• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.273-276
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• 2000

Marine fungus, Thraustochytrium aureum ATCC 34034, was incubated in artificial sea water media in order to produce docosahexaenoic acid(DHA). Cultures were performed at $24^{\circ}C$ in light for 13 days with orbital shaker at 100rpm. Maximum cell productivity of 1.34g/L and DHA yield of 41.4 mg/L were obtained by using this method, which is almost the twice level of DHA yield obtained for the strains reported previously. This strain did produce much more DHA after sporangium disruption.

• Bulletin of the Korean Chemical Society
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• v.11 no.3
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• pp.221-224
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• 1990

A kinetic study of the heterobimetallic dimer disruption of $PPN+^aCrMn(CO)_{10}$- by ligand L(L = CO, $PR_3$) is described. The rate was determined in several aprotic solvents. The results indicated that the reaction of $PPN+^aCrMn(CO)_{10}$- with $PR_3$ is of first order with respect to [$PPN+^aCrMn(CO)_{10}$-] and the heterolytic Cr-Mn bond dissociation energy is approximately 27 kcal/mol.

• Journal of Korea Multimedia Society
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• v.11 no.10
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• pp.1446-1459
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• 2008

In an infrastructure-based wireless network, an access point is used for all communications among mobile devices. However, when a mobile device moves into a dead Bone, a connectivity disruption between the mobile device and the access point occurs. Such connectivity disruption consequently leads to another connectivity disruption between the mobile device moving toward the dead zone and other wireless-enabled devices located within the area of the infrastructure-based wireless network. To cope with the connectivity disruption in the infrastructure-based wireless network the ad hoc network that dynamically forms a network without any preexisting communication infrastructure needs to be set up to provide seamless connections among mobile devices. In this paper, we propose the DNSQ-MAC (Dynamic Network State aware QoS-Medium Access Control) technique that meets the deadlines of MAC frames forwarded over hop-by-hop multipaths and guarantees the QoS performance of an ad hoc-based wireless network. Mobile devices incorporating the DNSQ-MAC technique are capable of adjusting to the new dynamic network status in order to enhance the QoS performance in the ad hoc-based wireless network. A case study which exploits the Qualnet simulator shows that the proposed DNSQ-MAC technique can guarantee the deadlines of MAC frames forwarded over hop-by-hop multipaths and enhance the QoS performance of various routing protocols and packet schedulers running on the network layer above the MAC layer.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37A no.10
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• pp.850-857
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• 2012

A moving network is the usage model that provides the mobile stations to the communication service via the mobile relay deployed in the high-speed vehicle. The mobile relay periodically performs the signal strength measurement of the neighbor base stations to select the target base station during the handover procedure. The mobile stations experience the service disruption during the measurement of the mobile relay. In this paper, we propose the estimation based scanning method to overcome the service disruption of the mobile stations connected via the mobile relay. In the proposed method, mobile stations subordinated in the mobile relay periodically measure the signal strength of neighbor base stations in order to perform handover. The measured signal strength is used to estimate the signal strength between the mobile relay and the neighbor base station. We performed simulations in order to evaluate the performance of the proposed method in terms of the estimation accuracy and the overhead due to the exchange of channel information. By the simulation result, The estimation error is less than 4dBm when more than 6 mobile stations are used for the estimation. The overhead caused by the proposed method is less than that caused by the direct measurement of the mobile relay when the data rate is more than 8Mbps.

• Journal of Microbiology and Biotechnology
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• v.16 no.1
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• pp.109-117
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• 2006

The Rev binding to Rev Responsive Element (RRE) of HIV-1 mRNA plays an important role in the HIV-I viral replication cycle. The disruption of the Rev-RRE interaction has been studied extensively in order to develop a potential antiviral drug. In order to provide the basis for a more promising approach to develop a Rev-RRE binding inhibitor against HIV-I infection, it is necessary to understand the binding modes of the aminoglycoside antibiotics to RRE. In the present study, the binding mode of a modified antibiotic, a neamine conjugated with pyrene and arginine (NCPA), to RRE has been studied by the methods of $T_m$ measurement and spectroscopic analysis of RRE with or without antibiotics. The results confirmed that NCPA competes with Rev in binding to RRE.

• Journal of English Language & Literature
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• v.55 no.6
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• pp.1123-1137
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• 2009

Revisiting the horror of slave mutiny in nineteenth century America via Julia Kristeva's concept of abject, this essay examines abject fear in Amasa Delano and Babo's subversive act to deceive Delano in Herman Melville's "Benito Cereno." Babo, the slave, exercises subversive power, thereby reversing racial hierarchy aboard the slave ship-the San Dominick. Babo's ability to mimic and control racial stereotypes exposes how nineteenth-century racial hierarchy was only a social fiction, which becomes the very source of Delano's fear. Delano's dread belies upon the possible disruption of social order triggered by Babo'sblack rebellion. In order to repress his fear, Delano consciously and unconsciously attempts to re-inscribe white dominion and reaffirm black inferiority and stereotypes by means of rationalizing the disturbing signs he witnesses on the San Dominick. When Delano discovers the realsituation of the ship, he must relinquish the abject resonance that disturbs the previous racial order. Employing a legal document, Delano re-inscribes the official position of the blacks as slaves, defining them as violent savages, and thereby silences Babo. However, Melville's text is not a testament to white power. "Benito Cereno" actually endorses abject instability to challenge racial hierarchies through the poignant image of Babo's dead gaze in the last scene of the novella. Thus, "Benito Cereno" exemplifies the recurring power of abject as a threat to social hierarchy and as a constant reminder of the falsity and insecurity of a social order.

• Korean Journal of Adult Nursing
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• v.13 no.3
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• pp.409-419
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• 2001

The reference study was performed to investigate the nursing importance which was based a theoretical background related to horticultural therapy and to examine the possibility which horticultural therapy was applicable as a nursing intervention through analysis on a preceding study. The research subjects related to the areas of horticultural therapy which related as a nursing intervention, were psychological, physical, environmental, and psycho-social aspects. It is judged that the horticultural therapy is effective in treating depression, emotional disruption or anxiety. It seems to be also effective in increasing the muscular tension and, thereby, expanding the scope of joint movements. Such theories show that horticultural therapy may be a good alternative nursing means. Plants act to create a pleasant interior atmosphere by generating anion, controlling the temperature and humidity and purifying the air, and therefore, the horticultural therapy may be applied to clinic or environmental therapy. When horticultural therapy is used as a nursing intervention, patients' sociopsychological needs may be fulfilled. It has been found that horticultural therapy is instrumental in treating perceptive or emotional disruption, depression, loss of self-respect, disrupted everyday activities and social behaviors. In particular, horticultural therapy seems to be effective in managing chronic patients' crisis or improving life quality. Intervention method applied on a preceding study was activity therapy and scene therapy in the horticultural therapy The above findings suggest that the pro-environmental horticultural therapy is useful as a new paradigm of nursing or holistic nursing conducive to improvement of health. So, it is desirable to prove its effects by applying it in the clinic. In order to apply horticultural therapy as a nursing intervention, it will be necessary to educate nurses on principles and methods of horticultural therapy and encourage them to apply it in nursing and clinics. Moreover, it may well be necessary to develop landscape therapy as nursing intervention as well as a variety of horticultural therapy programs befitting the clinic conditions. On the other hand, we need to provide for some scientific ground for horticultural therapy through continued studies. In this regard, this study which focuses on patients' health improvement through change of environment. may well provide for a framework for such studies.

• Journal of KIISE:Information Networking
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• v.34 no.4
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• pp.287-295
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• 2007

IETF's FMIPv6 protocol enables a mobile node to switch to the reactive mode of handover operation when the prediction of the movement is incorrect. In this case, the mobile node may experience severe service disruption due to large handover latency and packet loss. In order to solve this problem, we propose a fast mobile IP handover with multiple pre-registrations. In the proposed approach, the new temporary IP addresses are prepared in advance at multiple locations where the mobile node may probably move into. In this case, even though the prediction is wrong, the mobile node can move into the alternative locations without causing service disruption. We have designed and implemented a prototype system, and measured the performance of the proposed system. The experimental results show that the proposed approach can reduce the handover latency drastically.

• BMB Reports
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• v.35 no.3
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• pp.291-296
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• 2002

Thanatin, a 21-residue peptide, is an inducible insect peptide with a broad range of activity against bacteria and fungi. It has a C-terminal disulfide loop, like the frog skin secretion antimicrobial peptides of the brevinin family. In this study, we tried to find the effect of a number of amino acids between the disulfide bond. Thanatin showed stronger antibacterial activity to Gram negative bacteria than other mutants, except Th1; whereas, the mutant peptides with deletion had higher activity to Gram positive bacteria than thanatin. An increase in the number of amino acid(s) using the alanine residue decreased the antibacterial activity in all of the bacteria. Th1 with deletion of threonine at position 15 ($Thr^{15}$) showed similar antibacterial activity against Gram-negative bacteria, but had higher activity against the Gram positive bacteria. In order to study the structure-function relationship, we measured liposome disruption by the peptides and CD spectra of the peptides. Th1 also showed the highest liposome leaking activity and α-helical propensity in the sodium dodecyl sulfate solution, compared with other peptides. Liposome disruption activity was closely correlated with the anti-Gram positive bacterial activity. All of the peptides showed no hemolytic activity. Th1 was considered to be useful as an antimicrobial peptide with broad spectrum without toxicity.

• Journal of KIISE:Information Networking
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• v.31 no.2
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• pp.146-157
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• 2004

In order to provide continuous QoS guaranteed to a mobile user, it is required to deploy some kind of mechanisms which reserves resources in advance at the locations to which the mobile user is expected to move. An important issue with regards to these mechanisms is to minimize the waste of resources caused by redundant reservations while keeping up the QoS guaranteed services to the user In this paper, we propose a wireless network domain structure which deploys a special cell, called “a gray cell”. The boundaries of two or more neighboring domains are surrounded by the gray cells, and the gray cells are supposed to belong to all of its neighboring domains. Based on this wireless domain structure, we propose a mechanism which completely removes the waste of redundant resource reservation in the wireless network domain while greatly reducing the risk of reservation disruption caused by inter-domain handover. Using simulation, it is shown that the proposed mechanism can deal with inter-domain handover as effectively as it does with intra-domain handover. It is also presented that the proposed mechanism outperforms existing mechanisms with respect to reservation disruption time and packet losses caused by handovers.