• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2004.05b
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• pp.475-478
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• 2004

In this paper, a CSSMA/AI MAC protocol for data services in packet CDMA network is presented. The proposed protocol is based on the code status sensing and reservation scheme. In the proposed protocol, the base station broadcast the rode status on a frame-by-frame basis just before the beginning of each preamble transmission, and the mobile station transmits a preamble for reserving a randomly selected code based on the received code status. After having transmitted the preamble, the mobile station listens to the downlink of the selected rode and waits for the base station reply. If this reply indicates that the code has been correctly acquired, it continues the packet transmission lot the rest of the frame. If there are other packets waiting for transmission, the base station broadcasts the status of the code as reserved, and the mobile station transmits a packet through the reserved code for the successive frames.

• Fire Science and Engineering
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• v.32 no.2
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• pp.24-29
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• 2018

To improve the fire safety of spring bed mattress, a cooling frame including cooling material (water) was made and a cooling frame was installed under the bed mattress or between the bed mattress and bed mattress base; fire tests (real scale) were conducted with or without a cooling frame. Similar fire behavior was observed at the beginning of the test (approximately 3 minutes). Subsequently, rapid fire growth in the mattress without a cooling frame, but with a cooling frame, the decline progressed without growth. The flame spread on the top surface of the bed mattress was similar in the semicircular direction, and the average flame speed velocity was analyzed at approximately 0.005 m/s. The maximum flame height was found to be approximately 2.7 m without a cooling frame, and approximately 1.8 m with a cooling frame installed. In addition, the maximum heat release rate was measured to be approximately 740 kW without a cooling frame, and approximately 400 kW with a cooling frame installed. As a result, the flame height and heat release rate were reduced when the bed mattress was fired through the installed cooling frame.

• The Transactions of the Korea Information Processing Society
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• v.6 no.1
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• pp.247-252
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• 1999

In order to realize a speech coding at low bit rates, a pitch information is useful parameter. In case of extracting an average pitch information form continuous speech, the several pitch errors appear in a frame which consonant and vowel are coexistent; in the boundary between adjoining frames and beginning or ending of a sentence. In this paper, I propose an Individual Pitch (IP) extraction method using residual signals of the FIR-STREAK digital filter in order to restrict the pitch extraction errors. This method is based on not averaging pitch intervals in order to accomodate the changes in each pitch interval. As a result, in case of Ip extraction method suing FIR-STREAK digital filter, I can't find the pitch errors in a frame which consonant and vowel are consistent; in the boundary between adjoining frames and beginning or ending of a sentence. This method has the capability of being applied to many fields, such as speech coding, speech analysis, speech synthesis and speech recognition.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.48 no.2
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• pp.11-23
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• 2011

In this paper, an accurate and fully automatic video object segmentation method is proposed for video conferencing systems in which the real-time performance is required. The proposed method consists of two steps: 1) accurate object extraction on the initial frame, 2) real-time object extraction from the next frame using the result of the first step. Object extraction on the initial frame starts with generating a cumulative edge map obtained from frame differences in the beginning. This is because we can estimate the initial shape of the foreground object from the cumulative motion. This estimated shape is used to assign the seeds for both object and background, which are needed for Graph-Cut segmentation. Once the foreground object is extracted by Graph-Cut segmentation, real-time object extraction is conducted using the extracted object and the double edge map obtained from the difference between two successive frames. Experimental results show that the proposed method is suitable for real-time processing even in VGA resolution videos contrary to previous methods, being a useful tool for immersive video conferencing systems.

• Journal of English Language & Literature
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• v.57 no.4
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• pp.625-649
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• 2011

Even though "An Outpost of Progress" and Heart of Darkness were based upon Joseph Conrad the sailor's same experience in Congo Free State, their narrative strategies are quite different. The realistic representation of "An Outpost of Progress," with which Conrad was not satisfied at all, was converted into the modernistic narrative strategy of Heart of Darkness so that the sympathetic power of the story should be improved. The conservative value system of realism is expressed by the omniscient author in "An Outpost of Progress," whereas the frame narrator of Heart of Darkness is proved to be an unreliable one whose norms and behavior are not in accordance with the implied author. The glorious history of the British Empire, which was proudly presented by the frame narrator at the beginning of Heart of Darkness, was strongly opposed by Marlow, another narrator, who said that the British Empire had been "one of the dark places of the earth" when ruled by the Roman Empire. The feeling of the frame narrator was uneasily changed into the gloomy mood when he described the Thames as the flow which "seemed to lead into the heart of an immense darkness" at the end of Heart of Darkness. Similar to the straightforward narrative strategy of representation in "An Outpost of Progress," the realistic approach of Part I in Heart of Darkness is considered by Conrad as insufficient to reveal the darkest truth of imperialism, which was declared by Kurtz as "The Horror! The Horror!" Thus Conrad uses the Chinese-box structure, in which Kurtz' episode is enveloped by Marlow's tale which is enclosed by the frame narrator's story, in order to penetrate into the mind of ordinary readers in the novelist's age of New Colonialism, while attacking the ideology itself of imperialism instead of critisizing its inefficiency and individualism.

• Journal of the Korean Home Economics Association
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• v.39 no.4
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• pp.1-18
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• 2001

Korea huts been dramatically changed during the last century in many aspect of society, with the introduction of western culture in the beginning of 20th century. This study aims at understanding the changes in our traditional culture shown by costume as well as examining the aspects of the changes of traditional clothing according to age, by comparing the differences of our traditional dress Hanbok between ear1y and the late of the 20th century. Analysis of photographs showing Hanbok of both ages was used. 155 photographs of people wearing traditional Hanbok in the beginning of the 20th century were collected from the photo collection books portraying various living conditions of common people at that time. 748 Photographs of Hanbok worm today were obtained by taking pictures of various occasions like wedding ceremonies in 5 big cities during 1997. The process of analysis consists of 3 stages: setting standards, sorting, and grouping by positioning. The results showed that traditional Hanbok room in the early 20th century has maintained its basic silhouette and design during the century, but the methods of color coordination, ornamentation, construction have underdone many changes in detail. Consequently, traditional frame exits, but actually there are many variations of tradition produced by individual tastes and fashion trend. These changes show that continuing influx of the western culture which has made enormous social changes in Korea had an influence even on Hanbok.

• The Plant Pathology Journal
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• v.15 no.6
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• pp.313-318
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• 1999

Cloning of the 5'untranslated region (5' UTR) and Nterminus of the glycoprotein precursor (G2G1) open reading frame of tomato spotted wilt virus has been problematic, possibly because of the toxicity of a signal peptide at the beginning of th G2G1 protein precursor. The toxicity of the signal peptide to bacterial growth and the reason for the expression of the peptide gene in Escherichia coli were investigated by cloning the 5' UTR and the signal peptide sequence separately. Cells transformed with the plasmid containing both the first 30 amino acids of the glycoprotein and the 5' UTR showed a severe growth inhibition whereas transformants harboring either the plasmid with the signal sequence or the 5'UTR alone did not show any ingibition. An E. coli promoter-like sequence was found in the 5'UTR and tis promoter acivity was confirmed with a promoter-less GUS gene cloned downstream of the 5'UTR. In the cloning of the Tomato spotted wilt virus (TSWV) glycoprotein G2G1 open reading frame all the recovered plasmids contained stop codons in the signal sequence region. However, clones containing no stop codon were recovered when the signal sequence and the 5'UTR were cloned separately.

• Earthquakes and Structures
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• v.4 no.3
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• pp.241-264
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• 2013

Since the beginning of the twentieth century, the progressive and rapid spread of reinforced concrete (RC) has led to the adoption of mixed masonry-RC solutions, such as the confined masonry. However, together with structures conceived with a definite role for earthquake behaviour, the spreading of RC technology has caused the birth of mixed solutions inspired more by functional aspects than by structural ones, such as: internal masonry walls replaced by RC frames, RC walls inserted to build staircases or raising made from RC frames. Usually, since these interventions rise from a spontaneous build-up, any capacity design or ductility concepts are neglected being designed only to bear vertical loads: thus, the vulnerability assessment of this class becomes crucial. To investigate the non-linear seismic response of these structures, suitable models and effective numerical tools are needed. Among the various modelling approaches proposed in the literature and codes, the authors focus their attention on the equivalent frame model. After a brief description of the adopted model and its numerical validation, the authors aim to point out some specific peculiarities of the seismic response of mixed masonry-RC structures and their repercussions on safety verification procedures (referring in particular way to the non-linear static ones). In particular, the results of non-linear static analyses performed parametrically to various configurations representative of different interventions are discussed.

• Journal of Welding and Joining
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• v.16 no.4
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• pp.92-97
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• 1998

Because of the low melting temperature of solder, each temperature cycle initiates an irrecoverable creep deformation at the solder interconnection which connects the package body with the PCB. The crack starts and propagates from the position where the creep deformation is maximized. This work has tried to compare and analyze the thermal fatigue life of solder interconnection which is affected by the lead material, the size of die pad, chip thickness, and interface delamination of 48-Pin TSOP under the temperature cycle ($0^{\circ}C$~1$25^{\circ}C$). The crack initiation position and thermal fatigue life which are calculated by using FEA method are well matched with the results of experiments. The thermal Fatigue life of copper lead frame is extended around 3.6 times longer than that of alloy 42 lead frame. It is maximized when the chip size is matched with the length of the lead. It tends to be extended as the thickness of chip got thinner. As the interfacial delamination between die pad and EMC is increased, the thermal fatigue life tends to decrease in the beginning of delamination, and increase after the delamination grew after 45% of the length of die pad.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.4
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• pp.68-78
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• 2003

Recently, low speed vehicle (LSV) is beginning to appear for various usages. The body of the LSV is usually made of the aluminum space frame (ASF) type rather than the monocoque or unitary construction type. A pa.1 of the reason is that it is easier to reduce mass efficiently while the required stiffness and strength are maintained. A design flow for LSV is proposed. Design specifications for structural performances of LSV do not exist yet. Therefore, they are defined through a comparative study with general passenger automobiles. An optimization problem is formulated by the defined specifications. At first, one pillar which has an important role in structural performances is selected and the reinforcements of the pillar are determined from topology optimization to maximize the stiffness. At second, the thicknesses of cross sections are determined to minimize the mass of the body while design specifications are satisfied. The optimum solution is compared with an existing design. The optimization process has been performed using a commercial optimization software system, GENESIS 7.0.