• Korean Chemical Engineering Research
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• v.48 no.5
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• pp.668-671
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• 2010

A lab scale distillation experiment is conducted with small size packing used in lab scale multi-tray distillation equipment for the performance evaluation of distillation system. A sufficient surface are yielded with 6.7 mm cylindrical packings made of stainless steel, and a good liquid holdup and residence time are resulted. The comparison between the theoretical tray from the HYSYS and the experimental distillation outcome indicates that a 7 cm HETP from 27 cm packing height and a 8 cm HETP from 45 cm packing height are obtained. Comparing with the 8 cm HETP of commercial structured packing shows a similar experimental results obtained here. The 7 cm HETP is available with a complete insulation, and the importance of the insulation is proved. The results of this study indicates that a practical distillation column used in field can be tested in lab.

• Journal of Navigation and Port Research
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• v.28 no.6
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• pp.531-539
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• 2004

In this paper, we propose a new heuristic solution for 3D container packing problem for the variable sizes and types of freight. Frist of all, we consider the total cost of container charge i.e., handling, loading and transportation, where each freight will be specifically identified The types of containers and its number to be loaded am be selected automatically by minimizing the total cost of container charge. Maximization of loading space am be achieved efficiently by operating the palletizing and/or depalletizing of freight. By considering these factors we can determine the position of freight in the container and the loading sequence to be packing into the container. In container packing simulation, we can verify that the proposed heuristic algorithm indicates more efficiency space utilization and shows the possibility of using on commercial business.

• Journal of Advanced Navigation Technology
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• v.16 no.3
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• pp.488-494
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• 2012

This paper classifies the self-defense techniques used by the malicious software based on their approaches, introduces the packing technique as one of the code protection methods and proposes a way to quickly analyze the packed malicious codes. Packing technique hides a malicious code and restore it at runtime. To analyze a packed code, it is initially required to find the entry point after restoration. To find the entry point, it has been used reversing the packing routine in which a jump instruction branches to the entry point. However, the reversing takes too much time because the packing routine is usually obfuscated. Instead of reversing the routine, this paper proposes an idea to search some features of the startup code in the standard library used to generate the malicious code. Through an implementation and a consequent empirical study, it is proved that the proposed approach is able to analyze malicious codes faster.

• The Journal of Information Systems
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• v.28 no.4
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• pp.1-25
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• 2019

Purpose The purpose of this study is to investigate cognitive mechanism of goal relations (Single-goal vs. Multiple-goals) and to-do list (Packing vs. Unpacking) and also verify the role of self-efficacy in the perspective of motivation belief. The perspective of cognitive mechanism is related to the effects of how the relations of multitasking environments affects to facilitating relation or conflicting relations. In pursuit of a single goal, judgement of task importance can be facilitated by unpacking effect due to relations of strongly associated project components including to-do list. On the other hands, in pursuit of multiple goals, judgement of task importance can be conflicted due to mutually exclusive relations of multiple goals. Additionally, the cognitive mechanism can be regulated from the role of self-efficacy, which contributes to motivation belief on how much a person is confident in achieving given tasks. In the end this research is to identify self-efficacy as boundary condition in inhibiting the effects of facilitation and conflict. Design/methodology/approach This study conducted Two-way ANOVA (Packing/ Unpacking * Single-goal/ Multiple-goals) to explore the effects of cognitive mechanism on task importance. After that we performed Three-way ANOVA, 2 (To-do list: Packing/ Unpacking) * 2 (Goal relation: Single-goal/ Multiple-goals) * 2 (Self-efficacy: Low self-efficacy/ High self-efficacy) to verify the role of self-efficacy between goal relations and to-do list. Findings In the cognitive mechanism, the task importance is not significantly different between in packed and in unpacked condition in pursuit of a single goal. But multitasking with multiple goals causes goal conflict, which means packed condition indicates significantly higher task importance than unpacked condition. Additionally, for a group with low self-efficacy unpacking leads to conflicting relation, which implies that packed condition is more efficient strategy than packed condition. On the other hands, in pursuit of mulitple goals, either packing or unpacking has no distinctive effects on task importance. However, participants with high self-efficacy are no longer affected by facilitating relation and conflicting relation as well in pursuit of either a single goal or multiple goals as well.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.12
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• pp.751-756
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• 2017

A molding-type power inductor is an inductor that uses a hybrid material that is prepared by mixing a ferrite metal powder coated with an insulating layer and an epoxy resin, which is injected into a coil-embedded mold and heated and cured. The fabrication of molding-type inductors requires various techniques such as for coil formation and insertion, improving the magnetic properties of soft magnetic metal powder, coating an insulating film on the magnetic powder surface, and increasing the packing density by well dispersing the powder in the epoxy resin. Among these aspects, researches on additives that can disperse the metal soft magnetic powder having the greatest performance in the epoxy resin with high charge have not been reported yet. In this study, we investigated the effect of silanes, KBM-303 and KBM-403, and a commercial dispersant on the dispersion of metal soft magnetic powders in epoxy resin. The sedimentation height and viscosity were measured, and it was confirmed that the silane KBM-303 was suitable for dispersion. For this silane, the packing density was as high as about 72.49%. Moreover, when 1.2 wt% of dispersant BYK-103 was added, the packing density was about 80.5%.

• Journal of Digital Contents Society
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• v.15 no.3
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• pp.373-380
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• 2014

Malicious codes uses generic unpacking technique to make it hard for analyzers to detect their programs. Recently their has been several researches about generic packet to prevent or detect these techniques. And they try to focus on the codes that repeats while generic packing is doing compression because generic packing technique executes after it is decompressed. And they try to focus on the codes that repeats while generic packing is doing compression because generic packing technique executes after it is decompressed. Therefore, this makes a interesting performance which shows a similar address value from the codes which are repeated several times what is different from the normal program codes. By dividing these codes into regularly separated areas we can find that the generic unpacking codes have a small entropy value compared to normal codes. Using this method, it is possible to identify any program if it is a generic unpacking code or not even though we do not know what kind of algorithm it uses. This paper suggests a way of disarming the generic codes by using the low value entropy value which comes out from the Opcode addresses when generic unpacking codes try to decompress.

• Archives of Plastic Surgery
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• v.39 no.6
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• pp.612-617
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• 2012

Background Packing after closed reduction of a nasal bone fracture causes inconvenient nasal obstruction in patients. We packed the superior meatus with Vaseline gauze to support the nasal bone, and packed the middle nasal meatus with a Doyle Combo Splint consisting of an airway tube, a silastic sheet, and an expandable sponge to reduce the inconvenience. In addition, we aimed to objectively identify whether this method not only enables nasal respiration but also sufficiently supports the reduced nasal bone. Methods Nasal ventilation was measured via spirometry 1 day before surgery and compared to 1 day after surgery. To compare support of the reduced nasal bone by the 2 methods, 2 plastic surgeons assessed the displacementon X-rays taken after the surgery and after removing the packing. The extent of nasal obstruction, dry mouth, sleep disturbance, headache, and swallowing difficulty were compared with visual analog scales (VAS) on a pre-discharge survey. Results In the experimental group, the nasal respiration volume 1 day after surgery remained at $71.3%{\pm}6.84%$ on average compared to 1 day prior to surgery. Support of the reduced bone in the experimental group ($2.80{\pm}0.4$) was not significantly different from the control group ($2.88{\pm}0.33$). The VAS scores for all survey items were lower in the experimental group than in the control group, where a lower score indicated a lower level of inconvenience. Conclusions The nasal cavity packing described here maintained objective measures of nasal respiration and supported the reduced bone similar to conventional methods. Maintaining nasal respiration reduced the inconvenience to patients, which demonstrates that this packing method is useful.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.10
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• pp.1935-1942
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• 2017

Recently, a compression algorithm is widely used as a method for compressing geographic information data. However, such a compression algorithm has a problem that the continuity of the map data is insufficient to actually apply it to the geographic information data compression, and the compression rate is lowered because it can not be compressed into a single data. Therefore, in this paper, we have designed and implemented a Run-Length / Byte-Packing compression algorithm that enables compression of geographic information by combining the advantages of compression algorithms and improves compression and restoration speed. As a result of evaluating the implemented algorithm, it was confirmed that the proposed algorithm improved about 5% on average compared with the existing compression algorithm, and it was confirmed that the compression rate and the restoration speed were improved.

• Archives of Plastic Surgery
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• v.36 no.2
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• pp.242-246
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• 2009

Purpose: The majority of nasal bone fractures have been managed by routine procedure of closed reduction and intranasal packing. However, nasal packing can cause nasal injury, hypoxia and patient's discomfort. And, synechiae formation is a frequently occurred after the nasal surgery. Various methods are used to reduce the incidence of synechiae formation. The purpose of this study was to compare routine procedure and nasal packing with reverse "U" shaped silicone sheet with respect to postoperative nasal synechiae formation and final outcome. Methods: We analyzed the medical records of 100 patients with nasal bone fracture who were operated by closed reduction in the last one year. The silicone sheet was designed in reverse "U" fan - shape and inserted between the middle turbinate and the septal wall. Nasal packing was removed at two days after the operation, and silicone sheet was removed at 10 to 14 days. Results: Synechiae in the middle meatus developed in 2 of 75 patients. Although synechiae between the middle meatus and nasal septum occurred in patients, the patients did not complaint of any olfactory disturbance and nasal obstruction. Conclusion: The reverse "U" fan - shape silicone sheet caused less pain for patients and no significant differences in outcome were found. The results of this study suggest that insertion of silicone sheet between the middle meatus and septum can be a useful method in the prevention of intranasal synechiae formation. The reverse "U" silicone sheet is a good alternative for routine packing methods.

• Korean Chemical Engineering Research
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• v.50 no.1
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• pp.66-71
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• 2012

We deal with a problem to determine experimentally as well as theoretically permeability of incompressible viscous flow through packed bed of bidisperse hard spheres in size. For the size ratios of large to small spheres ${\lambda}$=1.25 and 2, we set up bidisperse packing and measured porosity and permeability at various volumetric ratios of small to large spheres ${\gamma}$. Bidisperse packing shows lower porosity and permeability than monodisperse packing does. Variation of porosity as a function of ${\gamma}$ does not match with that of permeability. A theoretical expression for predicting permeability of a viscous flow for packed bed of bidisperse packing is derived based on calculation of drag force acting on each sphere and its predictions are compared with the experimental data and those from some relations previously suggested. It is found that our theory shows better agreement with experimental results than the previous studies and is proved to be quite simple and accurate in estimating the permeability.