• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.5
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• pp.47-56
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• 1999

Tensile energy absorption in paper has long been measured as the area under the load-elongation curve. Little effort has been made to define where and how that energy is used within the paper itself. Characterization of tensile energy absorption in paper is discussed. Multiple small elements within newsprint and kraft sack have been defined and the energy absorbed in those elements are discussed. The tensile profiles of the weak paper, newsprint, and the tough paper, kraft sack, are presented as separate strain profiles, stress profiles, and strain energy density profiles. This allows a complete analysis of the energy absorption of both papers for comparison or contrast.

• Review of KIISC
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• v.1 no.2
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• pp.63-75
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• 1991

창간호에 이어 본고에서는 공개 키 암호시스템(public key dryptosystem)중 Merkle- sack 방법과 RSA공개 키 암호시스템 그리고 McEoiece 공개키 암호 시스템에 대한 자세한 분석을 기술하고자 한다.

• Journal of KIISE:Information Networking
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• v.27 no.2
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• pp.160-174
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• 2000

Nowadays, most widely used transport protocol, TCP is tuned to perform well in traditional networks where packet losses occur mostly because of congestion. TCP performs reliable end-to-end packet transmission under the assumption of low packet error rate. However, networks with wireless links suffer from significant losses due to high error rate and handoffs. TCP responds to all losses by invoking congestion control and avoidance algorithms, resulting in inefficient use of network bandwidth and degraded end-to-end performance in that system. To solve this problem, several methods have been proposed. In this paper, we analyse and compare these methods and propose appropriate model for improving TCP performance in the network with wireless links. This model uses TCP selective acknowledgement (SACK) option between TCP ends, and also uses caching method at the base station. Our simulation results show that using TCP SACK option with base station caching significantly reduces unnecessary duplicate retransmissions and recover packet losses effectively.

• Journal of IKEEE
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• v.12 no.1
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• pp.8-17
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• 2008

Recently, GMAHN that provides interface between MANET and Wired Network has been focused in mobile communication. It is necessary that the technology provide reliable data transmission technology between mobile node and wired network in MANET environment that is varied by the node movement. In this paper, using the TCP protocol(Tahoe, Reno, Vegas, SACK)that increases reliability between source and destination, we applied the TCP protocol mechanism to various environment, and proposed the most efficient TCP mechanism by comparing each mechanism.

• Journal of the Korean Institute of Landscape Architecture
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• v.20 no.3
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• pp.21-32
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• 1992

This paper is studied on the concept of environmental cognition on accordance with the oriental(especially Buddhism) process of thinking. The Yeongiron(theroy : one of th most famous philosophy of Buddhism, the theory of cause and occasion) consists of the upgam-yeongi, the aroeyasik-yeongi, the chinyeo-yeongi and the pupkye-yeongi. And the concept of these theory are as follows: The conceptural elements of upgam-yeongi consist of sack(色), soo(受), sand(想), hand(行), sik(識). The elements connects with the western environmental psychology such as sack and objects, soo and stimuli, sand and perception, hand and cognition, sik and behavior. Similarly, aroeyasik-yeongi that consist of sangbun(相分), kyunbun(見分), chajungbun(自證分), chungjajungbun(證自證分) connects with objects, perception, cognition, behavior too. The chinyeo-yeongi divide into smase(三細) and yukchu(육추), the samse consist of mumyungupsang(無 明業相), nungyunsand(能見相), kyungyesand(境界相) and the yukchu consist of chisang(智相), sangsoksang(相續相), chipchisang(執取相), kyemyungjasang(計明字相), kiupsang(起業相), upgyegosang(業繫苦相). These elements are relates with the concept of western environmental psychology from objects to behavior too. Pupkye-yeongi represent a characteristic of objects itself rather than a process of environmental cognition. However this study has limitations that the religion and scientific methods should be compare. sack(色) : an elements of it's derivation, all kinds of material soo(受) : a function of reception, feeling sang(想) : a representation of a thought in the mind hang(行) : mental operation sik(識) : a function of judgement sangbun(相分) : the thing in itself kyunbun(見分) : a reflection in the mind chajungbun(自證分) : confirmation of kyunbun chungjajungbyn(證自證分) : self-consciousness through self-examination mumyungupsang(無明業相) : a state of mixture with the object and the subject nungyunsang(能見相) : an operation of the subject kyungyesang(境界相) : a formation of object chisang(智相) : the beginning of distinction sangsoksang(相續相) : a judgement chipchisang(執取相) : a rsponse kiupsang(起業相) : have a influence to the next behavior upgyegosang(業界苦相) : retribution

• Tuberculosis and Respiratory Diseases
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• v.54 no.4
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• pp.378-385
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• 2003

Background : Wheezing is an important clue in the diagnosis of asthma. Previously, a Korean National asthma survey used a written questionnaire, containing the question, "Have you ever experienced a breathing sound-like 'sack-sack' or a flute sound (the Korean description for wheezing) during the last 12 months?" The response to this question showed a large discrepancy between the prevalence of wheezing and physician diagnosed asthma. This might have resulted partly from a misunderstanding of the question, due to an inadequate description for wheezing. This study was aimed at finding how well the layman understands the term "wheezing" when described as a breathing sound-like 'sack-sack', a whistle or a flute. Subjects and method : Sixty subjects, without experience of wheezing(group I), and 45 subjects, with chronic cough alleging wheezing(group II), were recruited from the Hallym University's Sacred Heart Hospital, in Anyang, Korea. Four different breathing sounds; vesicular, wheezing, tracheobronchial and crackle, were played for the subjects, without any experience with wheezing, and they were asked "which sound is most like that you would imagine when asked about a breathing sound-like 'sack-sack', a whistle or a flute?" This was followed by replaying the true wheezing sound, and then a global assessment was requested for the concordance between the real wheezing sound and the imagined wheezing sound. The wheezing sound was played for those subjects alleging wheezing, and they were asked, "have you really experienced that sound". Results : Only 46.7% of group I answered correctly, with 13.3% choosing the vesicular sound, 16.7% the tracheobronchial sound, 5.0% the crackle and 18.3% failed to answer. The concordance between their imagined wheezing and the real sound was $69.3{\pm}22.4%(mean{\pm}S.D.)$. 77.8% of group II recognized the correct sound as the one they had experienced. Conclusions : Language is not sufficient to the layman for describing natural sounds, such as wheezing.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.8A
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• pp.1177-1185
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• 2000

In this paper, We report on the performance issues faced by TCP based applications on satellite link having long propagation delay and high probability of bit erros and propose ENA(Error Notification Ack) algorithm for TCP Performance Enhancement. TCP Protocol cannot distinguish errored segments(in noisy medium) from losses of genuine network congestion and react as if there is network congestion. Therefore, Slow Start and Congestion avoidance mechanism are initiated. It happen this case in satellite link. Therefore it reduce the transmission rate and drop the performance. So, in this paper We propose ENA algorithm which is distinguished errored segments from losses of network congestion. And We propose the method of algorithm's implementation. And We evaluate the Performance of Tahoe, Reno, Sack TCP with ENA. As results, TCP Performance is better.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.8B
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• pp.699-706
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• 2008

This paper compares throughput performance of TCP and SCTP in a variety of network environments. For experiments, we construct a Linux-based testbed and consider a set of performance metrics such as MSS(Maximum Segment Size), transmission delay, and packet loss rate. In addition, we analyze the effect of SCTP multi-streaming on throughput. From the experimental results, we can see that SCTP provides throughput gain of approximately $20%{\sim}50%$ over TCP. This performance gain comes from the distinctive features of SCTP such as chunk bundling, initial congestion window of 2 MTU and SACK(Selective ACK) based error control. In the lossy networks, we can see that SCTP multi-streaming transmissions can effectively overcome the so-called HoLB(Head-of-Line Blocking) phenomenon of TCP.

• Korean Journal of Medicinal Crop Science
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• v.16 no.3
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• pp.188-191
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• 2008

Poncirus trifoliata Rafinesque has been used as the immature fruit of the trifoliate orange tree. This study was carried out to investigate the quality change of Poncirus trifoliata Rafinesque depending on packing materials (vacuum packing, PP (polypropylene) packing, gunny sack packing), storage places and storage periods up to 12 months. The change of loss on drying content, content of poncirin were measured during the 12 months. As a result, the loss on drying content was decreased rapidly in gunny sack packing after storage of 12 months at room temperature. The content of poncirin was decreased generally according to storage conditions and its average loss percent was 38.8%.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.38 no.1
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• pp.69-78
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• 2002

In order to examine the directional suitability of the axis direction of the fishing gear against the current, the experiments were carried out at the bamboo weir in Samchunpo water area from January, 2000 to September, 2001 The results of the study are as follows: In the experimental fishing gear constructed in the "V" shape, the range between two reference piles located at the entrance was 2.5m. The direction of bamboo weir′s axis was 355.5$^{\circ}$ The length of the left wing and those from the reference pile to the starting point of a curve were 106.0m, 7.5m, respectively. The length of the right wing and those from the reference pile to the starting point of a curve were 79.0m, 10.0m, respectively. Depths around the left and right stone wall that drove the steel pile were 5.0~6.5m and 6.5~9.5m, respectively. Also, depths on the bamboo weir′s axis and around the sack were 7.0~8.0m and about 8.0m, respectively. The maximum height of stone walls at the point of the left wing, the right wing and around the sack on the bamboo weir\` axis were 3.0m, 4.7m and 4.0m, respectively, Widths of stone walls at the point of both of the wings and around the sack on the bamboo weir\`s axis were 10.0~l4.0m, 22.0~25.0m, respectively. The averaging current direction on ebb tide was measured two times and it was 169.2$^{\circ}$ but the direction had about a 6.3$^{\circ}$ difference from the bamboo weirs axis. The maximum current speed appeared two to three hours later from the time of high tide and the current speed over 80.0cm/s lasted during about two Hours on the ebb tide In the case of a straight type wing In the bamboo weir, the eddy out of the left wing was comparatively big and the current on the right side from the bamboo weir′s axis had a tendency in turning to the right wing side. But in the case of a curve type wing, the eddy and tendency reduced significantly. It was thought that the experimental fishing gear was set suitably from the result of this simulation.