• Journal of Biosystems Engineering
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• v.39 no.4
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• pp.377-388
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• 2014

Purpose: Determining the spatial structure of data is important in understanding within-field variability for site-specific crop management. An understanding of the spatial structures present in the data may help illuminate interrelationships that are important in subsequent explanatory analyses, especially when site variables are correlated or are a combined response to multiple causative factors. Methods: In this study, correlation, principal component analysis, and single and nested variogram models were applied to soil electrical conductivity and chemical property data of two fields in central Missouri, USA. Results: Some variables that were highly correlated, or were strongly expressed in the same principal component, exhibited similar spatial ranges when fitted with a single variogram model. However, single variogram results were dependent on the active lag distance used, with short distances (30 m) required to fit short-range variability. Longer active lag distances only revealed long-range spatial components. Nested models generally yielded a better fit than single models for sensor-based conductivity data, where multiple scales of spatial structure were apparent. Gaussian-spherical nested models fit well to the data at both short (30 m) and long (300 m) active lag distances, generally capturing both short-range and long-range spatial components. As soil conductivity relates strongly to profile texture, we hypothesize that the short-range components may relate to the scale of erosion processes, while the long-range components are indicative of the scale of landscape morphology. Conclusion: In this study, we investigated the effect of changing active lag distance on the calculation of the range parameter. Future work investigating scale effects on other variogram parameters, including nugget and sill variances, may lead to better model selection and interpretation. Once this is achieved, separation of nested spatial components by factorial kriging may help to better define the correlations existing between spatial datasets.

• Journal of Distribution Science
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• v.13 no.8
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• pp.73-80
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• 2015

Purpose - This study's objective is to analyze the content of the communications between users and producers based on the construal level theory. User generated content refers to content created in an online-based service where users and producers communicate interactively with each other. In a user generated content platform, the messages sent and received between the many players, the users and producers who use the content, may be analyzed at the psychological level based on construal level theory. Research design, data, and methodology - This study gathered user and producer participation through a snow-bowling sampling method. The data analyzed includes 125 video clips and 2,912 comments. The period of the data collection was from September 2014 to December 2014. The collected data was analyzed using a t-test and two-way ANOVA. Results - This study obtained the following research results. First, users who were a short social distance from producers responded to user participatory activities stated in concrete language rather than abstract language. In contrast, users who were at a longer social distance from producers tended to respond to the content requesting user participation through abstract language. Second, if users and producers were at a short social distance from each other, user preference increased more when a producer response to user participation was expressed concretely rather than when it was expressed abstractly. In contrast, if the users were at a longer social distance, users' preferences increased more when producer response was expressed abstractly rather than when it was expressed concretely. Conclusion - This study found that the effect of suitability, in which the social distance and the content were in congruence at the construal level, could be observed. Therefore, based on this, academic and practical implications were drawn. The three main insights of the study are as follows. First, firms can use psychological factors to analyze the message content of users in their distribution platforms. This study reveals managerial implications for marketing managers who want to take make use of this analysis of user and producer communications. This study indicates that the main factors include the concrete and abstract scores and social distance between users and producers. Second, we also provide the strategic guidelines to maximizing user preferences and other outcomes. The main dependent variable in this study is the user preference shift; the variable increases through the congruence effect; and the construal level is determined by the social distance between the users and producers and the type of producer response. The outcomes here from users can be utilized to develop several systemic strategies. One process to use the outcomes could be: (1) firms could measure the users and producers social distance; (2) calculate the concreteness or abstractness of the messages; and, (3) predict the user preference outcomes by the congruence between user and producer social distance and the abstractness or concreteness of the message content.

• The korean journal of orthodontics
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• v.45 no.4
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• pp.180-189
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• 2015

Objective: To compare the positions of the mandibular premolars in Angle Class I subjects according to vertical facial type. The results will provide a theoretical basis for predicting effective tooth movement in orthodontic treatment. Methods: Cephalometric parameters were determined using cone-beam computed tomography in 120 Angle Class I subjects. Subjects were categorized as short, normal, and long face types according to the Frankfort mandibular angle. Parameters indicating the position of the mandibular right premolars and the mandible were also measured. Results: The angle between the mandibular first premolar axis and buccal cortex, the distance between the root apex and buccal cortex, angle of vestibularization, arc of vestibularization, and root apex maximum movable distance were significantly greater in the short face type than in the long and norm face types. The angle between the mandibular second premolar axis and buccal cortex, the distance from root apex to buccal cortex, and the arc of vestibularization were significantly greater in the short face type than in the normal face type. Conclusions: There are significant differences in the mandibular premolar positions in Class I subjects according to vertical facial type.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.11
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• pp.1047-1053
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• 2011

In this paper, we proposed an HF-band wireless power transfer system with adaptive frequency control circuit for efficiency enhancement in a short range. In general, a wireless power transfer system shows an impedance mismatching due to a reflected impedance, because a coupling coefficient is varied with respect to separation distance between two resonating loop antennas. The proposed method can compensate this impedance mismatching by varying input frequency of a voltage-controlled oscillator adaptively with respect to separation distance. Therefore, transmission efficiency is enhanced in a short distance, where large impedance mismatch occurs. The adaptive frequency circuit consists of a directional coupler, a detector, and a loop filter. In order to demonstrate the performance of the proposed system, a wireless power transfer system with adaptive frequency control circuits is designed and implemented, which has a pair of loop antennas with a dimension of 30${\times}$30 $cm^2$. From measured results, the proposed system shows enhanced efficiency performance than the case without adaptive frequency control.

• PNF and Movement
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• v.17 no.2
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• pp.177-187
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• 2019

Purpose: The purpose of this study was to investigate the effects of combined training on the physical fitness of male short distance athletes. Methods: Combined training was applied with CLT and isokinetric training three times a week for eight weeks. For CLT, elastic bands were used in the sitting and standing positions to gradually increase sprint and skating movements. Isokinetic training was conducted at $60^{\circ}/sec$ and $180^{\circ}/sec$ to improve muscle strength and muscle power. Results: After the application of combined training, strength (hand force) improved from 42.25 kg to 47.30 kg. Muscle power for standing long jump improved from 240.00 cm to 248.80 cm, while the sergeant jump improved from 55.00 cm to 58.00 cm. Isokinetic testing showed that muscle strength ($60^{\circ}/sec$) improved from 315.65 %BW to 365.79 %BW for the left extensor and from 306.60 %BW to 325.00 %BW for the right extensor. The left flexor improved from 177.23 %BW to 189.47 %BW, but the right flexor decreased slightly from 210.87 %BW to 201.53 %BW. Muscle power ($180^{\circ}/sec$) improved from 254.00 %BW to 293.00 %BW for the left extensor and from 256.00 %BW to 272.00 %BW for the right extensor. The left flexor improved from 150.00 %BW to 162.00 %BW and the right flexor from 145.25 %BW to 182.00 %BW. Conclusion: Combined training could be used as a physical training program for male short distance athletes.

• Proceedings of the KIEE Conference
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• 2008.11a
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• pp.12-15
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• 2008

A distance relay has been widely used for transmission line protection. The distance relay detects a fault based on the calculated impedance i.e. the ratio of the voltage to the current measured from a current transformer (CT) and a coupling capacitor voltage transformer (CCVT), respectively. When a fault occurs and a CT saturates due to the magnitude of fault current, dc component, primary time constant, and the remanent flux of the iron core, the secondary current of a CT is distorted On the other hand, non-fundamental components generated during a fault can increase the error of a CCVT, particularly when a fault distance is short. The distortion of the current and voltage can cause mal-operation or the operating time delay of a distance relay. This paper describes the response of a distance relay considering the errors of a CT and a CCVT. The results indicate that the severe distortion of a CT and a CCVT have noticeable effect to a distance relay.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.2
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• pp.149-156
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• 2011

This paper reveals a distance estimation algorithm based on multi-code ultrasonic and wireless sensor network. For measuring the distances among the sensor nodes, each ultrasonic transmitter transmits multi-code ultrasonic signal simultaneously. Receivers use cross correlation method to separate the coded signals. The information of measured distances is broadcasted to each sensor node by wireless sensor network. The wireless sensor network measures the distance among the sensor nodes using the received signal strength of the broadcasting. The multi-code ultrasonic have a limitation of measurable distance. And the received signal strength is affected from an environment. This paper measures a distance using ultrasonic and a received signal strength in short range. These measured data are applied to the least square estimation algorithm. By the expansion of the fitting curve, a distance measurement in long range using the received signal strength is compensated. The coupled system reduce the error to an acceptable level.

• Journal of the Korean Society of Clothing and Textiles
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• v.18 no.1
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• pp.31-42
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• 1994

The purpose of this study was to investigate the effect of feeling distance of clothes in the person perception. The specific objectives were: 1) to investigate whether the compositions of clothes affect the rate of detouring, ; 2 ) to investigate whether the gender compositions of dyads affect the rate of detouring, ; 3) to investigate whether the distance between members of dyads affect the rate of detouring. ; 3) to investigate whether the distance between members of dyads affect the rate of detouring. ; 4) to investigate the .effect of the interaction among the compsitions of clothes, the gender compositions, and the distance between members of dyads in the person perception. For this study, two male and two female undergraduates were selected and wore business suit or casual wear as given by the researcher. The distance between members of dyads ranged from 100cm to 170cm with an increment unit of loom. The data from our observation were analysed by x2-test, ANOVA, and MCA. The major findings were ; 1) In male/male dyad, distance perception from clothes were affected by the compositions of clothes at all distance. In maleffemale dyad, when the distance between members of dyad is short, distance perception from clothes were affected by the compositions of clothes modes, 2) When two members of dyad wear business suit, distance perception from clothes were affected by the gender composions of dyads. 3) Distance perception from clothes were affected by distance factors at all the gender compositions of dyads. 4) In the person perception, the most imprtant clue was the distance between members of dyads. The pllysical distance, which was formed by clothes, was between 130cm and 140cm.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.11
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• pp.137-145
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• 2014

This paper suggests an LDA-based long distance face recognition algorithm for intelligent surveillance system. The existing face recognition algorithm using single distance face image as training images caused a problem that face recognition rate is decreased with increasing distance. The face recognition algorithm using face images by actual distance as training images showed good performance. However, this also causes user inconvenience as it requires the user to move one to five meters in person to acquire face images for initial user registration. In this paper, proposed method is used for training images by using single distance face image to automatically create face images by various distances. The test result showed that the proposed face recognition technique generated better performance by average 16.3% in short distance and 18.0% in long distance than the technique using the existing single distance face image as training. When it was compared with the technique that used face images by distance as training, the performance fell 4.3% on average at a close distance and remained the same at a long distance.

• Journal of the military operations research society of Korea
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• v.17 no.1
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• pp.105-129
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• 1991

Dynamic Time Warping(in short DTW) is a kind of sequence comparison method. It is widely used in human speech recognition. The timing difference between two speech patterns to be compared is removed by warping the time axes of the speech pattern by minimising the time-normalised distance between them. In the process of finding the minimum time-normalised distance. the efficient method is dynamic programming problem. This paper describes the concept of dynamic time warping method, mathematical formulation and an application.