of acetone damaged sample, the intercellular lipid lamellae exhibit abnormal and incomplete structure compared with those of normal skin. It seems that acetone damage would be one of canine skin epidermal barrier disruption model for the study of canine atopic dermatitis (AD) as well as dry skin in veterinary dermatology research.

Changes of Myocardial Ultrastructure During Open Heart Surgery (개심수술중 심근 미세구조의 변화)

  • Hur, Jin;Kong, Joon-Hyuk;Lee, Jong-Tae
    • Journal of Chest Surgery
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    • v.33 no.9
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    • pp.707-715
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    • 2000
  • Background: Cold blood cardioplegic solution has been used to protect myocardium during open heart surgery with the hypothesis stating that it provides more oxygen supply to myocardium compared to crystalloid caridoplegic solution. We repeatedly infused cold blood cardioplegic solution to achieve myocardial protection. We biopsied a small portion of papillary muscle of patients with mitral valve replacement or double valve replacement during aortic cross-clamp time and evaluated the method of myocardial protection through the observation of changes in ultrastructure. We then analysed the relationship between changes in ultrasructure and peak postoperative CK-MB value and SGOT value. Material and method: We report observation on changes of myocardial ultrastructure, postoperative CK-MB and SGOT, and electrocardiogram in 31 patients who underwent cardiac operation. There were 11 males and 20 females, and they ranging in age from 28 to 69 years(mean score was 2.08$\pm$0.560, it was 2.37$\pm$0.558 at 40 minutes, and it was 2.36$\pm$0.523 at 70minutes. Mitochondrial score increased significant at 40 minutes. Mean value of postoperative peak CK-MB and SGOT were 37.3$\pm$17.061IU, 144.5$\pm$125.5IU respectively. We were not able to find any new Q were in EKG after the operation. There was no significant relationship between myocardium mitochondrial score and mean value of postoperative peak CK-MB and SGOT. Conclusion: In conclusion, with this study the cold blood cardioplegic solution was incomplete in preserving ultrastructure of myocardium even with satisfactory results in serum enzyme and EKG evaluation.

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The X-ray Emission Properties of G308.3-1.4 and Its Central X-ray Sources

  • Seo, Kyoung-Ae;Woo, Yeon-Joo;Hui, Chung-Yue;Huang, Regina Hsiu-Hui;Trepl, Ludwig;Woo, Yeon-Joo;Lu, Tlng-Ni;Kong, Albert Kwok Hing;Walter, Fred M.
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.147.2-147.2
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    • 2011
  • We have initiated a long-term identification campaign of supernova remnant candidates in X-ray regime. In the short-listed unidentified sources from the ROSAT All Sky Survey, we have chosen the brightest candidate, G308.3-1.4, as our pilot target for a dedicated investigation with Chandra X-ray Observatory. Our observation has revealed an incomplete shell-like X-ray structure which well-correlated with the radio feature. Together with the spectral properties of a shocked heated plasma, we confirm that G308.3-1.4 is indeed a supernova remnant. A bright X-ray point source which locates close to the remnant center is also uncovered in this observation. Its spectral behavior conform with those observed in a rare class of neutron stars. The properties of its optical/infrared counterpart suggests the evidence for a late-type companion star. Interestingly, possible excesses in B-band and H-alpha have been found which indicate this can be an accretion-powered system. With the further support from the putative periodicity of ~1.4 hrs, this source can possibly provide the direct evidence of a binary system survived in a supernova explosion for the first time.

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Clinical Observation of $Beh{\varsigma}et's$ Disease Patients by Oriental medicine (베체트 병에 대한 임상적 고찰)

  • Kim, Hae-jung;Chae, Byung-yoon
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.12 no.1
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    • pp.387-395
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    • 1999
  • This observation was aimed to evaluate the clinical manifestations and clinical incidence of $Beh{\varsigma}et's$ Disease. It was records of patients seen in the period between January 1992 and December 1998 at the Department of Dermatology, Oriental Medical Hospital, Kyung Hee University. $Beh{\varsigma}et's$ Disease is a chronic, systemic disease which manifests itself as recurrent, multiple lesions in many organs, including the skin. The clinical features of $Beh{\varsigma}et's$ Disease are important as there is no reliable method of laboratory diagnosis. The results were summarized as follows; 1. The total number of patients were 34, including $42\%$ male and $52\%# female. 2. The pick incidence of age group was 30 to 39($44\%$). 3. The most frequent duration was from 2 years to 5 years($41\%$). 4. According to Diagnostic Criteria of the $Beh{\varsigma}et's$ Disease Research committee of Japan, there were $41\%\;of\;Incomplete\;type,\;29\%\;of\;Suspected,\;24\%\;of\;Complete,\;6\%$ of Passible. 5. The most common major symtom is a oral u1cer($91\%$), and there were erythema nodosum like lesion($79\%$), genital ulcer($56\%$), problem of the eyes($38\%$). 6. The most common minor symtom was arthritis($32\%$). 7. The first main symtom were oral ulcer($50\%$), erythema nodosum like lesion($26\%$), problem of the eyes($18\%$). 8. There were 2 cases of Intestinal $Beh{\varsigma}et's$ Disease and 5 cases of uveitis. 9. The most frequently treated prescription was Eunhwasagantang which occupied 79 of all, Gamisopunghwalhultang($44\%$) a.nd Gamipadoksan($41\%$), Gamiguakjungsan($24\%$) in that order of frequency.

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A Proposal of the Evaluation Method of Toner Particle Type Display (토너입자형 디스플레이의 평가방법 제안)

  • Kim, Cheol-Woo;Kim, Young-Cho
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.23 no.9
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    • pp.691-695
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    • 2010
  • A measurement method of the particle-based reflective display is proposed, estimated, and compared with reported method. The reflectivity measurement by previous studies is simply obtained by integrating sphere, but it has a limitation for the estimation of real moving particles because its data include surface reflection and incomplete attachment on electrodes. To get the number of real moving particles, the area by attached particles on the electrodes is calculated at microscopic signals. The moving particles on subthreshold voltage are observed and this fluctuational variation of surface on subthreshold voltage gives a tip to understand the driving mechanism. By this measurement we ascertained the relationship of a particle layer and real driving particles, and the feasibility of observation and estimation for moving color particles, which were measured by the reflectivity and CIE (Commission Internationale de I'Eclairage) system of color specification at previous studies.

Clinical statistics: five key statistical concepts for clinicians

  • Choi, Yong-Geun
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.39 no.5
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    • pp.203-206
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    • 2013
  • Statistics is the science of data. As the foundation of scientific knowledge, data refers to evidentiary facts from the nature of reality by human action, observation, or experiment. Clinicians should be aware of the conditions of good data to support the validity of clinical modalities in reading scientific articles, one of the resources to revise or update their clinical knowledge and skills. The cause-effect link between clinical modality and outcome is ascertained as pattern statistic. The uniformity of nature guarantees the recurrence of data as the basic scientific evidence. Variation statistics are examined for patterns of recurrence. This provides information on the probability of recurrence of the cause-effect phenomenon. Multiple causal factors of natural phenomenon need a counterproof of absence in terms of the control group. A pattern of relation between a causal factor and an effect becomes recognizable, and thus, should be estimated as relation statistic. The type and meaning of each relation statistic should be well-understood. A study regarding a sample from the population of wide variations require clinicians to be aware of error statistics due to random chance. Incomplete human sense, coarse measurement instrument, and preconceived idea as a hypothesis that tends to bias the research, which gives rise to the necessity of keen critical independent mind with regard to the reported data.

SOLAR SHORT-PERIOD OSCILLATIONS EXCITED BY A SMOOTH FORCE

  • CHANG HEON-YOUNG
    • Journal of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.67-72
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    • 2003
  • The basic objective of helioseismology is to determine the structure and the dynamics of the Sun by analysing the frequency spectrum of the solar oscillations. Accurate frequency measurements provide information that enables us to probe the solar interior structure and the dynamics. Therefore the frequency of the solar oscillation is the most fundamental and important information to be extracted from the solar oscillation observation. This is why many efforts have been put into the development of accurate data analysis techniques, as well as observational efforts. To test one's data analysis method, a realistic artificial data set is essential because the newly suggested method is calibrated with a set of artificial data with predetermined parameters. Therefore, unless test data sets reflect the real solar oscillation data correctly, such a calibration is likely incomplete and a unwanted systematic bias may result in. Unfortunately, however, commonly used artificial data generation algorithms insufficiently accommodate physical properties of the stochastic excitation mechanism. One of reason for this is that it is computaionally very expensive to solve the governing equation directly. In this paper we discuss the nature of solar oscillation excitation and suggest an efficient algorithm to generate the artificial solar oscillation data. We also briefly discuss how the results of this work can be applied in the future studies.

DEVELOPMENT OF MOLDABLE BONE REGENERATING THERAPEUTICS USING PARTIALLY PURIFIED PORCINE BONE MORPHOGENETIC PROTEIN AND BIORESORBABLE POLYMER (Poly(L-lactide)와 돼지골기질에서 추출 부분정제한 골형성단백을 이용한 조형가능성 골형성유도체의 개발)

  • Lee, Jong-Ho;Chung, Chong-Pyung;Lee, Sung-Jin
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.26 no.2
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    • pp.179-185
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    • 2000
  • The purpose of this study was to develop an osteogenic, biodegradable material using polymer and BMP. It was designed to have structural function and be moldable, for the reconstruction of load bearing areas and deformities of various configurations. Bone apatite was added to Poly(L-lactide)(PLLA) and made porous for osteoconductability and ease of BMP loading. The materials, with or without BMP purified from porcine bone matrix, were evaluated in cranial bone defect models in rats for biocompatibility and bone regeneration capability. The following results were obtained: The PLLA-BMP material with BMP added to the polymer showed 30% healing of cranial bone defects in rats during the 2 weeks to 3 months period of observation. The moldable PLLA agent without BMP also showed 25% bone healing capacity. Although new bone formation was incomplete in the critical size defect of rat cranium, it can be concluded that the unique moldability of those agents makes them useful for the reconstruction of various bone defects and maxillofacial deformities.

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Origin of Multiple Conductance Peaks in Single-Molecule Junction Experiments

  • Park, Min Kyu;Kim, Hu Sung;Kim, Yong-Hoon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.654-654
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    • 2013
  • One of the most important yet unresolved problems in molecular electronics is the controversy over the number and nature of multiple conductance peaks in single-molecule junctions. Currently, there are three competing explanations of this observation: (1) manifestation of different molecule-electrode contact geometries, (2) formation of gauche defects within the molecular core, (3) involvement of different electrode surface orientations [1]. However, the exact origin of multiple conductance peaks is not yet fully understood, which indicates our incomplete understanding of the scientifically as well as techno-logically important organic-metal contacts. To theoretically resolve this problem, we previously applied a multiscale computational approach that combines force fields molecular dynamics (FF MD), density functional theory (DFT), and matrix Green's function (MGF) calculations [2] to a thermally fluctuating haxanedithiol (C6DT) molecule stretched between flat Au(111) electrodes, but could observe only a single conductance peak [3]. In this presentation, using DFT geometry optimizations and MGF calculations, we consider molecular junctions with more realistic molecule-metal contact conformations and Au(111) electrode surface directions. We also conduct DFT-based molecular dynamics for the highly stretched junction models to confirm our conclusion. We conclude that the S-Au coordination number should be the more dominant factor than the electrode surface orientation.

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