Electrical, Thermal, and Thermoelectric Transport Properties of Se-doped Polycrystalline Re2Te5

Se Woong Lee,Okmin Park,Hyun-Sik Kim,Won-Seon Seo,Sang-il Kim 대한금속·재료학회 2022 대한금속·재료학회지 Vol.60 No.12

Re2Te5 is considered a potential thermoelectric material because of its intrinsically low thermalconductivity, due to its complex crystal structure. Herein, a series of Se-doped Re2Te5 (Re2Te5-xSex, x = 0, 0.2,1, and 2) samples were synthesized, and their electrical and thermal transport properties were investigated. Pure orthorhombic Re2Te5 phases were successfully synthesized without any impurities for all compositions,and the continuous decrease in the calculated lattice parameters confirmed the substitution of Se atoms atthe Te sites. A maximum power factor of 0.135 mW/mK2was achieved for the sample with x = 0.2 at 880 K,mainly due to the increase in carrier concentration and electrical conductivity. The lattice thermalconductivity significantly decreased for all doped samples, which was attributed to the point defect phononscattering caused by Se doping. The thermoelectric figure of merit, zT reached a maximum value of 0.20 at880 K for Re2Te4.8Se0.2 (x = 0.2) sample, which was approximately 22% higher than that of the pristine Re2Te5sample. The weighted mobility, quality factor, and expected zT were calculated to evaluate the optimizationof the power factor and zT.

전기장 인가에 따른 DNA 신장에 관한 AFM 연구

박진영,한성웅,손세영,송성훈,김종민,Ohtani, Toshio,Muramatsu, Hiroshi,장상목 한국화학공학회 2002 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.40 No.1

본 연구에서는 마이카 표면상에서 전기장에 의한 극히 낮은 농도의 DNA 신장에 대한 효율적인 방법론을 제시하였다. 전기장에 의한 DNA 신장을 AFM형상으로 분석한 결과, DNA 농도범위가 약 57×10 exp(-3)ng/mL-57×10 exp(-6)ng/mL일 때 매우 잘 적용되며, 신장된 DNA는 두 전극 중앙에 존재하였다. 또한, 일반 마이카, Mg^2+ 처리된 마이카, 그리고 AP-마이카 표면들에 대한 신장 효율의 차를 기술하였다. 동일한 실험조건 하에서 AP-마이카의 표면이 가장 좋은 효율의 DNA 신장 결과를 나타내었다. An effective method of DNA stretching using electric field on mica surface was proposed for extremely low solution concentration of DNA. DNA stretching based on electric field was observed by AFM and well applied on the concentration range from 57×10 exp(-3)ng/mL to 57×10 exp(-6)ng/mL. Stretched DNA existed in the middle of two electrodes. The difference in stretching efficiency for the different surfaces of bare mica, Mg^2+ soaked mica and AP-mica was discussed. The best performance of stretching was found from the surface of AP-mica under the same experimental condition.

구륜 이동 로봇의 위치추정을 위한 퍼지-유전자 제어기

한철웅,김종수,류평,오금곤,박세승 조선대학교 전자정보통신연구소 2000 電子情報通信硏究所論文誌 Vol.3 No.1

지능제어 기법중 하나인 퍼지-유전자 알고리즘은 매개변수 불확실성을 갖는 시스템을 제어하기 위한 새로운 제어 기법으로 사용되어지고 있다. 유전자 알고리즘에서, 돌연변이율은 국부적 최소화에 수렴하는 것을 방지하기 위하여 크게 설정하여야만 하지만, 전역 수렴 속도가 감소하는 문제점을 가지고 있다. 이러한 문제점을 개선하기 위하여 퍼지 논리와 유전자 알고리즘을 사용하여 제어기를 설계한다. 본 논문에서는 구륜이동 로봇의 목적궤적을 추적할 수 있는 제어기 설계를 제안한다. 제안된 제어기의 유용성은 모의실험을 통하여 보인다. Genetic algorithms, one of intelligent control methods, is used as new control approach to control the system including the parameter uncertainties In the genetic algorithm, the mutation rate must be set to high to prevent the convergence to local minimum, but it has the problem that the global convergence speed is decreased To enhance this problem, we design the controller by using the fuzzy logic and the genetic algorithm In this paper, we propose the controller design to track to the desired trajectory of the wheeled-mobile robot The validity of the proposed controller is showed through the simulation.

Lidocaine으로 Retrobulbar block時 發生한 過敏反應 1例

金世煥,朴辰雄,金炳權 대한마취과학회 1977 Korean Journal of Anesthesiology Vol.10 No.3

This report shows a fatal hyperergy occurring during retrobulbar block using lidocaine on a 42 years old male patient. When we injected 60㎎ of lidocaine into the retrobulbar space, following signs were noticed in one minute: hypertension, convulsion, dyspnea and loss of consciousness. In addition to the above symptoms, cardiac arrest developed in 2∼3 minutes and did not respond to any resuscitative effort. It is considered that 60㎎ of lidocaine for retrobulbar block can induce hyperergy and cardiac arrest. The clinical picture and treatment of such reaction is discussed with particular attention to the importance of close observation of all anesthetic patients whether under general or local anesthesia.

결과지식의 정확성이 운동학습 효과에 미치는 영향

이세웅,박장평 江原大學校附設 體育科學硏究所 1992 江原大學校附設體育科學硏究所論文集 Vol.- No.17

The purpose of this study was to find out if there is any effect of the precision of knowledge of results on motor learning. Total twenty-four female students of middle school were used as subjects and divided into two groups, Quantitative KR and Qualitative KR. Each group consisted of twelve subject. The task of experiment was Liner Positioning task. The knowledge of results interval was fixed as immediately and post-knowledge of results in-terval was fixed as three seconds. As the results of experiment, the conclusions were made as follows : 1) Both quantitative KR and qualitative KR significantly have an effect on results of early performance. 2) In retention test to examine the ability of motor memory which is result of motor learning, quantivtative KR group is more excellent than Qualitative KR group and the effects are consistent.

유압굴삭기의 부하감지회로에 대한 연구

趙勝鎬,安世雄,朴鐘沅 弘益大學校 科學技術硏究所 1996 科學技術硏究論文集 Vol.7 No.1

In this paper theoretical analyses are performed on the load sensing system of excavator and databases are constructed for the valve opening areas, pump horce power control and for load sensing regulator. For hydraulic components modularized modelings are carried out, which is expected to be utilized for software development of fluid power system. Through simulation an information of any point in fluid power circuit can be obtained.

Electrical, Thermal, and Thermoelectric Transport Properties of Co-Doped n-type Cu0.008Bi2Te2.6Se0.4 Polycrystalline Alloys

Okmin Park,TaeWan Kim,Minsu Heo,Sang Jeong Park,Se Woong Lee,Hyun Kyu Cho,Sang-il Kim 대한금속·재료학회 2023 대한금속·재료학회지 Vol.61 No.3

Bi2Te3-based alloys have been extensively studied as thermoelectric materials near roomtemperature. In this study, the electrical, thermal, and thermoelectric transport properties of a series of Codopedn-type Cu0.008Bi2Te2.6Se0.4 polycrystalline alloys (Cu0.008Bi2−xCoxTe2.6Se0.4, x = 0, 0.03, 0.06, 0.09 and 0.12)are investigated. The electrical conductivity of the Cu0.008Bi1.97Co0.03Te2.6Se0.4 (x = 0.03) sample wassignificantly enhanced, by 34%, to 1199 S/cm compared to 793 S/cm of the pristine Cu0.008Bi2Te2.6Se0.4 (x = 0)sample at 300 K, and gradually decreased to 906 S/cm for x = 0.12 upon further doping. Power factors of theCo-doped samples decreased compared to the 3.26 mW/mK2 of the pristine Cu0.008Bi2Te2.6Se0.4 sample at 300K. Meanwhile, the power factor of the Cu0.008Bi1.97Co0.03Te2.6Se0.4 (x = 0.03) sample became higher at 520 K. The lattice thermal conductivities of the Co-doped samples decreased due to additional point defect phononscattering by the Co dopant. Consequently, the zT for the Cu0.008Bi1.97Co0.03Te2.6Se0.4 alloy at 520 K was 0.83,which is approximately 15% larger than that of pristine Cu0.008Bi2Te2.6Se0.4, while the zT of the Cu dopedsamples at 300 K was smaller than that of the pristine Cu0.008Bi2Te2.6Se0.4 sample. Electrical transportproperties of the Co-doped Cu0.008Bi2−xCoxTe2.6Se0.4 samples were analyzed by experimental phenomenologicalparameters, including the density-of-state, effective mass, weighted mobility, and quality factor.

Thermoelectric Properties of Cu-added Polycrystalline Bi2O2Se Oxyselenide

Si-young Bae,Se Woong Lee,Hyun-Sik Kim,Okmin Park,Hyunjin Park,Won-Seon Seo,Sang-il Kim 대한금속·재료학회 2022 대한금속·재료학회지 Vol.60 No.12

Bi2O2Se oxyselenide has been actively studied as a potential n-type thermoelectric material becauseof its intrinsically low thermal conductivity and high Seebeck coefficient (S). However, Bi2O2Se has very lowelectrical conductivity (σ), resulting in relatively poor thermoelectric performance. Herein, we investigate theeffect of Cu addition on the electrical and thermal transport of n-type polycrystalline Bi2O2Se. A series ofCuxBi2O2Se (x = 0, 0.0025, 0.005, and 0.0075) polycrystalline samples were synthesized by a conventional solid state reaction. Tetragonal Bi2O2Se was successfully synthesized, and its lattice parameters graduallydecreased with the addition of Cu. Further, σ decreased and the magnitude of S increased with increasingCu content, according to the trade-off relationship between these parameters. Consequently, a maximumpower factor of 0.106 mW m-1 K-2 was achieved for the sample with x = 0.0025 at 300 K, owing to the increasein the magnitude of S. The Hall carrier concentration decreased exponentially with the addition of Cu, whichis mainly attributed to the possible enlargement of the band gap of the Cu-added samples. The lattice thermalconductivity decreased with increasing x, which was attributed to point-defect phonon scattering via Cuaddition. Therefore, a maximum zT of 0.222 was obtained at 790 K for the Cu0.0025Bi2O2Se (x = 0.0025) sample,which was approximately 8% higher than that of the pristine Bi2O2Se sample.

Session 1. 최근 국제적 이슈가 되고 있는 호흡기 인수공통전염병: Recent Hot Issues in Respiratory : Sl-3 ; Specific Mutations in the Hemagglutinin Increase Potential of a H7N9 Vaccine Virus

( Se Hee Park ),( Jin Il Kim ),( Ilseob Lee ),( Joon Yong Bae ),( Min Woong Hwang ),( Dong Hwan Kim ),( Seok Il Jang ),( Hye Jin Kim ),( Mee Sook Park ),( Young Ki Choi ),박만성 ( Man Seong Park ) 대한인수공통전염병학회 2014 창립총회 및 학술대회 초록집 Vol.2014 No.1

Since March 2013, avian influenza H7N9 virus has caused human infections with resulting in an estimated 30% case fatality rate. Although there has been no evidence of sustained human-to-human transmission, effective medical responses and preparedness should be implemented including developing vaccines. Using the hemagglutinin (HA) of A/Anhui/1/2013, a prototype virus recommended for the H7N9 vaccine development by the World Health Organization, we investigated the effects of HA glycosylation on the growth kinetics and immunogenicity of recombinant viruses that generated in the backbone of a 2009 pandemic H1N1 virus. Glycosylation at HA residue increased viral growths both in cultured cells and in fertile chicken eggs whereas deglycosylation at HA residue decreased them all. When HA glycosites were utilized together, the virus exhibited the greatest replication property. In the hemagglutinin inhibition assay using guinea pig antisera raised against each virus. These antisera showed 1.75- to 4-fold increased immunogenicity across all of the tested viruses. Considered all, these results suggest that specific HA mutation can increase potential of a H7N9 vaccine virus by enhancing growth and immune properties.

Gain of a New Exon by a Lineage-Specific Alu Element-Integration Event in the BCS1L Gene during Primate Evolution

Park, Sang-Je,Kim, Young-Hyun,Lee, Sang-Rae,Choe, Se-Hee,Kim, Myung-Jin,Kim, Sun-Uk,Kim, Ji-Su,Sim, Bo-Woong,Song, Bong-Seok,Jeong, Kang-Jin,Jin, Yeung-Bae,Lee, Youngjeon,Park, Young-Ho,Park, Young Il Korean Society for Molecular and Cellular Biology 2015 Molecules and cells Vol.38 No.11

BCS1L gene encodes mitochondrial protein and is a member of conserved AAA protein family. This gene is involved in the incorporation of Rieske FeS and Qcr10p into complex III of respiratory chain. In our previous study, AluYRa2-derived alternative transcript in rhesus monkey genome was identified. However, this transcript has not been reported in human genome. In present study, we conducted evolutionary analysis of AluYRa2-exonized transcript with various primate genomic DNAs and cDNAs from humans, rhesus monkeys, and crabeating monkeys. Remarkably, our results show that AluYRa2 element has only been integrated into genomes of Macaca species. This Macaca lineage-specific integration of AluYRa2 element led to exonization event in the first intron region of BCS1L gene by producing a conserved 3' splice site. Intriguingly, in rhesus and crabeating monkeys, more diverse transcript variants by alternative splicing (AS) events, including exon skipping and different 5' splice sites from humans, were identified. Alignment of amino acid sequences revealed that AluYRa2-exonized transcript has short N-terminal peptides. Therefore, AS events play a major role in the generation of various transcripts and proteins during primate evolution. In particular, lineage-specific integration of Alu elements and species-specific Alu-derived exonization events could be important sources of gene diversification in primates.