• 제목/요약/키워드: lateral flow

검색결과 589건 처리시간 0.04초

양해법과 음해법을 이용한 영산강에서의 부정류해석 (Unsteady Flow Analysis in the Youngsan River Using Explicit and Implicit Finite Difference Methods)

  • 최성욱;여운광;주철;김창완;오유창
    • 물과 미래
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    • 제24권4호
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    • pp.49-58
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    • 1991
  • 영산강 유역의 89년 7월 호우에 대하여 두가지 유한차분법을 이요한 부정류해석을 실시하였다. 유한 차분법으로는 양해법의 경우 Leap Frog 기법을, 음해법은 Preissmann 기법을 사용하였고 지배방정식은 쌍곡선형 편미분방정식의 일종인 Saint Venant 식을 이용하였다. 외부경계조건으로는 상류단의 유량과 하류단의 조위를 이요하였으며 하구언을 내부경계조건으로 포함시켰다. 지천에서의 유입량과 상류단에서의 유량은 저류함수법에 의한 결과로써 시간별 입력자료로 사용되었다. 비교적 상류에 해당되는 나주지점에서 실측자료, 저류함수법 그리고 두 수치모형에 의한 계산값을 비교해본 결과 해의 정확도는 만족스러웠고 실측자료가 없는 중하류지점에서도 두 모형에 의한 계산값을 비교함으로써 상대적으로 신뢰할 수 있음을 알았다. 본 연구를 통하여 기존의 수문학적 홍수추적방법과 더불어 수치해석에 의한 부정류모형이 홍수예경보업무에 충분히 이용될 수 있음을 알 수 있었으며, 앞으로 본모형을 이용한 홍수시 배수갑문의 최적운영방안등의 연구도 기대된다 하겠다.

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플래퍼론이 전개된 플라잉윙 형상의 공력 특성에 대한 전산유동해석 (Computational Fluid Dynamics of the aerodynamic characteristics for Flying Wing configuration with Flaperon)

  • 고아림;장경식;박창환;신동진
    • 항공우주시스템공학회지
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    • 제13권5호
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    • pp.32-38
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    • 2019
  • 높은 후퇴각을 갖는 둥근 앞전 날개 형상은 앞전 와류에 의해 복잡한 유동 현상이 나타난다. 불안정한 방향 안정성을 갖는 무미익 플라잉윙의 제어를 위해서 플래퍼론이 사용된다. 본 연구에서는 플래퍼론이 전개된 비세장형, 둥근 앞전의 플라잉윙 형상의 전산해석을 수행하였으며 옆미끄럼각 및 플래퍼론에 대한 영향을 분석하였다. 공력계수 분석을 통해 양력과 항력계수에 대한 옆미끄럼각의 영향은 적으며 측력 및 모멘트 계수는 옆미끄럼각의 영향을 크게 받음을 알 수 있었다. 정적 안정성 분석을 통해 플래퍼론이 전개된 플라잉윙의 가로안정성과 방향안정성이 좋아졌음을 확인하였다. 또한 압력계수분포, 표면 마찰선의 관찰을 통해 앞전 와류 구조 및 거동을 분석하였다.

폐암 질환 진단에 활용 가능한 바이오마커 검출용 바이오칩 센서 연구 동향 (Research Trend of Biochip Sensors for Biomarkers Specific to Diagnostics of Lung Cancer Diseases)

  • 이상혁;고은서;이혜진
    • 공업화학
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    • 제29권6호
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    • pp.645-651
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    • 2018
  • 한국인의 암 사망률 1위를 차지하는 폐암은 발견되기 전까지 별다른 증상이 없어 환자는 병을 쉽게 인지하지 못하고, 기존의 진단법 또한 초기단계에는 적용이 어렵다. 해결책으로서, 분자수준에서의 체액분석을 폐암진단에 도입하는 방안이 제시되고 있다. 이를 위한 분석기기 가운데 대표적으로는 칩 기반 바이오센서가 있으며, 이 센서의 큰 장점으로는 고가의 분석장비나 숙련된 분석인력이 없이도 현장에서의 진단이 가능하다는 점이다. 본 미니총설에서는 폐암 진단에 활용가능한 혈액 내 바이오마커와 바이오칩 센서의 연구현황을 소개하고 이들의 발전가능성에 대해 논의하고자 한다.

Division of a single free flap in multiple digit reconstruction

  • Kim, Jin Soo;Song, Cheon Ho;Roh, Si Young;Koh, Sung Hoon;Lee, Dong Chul;Lee, Kyung Jin
    • Archives of Plastic Surgery
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    • 제49권1호
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    • pp.61-69
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    • 2022
  • Background Single free flaps are a commonly used reconstructive method for multiple soft tissue defects in digits. We analyzed the flap size, division timing, and degree of necrosis in cases with various types of flap division. Methods We conducted a retrospective review of the medical charts of patients who had undergone single free flap reconstruction for multiple soft tissue defects across their digits from 2011 to 2020. The flap types included were the lateral arm free flap, venous forearm free flap, thenar free flap, hypothenar free flap, anterolateral thigh free flap, medial plantar free flap, and second toe pulp free flap. Flap size, anastomosed vessels, division timing, and occurrence of flap necrosis were retrospectively investigated and then analyzed using the t-test. Results In total, 75 patients were included in the analysis. The success rate of the free flaps was 97.3%. All flaps were successfully divided after at least 17 days, with a mean of 47.17 days (range, 17-243 days) for large flaps and 42.81 days (range, 20-130 days) for the medium and small flaps (P=0.596). The mean area of flap necrosis was 2.38% in the large flaps and 2.58% in the medium and small flaps (P=0.935). Severe necrosis of the divided flap developed in two patients who had undergone flap division at week 6 and week 34. Conclusions In cases where blood flow to the flap has been stable for more than 3 weeks, flap division can be safely attempted regardless of the flap size.

Development of Enzymatic Recombinase Amplification Assays for the Rapid Visual Detection of HPV16/18

  • Ning Ding;Wanwan Qi;Zihan Wu;Yaqin Zhang;Ruowei Xu;Qiannan Lin;Jin Zhu;Huilin Zhang
    • Journal of Microbiology and Biotechnology
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    • 제33권8호
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    • pp.1091-1100
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    • 2023
  • Human papillomavirus (HPV) types 16 and 18 are the major causes of cervical lesions and are associated with 71% of cervical cancer cases globally. However, public health infrastructures to support cervical cancer screening may be unavailable to women in low-resource areas. Therefore, sensitive, convenient, and cost-efficient diagnostic methods are required for the detection of HPV16/18. Here, we designed two novel methods, real-time ERA and ERA-LFD, based on enzymatic recombinase amplification (ERA) for quick point-of-care identification of the HPV E6/E7 genes. The entire detection process could be completed within 25 min at a constant low temperature (35-43℃), and the results of the combined methods could be present as the amplification curves or the bands presented on dipsticks and directly interpreted with the naked eye. The ERA assays evaluated using standard plasmids carrying the E6/E7 genes and clinical samples exhibited excellent specificity, as no cross-reaction with other common HPV types was observed. The detection limits of our ERA assays were 100 and 101 copies/µl for HPV16 and 18 respectively, which were comparable to those of the real-time PCR assay. Assessment of the clinical performance of the ERA assays using 114 cervical tissue samples demonstrated that they are highly consistent with real-time PCR, the gold standard for HPV detection. This study demonstrated that ERA-based assays possess excellent sensitivity, specificity, and repeatability for HPV16 and HPV18 detection with great potential to become robust diagnostic tools in local hospitals and field studies.

Sputum Processing Method for Lateral Flow Immunochromatographic Assays to Detect Coronaviruses

  • Aram Kang;Minjoo Yeom;Hyekwon Kim;Sun-Woo Yoon;Dae-Gwin Jeong;Hyong-Joon Moon;Kwang-Soo Lyoo;Woonsung Na;Daesub Song
    • IMMUNE NETWORK
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    • 제21권1호
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    • pp.11.1-11.10
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    • 2021
  • Coronavirus causes an infectious disease in various species and crosses the species barriers leading to the outbreak of zoonotic diseases. Due to the respiratory diseases are mainly caused in humans and viruses are replicated and excreted through the respiratory tract, the nasal fluid and sputum are mainly used for diagnosis. Early diagnosis of coronavirus plays an important role in preventing its spread and is essential for quarantine policies. For rapid decision and prompt triage of infected host, the immunochromatographic assay (ICA) has been widely used for point of care testing. However, when the ICA is applied to an expectorated sputum in which antigens are present, the viscosity of sputum interferes with the migration of the antigens on the test strip. To overcome this limitation, it is necessary to use a mucolytic agent without affecting the antigens. In this study, we combined known mucolytic agents to lower the viscosity of sputum and applied that to alpha and beta coronavirus, porcine epidemic diarrhea virus (PEDV) and Middle East respiratory syndrome coronavirus (MERS-CoV), respectively, spiked in sputum to find optimal pretreatment conditions. The pretreatment method using tris(2-carboxyethyl)phosphine (TCEP) and BSA was suitable for ICA diagnosis of sputum samples spiked with PEDV and MERS-CoV. This sensitive assay for the detection of coronavirus in sputum provides an useful information for the diagnosis of pathogen in low respiratory tract.

중년여성의 화병과 상지관절동통에 관한 문화기술지 (An Ethnographic Study on Middle aged Women's Hwa-Byung with Upper Limb Arthropathy)

  • 김미영
    • 동서간호학연구지
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    • 제13권2호
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    • pp.160-169
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    • 2007
  • Background: Hwa-Byung is known as a specific Korean cultural syndrome which corresponds to DSM-IV(MMPI). Some Korean women who have experienced heart aching anger(Hwa-Byung) complain physical pains as well as psychological problems. As for these physical pains, upper limb arthropathy(e.g. golf elbow pains, tennis elbow pains, or shoulder-joint pains) have not been paid attentions. In spite of not having done her excessive physical endeavor or exercise, some Korean middle aged women complain those arthropathy pains. And they go round orthopedics, pain clinics, and oriental medicine clinics. Purpose: This study was practiced in Severance Oriental Medicine Clinic. The oriental medicine doctor had a question about the major origin of upper limb pains which were not caused by excessive physical endeavor. To answer the question, this study has been practiced. In the process of interview with some those women, the major cause of those syndromes has been revealed as Hwa-Byung. The purpose of this study is to discover the meanings of the women's life who have been experienced Hwa-Byung with upper limb arthropathy. Results: These upper limb arthropathy can be explained by meridian theory. Shoulder-joint pain and golf elbow with Hwabyung can be explained by Heart meridian of hand-shoyin and the points of these pains are in the flow of this meridian. Tennis elbow with Hwabyung can be explained by Small intestine meridian of hand-taiyang and this point is in the flow of this meridian. The results of interview with 9 middle aged women was analyzed and interpreted according to Spradley's method of ethnography. The analysis revealed three core cultural themes : 1) There are certainly external cause to provoke Hwa-Byung. A patricentric family system, husband's playing around with another woman, cruel treatment by husband's family, or financial failure may be present anteriorly. 2) The chief existing condition is the discord between husband and wife. The stoppage of mutual communication, lacking in understanding, unfeeling, heartless, or unsympathetic is an major phenomenon of married life. So the important factor is not the sexual relations or problems but the discords of communication. 3) The feeling of anger, the sense of nihility, the desire to escape, and the effort to forgiveness coexist together. At a glance, they seemed to be a process. For example, anger seemed to present at first, then nihility seemed at second, then escape seemed at third, and then forgiveness seemed at last. But at point of visiting clinic to be treated, they are mixed up together as if in a jumble.

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광주, 본촌지역의 지하수의 수화학적 특성과 오염 (Chemical Characteristics and Pollution of Groundwater in the Ponchon Area, Kwangju)

  • 양해근;김인수;최희철;김정우
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제6권4호
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    • pp.83-95
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    • 2001
  • 본 연구에서는 광주 본촌분지를 대상으로 지하수의 오염현황을 분석하고, 수문지질구조와 수두의 분포 그리고 지하수의 수화학적 조성으로부터 오염기구를 검토하였다. 그 결과는 다음과 같다. 분지의 수두분포는 대체적으로 지형면을 반영하고 있으나, 과잉양수에 의한 지하수 유동계의 변형이 나타나고 있다. 농경지와 주거지가 혼재된 분지 북부에서는 Cl와 EC, Na, $NO_3$농도가 비교적 높았으며, 공업단지가 입지한 분지 남쪽에서는 $HCO_3$$Ca^{2+}$, $Mg^{2+}$, Zn이 상대적으로 높은 농도를 나타냈다. Cl-과 N $O_3$농도에 의한 오염은 생활.공장폐수에 의한 것으로 추정된다. 그리고, Cl의 경우에는 특정 오염원을 기점으로 하천수계를 따라 오염물질이 확산되는 양상을 보이고 있으며, 오염원의 분포와 농도분포를 고려할 때 오염물질의 수평 분산보다는 공단지역의 과잉양수에 의한 지하수위의 저하로 수직이동이 더 크게 작용하고 있다고 볼 수 있다. 이상으로부터 공단지역에서의 지하수 과잉양수가 지속될 경우, 지형면을 따라 형성된 유동계가 더욱 왜곡되고, 지하수위의 급격한 저하는 분지 북부지역에 까지 미치게 될 것이다. 더욱이 분지 북부의 생활 공장폐수에 의한 염수화 현상 또는 질소오염은 분지 전역으로 확산될 것은 자명하다.현상 또는 질소오염은 분지 전역으로 확산될 것은 자명하다.

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Sedimentary Facies and Architecture of a Gigantic Gravelly Submarine Channel System in a Cretaceous Foredeep Trough (the Magallanes Basin, Southern Chile)

  • Sohn, Young Kwan;Jo, Hyung Rae;Woo, Jusun;Kim, Young-Hwan G.;Choe, Moon Young
    • Ocean and Polar Research
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    • 제39권2호
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    • pp.85-106
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    • 2017
  • The Lago Sofia conglomerate in southern Chile is a deep-marine gravelly deposit, which is hundreds of meters thick and kilometers wide and extends laterally for more than 100 km, filling the foredeep trough of the Cretaceous Magallanes Basin. For understanding the depositional processes and environments of this gigantic deep-sea conglomerate, detailed analyses on sedimentary facies, architecture and paleoflow patterns were carried out, highlighting the differences between the northern (Lago Pehoe and Lago Goic areas) and southern (Lago Sofia area) parts of the study area. The conglomerate bodies in the northern part occur as relatively thin (< 100 m thick), multiple units intervened by thick mudstone-dominated sequences. They show paleoflows toward ENE and S to SW, displaying a converging drainage pattern. In the southern part, the conglomerate bodies are vertically interconnected and form a thick (> 400 m thick) conglomerate sequence with rare intervening fine-grained deposits. Paleoflows are toward SW. The north-to-south variations are also distinct in sedimentary facies. The conglomerate bodies in the southern part are mainly composed of clast-supported conglomerate with sandy matrix, which is interpreted to be deposited from highly concentrated bedload layers under turbidity currents. Those in the northern part are dominated by matrix- to clast-supported conglomerate with muddy matrix, which is interpreted as the products of composite mass flows comprising a turbidity current, a gravelly hyperconcentrated flow and a mud-rich debris flow. All these characteristics suggest that the Lago Sofia conglomerate was formed in centripetally converging submarine channels, not in centrifugally diverging channels of submarine fans. The tributaries in the north were dominated by mass flows, probably affected by channel-bank failures or basin-marginal slope instability processes. In contrast, the trunk channel in the south was mostly filled by tractive processes, which resulted in the vertical and lateral accretion of gravel bars, deposition of gravel dunes and filling of scours and channels, similar to deposits of terrestrial gravel-bed rivers. The trunk channel developed along the axis of foredeep trough and its confinement within the trough is probably responsible for the thick, interconnected channel fills. The large-scale architecture of the trunk-channel fills shows an eastward offset stacking pattern, suggesting that the channel migrated eastwards most likely due to the uplift of the Andean Cordillera.

RCP 기후변화 시나리오에 따른 임하댐 유역의 미래 수문순환 전망 (Assessment of Climate Change Impact on Imha-Dam Watershed Hydrologic Cycle under RCP Scenarios)

  • 장선숙;안소라;조형경;김성준
    • 한국지리정보학회지
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    • 제18권1호
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    • pp.156-169
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    • 2015
  • 본 연구는 SWAT(Soil and Water Assessment Tool) 모형을 이용하여 임하댐 유역($1,355.5km^2$)을 대상으로 RCP(AR5) 기후변화 시나리오에 따른 미래 수문순환 영향을 평가하였다. 3지점의 실측된 유출량을 활용하여 모형의 보정(2002~2007년) 및 검증(2008~2013년)을 실시하였다. 검 보정 결과 결정계수($R^2$)는 0.70~0.85로, Nash-Sutcliffe 모형 효율(NSE)은 0.67~0.82로 분석되어 신뢰성 있는 유출량 모의 결과를 나타내었다. 기후변화 시나리오는 기상청에서 제공하는 HadGEM3-RA 모형의 RCP 4.5 및 8.5 시나리오를 수집하여, 과거 34년(1980-2013, baseline period)의 기상자료를 기준으로 편이보정(Bias Correction)하여 SWAT모형에 적용하였다. 기후변화 분석 결과 강수량과 평균기온이 10.8%, $4.9^{\circ}C$ 증가하였으며, 강수량과 기온의 증가로 증발산 11.2%, 토양수분 1.9%, 지표유출 10.0%, 중간유출 12.1%, 회귀유출 18.2%이 각각 증가함에 따라 총 하천유출량이 11.2% 증가하였다.