• Journal of Internet Computing and Services
• /
• v.20 no.6
• /
• pp.11-20
• /
• 2019

Numerous enterprises, organizations and individual users are exposed to large DDoS (Distributed Denial of Service) attacks. DDoS attacks are performed through a BotNet, which is composed of a number of computers infected with a malware, e.g., zombie PCs and a special computer that controls the zombie PCs within a hierarchical chain of a command system. In order to detect a malware, a malware detection software or a vaccine program must identify the malware signature through an in-depth analysis, and these signatures need to be updated in priori. This is time consuming and costly. In this paper, we propose a botnet detection scheme that does not require a periodic signature update using an artificial neural network model. The proposed scheme exploits Word2Vec and accelerated hierarchical density-based clustering. Botnet detection performance of the proposed method was evaluated using the CTU-13 dataset. The experimental result shows that the detection rate is 99.9%, which outperforms the conventional method.

• Journal of Internet Computing and Services
• /
• v.13 no.4
• /
• pp.83-93
• /
• 2012

HTML5 has developed not to have browser dependancy considering interoperability as same as maintaining compatability with lower versions of HTML. HTML5, the newest web standardization is on going of being structured. Along with the smart phone boom, HTML5 is spotlighted because it can be applied to cross platforms in mobile web environments. Specially the local Storage that has been listed in new features in HTML5 supports offline function for web application that enables web application to be run even when the mobile is not connected to 3G or wifi. With Local storage, development of server-independent web application can be possible. However Local storage stores plaintext data in it without applying any security measure and this makes the plaintext data dangerous to security threats that are already exist in other client side storages like Cookie. In the paper we propose secure Local storage methods to offer a safe way to store and retrieve data in Local storage guaranteeing its performance. Suggested functions in this paper follow localStorage standard API and use a module that provide cryptographic function. We also prove the efficiency of suggested secure Local storage based on its performance evaluation with implementation.

• Journal of Life Science
• /
• v.31 no.7
• /
• pp.671-676
• /
• 2021

A cDNA encoding the protein lethal (2) essential for life [l(2)efl] was cloned from Gryllus bimaculatus and named GBl(2)efl. This protein is composed of 189 amino acids, including an N-glycosylation site and 15 phosphorylation sites. Its predicted molecular mass is 21.19 kDa, with a theoretical isoelectric point of 6.2. The secondary structure of GBl(2)efl was predicted from the identification of random coils (56.08%), alpha helices (22.22%), extended strands (17.99%), and beta turns (3.7%) through sequence analyses. A homology analysis revealed that GBl(2)efl exhibited a high similarity with other species at the amino acid level, ranging from 52% to 69%. While GBl(2)efl mRNA expression was higher in the dorsal longitudinal flight muscle following a three-day starvation and in the Malpighian tubules following a one-day starvation, no changes in expression were detected in other tissues. Furthermore, tunicamycin-induced endoplasmic reticulum (ER) stress resulted in an approximately 1.8-fold higher expression in the fat body compared with the wild type.

• The Journal of Engineering Geology
• /
• v.32 no.4
• /
• pp.643-659
• /
• 2022

Geologic sequestration technologies such as CCS (carbon capture and storage), EGS (enhanced geothermal systems), and EOR (enhanced oil recovery) have been widely implemented in recent years, prompting evaluation of the mechanical stability of storage sites. As fluid injection can stimulate mechanical instability in storage layers by perturbing the stress state and pore pressure, poroelastic models considering various injection scenarios are required. In this study, we calculate the pore pressure, stress distribution, and vertical displacement along a surface using commercial finite element software (COMSOL); fault slips are subsequently simulated using PyLith, an open-source finite element software. The displacement fields, are obtained from PyLith is transferred back to COMSOL to determine changes in coseismic stresses and surface displacements. Our sequential use of COMSOL-PyLith-COMSOL for poroelastic modeling of fluid-injection and induced-earthquakes reveals large variations of pore pressure, vertical displacement, and Coulomb failure stress change during injection periods. On the other hand, the residual stress diffuses into the remote field after injection stops. This flow pattern suggests the necessity of numerical modeling and long-term monitoring, even after injection has stopped. We found that the time at which the Coulomb failure stress reaches the critical point greatly varies with the hydraulic and poroelastic properties (e.g., permeability and Biot-Willis coefficient) of the fault and injection layer. We suggest that an understanding of the detailed physical properties of the surrounding layer is important in selecting the injection site. Our numerical results showing the surface displacement and deviatoric stress distribution with different amounts of fault slip highlight the need to test more variable fault slip scenarios.

• Analytical Science and Technology
• /
• v.25 no.3
• /
• pp.178-189
• /
• 2012

As phthalates classified as toxic to reproduction category 2 and endocrine disrupting chemicals were more strictly regulated as Substances of Very High Concern (SVHC) for authorization in under EU REACH and considered as priority substances in RoHS II, standardization of phthalate testing method is now being proposed in IEC 62321 of IEC TC 111 and the 2nd revision of KS M 1991 is also finished. In order to assist standardization activities related to phthalating testing, solvent extraction part of existing national standards were compared and verified. Recovery of DEHP (diethylhexyl phthalate) from PVC (polyvinyl chloride) by Soxhlet extraction increased in the order of methanol, toluene, dichloromethane and hexane from 46.9% to 95.3% as measured by GC-MS. Optimum extraction time was verified to be 6 hours using hexane. Recovery of DBP (dibutyl phthalate), BBP (butylbenzyl phthalate), and DEHP from different matrixes such as PVC, nitro cellulose, ABS (acrylonitrile butadiene styrene). and EPDM(ethylene propylene diene monomer) rubber were evaluated to be more than 90% up to 99%. The detection limits of phthalates in solvent extraction followed by GC-MS analysis were 0.08~0.3 ${\mu}g/mL$ in solution and 8~30 mg/Kg in polymeric samples. GC-MS analyses of phthalates were carried out using different solvent extraction based on the EN 14372, ASTM D 7083, Japanese test method (MHLW 0906-4) and KS M 1991, proving that equivalent recoveries ranging from 98%~99% were obtained. DBP and DEHP were detected in three consumer products such as a child toy, a power cable and manicure with the amount of 22~1,910 mg/kg.

• Korean journal of food and cookery science
• /
• v.26 no.2
• /
• pp.198-205
• /
• 2010

In this study, the effect of added cashew nuts on the quality characteristics of pound cake were investigated. The weight and volume of the cake increased with the addition of cashew nuts concentration, whereas the dough yield and baking loss decreased. Furthermore, the hardness, penetration and, degree of retrogradation significantly decreased during storage with the addition of cashew nuts. As the cashew concentration was increased, the lightness and redness values of the crumb decreased and the yellowness values increased. In terms of sensory evaluation, when compared to the control group, the cashew nuts pound cake was superior in taste, flavor, chewiness and overall acceptability.

• Korean journal of food and cookery science
• /
• v.22 no.6 s.96
• /
• pp.808-814
• /
• 2006

The effects of vegetable oils addition on the quality characteristic of pound cake were investigated. The volume of pound cake prepared by adding vegetable oils increased from 1005.8 to 1075.8 mL, compared to 752.8 mL for the control. The volume index of pound cake prepared by adding vegetable oils increased by 3.46${\sim}$3.65, compared to 2.88 for the control. The hardness and penetration of pound cake with added vegetable oils were decreased significantly compared to those of the control during storage for 72 hours. The texture of pound cake with added vegetable oils was not decreased compared to that of the control. The lightness and yellowness values of the cake increased and the redness values of the cake decreased by adding vegetable oils compared to those of the control. The sensory quality of the pound cake with added vegetable oils, as estimated by color, taste, moistness and overall acceptability, was better than that of the control.

• Archives of design research
• /
• v.18 no.3 s.61
• /
• pp.129-138
• /
• 2005

It has been assumed that the clarification of a message is a necessary element for successful communication. However, in the today's complicated and changing environment of business marketing media, it is shown that the clarification of the message of advertisement may inhibit the effectiveness of communication. This study was to examine what was effective communication in advertisement when the company, provoking the people's negative emotional response, needs to establish new identities such as the goals and the special fields of business. In particular, the study was to investigate what effect the advertising strategy of strategically emitting ambiguous messages makes on the consumer's recognition, emotional attitude, reliability, and attitude towards the company. It was hypothesized that an ambiguous message in an advertisement has an effect on the consumer's recognition, emotional attitude, reliability, and attitude towards the company. Three texts from the 'Imagination Praises' campaign of KT&G which has been in process since 2003 were systematically sampled and the survey was performed by the means of questionnaires made on the sample The results showed that the ambiguous message of advertising texts gained better responses on the consumer's attention, good impression, affirmation, memory, sympathy than the dear message and that the ambiguous message had an effect on the consumer's attitude towards the advertisement itself. Thus, it could be tentatively concluded that the ambiguous message could be more effective in recognition and recall to promote the changes of identities of the company having the people's unfavorable emotion. But there wasn't any evidence that an ambiguous message in an advertisement was more effective in terms of the consumer's emotional response, reliability, and attitude towards the company. From this, it could be inferred that the receiver had an uncomfortable, doubtful and negative attitude about the implicit expressive code contained in the message. In the future deeper qualitative studies can compensate for the limited explanation of this empirical study focused on statistical analyses.