• 제목/요약/키워드: Quantitative Approaches

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Quantitative Approaches for the Determination of Volatile Organic Compounds (VOC) and Its Performance Assessment in Terms of Solvent Types and the Related Matrix Effects

  • Ullah, Md. Ahsan;Kim, Ki-Hyun;Szulejko, Jan E.;Choi, Dal Woong
    • Asian Journal of Atmospheric Environment
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    • 제11권1호
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    • pp.1-14
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    • 2017
  • For the quantitative analysis of volatile organic compounds (VOC), the use of a proper solvent is crucial to reduce the chance of biased results or effect of interference either in direct analysis by a gas chromatograph (GC) or with thermal desorption analysis due to matrix effects, e.g., the existence of a broad solvent peak tailing that overlaps early eluters. In this work, the relative performance of different solvents has been evaluated using standards containing 19 VOCs in three different solvents (methanol, pentane, and hexane). Comparison of the response factor of the detected VOCs confirms their means for methanol and hexane higher than that of pentane by 84% and 27%, respectively. In light of the solvent vapor pressure at the initial GC column temperature ($35^{\circ}C$), the enhanced sensitivity in methanol suggests the potential role of solvent vapor expansion in the hot injector (split ON) which leads to solvent trapping on the column. In contrast, if the recurrent relationships between homologues were evaluated using an effective carbon number (ECN) additivity approach, the comparability assessed in terms of percent difference improved on the order of methanol (26.5%), hexane (6.73%), and pentane (5.24%). As such, the relative performance of GC can be affected considerably in the direct injection-based analysis of VOC due to the selection of solvent.

다구찌 기법을 적용한 다기준 의사결정 모형의 신뢰성 향상에 관한 연구 (- A Study on Improving Reliability for Multiple Criteria Decision Making Using Taguchi Method -)

  • 허준영;박명규
    • 대한안전경영과학회지
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    • 제6권3호
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    • pp.249-273
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    • 2004
  • Finding an optimal solution in MADN[(Multi-Attribute Decision-Making) problems is difficult, when the number of alternatives, or that of attributes is relatively large Most of the existing mathematical approaches arrive at a final solution on the basis of many unrealistic assumptions, without reflecting the decision-maker's preference structure exactly. In this paper we suggest a model that helps us find a group consensus without assessing these parameters in specific cardinal values. Therefore, This research provides a comprehensive Decision Making of the theory and methods applicable to the analysis of decisions that involve risk and multiple criteria attributes. after, The emphasis of the procedure will be on developments from the fields of decisions analysis and utility theory of Taguchi Method. This theoretical development will be illustrated through the discussion of several real-world application and a case study. When the multiple number of decision makers are involved in the decision making procedure, the problem of uncertainties invariably occurs, because of the different views between them. In this paper, New decision making model using Taguchi Method is applied to effectively model the multi-attribute-decision making(MADM) procedure in the uncertainties dominated two area(quantitative and qualitative factors), Quantitative factors evaluation is used Loss Function of Taguchi, qualitative factors evaluation is used 50 ratio by each specialist. thus it can be used for aiding of preferable alternative. as a result, We will be proved efficiency about New decision making model of applied Taguchi Method with Analytical presentation of all the expecting outcomes when a specific strategy or an alternative plan is selected under expecting future environment.

공간구문론을 활용한 아파트단지 외부공간의 시기별 접근성 변화 분석 (Chronological Analysis of the Accessibility Change of Outdoor Space in Apartment Complexes Using Space Analysis Method)

  • 최재필;변나향;김민석
    • 한국주거학회논문집
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    • 제21권4호
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    • pp.1-9
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    • 2010
  • Since the active enhancement of large-scale apartment development in 1970, apartment complexes in Korea have shown considerable changes throughout, with respect to its planning and design. Depending on the government legislations, and economical and social issues of its time, apartments have been designed to respond to varying demands of the society; from minimal unit design to overall masterplan. As existing researches regarding development of apartment planning are conducted in individual and distinct manner, not only is it difficult to find cases of an overall critical analysis of apartment complexes, it is also rare to look for research that deals with a greater urban context, nor the geographical location of the site. With specific focus on apartments in the metropolitan, the focus of this research lies in critically analyzing the qualities of outdoor spaces within an apartment complex, its generational change and interpreting the value it holds for the society. With regards to analyzing its outdoor features, the core of this study deals with applying space syntax, based on the configurational properties of spatial constituents. The results of this research have some implications that the accessibility change of apartment outdoor spaces was examined through quantitative analysis, and the changes of it by time were clarified in detail. And objective and quantitative approaches were employed for an alternative to the methods used in existing related researches.

해안 매립지 탄성파 탐사 (Quantitative assessment of reclamation-dams from the sea by using combined seismic methods)

  • 김중열
    • 한국지구물리탐사학회:학술대회논문집
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    • 한국지구물리탐사학회 2002년도 정기총회 및 제4회 특별심포지움
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    • pp.85-100
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    • 2002
  • 본 논문의 주요 내용은 텔레뷰어와 탄성파 토모그래피에 바탕을 둔 하나의 물리탐사 병합 기술에 의해 연안 매립지 조성을 위해 착수되는 사석댐의 하부구조를 고분해능으로 규명하는 데 있다. 해성점토 위에 투하된 사석은 그 하중에 의해 침하되어 하나의 사석층을 이루게 되며 그 침하 심도는 해성점토의 두께 등 여러 가지 요인에 의해 달리하고 있다. 여기서 관심의 초점은 무엇보다 사석량 산출을 위해 필요한 사석층 경계면이다. 그런데, 조사의 정확도를 기대 수준으로 끌어올리기 위해 상기 두 기법 본연 (상용되는)의 기능만으로는 거의 불가능하다고 할 수 있다. 여기에는 각 기법의 고유 기능을 바탕으로 그에 따른 새로운 측정 및 분석기법 개발이 불가피하다. 본 논문에는 우선 이에 대한 적절한 측정 기법을 소개하고 있으며 나아가서 사석층 경계면 판단을 위한 다양한 분석 기법을 제시하고 있다.

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건설 프로젝트 효율적 성과관리를 위한 핵심 지표 체계 구축 (Developing Measurement System for Key Performance Indicators on Building Construction Projects)

  • 차희성;김태경
    • 한국건설관리학회논문집
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    • 제9권4호
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    • pp.120-130
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    • 2008
  • 건설산업의 핵심성과는 프로젝트가 추구하는 목표, 즉, 비용, 시간, 품질, 안전, 환경 등의 기준을 어느 정도 달성했는지로 평가할수 있다. 그러나, 프로젝트 기반산업이라고 할 수 있는 건설산업의 경우, 성과에 대한 명확한 정의체계가 부재하고, 성과측정에 대한 표준화된 절차와 관리 방식이 구축되어 있지 않아서 프로젝트의 성과를 객관적이고 합리적으로 평가하기가 매우 어려운 것이 현실이다. 본 연구에서는 프로젝트 차원의 성과에 대한 정의 및 기준을 설정하고, 각 성과기준 댈 지표 산출 방식을 개발한 후, 이들 지표를 통해 정량적으로 프로젝트의 성과를 산출할 수 있는 방법론을 제안하고자 한다. 제안된 성과측정 방법론에 입각하여, 실제 사례 프로젝트를 수집하고, 이들을 비교 분석해 봄으로써, 향후 건설 프로젝트에 적용가능 한지에 대한 평가를 실시하였다. 이를 통해 특정한 건설 프로젝트는 상호 비교가능한 지표의 형태로 변환될 수 있으며, 개별프로젝트의 성과를 종합적으로 분석하는 것이 가능해진다. 또한, 건설 프로젝트 관련자로 하여금 성과에 입각한 관리를 가능하도록 유도하여 건설 프로젝트의 효율성을 진작시키는데 큰 역할을 담당할 수 있을 것으로 기대한다.

라디오믹스 기반 직장암 수술 위험도 예측을 위한 MRI 반자동 선택 바이오마커 검증 연구 (A Study on MRI Semi-Automatically Selected Biomarkers for Predicting Risk of Rectal Cancer Surgery Based on Radiomics)

  • 백영서;김영재;전영배;황태식;백정흠;김광기
    • 대한의용생체공학회:의공학회지
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    • 제44권1호
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    • pp.11-18
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    • 2023
  • Currently, studies to predict the risk of rectal cancer surgery select MRI image slices based on the clinical experience of surgeons. The purpose of this study is to semi-automatically select and classify 2D MRI image slides to predict the risk of rectal cancer surgery using biomarkers. The data used were retrospectively collected MRI imaging data of 50 patients who underwent laparoscopic surgery for rectal cancer at Gachon University Gil Medical Center. Expert-selected MRI image slices and non-selected slices were screened and radiomics was used to extract a total of 102 features. A total of 16 approaches were used, combining 4 classifiers and 4 feature selection methods. The combination of Random Forest and Ridge performed with a sensitivity of 0.83, a specificity of 0.88, an accuracy of 0.85, and an AUC of 0.89±0.09. Differences between expert-selected MRI image slices and non-selected slices were analyzed by extracting the top five significant features. Selected quantitative features help expedite decision making and improve efficiency in studies to predict risk of rectal cancer surgery.

국가지정 입원치료병상에 입실한 COVID-19 환자를 돌보는 간호사의 업무분석 (An Analysis of Tasks of Nurses Caring for Patients with COVID-19 in a Nationally-Designated Inpatient Treatment Unit)

  • 정민호;김문숙;이주연;이경이;박연환
    • 대한간호학회지
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    • 제52권4호
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    • pp.391-406
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    • 2022
  • Purpose: The purpose of this study was to provide foundational knowledge on nursing tasks performed on patients with COVID-19 in a nationally-designated inpatient treatment unit. Methods: This study employs both quantitative and qualitative approaches. The quantitative method investigated the content and frequency of nursing tasks for 460 patients (age ≥ 18 y, 57.4% men) from January 20, 2020, to September 30, 2021, by analyzing hospital information system records. Qualitative data were collected via focus group interviews. The study involved interviews with three focus groups comprising 18 nurses overall to assess their experiences and perspectives on nursing care during the pandemic from February 3, 2022, to February 15, 2022. The data were examined with thematic analysis. Results: Overall, 49 different areas of nursing tasks (n = 130,687) were identified based on the Korean Patient Classification System for nurses during the study period. Among the performed tasks, monitoring of oxygen saturation and measuring of vital signs were considered high-priority. From the focus group interview, three main themes and eleven sub-themes were generated. The three main themes are "Experiencing eventfulness in isolated settings," "All-around player," and "Reflections for solutions." Conclusion: During the COVID-19 pandemic, it is imperative to ensure adequate staffing levels, compensation, and educational support for nurses. The study further propose improving guidelines for emerging infectious diseases and patient classification systems to improve the overall quality of patient care.

Characterization of Purple-discolored, Uppermost Leaves of Soybean; QTL Mapping, HyperspectraI Imaging, and TEM Observation

  • JaeJin Lee;Jeongsun Lee;Seongha Kwon;Heejin You;Sungwoo Lee
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2022년도 추계학술대회
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    • pp.187-187
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    • 2022
  • Purple-discoloration of the uppermost leaves has been observed in some soybean cultivars in recent years. The purpose of this study was to characterize the novel phenotypic changes between the uppermost and middle leaves via multiple approaches. First, quantitative trait loci mapping was conducted to detect loci associated with the novel phenotype using 85 recombinant inbred lines (RILs) of the 'Daepung' × PI 96983 population. 180K SNP data, a major quantitative trait locus (QTL) was identified at around 60 cM of chromosome 6, which accounts for 56% of total phenotypic variance. The genomic interval is about ~700kb, and a list of annotated genes includes the T-gene which is known to control pubescence and seed coat color and is presumed to encode flavonoid 35-hydroxylase (F3'H). Based on Hyperspectral imaging, the reflectance at 528-554 nm wavelength band was extremely reduced in the uppermost leaves compared to the middle (green leaves), which is presumed die to the accumulation of anthocyanins. In addition, purple-discolored leaf tissues were observed and compared to normal leaves using a transmission electronic microscope (TEM). Base on observations of the cell organelles, the purple-discolored uppermost leaves had many pigments formed in the epidermal cells unlike the normal middle leaves, and the cell wall thickness was twice as thick in the discolored leaves. The thickness of the thylakoid layer in the chloroplast the number of starch grains, the size of starch all decreased in the discolored leaves, while the number of plastoglobule and mitochondria increased.

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Comparison of microbial molecular diagnosis efficiency within unstable template metagenomic DNA samples between qRT-PCR and chip-based digital PCR platforms

  • Dongwan Kim;Junhyeon Jeon;Minseo Kim;Jinuk Jeong;Young Mok Heo;Dong-Geol Lee;Dong Keon Yon;Kyudong Han
    • Genomics & Informatics
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    • 제21권4호
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    • pp.52.1-52.10
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    • 2023
  • Accurate and efficient microbial diagnosis is crucial for effective molecular diagnostics, especially in the field of human healthcare. The gold standard equipment widely employed for detecting specific microorganisms in molecular diagnosis is quantitative real-time polymerase chain reaction (qRT-PCR). However, its limitations in low metagenomic DNA yield samples necessitate exploring alternative approaches. Digital PCR, by quantifying the number of copies of the target sequence, provides absolute quantification results for the bacterial strain. In this study, we compared the diagnostic efficiency of qRT-PCR and digital PCR in detecting a particular bacterial strain (Staphylococcus aureus), focusing on skin-derived DNA samples. Experimentally, specific primer for S. aureus were designed at transcription elongation factor (greA) gene and the target amplicon were cloned and sequenced to validate efficiency of specificity to the greA gene of S. aureus. To quantify the absolute amount of microorganisms present on the skin, the variable region 5 (V5) of the 16S rRNA gene was used, and primers for S. aureus identification were used to relative their amount in the subject's skin. The findings demonstrate the absolute convenience and efficiency of digital PCR in microbial diagnostics. We suggest that the high sensitivity and precise quantification provided by digital PCR could be a promising tool for detecting specific microorganisms, especially in skin-derived DNA samples with low metagenomic DNA yields, and that further research and implementation is needed to improve medical practice and diagnosis.

해상교통환경 위험요소의 상대적 중요도를 고려한 목포항 및 진입수로의 위험도 평가 (Evaluation on Risk at the Port of Mokpo and its Approaches based on Relative Importance of Risk Factors for Marine Traffic Environment)

  • 이홍훈;김철승
    • 해양환경안전학회지
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    • 제19권4호
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    • pp.375-381
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    • 2013
  • 해상교통환경의 위험도를 평가하기 위해서는 위험도를 구성하고 있는 위험요소들을 명확히 식별하고, 식별된 위험요소들을 평가할 수 있는 기준을 마련하여야 한다. 한편 이러한 각 위험요소들의 위험수준의 합으로 전체 위험도를 나타낼 수 있으므로, 각 위험요소가 전체 위험도에서 차지하는 비중인 상대적 중요도가 분석되어야 한다. 본 연구는 선행연구에서 국내 외 해상교통환경 위험도 평가모델들의 검토를 통하여 제시된 국내 해상교통환경의 위험도를 구성하는 20가지 위험요소와 평가기준 및 해상교통전문가 집단에 의한 설문조사를 통하여 계층분석적 의사결정법으로 분석한 각 위험요소의 상대적 중요도를 바탕으로, 국내 목포항 및 그 진입수로에 대한 해상교통환경의 위험도를 평가하였다. 목포항 및 그 진입수로는 비교평가를 위하여 총 4개의 해역으로 구분하여 분석하였으며, 분석결과 위험요소 해수운동 복잡성 예인선 도선사 선박교통관제 등에서 위험수준이 높게 나타난 정등해 항로의 위험도가 가장 높게 평가되었다. 이러한 평가결과는 동일한 해역에서 본 연구와는 다른 정성적 혹은 정량적 위험도 분석기법을 이용한 연구들의 평가결과와 대체로 일치하였다.