• 한국항행학회논문지
• /
• 제24권2호
• /
• pp.128-133
• /
• 2020

본 연구에서는 위치추정을 하는 경우 선형회귀법을 반복적으로 적용하여 신호의 경로 손실을 추정하는 방법을 제안한다. 제안한 방식에서는 단말이 이동하면서 여러 위치에서 측정한 수신신호세기와 가속도계로 구한 측정 위치들 사이의 거리 정보를 이용하여 전송 비콘부터의 경로 손실을 선형회귀를 이용하여 추정한다. 전송 비콘과 특정 위치사이의 거리에 대하여 여러 잠정값들을 가정하고, 각 잠정값에 대하여 선형회귀식을 구한다. 이 선형회귀식들 중에서, 기준 수신 세기에 가장 가까운 식을 이용하여 송신 비콘와 목표 위치사이 거리를 구한다. 테스트 결과, 제안 방식은 단순 경로 손실 모델보다 훨씬 더 높은 정확도를 보인다.

• Journal of Ecology and Environment
• /
• 제30권2호
• /
• pp.201-207
• /
• 2007

Researchers have used a variety of methods to measure patterns of animal movement, including the use of spatial data (mapping the position of a moving animal at specified intervals) and direct estimation of travel path length by pacing under a moving animal or group. I collected movement data from five groups of siamangs (Symphalangus syndactylus) using two different methods concurrently to estimate the effects of the method of data collection on estimates of daily path length (DPL). Estimates of DPL produced from spatial data collected at 15-minute intervals were 12% lower than estimates of DPL produced by pacing under the traveling animal. The actual magnitude of the difference was correlated with the travel distance, but there was no correlation between the proportional difference and the travel distance. While the collection of spatial data is generally preferable, as spatial data permit additional analyses of patterns of movements in two or three dimensions, the relatively small difference between the DPL's produced using different methods suggests that pacing is an acceptable substitute where the collection of spatial data is impractical. I also subsampled the spatial data at increasing time intervals to assess the effect of sampling interval on the calculation of daily path lengths. Longer sampling intervals produced significantly shorter estimates of travel paths than shorter sampling intervals. These results suggest that spatial data should be collected at short time intervals wherever possible, and that sampling intervals should not exceed 30 minutes. Researchers should be cautious when comparing data generated using different methods.

• KIEAE Journal
• /
• 제5권1호
• /
• pp.35-42
• /
• 2005

The primary concerns of recreation plan are to provide visitors with quality of recreational experience and to protect of recreation resources. The quality of recreational experience is often defined in terms of social carrying capacity. The carrying capacity is revealed as perceived crowding. In this respects, measuring perceived crowding is useful tool of social carrying capacity determination. This study is to test the structural equation model that includes variables affecting perceived crowding. Through an on-site questionnaire survey, 467 visitors on Naejangsan national park were collected. The results of the study are follows. The encounter level on facility area is higher evaluated as crowding factor than other area in the park. It can be concluded that visitor perceived crowding when facility area situates high density use level rather than other areas expose high density use level. In the path analysis, the input variables(attitude, experience, encounter level) on the structural equation model affect significantly on perceived crowding. Especially, the attitude on the park management polocy is the most affecting factor on perceived crowding.

• 한국정밀공학회지
• /
• 제18권6호
• /
• pp.19-26
• /
• 2001

• 한국소음진동공학회논문집
• /
• 제19권8호
• /
• pp.773-780
• /
• 2009

The facility equipments generate dynamic force on building floor and the force can be measured with force transducer. However, this method depends on the measuring capacity or range of sensor, or mounts installation condition of equipments. Because of this restricting condition on force measuring system, this paper suggests a indirect method, the TPA(transfer path analysis) method, that produces a closely approximate dynamic force of equipments. This method calculates the dynamic force by using transfer response function. Firstly, the calculated dynamic force of impact load and continuous load was respectively compared with the sensor-measured value to examine the accuracy of TPA method. After that, the dynamic force and response induced by large facility equipments - a cooling tower, AHU and a large ventilator - were calculated by TPA method and the validity of these value were examined.

• 대한임베디드공학회논문지
• /
• 제9권6호
• /
• pp.323-334
• /
• 2014

In this paper, we proposed indoor positioning system with improved accuracy. The proposed indoor location measurement system is based pedestrian location measurement method that use the embedded sensor of smartphone. So, we do not need wireless external resources, such as GPS or WiFi signals. The conventional methods measure indoor location by generating a movement route of pedestrian by step and direction recognition. In this paper, to correct the direction sensor error, we use the common feature of the normal indoor floor map that the indoor path is lattice-structured. And we quantize moving directions depending on the direction of indoor path. In addition, we propose moving direction measuring method using geomagnetic sensor and gyro sensor to improve the accuracy. Also, the proposed step detection method uses angle and accelerometer sensors. The proposed step detection method is not affected by the posture of the smartphone. Direction errors caused by direction sensor error is corrected due to proposed moving direction measuring method. The proposed location error correction method corrects location error caused by step detection error without the need for external wireless signal resources.

• 전기학회논문지P
• /
• 제63권3호
• /
• pp.157-162
• /
• 2014

The active noise control(ANC) method for noise problems solution generally uses filtered-X LMS algorithms. However, Filtered-X LMS algorithms were mainly used but these had a limitation that had to measure a transfer function of secondary noise path. However, newly proposed correlation-LMS algorithms have slightly much calculation and are minutely behind performance, these have a advantage not in measuring transfer function onerously so that we can easily adapt these in real time. Thus Co-LMS algorithm was developed to improve the real-time implementation performance under the variable input noise such as road noise environment. In this paper, the performance of the Co-LMS is presented in comparison with that of the Filtered-X LMS algorithm. Simulation results show that active noise control using Co-LMS have slightly much calculation and are minutely behind performance, these have a advantage not in measuring transfer function onerously so that we can easily adapt these in real time.

• 대한간호학회지
• /
• 제28권3호
• /
• pp.550-562
• /
• 1998

The purpose of this study was to test the Theory of Planned Behavior in the prediction of contraceptive behavior among married women. This study used a descriptive correlational design to examine the relationships among the study variables. Eighty married women in Seoul and Kyungki-do participated in this study, Research instruments used were the tool for measuring TPB variables search as attitude toward contraception, subjective norm, perceived behavioral control, and intention ; and the tool for measuring contraceptive behavior. The former was modified by the researcher according to Ajzen & Fishbein(1980)'s guidelines for tool development and Jee (1993)'s tool. The latter was developed by the researcher Data was collected from July 20, 1996 to October 25, 1996. The results are as follows ; The three factors, attitude, subjective norm and perceived behavioral control of contraception can explain 30% of the variance in contraceptive intention. Inspection of path coefficient for each of the three predictor variables revealed that subjective norm and perceived behavioral control were the predictor variables on intention, while attitude was not. ; and intention and percevied behavioral control factors can explain 42% of the variance in contraceptive behavior. Inspection of path coefficient for each of the two predictor variables revealed that intention and perceived behavioral control were the predictor variables on behavior. In conclusion, this study identified that Theory of Planned Behavior was a useful model in the prediction of contraceptive behavior, and the contraceptive service program based on the TPB variables would be an effective nursing intervention for the change in contraceptive behavior.

• 경영과학
• /
• 제21권2호
• /
• pp.111-122
• /
• 2004

Measuring performance of corporate information system has become one of the core issues in that development of the information system requires substantial amount of investments and the system works as a crucial leverage to enhance competitive edge. Most of the previous researches for performance of the information system have narrow and limited focus on such as the effect of user satisfaction and productivity. This paper suggests a model to measures the comprehensive performance which is classified as user scope (user involvement and satisfaction), operational scope (task productivity, task innovation, customer satisfaction, management control) and efficiency scope (financial performance), and to represent the relationship among the scopes by the path analysis model. Followings are conclusions from statistical hypothesis test of the model: (i) user involvement through user satisfaction has positive effect on all the performances in the operational scope, (ii) task innovation and customer satisfaction in the operational scope has statistically significant impact on financial performance but task productivity and management control do not. This conclusion indicates that task productivity and management control has the long term effect in nature, and evaluation of the information system has managerial implication when it Is measured in comprehensive performance which includes internal operational performances as well as financial performance.

• International Journal of Precision Engineering and Manufacturing
• /
• 제5권1호
• /
• pp.60-68
• /
• 2004

The purpose of this paper is to establish an effective inspection system by using OMM (On-Machine Measurement) system based PC-NC. This system can reduce manufacturing lead time because a workpiece is inspected at every machining process and the manufacturing system which includes inspection faculty is able to realize on-line process on CNC machining center. The proposed OMM system is composed of a few algorithms for determination of inspection parameters. It is accomplished by determining the number of measuring points, their location, measuring path using fuzzy logic, Hammersley's method, TSP (Traveling Salesperson Problem) algorithm. The inspection feature applied to this system is based on machining feature. This method is tested by simulation and experiment that are analyzed measuring data and geometry tolerance.