• Journal of Plant Biotechnology
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• v.30 no.2
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• pp.155-160
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• 2003

Grapevine leafroll-associated virus 3(GLRaV-3) is one of the most severe pathogens for viral diseases found in Korea. This study was conducted to establish the virus-free stock production system for the virus disease control. The effects of thermotherapy, merestem culture and chemotheratpy to eliminate the GLRaV-3 in gratevines were tested. Thermotherapy at 37$\pm$2$^{\circ}C$ for 6∼8 weeks combined with 0.5∼1.0mm size of meristem culture method was the most effective for virus elimination. Thermotherapy alone was not effective. In chemotheratpy, DHT and Amantadine (20, 40mg/L) treatment in medium was more effective than Ribavirin to eliminate the GLRaV-3 in grapevine. However, Ribavirin spraying to potted was not available for virus elimination. Therefore, virus-free stock production system using the thermotherapy combined with shoot apical meristem culture was the most effective in grapevine.

• Journal of Korea Society of Digital Industry and Information Management
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• v.11 no.1
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• pp.89-96
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• 2015

The various services applied internet have been provided by the rapid development of wireless networks and providing multimedia contents are also increasing. It is caused a number of problems such as increasing of network traffic rapidly. P2P technique is gaining popularity for solving these problems. In particular, P2P technique in a wireless network environment has gained much popularity. Among them, MANET-based P2P techniques has been studied actively. It is not easy to be applied the existing technique as it is due to the dynamic topology and low bandwidth by moving nodes in MANET that is consisted of only mobile nodes. In this paper, we proposed sharing group construction technique for providing a stable connection between mobile nodes and reducing the load of network traffic and overhead of sharing group reconfiguration in order to improve data transmission performance between mobile nodes. The sharing group member nodes applied virtual sharing group generation technique with neighboring nodes of 1-hop distance in order to reduce traffic for file sharing. We performed comparative experiments with DHT technique to evaluate the performance of the proposed technique in this paper and the excellent performance is confirmed through experiments.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.3B
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• pp.517-525
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• 2010

The IPTV Service provides various interactive services beyond the level of being able to substitute cable TV. The IPTV system is to be decentralized gradually in which one server conducts all tasks. Primarily, deliberation of media needs to be changed into a system in which relayer and peer from the central server is utilized. Secondarily, the way of controling IPTV network need to be decentralized. Unlike the current client-server system, P2P(Peer To Peer), the main technology of decentralized IPTV is able to provide a service by cooperation of each node. Dealing with live streaming IPTV system which is based on the P2P protocol, this paper design the pure P2P IPTV structure and does verify the performance of P2P IPTV structure by realizing real system.

• The Korean Journal of Food And Nutrition
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• v.9 no.2
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• pp.181-188
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• 1996

Chemical compositions were investigated by harvested months and produced methods. The level of crude protein and crude ash of ginseng leaf tea harvested in July was slightly higher than it harvested in September. However, the level of crude fat and carbohydrate of ginseng leaf tea harvested in September were higher than it harvested in July. The results indicated that the harvest month influenced the chemical composition of the ginseng leaf tea. Also, the level of free sugar was increased when the ginseng leaf team harvested in September was produced by FHT(fermented and then hot-air dried) or HHT(heated and then hot-air dried). The results indicated that the subjects were preferred the color of ginseng leaf tea which was harvested in July. However, they were preferred the aroma and ginseng's aroma which was harvested and produced by HHT in September. Because they responded that the ginseng leaf tea tasted too bitter, it suggested that the taste of bitterness needed to remove. Also, the astringent, the savory, after aroma, and after say cry of the ginseng leaf tea was improved with FHT or HHT, and those results obtained from September's harvest rather than July's. Therefore, the overall quality of ginseng leaf tea which was harvested in September and produced with FHT or HHT were evaluated better than it of DHT(dried on the shade and then hot-air dried).

• Journal of Communications and Networks
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• v.8 no.3
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• pp.330-338
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• 2006

Many web cache systems and policies concerning them have been proposed. These studies, however, consider large objects less useful than small objects in terms of performance, and evict them as soon as possible. Even if this approach increases the hit rate, the byte hit rate decreases and the connections occurring over congested links to outside networks waste more bandwidth in obtaining large objects. This paper puts forth a client-cluster approach for improving the web cache system. The client-cluster is composed of the residual resources of clients and utilizes them as exclusive storage for large objects. This proposed system achieves not only a high hit rate but also a high byte hit rate, while reducing outgoing traffic. The distributed hash table (DHT) based peer-to-peer lookup protocol is utilized to manage the client-cluster. With the natural characteristics of this protocol, the proposed system with the client-cluster is self-organizing, fault-tolerant, well-balanced, and scalable. Additionally, the large objects are managed with an index based allocation method, which balances the loads of all clients well. The performance of the cache system is examined via a trace driven simulation and an effective enhancement of the proxy cache performance is demonstrated.

• Korean Journal of Artificial Intelligence
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• v.8 no.2
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• pp.1-5
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• 2020

Children's home accidents are less common than in the past. However, safety accidents continue to occur due to carelessness of the parents. To solve the problem, there are fall prevention screens that can withstand the weight of children, and safety railings that can be adjusted directly to solve the problem. However, these have disadvantages such as stability, convenience, and damage to the landscape. In this paper, we developed an automatic safety accident prevention fence system that can be installed on a window using Arduino, eliminating the disadvantages of previous safety accident prevention products. This system measures the height of a person standing in front of the fence and the distance between the person and the fence with two infrared sensors and moves automatically using a motor. In addition, in accordance with the U-Healthcare society, users can check the temperature, humidity, and fine dust concentration of the external environment through mobile. Each information can be obtained through DHT 11 sensor, fine dust concentration sensor, and Bluetooth connected toArduino. These can help the user's health care.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.3 no.1
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• pp.5-25
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• 2009

In recent years the popularity of multi-hop wireless networks has been growing. Its flexible topology and abundant routing path enables many types of applications. However, the lack of a centralized controller often makes it difficult to design a reliable service in multi-hop wireless networks. While packet routing has been the center of attention for decades, recent research focuses on data discovery such as file sharing in multi-hop wireless networks. Although there are many peer-to-peer lookup (P2P-lookup) schemes for wired networks, they have inherent limitations for multi-hop wireless networks. First, a wired P2P-lookup builds a search structure on the overlay network and disregards the underlying topology. Second, the performance guarantee often relies on specific topology models such as random graphs, which do not apply to multi-hop wireless networks. Past studies on wireless P2P-lookup either combined existing solutions with known routing algorithms or proposed tree-based routing, which is prone to traffic congestion. In this paper, we present two wireless P2P-lookup schemes that strictly build a topology-dependent structure. We first propose the Ring Interval Graph Search (RIGS) that constructs a DHT only through direct connections between the nodes. We then propose the ValleyWalk, a loosely-structured scheme that requires simple local hints for query routing. Packet-level simulations showed that RIGS can find the target with near-shortest search length and ValleyWalk can find the target with near-shortest search length when there is at least 5% object replication. We also provide an analytic bound on the search length of ValleyWalk.

• Horticultural Science & Technology
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• v.32 no.1
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• pp.26-32
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• 2014

We investigate the effect of post-conditioning periods and seed orientation on the vigor of cucurbit seeds with dry heat treatment (DHT). All the dry-heat treated seeds exhibited varying degree of seed vigor decreases. In general, pumpkin seeds showed less vigor decreases than the bottle gourd seeds. When the dry heat treated seeds were germinated after post-conditioning for 0, 30, and 120 days, the percentage of germination was enhanced by increasing the period of post-conditioning and the efficiency of post-conditioning differed by crop and cultivar. In both bottle gourd and pumpkin, the vigor of seeds placed in vertically upward and horizontal orientations was higher than that of the seeds placed in the vertically downward orientation. The results suggested that the vigor of dry-heat treated seeds could be improved by applying the proper post-conditioning and seed orientation.

• Korean Journal of Oriental Medicine
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• v.16 no.2
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• pp.131-141
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• 2010

Objective : Benign prostatic hyperplasia(BPH) is one of the most common diseased among elderly men. BPH can be treated with alpha-1 adrenergic blocker or $5{\alpha}$-reductase inhibitor(Finasteride) that reduces serum dihydrotestosterone(DHT). Phellodendri Cortex Ex has been broad studied on its chemical components, pharmacological activity, and clinical effects on anti-inflammation, anti-allergy, anti-tumor, immunity, antibacteria and other bioactivities. In this study, we investigated the therapeutic effects and action mechanism of Phellodendri Cortex Ex with a BPH induced by castration and testosterone treatment. Methods : Sprague-Dawley rats were treated with testosterone after castration for induction of experimental benign prostatic hyperplasia, which is similar to human benign prostatic hyperplasia in histopathological profiles. Phellodendri Cortex as an experimental specimen, and Finasteride as a positive control, were administered orally. The prostates were evaluated by histopathological changes, and the expression of $5{\alpha}$-reductase genes. Results : While prostates of control rats revealed severe acinar gland atrophy and stromal proliferation, the rats treated with Phellodendri Cortex Ex showed a diminished range of the tissue damage. In the reverse transcription-polymerase chain reaction(RT-PCR) of $5{\alpha}$-reductase genes, Phellodendri Cortex inhibited the expression of $5{\alpha}$-reductase genes. Conclusions : These findings suggest that Phellodendri Cortex Ex may protect the glandular epithelial cells and also inhibit stromal proliferation in association with the suppression of $5{\alpha}$-reductase. From these results, we suggest that Phellodendri Cortex Ex could be a useful agent for treating the benign prostatic hyperplasia.

• Journal of KIISE:Information Networking
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• v.34 no.2
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• pp.88-99
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• 2007

P2P systems are distributed data sharing systems, and each node in them plays the role of client as well as server. There are several studies using Distributed Hash Table, such as Chord, CAN, Tapestry, Pastry, but these systems don't consider the physical latency, therefore they have a weakness of difficulty to guarantee stable performance. To improve this problem, we present the TP2P system. This system is a self-organizing hierarchical overlay system and it uses Chord routing mechanism for lookup data. This system is organized by several subnets, each subnet is organized by physically close nodes, and global network organized by all nodes. In each subnet, one node finds a data, it saves in a node in the subnet, therefore it has higher probability to reduce physical lookup latency than Chord system. And each node has global information of some nodes in its subnet, and it is used to lookup data, therefore the number of hops decrease about 25% as well as the physical lookup latecy are reduced.