• JSTS:Journal of Semiconductor Technology and Science
• /
• 제6권1호
• /
• pp.52-58
• /
• 2006

Single-electron transistor (SET)-based logic cells and SET/FET hybrid integrated circuits have been fabricated on SOI chips. The input-output voltage transfer characteristic of the SET-based complementary logic cell shows an inverting behavior where the output voltage gain is estimated to be about 1.2 at 4.2K. The SET/FET output driver, consisting of one SET and three FETs, yields a high voltage gain of 13 and power amplification with a wide-range output window for driving next circuit. Finally, the SET/FET literal gate for a multi-valued logic cell, comprising of an SET, an FET and a constant-current load, displays a periodic voltage output of high/low level multiple switching with a swing as high as 200mV. The multiple switching functionality of all the fabricated logic circuits could be enhanced by utilizing a side gate incorporated to each SET component to enable the phase control of Coulomb oscillations, which is one of the unique characteristics of the SET-based logic circuits.

• International Journal of Advanced Culture Technology
• /
• 제8권2호
• /
• pp.1-5
• /
• 2020

As the world gradually advances to an aging society, the quality of human life is valued. Among them, 'quality of sleep' is very closely related to quality of life. Recently, Korea expanded health insurance coverage for "sleep disorders". Particularly, as the number of sleep multiple tests and prescriptions for sleep aids has increased rapidly, much attention has been focused on the related medical service environment. Therefore, this study looked at an in-depth interview of 11 hospitals to see what treatment delivery system is being established when the government applies health insurance for 'sleep disorders'. In conclusion, the organizations with the most average number of sleep polyp tests per day were found to have more sleep polyp labs (hardware) and more full-time specialists. Also, the polysomnography lab (hardware) and the specialist's full-time status (software) did not necessarily result in a "positive pressure regulator prescription" that can solve "sleep apnea" caused by "sleep ailments". Rather, it was found that the number of days of sleep multiple laboratories (hardware), the number of full-time specialists (software) or the specialty majors (software) had a greater impact. In particular, the higher the specialist's full-time personnel (software) index (=6.000), the higher the sleep-inducing agent prescription rate(=1.000), and the lower the specialist's full-time personnel (software) index (=1.000), the higher the sleep-inducer's prescription rate(= 0.010) Was low. In addition, even if the professional full-time personnel(software) index was the same (=1.000), the hospital type was lower as it was closer to the public hospital(=0.067) and higher at the specialized hospital (= 0.933). In the case of university hospitals, when the full-time specialists (software) are in the same condition (= 1.000), the frequency of use of the sleep laboratory (=1.000) and the sleep test rate (= 1.000) were all the same.

• 한국통신학회논문지
• /
• 제28권12C호
• /
• pp.1217-1224
• /
• 2003

본 논문에서는 직교 주파수 분할 다중 접속 방식(Orhogonal Frequency Division Multiple Acccss) 상향 링크에서의 간섭 완화를 위한 측부엽 억제 기법을 제안한다. 제안되는 측부엽 억제 기법은 특정 사용자와 그 외 사용자간의 서로 다른 주파수 오차에 의해 발생한 다중 접속 간섭을 완화시켜준다. 이러한 측부엽 억제 기법의 성능은 평균 신호대 간섭비와 비트 오율에 의해서 평가되었다. 모의 실험 결과에 의해서 제안되는 기법이 기존의 OFDMA 시스템과 비교하여 약 5∼10dB 가량의 신호대 간섭비 이득에 의한 성능을 향상시키는 것을 확인할 수 있으며, 특히 부대역 내의 모든 부반송파의 성능을 일정한 수준으로 유지시켜 준다. 측부엽 억제기를 구현하기 위해서는 사용자별로 할당되는 부대역 크기만큼의 메모리를 가지는 실수 검색 테이블과 부대역 크기만큼의 곱셈/덧셈 연산만이 요구되기 때문에 부가적으로 발생하는 시스템의 복잡도 증가가 거의 없다.

• 융합신호처리학회논문지
• /
• 제2권3호
• /
• pp.102-109
• /
• 2001

본 논문에서는 GF($P^{m}$ )상에서의 새로운 승산 알고리듬과 승산기 구성법을 나타내었다. 유한체 상에서의 두 원소에 대한 승산공식을 유도하였고 유도된 수식에 의해 승산기를 구성하였다. 적용예로 GF(3) 승산 모듈과 덧셈 모듈을 전류 모드 CMOS 기법을 적용하여 구현하였다. 이러한 모듈을 기본 모듈로 사용하여 GF(3$^{m}$ )승산기를 설계하였고 SPICE를 통하여 검증하였다. 제시된 승산기는 규칙적인 셀 구조를 사용하였고 단순히 규칙적인 내부 결선으로 구성된다. 따라서, 유한체 상에서 차수가 m 차로 증가하는 승산에 대해서도 간단히 확장이 가능하다.

• 한국직업건강간호학회지
• /
• 제20권1호
• /
• pp.1-13
• /
• 2011

Purpose: This study was conducted to compare the characteristics of organizational structure and occupational satisfaction among nurses in general hospital and small to medium-sized hospital and to investigate the affecting factors on their occupational satisfaction. Methods: The study was based on the cross-sectional descriptive survey. A self-report questionnaire was used to collect data from 343 nurses between June and July, 2010. Data were analyzed by ${\chi}^2$-test, t-test, ANOVA, Scheffe's test, Pearson's correlation coefficient, and multiple regression using the SPSS/WIN 14.0 program. Results: Hierarchical structure was dominant in general hospital whereas relationship was highly valued in small to medium-sized hospital. Occupational satisfaction was positively correlated with work environment built on relationship, innovation and tasks. Factors significantly influencing on occupational satisfaction in general hospital included innovative work environment, nurses' income and their health status ($R^2$=40.3%). For the small to medium-sized hospital, they included innovative work environment, satisfaction in life, tasks and professionalism ($R^2$=40.4%). Conclusion: Organizational structure, especially innovative work environment and relationship-oriented attitude had a significant influence on nurses' occupational satisfaction. Therefore, nursing administrators have to develop and consider organizational structure to improve occupational satisfaction.

• 복식문화연구
• /
• 제17권3호
• /
• pp.523-534
• /
• 2009

The purpose of this study is to categorize the dimensions of the visual evaluation of the costume details of the retro romantic fashion and to research on the costume details and the visual evaluation by evaluators' gender, age, and major, and on their preferences. Quantitative research were conducted for this study. Based on the pictures, 10 costume details were selected for the survey questions and data were collected. All 446 subjects who participated in this research were college students(males and females) residing in or near Seoul. Data were collected in September, 2008. The collected data were statistically analyzed using SPSS which included: factor analysis, Cronbach's $\alpha$ reliability analysis, three-way ANOVA, two-way ANOVA, one-way ANOVA, Duncan's multiple range tests, and the t-test. The results of visual evaluation of retro romantic fashion are as follows: First, as a result of the factor analysis of the costume detail evaluation, five factors including attractiveness, decorativeness, cuteness, retro, and femininity surfaced. Second, the gender difference in the results of the research revealed that women rated decorative, cute, retro, and feminine characteristics higher than men did. Third, there were significant interactive effects in attractiveness and femininity depending on costume details and evaluators' gender. Fourth, subjects majoring in fashion valued attractiveness and femininity of the stimulus over non-fashion majoring subjects. Fifth, there were significant differences in the preferences of costume details depending on gender.

• Transactions on Electrical and Electronic Materials
• /
• 제17권6호
• /
• pp.317-328
• /
• 2016

Over the past few decades, CMOS current comparators have been used in a wide range of applications, including analogue circuits, MVL (multiple-valued logic) circuits, and various electronic products. A current comparator is generally used in an ADC (analog-to-digital) converter of sensors and similar devices, and several techniques and approaches have been implemented to design the current comparator to improve performance. To this end, this paper presents a bibliographical survey of recently-published research on different current comparator topologies for low-power and high-speed applications. Moreover, several aspects of the CMOS current comparator are discussed regarding the design implementation, parameters, and performance comparison in terms of the power dissipation and operational speed. This review will serve as a comparative study and reference for researchers working on CMOS current comparators in low-power and high-speed applications.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2001년도 춘계학술대회논문집C
• /
• pp.537-542
• /
• 2001

In recent engineering, the designer has become more and more dependent on computer simulation. But defining exact model using computer simulation is too expensive and time consuming in the complicate systems. Thus, designers often use approximation models, which express the relation between design variables and response variables. These models are called metamodel. In this paper, we introduce one of the metamodel, named Kriging. This model employs an interpolation scheme and is developed in the fields of spatial statistics and geostatistics. This class of interpolating model has flexibility to model response data with multiple local extreme. By reason of this multi modality, we can't use any gradient-based optimization algorithm to find global extreme value of this model. Thus we have to introduce global optimization algorithm. To do this, we introduce DE(Differential Evolution). DE algorithm is developed by Ken Price and Rainer Storn, and it has recently proven to be an efficient method for optimizing real-valued multi-modal objective functions. This algorithm is similar to GA(Genetic Algorithm) in populating points, crossing over, and mutating. But it introduces vector concept in populating process. So it is very simple and easy to use. Finally, we show how we determine Kriging metamodel and find global extreme value through two mathematical examples.

• 한국통신학회논문지
• /
• 제29권7C호
• /
• pp.937-945
• /
• 2004

잡음 제거에 사용되는 이진 결정 모델은 단지 이분적인 구분만을 수행하기 때문에 잡음에 대한 신호의 정확한 비율을 측정하기 어려운 단점이 있다. 이러한 단점을 보완하기 위하여 복잡한 통계 모델 및 다운샘플링이 되지 않은 웨이블릿 변환을 사용하는 것이 일반적이다. 본 논문에서는 잡음 영상에서 잡음의 정도를 측정할 수 있는 다수준 결정 모델을 이용한 잡음 제거 방법을 제안한다. 제안 방법은 잡음에 대한 신호의 비율을 다수준 값의 형태로 계산할 수 있기 때문에 직교 웨이블릿 변환으로 좋은 잡음 제거 성능을 나타낼 수 있다. 모의실험 결과를 통하여 본 논문의 방법이 직교 웨이블릿 변환을 사용한 최신의 잡음 제거 방법보다 PSNR 측면에서 평균적으로 0.ldB 정도 우수한 성능을 나타낸다는 것을 보여준다.

• 제어로봇시스템학회논문지
• /
• 제18권4호
• /
• pp.375-383
• /
• 2012

Together with the GPS-based approach, geolocation through mobile communication networks is a key technology for location-based service. Since the Mobile WiMAX system is considered as a candidate for fourth-generation mobile systems, it is important to investigate its location capability. The geolocation of Mobile WiMAX can be realized when the preamble symbols in the down-link channel are appropriately used for a TDOA (Time-Difference-of-Arrival) approach. However, the cellular structure of Mobile WiMAX inevitably generates co-channel interference, and it is difficult for the mobile terminal to acquire distance measurements from multiple base stations. Therefore, for geolocation via multilateration using the Mobile WiMAX network, it is very important to increase hearability. This paper proposes a geolocation method for Mobile WiMAX which employs interference cancellation and preamble signal overlapping for the enhancement of hearability. A novel interference cancellation strategy for complex-valued Mobile WiMAX signals is presented which has an iterative structure. Simulation results show that the proposed geolocation method provides the user's position with an accuracy of less than 20 m through the Mobile WiMAX cellular network if there is no multi-path or NLOS (None-Line-of-Sight).