• Journal of the Korea Institute of Information Security & Cryptology
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• v.12 no.6
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• pp.125-135
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• 2002

The electronic payment system based on blind signature is susceptible to the blackmailing attack as opposed to keep the lifestyle of users private. In this paper. we suggest an efficient electronic cash system using a blind XTR-DSA scheme, which improves the method of defeating blackmailing in online electronic cash systems of ［6,9］. In case of blackmailing, to issue the marked coins we use the blind XTR-DSA scheme at withdrawal. In ［6,9］, to cheat the blackmailer who takes the marked coins the decryption key of a user had to be transferred to the Bank. But in our proposed method the delivery of the decryption key is not required. Also, in the most serious attack of blackmailing. kidnapping, we can defeat blackmailing with a relatively high probability of 13/18 compared with 1/2 in ［9］ and 2/3 in ［6］. If an optimal extension field of XTR suggested in ［7］ is used, then we can implement our system more efficiently.

• Journal of Platform Technology
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• v.9 no.4
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• pp.90-96
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• 2021

Most of the vehicles currently under development and in operation are equipped with various IoT sensors, but some of the factors that cause car accidents are relatively difficult to detect. One of the major risk factors among these factors is black ice. Black ice is one of the factors most likely to cause major accidents, as it can affect all vehicles passing through areas covered with black ice. Therefore, black ice detection technique is essential to prevent major accidents. For this purpose, some studies have been carried out in the past, but unrealistic factors have been reflected in some parts, so research to supplement this is needed. In this paper, we tried to detect black ice by analyzing color images using the CNN technique, and we succeeded in detecting black ice to a certain level. However, there were differences from previous studies, and the reason was analyzed.

• Korean Journal of Food Science and Technology
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• v.54 no.4
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• pp.398-402
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• 2022

Black chokeberry (Aronia melanocarpa), a rich source of polyphenols, exerts hypocholesterolemic effects. However, little is known about its effects on the regulation of the hepatic cholesterol metabolism and the underlying mechanisms. In the present study, the effects of polyphenol-rich black chokeberry extract (CBE) on hepatic cholesterol metabolism were investigated by measuring the expression of genes involved in the absorption, de novo synthesis, and efflux of cholesterol in HepG2 cells. There was a significant reduction in the expression levels of genes involved in cholesterol metabolism, the low-density lipoprotein receptor, 3-hydroxy-3-methylglutaryl coenzyme A reductase, and sterol regulatory element-binding protein 2, in CBE-treated HepG2 cells. Meanwhile, CBE increased the expression levels of genes involved in cholesterol and bile acid efflux. The expression levels of mitochondrial fatty acid oxidation genes increased, whereas those of lipogenic genes decreased following CBE treatment. These data suggest that the consumption of black chokeberry may be beneficial for the prevention of hypercholesterolemia.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.1
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• pp.71-76
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• 2013

In this paper, end-to-end performances for some VoIP traffics are measured and analyzed over MANET(Mobile Ad-hoc Networks) with packet aggregation transmission under blackhole attacks. A VoIP simulator based on NS-2 is used for performance measure. In the simulation, MOS, call connection ratio, network delay and packet loss rate are measured for end-to-end transmission performance. With analysis of measured data, characteristics of each traffics for performance parameters of packet aggregation transmission is showed on MANET under blackhole attack, As a results of this paper, some considerations be required for packet aggregation transmission are suggested to implement VoIP services on MANET under blackhole attacks.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.8
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• pp.4028-4032
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• 2013

Recycling method for pyrolyzed carbon black from pyrolysis process of waste tires is needed. Carbon black from pyrolysis of waste tires was used to modify and improve the permanent deformation properties of asphalt binder. 0%, 5%, 10%, 15% and 20% of pyrolyzed carbon black was mixed. Couple of laboratory tests, such as softening point, flash point test, rotational viscometer test and dynamic shear rheometer test, were carried out. The use of pyrolyzed carbon black incresed the softening point, rotational viscosity at 135oC, and resistance of permanent deformation.

• Applied Chemistry for Engineering
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• v.5 no.6
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• pp.935-942
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• 1994

Two types of ABS were prepared from diffrent types of rubber, and blends of the ABS and PMMA were compounded and evaluated in terms of morphology, mechaincal and rheological properties. In addition, the effect of carbon black in the ABS/PMMA blends were studied. With increasing PMMA content, flexural modulus, tensile yield strength, and surface gloss of the blends increased, but elongation at break and Izod Impact strength decreased. With carbon black addition, mechanical properties were generally decreased. Effects of the type of ABS, and carbon black on melt properties were also studied.

• Composites Research
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• v.17 no.5
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• pp.68-77
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• 2004

The electromagnetic (EM) absorption or shielding characteristics of a material is an important issue not only for military purpose but also for commercial purposes such as radar, electric or telecommunication devices. In order to design the effective electromagnetic wave absorber, the electromagnetic characteristics of the constituents of the material should be available in target frequency band. Also, it must be possible to predict the electromagnetic properties of absorbers with respect to the content of lossy ingredients. In this study, the dielectric properties of unsaturated polyester resins containing nano-size conductive carbon black powder were measured with a free space method in the X-band frequency range and analyzed with respect to the content of carbon black. Finally, the method for estimating the dielectric properties of polymeric resin containing conductive carbon black with respect to the EM frequency was developed and verified.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.1
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• pp.241-249
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• 2017

Recently, as a vehicle black box device has propagated, it has been increasingly used as a legal proof and there are the needs to verify an integrity of the video data. However, since the black box classified as the embedded system has a small capacity and low processing speed, there are limitations to the storage of video files and the integrity verification processing. In this paper, we propose a novel method for video files integrity in the black box environment with limited resources by using lightweight hash function LSH and the security of HMAC. We also present the test results of CPU idle rate at integrity verification in vehicle black box device by implementing this method, and verify the effectiveness and practicality of the proposed method.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.5
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• pp.1079-1084
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• 2018

The vehicle's black box is not suitable for bicycle black box because they contain sensors that are not suitable for bicycle black box. Therefore, this study implemented a system for viewing a video with a mobile phone as the slope changes. The angle was measured by using the gyro sensor and this angle was saved based on the angle setting on the raspberry pi. It has developed a system that allows users to download saved video files through mobile phone applications via FTP.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.10a
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• pp.66-69
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• 2010

Lately, vehicle combined vehicle and IT(Information Technology) for vehicle's safety and convenience. so, vehicles is equipped with many ECU(Electronic control unit). the ECU's transmit data about each electronic control unit with OBD(On-Board Diagnostics) Network and data about each multimedia with MOST(Media Oriented System Transport) Network. In this paper, Supplementing disadvantage of existing blackbox, Using MOST of in-vehicle multimedia network and OBD-II of in-vehicle control network, blackbox system obtain the vehicle's driving state data. so, blackbox system judge vehicle's driving state and provide vehicle's driving state information to driver. Blackbox system implement the features mentioned above. as a result, blackbox is going to be more accurate blackbox system.