• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.141.2-141.2
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• 2015

교류임피던스 측정기법을 이용하여 전기화학적으로 외부환경에서 소재 금속까지 물질 및 전하이동에 관한 임피던스 측정이 가능하며 도막의 부식 및 노화정도 및 내식성의 평가가 가능하여 산업체에서 널리 이용되고 있다. RPCS(Remote Plasma Cleaning Source)는 패널 및 반도체 제조공정에서 CVD 증착공정 후 챔버 내부에 입혀지는 Si(실리콘)을 화학적으로 세정하기 위한 F(불소) Radical을 공급하는 원격 고밀도 플라즈마를 발생시키는 제품이다. RPCS의 바디는 알루미늄을 사용하고 절연 및 플라즈마에 대한 내구성을 확보하기 위해 아노다이징 코팅을 한다. 반응기 내벽의 표면이 공정 플라즈마에 노출될 때 소재는 화학적으로 매우 활성이 높은 라디칼과의 반응뿐만 아니라 이온의 충격을 동시에 받게 되며 이 과정에서 다량의 불소 (Fluorine) 라디칼과 전계에 반응한 이온의 운동에 노출되면서 아노다이징 코팅이 손상되는데 이는 기기의 수명 단축 및 파티클을 발생시키며, Arc의 원인이 되기도 한다. 실제 사용 환경에서는 기기의 분해 없이 아노다이징의 상태를 주기적으로 모니터링 하기가 대단히 어려워, 정기적으로 교체하고 있는 실정이다. 본 연구에서는 RPCS내 발생된 플라즈마 현상을 컨덕터로 활용하여 고주파 리액턴스를 임피던스로 환산하여 아노다이징 코팅의 손상 정도를 진단 및 모니터링하였다. 아노다이징이 손상된 내부 블럭과 정상상태인 내부 블럭의 임피던스를 비교하였고, 아노다이징 두께별 임피던스를 측정하였다. 그 결과 아노다이징 절연막이 손상된 블록의 임피던스가 정상 블록에 비해 낮았으며 두께별 임피던스도 비례함을 알 수 있었다. 향후에는 장기간 현장에서 축척되어진 시험데이터를 바탕으로 아노다이징 코팅의 수명예측진단 시스템을 구축하고자 한다.

• Journal of the Korean Wood Science and Technology
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• v.42 no.4
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• pp.439-449
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• 2014

RPS (Renewable Portfolio Standard) has increased wood pellet demand dramatically in recent years in Korea where self-supply rate of wood pellet is not more than 10%. However global production capacity of wood pellet is prospected to be unable to meet the global demand after 2020. Therefore it is urgently needed to develop new sustainable biomass energy resources which can replace wood pellet at lower cost. As a result of this study EFB (empty fruit bunch) and MF (mesocarp fiber), the representative solid palm biomass, are estimated to be generated at the rate of 20 and 28 million tons per year (based on 10% moisture content) in Malaysia and Indonesia, respectively in 2012. Total annual generation rate of EFB and MF is estimated as 48 million tons per year only in Malaysia and Indonesia in 2012. With calorific value of over 90% of wood pellet EFB is expected to be a excellent biomass energy resource which can replace wood pellet. EFB can be utilized as fuel for power generation or industrial purpose. However EFB may not be a proper fuel for domestic and greenhouse heating because of its high ash content.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.41
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• pp.58.1-58.8
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• 2019

Background: The aim of this study is to investigate the relationship between gender-specific and obesity-related airway anatomy in patients with obstructive sleep apnea (OSA) by using cephalometric analyses. Methods: We retrospectively evaluated 206 patients with suspected OSA undergoing polysomnography and anthropometric measurements such as body mass index, neck circumference, and waist-hip ratio. We checked lateral cephalometry to measure tissue landmarks including angle from A point to nasion to B point (ANB), soft palate length (SPL), soft palate thickness (SPT), retropalatal space (RPS), retrolingual space (RLS), and mandibular plane to hyoid (MPH). Results: Male with OSA showed significantly increased SPL (P = .006) compared with controls. SPL and MPH had significant correlation with apnea-hypopnea index (AHI) and central obesity. Female with OSA showed significantly increased ANB (P = .013) and SPT (P = .004) compared with controls. The receiver operating characteristic curves revealed that SPT in male and ANB and SPT in female were significant in model 1 (AHI ≥ 5) and model 2 (AHI ≥ 15). MPH was also significant for male in model 2. Conclusion: Male and female with OSA had distinct anatomic features of the upper airway and different interactions among soft palate, mandible, and hyoid bone.

• Environmental and Resource Economics Review
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• v.25 no.2
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• pp.229-253
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• 2016

To achieve the socially optimum level of renewable generation, governments should design renewable policies to induce renewable technologies competitive with conventional generation technologies. And to do that, it is needed to understand how each policy has been effective in promoting renewables for power sector. In most of the literatures, there are two key limitations that they did not considered autocorrelation problem using the amount of generation from renewables as a dependent variable and technology innovation which needs to be preceded technology adoption. In this study, I try to overcome these two problems by using dynamic panel model and adding an additional variable for technology innovation. According to the result, FIT has been effective rather than RPS in promoting renewables for generation and I found the possibility that the counterintuitive results which commonly appeared in existing studies might be due to the two limitations mentioned above.

• The Journal of Korean Academy of Prosthodontics
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• v.35 no.2
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• pp.373-384
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• 1997

In this study, 4 types of dowel pin were used to fabricate removable dies using the Pindex system. The comparison of interabutment distances between before and after sawing were conducted in each type of dowel pin, and the horizontal discrepancies in the interabutment distance according to the abutment location and the type of dowel pin were comparatively analyzed. Abutments LM(left molar), LP(left premolar), A(anterior), RP(right premolar), and RM (right molar) were used for measurement. The interabutment distances were measured between each abutment : LM-LP, LM-A, LM-RP, and LM-RM. The slide scanned image of each model was magnified on the computer screen and the measurements were conducted using the meeting point of the cross on the occlusal surface of each abutment. The results were as follows : 1. In the comparison of interabutment distances between before and after sawing in each type of dowel pin, there was no significant difference in World dowel pin(double), Bi-pin(double), Maxcel dowel pin(single). In the World dowel pin(single) there was no significant difference between LM-LPs, but in the other measurements (LM-As, LM-RPs, and LM-RMs) there was significant difference between before and after sawing(p<0.05). 2. In comparison of horizontal discrepancies of the measurement according to the abutment location, there was significant difference between measurement LM-LP($0.27{\pm}0.19mm$) and the others : LM-A($0.46{\pm}0.20mm$), LM-RP($0.38{\pm}0.25mm$), LM-RM($0.45{\pm}0.22mm$) (p<0.05). 3. In comparison of horizontal discrepancies of the measurement according to the type of dowel, there was no significant difference between each dowel. As a result when fabricating a removable die using the previously mentioned 4 types of dowel pins, it is thought that the horizontal discrepancy increased in proportion to the interabutment span length and does not depend on the type of dowel pin.

• Journal of fish pathology
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• v.22 no.3
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• pp.327-334
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• 2009

This study was performed to verify the efficacy and safety of vaccine mixed formalin killed Edwardsiella tarda and formalin killed Streptococcus iniae in olive flounder Paralichthys olivaceus. Sera were obtained from each group at 2, 4, 6 and 8 weeks after vaccination and agglutination titers to E. tarda and S. iniae were determined using the microtiter method. Three weeks after vaccination, the fish challenged by intraperitoneal injection of E. tarda or S. iniae and immunization resulted in a relative percentage survival (RPS) of above 81.0-92.8%. Neither the groups vaccinated nor control groups resulted in significantly reduced weight gain 140 days post-vaccination, but differences between the groups vaccinated and control groups were found at the early days post-vaccination. This results suggest that it is possible to prevent edwardsiellosis and streptococosis after a vaccination without affecting growth of olive flounder.

• New & Renewable Energy
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• v.16 no.2
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• pp.28-34
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• 2020

The South Korean government invested about 560 billion won in research and development in the wind power sector over 30 years from 1989 to 2019. In addition, the government has been setting up conditions for the country's wind industry to grow through various policies, including the RPS (Renewable Energy Portfolio Standard). As a result, the size of Korea's wind industry has grown to 1.1 trillion won in annual sales and there are 2,000 people working in the wind energy sector. While the domestic market is weak due to the small size of Korea and there are problems with the NIMBY, the government has continued to support technology developments and support market policies. Despite insufficient performance in overseas markets, the effect of the government is still significant on the growth of the wind industry. In particular, the government's R&D investment program, which focuses on enhancing companies' competitiveness, has spurred job creation in the wind industry and a stable research environment for researchers. In this study, we compared the differences between methods of investigating employment statistics in Korea and those of other countries. We also proposed effective investment measures for the government by analyzing the investment effects according to value chain and types of organization.

• Korean Journal of Plant Taxonomy
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• v.53 no.2
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• pp.157-165
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• 2023

Paraphlomis koreana (Lamiaceae) was newly named and added to Korean flora in 2014. Paraphlomis belongs to the tribe Paraphlomideae, along with Ajugoides and Matsumurella. However, a recent study has suggested that P. koreana is morphologically similar to Matsumurella chinensis, making them difficult to distinguish from each other. Therefore, we aimed to examine the phylogenetic placement of P. koreana within the tribe and compare its genetic relationship with M. chinensis. We sequenced an additional complete plastid genome for an individual of P. koreana and generated sequences of nuclear ribosomal (nr) DNA regions of internal and external transcribed spacers (ITS and ETS) for two individuals of P. koreana. Maximum likelihood analyses based on two nrDNA regions (ITS and ETS) and four plastid DNA markers (rpl16 intron, rpl32-trnL, rps16 intron, and trnL-F) covering 13 Paraphlomis species and M. chinensis were conducted. Phylogenetic analyses concordantly supported that P. koreana forms a monophyletic group with M. chinensis. Moreover, our study revealed that P. koreana includes nrDNA sequences of M. chinensis as minor intra-individual variants, suggesting that the genetic divergence between the two taxa is incomplete and may represent intraspecific variation rather than distinct species. In conclusion, our findings suggest that the independent species status of P. koreana within Paraphlomis should be reconsidered.

• Korean journal of applied entomology
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• v.32 no.3
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• pp.348-353
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• 1993

The fluctuation of insecticide resistance in the green peach aphid (GPA) in fields was investigated by caboxy1 esterase (CE) activity index analysis. Of the GP A Populations occurred on the red pepper seedlings, aphids in the untreaLed and treaLed with acephate plots showed 40 and 78 resistance percent (RP), respectively. Aphids in the untreated kale field showed the RP value 24 in July, contrast to 83 in October. Mean RPs of aphids from 18 localities were 50 + 14 in summer and B2+ 10 in late fall, indicating a seasonal fluctuation of Lhe CE activity.

• Molecules and Cells
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• v.28 no.4
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• pp.375-382
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• 2009

The 26S proteasome is a 2-MDa complex with a central role in protein turn over. The 26S proteasome is comprised of one 20S core particle and two 19S regulatory particles (RPs). The RPN12a protein, a non-ATPase subunit of the 19S RP, was previously shown to be involved in cytokinin signaling in Arabidopsis. To further investigate cellular roles of RPN12a, RNAi transgenic plants of RPN12a were constructed. As expected, the 35S:RNAi-RPN12a plants showed cytokinin signaling defective phenotypes, including abnormal formation of leaves and inflorescences. Furthermore, RNAi knock-down transgenic plants exhibited additional unique phenotypes, including concave and heart-shape cotyledons, triple cotyledons, irregular and clustered guard cells, and defects in phyllotaxy, all of which are typical for defective cytokinin signaling. We next examined the mRNA level of cytokinin signaling components, including type-A ARRs, type-B ARRs, and CRFs. The expression of type-A ARRs, encoding negative regulators of cytokinin signaling, was markedly reduced in 35S:RNAi-RPN12a transgenic plants relative to that in wild type plants, while type-B ARRs and CRFs were unaffected. Our results also indicate that in vivo stability of the ARR5 protein, a negative regulator of cytokinin signaling, is mediated by the 26S proteasome complex. These results suggest that RPN12a participates in feedback inhibitory mechanism of cytokinin signaling through modulation of the abundance of ARR5 protein in Arabidopsis.