• Journal of Korea Water Resources Association
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• v.41 no.1
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• pp.27-34
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• 2008

Groundwater development in coastal areas induces saltwater intrusion. In many cases amount of groundwater resources available for development is limited by a pre-specified limit of additional saltwater intrusion. In this paper a simple equation is developed to assess available groundwater resources which depends on the constraint of acceptable additional saltwater intrusion. Strack#s single-potential analytical solution is used to derive the equation. Available groundwater increases as more additional intrusion is allowed. However, critical points limit both the maximum pumping rate and the allowed saltwater intrusion limit. The equation is presented in the form of design curves from which the maximum pumping rate can be read off quickly. The equation and the design curves are suitable for preliminary estimation of available groundwater resources in coastal areas.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.9A
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• pp.1359-1371
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• 1999

In this paper, we propose an efficient explicit rate (ER) feedback switch algorithm for available bit rate (ABR) flow control. In order to improve the disadvantages of existing ER feedback switch algorithms with congestion avoidance, the proposed scheme adjusts the target utilization dynamically according to the queue length and its growth rate. also, we investigate the performance of the proposed switch algorithm and compare it with ERICA and NIST switches using simulation. Simulation results show that the proposed switch algorithm can control the cell emission rate of a source rapidly according to variations of available link bandwidth by using dynamic adaptation of target utilization. It also exhibits a better performance than the existing ER feedback switches in terms of queue length and link utilization.

• Journal of Pharmaceutical Investigation
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• v.17 no.3
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• pp.135-139
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• 1987

This study was attempted to investigate the dissolution rate and the bioavailability of commercially available sulfamethoxazole and trimethoprim (SMX-TM) tablets in rabbits. The dissolution test was conducted in artificial gastric juice by basket method with eight SMX-TM tablets which were chemically equivalent. According to the dissolution rate, SMX-TM tablets were divided into four groups, such as rapid, intermediate, slow and very slow groups for the bioavailability test in rabbits. The results were as follows: 1) The dissolution rate of brand A was most rapid but brand H was most slow in artificial gastric juice. 2) Area under the blood concentration curve was larger in the order of brand A > C > E > H in rabbits. 3) There was a little difference in pharmacokinetic parameters such as biological half life, absorption rate constant and $t_{max}$. 4) The relationship between the dissolution rate and relative bioavailability was significant in brand A, C, E and H. From the results of this experiment, the bioavailability of SMX-TM tablets in rabbits may be predicted from the results of dissolution rate studies.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1338-1341
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• 1997

In this paper, we propose angular rate computation algorithm using GPS carrier phase. A direct angylar rate masurement has not previously been available form GRS, although its availability is highly desirable for use in state feedback control. So we propose angular rate computationalgorithm which derive angular rate from the velocity of differentiated carrier phase og GPS. The proposed algorithm contains attitude determination using double-differentiated carrier phase and 2 baseline configuration whcih provide more practical applications than 3 baseline.

• International Journal of Internet, Broadcasting and Communication
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• v.12 no.4
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• pp.166-172
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• 2020

Video streaming application such as YouTube is one of the most popular mobile applications. To adjust the quality of video for available network bandwidth, a streaming server provides multiple representations of video of which bit rate has different bandwidth requirements. A streaming client utilizes an adaptive bit rate scheme to select a proper video representation that the network can support. The download behavior of video streaming client player is governed by several parameters such as maximum buffer size. Especially, the size of the maximum playback buffer in the client player can greatly affect the user experience. To tackle this problem, in this paper, we propose the maximum buffer size optimization according to available network bandwidth and buffer status. Our simulation study shows that our proposed buffer size optimization scheme successfully mitigates playback stalls while preserving the similar quality of streaming video compared to existing ABR schemes.

• Journal of Plant Biology
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• v.10 no.1_2
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• pp.21-30
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• 1967

The aim of present study is to elucidate the relationship between decay rate of soil organic matter, and the change of soil microbial population under the oak and pine forest soils in Kwang-nung plantation stand. The results obtained are as follows: 1) The correlation coefficient between decay rate and the soil bacteria is 0.84 and fungi 0.93. 2) The distribution of soil microbial population is higher in both F horizon of the oak forest soil, and F and H horizon of the pine forest soil. However, the number of soil microorganisms decreases with the depth in each forest soil. 3) The population of soil microbes is related to moisture content, total nitrogen, available phosphorus, and exchangeable calcium, except organic carbon in fungi. 4) The soil organic matter has been mainly decomposed by fungi, and the size of its population are governed by the factors such as moisture content, organic carbon, total nitrogen, available phosphorus, and exchangeable calcium.

• Journal of Dental Anesthesia and Pain Medicine
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• v.22 no.2
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• pp.129-143
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• 2022

Background: Patient-controlled analgesia (PCA) has been widely used as an effective medical treatment for pain and for postoperative analgesia. However, improper dose errors in intravenous (IV) administration of narcotic analgesics from a PCA infusion pump can cause patient harm. Furthermore, opioid overdose is considered one of the highest risk factors for patients receiving pain medications. Therefore, accurate delivery of opioid analgesics is a critical function of PCA infusion pumps. Methods: We designed a microbalance method that consisted of a closed acrylic chamber containing a layer and an oil layer with an electronic balance. A commercially available infusion analyzer (IDA-5, Fluke Co., Everett, WA, USA) was used to measure the accuracy of the infusion flow rate from a commercially available smart PCA infusion pump (PS-1000, UNIMEDICS, Co., Ltd., Seoul, Korea) and compared with the results of the microbalance method. We evaluated the uncertainty of the flow rate measurement using the ISO guide (GUM:1995 part3). The battery life, delay time of the occlusion alarm, and bolus function of the PCA pump were also tested. Results: The microbalance method was good in the short-term 2 h measurement, and IDA-5 was good in the long-term 24 h measurement. The two measurement systems can complement each other in the case of the measurement time. Regarding battery performance, PS-1000 lasted approximately 5 days in a 1 ml/hr flow rate condition without recharging the battery. The occlusion pressure alarm delays of PS-1000 satisfied the conventional alarm threshold of occlusion pressure (300-800 mmHg). Average accuracy bolus volume was measured as 63%, 95%, and 98.5% with 0.1 ml, 1 ml, and 2 ml bolus volume presets, respectively. A 1 ml/hr flow rate measurement was evaluated as 2.08% of expanded uncertainty, with a 95% confidence level. Conclusion: PS-1000 showed a flow accuracy to be within the infusion pump standard, which is ± 5% of flow accuracy. Occlusion alarm of PS-1000 was quickly transmitted, resulting in better safety for patients receiving IV infusion of opioids. PS-1000 is sufficient for a portable smart PCA infusion pump.

• The korean journal of orthodontics
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• v.24 no.3 s.46
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• pp.535-546
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• 1994

The research work has been conducted in order to establish facts on posterior available space in patients with crowding. The relation between crowding and posterior available space was worked out through a cross sectinal study of fifty eight patients showing class I malocclusion. In addition, a longitudinal overlapping study was done by examing twenty patients who had their bicuspid extracted and forty nine patients who did not, at the orthodontic department of dental clinic affiliated in Chosun University. The patients had been examined for three years and eight months on a regular basis, and the study yielded the following conculusion. 1. There was a great difference in posterior available space between patients with serious crowding and those with slight crowding. The former marked 15.2mm of posterior available space and the latter 19.9mm. 2. Posterior crowding index was acquired by joint consideration of the diameter of posterior teeth and posterior available space, and manifested the highest relationship with crowding among measured items. 3. Patients who had their bicuspids extracted exhibited increase in posterior available space of 1.6mm/year and those who did not 1.8mm/year. 4. The absorption of anterior border of ramus turned out to be most deeply related with the increase of posterior available space. 5. Anterior border of ramus was absorbed at the average rate of 0.7mm/year during the period of observation. 6. The extraction of bicuspids had little influnce on the change in posterior available space.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.5
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• pp.1384-1396
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• 1998

This paper ivestigates the performance of a relative rate (RR) switch algorithm for the rate-based available bit rate (ABR) flow control in asynchronous transfer mode (ATM) networks. A RR switch may notify the network congestion status to the source by suing the congestion indication (CI) bit or no increase (NI)bit in the backward RM (BRM) cells. A RR switch can be differently implemented according to the congestion detectio and notification methods. In this paper, we propose three implementation schemes for the RR switch with different congestion detection and notification methods, and analyze the allowed cell rate (ACR) of a source and the queue length of a switch in steady state. In addition, we derive the upper and lower bounds for the maximum and minimum queue lengths for each scheme respectively, and evaluate the effects of the ABR parameter values on the queue length. Furthermore, we suggest the range of the rage increase factor (RIF) and rate decrease factor (RDF) parameter values which can prevent buffer overflow and underflow at a switch.

• Journal of Internet Computing and Services
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• v.8 no.5
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• pp.125-132
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• 2007

Transmission mechanisms that include an available bandwidth estimation algorithm and a packet loss differentiation scheme, in general, exhibit higher TCP performance in wireless networks. TCP New Jersey, known as the best existing scheme in terms of goodput, improves wireless TCP performance using the available bandwidth estimation at the sender and the congestion warning at intermediate routers. Although TCP New Jersey achieves 17% and 85% improvements in goodput over TCP Westwood and TCP Reno, respectively, we further improve TCP New Jersey by exploring improved available bandwidth estimation, retransmission timeout, and recovery mechanisms. Hence, we propose TCP New Jersey PLUS (shortly TCP NJ+), showing that under 1% packet loss rate, it outperforms 3% by TCP New Jersey and 5% by TCP Wes1wood. In 5% packet loss rate, a characteristic of high bit-error-rate wireless network, it outperforms other TCP variants by 19% to 104% in terms of goodput even when the network is in bi-directional congestion.