• Steel and Composite Structures
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• v.14 no.1
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• pp.21-39
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• 2013

The paper presents a numerical investigation, done with the computer program SAFIR, in order to obtain simpler finite element models for representing the behaviour of the partially protected composite steel concrete slabs in fire situations, considering the membrane action. Appropriate understanding and modelling of the particular behaviour of composite slabs allows a safe approach, but also substantial savings on the thermal insulation that has to be applied on the underlying steel structure. The influence of some critical parameters on the behaviour and fire resistance of composite slabs such as the amount of reinforcing steel, the thickness of the slab and the edge conditions is also highlighted. The results of the numerical analyses are compared with the results of three full scale fire tests on composite slabs that have been performed in recent years.

• The Journal of Advanced Prosthodontics
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• v.13 no.2
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• pp.79-88
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• 2021

Purpose. To assess peri-implant stress distribution using finite element analysis in implant supported fixed partial denture with occlusal schemes of cuspally loaded occlusion and implant protected occlusion. Materials and methods. A 3-D finite element model of mandible with D2 bone with partially edentulism with unilateral distal extension was made. Two Ti alloy identical implants with 4.2 mm diameter and 10 mm length were placed in the mandibular second premolar and the mandibular second molar region and prosthesis was given with the mandibular first molar pontic. Vertical load of 100 N and and oblique load of 70 N was applied on occlusal surface of prosthesis. Group 1 was cuspally loaded occlusion with total 8 contact points and Group 2 was implant protected occlusion with 3 contact points. Results. In Group 1 for vertical load, maximum stress was generated over implant having 14.3552 Mpa. While for oblique load, overall stress generated was 28.0732 Mpa. In Group 2 for vertical load, maximum stress was generated over crown and overall stress was 16.7682 Mpa. But for oblique load, crown stress and overall stress was maximum 22.7561 Mpa. When Group 1 is compared to Group 2, harmful oblique load caused maximum overall stress 28.0732 Mpa in Group 1. Conclusion. In Group 1, vertical load generated high implant stress, and oblique load generated high overall stresses, cortical stresses and crown stresses compared to vertical load. In Group 2, oblique load generated more overall stresses, cortical stresses, and crown stresses compared to vertical load. Implant protected occlusion generated lesser harmful oblique implant, crown, bone and overall stresses compared to cuspally loaded occlusion.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.99-100
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• 2006

Orthogonally protected block copolymers of based on p-hydroxystyrene were prepared with high control via nitroxy mediated radical polymerization using an alkoxyamine as an unimolecular initiator. Thin films of partially protected block copolymer were prepared by spin or dip coating. A well defined nanostructure could be observed as a result of phase separation e.g. cylinders in a matrix oriented perpendicular or parallel to the substrate. The nanostructure of the polymeric films can be defined by the block copolymer composition and it determines surface properties and allows further, selective functionalization, e.g. via click chemistry. The thin films can be designed in a way to allow a patterning based on a thermal or photochemical stimulus.

• Bulletin of the Korean Chemical Society
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• v.11 no.6
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• pp.534-538
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• 1990

Glucagon was found to interact with DMPC vesicles electrostatically and hydrophobically. It appears that glucagon bound irreversibly to the vesicles through hydrophobic interaction was partially protected from the proteolysis by trypsin. Out of three possible sites, only the peptide bond preceded by Arg-18 was cleaved by a prolonged trypsin treatment. ${\alpha}$-chymotrysin did not affect the vesicle-bound glucagon. Based on these observations, possible structure of irreversibly bound glucagon on the vesicle surface is discussed.

• Journal of Korean Society of Forest Science
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• v.101 no.2
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• pp.279-285
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• 2012

This study was conducted to offer preliminary data for forest management from March and December 2011. Based on the number of standing trees by DBH classes, it is recommended to practice thinning and pruning to change the current young stand to mature stand. In Livelihood Environment Forest Protected Areas, young (0-10 years or 0-10 cm DBH) and detected trees need to be removed and selected healthy trees need to be heavily tended. Also, selected trees in age 20-30 (20-30 cm DBH class) need to receive concentrated tending. Since Livelihood Environment Forest Protected Areas had been vulnerable for erosion, the diversity of understory layer is low. In order to diversify deciduous trees, it is recommended to introduce new species and thin and prune existing trees. It is not proper to adapt clear cutting in a short time and should be partially regenerated using shelter-wood method or proper tending practices to the Pinus rigida dominanted forest. Tending existing under-story species including Quercus alina, Quercus variabilis, and Quercus serrata would be important.

• Korean Journal of Radiology
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• v.20 no.8
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• pp.1285-1292
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• 2019

Objective: To evaluate the safety and efficacy of the coil-protected technique for liquid embolization in neurovascular malformations. Materials and Methods: Twenty-two patients who underwent coil-protected liquid embolization for symptomatic cranial (n = 13) and spinal (n = 9) arteriovenous fistula (AVF) or arteriovenous malformations (AVMs) were identified. A total of 36 target feeder vessels were embolized with N-butyl cyanoacrylate and/or Onyx (Medtronic). This technique was used to promote delivery of a sufficient amount of liquid embolic agent into the target shunt or nidus in cases where tortuous feeding arteries preclude a microcatheter wedging techniqu and/or to prevent reflux of the liquid embolic agent in cases with a short safety margin. The procedure was considered technically successful if the target lesion was sufficiently filled with liquid embolic agent without unintentional reflux. Angiographic and clinical outcomes were retrospectively evaluated. Results: Technical success was achieved for all 36 target feeders. Post-embolization angiographies revealed complete occlusion in 16 patients and near-complete and partial occlusion in three patients each. There were no treatment-related complications. Of the six patients who showed near-complete or partial occlusion, five received additional treatments: two received stereotactic radiosurgery for cerebral AVM, two underwent surgical removal of cerebral AVM, and one underwent additional embolization by direct puncture for a mandibular AVM. Finally, all patients showed complete (n = 19) or near-complete (n = 3) occlusion of the target AVF or AVM on follow-up angiographies. The presenting neurological symptoms improved completely in 15 patients (68.2%) and partially in seven patients (31.8%). Conclusion: The coil-protected technique is a safe and effective method for liquid embolization, especially in patients with various neurovascular shunts or malformations who could not be successfully treated with conventional techniques.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2006.11a
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• pp.307-312
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• 2006

Protection to the multimedia contents is inevitable to ensure that only authorized users be able to access the protected contents for consumption. Since protection mechanisms need to be designed efficiently by exploiting the type of the contents, we propose a protection scheme for the video bitstream encoded by Scalable Video Coding (SVC) technique. Our scheme exploits the property of SVC in which a video is encoded into spatial, temporal, and quality scalability layers. By applying our proposed protection scheme to the appropriate scalability layers we can effectively control the SVC contents completely or partially. Each layer can be flexibly protected with different encryption keys or even with different encryption algorithms. The algorithms that are used to protect each layer are described by the standardized protection description tool, which is the MPEG-21 Intellectual Property Management and Protection (IPMP) Components. In this paper, we present the design of the proposed layered SVC protection scheme, its implementation and experimental results. The experiment result shows that the proposed layered SVC protection scheme is very effective and can easily be applied.

• Applied Biological Chemistry
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• v.40 no.4
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• pp.277-282
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• 1997

Acetolactate synthase (ALS) was partially purified from Escherichia coli MF2000/pTATX containing Arabidopsis thaliana ALS gene. The partially purified ALS was examined for its sensitivity toward various modifying reagents such as iodoacetic acid, iodoacetamide, N-ethylmaleimide (NEM), 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB), p-chloromercuribenzoic acid (PCMB), and phenylglyoxal. It was found that PCMB inhibited the enzyme activity most strongly followed by DTNB and NEM. Since iodoacetic acid did not compete with substrate pyruvate, it appeared that cysteine is not involved in the substrate binding site. On the other hand, the substrate protected the enzyme partly from inactivation by phenylglyoxal, which might indicate interaction of arginine residue with the substrate. The partially purified enzyme was inhibited by end products, valine and isoleucine, but not by leucine. However, the ALS modified with PCMB led to potentiate the feedback inhibition of all end products. Additionally, derivatives of pyrimidyl sulfur benzoate, a candidate for a new herbicide for ALS, were examined for their inhibitory effects.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.12
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• pp.88-93
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• 2000

The reduction of the cushion material such as Expanded Polystyrene (EPS) is one of the urgent tasks of the package design process in home electrical appliances considering environmental protection. EPS reduction often causes the structural damage of products, which must be protected in the environment of transportation. CAE simulation can help the efficient package design with low material cost. The mechanical drop simulation of packaged product was performed with commercial FEM code and Taguchi approach was used partially to determine the dominant design parameters. As results of this study, about 20% reduction of EPS was accomplished in the monitor package design.

• BMB Reports
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• v.28 no.2
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• pp.94-99
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• 1995

The properties of binding sites in the active site of $Zn^{2+}$-glycerophosphocholine cholinephosphodiesterase were examined using substrates and inhibitors of the enzyme. Phosphodiesterase hydrolyzed p-nitrophenylphosphocholine, p-aminophenylphosphocholine, and glycerophosphocholine, but did not hydrolyze either acylated glycerophosphocholine or bis (p-nitrophenyl)phosphate, suggesting a size limitation for interaction with a glyceryl moiety-binding subsite. The hydrolysis of p-nitrophenylphosphocholine was competitively inhibited by glycerophosphocholine and p-aminophenylphosphocholine, while glycerophosphoethanolamine was a weak inhibitor. The enzyme was also inhibited by choline, but not by ethanolamine. Thiocholine, a much more potent inhibitor than choline, was more inhibitory than cysteamine, suggesting a strict specificity of an anionic subsite adjacent to a $Zn^{2+}$ subsite. Of all oxyanions tested, the tellurite ion was found to strongly inhibit the enzyme by binding to a $Zn^{2+}$ subsite. The inhibitory role of tellurite was synergistically enhanced by tetraalkylammonium salts, but not by glycerol. Deactivation of the enzyme by diethylpyrocarbonate was partially protected by choline, but not by glycerophosphate. It is suggested that the active site of phosphodiesterase contains three binding subsites.