• 제목/요약/키워드: Predominant Period

검색결과 288건 처리시간 0.027초

우리나라 남해안지역 신석기시대 패총 출토 패류 (Molluscan Remains from the Neolithic Shell Middens in the Southern Coast, Korea)

  • 안덕임
    • 한국패류학회지
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    • 제10권2호
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    • pp.1-9
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    • 1994
  • Molluscs from the Neolithic shell middens (Sugari, Pudjeong, Tongsamdong, Sangnodaedo, Sandeung, Yondaedo, Songdo and Kupyongri) in the southern coast, Korea, consisted of marine, fresh-water and land molluscs. Among these, intertidal species were exploited most abundantly as food resources, indicating a high dependence of intertidal shellfish collection activities. Especially oysters were the most abundant in these sites except Tongsamdong where mussels were predominant, indicating oysters were the most important food resources. Land snails from the sites consisted of woodland and open land species. Woodland species were more abundant than openland species, suggesting that there was a woodland environmint around the sites. Marine and land mollusc species from the sites are common in these rigions today, indicating no large-scale emvironmental changes have occurred since these middens formation period.

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지진시 방콕지역의 지반운동에 대한 동력학적 연구 (Dynamic Analysis of Ground Motion During Earthquake in the Bangkok Area)

  • 김상환
    • 한국지반공학회지:지반
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    • 제1권1호
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    • pp.13-20
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    • 1985
  • SHAKE 프로그램을 이용하여 연약지반으로 분포되어 있는 방콕지역에 대한 지진표답을 지표면의 가속도응답 스펙트럼과 최대 가속도로서 분석하였다. 기초암반의 최대 가속도와 부월주기가 증가됨에 따라 지표면의 최대 가속도는 증가되고 그 값은 0.3g 로 수관되었다. 아울러 지진응답 스펙트럼의 성질에 대해서도 설명되었다.

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입력지진파 차이로 인한 지반응답 분산도 평가 연구 (Evaluation of Ground Response Dispersion Caused by the Difference of Input Ground Motions)

  • 김진만;류정호;권기철;심재호;김제경
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2007년 가을학술발표회
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    • pp.293-304
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    • 2007
  • In 2007, Round Robin Test (RRT) on ground response analyses has been conducted by the technical committee of Soil Dynamics and Geotechnical Earthquake Engineering of Korean Geotechnical Society. Total 14 teams have reported 16 different results. This paper discusses the evaluation of ground response dispersion caused by the difference of input ground motions. In order to determine the characteristics of ground response, this study analysed the peak ground acceleration, predominant period, and response spectrum of reported ground surface motions. The results suggest that ground response dispersion due to the difference of input ground motions can be significant.

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임펠러 형상에 따른 교반기의 유동특성에 관한 연구 (A Study on the Flow Characteristics of Mixer by Impeller Types)

  • 양창조;최민선;이영호
    • Journal of Advanced Marine Engineering and Technology
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    • 제27권7호
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    • pp.899-905
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    • 2003
  • Mixers are used in several industrial applications where it is necessary to strongly mix reactants in a short period of time (eg. reaction injection molding, ceramics manufacturing, crystallization). However, despite their widespread use, mixing flow characteristics in these systems have not been rigorously investigated. Influence of blade shapes on the mixing time and the power consumption per unit volume in two kinds of impeller including the mixing effects are studied by PIV experiment. A series of the experiments were carried out to achieve a better mixing effect in simple baffle arrangement and tall vessel with modified impellers(two kinds of blades : pitched blade turbine and rushton turbine). Results show that periodic vortex from the mixing layer is predominant and related unsteady flow characteristics prevail over the entire region.

Evaluation of seismic energy demand and its application on design of buckling-restrained braced frames

  • Choi, Hyunhoon;Kim, Jinkoo
    • Structural Engineering and Mechanics
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    • 제31권1호
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    • pp.93-112
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    • 2009
  • In this study seismic analyses of steel structures were carried out to examine the effect of ground motion characteristics and structural properties on energy demands using 100 earthquake ground motions recorded in different soil conditions, and the results were compared with those of previous works. Analysis results show that ductility ratios and the site conditions have significant influence on input energy. The ratio of hysteretic to input energy is considerably influenced by the ductility ratio and the strong motion duration. It is also observed that as the predominant periods of the input energy spectra are significantly larger than those of acceleration response spectra used in the strength design, the strength demand on a structure designed based on energy should be checked especially in short period structures. For that reason framed structures with buckling-restrained-braces (BRBs) were designed in such a way that all the input energy was dissipated by the hysteretic energy of the BRBs, and the results were compared with those designed by conventional strength-based design procedure.

폐 Aspergillosis 14 예 보고 (The clinical study of pulmonary aspergillosis -A report of 14 cases-)

  • 박철호
    • Journal of Chest Surgery
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    • 제19권4호
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    • pp.715-721
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    • 1986
  • 14 cases of pulmonary aspergillosis were managed surgically over a 6 year period in the Dept. of Thoracic Surgery Inje Medical College, Paik Hospital were reviewed. 1. Male, female ratio was 9:5 male predominant and 2,3,4 decade were prevalent. 2. The most prevalent chief complaint was hemoptysis, 9 cases [63%] and other symptoms were chronic productive cough 4 cases. 3. Preoperative diagnostic accuracy ratio was 0.21 [3 cases only]. 4. Right upper lobe was most common involving site, 7 cases [5[%], 13 lobectomy and 2 segmentectomy were performed. 5. Pathological underlying diseases were pulmonary tuberculosis 8 cases [57%], bronchiectasis and lung abscess was 1 case, no underlying disease were 4 cases. 6. One major postoperative complication was symptomatic residual dead space which was managed by thoracoplasty.

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흉부 손상의 임상적 고찰 (Clinical Analysis of Chest Trauma; Analysis of 247 patients)

  • 김승규
    • Journal of Chest Surgery
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    • 제26권12호
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    • pp.944-949
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    • 1993
  • Clinical analysis were performed on 247 cases of thoracic trauma, those were admitted & treated at the department of thoracic & cardiovascular surgery,Hanyang University Hospital during the period from Jan,1989 to June,1992. Age distribution of those was from 2 to 80 years old & mean age was 38 years old. The ratio of male to female patient was 186:61 [3:1].This ratio revealed high incidence in male patient. The most common cause of trauma was traffic accident in this series.The modes of injury were as follows: traffic accident 124 cases[50.2%],fall down 52 cases[21.05%], stab wound 47 cases[19.03%] and gun-shut wound 1 case.Ellapse time from accident to admission were 141 cases [57.09%] under 6 hr.Rib fracture were observed in 159 cases[64.37%], hemo or pneumothorax were observed 134 cases[54.25%] of total cases and location distributed Right:Left:Both[74:112:37], in left predominant. Conservative,non-operative treatment were performed in 128 cases and operation[open thoracotomy] 32 cases.Mortality was 1.6%[4 cases] & most common cause of death were due to irreversible shock with brain edema. Conclusively, more evaluation & co-operation of other department were expected treatment & better prognosis.

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돼지고기 드립의 몇가지 특성과 염지 효과 (Some Properties and Curing Effect of Drip from Frozen-thawed Pork meat)

  • 김미숙
    • 한국식품영양학회지
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    • 제12권4호
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    • pp.370-374
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    • 1999
  • This study was carried out to some properties and curring effect of drip obtained from frozen-thawed park loin ham belly and imported belly by thawing process at 4$^{\circ}C$. Moisture content and pH value of drips were 88.05~90.85% and 5,72~6.05 and do not show significant differences between each samples. Protein contents were 11.07, 8.85, 8,76 and8,13% in the drips from domestic pork loin, ham, belly and imported belly, respectively. Approximately 99% of the drip were constituted with moisture and protein in any part of domestic pork and imported belly. Glutamic acid proline glycine, alanine and lysine were the predominant amino acid in the drips. Curing process of the drip by nitrite increased the pH value and total amino acid content. The residual nitrite decreased during the period of curing and total plate counts in drip with nitrite did not reach 1$\times$105CFU/g until 7 days.

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Prevalence of Hepatitis B Virus Infection in Kaifeng, China: A 5-year Observation

  • Zhang, Jinli;Ma, Chunyan;Li, Hang;Steele, Michael;Idris, Adi
    • 한국미생물·생명공학회지
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    • 제46권4호
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    • pp.430-433
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    • 2018
  • Hepatitis B is a major health problem in China. However, little is known about the prevalence of hepatitis B virus (HBV) in Kaifeng, the major urban capital of Henan province, China. We found that HBV prevalence increased with age and that chronic HBV was predominant in adult males in Kaifeng. The HBV prevalence remained unchanged over a 5-year period for all age groups. Alarmingly, 25% of the population remained unvaccinated and potentially susceptible to future HBV infection. HBV immunization and health education initiatives should be carried out in this population to further reduce the overall prevalence of HBV.

Clinical Manifestations, Epidemiologic Characteristics, and Disease Burden of the Coronavirus Disease-19 in Children Ages 5-11 Years Old

  • Kang, Hyun Mi;Park, Ji Young;Choe, Young June
    • Pediatric Infection and Vaccine
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    • 제29권2호
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    • pp.61-69
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    • 2022
  • Coronavirus disease 2019 (COVID-19) has been a global pandemic for over 2 years. During the Omicron (B.1.1.529) variant-predominant period in South Korea, confirmed cases among children and adolescents surged. This review found that, although younger children may be less susceptible to COVID-19 than adolescents, more research is needed on the role of children and adolescents in the disease's spread. Detailed epidemiological information about the transmissibility of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strain in children and adolescents is currently scarce, and more research is needed on the role of children and adolescents in disease's spread. There may be a difference in the proportion of cases with severe disease requiring hospitalization depending on the dominant mutant strain; however, COVID-19 generally presents with a mild-to-moderate course in children aged 5-11 years old.