• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.41 no.1
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• pp.27-34
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• 2005

This study was conducted to examine the mesh selecivity and optimum mesh size of spring frame trap for conger eel. Conger myriaster. It was carried out on 25th Sep. 2002 at the coastal sea of Nung-po, Geojedo. The experimental fishing gear was used in five kinds of different mesh size spring frame trap that were 15mm, 20mm, 25mm, 30mm and 35mm, and one plastic pot as control fishing gear that was 6.7mm hole diameter. The mesh size 15mm, 20mm are the current gears, 25mm, 30mm are used in experiment, and 35mm is the legal mesh. These were made 50 traps, respectively. The mesh selectivity curve was analysed by the Kitahara's method(1968) and the optimum mesh size was estimated by relationship between the total length and diameter of conger eel and by the mesh selectivity master curve. The results obtained are summarized follows : 1. The total number of catch by the trap for conger eel was 835, it was consisted of 537 conger eel(64.4), 225 crabs(2639%) and 73 others(8.7%). 2. The value of maximum 1/m on the mesh selectivity curve was estimated at about 23.9. 3. The optimum mesh size of spring frame trap for conger eel was estimated 34.0mm in 50% selection range of the mesh selectivity master curve.

• Journal of Korea Society of Industrial Information Systems
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• v.19 no.1
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• pp.13-18
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• 2014

Sensor nodes are used for monitoring and collecting the environmental data via wireless sensor network. The wireless sensor network with various sensor nodes draws attention as a key technology in ubiquitous computing. Sensor nodes has very small memory capacity and limited power resource. Thus, it is essential to have energy efficient strategy for the sensor nodes. Since the sensor nodes are operating on the same frequency bands with ISM frequency bands, the interference by the devices operating on the ISM band degrades the quality of communication integrity. In this paper, the convolutional code is proposed instead of ARQ for the error control for the sensor network. The proposed convolutional code was implemented and the BER performance is measured. For the fixed transmitting powers of -19.2 dBm and -25dBm, the BER with various communication distances are measured. The packet loss rate and the retransmission rate are calculated from the measured BER. It is shown that the porposed method obtained about 9~12% and 12-19% reduction in retransmission rate for -19.2 dBm and -25 dBm respectively.

• Journal of Biosystems Engineering
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• v.43 no.1
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• pp.1-13
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• 2018

Purpose: The development of compact tractors that can be used in dry fields, greenhouses, and orchards for pest control, weeding, transportation, and harvesting is necessary. The development and performance evaluation of power transmission units are very important when it comes to tractor development. This study evaluates the performance of a driving power transmission unit of a 50 kW multi-purpose narrow tractor. Methods: The performance of the transmission and forward-reverse clutch, which are the main components of the driving power transmission unit of multi-purpose narrow tractors, was evaluated herein. The transmission performance was evaluated in terms of power transmission efficiency, noise, and axle load, while the forward-reverse clutch performance was evaluated in terms of durability. The transmission's power transmission efficiency accounts for the measurement of transmission losses, which occur in the transmission's gear, bearing, and oil seal. The motor's power was input in the transmission's input shaft. The rotational speed and torque were measured in the final output shaft. The noise was measured at each speed level after installing a microphone on the left, right, and upper sides. The axle load test was performed through a continuous equilibrium load test, in which a constant load was continuously applied. The forward-reverse clutch performance was calculated using the engine torque to axle torque ratio with the assembled engine and transmission. Results: The loss of power in the transmission efficiency test of the driving power unit was 6.0-9.7 kW based on all gear steps. This loss of horsepower was equal to 11-18% of the input power (52 kW). The transmission efficiency of the driving power unit was 81.5-89.0%. The noise of the driving power unit was 50-57 dB at 800 rpm, 70-77 dB at 1600 rpm, and 76-83 dB at 2400 rpm. The axle load test verified that the input torque and axle revolutions were constant. The results of the forward-reverse clutch performance test revealed that hydraulic pressure and torque changes were stably maintained when moving forward or backward, and its operation met the hydraulic design standards. Conclusions: When comprehensively examined, these research results were similar to the main driving power transmission systems from USA and Japan in terms of performance. Based on these results, tractor prototypes are expected to be created and supplied to farmhouses after going through sufficient in-situ adaptability tests.

• KIISE Transactions on Computing Practices
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• v.22 no.6
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• pp.284-289
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• 2016

In the Hadoop-based Big Data analysis model, the data movement between the legacy system and the analysis system is difficult to avoid. To overcome this problem, a unified Big Data file system is introduced so that a unified platform can support the legacy service as well as the analysis service. However, major challenges in avoiding the performance degradation problem due to the interference of two services remain. In order to solve this problem, we first performed a real-life simulation and observed resource utilization, workload characteristics and I/O balanced level. Based on this analysis, two solutions were proposed both for the system level and for the technical level. In the system level, we divide I/O path into the legacy I/O path and the analysis I/O path. In the technical level, we introduce an aggressive prefetch method for analysis service which requires the sequential read. Also, we introduce experimental results that shows the outstanding performance gain comparing the previous system.

• The Journal of the Korea Contents Association
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• v.16 no.9
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• pp.225-235
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• 2016

In this study, we analyze the community health survey data for 3 years from 2011 to 2013 were analyzed for evaluation. This study attempts to comprehensively evaluate differences between elderly medical aid beneficiaries and elderly health insurance beneficiaries in terms of health-related quality of life, All of elderly medical aid beneficiaries who responded community health survey were included for study and elderly health insurance beneficiaries were randomly selected as a control group by matching gender, age and location. The findings show that the elderly medical aid beneficiaries can not receive sufficient health care services, even though they have pay a low socio-economic status, spouse or fewer households enemies and poorer health behavior and higher morbidity of chronic diseases than the elderly health insurance beneficiaries do. But elderly health insurance beneficiaries also showed that not enough care utilization is high morbidity of chronic diseases. These factors aggravate the medical aid beneficiaries' health-related quality of life This characteristic was analyzed to lower health-related quality of life of the elderly. Therefore, it is necessary to strive for the development of appropriate services and programs taking into account the characteristics of the elderly that may go though a limited resource and promote the quality of life for the elderly more effectively re-evaluation of social services systems and programs related to elderly.

• The KIPS Transactions:PartD
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• v.12D no.3 s.99
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• pp.461-470
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• 2005

This paper suggests a new policy for consolidating a company's profits by segregating the clients using the contents service and allocating the media server's resources distinctively by clusters using the cluster analysis method of CRM, which is mainly applied to marketing. In this case, CRM refers to the strategy of consolidating a company's profits by efficiently managing the clients, providing them with a more effective, personalized service, and managing the resources more effectively. For the realization of a new service policy, this paper analyzes the level of contribution $vis-\acute{a}-vis$ the clients' service pattern (total number of visits to the homepage, service type, service usage period, total payment, average service period, service charge per homepage visit) and profits through the cluster analysis of clients' data applying the K-Means Method. Clients were grouped into 4 clusters according to the contribution level in terms of profits. Likewise, the CRFA (Client Request Filtering algorithm) was suggested per cluster to allocate media server resources. CRFA issues approval within the resource limit of the cluster where the client belongs. In addition, to evaluate the efficiency of CRFA within the Client/Server environment the acceptance rate per class was determined, and an evaluation experiment on network traffic was conducted before and after applying CRFA. The results of the experiments showed that the application of CRFA led to the decrease in network expenses and growth of the acceptance rate of clients belonging to the cluster as well as the significant increase in the profits of the company.

• The Transactions of the Korea Information Processing Society
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• v.3 no.2
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• pp.283-294
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• 1996

To operate the automatic devices of manufacturing process more effectively and to solve the needs of the resource sharing, network technology is applied to the unit control devices located in common manufacturing zone and operated by connecting them. This paper introduces deign and test operation of cell system for the management of multivendor PLC by applying to wall paper process based on the manufacturing standardization of CIM. The analysis of designed multivendor PLC group is performed by selecting the parameters such as variation of data packet size and node number of PLC ladder logic program and variation by analyzing the corresponding variation values of token rotation time and waiting time for the system operation. For the method of the analysis,the equation is considering the overhead such as indicated packet service time and transmission safety margin for PLC network connection in M/G/1 queue model,and it is applied to the cell system and PLC group manage-ment for operation .Through the experiment,it is found that the realtime processing is possible with expanded and better result than the resuit obtained by Jayasumana.Browaka with PLC scan time considered,response lower limit of 10-20 msec. data packet size not more than 50 bytes.and the number of nodes less than 40.

• Weed & Turfgrass Science
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• v.6 no.4
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• pp.322-332
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• 2017

Microbial fertilizer has been used to prompt turfgrass growth and quality and to prevent turfgrass diseases in turfgrass management of golf courses. This study was conducted to evaluate effects of microbial fertilizer containing Lactobacillus fermentum (MFcL) on changes of turfgrass quality and growth by investigating turf color index, chlorophyll index, clipping yield, and nutrient content in the turfgrass tissue. Treatments were designed as follows; non-fertilizer (NF), control fertilizer (CF), MFcL treatments [CF+$1.0g\;m^{-2}$(MFL), CF+$2.0g\;m^{-2}$ (2MFL)], and only MFcL treatment (OMF; $1.0g\;m^{-2}$ MFL). Chemical properties of soil by application of MFcL was unaffected. Turf color index, chlorophyll index, clipping yield and nutrient content and uptake of MFcL treatments were similar to CF. Furthermore, turfgrass shoot density of MFL was increased by 20% than that of CF, and that of OMF by 22% than NF. These results show that the application of microbial fertilizer containing L. fermentum increased turfgrass shoot density, which is not attributed to nutrient uptake in this study, but needs to be further investigated with other mechanisms such as biostimulant induction or phytohormone production.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.419-422
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• 2013

Conventional classifications of gastroenteropancreatic neuroendocrine tumours (GEP-NETs) are rather unsatisfactory because of the variation in survival within each subgroup. Molecular markers are being found able to predict patient outcome in more and more tumours. The aim of this study was to characterize the expression of the proteins cyclin D1, cyclin E and P53 in GEP-NETs and assess any prognostic impact. Tumor specimens from 68 patients with a complete follow-up were studied immunohistochemically for cyclin D1, cyclin E and P53 expression. High cyclin D1 and cyclin E immunostaining (${\geq}$ 5% positive nuclei) was found in 48 (71%) and 24 (35%) cases, and high P53 staining (${\geq}$ 10% positive nuclei) in 33 (49%). High expression of P53 was more common in gastric neuroendocrine tumors and related to malignant behavior, being associate with a worse prognosis on univariate analysis (RR=1.9, 95%CI=1.1-3.2). High expression of cyclin E was significantly associated with shorter survival in the univariate analysis (RR=2.0, 95%CI=1.2-3.6) and multivariate analysis (RR=2.1, 95%CI=1.1-4.0). We found no significant correlation between the expression of cyclin D1 and any clinicopathological variables. Our study indicated a prognostic relevance for cyclin E and P53 immunoreactivity. Cyclin E may be an independent prognostic factor from the 2010 WHO Classification which should be evaluated in further studies.

• Korean Journal of Environment and Ecology
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• v.33 no.6
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• pp.734-747
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• 2019

This study surveyed the visitors to the Seoseokdae Peak of the Mudeungsan National Park, to analyze the factors that affected user behavior, perception of the National Park, and satisfaction with the visit and establish the strategy for the management of the Mudeungsan National Park. The analysis result showed that Gwangju residents (78.1%) accounted for the majority of the visitors to the Seoseokdae Peak and that the Mudeungsan National Park showed the attributes of both mountain type and suburb type. Most visitors (91.2%) perceived that columnar joints, including the Seoseokdae Peak, possessed the largest resource value in the Mudeungsan National Park, and the visitors showed concern over the potential damage to vegetation in the Seoseokdae Peak as the result of the overcrowded visitors. Over half of the visitors showed a positive response to the measures like partially restricted access or detour of mountain path to preserve and restore the Seoseokdae Peak. The total visitors and the regional visitors (residents of Gwangju, Damyang, and Hwasun), indicated that the facility management aimed at facilitating visitor experience affected the most on the satisfaction with park management. Moreover, the regional visitors answered that the visit management to control disorder and overcrowding would increase satisfaction. The result of the importance-satisfaction analysis showed a difference between the total visitors and the regional visitors in needed improvements as the total visitors believed that "amenities and information facilities" should be improved while the regional visitors believed that the focus should be on the "prevention of illegal and disorderly behaviors" and the "amenities and information facilities."