Li 도핑된 ZnSnO 박막 트랜지스터의 전기 및 광학적 특성에 대한 고속 중성자 조사의 영향

조인환,김찬중,전병혁,Cho, In-Hwan,Kim, Chan-Joong,Jun, Byung-Hyuk 한국재료학회 2020 한국재료학회지 Vol.30 No.3

The effects of fast neutron irradiation on the electrical and optical properties of Li (3 at%) doped ZnSnO (ZTO) thin films fabricated using a sol-gel process are investigated. From the results of Li-ZTO TFT characteristics according to change of neutron irradiation time, the saturation mobility is found to increase and threshold voltage values shift to a negative direction from 1,000 s neutron irradiation time. X-ray photoelectron spectroscopy analysis of the O 1s core level shows that the relative area of oxygen vacancies is almost unchanged with different irradiation times. From the results of band alignment, it is confirmed that, due to the increase of electron carrier concentration, the Fermi level (E_F) of the sample irradiated for 1,000 s is located at the position closest to the conduction band minimum. The increase in electron concentration is considered by looking at the shallow band edge state under the conduction band edge formed by fast neutron irradiation of more than 1,000 s.

HPLC-PAD를 이용한 교외지역 대기 중 Levoglucosan 계절 농도 변화 연구

조인환,박다정,권예슬,정혜선,배민석 한국대기환경학회 2015 한국대기환경학회 학술대회논문집 Vol.2015 No.11

인천국제공항 경쟁력 분석

조인환 천안대학교 - 기념논문집 Vol.30 No.2

InGaZnO 박막 트랜지스터의 전기 및 광학적 특성에 대한 전자빔 조사의 영향

조인환,박해웅,김찬중,전병혁,Cho, In-Hwan,Park, Hai-Woong,Kim, Chan-Joong,Jun, Byung-Hyuk 한국재료학회 2017 한국재료학회지 Vol.27 No.6

The effects of electron beam(EB) irradiation on the electrical and optical properties of InGaZnO(IGZO) thin films fabricated using a sol-gel process were investigated. As the EB dose increased, the electrical characteristic of the IGZO TFTs changed from semiconductor to conductor, and the threshold voltage values shifted to the negative direction. X-ray photoelectron spectroscopy analysis of the O 1s core level showed that the relative area of oxygen vacancies increased from 14.68 to 19.08 % as the EB dose increased from 0 to $1.5{\times}10^{16}electrons/cm^2$. In addition, spectroscopic ellipsometer analysis showed that the optical band gap varied from 3.39 to 3.46 eV with increasing EB dose. From the result of band alignment, it was confirmed that the Fermi level($E_F$) of the sample irradiated with $1.5{\times}10^{16}electrons/cm^2$ was located at the closest position to the conduction band minimum(CBM) due to the increase of electron carrier concentration.

중요도-실행도 분석을 통한 호텔 전자상거래 이용객 평가

조인환,문성호 국제e-비즈니스학회 2002 e-비즈니스 연구 Vol.3 No.1

Recently, the scale of E-commerce is increasing. many people predict that E-commerce will have great effect not only on our life but also marketing strategy. The objective of this research is to evaluate hotel e-commerce users using importance-performance analysis. A field survey was conducted and 218 samples were collected. The Results of this study are summarized as follows : First, the people who use the E-commerce actively aged from 20 to 39, worked as managerial, special officer, had high education and high income. According to this fact, many hotels have to set up the marketing strategies and fortify the scale and promotion toward characteristics indicated above. Second, it was indicated that satisfactory factors and important factors have the same means in E-commerce attributes. 'convenience' and 'variety' in E-commerce attributes have the high means, but 'E-commerce's safety' and 'exchange & repayment' have the low means. Hotels will have to try to reveal the merit having internet and get a continual attention toward safety system. The change of E-commerce market comes to great opportunity in hotel industries. Future research on E-commerce of hotel company needs to enlarge to more airlines. Thus, it is expected to help to set up the competitive strategies for hotel company. 최근 인터넷을 통한 전자상거래(EC; Electronic Commerce)가 급격히 활성화되고 있다. 전자상거래가 활기를 띠는 가장 큰 이유는 시간적, 공간적 제약 없이 고객확보가 용이하다는 점과 상거래상의 제반 비용을 크게 절감할 수 있다는 점이다. 따라서 인터넷 시장 환경에서 호텔들은 새로운 비즈니스 기회를 가져다 줄 수 있는 전자상거래 영업에 많은 노력을 기울이고 있다. 이런 점에서 본 연구에서는 중요도-실행도 분석을 통한 호텔상품 이용자들의 만족도를 분석하여 호텔기업들의 전자상거래 마케팅 측면에서 시사점을 얻고자 하였다.

실시간 대기 측정을 위한 미스트 발생기(MCN) 설계 및 성능 연구

조인환,박다정,권예슬,배민석 한국대기환경학회 2015 한국대기환경학회 학술대회논문집 Vol.2015 No.11

호텔 식음료부서 종사원의 자발적 조직행동, 자기유능감, 사회적 지원이 행동적 성과에 미치는 영향

조인환,유도재,전정아 한국외식경영학회 2010 외식경영연구 Vol.13 No.5

The purpose of this study is explored the determinant of behavioral performance focused on organizational citizenship behavior, self-efficacy & social support among hotel F&B employees. In order to achieve these purposes, we have studied the structural relations among organizational citizenship behavior, self-efficacy & social support to behavioral performance. The data were collected from 217 employees and analyzed using SPSS and AMOS. The results of hypothesis verification are as follows. First, employees' behavioral performance is influenced by organizational citizenship behavior. Second, employees'self-efficacy is influenced by organizational citizenship behavior. Third, employees'social support is partially influenced by organizational citizenship behavior. Forth,employees' behavioral performance is influenced by self-efficacy. Fifth, employees'behavioral performance is not influenced by social support. The result of this study will be helpful with the hotel industries which needs to establish marketing strategies.

저속 음성 코덱을 위한 효율적인 LSF 양자화기 설계

조인환,강상원 漢陽大學校 工學技術硏究所 1998 工學技術論文集 Vol.7 No.1

본 논문은 LPC계수의 효율적인 양자화기에 대한 연구로서, LSF 계수의 프레임간 높은 상관도와 예측 에러 신호의 기하학적 성질을 이용한 predictive pyramid vector quantization(PPVQ) 방식을 제안한다. LSF 계수의 예측을 위해 weighted distortion measure를 이용하여 설계한 4차 moving average(MA) 예측기틀 사용하였고, Laplacian 분포를 가지는 예측 에러 신호의 효율적인 양자화를 위해 pyramid VQ(PVQ)를 이용하였다. PPVQ는 적은 계산량으로 23 bits/frame에서 transparent한 성능을 가진다. 또한 PPVQ는 계산량이 적으며 코드북 저장을 위한 메모리를 전혀 필요치 않는다. In this paper, the predictive pyramid VQ(PPVQ) is proposed to quantize LSF parameters. The properties of the LSF parameters, whose prediction error signal is Laplacian and interframe correlation is high, are exploited. To predict the LSF parameters, 4th order moving average (MA) predictor is used, and to quantize the prediction error signal, the pyramid VQ (PVQ) is exploited. It is verified that the performance of PPVQ has the transparent quality at 23 bits/frame. PPVQ requires low complexity and does not need any memories for the codebook storage.

국내 CM과 PM 활성도 비교분석을 통한 PM 발전방안

조인환,강창욱 한국프로젝트경영학회 2012 한국프로젝트경영학회 학술대회 Vol.2012 No.1

단안 특발망막전막 환자에서의 융합과 억제

조인환,박운철,김성준,유나경,유형곤 대한안과학회 2020 대한안과학회지 Vol.61 No.7

Purpose: To investigate the presence of fusion and suppression in patients with unilateral idiopathic epiretinal membrane (ERM). Methods: Thirty-five patients with unilateral idiopathic ERM received a full ophthalmologic exam including best corrected visual acuity (BCVA). Patients were divided into suppression and non-suppression groups according to the results of 4 Prism Dioptre Base-out Test and Worth 4 Dot test. Age, symptoms, duration of ERM, BCVA, average M-chart score, results of Titmus test and optical coherence tomography parameters were compared between the two groups. Factors associated with suppression were also evaluated. Results: Eleven (31%) of 35 patients had suppression. The BCVA (0.18 ± 0.12 vs. 0.29 ± 0.12 p = 0.019) and stereopsis (2.25 ± 0.27 vs. 2.66 ± 0.62, p = 0.009) were significantly lower in the suppression group than the non-suppression group. Median age was older (63.21 ± 9.64 vs. 70.82 ± 6.80, p = 0.013) and duration of ERM (7.86 ± 3.69 vs. 18.54 ± 14.92 months, p = 0.004) was longer in the suppression group than the non-suppression group. Average M-chart score was higher in the suppression group. However, not all the patients suffered from metamorphopsia, including the suppression group when using binocular vision. Conclusions: Unilateral suppression is common in unilateral idiopathic ERM and influences the patient’s stereopsis. Suppression was significantly correlated with age, duration of symptoms and metamorphopsia. 목적: 단안 특발망막전막 환자에서 융합과 억제가 발생하는지 알아보았다. 대상과 방법: 단안 특발망막전막 환자 35명 35안을 대상으로 최대교정시력을 포함한 안과 검사를 시행하였다. 감각 융합 상태를 평가하기 위해 4프리즘바닥가쪽검사와 워스4등검사를 시행하고 억제가 있는 군(억제군)과 없는 군(비억제군)으로 나누어 각 군에서 나이, 증상, 기간, 최대교정시력, 평균 M-chart 점수, 티트무스검사와 빛간섭단층촬영 결과를 비교하였고 억제와 연관이 있는 인자를 찾아보았다. 결과: 35안 중 11안(31%)에서 망막전막이 있는 눈에 억제가 발생하였다. 억제군에서는 비억제군에 비해 교정시력(0.18 ± 0.12 vs. 0.29 ± 0.12, p=0.019)과 입체시(2.25 ± 0.27 vs. 2.66 ± 0.62, p=0.009)가 유의하게 더 낮았다. 또한 억제군의 평균 나이가 더 많았고(63.21 ± 9.64 vs. 70.82 ± 6.80세, p=0.013), 유병 기간이 더 길었다(7.86 ± 3.69 vs. 18.54 ± 14.92개월, p=0.004). 한편, 억제군의 단안 변형시 정도는 비억제군에 비해 유의하게 심했지만(0.43 ± 0.38 vs. 0.85 ± 0.56, p=0.020), 양안으로 M-chart 검사를 시행했을 경우는 억제가 있는 11안(31%) 모두에서 변형시를 느끼지 못했다. 결론: 이러한 결과는 단안 망막전막 환자에서 망막전막이 있는 눈에 억제가 흔하게 발생하고, 입체시에 영향을 미치며, 환자의 나이와 유병 기간, 변형시가 억제에 영향을 미침을 보여준다.