• Transactions of Materials Processing
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• v.7 no.4
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• pp.340-346
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• 1998

A kinematically admissible velocity field is developed for the analysis of twisting of the extruded products with elliptical shapes from round billet. The twisting of extruded product is caused by the lin-early increased rotational velocity from the center on the cross-section of the workpiece at the die exit. In the analysis the rotational velocity in angular direction is assumed by the multiplication of radial distance and angular velocity. The angular velocity is zero at the die entrance. The increase rate of angular velocity is determined by the minimization of plastic work. The results of the analysis show that the angular velocity of the extruded product in creases with the die twisting angle, the aspect ratio of product the friction condition, the reduction of area, and decreases with the die length.

• Food Science and Preservation
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• v.15 no.5
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• pp.617-621
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• 2008

Sequential passes through $Sephadex^{TM}$ columns were used to select phages that displays ligands for dextran ($\alpha$-1,6 linked linear chains) from a phage antibody library. Those phages that bound to the $Sephadex^{TM}$ in each iteration were replicated in E. coli. A phage preparation isolated on the third round selection produced 5.4 nephelos turbidity units (NTU) in a dextran specific immunonephelometric assay, a 2.2 fold higher value than the phage preparation from the first round selection. This phage gave $72\;{\pm}\;10$ normalized intensity (N.I.) in a dip-stick assay against high molecular size dextran (T2000, $2\;{\times}\;10^6) and significantly lower color ($30\;{\pm}\;6$ N.I.) against low molecular size dextran (T10, $10^4$). The presence of an Fab insert in each of these phages was confirmed using a $\beta-galactosidase linked assay and polymerase chain reaction.

• Journal of KIISE:Information Networking
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• v.28 no.4
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• pp.631-640
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• 2001

Round robin scheduling discipline, which is a sort of frame-based scheduling, is quite simple and straightforward for handling multiple queues, and by putting a different weight on each queue, a network can offer differentiated services such as different bandwidth, or delay bound. The most typical algorithm among this disciplines is the weighted round robin(WRR). Also, WRR algorithm can be implemented efficiently by dynamic binary scheduling wheel(DBSW) architecture. This paper performs the analysis of the DBSW architecture and compares the results with simulation results. The analysis data and simulation data show that the DBSW structure decreases average buffer length because it is capable of maintaining the allocated weight of each VC correctly.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.8
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• pp.1663-1668
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• 2005

There have been numerous researches regarding the QoS guarantee in packet switching networks. IntServs, based on a signaling mechanism and scheduling algorithms, suggesting promising solutions, yet has the crucial complexity problem so that not enough real implementations has been witnessed. Flow aggregation is suggested recently to overcome this issue. In order to aggregated flows fairly so that the latency of the aggregated flows is bound, however, a non-work conserving scheduler is necessary, which is not very popular because of its another inherent complexity. We suggest a non-work conserving scheduler, the Round Robin with Virtual Flow (RRVF), which is a variation of the popular Deficit Round Robin (DRR). We study the latency of the RRVF, and observe that the non-work conserving nature of the RRVF yields a slight disadvantage in terms of the latency, but after the aggregation the latency is greatly reduced, so that e combined latency is reduced. We conclude that the flow aggregation through RRVF can actually reduce the complexity of the bandwidth allocation as well as the overall latency within a network.

• Journal of Korean Society of Forest Science
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• v.90 no.4
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• pp.505-512
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• 2001

This study examined the impacts of tariff reductions on timber products in the new round of WTO negotiations on domestic timber products markets and presented the measures to minimize their impacts. Scenarios on reductions in tariffs were developed based on result of UR negotiation and prospective issues on scope of tariffs bound, base rates for negotiation, degree of tariff cuts, etc. emerged during preparatory meetings held to launch the New Round of WTO Negotiation. Korea Timber Market Model(KORTIMM) developed by Korea Forest Research Institute was used to simulate the impacts on forest products markets by scenario. It was estimated that their impacts on net imports would be much larger than those on both consumption and production. The results showed that their impacts on plywood market and on net imports of processed forest products would be much larger relatively but that their impacts on log market and on consumption and production of processed forest products would be less than 1 percent. It was estimated that log consumption would be reduced due to reduction in domestic production of processed products and thus both production and imports of logs would be reduced as well. In oder to minimize the impacts, efforts should be made to start negotiations to reduce tariffs with bound rates for bounded products and with applied rates for non-bounded products, to expand the implementation period and to maintain the status of developing country. In addition, it might be one of countermeasures to use legitimate measures consistent with WTO rules such as anti-dumping, countervailing measures and safeguards.

• Korean Journal of Veterinary Research
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• v.47 no.3
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• pp.309-314
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• 2007

A 7-year-old, intact female Korean Jindo dog was referred due to ataxia and pain on palpation of the thorax. Radiograph, echocardiography and computed tomogram revealed a mass on the heart base region and osteolytic change of fifth thoracic (T5) vertebra. At necropsy, a firm, encapsulated and round mass was seen arising from the heart base region surrounding the ascending aorta and pulmonary artery. Histopathologically, nests of cuboidal and polyhedral cells having abundantly granular and eosinophilic cytoplasm with round to oval nucleus were separated by fibrous septa. Immunohistochemistry using chromogranin A revealed that tumor cells were originated from neuroendocrine organ and metastasized into some organs including lung, spleen, liver, kidney and T5 vertebra. By electron microscopy, we found the electron-dense and membrane-bound granules in cytoplasm of the tumor cells. This study provides the uncommon evidence that aortic body tumor metastasized to both multiple organs and bone.

• Korean Journal of Optics and Photonics
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• v.10 no.5
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• pp.405-412
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• 1999

We propose an effective algorithm, which can predict the detailed behavior of the intensity-modulated high speed optical signal after propagating through an optical fiber. The alogrithm is based on the SSF (Split Step Fourier) Method, however, the step size is automatically calibrated in each calculation step to reduce the number of calculations within given round-off error bound. Applying the algorithm to the 2.5 Gbps 100 km transmission and 10 Gbps 40 km transmission simulations, we achieved the calculation time reduction by maximum 1/120 and 1/56 of the calculation time by using the SSF fixed step algorithm previously known. The root-mean-square of the round-off error was kept within -30 dB compared to the signal level throughout the calculation.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.12B
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• pp.847-854
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• 2005

Many of scheduling algorithms that provide a pre-defined bandwidth to a traffic flow fall into a category of Latency-rate (LR) server, the delay of whose network can be simply calculated by adding up individual 'latencies' of each LR servers. Deficit Round Robin (DRR) is one of such LR servers and the simplest one to implement, so that it is adopted in many real systems. In this research we suggest an improved version of DRR, the DRR with Instant Service (DRR-IS), and analyze it. We have proved that the DRR-IS is still an LR sewer and have obtained its latency. The DRR-IS, compared with DRR, turns out to have the same complexity while provide about $30\%$ better latency.

• International Journal of Internet, Broadcasting and Communication
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• v.14 no.3
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• pp.1-7
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• 2022

This paper aims to compare the mean object size of M/G/1/PS model with that of M/BP/1 model used in the web service. The mean object size is one of important measure to control and manage web service economically. M/G/1/PS model utilizes the processor sharing in which CPU rotates in round-robin order giving time quantum to multiple tasks. M/BP/1 model uses the Bounded Pareto distribution to describe the web service according to file size. We may infer that the mean waiting latencies of M/G/1/PS and M/BP/1 model are equal to the mean waiting latency of the deterministic model using the round robin scheduling with the time quantum. Based on the inference, we can find the mean object size of M/G/1/PS model and M/BP/1 model, respectively. Numerical experiments show that when the system load is smaller than the medium, the mean object sizes of the M/G/1/PS model and the M/BP/1 model become the same. In particular, when the shaping parameter is 1.5 and the lower and upper bound of the file size is small in the M/BP/1 model, the mean object sizes of M/G/1/PS model and M/BP/1 model are the same. These results confirm that it is beneficial to use a small file size in a web service.

• The Research Journal of the Costume Culture
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• v.5 no.4
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• pp.12-31
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• 1997

This is a study on the changes of the ancient underclothes. Underclothing includes all such articles, worn by either sex, as were completely or mainly concealed from the spectator by the external costume. Functions of underclothes are follow ; to protect the body from cold, to support the shape of the costume, to cleanliness, to erotic use of underclothes and as a method of class distinction. Linen is the oldest as materials and cotton came into general use after the Restoration of 1660. We must suppose that woolen petticoat was at least as old as the Middle Ages and silk was rarely used until late in Victorian times. Until the middle of the last century underclothes were necessarily hand-made, and the absence of fit was noticeable until the introduction of man\`s drawers, fitting the leg, at the close of the eighteen century. Strings and ribbons were the fastenings for underclothes until the middle of the seventeenth century, when they were replaced by buttons. One outstanding example of the first type of figures is a Babylonian girl of about 3000 BC from Sumeria who wears that today would immediately be described as briefs. Female statues show no trace of anything being worn under the chiton, but there is literary evidenced that the Greeks. A band of linen of kid was bound round the waist and lower torso to shape and control it. It was known as the Zone or girdle. The apodesmos, meaning a band, breast band, occurs in a fragment of Aristophanes. A Roman mosaic shows female athletes wearing a bikini-briefs and bra in the fourth century AD. A similar band, called the mastodeton, or breast band, was also worn round the bust, apparently to flatten or minimise it, as in the 1920s, and not, to stress its curves. In Rome, too, women sometimes wore bands of material round the hips and bust-a cestus or girdle is referred to by the poet Martial and seems to have been similar to the zone, but wider, and the strophium, or breast band, is mentioned by Cicero.