• 천문학회지
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• 제48권6호
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• pp.381-398
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• 2015

Dynamical analysis of compact groups provides important tests of models of compact group formation and evolution. By compiling 2066 redshifts from FLWO/FAST, from the literature, and from SDSS DR12 in the fields of compact groups in , we construct the largest sample of compact groups with complete spectroscopic redshifts in the redshift range 0.01 < z < 0.22. This large redshift sample shows that the interloper fraction in the compact group candidates is ~ 42%. A secure sample of 332 compact groups includes 192 groups with four or more member galaxies and 140 groups with three members. The fraction of early-type galaxies in these compact groups is 62%, higher than for the original Hickson compact groups. The velocity dispersions of early-and late-type galaxies in compact groups change little with groupcentric radius; the radii sampled are less than 100 h⁻¹ kpc, smaller than the radii typically sampled by members of massive clusters of galaxies. The physical properties of our sample compact groups include size, number density, velocity dispersion, and local environment; these properties slightly differ from those derived for the original Hickson compact groups and for the DPOSS II compact groups. Differences result from subtle differences in the way the group candidates were originally selected. The abundance of the compact groups changes little with redshift over the range covered by this sample. The approximate constancy of the abundance for this sample is a potential constraint on the evolution of compact groups on a few Gigayear timescale.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제30권4호
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• pp.370-379
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• 2008

Objective: This study was carried out to evaluated the psychologic changes of skeletal Class III malocclusion individuals by orthognathic surgery. Methods: One hundred and thirty seven adults skeletal Class III malocclusion individuals were selected for this study. Fifty two for pre-surgery group, forty two for 2-months after orthognathic surgery group and forty three for 6-months after orthognathic surgery group. Each group was investigated by questionnaires related to self-concept standard developed by Dr. Lee. The questionnaires included physical self-concept, ethic self-concept, characteristic self-concept, domestic self-concept, the social self-concept and capable self-concept. Each group was compared by one-way ANOVA. Results: Only the physical self-concept showed significant changes after orthognathic surgery, however it did not showed differences between after 2-months and after 6-months. But other self-concept did not show significant changes by orthognathic surgery. Conclusion: At first, it is expected that many variables related to self-concept were influenced by orthognathic surgery. But only physical self-concept showed significant change by orthognathic surgery.

• 문화기술의 융합
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• 제6권1호
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• pp.241-247
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• 2020

16세기에 말에 들어 해부학의 중심지로 부상한 네덜란드 레이던에서는 시민들을 위한 해부학 극장이 개관되었다. 새롭게 시작된 인체 해부 활동은 의학의 발전에 기여했음은 물론이고, 시민들을 청중으로 하여 진행된 공개 해부 시연은 해부 관람이 하나의 고급문화 활동으로 자리 잡게 만들었다. 레이던에서 시작된 해부에 대한 대중의 관심은 암스테르담으로까지 퍼졌고, 17세기 네덜란드의 대표 화가 렘브란트의 작품 <튈프 박사의 해부학 강의>에서 직접 해부를 수행하고 있는 모습으로 등장하는 주인공 튈프는 그러한 변화의 중심에 위치했던 인물이었다. 튈프는 의사이자 의료 행정 개혁가로도 큰 업적을 남겼고, 그의 해부 강연은 암스테르담에서 큰 인기를 끌었다. 해부 강연에 의해 인체 해부는 징그러운 광경이 아니라 문화 시민이라면 충분히 관심을 가질만한 행위로 받아들여지게 되었고, 렘브란트가 작품의 주제로 튈프가 시체를 해부하고 있는 광경을 선택한 데에는 이러한 배경이 있었다. 렘브란트는 이러한 시민들의 생각의 변화를 읽어내고 화폭에 담아내면서 과학과 예술의 융합을 시도했던 것이다.

• 한국발생생물학회지:발생과생식
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• 제21권4호
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• pp.425-434
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• 2017

Polyploidy is occurred by the process of endomitosis or cell fusion and usually represent terminally differentiated stage. Their effects on the developmental process were mainly investigated in the amphibian and fishes, and only observed in some rodents as mammalian model. Recently, we have established tetraploidy somatic cell nuclear transfer-derived human embryonic stem cells (SCNT-hESCs) and examined whether it could be available as a research model for the polyploidy cells existed in the human tissues. Two tetraploid hESC lines were artificially acquired by reintroduction of remained 1st polar body during the establishment of SCNT-hESC using MII oocytes obtained from female donors and dermal fibroblasts (DFB) from a 35-year-old adult male. These tetraploid SCNT-hESC lines (CHA-NT1 and CHA-NT3) were identified by the cytogenetic genotyping (91, XXXY,-6, t[2:6] / 92,XXXY,-12,+20) and have shown of indefinite proliferation, but slow speed when compared to euploid SCNT-hESCs. Using the eight Short Tendem Repeat (STR) markers, it was confirmed that both CHA-NT1 and CHA-NT3 lines contain both nuclear and oocyte donor genotypes. These hESCs expressed pluripotency markers and their embryoid bodies (EB) also expressed markers of the three embryonic germ layers and formed teratoma after transplantation into immune deficient mice. This study showed that tetraploidy does not affect the activities of proliferation and differentiation in SCNT-hESC. Therefore, tetraploid hESC lines established after SCNT procedure could be differentiated into various types of cells and could be an useful model for the study of the polyploidy cells in the tissues.

• Advances in nano research
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• 제7권6호
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• pp.443-457
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• 2019

In this investigation, dynamic and bending behaviors of isolated protein microtubules are analyzed. Microtubules (MTs) can be considered as bio-composite structures that are elements of the cytoskeleton in eukaryotic cells and posses considerable roles in cellular activities. They have higher mechanical characteristics such as superior flexibility and stiffness. In the modeling purpose of microtubules according to a hollow beam element, a novel single variable sinusoidal beam model is proposed with the conjunction of modified strain gradient theory. The advantage of this model is found in its new displacement field involving only one unknown as the Euler-Bernoulli beam theory, which is even less than the Timoshenko beam theory. The equations of motion are constructed by considering Hamilton's principle. The obtained results are validated by comparing them with those given based on higher shear deformation beam theory containing a higher number of variables. A parametric investigation is established to examine the impacts of shear deformation, length scale coefficient, aspect ratio and shear modulus ratio on dynamic and bending behaviors of microtubules. It is remarked that when length scale coefficients are almost identical of the outer diameter of MTs, microstructure-dependent behavior becomes more important.

• Annals of Laboratory Medicine
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• 제38권6호
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• pp.518-523
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• 2018

Background: Lipemia, a significant source of analytical errors in clinical laboratory settings, should be removed prior to measuring biochemical parameters. We investigated whether lipemia in serum/plasma samples can be removed using a method that is easier and more practicable than ultracentrifugation, the current reference method. Methods: Seven hospital laboratories in Spain participated in this study. We first compared the effectiveness of ultracentrifugation ($108,200{\times}g$) and high-speed centrifugation ($10,000{\times}g$ for 15 minutes) in removing lipemia. Second, we compared high-speed centrifugation with two liquid-liquid extraction methods-LipoClear (StatSpin, Norwood, USA), and 1,1,2-trichlorotrifluoroethane (Merck, Darmstadt, Germany). We assessed 14 biochemical parameters: serum/plasma concentrations of sodium ion, potassium ion, chloride ion, glucose, total protein, albumin, creatinine, urea, alkaline phosphatase, gamma-glutamyl transferase, alanine aminotransferase, aspartate-aminotransferase, calcium, and bilirubin. We analyzed whether the differences between lipemia removal methods exceeded the limit for clinically significant interference (LCSI). Results: When ultracentrifugation and high-speed centrifugation were compared, no parameter had a difference that exceeded the LCSI. When high-speed centrifugation was compared with the two liquid-liquid extraction methods, we found differences exceeding the LCSI in protein, calcium, and aspartate aminotransferase in the comparison with 1,1,2-trichlorotrifluoroethane, and in protein, albumin, and calcium in the comparison with LipoClear. Differences in other parameters did not exceed the LCSI. Conclusions: High-speed centrifugation ($10,000{\times}g$ for 15 minutes) can be used instead of ultracentrifugation to remove lipemia in serum/plasma samples. LipoClear and 1,1,2-trichlorotrifluoroethane are unsuitable as they interfere with the measurement of certain parameters.

• Computers and Concrete
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• 제17권6호
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• pp.801-814
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• 2016

An alternative type of building system with masonry units is extensively used nowadays to reduce the emission of CO2 and embodied energy. Long-term performance of such structures has become essential for sustaining the building technology. This study aims to assess the strength and durability properties of concrete prepared with unprocessed bagasse ash (BA) and silica fume (SF). A mix proportion of 1:3:3 was used to cast concrete cubes of size $100mm{\times}100mm{\times}100mm$ with various replacement levels of cement and tested. The cubes were cast with zero slump normally adopted in the manufacturing of hollow blocks. The cubes were exposed to acid attack, alkaline attack and sulphate attack to evaluate their durability. The mass loss and damages to concrete for all cases of exposures were determined at 30, 60, and 90 days, respectively. Then, the residual compressive strength for all cases was determined at the end of 90 days of durability test. The results showed that there was slight difference in mass loss before and after exposure to chemical attack in all the cases. Though the appearance was slightly different than the normal concrete the residual weight was not affected. The compressive strength of 10% bagasse ash (BA) as a replacement for cement, with 10% SF as admixture resulted in better strength than the normal concrete. Hence concrete with 10% replacement with BA along with 10% SF as admixture was considered to be durable. Besides solid concrete cubes, hollow blocks using the same concrete were casted and tested simultaneously to explore the possibility of production of masonry units.

• 한국콘텐츠학회논문지
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• 제19권8호
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• pp.151-158
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• 2019

국내 전기 전자 산업이 보유하고 있는 높은 기술력은 국외 시장에서도 인정받고 있지만 현재 주변국과의 기술경쟁 등이 갈수록 심화되어져 가고 있는 상황이다. 따라서 이들 기업들이 경쟁우위를 차지하기 위해서는 무엇보다 운영상의 비효율성을 재정비하여 효율적인 생산 활동을 실시하여야한다. 이에 본 논문에서는 DEA 기업을 통해 국내 고성장 전기 전자사업의 경영효율성을 분석하며 비효율적인 기업의 투사값을 제시하며 벤치마킹의 대상이 될 수 있는 기업들의 참조집합을 확인하고자 한다. 이를 위해 총 20개 고성장 전기 전자기업들의 CCR와 BCC모형의 효율성과 규모수익성(RTS)을 분석하였다. 분석결과 BCC 효율성이 1인 기업은 총 12개, CCR 효율성이 1인 기업은 총 4개 기업으로 나타났다. 그리고 BCC, CCR 효율성이 모두 1인 기업은 총 4개 기업이었다. 또한 기업의 규모수익성은 IRS가 11개 기업, CRS가 6개 기업 그리고 DRS가 3개 기업으로 분석되었으며 참조빈도 분석에서는 BCC모형에서는 4개 기업과 CCR 모형을 통해 4개 기업을 벤치마킹이 할 수 있는 기업으로 제시하였다. 이러한 결과는 동종 산업의 후발 기업들에게 기업의 운영환경을 개선할 수 있는 유용한 정보가 될 것이다.

• 산업융합연구
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• 제18권6호
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• pp.27-32
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• 2020

최근 IT를 활용한 비즈니스가 급증함에 따라 복잡해진 IT 인프라를 운영 관리하는데 있어 많은 예산이 소요되고 있다. 이에 대한 효율적이고 비용절감 효과를 얻을 수 있는 새로운 IT 인프라 기술이 필요한 실정이다. 본 논문에서는 정보 시스템의 단순화와 운영 관리의 효율성 및 비용 절감을 위한 IT 인프라 방식인 CI(Converge Infrastructure)과 HCI(Hyper Converge Infrastructure) 방식을 소개한다. 또한 새로운 IT 인프라 기술인 HCI 방식을 활용한 정보 시스템 및 재해 및 장애 발생 시 서비스의 연속성을 제공하기 위한 재해복구시스템의 구축 방안에 대해서 제시한다. HCI 방식을 활용하기 위한 주요 기술 소개와 함께 HCI 도입 전후의 정보 시스템실의 면적 및 소비전력, 운영의 효율성 등을 비교분석 한다.

• Journal of Korean Neurosurgical Society
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• 제64권4호
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• pp.608-618
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• 2021

Objective : The endoscopic endonasal transsphenoidal approach is a widely-used method for the surgical treatment of pituitary adenomas. We aimed to evaluate the results of endoscopic surgery by comparing preoperative classification methods and investigating their relationship with postoperative resection and remission rates and complications. Methods : We retrospectively reviewed the medical records of 236 patients (118 males) who underwent surgery for pituitary adenomas. Preoperative Knosp classification, tumor size (TS), suprasellar extension (SSE), postoperative resection and remission rates, and complications were evaluated. Results : The follow-up period was 3 months to 6 years. The patients' ages ranged between 16 and 84 years. Endocrinologically, 114 patients (48.3%) had functional adenoma (FA), and 122 patients (51.7%) had non-functional adenoma (NFA). Among the FA group, 92 (80.7%) showed remission. A statistically significant difference was found between patients with and without remission in terms of the Knosp, TS, and SSE classifications (p<0.01). Knosp, TS, and SSE classification grades were found to be correlated with the resection rates (p<0.01). Meningitis was seen in seven patients (3.0%), diabetes insipidus in 16 (6.9%; permanently in two [0.9%]), and rhinorrhea in 19 (8.1%). Thirty-six patients (15.3%) developed pituitary insufficiency and received hormone replacement therapy. Conclusion : The resection categories and remission rates of FAs were directly proportional to the adenoma sizes and Knosp grades, while the degree of suprasellar growth further complicated resection and remission rates. Adenoma sizes less than 2 cm and SSEs less than 1 cm are associated with favorable remission and resection rates.