• Title/Summary/Keyword: Period shift

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Laser sensor wavelength interrogation using a long-period fiber grating (장주기 격자를 이용한 광섬유 레이저센서의 파장변화 측정)

  • Song, Min-Ho;Lee, Sang-Bae;Choi, Sang-Sam;Nam, Hui;Lee, Byoung-Ho
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.34D no.12
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    • pp.83-88
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    • 1997
  • We present a fiber laser sensor that uses a fiber grating as a strain sensor head and an end-reflector of the laser cavity. A passive wavelength. The long-period grating band-rejection filter showed a wide usable filter wavelength range of about 25 nm, and the intensity of transmitted light increased by 16% for 1nm sensor wavelength shift in trhe measurement range.

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High-Resolution Interrogation Technique for Fiber Bragg crating Sensor Using Long-Period Fiber Grating Pair and Erbium-Doped fiber

  • Jung, Jae-Hoon;Lee, Yong-Wook;Lee, Byoung-Ho
    • Journal of the Optical Society of Korea
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    • v.6 no.1
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    • pp.5-12
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    • 2002
  • A novel interrogation scheme to detect fine Bragg wavelength shift using a long period fiber grating pair with erbium-doped fiber inserted between the two gratings is reported. The technique is shown to feature high resolution and much more immunity to temperature perturbation compared to the conventioned Mach-Zehnder interferometer demodulation system. For quasi-static strain measurement, this approach provides high wavelength resolution of 0.05 pm that corresponds to 41.7 ne in strain and $3.8 $\times$ 10^{-3}$$^{\circ}C$ in temperature. This interrogation system is also employed in dynamic measurement to obtain the minimum detectable strain perturbation of ~ 8.76 ne/H $z^{{\frac}{1}{2}}$ at 100 Hz. Moreover, this interrogation system has prominent thermal stability. This thermal stability comes from the fact that two arms of the interferometer, the core and cladding in erbium-doped fiber, are exposed to nearly the same environment .

ON A CHARACTERIZATION OF T-FUNCTIONS WITH ONE CYCLE PROPERTY

  • Rhee, Min Surp
    • Journal of the Chungcheong Mathematical Society
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    • v.21 no.2
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    • pp.259-268
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    • 2008
  • To the design of secret key, there are two types of basic approaches called the tame approach and the wild approach. In the tame approach we try to use only simple primitives such as linear feedback shift registers and to prove mathematical theorems about their cryptographic properties. In the wild approach we try to use crazy compositions of operations which mix a variety of domains in a nonlinear and nonalgebraic way. There are several papers which try to bridge this gap by considering semi-wild constructions. A T-function on n-bit words plays an important role in semi-wild constructions. In this paper we study the invertibility and the period of some T-functions. Especially we characterize some polynomials which has a single cycle property.

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Evaluation of local and global ductility relationships for seismic assessment of regular masonry-infilled reinforced concrete frames using a coefficient-based method

  • Su, R.K.L.;Tang, T.O.;Lee, C.L.
    • Earthquakes and Structures
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    • v.5 no.1
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    • pp.1-22
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    • 2013
  • Soft storey failure mechanism is a common collapse mode for masonry-infilled (MI) reinforced concrete (RC) buildings subjected to severe earthquakes. Simple analytical equations correlating global with local ductility demands are derived from pushover (PO) analyses for seismic assessments of regular MI RC frames, considering the critical interstorey drift ratio, number of storeys and lateral loading configurations. The reliability of the equations is investigated using incremental dynamic analyses for MI RC frames of up to 7 storeys. Using the analytical ductility relationship and a coefficient-based method (CBM), the response spectral accelerations and period shift factors of low-rise MI RC frames are computed. The results are verified through published shake table test results. In general applications, the analytical ductility relationships thus derived can be used to bypass the onerous PO analysis while accurately predicting the local ductility demands for seismic assessment of regular MI RC frames.

Aesthetic Characteristics of Western Women's Costumes on Artistic Paradigm Shifts and Modern Expression in Fashion (예술적 패러다임 전환기에 나타난 서양 여성 복식의 미적 특성과 현대적 표현)

  • Jun, Yuh Sun;Kim, Young Sam
    • Fashion & Textile Research Journal
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    • v.16 no.6
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    • pp.835-848
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    • 2014
  • This study investigated the relationship between inner characteristics manifested through the characteristics of artistic styles and formativeness manifested through external expressions of architectural styles in the early Medieval Period and early Renaissance Period. The method applied to this study is as follows. First, a historical document research was conducted centering on academic theses, related books, and academic databases; in addition, a case study identified the aesthetic characteristics of women's clothes. The conclusion of this study is as follows. First, the following is the analysis of the relationship between the artistic mode and architectural formativeness in the early Medieval Period and early Renaissance Period that represent a turning point in artistic paradigms. Second, the inner characteristics and eclecticism of the artistic mode literally appear in the formativeness of architectural style in the early Medieval Period, and the eclecticism in the architectural style appears to be expressed through a combination with new styles based on the application of the retro mode such as the eclectic adoption of cultural styles of various regions based on the tradition and technology of ancient Rome. Third, the trend of the aesthetic characteristics commonly appear in the modern style of expression related to the aesthetic characteristics of western women's clothes in the early Medieval Period; in addition, the early Renaissance Period was analyzed as decorativeness and respectively manipulability.

A Study on The Etiology of Wu You-ke(吳又可)'s Epidemic(溫疫) Theory (오우가(吳又可) 온역학설(溫疫學說)의 병인관(病因觀)에 대한 연구)

  • Eun, Seok-Min
    • Journal of Korean Medical classics
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    • v.20 no.4
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    • pp.251-265
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    • 2007
  • This study is a research on the etiology in Wu Youke's wenyi theory. In regard to the etiology of epidemic disease that had been spread on a very large scale at that time, Wu Youke denied the traditional theory which urged the irregular change of climate as the cause of epidemic disease, and proposed the concept of 'zaqi' which was considered by him to be something that could be the real cause of epidemic disease. And He treated the wenyi disease as something that has the same meaning with wenbing, so his concept on wenbing was basically the thing that treats 'zaqi' as the fundamental cause of wenbing and treats the concept of 'wen(溫)' as an environmental cause that could help activate the virulence of 'zaqi'. Such concept like this was the thing somewhat different from the traditional etiological theory that considers the change of climate as the principal cause of waigan(外感)-disease, and it must for the most part have been originated from the experience of Wu Youke himself. But this study, in contrast, based on the thing he denied the traditional theory on the irregular change of climate, has been done in the point of view that fundamental concept of his wenyi theory such as 'zaqi' was not only originated from his clinical experience but also from the influence of paradigm shift in the natural philosophy of that time. There had been so much change in cosmology and natural philosophy from the fundamental basis at that time, and the the most principal concept of it was that there always exists irregular faces in the change of nature. Such concept like this got into its stride from about 17th century, and it was expressed in the form of the severe criticism against the traditional natural philosophy. In regard to this, this study has outlined the academic thought of the leading scholars who made a significant progress in such a paradigm shift, and it includes the scholars like Wang Tingxiang, Wang Fuzhi, Hu Wei, Huang Zongxi, who played their role in the time of the latter period of Ming dynasty and the former period of Qing dynasty.

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The Influence of Workplace Violence on Work-related Anxiety and Depression Experience among Korean Employees (한국 근로자의 업무관련 불안감 및 우울감 경험에 대한 직장폭력의 영향)

  • Choi, Eun-Sook;Jung, Hye-Sun;Kim, Su-Hyun;Park, Hyun-Ju
    • Journal of Korean Academy of Nursing
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    • v.40 no.5
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    • pp.650-661
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    • 2010
  • Purpose: Work-related anxiety and depression are frequent work-related mental health problems. In this study the relationship between workplace violence and work-related anxiety and/or depression among Korean employees was evaluated. Methods: Data were obtained from the Korean Working Condition Survey of 2006. Participants were 9,094 Korean workers aged 15-64 yr. Multiple logistic regression using SAS version 9.1 was used. Results: The incidence of work-related anxiety, work-related depression and workplace violence were 4.5%, 3.5%, and 1.8% respectively. When personal and occupational risk factors were adjusted, workplace violence was significantly associated with work-related anxiety and depression (OR for anxiety: 4.07, CI: 2.62-6.34; OR for depression: 4.60, CI: 2.92-7.25). Work-related anxiety was significantly related to type of employment, working period at present workplace, work time, shift work, job demand, and social support from superiors. Factors influencing work-related depression were gender, education, alcohol consumption, company size, type of employment, working period at present workplace, work time, shift work, and job demand. Conclusion: To promote psychological health in workers there is a need to develop work-related anxiety and depression prevention programs and to decrease in workplace violence. In developing these programs, consideration should be given to personal factors, working conditions, and psychosocial working environments.

Labor Market Dynamics and Regional Economic Development in Post-Reform China: Implications for Understanding Changing Regional Inequality (경제개혁이후 중국의 노동시장 역동성과 지역경제발전 : 지역격차변화 이해에 대한 함의)

  • 이원호
    • Journal of the Economic Geographical Society of Korea
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    • v.3 no.2
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    • pp.23-42
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    • 2000
  • This study is to investigate spatial patterns of urban labor market growth driven by marketization process and its implication for understanding regional uneven development in post-reform China. Using a shift share analysis, it shows that the geography of employment growth in China's industrial labor market has closely interacted with the space economy of industrial output, which in turn indicates a deepening of economic reform. By decomposing net employment growth into output and productivity effects, it is shown that the non-state sector holds rapid growth of both output and productivity and contributes to net employment growth through positive net shifts. On the contrary, this study also presents that the state sector with relative decrease in output and productivity holds employment decline effects during the reform period. Since there is a significant spatial dimension for the trend above, it is contended that labor market dynamics together with space economy of industrial production play an important role in determining regional patterns of economic development. In addition, through situating this investigation in the context of structural and institutional changes in the reform period, our understanding of regional patterns of labor market growth will be much furthered.

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Management of Aesthetic intentions in Urban Design -Artworks in Urban Public Space-

  • Takeda, Naoki;Yagi, Kentaro
    • Journal of the Korean Institute of Landscape Architecture International Edition
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    • no.1
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    • pp.167-175
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    • 2001
  • After World War II, Japan experienced a great political and social shift, which brought a concern of emerging public landscape in urban development. This paper analyses the management of the aesthetic intentions in urban design effort. We reviewed the development of various public installation of artworks concerning urban landscape aesthetics through its administrative process in chronological order. The monuments during the first decade marked a shift in emphasis from the militarism of the pre-war and wartime period to one of peace. However, some of the monuments and sculptures are not immune to controversy. This became an issue that could no be ignored by public officials whose responsibility was to place the sculptures while maintaining sensitivity to public opinion. As public administrators began to consider the possibility that sculptures may contribute to improving public amenities, the contextual concepts were basically ignored. Some of the programs in 1970s began to show more respect to the context, while other programs in this period expressed more interest in educational aspects of sculptures in the public spaces. Urban development projects also seek to introduce artworks integrated to their urban design concepts in 1990s. Generally, the administrators responsible for these programs were rarely trained in any relative field study other than public administration. Installing sculptures tended to be considered as part of public works projects on the level of urban planning and construction. The general public is basically removed from participating in the critical decisions that actually impact their lives in relation to the artworks. In conclusion, public art in japan has unique social and historic background both in its advantages and disadvantages. Issues pertaining to art in public spaces have evolved over the decades as the term "sculpture pollution" began to appear by the mid 1990s. most of the problems originated in either the lack of monumentality, contextual consideration, quality, or public participation. From another point of view, these programs played great roll in the development of modern Japanese sculpture and patronizing process, and the creation of new urban landscape with aesthetic value. In this sense, they must be considered as successful and noteworthy examples of cultural administration and urban design policy.

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Age-period-cohort Analysis of Healthy Lifestyle Behaviors Using the National Health and Nutrition Survey in Japan

  • Okui, Tasuku
    • Journal of Preventive Medicine and Public Health
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    • v.53 no.6
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    • pp.409-418
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    • 2020
  • Objectives: This study conducted an age-period-cohort (APC) analysis of trends in healthy lifestyle behaviors in Japan. Methods: We used National Health and Nutrition Survey data on salt intake and prevalence of smoking, drinking, and physical activity between 1995 and 2018 in Japan. Age groups were defined from 20 years to 69 years old in 10-year increments. Cohorts were defined for each age group of each year with a 1-year shift, and cohorts born in 1926-1935 (first cohort) until 1989-1998 (last cohort) were examined. We conducted a Bayesian APC analysis, calculating estimated values for each behavior by age group, period, and cohort. Results: Estimated salt intake decreased from cohorts born in the 1930s to the 1960s, but increased thereafter in both genders, and the magnitude of increase was larger for men. Estimated smoking prevalence increased in the cohorts starting from the 1930s for men and the 1940s for women, and then decreased starting in the cohorts born in the 1970s for both genders. Although estimated drinking prevalence decreased starting in the cohorts born in approximately 1960 for men, for women it increased until the cohorts born in approximately 1970. Estimated physical activity prevalence decreased starting in the cohorts born in the 1940s in both genders, but the magnitude of decrease was larger for women. Conclusions: Trends in cohort effects differed by gender, which might be related to changes in the social environment for women. Improvements in dietary and exercise habits are required in more recently born cohorts of both genders.