• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.8
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• pp.31-38
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• 1995

In this paper, we consider the leaky bucket parameter dimensioning problem in the presence of the cell delay variation(CDV) which arises at the customer premises network dud to the multiplexing with other traffic streams. We consider an ATM multiplexer in which a single CBR stream and several heterogeneous VBR traffic streams are multiplexed. Choosing an MMPP model for the bursty traffic streams, we derive an (MMPP+DD)/D/1/K queueing model for the evaluation of the CDV experienced by the CBR stream. We first evaluate the equilibrium queue length distribution embedded at tagged-cell arrival-time instants, based on whcih we calcuate the inter-cell time distribution and the distribution kof the number of tagged-cell departures in an arbitrary interval. Then we apply the analysis to the dimensionging problem of the leaky bucket parameters, examining how the employed traffic model affects the determination of the bucket size. Through numerical examples, we confirm that the Poisson traffic model can underestimate the bucket size, thus causing a considerable blocking probability for compliant use cells while the MMPP model can optimally design the bucket size which keeps the blocking probability under the target value.

• Communications of the Korean Mathematical Society
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• v.13 no.3
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• pp.603-627
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• 1998

The leaky bucket scheme is a promising method that regulates input traffics for preventive congestion control. In the ATM network, the input traffics are bursty and transmitted at high-speed. In order to get the low loss probability for bursty input traffics, it is known that the leaky bucket scheme with static leaky rate requires larger data buffer and token pool size. This causes the increase of the mean waiting time for an input traffic to pass the policing function, which would be inappropriate for real time traffics such as voice and video. We present the leaky bucket scheme with dynamic leaky rate in which the token generation period changes according to buffer occupancy. In the leaky bucket scheme with dynamic leaky rate, the cell loss probability and the mean waiting time are reduced in comparison with the leaky bucket scheme with static leaky rate. We analyze the performance of the proposed leaky bucket scheme in discrete-time case by assuming arrival process to be Markov-modulated Bernoulli process (MMBP).

• Journal of Acupuncture Research
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• v.26 no.1
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• pp.111-119
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• 2009

Objectives : The purpose of this study is to investigate the mechanism and effect of moxa bucket moxibustion, to be used as the quantitative data through the measurement of temperature, and to grasp the thermodynamic characteristics of moxa bucket moxibustion. Methods : We have selected the moxa bucket moxibustion. We have made a comparative study of the thermodynamic characteristics of moxa bucket moxibustion. We have examined combustion times, temperatures, temperature gradients in each period during a combustion of moxa bucket moxibustion made by oak wood. Results : 1. We could design the moxa bucket moxibustion so that it has $57.6^{\circ}C$ maximum temperature with 7g weight and 10mm height, if we use more weight of moxa or lower height of moxa, we can observe relatively elevated maximum temperature. We observed the maximum temperature following the measuring position of moxa bucket and we could see higher temperature at the center of the moxa bucket and lower temperature at the side of the moxa bucket. 2. We could design the moxa bucket moxibustion with 5g moxa and 10mm height so that it has 0.12 $1^{\circ}C/sec$ of maximum temperature gradient, and it has relatively high temperature gradient at lower weight and height condition. 3. We could design the moxa bucket moxibustion with 7g moxa and 15mm height so that it has 4,135sec of the longest effective temperature combustion time. If we use more weight of moxa or higher height of moxa, we can observe relatively extended effective temperature combustion time. Conclusions : We observed the longest effective combustion time following the measuring position of moxa bucket. We can see a higher temperature at the center of the moxa bucket and a lower temperature at the side of the moxa bucket.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.5
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• pp.1116-1125
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• 1997

In this paper, the modified UPC(Usage Parameter Control) algorithm is proposed. The proposed UPC algorithm is based on Leakey Bucket algorithm and adds the characteristics of the jumping window algorithm for monitoring the average bit rate. The proposed algorithm let a cell, which is tagged by Leaky Bucket algorithm, pass through the network, if the network does not violate the average bit rate. The measuring method of window mechanism like jumping window. This paper supposes On/Off traffic source model of rthe performance evaluation and analysis of the proposed algorithm. Therefore, as simulation results, the proposed algorithm acquires more reduced results of the cell loss rate and bucket size than the Leaky Bucket algorithm.

• Journal of Drive and Control
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• v.16 no.4
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• pp.9-15
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• 2019

Bucket trajectory is crucial regarding precision work with an excavator. In general, the bucket trajectory deviation is determined by the machining deviation of the frame, driving deviation of the driving hydraulic cylinder, clearance in the joints, and deformation of the structure. This paper investigated the relationship between the respective clearance in joints and the trajectory deviation of the bucket at the finishing work of the ditching for a 20-ton excavator. As a result, the larger the clearance, the larger deviation is increased at trajectory. However, it was found that the deviation of the rotation angle and displacement of the bucket was limited and the size of clearance does not affect closely on the contact angle of the pin shaft.

• The Journal of Engineering Research
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• v.6 no.2
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• pp.39-46
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• 2004

In this paper, we carry out a performance study related to the Broadband Network. For this network, it has been proposed to use the leaky bucket as a way of controlling congestion within the network. On the top of leaky bucket type rate based congestion control scheme for high speed networks, a user will typically operate an error control scheme for retransmitting lost and erroneous packets. We propose a performance model in order to study the interaction between a user's error control scheme and the leaky bucket congestion control scheme for high speed networks. Simulation results show that parameters such as the window size and the token generation rate in the leaky bucket are key factors affecting the end-to-end delay.

• Korean Journal of Remote Sensing
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• v.24 no.1
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• pp.17-24
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• 2008

Rainfall data from three different types of rain gauge system have been collected for the summertime rain event at Mokpo in the Korean peninsula. The rain gauge system considered in this paper is composed of three tipping-bucket rain gauges with 0.1, 0.2, and 0.5 mm measuring resolutions, the Optical Rain Gauge (ORG), and the PARSIVEL (PARticle SIze and VELocity). The PARSIVEL rainfall rate has been considered as the reference for comparison since it gave good resolution and performance on this event. Comparison with the PARSIVEL rainfall rate gives the results that the error and temporal variation of rainfall rate are simultaneously reduced with increasing the averaging interval of rainfall rate or decreasing the size of tipping bucket. This suggests that the estimated rainfall rate must be optimized, differently for the type of tipping-bucket rain gages, by minimizing the averaging interval of rainfall rate under the condition satisfying the given performance of rainfall rate.

• Journal of Animal Environmental Science
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• v.4 no.1
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• pp.21-28
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• 1998

This study was carried out to estimate the economic impacts on operation cost and curtail the bulking agent between two kinds of plants in swine farms. Bulking agents and Plants have a variety of roles in the fields of the composting for livestock manure and also represent an economic problem in terms of plant operation costs and compost production. Two farms which have rotary(size of reactor : 10${\times}$35${\times}$1.5m) or bucket(size of reactor : 10${\times}$68${\times}$2m) plants were used for 24 weeks for bucket conveyor system, which are composed of refilling rice hull as a bulking agent every 3 weeks till decreasing volume, for 4 weeks for rotary conveyor system, which has continuous compost production system without refilling rice hull, respectively. Composts was produced in 24 weeks in the bucket conveyor system, in 4 weeks in the rotary conveyor system, respectively. The results are as follows : 1. The tissue change of Rice hull at the composts of 45 days pursuant to composting steps was more crumbling in bucket conveyor system than in rotary conveyor system. 2. Microbial counts of the final composts for safety and quality showed that total bacteria counts was 1.01${\times}$108 cfu/g in bucket conveyor system, 2.82${\times}$108 cfu/g in rotary conveyor system, Salmonella was 0.3${\times}$102 cfu/g in bucket conveyor system, 7.6${\times}$102 cfu/g in rotary conveyor system, colifom bacteria was 0.5${\times}$106 cfu/g in bucket conveyor system, 1.5${\times}$106cfu/g in rotary conveyor system, fungi 1.24${\times}$106 cfu/g in bucket conveyor system, 0.01${\times}$106 cfu/g in rotary conveyor system, respectively. However, Any system used in this trial could not be met the regulation of A grade compost of EPA and USA. 3. C:N ratio according to the composting was more rapidly changed in bucket conveyor system with 64.5 of 5 days compost to 25.4 of final products than in rotary conveyor system with 26.7 of 5 days compost to 25.9 of final products. 4. Based on the mechanical characteristics of plants used in trial and compared with Rotary conveyor system, the Bucket conveyor system in which has 0.72 ㎥/㎥ of bulking agent capacity per slurry could be curtailed 1.78 ㎥of rice hull for disposal of waste, 1㎥. It was proper facilities to produce composts quantitative in Rotary conveyor system, and to treat waste quantitative and obtain good results in compost quality in Bucket conveyor system.

• Journal of the Korea Society of Computer and Information
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• v.3 no.1
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• pp.125-148
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• 1998

The use of shaping mechanism, realized by means of a leaky bucket based algorithm on input traffic of an ATM network allows to achieve higher utilization of network resources, and to guarantee the quality of service requested by the users. The functionalities of the shaping mechanism based on leaky bucket, are characterized by the token pool sire and by input queue size. In this paper we have analyzed, using simulations, the effect on the quality of service in ATM network of leaky bucket algorithm when shaper parameters described above are changed.

• Journal of Digital Contents Society
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• v.8 no.4
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• pp.573-579
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• 2007

The Leaky Bucket mechanism has been studied in many areas. There has been much interest in flow control in High Speed Networks using the Leaky Bucket. In this paper, We propose the Burst Tokens Fill method that performs well in Leaky Bucket to control the average rate, peak rate, and burst size. This scheme show the improvement of performance. However, This method does not apply all area of applications. Especially application of on-off shape is appropriate and the other area must need to care for appling this scheme.