• Proceedings of the Korea Multimedia Society Conference
• /
• 2004.05a
• /
• pp.45-48
• /
• 2004

Diffie-Hellman(DH) 키공유 기법[1]이 제안된 후 많은 종류의 키공유 기법들이 연구되었으며, 특히 특정한 그룹 내의 구성원들이 안전한 통신을 할 수 있게 하기 위한 그룹 기반의 키공유 기법들이 제안되었다. 이러한 기법들은 PKI(Public Key Infrastructure) 등을 사용하는 여러 응용들에서 쉽게 사용될 수 있지만, ad-hoc통신망과 같이 특정한 기반구조를 사용할 수 없는 환경에서는 적용하기 어렵다. [2]에서는 ad-hoc 환경에서 사용할 수 있는 그룹(conference) 기반의 키공유 기법을 제안하였지만, n$^{+2}$ 라운드의 통신량이 요구되며, 그룹 구성원들의 위치정보와 같은 부가정보를 알고 있어야 하는 문제점이 있다. 본 논문에서는 ad-hoc 환경에서 그룹 구성원들의 위치정보를 알 필요 없는 효율적인 2-라운드 키공유 기법을 제안한다.

• Nutritional Sciences
• /
• v.2 no.2
• /
• pp.119-124
• /
• 1999

Food allergies play an important role in Atopic Dermatitis (AD). Dietary manipulation is essential in the management of AD. However, there has been a paucity of data reporting the prevalence of food allergies in AD patients in Korea. In this study, the Food Open Challenge Tests (FOCT) were conducted to investigate food allergies in AD patients. The skin-prick test and the detection of specific IgE, as well as allergy history of patient were used to detect food allergies in all AD patients. Elimination diet was conducted for two weeks prior to FOCTs. The prevalence of food allergies by FOCT is as follows: milk (67.3%); chicken (64.2%); pork (62.8%); eggs (61.0%); beef(55.4%) ; wheat (52.0%) and soybean (45.2%). Allergenic food items in Korean AD patients were different from people in other foreign countries. The seven major foods those tested positively by FOCTs were completely eliminated from the replaced diets for two weeks, and were subsequently reintroduced one at a time. Results from FOCTs were not comparable with allergy history or skin-prick tests or specific IgE detection. The sensitivity and specificity of skin-prick tests and specific IgE detection were lower than FOCTs. Allergy history, skin-prick tests, and specific IgE detection are useful for the identification of food allergen but its clinical significance differed according to food items. Therefore, we conclude that even though a 10-day delay was necessary after food challenge, FOCT is a useful and valid method to confirm food allergies and may be essential for the effective control of food allergies for treatment of AD.

• Journal of Nutrition and Health
• /
• v.54 no.5
• /
• pp.501-514
• /
• 2021

Purpose: The purpose of this study was to provide basic data for the management of atopic dermatitis (AD) in adults by analyzing the relationship between AD and intake of soft drinks in adults. Methods: This study was conducted on 5,931 adults aged 19 to 64 who completed the food frequency questionnaire (FFQ) for participants in the Korea National Health and Nutrition Examination Survey VII-3 and VII-1. Subjects were divided into an AD-diagnosed group and a non-AD group according to the diagnosis of AD. In addition, the group diagnosed with AD was divided into a 'symptom-AD' group and a 'no symptom-AD' group. The amount, frequency of intake, and nutritional status of soft drinks were analyzed using the FFQ. Results: Compared with the nutrient intake per 1,000 kcal of energy consumption, fat intake was higher in the AD-diagnosed group than in the non-AD group, and carbohydrate, dietary fiber, calcium, phosphorus, iron, potassium, vitamin A, thiamin, and vitamin C were lower in AD-diagnosed group. The daily intake of soft drinks and the percentage of 'more than 0.5 servings per day' were also higher in the AD-diagnosed group than in the non-AD group. Also, the frequency of the intake of soft drinks was significantly higher in the AD-diagnosed group than in the non-AD group. The odds ratio of AD symptoms due to the intake of soft drinks increased 2.6 times when the intake was 'less than 0.5 serving per day'. Conclusion: AD in adults appears to be related to malnutrition and excessive consumption of soft drinks, and the current prevalence of AD symptoms may also be related to the intake of soft drinks. Based on these results, we suggest that one of the ways to manage AD in adults would be to limit their intake of soft drinks.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.8 no.2
• /
• pp.371-388
• /
• 2014

Cognitive Radio (CR) has been recently proposed as a promising technology to remedy the problems of spectrum scarcity and spectrum underutilization by enabling unlicensed users to opportunistically utilize temporally unused licensed spectrums in a cautious manner. In Cognitive Radio Ad Hoc Networks (CRAHNs), data routing is one of the most challenging tasks since the channel availability and node mobility are unpredictable. Moreover, the network performance is severely degraded due to large numbers of path failures. In this paper, we propose the Fault-Tolerant Cognitive Ad-hoc Routing Protocol (FTCARP) to provide fast and efficient route recovery in presence of path failures during data delivery in CRAHNs. The protocol exploits the joint path and spectrum diversity to offer reliable communication and efficient spectrum usage over the networks. In the proposed protocol, a backup path is utilized in case a failure occurs over a primary transmission route. Different cause of a path failure will be handled by different route recovery mechanism. The protocol performance is compared with that of the Dual Diversity Cognitive Ad-hoc Routing Protocol (D2CARP). The simulation results obviously prove that FTCARP outperforms D2CARP in terms of throughput, packet loss, end-to-end delay and jitter in the high path-failure rate CRAHNs.

• Journal of Global Scholars of Marketing Science
• /
• v.18 no.3
• /
• pp.89-114
• /
• 2008

Most of the extant studies on communication effects have been devoted to the typical issue, "what types of communication activities are more effective for brand awareness or brand attitudes?" However, little research has addressed another question on communication decisions, "what makes communication activities less effective?" Our study focuses on factors negatively influenced on the efficiency of communication activities, especially of Advertising. Some studies have introduced concepts closely related to our topic such as consumer confusion, brand confusion, or belief confusion. Studies on product belief confusion have found some factors misleading consumers to misunderstand the physical features of products. Studies on brand confusion have uncovered factors making consumers confused on brand names. Studies on advertising confusion have tested the effects of ad models' employed by many other firms for different products on communication efficiency. We address a new concept, Ad noises, which are any factors interfering with consumers exposed to a particular advertisement in understanding messages provided by advertisements. The objective of this study is to understand the effects of ad noises caused by ad models on brand awareness and brand attitude. There are many different types of AD noises. Particularly, we study the effects of AD noises generated from ad model selection decision. Many companies want to employ celebrities as AD models while the number of celebrities who command a high degree of public and media attention are limited. Inevitably, several firms have been adopting the same celebrities as their AD models for different products. If the same AD model is adopted for TV commercials for different products, consumers exposed to those TV commercials are likely to fail to be aware of the target brand due to interference of TV commercials, for other products, employing the same AD model. This is an ad noise caused by employing ad models who have been exposed to consumers in other advertisements, which is the first type of ad noises studied in this research. Another type of AD noises is related to the decision of AD model replacement for the same product advertising. Firms sometimes launch another TV commercial for the same products. Some firms employ the same AD model for the new TV commercial for the same product and other firms employ new AD models for the new TV commercials for the same product. The typical problem with the replacement of AD models is the possibility of interfering with consumers in understanding messages of the TV commercial due to the dissimilarity of the old and new AD models. We studied the effects of these two types of ad noises, which are the typical factors influencing on the effect of communication: (1) ad noises caused by employing ad models who have been exposed to consumers in other advertisements and (2) ad noises caused by changing ad models with different images for same products. First, we measure the negative influence of AD noises on brand awareness and attitudes, in order to provide the importance of studying AD noises. Furthermore, our study unveiled the mediating conditions(variables) which can increase or decrease the effects of ad noises on brand awareness and attitudes. We study the effects of three mediating variables for ad noises caused by employing ad models who have been exposed to consumers in other advertisements: (1) the fit between product image and AD model image, (2) similarity between AD model images in multiple TV commercials employing the same AD model, and (3) similarity between products of which TV commercial employed the same AD model. We analyze the effects of another three mediating variables for ad noises caused by changing ad models with different images for same products: (1) the fit of old and new AD models for the same product, (2) similarity between AD model images in old and new TV commercials for the same product, and (3) concept similarity between old and new TV commercials for the same product. We summarized the empirical results from a field survey as follows. The employment of ad models who have been used in advertisements for other products has negative effects on both brand awareness and attitudes. our empirical study shows that it is possible to reduce the negative effects of ad models used for other products by choosing ad models whose images are relevant to the images of target products for the advertisement, by requiring ad models of images which are different from those of ad models in other advertisements, or by choosing ad models who have been shown in advertisements for other products which are not similar to the target product. The change of ad models for the same product advertisement can positively influence on brand awareness but positively on brand attitudes. Furthermore, the effects of ad model change can be weakened or strengthened depending on the relevancy of new ad models, the similarity of previous and current ad models, and the consistency of the previous and current ad messages.

• Biomedical Science Letters
• /
• v.23 no.4
• /
• pp.303-309
• /
• 2017

${\beta}$-sitosterol, one of phytosterols, exhibited numerous pharmacological effect including anti-inflammatory, anti-cancer and immune-modulating properties. This study attempted to determine the pharmacological effects of ${\beta}$-sitosterol on atopic dermatitis (AD). We investigated to ascertain the pharmacological effects of ${\beta}$-sitosterol on 2, 4-dinitrochlrobenzene (DNCB)-induced AD symptom and histamine-induced scratching behaviors in mice. Additionally, we evaluated the effects of ${\beta}$-sitosterol on the interleukin (IL)-6 levels in HaCaT cells and skin tissue of AD. The findings of this study demonstrated that ${\beta}$-sitosterol reduced AD clinical symptoms such as eczematous, erythema and dryness and serum histamine and IgE levels in DNCB-induced AD model and histamine-induced scratching behaviors in mice. Additionally, ${\beta}$-sitosterol inhibited the IL-6 expression in AD-like skin lesion and HaCaT cells. Collectively, these findings provide that ${\beta}$-sitosterol could be a therapeutic agent for skin inflammation including AD.

• The Korean Journal of Community Living Science
• /
• v.24 no.3
• /
• pp.369-379
• /
• 2013

The purpose of this study was to investigate the prevalence rate of atopic dermatitis (AD) and indoor risk factors of AD in school-aged children living in Changwon, which is one of the largest industrial cities in Korean. Data were collected from 2,118 children in 12 elementary schools in Changwon city. A cross-sectional questionnaire based on the Korean Version of the ISAAC (International Study of Allergy and Asthma in Childhood) was employed to survey the $1^{st}$ and $4^{th}$ year elementary students from the 12 elementary schools in Changwon. The life time and last 12-month prevalence of itchy eczema were 20.6%; 70.5% in the elementary children. The life time and last 12-month prevalence of AD diagnosis were 28.8%; 12.6% in the elementary children. There was only one elementary school that was abnormal in the levels of particulate matters (PM), and $Co_2$. Multivariate logistic regression analysis revealed that risk factors for AD were BMI, the levels of PM, $Co_2$, CO, $No_2$, $O_3$, Ethylebenzene, and Xylene. This study could be used to manage possible risk factors that are related to the prevalence of AD and develop the strategies for prevention of AD.

• Science of Emotion and Sensibility
• /
• v.16 no.1
• /
• pp.11-28
• /
• 2013

This article aims to explore the interactive roles of types of primed identity (local versus global identity) and types of ad framing on brand evaluations. The authors designed 2 experiments in which each experiment followed a $2{\times}2$ between-subject design. The empirical results showed that a gain-framed ad induced more positive emotional responses than a loss-framed ad, and the positive affective responses lead to more favorable brand evaluation. Furthermore, the results showed that there were interactive effects of primed identity and types of advertisement frame on brand evaluation. In the additional analysis, the results showed that when people with local identity were exposed to the gain-framed ad, they would engage in a higher level of integration processing than those in the control group, which in turn induced more favorable evaluation to the local brand. That is, the integration processing mode played a mediating role between the interaction (local id priming ${\times}$ ad frame) and the local brand evaluation. However, in the case of global brand evaluation, the integration processing mode did not play such a mediating role.

• The KIPS Transactions:PartC
• /
• v.11C no.7 s.96
• /
• pp.905-916
• /
• 2004

Self-organizing hierarchical ad hoc network (SOHAN) is a new ad-hoc network architecture designed to improve the scalability properties of conventional 'flat' ad hoc networks. This network architecture consists of three tiers of ad-hoc nodes, i.e.. access points, forwarding nodes and mobile nodes. This paper presents a topology discovery and routing protocol for the self-organization of SOHAN. We propose a cross-layer path metric based on link quality and MAC delay which plays a key role in producing an optimal cluster-based hierarchical topology with high throughput capacity. The topology discovery protocol provides the basis for routing which takes place in layer 2.5 using MAC addresses. The routing protocol is based on AODV with appropriate modifications to take advantage of the hierarchical topology and interact with the discovery protocol. Simulation results are presented which show the improved performance as well as scalability properties of SOHAN in terms of through-put capacity, end-to-end delay, packet delivery ratio and control overhead.

• Journal of Digital Convergence
• /
• v.17 no.2
• /
• pp.81-89
• /
• 2019

The purpose of this paper was to investigated the effect of the constituents of Facebook advertisement on ad fitness recognition and WOM intension. In addition, we confirmed the mediating effect of ad fitness recognition. For this purpose, data were collected for Facebook 371 users. The research method used factor analysis and covariance structure analysis. The results of this study were as follows: First, the advertising interest characteristics of Facebook ads had a significant effect on ad fitness and word-of-mouth intension. Second, personalized fit informational attributes of Facebook ads had a significant effect on ad fitness and WOM intension. Third, the perceived responsiveness had a significant effect on perceived fitness of advertisement and WOM intention. Fourth, perceived fitness recognition of Facebook advertisement had a significant effect on WOM intension. The results of this study provide consumers with information on what to consider when creating an identity advertisement and effective advertisement as Facebook advertisement.