• Journal of Radiopharmaceuticals and Molecular Probes
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• v.5 no.2
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• pp.71-78
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• 2019

Nuclear imaging is one of the most powerful measures for non-invasive diagnosis of myocardial vascular disease. Radionuclide such as ¹³N, ¹⁵O, ²⁰¹Tl and ⁸²Rb is used for the measurement of cardiac blood flow. ¹³N, ¹⁵O and ²⁰¹Tl are produced in cyclotrons while ⁸²Rb is obtained from generator. Rubidium (Rb), an alkali ion, behaves biologically like potassium, and accumulates in myocardial tissue. Rb has rapid blood clearance profile which allows the use of ⁸²Rb with a short physical half-life of 75 s for non-invasive evaluation of regional myocardial perfusion. There are several advantages of ⁸²Rb over other radioisotopes. An ultra-short half-life significantly reduces the exposure of patients to radiation and allows to repeat injections for studying the effects of medical intervention. As a positron emitter, ⁸²Rb allows positron emission tomography (PET) imaging which have shown superior diagnostic performances. ⁸²Rb can be produced from generator by decay of its parent ⁸²Sr. However, the preparation of ⁸²Sr is difficult, because appropriate purity is required to meet the specification of the product. Recently reported procedure from ARRONAX research institute showed that a Chelex-100 resin is sufficient for this purpose and additional column is not necessary. Whereas Brookhaven National Laboratory (BNL) procedure contains three ion exchange resin separation, including Chelex-100 resin. Currently, since ⁸²Sr production site is non-existent in Korea, Korea Atomic Energy Research Institute (KAERI) has plan to produce ⁸²Sr within specifications. We compared ⁸²Sr purification procedures reported from ARRONAX and BNL to investigate the most suitable procedure for our conditions.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.579-584
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• 2019

The flight characteristics of 11 cinereous vultures (Aegypius monachus) were analyzed by a global positioning system (GPS) tracker(WT-300; KoEco, Inc.). The wintering period in Korea averaged 131 days (SD=17.4) and the average flight rate was 19.6%. The flight altitude was below 100 m for 21.6% of the flight, 101-200 m for 25.3%, 201-300 m for 19.0%, and below 300 m for 65.9%. There was a positive correlation (r=0.929) between the hourly flight rate and altitude. The predominant monthly flight altitude was 101-200 m (p<0.05). The wintering cinereous vultures lowered their flight rate and flew at an altitude of less than 300 m. This is thought to be an efficient way to find food through social interaction.

• Korean Journal of Agricultural Science
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• v.2 no.1
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• pp.281-300
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• 1975

The precipitation data and water level data in twenty-four sampling places, to investigate same hydrological quantities along the basin of Geum River, have been analyzed, and the findings for the first report are summarized as follows. 1. The mean annual precipitation in the basin of Geum River is of 1203mm, and the areal weight of areal rainfall by Thiessen's method shows as Table 1. 2. The areas where have maximum annual precipitation of 1501 to 2000mm, are seventeen placed among twentyfour gauging stations, and it is founded to be the highest rate with 71 percents. The precipitation of below 1500mm is measured in the other three statinons, and that of above 2001mm in four stations, too. 3. The areas where have maximum rainfall of 201 to 300mm within a day, are fifteen places, and that comes in the highest rate of distribution with 63 percents. 4. As to distribution of the places with maximum rainfall of below and above 300mm within two days, it shows respectively 50 percents. 5. The areas where have maximum rainfall of 301 to 400mm within three days, are fifteen places, and it is the highest rate of distribution with 63 percents. 6. The fourteen places have maximum rainfall of 401 to 600mm within a continuous day, it is the highest rate of distribution with 58 percents. 7. Table 5 shows probable maximum rainfall within a day, and it does the most rainfall a long the upper stream of Daecheong dam site around Muju, and the next shows in the areas around Ganggyeung, Gongju and Buyeu. 8. During irrigation period on paddy corp, for 100 days from early ten days in June to early ten days in September the areas where have rainfall of 601 to 800mm are sixteen places, and it is the highest rate of distribution with 76 percents, as Table 6 9. The areas where have effective rainfall of 501 to 600mm, are fifteen places, and it is the highest rate of distribution with 71 percents. Thirteen places have the effective ratio of 66 to 75 percents, and it means 62 percents of distribution, and the next, 76 to 85 percents in the seven places, and it comes 33 percents. 10. The areas where have probable effective rainfall of 401 to 500mm, are fourteen places, which is about 100mm less than mean effective rainfall in each area, and that comes 67 percents of distribution. 11. A particular year can not be appointed as once -in-10 year drought in the same year as a whole in the basin of Geum River. 12. The basin of Geum River, s/S being 0.53 to 0.74, has relatively proper conditions in the aspect of water resources.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2007.12a
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• pp.200-201
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• 2007

The present study was conducted in three fields at Namhae to examine the removal efficiency of organic free, heavy metal immobilized sediment on Cochlodinium polykrikoidesand and on sea water quality. The present study results concluded that removal efficiency was depends on the initial number of red tide cells. There was no drastic change in the sea water quality after sediment spray. For the comparison of effectiveness of betonite, zeolite and lime were mixed with sediment did not show any marked difference in removal. Finally, the present study evaluated 50g/$m^{2}$ sediment is sufficient to remove 100% cells density, even though various environmental factors are interfering the mechanism.

• Clinical and Experimental Reproductive Medicine
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• v.27 no.2
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• pp.159-164
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• 2000

연구목적:인간의 체외수정 및 배아이식술에서 난관수종을 갖는 환자에서 임신율과 착상률이 감소된다는 보고들이 있지만 이에 대한 명확한 기작은 밝혀지지 않았다. 본 연구에서는 생쥐 배아를 이용한 체외 착상모델에서 인간의 난관수종액(HSF)이 착상과정에 미치는 영향을 알아보고자 하였다. 연구재료 및 방법 난관수종액은 난관수종으로 수술을 받은 8명의 환자로부터 채취하였으며, 실험에 사용하기 전까지 냉동고에 보관하였다. 생쥐의 포배기 배아는 2-세포기배아를 3일 동안 배양하여 그 중 상태가 양호한 포배기 배아만을 선별하여 투명대를 제거한 후 사용하였다. 기본 배양액으로는 Ham's F-10을 사용하였으며, 배양 시 기본 배양액만을 사용한 경우를 group Ⅰ으로 하였고, 기본 배양액에 0.5% FBS를 첨가한 경우를 group Ⅱ, 0.5% FBS와 50% HSF를 첨가한 경우를 group Ⅲ , 100% HSF에 0.5% FBS를 첨가한 경우를 group Ⅳ,100% HSF만을 사용한 경우를 group Ⅴ로 하였다. 투명대를 제거한 포배기 배아를 각각의 HSF에 대한 5종류의 배양액에서 48시간 동안 배양하였다. 체외 착상 유무는 부착 부위에서 크기가 커진 영양세포들을 관찰하여 판정하였으며, 착상 부위의 표면적은 화상분석기를 이용하여 산출하였다. 결 과: 생쥐 배아의 체외 착상률은 group Ⅰ, Ⅱ, Ⅲ, Ⅳ, Ⅴ에서 각각 0%, 98.9%, 77.5%, 40.4%, 10.0%로 나타났으며, 착상 부위의 평균 표면적은 group Ⅱ, Ⅲ, Ⅳ, Ⅴ에서 각각 $74,675{\pm}25,201{\mu}m^2$, $59,024{\pm}25,877{\mu}m^2$, $45,156{\pm}22,654{\mu}m^2$, $38,254{\pm}17,115{\mu}m^2$이었다. 체외 착상률과 부위의 표면적은 HSF의 농도가 증가함에 따라 통계적으로 유의하게 감소하였다(p<0.001). 결론:인간의 난관수종액(HSF)은 생쥐 배아의 체외 착상과 영양배엽세포의 증식을 억제하는 것으로 확인되었으며, 이러한 원인이 난관수종을 갖는 환자에서 임신율이 낮은 것과 밀접한 관련이 있을 것으로 생각된다.

• Journal of Korean Institute of Industrial Engineers
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• v.28 no.2
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• pp.201-215
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• 2002

In this paper, we use a structural equation model to diagnose success factors on commercialization of information and communication technology considering the characteristics of commercialization process in terms of the type of technology, technology provider and technology receiver. The results of our study indicated the following. The transferor's research ability has significant effects on the commercialization by small businesses with low R&D expenditure to sales ratio, and the business management ability plays an important role in the commercialization by the relatively large (over 100 employees) companies with low R&D expenditure ratio. During the commercialization of the technology independently researched by government run institute or university, the transferee's business management ability is crucial to success. To those companies which run the existing business with high R&D expenditure ratio, their ability to utilize technology is essential. When the independently researched technology is used in the new business, the companies' business management ability and the role of technology transfer center are the important factors on the commercialization. Based on these findings, we suggest some strategies to effectively promote R&D efforts for successful commercialization.

• Journal of Microbiology and Biotechnology
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• v.15 no.1
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• pp.188-191
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• 2005

Abstract Cyclosporins are a family of clinically-important immunosuppressive cyclic peptides produced by Tolypocladium inflatum. The structural modification of cyclosporins via hydroxylation at various positions of N-methyl leucines in cyclosporin A leads to a dramatic change of their bioactive spectra. Among over 100 soil actinomycetes screened, two actinomycetes species, Sebekia benihana and Pseudonocardia autotrophica, were identified to contain superior cyclosporin A hydroxylation activities. A HPLC-based cyclosporin A hydroxylation assay revealed that each strain possesses distinctive hydroxylation specificity and regiospecificity; mono-hydroxylation at the 4th N-methyl leucine of cyclosporin A by S. benihana, and di-hydroxylations at both 4th and 9th N-methyl leucines of cyclosporin A by P. autotrophica. The conversion yields for cyclosporin A hydroxylation by both S. benihana and P. autotrophica were significantly improved from less than 10% and 18% up to 58% and 45%, respectively, in the optimized culture containing molybdenum with 0.05 g/l of cyclosporin A concentration. An ancymidol-specific inhibition of cyclosporin hydroxylation also suggested that the regiospecific cyclosporin hydroxylation might be catalyzed by a putative cytochrome P450 mono-oxygenase enzyme.

• KCI Concrete Journal
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• v.11 no.3
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• pp.201-210
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• 1999

An experimental study was carried out to determine pullout behavior of a new type of anchor bolt that used deformed reinforcement and a commercial adhesive. Concrete slabs and columns with about 20-MPa compressive strength were used for 136 pullout tests performed. Test variables included anchor diameter (10 mm ~ 32 mm). embedment depth (10$\Phi$ or 15$\Phi$), edge effect. and Presence of transverse reinforcement in existing concrete. In Tyre-S test. where the edge or reinforcing steel effect was not included, the anchor Pullout strengths increased with increasing anchor diameters. Anchors with 15$\Phi$ embedment depth had higher Pullout strengths than those with 100 embedment depth The largest average Pullout load of 208 kN was determined for anchors made with D25 reinforcement and with 15$\Phi$ embedment depth. In Type-E tests, where the anchors were installed close to the edge of existing concrete, there were reductions in pullout strengths when compared to those determined in Type-S tests. In Type-ER tests, influence of the reinforcement in existing concrete on the anchor pullout strengths was examined using reinforced concrete and plain concrete columns Test results indicated that existing transverse reinforcement (column ties) did not help increase the pullout strength. The overall pullout test results revealed that the new anchor bolt can develop large pullout strengths while the anchors can be made of materials that are readily available in the market.

• Journal of Broadcast Engineering
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• v.26 no.7
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• pp.855-861
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• 2021

Neural Architecture Search (NAS) is cutting-edge technology in the machine learning community. NAS Without Training (NASWOT) recently has been proposed to tackle the high demand of computational resources in NAS by leveraging some indicators to predict the performance of architectures before training. The advantage of these indicators is that they do not require any training. Thus, NASWOT reduces the searching time and computational cost significantly. However, NASWOT only considers high-performing networks which does not guarantee a fast inference speed on hardware devices. In this paper, we propose a multi objectives reward function, which considers the network's latency and the predicted performance, and incorporate it into the Reinforcement Learning approach to search for the best networks with low latency. Unlike other methods, which use FLOPs to measure the latency that does not reflect the actual latency, we obtain the network's latency from the hardware NAS bench. We conduct extensive experiments on NAS-Bench-201 using CIFAR-10, CIFAR-100, and ImageNet-16-120 datasets, and show that the proposed method is capable of generating the best network under latency constrained without training subnetworks.

• Korean Journal of Microbiology
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• v.41 no.1
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• pp.24-37
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• 2005

This study was conducted to analyze the molecular epidemiological properties and to select the most efficient and reliable PCR method on 116 of Staphylococcus aureus (S. aureus) isolates from Korean cattle, black goat, pig, dog, chicken, mouse and also human clinical cases from hospital. The distribution patterns of SSG [species specific genes; coagulase (coa), protein A (spa), nuclease (nuc) and aroA (RsaI) gene] were analyzed by PCR method. Among the SSGs, the nuc-gene was found in all strains $(100\%)$ tested and followed by coa-gene $(87.9\%)$, spa-gene $(91.4\%)$ and aroA-gene $(26.7\%)$, in order. The genetic subtyping by RFLP method was performed on the coa [AluI] and aroA-gene [RsaI] PCR products. The mecA-gene PCR and PCR-RFLP techniques were chosen to detect and verify of MRSA strains. Only the human strains $(12.1\%)$ were detected the positive mecA-gene products (533 bp), which were divided into two specific bands [201 & 332 bp] by HhaI enzyme digestion. On coa-gene and spa-gene typing, coa-gene was typed with ten kinds of genotype and coa-3 type were determined as the most predominant genotype, while spa-gene was divided into eleven kinds of genotype and also spa-7 type were selected the most prevalent genotype based on their genetic variations. On the aroA and coa-gene subtyping by PCR-RFLP, aroA-gene products were discriminated with only seven types of genotype, while coa-gene products were further divided into an eleven genotype, respectively. In comparison of SID values of five PCR based typing methods, the coa-PCR-RFLP (SID0.894) was evaluated the most efficient and reliable tools and followed by coa-PCR (SID0.883) and aroA-PCR-RFLP (SID0.462), in order. In conclusion, we could determined that the coa-PCR-RFLP method was the most suitable genetic analysis tool for S. aureus and MRSA strains from domestic animals and humans.