• 제목/요약/키워드: Return Function

검색결과 390건 처리시간 0.03초

A Study on Path Planning Algorithm of a Mobile Robot for Obstacle Avoidance using Optimal Design Method

  • Tran, Anh-Kim;Suh, Jin-Ho;Kim, Kwang-Ju;Kim, Sang-Bong
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.168-173
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    • 2003
  • In this paper, we will present a deeper look on optimal design methods that are related to path-planning for a mobile robot. To control the motion of a mobile robot in a clustered environment, it's necessary to know a suitable trajectory assuming certain start and goal point. Up to now, there are many literatures that concern optimal path planning for an obstacle avoided mobile robot. Among those literatures, we have chosen 2 novel methods for our further analysis. The first approach [4] is based on HJB(Hamilton-Jacobi-Bellman) equation whose solution is the return-function that helps to generate a shortest path to the goal. The later [5] is called polynomial-path-planning approach, in this method, a shortest polynomial-shape path would become a solution if it was a collision-free path. The camera network plays the role as sensors to generate updated map which locates the static and dynamic objects in the space. Therefore, the exhibition of both path planning and dynamic obstacle avoidance by the updated map would be accomplished simultaneously. As we mentioned before, our research will include the motion control of a true mobile robot on those optimal planned paths which were generated by above algorithms. Base on the kinematic and dynamic simulation results, we can realize the affection of moving speed to the stable of motion on each generated path. Also, we can verify the time-optimal trajectory through velocity tuning. To simplify for our analysis, we assumed the obstacles are cylindrical circular objects with the same size.

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고객 요구사항을 반영한 아파트 개발 사업 기획 모델 (A Planning Model for Apartment Development Project Reflecting Client Requirements)

  • 김유신;오예근;김재준
    • 한국건설관리학회논문집
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    • 제5권3호
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    • pp.88-96
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    • 2004
  • 고객 요구사항은 기업의 여러 성과와 관련하여 최근 이에 대한 관심이 증가되고 있는 개념이며, 특히 국내 건설업에서 큰 비중을 차지하는 아파트 사업의 경우 다각도의 조사를 통해 고객의 요구사항을 발굴하고 이를 사업에 반영하여 품질을 향상시키는 노력이 필요하다. 이를 위해서는 고객의 요구사항을 파악하고 아파트 사업에 적용하는 기법이 요구되며 QFD(Quality Function Deployment)와 연계된 ROQ(Return On Qualify)는 제조업에서 사용되는 기법으로 고객의 요구사항을 조사하여 고객만족을 향상시키고 이를 품질개선 프로그램에 적용해 수익성을 향상시키게 하는 프로세스이다. 본 연구에서는 ROQ 프로세스의 적용을 통해 아파트 품질관리 개선방안을 제시하였다. 이를 위해 먼저 소비자 면접조사와 FGI(포커스그룹 인터뷰) 조사 실시 및 고객의 요구사항을 분석하였으며, 그 후 전문가의 면담을 통해 새로운 아파트 상품 개발에 적용 가능한 품질개선 프로그램을 수립하였다. 이 프로세스를 통해 새로운 아파트 품질관리 개선방안을 제시하도록 한다.

금융 지표와 파라미터 최적화를 통한 로보어드바이저 전략 도출 사례 (A Case of Establishing Robo-advisor Strategy through Parameter Optimization)

  • 강민철;임규건
    • 한국IT서비스학회지
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    • 제19권2호
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    • pp.109-124
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    • 2020
  • Facing the 4th Industrial Revolution era, researches on artificial intelligence have become active and attempts have been made to apply machine learning in various fields. In the field of finance, Robo Advisor service, which analyze the market, make investment decisions and allocate assets instead of people, are rapidly expanding. The stock price prediction using the machine learning that has been carried out to date is mainly based on the prediction of the market index such as KOSPI, and utilizes technical data that is fundamental index or price derivative index using financial statement. However, most researches have proceeded without any explicit verification of the prediction rate of the learning data. In this study, we conducted an experiment to determine the degree of market prediction ability of basic indicators, technical indicators, and system risk indicators (AR) used in stock price prediction. First, we set the core parameters for each financial indicator and define the objective function reflecting the return and volatility. Then, an experiment was performed to extract the sample from the distribution of each parameter by the Markov chain Monte Carlo (MCMC) method and to find the optimum value to maximize the objective function. Since Robo Advisor is a commodity that trades financial instruments such as stocks and funds, it can not be utilized only by forecasting the market index. The sample for this experiment is data of 17 years of 1,500 stocks that have been listed in Korea for more than 5 years after listing. As a result of the experiment, it was possible to establish a meaningful trading strategy that exceeds the market return. This study can be utilized as a basis for the development of Robo Advisor products in that it includes a large proportion of listed stocks in Korea, rather than an experiment on a single index, and verifies market predictability of various financial indicators.

다변량 판별분석과 로지스틱 회귀모형을 이용한 민간병원의 도산예측 함수와 영향요인 (Discriminant Prediction Function and Its Affecting Factors of Private Hospital Closure by Using Multivariate Discriminant Analysis and Logistic Regression Models)

  • 정용모;이용철
    • 보건행정학회지
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    • 제20권3호
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    • pp.123-137
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    • 2010
  • The main purpose of this article is for deriving functions related to the prediction of the closure of the hospitals, and finding out how the discriminant functions affect the closure of the hospitals. Empirical data were collected from 3 years financial statements of 41 private hospitals closed down from 2000 till 2006 and 62 private hospitals in business till now. As a result, the functions related to the prediction of the closure of the private hospital are 4 indices: Return on Assets, Operating Margin, Normal Profit Total Assets, Interest expenses to Total borrowings and bonds payable. From these discriminant functions predicting the closure, I found that the profitability indices - Return on Assets, Operating Margin, Normal Profit Total Assets - are the significant affecting factors. The discriminant functions predicting the closure of the group of the hospitals, 3 years before the closure were Normal Profit to Gross Revenues, Total borrowings and bonds payable to total assets, Total Assets Turnover, Total borrowings and bonds payable to Revenues, Interest expenses to Total borrowings and bonds payable and among them Normal Profit to Gross Revenues, Total borrowings and bonds payable to total assets, Total Assets Turnover, Total borrowings and bonds payable to Revenues are the significant affecting factors. However 2 years before the closure, the discriminant functions predicting the closure of the hospital were Interest expenses to Total borrowings and bonds payable and it was the significant affecting factor. And, one year before the closure, the discriminant functions predicting the closure were Total Assets Turnover, Fixed Assets Turnover, Growth Rate of Total Assets, Growth Rate of Revenues, Interest expenses to Revenues, Interest expenses to Total borrowings and bonds payable. Among them, Total Assets Turnover, Growth Rate of Revenues, Interest expenses to Revenues were the significant affecting factors.

Intervention Strategy Applied ICF Checklists for Sitting Cross-Legged in Patient with Multiple Ligament Knee Injury: Single Subject Study

  • Kim, Chan Yang;Kwon, Jung-Won
    • The Journal of Korean Physical Therapy
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    • 제33권3호
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    • pp.168-177
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    • 2021
  • Purpose: This study applies the ICF to identify the patient's body function, structure, and participation, evaluates the patient's environmental factors and individual factors, and is a high level of movement to return to the society of patients with multiple ligament injury of the knee joint. Methods: Progressive strength training and ROM exercise were performed 30 minutes a day, 5 times a week for 6 weeks. The evaluation was performed by examining the ROM, length, MMT, instability, dynamic balance, pain and depression. Results: The ROM of the knee joint was improved from 110° to 135° after intervention, and the knee flexion length decreased from 69 cm to 45 cm. Knee flexor is Good after intervention from Poor-, and knee extensor is Good+ after intervention from Poor, and the plantar flexor of the ankle joint improved from Poor- before intervention to Good after intervention and dorsi-flexor of the ankle joint improve to Good from Poor. Pain index was moderate before and after the intervention, with a score of 3, 2 after the intervention, and when maintaining the sitting cross-legged, the before intervention score was 7 to 4 after the intervention. Conclusion: The patient's posture of sitting cross-legged was maintained from 30 seconds before intervention to 14 minutes after intervention. These results were able to set the hypothesis design, intervention method and goal that the multifaceted approach of environment and individual factors as well as body function and structure area, activity and participation area using ICF checklists, it is helped the patient to return to daily life.

Design of a UWB Antenna with Band-Notch Function

  • Fanli, Zeng;Lee, Jae-Won;Kim, Chul-Hee;Choi, Jae-Hoon
    • Journal of electromagnetic engineering and science
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    • 제10권1호
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    • pp.39-44
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    • 2010
  • In this paper, a compact wideband antenna with a band-notch function is proposed. It operates over the UWB band with a band-stop characteristic. To increase the impedance bandwidth, a ring-shaped radiator is used. By attaching a circular stub to the ring-shaped radiator, the band-notch performance is obtained. The proposed antenna operates over a frequency range from 2.7 GHz to 11 GHz to satisfy the 10-dB return-loss requirement and provides band-stop performance in the frequency band from 5.15 GHz to 6.1 GHz. Experimental results reveal that the proposed antenna exhibits good radiation performance and is suitable for UWB applications.

산지사면의 실측토양수분을 이용한 전이함수 모형의 적용 (Transfer Functional Modeling Using Soil Moisture Measurements at a Steep Forest Hillslope)

  • 김상현
    • 한국환경과학회지
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    • 제22권4호
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    • pp.415-424
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    • 2013
  • In this paper, time series of soil moisture were measured for a steep forest hillslope to model and understand distinct hydrological behaviours along two different transects. The transfer function analysis was presented to characterize temporal response patterns of soil moisture for rainfall events. The rainfall is a main driver of soil moisture variation, and its stochastic characteristic was properly treated prior to the transfer function delineation between rainfall and soil moisture measurements. Using field measurements for two transects during the rainy season in 2007 obtained from the Bumrunsa hillslope located in the Sulmachun watershed, a systematic transfer functional modeling was performed to configure the relationships between rainfall and soil moisture responses. The analysis indicated the spatial variation pattern of hillslope hydrological processes, which can be explained by the relative contribution of vertical, lateral and return flows and the impact of transect topography.

St. Thomas Hospital 심정지액에 Creatine Phosphate 를 첨가한 후 심근 보호 효과 (Enhanced Myocardial Protection by Addition of Creatine Phosphate to the St. Thomas Hospital Cardioplegic Solution -Studies in the rat -)

  • 최순호
    • Journal of Chest Surgery
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    • 제22권4호
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    • pp.580-588
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    • 1989
  • The potential for enhancing myocardial protection by adding high-energy phosphate to cardioplegic solutions [St. Thomas Hospital solution] was investigated in a rat heart model of cardiopulmonary bypass and ischemic arrest. Creatine phosphate was evaluated as an additive to the St. Thomas Hospital cardioplegic solution. Creatine phosphate 10.0 mmol/L as the optimal concentration which improved recovery of aortic flow and cardiac output after a 30 minute period of normothermic [37oC] ischemic arrest. In comparing mechanical function in both groups the mean postischemic recoveries of aortic flow, cardiac output, stroke volume and stroke work [expressed as a percentage of its preischemic control] were significantly greater in STH-CP group than in CP- free control group. In addition to improving function and decreasing CK release, CP reduced reperfusion arrhythmias significantly decreasing the time between cross-clamp removal and return to regular rhythm from 81.8 * 13.9 [sec] in CP-free group to 35.9 * 6.8 [sec] in CP group [P< 0.05] so, exogenous CP exerts potent protective and antiarrhythmic effects when added to the St. Thomas Hospital cardioplegic solution. However, the mechanism of action remains to be elucidated.

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Maximal United Utility Degree Model for Fund Distributing in Higher School

  • Zhang, Xingfang;Meng, Guangwu
    • Industrial Engineering and Management Systems
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    • 제12권1호
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    • pp.36-40
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    • 2013
  • The paper discusses the problem of how to allocate the fund to a large number of individuals in a higher school so as to bring a higher utility return based on the theory of uncertain set. Suppose that experts can assign each invested individual a corresponding nondecreasing membership function on a close interval I according to its actual level and developmental foreground. The membership degree at the fund $x{\in}I$ is called utility degree from fund x, and product (minimum) of utility degrees of distributed funds for all invested individuals is called united utility degree from the fund. Based on the above concepts, we present an uncertain optimization model, called Maximal United Utility Degree (or Maximal Membership Degree) model for fund distribution. Furthermore, we use nondecreasing polygonal functions defined on close intervals to structure a mathematical maximal united utility degree model. Finally, we design a genetic algorithm to solve these models.

A Study on the Automatic Diagnosis of ECG

  • Jeong, Gu-Young;Yu, Kee-Ho;Kwon, Tae-Kyu;Lee, Seong-Cheol
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.55.4-55
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    • 2001
  • Analyzing the ECG signal, we can find heart disease. Myocardial ischemia is a disorder of cardiac function caused by insufficient blood flow to the muscle tissue of the heart. Myocardial ischemia is inscribed on ST-segment of the ECG during and after patient takes exercise or is under stress, but after long time past, the ECG pattern is return to steady state. Therefore, it is necessary to monitor and analyze the ECG signal continuously for patient or aged people. Our primary purpose is the detection of temporary change of the ST-segment of ECG automatically. In the signal processing, the wavelet transform decomposes the ECG signal into high and low frequency components using wavelet function. Recomposing the high frequency bands including QRS complex, we can detect QRS complex more easily ...

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