• Title/Summary/Keyword: Importance ratio

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Landslide Susceptibility Mapping for 2015 Earthquake Region of Sindhupalchowk, Nepal using Frequency Ratio

  • Yang, In Tae;Acharya, Tri Dev;Lee, Dong Ha
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.34 no.4
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    • pp.443-451
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    • 2016
  • Globally, landslides triggered by natural or human activities have resulted in enormous damage to both property and life. Recent climatic changes and anthropogenic activities have increased the number of occurrence of these disasters. Despite many researches, there is no standard method that can produce reliable prediction. This article discusses the process of landslide susceptibility mapping using various methods in current literatures and applies the FR (Frequency Ratio) method to develop a susceptibility map for the 2015 earthquake region of Sindhupalchowk, Nepal. The complete mapping process describes importance of selection of area, and controlling factors, widespread techniques of modelling and accuracy assessment tools. The FR derived for various controlling factors available were calculated using pre- and post- earthquake landslide events in the study area and the ratio was used to develop susceptibility map. Understanding the process could help in better future application process and producing better accuracy results. And the resulting map is valuable for the local general and authorities for prevention and decision making tasks for landslide disasters.

Analysis Possibility of the Landslide Occurrence in Kangwon-Do using a High-resolution LiDAR-derived DEM (고해상도 항공라이다 DEM 해석을 통한 강원도 일원의 산사태 예측 가능성 분석)

  • Lee, Dong-Ha;Kim, Young-Seup;Suh, Yong-Cheol
    • Spatial Information Research
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    • v.17 no.3
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    • pp.381-387
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    • 2009
  • This study investigates the use of geomorphic analysis results obtained from high-resolution LiDAR-derived DEM. The results of analysis, slope angle and eigenvalue ratio (ER) were derived from the DEM for 3 landslide and 1 non-landslide occurrence area. Results of this study highlighted the importance of geomorphic analysis in characterizing landslide feature as well as the various contents in their future occurrence and activity. The relationship between the results of geomorphic analysis and landslides are well expressed in this paper.

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An Experimental Study of Underexpanded Moist Air Jet Impinging on a Flat Plate

  • Lee, D.W.;S.C. Baek;S.B. Kwon;Kim, H.D.
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2004.03a
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    • pp.768-773
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    • 2004
  • When a gas expands through a convergent nozzle in which the ratio of the ambient to the stagnation pressures is higher than that of the critical one, the issuing jet from the nozzle is underexpanded. If a flat plate is placed normal to the jet at a certain distance from the nozzle, a detached shock wave is formed at a region between the nozzle exit and the plate. In general, supersonic moist air jet technologies with nonequilibrium condensation are very often applied to industrial manufacturing processes. In spite of the importance in major characteristics of the supersonic moist air jets impinging to a solid body, its qualitative characteristics can not even know. In the present study, the effect of the nonequilibrium condensation on the underexpanded moist air jet impinging on a vertical flat plate is investigated experimentally. Flow visualization and impact pressure measurement are performed for various relative humidities and flat plate positions. The obtained results show the plate shock and Mach disk are dependent on the nozzle pressure ratio and the relative humidity, but for a given nozzle pressure ratio, the diameters of the plate shock and Mach disk depend on the stagnation relative humidity. The impact pressure deviation from the flow of without condensation is large, as the relative stagnation humidity increases.

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Novel aspects of elastic flapping wing: Analytical solution for inertial forcing

  • Zare, Hadi;Pourtakdoust, Seid H.;Bighashdel, Ariyan
    • Advances in aircraft and spacecraft science
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    • v.5 no.3
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    • pp.335-348
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    • 2018
  • The structural dynamics (SD) behavior of Elastic Flapping Wings (EFWs) is investigated analytically as a novel approach in EFWs analysis. In this regard an analytical SD solution of EFW undergoing a prescribed rigid body motion is initially derived, where the governing equations are expressed in modal space. The inertial forces are also analytically computed utilizing the actuator induced acceleration effects on the wing structure, while due to importance of analytical solution the linearity assumption is also considered. The formulated initial-value problem is solved analytically to study the EFW structural responses, where the effect of structure-actuator frequency ratio, structure-flapping frequency ratio as well as the structure damping ratio on the EFW pick amplitude is analyzed. A case study is also simulated in which the wing is modeled as an elastic beam with shell elements undergoing a prescribed sinusoidal motion. The corresponding EFW transient and steady response in on-off servo behavior is investigated. This study provides a conceptual understanding for the overall EFW SD behavior in the presence of inertial forces plus the servo dynamics effects. In addition to the substantial analytical results, the study paves a new mathematical way to better understanding the complex role of SD in dynamic EFWs behavior. Specifically, similar mathematical formulations can be carried out to investigate the effect of aerodynamics and/or gravity.

Capital Structure and Trade-Off Theory: Evidence from Vietnam

  • KHOA, Bui Thanh;THAI, Duy Tung
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.1
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    • pp.45-52
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    • 2021
  • The capital structure is one of the hot financial topics among researchers and scholars. Its importance comes from the fact that capital structure is closely related to companies' ability to meet different stakeholders' needs. A suitable capital structure will boost the business and create a competitive advantage in the context of fierce competition. Many companies choose an optimal debt level based on the trade-off between interest and debt costs. This study aimed to test the existence of trade-off theory in capital structure, the case of Vietnam's real estate companies, which are growing very fast recently. Instead of considering constant optimal leverage to test the trade-off model, we take advantage of the dynamic capital structure determined by growth opportunities, profitability, tax incentives, tangibility, liquidity, and firm size. The dynamic panel data regression was estimated by the system Generalized Method of Moment (Sys-GMM). The empirical evidence showed that real estate companies listed in the Vietnamese stock market might change their leverage toward a target capital structure determined by influential factors in a long-term perspective. In particular, the debt-to-asset ratio will change by approximately 14 percent, positively, in response to the difference between the current debt-to-asset ratio and the dynamic target debt-to-asset ratio.

Exploring geometric and kinematic correspondences between gear-based crank mechanism and standard reciprocating crankshaft engines: An analytical study

  • Amir Sakhraoui;Fayza Ayari;Maroua Saggar;Rachid Nasri
    • Structural Engineering and Mechanics
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    • v.90 no.1
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    • pp.97-106
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    • 2024
  • This paper presents a significant contribution to aided design by conducting an analytical examination of geometric links with the aim of establishing criteria for assessing an analogy measure of the extrinsic geometric and kinematic characteristics of the Variable Compression Ratio (VCR) engine with a Geared Mechanism (GBCM) in comparison to the existing Fixed Compression Ratio (FCR) engine with a Standard-Reciprocating Crankshaft configuration. Employing a mechanical approach grounded in projective computational methods, a parametric study has been conducted to analyze the kinematic behavior and geometric transformations of the moving links. The findings indicate that in order to ensure equivalent extrinsic behavior and maintain consistent input-output performance between both engine types, precise adjustments of intrinsic geometric parameters are necessary. Specifically, for a VCR configuration compared to an FCR configuration, regardless of compression ratio and gearwheel radius, for the same crankshaft ratios and stroke lengths, it is imperative to halve lengths of connecting rods, and crank radius. These insights underscore the importance of meticulous parameter adjustment in achieving comparable performance across different engine configurations, offering valuable implications for design optimization.

Study on the Relationship Between 12Meridians Flow and Facial Expressions by Emotion (감정에 따른 얼굴 표정변화와 12경락(經絡) 흐름의 상관성 연구)

  • Park, Yu-Jin;Moon, Ju-Ho;Choi, Su-Jin;Shin, Seon-Mi;Kim, Ki-Tae;Ko, Heung
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.26 no.2
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    • pp.253-258
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    • 2012
  • Facial expression was an important communication methods. In oriental medicine, according to the emotion the face has changed shape and difference occurs in physiology and pathology. To verify such a theory, we studied the correlation between emotional facial expressions and meridian and collateral flow. The facial region divided by meridian, outer brow was Gallbladder meridian, inner brow was Bladder meridian, medial canthus was Bladder meridian, lateral canthus was Gallbladder meridian, upper eyelid was Bladder meridian, lower eyelid was Stomach meridian, central cheeks was Stomach meridian, lateral cheeks was Small intestine meridian, upper and lower lips, lip corner, chin were Small and Large intestine meridian. Meridian and collateral associated with happiness was six. This proves happiness is a high importance on facial expression. Meridian and collateral associated with anger was five. Meridian and Collateral associated with fear and sadness was four. This shows fear and sadness are a low importance on facial expression than different emotion. Based on yang meridian which originally descending flow in the body, the ratio of anterograde and retrograde were happiness 3:4, angry 2:5, sadness 5:3, fear 4:1. Based on face of the meridian flow, the ratio of anterograde and retrograde were happiness 5:2, angry 3:4, sadness 3:5, fear 4:1. We found out that practical meridian and collateral flow change by emotion does not correspond to the expected meridian and collateral flow change by emotion.

Importance of Neutrophil/Lymphocyte Ratio in Prediction of PSA Recurrence after Radical Prostatectomy

  • Gazel, Eymen;Tastemur, Sedat;Acikgoz, Onur;Yigman, Metin;Olcucuoglu, Erkan;Camtosun, Ahmet;Ceylan, Cavit;Ates, Can
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.5
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    • pp.1813-1816
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    • 2015
  • Background: The aim of this study was to research the importance of the neutrophil to lymphocyte ratio (NLR) in prediction of PSA recurrence after radical prostatectomy, which has not been reported so far. Materials and Methods: The data of 175 patients who were diagnosed with localised prostate cancer and underwent retropubic radical prostatectomy was retrospectively examined. Patient pre-operative hemogram parameters of neutrophil count, lymphocyte count and NLR were assessed. The patients whose PSAs were too low to measure after radical prostatectomy in their follow-ups, and then had PSAs of 0,2 ng/mL were considered as patients with PSA recurrence. Patients with recurrence made up Group A and patients without recurrence made up Group B. Results: In terms of the power of NLR value in distinguishing recurrence, the area under OCC was statistically significant (p<0.001) .The value of 2.494 for NLR was found to be a cut-off value which can be used in order to distinguish recurrence according to Youden index. According to this, patients with a higher NLR value than 2.494 had higher rates of PSA recurrence with 89.7% sensitivity and 92.6% specificity. Conclusions: There are certain parameters used in order to predict recurrence with today's literature data.We think that because NLR is easy to use in clinics and inexpensive, and also has high sensitivity and specificity values, it has the potential to be one of the parameters used in order to predict biochemical recurrence in future.

Further evidence of changing stability of atmosphere and climate on spallation product measurement (핵파쇄잔류물질의 지표면도달량 측정결과를 이용한 기후와 대기구조의 불안정변화에 미치는 영향)

  • Hartwig, Sylvius
    • Proceedings of the Korean Institute of Industrial Safety Conference
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    • 2003.05a
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    • pp.17-20
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    • 2003
  • In a recent paper (Hartwig, ms.) I have shown that it is possible to understand and discuss the changing Austausch (i.e., exchange of air parcels between different atmospheric layers) between the stratosphere and troposphere by means of long-term measurement on series of spallation products. It is well known (Friend 1961; Muet et al. 1966, Hartwig et al. 1969) that there is a seasonal pattern in the 7Be concentration of ground-level air with a maximum during May-June. This maximum is caused by enhanced exchange processes between the atmospheric compartments of the stratosphere and troposphere during this interval. Generally, those exchange processes are a consequence of stability and dynamics of the atmospheric compartments, which themselves result from, among other factors, the distribution of the heat sources in those compartments, namely the ground and the ozone layer. Because of the growing importance of anthropogenic infrared-active gases in the atmosphere, it is to be expected that the relative importance of those original, naturally occurring heat sources will be of lesser significance, thus altering the Austausch. And indeed, it has been shown (Hartwig, ms.) by considering the ratio of the annual maximum and minimum during a 28-yr period of 7Be ground-level concentration at Braunschweig, Germany (10$^{\circ}$33'E, 52$^{\circ}$17'N) (Kolb 1992; Wershofen 1993), that there is a steady decline in that ratio, thus indicating alteration of atmospheric Austausch within the last three decades.(omitted)

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Distribution and Habitat Chracteristics of Lonicera japonica Thunb. in the Inland and the Seashore Areas of Korea

  • Kim, Seong-Min;Shin, Dong-Il;Yoon, Seong-Tak;Song, Hong-Seon
    • Korean Journal of Medicinal Crop Science
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    • v.15 no.5
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    • pp.362-366
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    • 2007
  • This study was conducted to evaluate the status of habitat distribution, environmental characteristics and plant species growing with Lonicera japonica in its habitats. In the distribution of plant coverage below 30%, it was 84.6% in the inland area and 80.7% in the seashore area. There was similar coverage in both inland and seashore areas. But the average relative coverage in the seashore area was 26.1%, which is a little higher than that of the inland area (22.5%). In the habitats, both inland and seashore areas showed a high distribution ratio below 10 degrees. But among them, inland areas showed a high distribution ratio (62.4%) below 10 degrees, which was about twice as much as the seashore areas (32.2%). Habitat distribution was most often found on the southern slopes in both inland and seashore areas. The average soil pH of Lonicera japonica habitat was 5.2 in the inland areas and 6.9 in the seashore areas. Also, the seashore areas showed little content of $P_2O_5$, but high content of K, Mg, Na on the other hand compared to the inland area. Miscanthus sinensis was the highest importance value (16.4) among plants growing with Lonicera japonica in their habitats in both inland and seashore areas. But in the inland areas, Artemisia princeps showed the highest importance value, and Miscanthus sinensis was the highest in the seashore areas.