• Title/Summary/Keyword: Stability Indices

Search Result 214, Processing Time 0.022 seconds

Analyses on Management Situations of 'A' and 'B' Corporations as the Environment-Friendly Agricultural Organization at Asan (친환경농업 A영농법인과 B농업회사법인의 경영실태 분석- 충남 아산의 친환경 생산자조직을 사례로 -)

  • Kim, Ho
    • Korean Journal of Organic Agriculture
    • /
    • v.30 no.4
    • /
    • pp.471-483
    • /
    • 2022
  • This study analyzed management situations of two organizations that have produced environment-friendly agricultural and processed meat products. 'A' farming corporation sells environment-friendly agricultural products like as grains, vegetables, fruits and processing foods. 'B' agricultural corporation processes and sells environment-friendly processed meat products, specially organic and antibiotic-free beef products. Recently, members and production areas of 'A' farming corporation have decreased because of their aging and labor shortage. And Indices for the management analysis are stability ratio, activity ratio and profitability ratio. Stability ratio indices are debt ratio, net worth ratio, fixed ratio and current ratio. Activity ratio ones include fixed assets turnover and net worth turnover. And profitability ratio is showed through return on investment, net return on sales and return on equity.

The Effect of Hull Appendages on Maneuverability of Naval Ship by Sensitivity Analysis (민감도 해석을 통한 선체 부가물이 함정의 조종성능에 미치는 영향 분석)

  • Kim, Dae Hyuk;Rhee, Key-Pyo;Kim, Nakwan
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.51 no.2
    • /
    • pp.154-161
    • /
    • 2014
  • Naval ships have hull appendages which are more exposed to the outside because of its small block coefficient compared with commercial ships. These exposed hull appendages like skeg, strut and shaft line affect the maneuverability of a ship. The effect of hull appendages has considered at initial design stage to estimate more accurate maneuverability. In this paper, sensitivity analysis is used to analyze the effect on maneuverability by hull appendages. 3 DOF maneuvering equations based on Mathematical Modelling Group (MMG) model are used and propeller & rudder model are modified to reflect the characteristics of twin propeller & twin rudder. Numerical maneuvering simulations (Turning test, Zig-zag test) for benchmark naval vessel, David Taylor Model Basin (DTMB) 5415 are performed. In every simulation, it is calculated that stability indices and maneuverability characteristics (Tactical Dia., Advance, 1st Overshoot, Time of complete cycle) with respect to the parameters (area times lift coefficient slope, attachment location) of hull appendages. As a result, two regression formulas are established. One is the relation of maneuverability characteristics and stability indices and the other is the relation of stability indices and hull appendages.

A Novel Method of Clustering Critical Generator by using Stability Indices and Energy Function (안정도 지수와 에너지 마진을 이용한 불안정 발전기의 clustering 법)

  • Chang, Dong-Hwan;Jung, Yun-Jae;Chun, Yeong-Han;Nam, Hae-Kon
    • Proceedings of the KIEE Conference
    • /
    • 2005.07a
    • /
    • pp.136-139
    • /
    • 2005
  • On-line dynamic security assessment is becoming more and more important for the stable operation of power systems as load level increases. The necessity is getting apparent under Electricity Market environments due to more various operating conditions. Fast transient stability analysis tool is required for contingency selection. The TEF(Transient Energy Function) method is a good candidate for this purpose. The clustering of critical generators is crucial for the precise and fast calculation of energy margin. In this paper, we propose a new method for fast decision of mode of instability by using stability indices. Case study shows very promising results.

  • PDF

A Study on Developing Voltage Stability Index arid System Stability by Incorporating Dynamic Load Modeling (부하모델을 고려한 전압 안정도 평가지표개발과 시스템 안정도 연구)

  • Wee, Won-Seok;Ham, Jung-Pil;Choo, Jin-Boo;Kim, Jung-Hoon
    • Proceedings of the KIEE Conference
    • /
    • 1999.11b
    • /
    • pp.187-189
    • /
    • 1999
  • Accurate load models allow more precise calculations of power system stability, This paper presents new static voltage stability index considering the load models. Also, We apply the load models for the existent voltage stability indices, and evaluate them.

  • PDF

An Empirical Study on Appraisal Indices' Discrimination Significance for Technology Financing: Focusing on KOTEC's Business Feasibility Appraisal Indices (기술금융 평가지표의 판별유의성에 관한 실증연구 : 기술보증기금의 기술사업성 평가지표를 중심으로)

  • Lee, Yong Hoon
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
    • /
    • v.15 no.5
    • /
    • pp.37-50
    • /
    • 2020
  • This study aims to investigate meaningful relationship between technology appraisal indices and SMEs' financial performances for their continuous growth. The empirical data for this study were based on the technology appraisal results of Korea Technology Finance Corporation(KOTEC) and the financial data of the following 2 years 0f 3,688 SMEs. The meaningful differences between SMEs with superb financial performances and the others, by using t-test analysis, statistically were verified in 25 indices(75.8%) out of total 33 indices. All of five independent variables, namely CEO's capability, technology manpower, R&D intensiveness, market competitiveness and investment feasibility, were verified to have a positive effect on business feasibility respectively and business feasibility also has a positive influence on financial performance, such as sales growth, labor productivity and financial stability.

Effects of EPS Assist Torque on On-center Steering Feel Indices (EPS 어시스트 토크에 의한 온 센터 조타감 성능지수 영향도 분석)

  • Kim, Sang Sup;Kyeong, Jin Sil
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.22 no.3
    • /
    • pp.186-193
    • /
    • 2014
  • On-center handling feel indices are the important numerical factors that meaning performance of manuability and stability felt by drivers. They should be considered to suspension design. The major factor that affect to these indices is the shape of assist torque curve. This paper presents the variables that meaning the shape of the assist torque curve and analyze the effect of each variables. And using interaction formulas, it is proposed that the method to extract the variables that satisfy the goal indices. The result of simulation that applied assist torque curve extracted by the method demonstrate the capability of this method with error under 8%.

Development of Predictive Models for Rights Issues Using Financial Analysis Indices and Decision Tree Technique (경영분석지표와 의사결정나무기법을 이용한 유상증자 예측모형 개발)

  • Kim, Myeong-Kyun;Cho, Yoonho
    • Journal of Intelligence and Information Systems
    • /
    • v.18 no.4
    • /
    • pp.59-77
    • /
    • 2012
  • This study focuses on predicting which firms will increase capital by issuing new stocks in the near future. Many stakeholders, including banks, credit rating agencies and investors, performs a variety of analyses for firms' growth, profitability, stability, activity, productivity, etc., and regularly report the firms' financial analysis indices. In the paper, we develop predictive models for rights issues using these financial analysis indices and data mining techniques. This study approaches to building the predictive models from the perspective of two different analyses. The first is the analysis period. We divide the analysis period into before and after the IMF financial crisis, and examine whether there is the difference between the two periods. The second is the prediction time. In order to predict when firms increase capital by issuing new stocks, the prediction time is categorized as one year, two years and three years later. Therefore Total six prediction models are developed and analyzed. In this paper, we employ the decision tree technique to build the prediction models for rights issues. The decision tree is the most widely used prediction method which builds decision trees to label or categorize cases into a set of known classes. In contrast to neural networks, logistic regression and SVM, decision tree techniques are well suited for high-dimensional applications and have strong explanation capabilities. There are well-known decision tree induction algorithms such as CHAID, CART, QUEST, C5.0, etc. Among them, we use C5.0 algorithm which is the most recently developed algorithm and yields performance better than other algorithms. We obtained data for the rights issue and financial analysis from TS2000 of Korea Listed Companies Association. A record of financial analysis data is consisted of 89 variables which include 9 growth indices, 30 profitability indices, 23 stability indices, 6 activity indices and 8 productivity indices. For the model building and test, we used 10,925 financial analysis data of total 658 listed firms. PASW Modeler 13 was used to build C5.0 decision trees for the six prediction models. Total 84 variables among financial analysis data are selected as the input variables of each model, and the rights issue status (issued or not issued) is defined as the output variable. To develop prediction models using C5.0 node (Node Options: Output type = Rule set, Use boosting = false, Cross-validate = false, Mode = Simple, Favor = Generality), we used 60% of data for model building and 40% of data for model test. The results of experimental analysis show that the prediction accuracies of data after the IMF financial crisis (59.04% to 60.43%) are about 10 percent higher than ones before IMF financial crisis (68.78% to 71.41%). These results indicate that since the IMF financial crisis, the reliability of financial analysis indices has increased and the firm intention of rights issue has been more obvious. The experiment results also show that the stability-related indices have a major impact on conducting rights issue in the case of short-term prediction. On the other hand, the long-term prediction of conducting rights issue is affected by financial analysis indices on profitability, stability, activity and productivity. All the prediction models include the industry code as one of significant variables. This means that companies in different types of industries show their different types of patterns for rights issue. We conclude that it is desirable for stakeholders to take into account stability-related indices and more various financial analysis indices for short-term prediction and long-term prediction, respectively. The current study has several limitations. First, we need to compare the differences in accuracy by using different data mining techniques such as neural networks, logistic regression and SVM. Second, we are required to develop and to evaluate new prediction models including variables which research in the theory of capital structure has mentioned about the relevance to rights issue.

Captive Model Test of Submerged Body Using CPMC (몰수체의 CPMC 구속모형시험)

  • Kim, Yeon-Gyu;Yun, Kun-Hang;Kim, Sun-Young;Kim, Dong-Jin
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.49 no.4
    • /
    • pp.296-303
    • /
    • 2012
  • The captive model test of submerged body using CPMC(Computerized Planar Motion Carriage) was carried out at the Ocean Basin of KORDI/MOERI. The target model is a submarine with general hullform. The forces and moments acting on the submerged body were measured by 6-axis waterproof gage. The oblique motion test and turning test were carried out in horizontal and vertical planes of the model. Maneuvering coefficients and derivatives were obtained from the test results. The stability indices in horizontal and vertical planes were obtained by using maneuvering derivatives. In this paper the introduction of test equipment and test results are presented.

A Voltage Stability Monitoring Algorithm using a Few PMUs in Metropolitan Area (한정된 위치의 PMU 정보를 이용한 수도권 전압안정도 감시 알고리즘)

  • Han, Sang-Wook;Lee, Byong-Jun
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.58 no.12
    • /
    • pp.2328-2334
    • /
    • 2009
  • Through the development of phasor measurement units (PMU), various aspects of power system dynamic behavior could be monitored and diagnosed. Monitoring dynamic voltage stability becomes one of achievements we can obtain from PMUs. It is very important to select the method appropriate to the KEPCO system since there are many voltage stability indices. In the paper, we propose an advanced WAVI (Wide Area Voltage Stability) for monitoring dynamic voltage stability. It reflects the PMU installation plan of KEPCO, thus it is suitable for KEPCO system specially. The salient features of the proposed index are; i) it uses only PMU measurements without coupling with EMS data. ii) it is computationally unburden so that it can be applied to real-time situation. The proposed index is applied to the KEPCO test system and the result shows that it successfully predicts voltage instability through the comparative studies.

Designing of the Beheshtabad water transmission tunnel based on the hybrid empirical method

  • Mohammad Rezaei;Hazhar Habibi
    • Structural Engineering and Mechanics
    • /
    • v.86 no.5
    • /
    • pp.621-633
    • /
    • 2023
  • Stability analysis and support system estimation of the Beheshtabad water transmission tunnel is investigated in this research. A combination approach based on the rock mass rating (RMR) and rock mass quality index (Q) is used for this purpose. In the first step, 40 datasets related to the petrological, structural, hydrological, physical, and mechanical properties of tunnel host rocks are measured in the field and laboratory. Then, RMR, Q, and height of influenced zone above the tunnel roof are computed and sorted into five general groups to analyze the tunnel stability and determine its support system. Accordingly, tunnel stand-up time, rock load, and required support system are estimated for five sorted rock groups. In addition, various empirical relations between RMR and Q i.e., linear, exponential, logarithmic, and power functions are developed using the analysis of variance (ANOVA). Based on the significance level (sig.), determination coefficient (R2) and Fisher-test (F) indices, power and logarithmic equations are proposed as the optimum relations between RMR and Q. To validate the proposed relations, their results are compared with the results of previous similar equations by using the variance account for (VAF), root mean square error (RMSE), mean absolute percentage error (MAPE) and mean absolute error (MAE) indices. Comparison results showed that the accuracy of proposed RMR-Q relations is better than the previous similar relations and their outputs are more consistent with actual data. Therefore, they can be practically utilized in designing the tunneling projects with an acceptable level of accuracy and reliability.