• 제목/요약/키워드: short period component

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Disaster Events Detection using Twitter Data

  • Yun, Hong-Won
    • Journal of information and communication convergence engineering
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    • 제9권1호
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    • pp.69-73
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    • 2011
  • Twitter is a microblogging service that allows its user to share short messages called tweets with each other. All the tweets are visible on a public timeline. These tweets have the valuable geospatial component and particularly time critical events. In this paper, our interest is in the rapid detection of disaster events such as tsunami, tornadoes, forest fires, and earthquakes. We describe the detection system of disaster events and show the way to detect a target event from Twitter data. This research examines the three disasters during the same time period and compares Twitter activity and Internet news on Google. A significant result from this research is that emergency detection could begin using microblogging service.

침체굵기에 따른 자침의 근피로도 회복에 미치는 영향 (Effects of Acupuncture on the Muscle Fatigue Recovery in Different Diameters of Needle)

  • 황요순;박진수;구성태
    • Korean Journal of Acupuncture
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    • 제29권4호
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    • pp.634-642
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    • 2012
  • Objectives : The aim of the study is to find out whether effect of acupuncture is depending on the diameter of needle, which is a possible component of dose of acupuncture needling. Methods : To compare acupuncture effects in different diameters of needle, we measured the changes in muscle fatigue recovery using surface electromyogram(sEMG) in healthy 8 volunteers. Muscle fatigue was induced by 20 times sit-up for 1 min. Immediately after induction of muscle fatigue, acupuncture needle was inserted into ST36 or ST25 for 10 min by diameters of 0.20 mm, 0.30 mm, or 0.40 mm needles. The sEMG recording was followed by acupuncture for 30 min. As a control group, sEMG was recorded for the same period at rest after muscle fatigue induction. Results : In both of ST 36 and ST 25, stimulation with 0.4 mm diameter needle showed significant rapid recovery followed by short period of muscle fatigue increase. Stimulation with 0.2 mm diameter significantly suppressed the increase of muscle fatigue. Conclusions : These data suggest that acupuncture effect is, at least in part, dependent on diameter of needle. Therefore, diameter of needle is also considered to achieve effective outcome of acupuncture.

The Effect of wool in patients with chronic obstructive pulmonary disease

  • Emine, Kiyak
    • 셀메드
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    • 제7권3호
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    • pp.12.1-12.6
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    • 2017
  • The purpose of this study was to analyze the effect wool in patients with chronic obstructive pulmonary disease. The study was conducted experimentally on 53 patients with chronic obstructive pulmonary disease attending the chest diseases polyclinic of a hospital located in Erzurum. A randomized selection method was used to categorize patients into two groups; a treatment (n = 27), and a control group (n = 26). Patients in the treatment group (pre-test measurements were taken) wore wool vests for a period of three months, while patients in the control group wore cotton vests (placebo) for the same duration; post-test measurements were taken for both groups at the end of the three-month period. The Medical Outcomes Study Short Form 36, the St. George's Respiratory Questionnaire, and pulmonary function tests were used to collect data. Results concluded that there was a significant decrease (p < 0.05) in the overall score of the St. George's Respiratory Questionnaire, and the symptom, effect, and activity mean scores, while there was a significant increase (p < 0.05) in the SF-36 physical functioning, general health, bodily pain, role physical, vitality, role emotional, social functioning, mental health, physical and mental component summary mean scores of patients in the treatment group. Results of the study concluded that the symptoms, activity, disease effectiveness, and quality of life improved in patients that wore wool vests.

동남극 윌크스랜드 대륙대의 마이오세 중-후기 동안 생물기원 오팔 생산과 고기후 변화(IODP Exp 318 Site U1359) (Biogenic Opal Production and Paleoclimate Change in the Wilkes Land Continental Rise (East Antarctica) during the Mid-to-late Miocene (IODP Exp 318 Site U1359))

  • 송부한;김부근
    • Ocean and Polar Research
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    • 제37권1호
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    • pp.23-35
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    • 2015
  • A 450 m-long sediment section was recovered from Hole U1359D located at the eastern levee of the Jussieau submarine channel on the Wilkes Land continental rise (East Antarctica) during IODP Expedition 318. The age model for Hole U1359D was established by paleomagnetic stratigraphy and biostratigraphy, and the ages of core-top and core-bottom were estimated to be about 5 Ma and 13 Ma, respectively. Biogenic opal content during this period varied between 3% and 60%. In the Southern Ocean, high biogenic opal content generally represents warm climate characterized by the increased light availability due to the decrease of sea-ice distribution. The surface water productivity change in terms of biogenic opal content at about 10.2 Ma in the Wilkes Land continental rise was related to the development of Northern Component Water. After about 10.2 Ma, more production of Northern Component Water in the North Atlantic caused to increase heat transport to the Southern Ocean, resulting in the enhanced diatom production. Miocene isotope events (Mi4~Mi7), which are intermittent cooling intervals during the Miocene, appeared to be correlated to the low biogenic opal contents, but further refinement was required for precise correlation. Biogenic opal content decreased abruptly during 6 Ma to 5.5 Ma, which most likely corresponds to the Messinian salinity crisis. Short-term variation of biogenic opal content was related to the extent of sea-ice distribution associated with the location of Antarctic Polar Front that was controlled by glacial-interglacial paleoclimate change, although more precise dating and correlation will be necessary. Diatom production in the Wilkes Land continental rise increased during the interglacial periods because of the reduced sea-ice distribution and the southward movement of Antarctic Polar Front.

Component Analysis of Thermally Activated Building System in Residential Buildings

  • Chung, Woong June;Lee, Yu Ji;Yoo, Mi Hye;Park, Sang Hoon;Yeo, Myoung Souk;Kim, Kwang Woo
    • Architectural research
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    • 제16권4호
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    • pp.203-210
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    • 2014
  • The packaged terminal air conditioner, the typical cooling system for the residential buildings, consumes a large amount of electricity in a short period time during peak hours. In order to reduce the peak load and conserve the electricity, the thermally activated building system can be used as a secondary system to handle the partial cooling load. However, the thermally activated building system may cause condensation and under-cooling. Thus, design of both systems should be performed with careful investigation in characteristics of both systems to amplify the advantages. Since the thermally activated building system has the time-delay effect which may cause under-cooling, the system is designed to handle the base load of the building. Hence, simple simulation with EnergyPlus was performed to observe the characteristics of cooling load in residential buildings. Once the possible range of the load handling ratio of the thermally activated building system was decided, characteristics of system was analyzed in terms of hardware component and operation parameters. The hardware components were analyzed in plant and system aspects and the operation parameter was evaluated in the thermal comfort aspect. As the load handling ratio increased, the thermal comfort increased due to the lower radiant mean temperatures. Within the range of thermal comfort, the several adjustments were made in setpoint temperature and electricity consumptions of difference cases were observed to decide which components and parameters were important for designing the systems.

주성분분석에 의한 거금수도의 수질환경 및 식물플랑크톤 변동 요인 해석 (The analysis of variational characteristics on water quality and phytoplankton by principal component analysis(PCA) in Kogum-sudo, Southwestern part of Korea)

  • 윤양호;박종식
    • 한국환경과학회지
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    • 제9권1호
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    • pp.1-11
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    • 2000
  • A study on the variational characteristics of water quality and phytoplankton biomass by principal component analysis(PCA) was carried out in Kogum-sudo from February to October in 1993. We analyzed PCA on biological factors such as chlorophyll a and phytoplankton cell numbers for centric and pennate diatoms, phytoflagellates, and total phytoplankton as well as physico-chemical factors as water temperature, salinity, transparency, dissolved oxygen(DO), saturation of DO, apparent oxygen utilization (AOU), chemical oxygen demand(COD), nutrient (ammonia, nitrite, nitrate, phosphate and silicate), N/P ratio and suspended solid(SS). The source of nutrients supply depended on the mineralization of organic matters and inputs of seawater from outside rather than runoff of freshwater. The phytoplankton biomass was changed within short interval period by nutrients change. And it was controlled by the combination of several environmental factors, especially of light intensity, ammonia and phosphate. The marine environmental characteristics were determined by the mineralization of organic matters in winter, by runoff of freshwater including high nutrients concentration in spring, by ammonia uptake and high phytoplankton productivity in summer, and phosphate supplied input seawater from outside of Kogeum-sudo in autumn. And Kogum-sudo was separated with 2 regions by score distributions of PCA. That is to say, one region was middle parts of straits which was characterized by the mixing seawater and the accumulated organic matters, other one region was Pungnam Bay and the water around Kogum Island which was done by high phytoplankyon biomass and productivity year-round.

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광 주파수 빗으로부터 단일 광 주파수 성분의 선택적 추출 (Selective Extraction of a Single Optical Frequency Component from an Optical Frequency Comb)

  • 문한섭
    • 한국광학회지
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    • 제34권6호
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    • pp.225-234
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    • 2023
  • 모드 잠금 레이저는 주기성을 가지고 짧은 시간 동안 레이저 출력이 펄스로 동작한다. 그러나 시간-주파수 영역에서 모드 잠금된 펄스 레이저의 펄스 반복률의 주기성은 푸리에 변환으로 일정한 주파수 간격을 가진 광 주파수 빗과 같이 이해된다. 이때 광 주파수 빗의 각 주파수 성분은 연속적으로 발진하는 수십만 개의 단일 주파수 성분을 가진 continuous-wave 레이저들과 같다. 광 주파수 빗은 약 20년 전에 개발되어 세계에서 가장 정밀한 원자 시계의 개발을 가능케 하고 안정된 광 주파수를 정밀하게 전송하는 데에 사용되었으며, 다양한 응용연구로도 발전했다. 본 논문에서는 광 주파수 빗의 단일 주파수 구성 요소를 선택적으로 추출하고, 광 빗의 주파수 구성 요소를 제어하는 연구를 소개한다. 또한 광 주파수 빗의 개념과 원리를 해설함으로써 시간-주파수 도메인에서 빛의 특성을 이해하고, 광 주파수 빗을 활용한 다양한 응용 연구를 개발하는 데 도움을 주고자 한다.

조현병/조현정동장애 환자에서 1년간의 Clozapine 투여가 혈소판 활성도에 미치는 영향에 관한 후향적 연구 (A Retrospective Study on the Effect of 1-Year Clozapine Administration on Platelet Activity in Patients with Schizophrenia or Schizoaffective Disorder)

  • 장은자;이종욱;김승준;오홍석;이나현;임우영;김지웅
    • 정신신체의학
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    • 제28권1호
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    • pp.36-41
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    • 2020
  • 연구목적 클로자핀은 뇌심혈관 질환의 발생가능성을 높이는 것으로 알려져 있으며, 혈소판의 활성화 정도는 뇌심혈관 질환의 발생과 관련이 있을 것으로 생각되어왔다. 저자들은 이전 연구에서 단기간의 클로자핀 투여 후 혈소판 활성도가 증가함을 관찰하였다. 본 연구는 이에 대한 후속 연구로 클로자핀을 1년의 기간 동안 장기간 지속 투여하였을 때, 혈소판 활성도에 어떤 영향을 미치는지를 알아보기 위해 시행하였다. 방 법 조현병 혹은 조현정동장애의 치료를 위해 최소 1년의 기간 동안 지속적으로 클로자핀을 투여 받은 환자들의 의무기록을 후향적으로 검토하였다. 혈소판의 활성도는 평균혈소판요소 값을 이용하여 측정하였다. 결 과 총 24명의 환자를 대상으로 하였고, 연구 대상자 중 남성은 9명(37.5%), 여성은 15명(62.5%) 였다. 윌콕슨부호-순위검정에서 초기 및 1년 경과 시점에서의 평균혈소판요소 값 사이의 유의한 변화는 관찰되지 않았다. 결 론 1년간의 지속적인 클로자핀 투여에도 평균혈소판요소의 유의한 변화가 관찰되지 않았다. 단기간의 클로자핀 투여 시 평균혈소판요소 값에 현저한 저하를 관찰하였던 저자들의 이전의 연구 결과를 함께 고려해 볼 때, 본 연구의 결과는 클로자핀 투여 기간에 따라 혈소판의 활성도가 변화할 가능성을 시사한다.

고주파절제술을 통한 선택적 신경차단법을 이용한 미간주름의 개선 (Treatment of glabellar frown lines using selective nerve block with radiofrequency ablation)

  • 황용석;김영석;노태석;탁관철;이건창
    • Archives of Plastic Surgery
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    • 제36권2호
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    • pp.205-210
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    • 2009
  • Purpose: Corrugator supercilii muscle pulls eyebrow to inferomedial direction and produces the vertical component of the glabellar line formation. Current techniques for eliminating of glabellar frown include direct resection of corrugators and botulinum toxin injection. Muscle resection in endoscopic face lift procedure is relatively complex and has many disadvantages ranging from possible nerve injury, postoperative edema, pain and a long recovery period. The Botox treatment on the other hand is much more simple in technique but has a short duration of action. The authors have attempted new ways of finding improved treatment of the glabellar frown by selectively blocking of motor nerves innervating the corrugator supercili muscle by using radiofrequency ablation technique. Methods: A total of 80 patients were recruited in our study during the period between Feb. 2007 to June 2008. A probe was introduced from the supraorbital ridge and advanced to the corrugator supercilii muscle. Nerve stimulator was then used to locate the nerve innervating the corrugator and radiofrequency ablation of the nerve was done. Results: In all patients, there were marked improvement in glabellar frown after treatment. There were no reported cases of any relapses during the follow up period. No complication was noted such as facial nerve injury. No patient complained of any adverse symptoms other than slight discomfort due to swelling of the operation site. Conclusion: The treatment of glabellar frown lines using selective nerve block with radiofrequency ablation was not only less invasive but also excellent in surgical outcomes.

발전소 저탄장에 적용되는 풀코드스위치 부품의 구조최적화 3D 프린팅 제작기술 개발 (Structure Optimization and 3D Printing Manufacture Technology of Pull Cord Switch Components Applied to Power Plant Coal Yard)

  • 이혜진
    • 한국산학기술학회논문지
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    • 제17권10호
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    • pp.319-330
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    • 2016
  • 3D 프린팅 기술은 다양한 산업분야에서 개념모델 및 기능성 시제품을 제작하는데 많이 응용되고 있지만, 3D 프린팅 소재 및 제작된 제품 신뢰성 등의 여러 가지 이유로 상용화 제품으로 적용되는 데 한계가 존재한다. 본 논문에서는 3D 프린팅 기술을 이용한 산업적 응용분야 중 하나로 발전소 저탄장에 사용되는 풀 코드 스위치 모듈의 부품들 중 잦은 돌발 상황으로 인해 파손이 자주 발생하는 허브 구동부와 레버 고정부 부품들에 대해 현장에서 작업자들이 단기 대체부품으로 적용이 가능하도록 하는 부품 최적 설계 및 FDM 방식 3D 프린팅 제조공정기술에 대한 연구결과를 제시하였다. 3D 프린팅 기술의 경우 소재 적용에 있어서 한계가 존재하므로, 본 논문에서는 구조 최적화 설계를 통해 구조 안정성을 확보하는 방안에 대해 연구를 수행하였다. 허브 구동부 부품에 대해 내부 구조 형상 및 구조 설계 변수 최적화를 수행하여 좌측구동모드에서는 안전계수가 153.67% 증가한 1.243을 확보할 수 있었으며, 우측구동모드에서는 404.96% 증가한 3.156을 확보할 수 있었다. 레버 고정부 부품의 경우, 반복적인 스위칭 구동에 의한 굽힘 모멘트로 인해 발생하는 파손을 최소화하기 위해 구조 최적화 설계를 수행하여 26% 증가한 구조 안전계수(7.52)를 확보할 수 있었다. 본 연구를 통해 3D 프린팅 기술을 단기 대체부품 제조공정에 적용함에 있어서 소재 최적화를 통한 설계보다는 3D 프린팅 공정의 적층특성을 활용한 구조적 최적화 설계기법 이 더욱 유연한 결과를 도출할 수 있음을 확인할 수 있었다.