• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집A
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• pp.678-683
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• 2000

The one-dimensional performance model of a torque converter has been widely used to analyze and predict the performance and dynamic behavior of a torque converter. But this model doesn't include the information of the operating fluid properties. Therefore, to precisely predict dynamic performance of a torque converter, the effect of operating conditions must be considered through experimental coefficients such as friction loss coefficient and shock loss coefficient. And these coefficients cannot be achieved without experiments or internal flow analysis. In this study, the effects of varying material properties of operating fluid according to various operating temperatures are clarified with flow analysis of a torque converter. And these results are verified by comparing with those of performance experiment.

• 한국군사과학기술학회지
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• 제12권6호
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• pp.711-718
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• 2009

During the preliminary design phase of a supersonic aircraft, it is necessary to evaluate many potential engine/airframe combinations to determine the best solution to given set of mission requirements. And it is very important to establish a methodology to predict precisely afterbody drag so that accurate engine installed performance can be estimated. It was carried out in this paper to establish a methodology to predict afterbody drag of F-15K supersonic aircraft based on IMS(Integral Mean Slope) methodology, acquire afterbody drag data and compare its calculated data with the test data acquired from the wind tunnel test data based on 4.7% model scale. The comparison results showed good agreement between the calculated data and test data and it was found that the methodology described here to predict and test afterbody drag is acceptable.

• 한국태양에너지학회 논문집
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• 제30권4호
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• pp.86-91
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• 2010

The characteristics of hydrologic design parameters for small hydro power(SHP) sites located in four major river systems have been studied. The model, which can predict flow duration characteristic of stream, was developed to analyze the variation of inflow. And another model to predict hydrologic performance for SHP plants is established. The results from hydrologic performance analysis for SHP sites located on five major river systems based on the models developed in this study show that the specific design flowrate and specific output of SHP site have large difference between the river systems. The load factor, however, have small difference compared with specific design flowrate and specific output for all river systems. Also, it was found that the models developed in this study can be used to predict the primary design specifications of SSHP plants effectively.

• International Journal of Advanced Culture Technology
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• 제11권4호
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• pp.464-469
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• 2023

As modern society develops, the number of diseases caused by bad smells is increasing. As it can harm people's health, it is important to predict in advance the extent to which bad smells may occur, inform the public about this, and take preventive measures. In this paper, we propose a hybrid neural network structure of CNN and LSTM that can be used to detect or predict the occurrence of odors, which are most required in manufacturing or real life, using odor complex sensors. In addition, the proposed learning model uses a complex odor sensor to receive four types of data, including hydrogen sulfide, ammonia, benzene, and toluene, in real time, and applies this data to the inference model to detect and predict the odor state. The proposed model evaluated the prediction accuracy of the training model through performance indicators based on accuracy, and the evaluation results showed an average performance of more than 94%.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제16권11호
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• pp.1041-1045
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• 2010

클러스터는 병렬 컴퓨팅 및 데이터 센터에 적합한 구조를 제시하지만 설계 빛 확장을 할 때 성능에 대한 예측이 쉽지 않다 또한 기존의 클러스터 성능 분석은 이미 구성된 시스템만을 그 대상으로 한다는 문제점을 가지고 있으며 클러스터의 확장 및 대용량 클러스터에 대한 성능 예측을 지원하지 못한다. 그러므로 기존에 대규모 클러스터를 평가하던 방법들과는 다른, 시스템 구성 전 대규모 클러스터를 위한 모델링 및 예측 방법을 필요로 한다. 이러한 작업은 클러스터의 구조적 특성이 잘 반영되어야 하며 실제 시스템 적용 시 나타나는 문제에 관해서도 분석이 쉽게 되어야 한다. 본 논문에서는 대규모 클러스터의 성능 모델링을 위한 방법론을 제시하고 실제 시스템에서 수행한 측정 및 예측 결과로 방법론의 유용성을 보인다.

• Journal of Biosystems Engineering
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• 제37권3호
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• pp.131-139
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• 2012

In this study, we developed a simulation program for the prediction of tractive performance of a tractor, by applying a widely used empirical model for tractive performance prediction of single tire, Brixius. The tractive performance prediction program can readily predict and estimate tractive performance according to various soil conditions and different specifications of tractors. The program was developed with the considerations of tractor's specification-related parameters (e.g., weight, tire size, and wheelbase of the tractor), a soil parameter (i.e., cone index which represents the soil strength), and operating conditions of the tractor (e.g., theoretical speed and driving types such as 2WD and 4WD). Also, the program was designed to provide tractive performance prediction results of tractors such as gross traction, motion resistance, net traction, and tractive efficiency, in the form of not only numerical values but also graphical visualization. To evaluate the feasibility of the program, we input three different soil conditions (which have different cone indexes each other) and tractor operating conditions to the program and analyzed the tractive performance from each input condition. From the analysis, it can be concluded that the developed program can be effectively utilized to predict the tractive performance under various soil conditions and driving types of tractors with different specifications.

• 한국항공운항학회지
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• 제18권4호
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• pp.92-99
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• 2010

This study aimed to provide empirical evidence about expert performance approach in aviation field and the results suggested that the amount of experience(e.g. total flight hour) is necessary but not sufficient index of a pilot's expertise or superior performance. 43 pilots participated and completed a spatial span task and SA (situation awareness) tasks. To explore the factors predicting the performance in routine and non-routine situations, discriminant analysis was conducted. The results of discriminant analysis indicated that different variables are related with the performance in routine and non-routine situation. The factors predicting performance in routine situation were the spatial span scores and total flight hours. On the other hand, the factors predicting performance in non-routine situation were age and the qualification for instrument flying. In real world, total flight time which represents the quantity of experience has been frequently used to predict flight abilities and as an important index of expertise. The results of this study suggest that these kinds of factors have to be used cautiously to predict the performance in abnormal situation.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 1998년도 유체기계 연구개발 발표회 논문집
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• pp.49-54
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• 1998

The flow inside an axial turbomachinery with multi-stage can be characterized as unsteady phenomena. In order to predict accurately these complex unsteady flow patterns including rotor-stator interaction effects, enormous computer resources are required. So it is not compatible in preliminary design process. In this study, steady coupled blade row flow with rotor-stator interaction solver is developed using interrow mixing model and used to predict the performance of the axial fan. To verify the computational method, the calculations are compared with experimental results and show satisfactory agreement with them. The interaction effects on the performance of the axial fan have also been studied by comparing the results of steady coupled blade row and steady single blade row flow calculation.

• 설비공학논문집
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• 제22권6호
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• pp.353-360
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• 2010

Recently H1N1(swine flu) and SARS has been infected widely in the world; we have to care about germs and virus in indoor air environment. The air sterilization system investigated in this study allows occupants to turn on/off and to control the incoming air speed and direction. To predict the performance of air sterilization system without real experiment, a simulation is considered to compare and analyze the performance of the air sterilization systems in a typical office space. Multiple system parameters including volume flow rate and velocity of supply air were varied and investigated during the simulation. The investigation result shows that difference (between simulation and experiment) was about 3.5% in case of minimum air flow rate and about 0.2% in case of maximum air flow rate. The results indicate that multi-zone simulation technique can be used to predict the performance of a sterilization system in personalized office.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.1009-1012
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• 1999

An analytical performance model that can predict the performance of a superscalar processor employing multiple branch prediction is introduced. The model is based on the conditional independence probability and the basic block size of instructions, with the degree of multiple branch prediction, the fetch rate, and the window size of a superscalar architecture. Trace driven simulation is performed for the subset of SPEC integer benchmarks, and the measured IPCs are compared with the results derived from the model. As the result, our analytic model could predict the performance of the superscalar processor using multiple branch prediction within 6.6 percent on the average.