• Title/Summary/Keyword: Period Characterized

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Bilinear elastodynamical models of cracked concrete beams

  • Pandey, Umesh Kumar;Benipal, Gurmail S.
    • Structural Engineering and Mechanics
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    • v.39 no.4
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    • pp.465-498
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    • 2011
  • Concrete structures are generally cracked in flexural tension at working loads. Concrete beams with asymmetric section details and crack patterns exhibit different flexural rigidity depending upon the sense of the applied flexural moment. In this paper, three different models, having the same natural period, of such SDOF bilinear dynamical systems have been proposed. The Model-I and Model-II have constant damping coefficient, but the latter is characterized by two stiffness coefficients depending upon the sense of vibration amplitude. The Model-III, additionally, has two damping coefficients as well. In this paper, the dynamical response of Model-III to sinusoidal loading has been investigated and compared with that of Model-II studied earlier. It has been found that Model-III exhibits regular and irregular sub-harmonics, jump phenomena and strong sensitivity to initial conditions, forcing frequency, system period as well as the sense of peak sinusoidal force. The constant sustained load has been found to affect the natural period of the dynamical system. The predictions of Model-I have been compared with those of the approximate linear model adopted in present practice. The behaviour exhibited by different models of the SDOF cracked elastic concrete structures under working loads and the theoretical and practical implications of the approach followed have been critically evaluated.

Literature Review on Adolescent Runaways (청소년 가출에 관한 이론적 고찰)

  • Jung, Woon-Sook;Park, Shin-Ae
    • Research in Community and Public Health Nursing
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    • v.12 no.1
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    • pp.105-114
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    • 2001
  • It was orginally thought that runaway adolescents needed to improve their ability to cope with personal problems based on their own understanding of them. As a result we exchanged theoretical background on the matter as follows: 1. Generally, adolescency is a transitional period from childhood to adulthood and characterized by a dramatic conversion period with unique phenomena relative to other periods. Futhermore, it is the key transitional moment in the development of an adult personality. 2, Runaway adolescents are defined as 'adolescents who leave impulsively or intentionally their homes without permission of their parents for at least 24 hours.' 3. The reasons for this behavior are generally regarded as complex, interdependent and dynamic including a cast-away factor. seducing factors, and other action-provoking factors. There is also another view to explain the adolescent run-away as a combination of personal. domestic, academic, peer, or socal factors. 4. We found that adolescent runaways have different attitudes dependent on the reasons and procedures of runaways, lifestyles of adolescents. and results of their runaway experience. In conclusion, runaway adolescents are in a very important period in their development and growth of bodies and minds, but are in a great crisis for various complex reasons. Therefore, we propose that nursing should provide effective nursing interventions to improve the ability of the runaway adolescents address theses problems by themselves.

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Sensing Characteristics of Uncoated Double Cladding Long-period Fiber Grating Based on Mode Transition and Dual-peak Resonance

  • Zhou, Yuan;Gu, Zheng Tian;Ling, Qiang
    • Current Optics and Photonics
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    • v.5 no.3
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    • pp.243-249
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    • 2021
  • In this paper, the sensing characteristics of a double cladding fiber (DCF) long-period fiber grating (LPFG) to the surrounding refractive index (SRI) are studied. The outer cladding of the DCF plays the role of the overlay, thus, the mode transition (MT) phenomenon of DCF can be induced by etching the outer cladding radius instead of coating overlays. The response characteristics of the effective refractive index (ERI) of the cladding mode to the outer cladding radius are analyzed. It is found that in the MT range, the change rate of ERIs of cladding modes is relatively larger than that for other ranges. Further, based on the features of the mode transition region (MTR), the phase-matching curve of the 11th cladding mode is investigated, and the response of the DCF-LPFG to the SRI is characterized by the change of wavelength intervals between the dual peaks under different outer cladding radii. The numerical simulation results show that the SRI sensitivity is greatly improved, which is available to 3484.0 nm/RIU with the fitting degree 0.998 in the SRI range of 1.33-1.37. The proposed DCF-LPFG can provide new theoretical support for designing the DCF-LPFG refractive index sensor with excellent performances of sensitivity, linearity and structure.

Changes In Protein and Its Components of High and Low Protein Varieties during Seed Development and Maturation of Soybeans (대두(大豆) 고저단백질(高低蛋白質) 품종(品種)의 성숙중(成熟中) 종실(種實)의 발육(發育)과 단백질(蛋白質) 및 그 구성분(構成分)의 변화(變化))

  • Lee, Jong Suk
    • Korean Journal of Agricultural Science
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    • v.5 no.2
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    • pp.56-67
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    • 1978
  • This study was conducted to characterize comparatively the accumulative patterns of protein and oil, temporal changes in electrophoretic components of proteins during seed development and maturation for the soybean varieties with high, medium and low protein contents. 1. The dry matter of the developing seed increases slowly for the first 22 days after flowering, followed by rapid linear increase for 20 to 30 days and further slow increase for 5 to 15 days attaining its maximum. During the period 12 to 27 days after flowering the protein content of seed increases rapidly while oil content increases rapidly. Following this period of rapid changes, there was period of slow increase until 40 to 47 days after flowering and no seizable further change in the content of both protein and oil. 2. The high protein variety, Saikai # 20, was characterized by shorter period and lower rate of decrease in protein content during the early period, followed by longer period and higher rate of increase in protein content, with earlier stop of oil accumlation during the seed development. 3. The low protein and high oil variety, Shelby, was characterized by longer period of decrease in protein content and shorter period of increase in protein content in contrast to the longer period of slow oil increase during seed development. 4. The temporal pattern of protein component accumulation during seed development was distinctly different among varieties differing in protein content. The time of distinct appearance of all the protein components identifiable in the matured seeds was in accordance with the end of d crease in the protein content of seed. A component having Rm of 0.03 which was absent in the matured seeds was identifiable during the first 17 days after flowering. 5. The high protein variety, Saikai # 20, had much higher compositioral ratio of the component a from the early days of seed development and it continued to increase until 47 days after flowering, while the increase in the composition of the component a stopped as early as 27 days after flowering in the other lower protein varieties. 6. The composition of the component b increased during the period from 17 to 42 days after flowering in all the varieties tested, but the rate of increase during the period was lowest in the high protein variety, Saikai # 20.

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Consideration and Prospect of the Historical Development of The Korean Buddhist music (한국 불교음악의 역사적 전개 고찰과 전망)

  • Song, Ji-won
    • (The) Research of the performance art and culture
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    • no.42
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    • pp.77-106
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    • 2021
  • The history of The Korean Buddhist music dates back to as early as the 2nd year of Goguryeo King Sosoorim's reign (372) when Buddhism was introduced to the land for the first time and should cover the entire development to this date, which spans over 1,600 years. The extensive scope of research is overwhelming and research efforts are limited at best. Against this backdrop, this study aims to examine how the historical development of The Korean Buddhist music has unfolded over such a long period of time and to understand how the Buddhist music is supposed to further develop in this land in and after the 21st century. Since the Three Kingdoms period, followed by Goryeo and Joseon Dynasty period, Japanese colonial period, and to this date, the history of the Buddhist music has unfolded in line with the 'ups and downs of the history of Buddhism'. The Buddhist music is characterized by various development paths based on historical peculiarities over different periods, including protection by the royal family during the Three Kingdoms period, aspect of Buddhist music during the Goryeo Dynasty period, policy to worship Confucianism and suppress Buddhism during the Joseon Dynasty period, harsh repression of Buddhism during the Japanese colonial period, and the present Buddhist music seeking new ways of proliferating Buddhism among the public, which requires an effort to understand the different characteristics of different periods by identifying key perspectives and tasks of Buddhist music in different periods. In this vein, this article includes not only the history of 'Beompae(Buddhist Chant)', a collective term for Buddhist music in a narrow sense but also all Buddhist music characterized by with Buddhism that is communicated in this land and extends its coverage even to Chanbulga(Buddhist hymn)讚佛歌 music created in and after the 20th century. It also examines the historical development of Buddhism related music in this land. Another task of this article is to understand the Myeongching-gagok 名稱歌曲 sung by monks in the early Joseon Dynasty period, music created for public mission work during the Joseon Dynasty period, the meaning of the existence of 'Hwacheong' 和請, and the traces of Buddhist music existing in the music of the Joseon Dynasty period.

Impact of antimicrobial resistance in the $21^{st}$ century

  • Song, Jae-Hoon
    • Proceedings of the Korean Society for Applied Microbiology Conference
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    • 2000.04a
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    • pp.3-6
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    • 2000
  • Antimicrobial resistance has been a well-recognized problem ever since the introduction of penicillin into clinical use. History of antimicrobial development can be categorized based on the major antibiotics that had been developed against emerging resistant $pathogens^1$. In the first period from 1940 to 1960, penicillin was a dominating antibiotic called as a "magic bullet", although S.aureus armed with penicillinase led antimicrobial era to the second period in 1960s and 1970s. The second stage was characterized by broad-spectrum penicillins and early generation cephalosporins. During this period, nosocomial infections due to gram-negative bacilli became more prevalent, while those caused by S.aureus declined. A variety of new antimicrobial agents with distinct mechanism of action including new generation cephalosporins, monobactams, carbapenems, ${\beta}$-lactamase inhibitors, and quinolones characterized the third period from 1980s to 1990s. However, extensive use of wide variety of antibiotics in the community and hospitals has fueled the crisis in emerging antimicrobial resistance. Newly appeared drug-resistant Streptococcus pneumoniae (DRSP), vancomycin-resistant enterococci (VRE), extended-spectrum ${\beta}$-lactamase-producing Klebsiella, and VRSA have posed a serious threat in many parts of the world. Given the recent epidemiology of antimicrobial resistance and its clinical impact, there is no greater challenge related to emerging infections than the emergence of antibiotic resistance. Problems of antimicrobial resistance can be amplified by the fact that resistant clones or genes can spread within or between the species as well as to geographically distant areas which leads to a global concern$^2$. Antimicrobial resistance is primarily generated and promoted by increased use of antimicrobial agents. Unfortunately, as many as 50 % of prescriptions for antibiotics are reported to be inappropriate$^3$. Injudicious use of antibiotics even for viral upper respiratory infections is a universal phenomenon in every part of the world. The use of large quantities of antibiotics in the animal health industry and farming is another major factor contributing to selection of antibiotic resistance. In addition to these background factors, the tremendous increase in the immunocompromised hosts, popular use of invasive medical interventions, and increase in travel and mixing of human populations are contributing to the resurgence and spread of antimicrobial resistance$^4$. Antimicrobial resistance has critical impact on modem medicine both in clinical and economic aspect. Patients with previously treatable infections may have fatal outcome due to therapeutic failure that is unusual event no more. The potential economic impact of antimicrobial resistance is actually uncountable. With the increase in the problems of resistant organisms in the 21st century, however, additional health care costs for this problem must be enormously increasing.

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History of Korean Nursing Education (1900-2000) (한국간호교육 100년 발달사적 연구(1900-2000))

  • Lee, So-Woo
    • The Journal of Korean Academic Society of Nursing Education
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    • v.6 no.2
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    • pp.303-326
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    • 2000
  • Only one hundred years of history in nursing education in Korea is not enough to develop the subject fully as a science. However, the development of Korean nursing education is a great historical event, because Korean nursing education has been accepted by a male-oriented Korean society and has led to a new paradigm in the new millenium. These results are largely due to the Korean people's high enthusiasm for education, as well as Korean women's diligence. I think these 100 years of history can be divided into five periods: (1) the Sunlight period (1900-1911) (2) the New born period (1912-1945) (3) the Settle-down period (1946-1960) (4) the Marked Growth period (1961-1980) (5) the Jumping Period (1981-2000) These classifications are characterized by changes in the educational system, a changed nursing curriculum, educational goals, educational outcomes, and implications. The characteristics of historical development of Korean nursing education was evaluated in three dimensions: structures, contents, and outcome. The structure of Korean nursing education consists of a 3-year program and a 4-year program. Most nursing leaders in Korea hope that these two programs will converge into one system. Secondly, the contents of nursing education in Korea underwent very active changes, according to historical development. These changes in the nursing curriculum have been developed to provide a professional education and develop nursing education as a modern science. Lastly, as to the results of nursing education in Korea, the education was needed to turn out advanced specialists in nursing. In the new millenium, knowledge and information will be the driving forces behind social development. A nation's level of development and creativity in nursing education is the most potent determinant of the future of Korean nursing. The best way to prepare for future challenges will be to create the backbone of a nursing education system. Hence, well-educated nurses in graduate programs should be turned into advanced specialists in nursing. These groups will upgrade the image of Korean nurses, and will have strong influence to improve patient care and the health situation in Korea.

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The Grid System of Women's Jeogori in Joseon Dynasty (조선시대 여성저고리의 그리드체계)

  • Han, Eun-Hye
    • Journal of the Korean Society of Costume
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    • v.62 no.6
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    • pp.200-217
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    • 2012
  • The purpose of this research is to examine the specificity of grids to define the characteristics of clothes styles in the Joseon Dynasty period. The significance of examining of the specificity of grids is to find out arbitrary types of the features of grids involved in structuring the Jeogori in the Joseon Dynasty period one by one. The Visual Linguistic Theory was introduced as a methodological tool to exquisitely analyze the characteristics of grids in deep structures of Jeogori in the Joseon Dynasty period. This theory strives to examine sample distribution, the distribution of samples by quality and the distribution of the types of ploidy features. Through the examination, the results are as follows. The grid systems of the Jeogori consisted of diverse proportion systems reaching 86 cases, that is, sequence systems composed of multi-functional, multi-combined bodies. Most ornamental grids had feature angles distributed in a range of $2-20^{\circ}$ that showed a common preference for low sloped diagonal lines or small curvature. Although the preference for certain feature angles were prominent, the feature angles that were used were generally distributed evenly among diverse feature angles to show the characteristics of separation. Therefore, Jeogori makers in the Joseon Dynasty period can be considered as having experimented with many proportion systems to show their aesthetics. In conclusion, based on the results of the examination of feature distributions and related methods to allocate ploidy features, O-type accounted for 66% and thus it was identified that the Jeogori was characterized by O-type. Therefore, it was identified that the characteristic of the Jeogori in the Joseon Dynasty period consisted of O-type fractal structures which are formative structures unique to our nation.

Change of Synoptic Climatology Associated with the Variation of Summer Rainfall Amount over the Korean Peninsula Around 1993/1994 (1993/1994년을 기점으로 나타난 한반도 여름철 강수량 변동의 종관기후학적 원인)

  • Kim, Jae-Hoon;Lee, Tae-Young
    • Atmosphere
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    • v.22 no.4
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    • pp.401-413
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    • 2012
  • In this study, an investigation has been carried out to understand 1) temporal variation of rainfall amount in summer over south Korea during the 30-year period of 1979-2008 and 2) the relationship between the variation of rainfall amount and the change of large-scale monsoon circulation around 1993/1994 over East Asia. The analysis of rainfall amount is carried out separately for whole summer (June-August), climatological Changma period of 23 June-23 July, and August to consider variations within summer. To relate the variation of rainfall amount with the change of large-scale circulation, we have considered two 15-year periods of 1979-1993 and 1994-2008. This study has used observations at 58 stations in South Korea and NCEP-NCAR $2.5^{\circ}{\times}2.5^{\circ}$ reanalysis data. The major change in synoptic environment for the Changma period is characterized by the intensified anticyclone over Mongolia during 1994-2008, which results in a weak meridional oscillation of Changma front. As a result, rainfall amount for the Changma period and the frequency of extreme events have significantly increased after 1993/1994. A major change of synoptic environment for August is the significant westward extension of the western Pacific subtropical high, which allows not only more moisture transports but also stronger cyclonic circulation over the Korean peninsula. Rainfall amount for August and frequency of extreme events have also increased after 1993/1994. However, variability of rainfall amount is larger for August than that for the Changma period, with some years showing very dry August (monthly rainfall amount less than 150 mm).

Analysis and Illustration of the Formative Characteristics of Po Discovered During the period of the Japanese Invasion of Korea (1592-1598) (임진왜란기(1592~1598) 출토 포의 형태분석과 일러스트화)

  • Lee, Joo-Young;Lee, Kyung-Hee
    • Journal of the Korean Society of Costume
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    • v.60 no.9
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    • pp.58-76
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    • 2010
  • In this study, the shapes of po worn by military officers who served During the period of Japanese Invasion of Korea(1592-1598) were investigated. Findings of the study can be summarized as follows. Various types of po that military officers usually wore during the period of Japanese Invasion of Korea includes jikryeong, dapho, dopo, cheolik, aekjureum, jangeui, jungchimak and bangryeongpo. Out of these types, cheolik and jungchimak were most often used by the officers. Po that were usually worn by military officers during the period of Japanese Invasion of Korea as above mentioned is characterized as no difference in length between the front and back of the costume, kalgit and a pair of coat strings which are directly attached to po. The sleeves of the costume are bean chaff-shaped in some cases and just narrowly shaped in other cases. Similarly, the outer seop of po was either double-layered or single-layered. For jikryeong and dapho, mu is usually type of outside wrinkle. For dopo, its rear kit has the inner hem whose right and left edges are usually distant, respectively by 6~16cm, from the back center of the costume. Cheolik and aekjureum usually have either fine or broad pleats. For jangeui and jungchimak, mu is usually trapezoid in shape. Among various types of po which were usually worn by military officers during the period of Japanese Invasion of Korea, most representative are jikryeong from the tombs of Bae Cheon jo, dapho from Shin Yeo Gwan, dopo from general Bak and Bae Cheon Jo, cheolik from Nam Yoo and Cho Gyeong, aekjureum from Shin Yeo Gwan, jangeui from Kim Ham, jungchimak from Bae Cheon jo and bangryeongpo from Cho Gyeong.