• Journal of Korea Foundry Society
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• v.18 no.4
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• pp.389-397
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• 1998

회주철 모재의 표면에 감압 플라즈마 용사법으로 실리콘 분말을 피복시킨 후 $CO_2$ 레이저를 이용하는 표면 합금화로 고온 내스케일성이 향상된 표면 개질층을 제조하였다. 실리콘의 표면 합금층에는 응집상의 흑연(chunky graphite)이 $Fe_5Si_3$로 구성된 망상의 화합물 기지속에 정출하는 조직특성을 보였다. 대기 분위기에서 18.0ks동안 열중량측정(TG)한 결과 실리콘 표면 합금층의 무게 증가율은 회주철 모재에 비하여 923K에서는 약 1/3, 1098K에서는 약 1/10을 나타내었다. 그리고 1098K에서 18.0ks동안 유지시킨 주철모재 시편에서 원래의 모재표면을 기준으로 다공성의 외부스케일과 편상흑연을 따라 생성된 내부스케일로 구성된 두께 $60{\sim}70\;{\mu}m$의 두꺼운 산화스케일이 생성되었으나, 실리콘의 표면 합금층에서는 두께 $3{\sim}5\;{\mu}m$의 치밀한 외부 산화스케일만이 생성되었다. 실리콘 합금층의 단면 미소경도값은 MHV $300{\sim}1100$으로 그 변동폭이 심하였으나, 진공분위기에서 열처리(1223K, 18.0ks)한 경우 미소경도값의 편차는 MHV $300{\sim}500$으로 개선되었다.

• Journal of Korean Society of Forest Science
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• v.86 no.3
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• pp.319-323
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• 1997

Perforated ray cells are identified for the first time in the Korean species of Deutzia glabrata, Deutzia sieboldiana, Hydrangea paniculata, and Philadelphus schrenckii that belong to Hydrangeaceae but not observed in Deutzia gracilis. These ray cells have simple to scalarifrom perforations in Deutzia glabrata which have vessel elements with scalariform perforations, and have scalariform to reticulate perforations in Deutzia sieboldiana, Hydrangea paniculata, and Philadelphus schrenckii which have vessel elements with scalariform perforations. Thus, the perforations of ray cells in Korean Hydrangeaceae appeared not to be exactly the same as the types of scalariform perforation plates in the vessel elements of same wood.

• The Korean Journal of Pharmacology
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• v.5 no.2
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• pp.105-114
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• 1969

The author studied the action of autonomic drugs on the urinary bladder isolated from Ditrema temmincki Bleaker and the results obtained were summarized as follows: 1) The motility of the urinary bladder of the fish was stimulated by acetylcholine and physostigmine. The stimulating action of these drugs was antagonized by atropine. 2) The motility of the fish bladder was stimulated by epinephrine, nor-epinephrine and phenylephrine, but inhibited by isoproterenol. 3) The inhibitory effects of isoproterenol on the fish bladder was not affected by phenoxybenzamine, but blocked by propranolol. 4) The excitatory effects of phenylephrine on the fish bladder were blocked by phenoxybenzamine, but augmented by propranolol. 5) The excitatory effects of epinephrine and nor-epinephrine were reversed by phenoxybenzamine and augmented by propranolol. 6) The motility of the fish bladder pretreated with phenoxybenzamine and propranolol was not affected by isoproterenol, phenylephrine, epinephrine and nor-epinephrine. 7) It seemed that the bladder muscle of the fish had both alpha excitatory and beta inhibitory receptors. 8) The motility of the fish bladder was stimulated by nicotine and DMPP. The excitatory effects of these drugs were abolished by pretreatment with hexamethonium or atropine. 9) It is, therefore, concluded that there are ganglion cells furnished with cholinergic fiber in the bladder wall of the fish.

• Korean Journal of Plant Taxonomy
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• v.41 no.2
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• pp.103-107
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• 2011

The seed characteristics of Withania somnifera were studied using light and scanning electron microscopy in order to determine the specific features of this species. The seed color is yellow, and the seed shape is reniform measuring between two to three millimeters. The seed of W. somnifera is exarillate and albuminous. The seed coat type is exotestal. The seed coat develops from a single integument. The young seed coat consists of single-layered exotesta, multi-layered mesotesta and single-layered endotesta. However, parenchymatous mesotesta layers are completely compressed at maturity. Therefore, the seed coat was represented by sclerenchymatous exotesta. The primary sculpture on the seed surface is reticulate, and cells are irregular in shape with undulating anticlinal walls. In addition, the seed surface has several characteristic holes between the anticlinal walls.

• The Transactions of the Korea Information Processing Society
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• v.4 no.5
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• pp.1319-1326
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• 1997

The Internet is a very convenient neteork, but not always a So.many orvanizations often require administrative security policies when they want to connect with ther organizations thtough a pubic network.A firewall is one way of protecting an internal network from the untrusted extemal network with a mechanism for selectively permiting or blocking traffic between the intermal network and the extermal network. The firewall also provides some limited Intemet access such as Ftp.Telet, etc.Usually , through a firewall system, X applications running on the extermal network may not access an X display on the intermal network.Thus, X applications run-ning on the extemal network are not supported through the usual firewall.In this paper, we propose a method of suppoting X application programs effedtively dffectvely through the firewall, overcoming this restriction.

• Journal of the Korea Safety Management & Science
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• v.12 no.3
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• pp.169-176
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• 2010

Owing to the latest changes in the IT environment and the advancement of RFID (Radio Frequency Identification) technology, the RFID technology has been frequently applied to the field of logistics and distribution. Now it is possible to acquire information in real-time more accurately and promptly as compared to data collection in the past, through the application of the RFID technology. However, in terms of the application of the RFID technology, the range of the field of logistics and distribution is considerably widely distributed. The management system that is able to monitor the RFID system installed in logistics centers and stores distributed in environmentally many regions, in real-time in the center is insufficient. Therefore, this study proposes a management system which is capable of transmitting the report of the occurrence of errors according to the pre-defined error types at the time of the occurrence of errors in the RFID system installed at each strategic foothold, in real-time to SMS and to the integrated monitoring system, and of taking actions for those errors from a remote place by using a mobile device. The purpose of the error management system proposed in this study is to minimize a data loss in the supplying network by quickly coping with errors in the area where the RFID system is installed.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1993.05a
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• pp.68-68
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• 1993

Immunohistochemistry combined with electron microscopy was employed to investigate the distribution of substance P -immunoreactive(SP-IR) nerve fibers in the tracheal submucosal gland of cats. SP-IR nerve fibers were found to form network around the glands. Numerous varicosities were also detected within the basement membrane of the acini and secretory tubules. All the intraglandular varicosities showed close spatial contact with serous cells, mucous cells and myoepithelial cells. Our findings suggest that SP-induced mucus secretion from tracheal submucosal glands in cats may be caused not only by glandular contractile response of myoepithelial cells but also by direct stimulation to both serous and mucous cells.

• Tuberculosis and Respiratory Diseases
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• v.45 no.5
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• pp.1098-1102
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• 1998

Sarcoidosis is a chronic multisystemic disorder of unknown cause characterized by presence of noncaseating epithelioid granuloma in affected organ. It is relatively common in western countries, but it is uncommon in East Asia including Korea. The lung is most frequently affected organ. Usual radiologic manifestation of thoracic sarcoidosis are readily recognized, but there are extremely diverse manifestation. Sarcoidosis rarely causes large pulmonary nodules, and cavitation in such lesion is very rare. We experienced one case of Sarcoidosis with Cavitary nodule of the lung and report it with brief review of the literature.

• Information and Communications Magazine
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• v.13 no.3
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• pp.61-70
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• 1996

In this paper, the architecture of the LAN Emulation service defined by the ATM Forum is introduced. In order to use the vast base of the existing LAN application software in ATM network. LAN Emulation provides a MAC layer service emulating connectionless services of legacy LANs on ATM networks. LAN Emulation forms a logical overlay network, called and emulated LAN, on top of an ATM network. LAN Emulation service comprises a set of LAN Emulation Clients(LECs) residing in end stations of an emulated LAN and three logical service entities : LAN Emulation Configuration Server (LECS), LAN Emulation Server(LES). and Broadcast and Unknown Server(BUS). LEC utilizes the services provided by these three servers to provide seamless interworking between legacy LANs and ATM networks, and to support transparent communications between LAN applications over ATM.

• Journal of Broadcast Engineering
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• v.13 no.1
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• pp.25-33
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• 2008

Video telephony is a representative service in 3G mobile network. And there have been efforts to improve quality of video telephony service in different fields. In Korea, the leading mobile service provider SKTelecom and KTF service the WCDMA network as 3G mobile network. Now, more than a million people is using the network. In this paper, we study about video telephony over WCDMA network. and propose error minimizing algorithm using cross-layer adaptation between physical layer and video codec. We simulated 3G-324M protocol with MPEG-4 video codec, and simulation results show suggested algorithm improve packet transmission rate for improving quality of video telephony service.