http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
장유민,정해양 경희대학교 자연과학종합연구원 2003 자연과학논문집 Vol.9 No.2
광섬유의 편광모드 분산은 고속(>10Gbps) 광통신 시스템의 BER을 증가 시켜 성능을 저하시키는 중요한 요인으로 손꼽히고 있다. 광섬유를 진행하는 서로 수직한 두 개의 편광모드간의 군속도 차이에서 생기는 편광모드분산은 색분산에 비해 작은 값을 가지지만 그 크기가 임의로 변화하여 보상에 어려움이 있다. 이에 편광모드 분산의 원리를 이해하는 것이 앞으로 광통신 시스템의 성능을 향상하는 데에 필수적인 요소라 할 수 있다. 본 논문에서는 주파수도메인에서 편광모드분산의 원리를 소개하고 이를 바탕으로 Poincare arc 방법과 고정 검광자 방법 등과 같은 측정방법을 이용하여 100㎞의 단일 모드 광섬유의 편광모드분산을 측정 비교하였다. Polarization mode dispersion in fiber increases the bit-error rate of high speed(>l0Gbps) optical communication system and degrading the system performance. And the cause of polarization mode dispersion(PMD) is that the time delay between two orthogonal polarization modes having different group velocities in optical fibers. This PMD is more difficult to compensate the dispersion effects than CD case. We measured the PMD of single mode fiber spools up to l00km span using the simple wavelength scanning methods. Agreement between the Poincare arc method and the fixed analyzer method is also discussed.
1인 가구의 식생활 라이프스타일에 따른 외식 소비성향에 관한 연구
장유민,최규완,윤혜현 (사)한국조리학회 2024 한국조리학회지 Vol.30 No.4
. Currently, the number of single-person households in Korea is 7.5 million, accounting for 34.5% of all households. The consumption of single-person households, which account for the largest portion, was about 8% higher than the single-person households' consumption of two-person households, especially instant or processed foods. For this reason, we need to pay attention to the consumption of single-person households that occupy a large part but have strong consumption power. However, in order to grasp single-person households as a group, consumption expenditure patterns differ depending on age, economic status, lifestyle, etc., so in-depth research is needed. Therefore, the purpose of this study is to analyze the consumption behavior of eating out by classifying single-person households according to their dietary lifestyle. Accordingly, the survey was conducted for single-person households in their 20s to 50s, and 378 responses were used for analysis. As a result of the study, food-related lifestyle was classified into convenience-oriented, health-oriented, safety-oriented, trend-oriented and economy-oriented. These groups showed significant differences in the frequency of eating out, frequency of visiting eating out, frequency of delivery eating out, frequency of eating out alone, average monthly eating out cost, average delivery eating out cost, average visit eating out cost, average delivery eating out cost per meal, restaurant stay time, and frequency visit restaurnat. As such, there are many differences in considering single-person households as a group, and this study is of research significance in that it is divided into food-related lifestyles representing the characteristics of consumers. It is also significant that the survey was conducted on single-person households, which account for the largest portion of the current household, and can be used as basic marketing data in practice.