• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.1
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• pp.21-40
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• 2018

In this paper, we propose the distributed robust beamforming design scheme in cognitive two-way amplify-and-forward (AF) relay networks with imperfect channel state information (CSI). Assuming the CSI errors follow a complex Gaussian distribution, the objective of this paper is to design the robust beamformer which minimizes the total transmit power of the collaborative relays. This design will guarantee the outage probability of signal-to-interference-plus-noise ratio (SINR) beyond a target level at each secondary user (SU), and satisfies the outage probability of interference generated on the primary user (PU) above the predetermined maximum tolerable interference power. Due to the multiple CSI uncertainties in the two-way transmission, the probabilistic constrained optimization problem is intractable and difficult to obtain a closed-form solution. To deal with this, we reformulate the problem to the standard form through a series of matrix transformations. We then accomplish the problem by using the probabilistic approach based on two sorts of Bernstein-type inequalities and the worst-case approach based on S-Procedure. The simulation results indicate that the robust beamforming designs based on the probabilistic method and the worst-case method are both robust to the CSI errors. Meanwhile, the probabilistic method can provide higher feasibility rate and consumes less power.

• The Research Journal of the Costume Culture
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• v.25 no.5
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• pp.543-560
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• 2017

The aim of this paper is to find which types of pop-up store positively influence consumers and to analyze the factors that affect brand attitude and behavioral intention across different fashion pop-up store formats. The data was collected from 217 respondents in their 20s and 30s and then subjected to descriptive statistical analysis, oneway ANOVA and regression analysis using SPSS Statistics. The results of the oneway ANOVA test indicated that the 'Pop-up store of alliance with different kinds of industries' is the most effective type for increasing brand preference and brand recognition amongst consumers. Some further insights can be made from the regression analysis results. There are differences between pop-up store formats in terms of the cognitive factors influencing brand attitude and behavioral intention. Moreover, there are differences between pop-up store formats in terms of brand attitude factors influencing behavioral intention. Through the results of this study, fashion companies can determine the best type of pop-up store to open depending on their aims. In conclusion, this study provides valuable insights to fashion marketers, helping them to determine the appropriate factors to consider when planning fashion pop-up stores. Academically, this paper contributes to expanding the range of research on fashion pop-up retail by studying consumer experiences of different pop-up store types.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.7
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• pp.1422-1428
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• 2009

In this paper, we consider an independent type cognitive radio system where secondary users can utilize empty channels that are not currently used by primary users having the license to these channels. In the previous works, secondary users search channels sequently or randomly to detect activities of primary user on channels. These channel searching methods however are not suitable to the characteristics of the wireless environment. Therefore, we propose a channel searching method based on the channel list for the purpose of reducing the channel searching time and improving the throughput of secondary users. In the proposed method, we firstly determine weighting value of each channel based on the history of channel activities of primary users and add the weighing value to current channel state buffer. And then, we search an empty channel from channel with smallest value to one with the biggest value. Finally, we compare the performances of the proposed method with those of the sequential channel searching and the random channel searching methods in terms of average channel searching time and average number of transmissions of secondary user.

• Physical Therapy Rehabilitation Science
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• v.7 no.3
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• pp.139-145
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• 2018

Objective: Older persons with diabetes mellitus (DM) are particularly more likely to have fallen in the previous year than those without DM. The purpose of this study was to investigate the relationship between the risk of falls and type 2 DM in older adults who are 65 years of age or above. Design: A systematic review. Methods: PubMed and other two databases were searched up to August 2, 2018. Observational and cohort studies evaluating fall risk in people who are 65 years of age or above with DM were included. This review extracted the following information from each study selected: first author's surname, year of publication, country, average follow-up period, sex, age at enrollment, study population, measurement variables, relative risk, 95% confidence intervals and controlled variables. Results: This review involved nine cohort studies with 3,765 older adults with DM and 12,989 older adults without DM. Six studies compared with or without DM and two studies compared fallers with non-fallers with DM. Risk factors for falls included impaired cognitive function, diabetes-related complications (peripheral nerve dysfunction, visual impairment), and physical function (balance, gait velocity, muscle strength, and severity of physical activities). Conclusions: People who are 65 years of age or above with DM have increased risk of falling caused by impaired cognitive function, peripheral nerve dysfunction, visual impairment, and physical function in community-dwellers. For adults who are 65 years of age or older with DM, research fields and clinical settings should consider therapeutic approaches to improve these risk factors for falls.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.9_10 s.157
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• pp.1455-1463
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• 2006

The purpose of this study was to examine the advertisement effects of mobile fashion advertisements, specifically focusing on how the mobile fashion advertisement effects work according to advertisement types and categories. Two hundred female college students participated in this study. For data analysis, descriptive statistics, factor analysis, and t-test were used for this study. As the results, first, advertisement attitudes were classed into three factors such as cognitive factor emotional factor, and behavioral factor. Second, regarding the effect of advertisement types, pull advertisement type had higher advertisement attitudes, and higher purchasing intention than push advertisement type. There was not significant in brand attitudes between pull advertisement and push advertisement. Third, for the effects of advertisement categories, clothing advertisement had higher cognitive factor and behavioral factor, and higher purchasing intention than accessory advertisement. There were not significant in emotional factor and brand attitude between clothing and accessory advertisements. Based on these results, M-commerce fashion advertisement marketing strategies would be suggested.

• Korean Journal of Cognitive Science
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• v.17 no.4
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• pp.271-286
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• 2006

In this paper, we introduce automatic question generation technique using the language resources like User-Word Intelligent Network(U-WIN) and Korean dictionary including quite a for of information. And we present Korean word learning system with this technique. The item pool method which almost learning-system are using makes some problems. As a solution of the problems, we classified into 8 question type and implemented the Korean word learning system which is making the Korean question automatically by using the morphological and semantic information according to the automatic question generation pattern of each type.

• Korean Journal of Cognitive Science
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• v.9 no.1
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• pp.41-46
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• 1998

The argument-structure distributions of predicates in the speech of two roca-type aphasic patients and one Conduction-type patient are compared with both matched controls and each other on the basis of narrative production data. Whereas English-speaking agrammatics have been reported to have difficulties producing noncopular unaccusative predicates (Kegl 1995) Korean-speaking agrammatics are found not to have particular difficulties with unaccusative predicates. On the assumption that agrammatics lack specific syntactic knowledge for the processing of displaced arguments from their lexically specified positions. it is proposed that unaccusatives in Korean do not involve the displacement of arguments for Case-theoretic reasons or involve a vacuous movement. if any.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2000.05a
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• pp.108-113
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• 2000

자동사의 두 하위부류, 비대격(unaccusative) 동사와 비능격 (unergative)동사는 Perlmutter(1978)의 비대격 가설 (Unaccusative Hypothesis) 이후 여러 관점에서 활발히 노의 되어왔다. 한국어에서는 사건구조적 측면에서 두 부류가 차이를 보이며, 이런 사실은 인간의 인지작용과 밀접한 관련을 맺는다. 사건구조를 과정(process)사건과 상태(state)로 가정할 때 비능격 동사는 과정사건이, 비대격 동사는 상태사건이 부각된다. 비대격 동사도 두 가지 부류로 나뉠 수 있는데, '도착하다'처럼 과정사건이 언어표현에서 중시되지 않고 결과적인 상태부분만 중요시 되는 유형(unacc_type_1)과 '녹다'처럼 과정사건도 중시되는 사건 구조를 지닌 유형(unacc_type_2)이다. 결국 비대격 동사는 결과상태를 중시하는 사건구조를 중요시 하지만 과정사건의 지각 정도에 따라 다른 양상을 보인다. 한편 비대격 동사는 사동사와도 밀접한 연관 관계를 지닌다. 많은 논의에서 비대격/사동의 교체를 논리적 다의어로 보고 분석을 시도해 왔다. 따라서 사동사를 중심으로 분석한 경우와 비대격 동사를 중심으로 분석한 경우가 있다. 본고에서는 사동분석(causative analysis)은 한국어 기술에는 적절치 않다고 판단한다. 사동분석에서 도입하는 행동주의 사건유발부분이 반드시 비대격 동사의 표현에 필수적인 것은 아니기 때문이다. 끝으로 Pustejovsky(1995)의 생성어휘부(Generative Lexicon) 이론을 한국어에 맞게 확장·수정한 이정민·강범모·남승호(1997)의 모형에 따라 두 가지 유형의 비대격 동사의 어휘 의미구조를 표상한다.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2000.05a
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• pp.76-86
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• 2000

Conventional atom model must be criticized on the following four points. (1) Natural motions between positive and negative entities are not circular motions but linear going and returning ones, for examples sexual motion, tidal motion, day and night etc. (2) Potential energy generation was neglected when electron changes its orbit from outer one to inner one. The hv is the kinetic energy of the photo-electron. The total energy difference between orbits comprises kinetic and potential energies. (3) The structure of the space must be taken into consideration because the properties of the electron do not change during the transition from outer orbit to inner one even though it produces photon. (4) Total energy conservation law applies to the energy flow between mind and matter because we daily experiences a interconnection between mind and body. $\prod$-rays come out from the crystallizing $\pi$-bondings when they vibrate or deform. Gaston Naessens(1950) invented a microscope, which can visualize the $\pi$-rays in blood. Unordinarily agglomerated spores of $\pi$-rays may provoke poor immunity and bad illness. The agglomerated spores of $\pi$-rays can make closed type $\pi$-bondings in the case of carbohydrates and esters but proteins build open type $\pi$-bondings because the peptide bonds are planar, which principle produces a life.

• Korean Journal of Cognitive Science
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• v.11 no.3_4
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• pp.73-81
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• 2000

This study was conducted to investigate some characteristics of representation of category knowledge and script knowledge. Using primed lexical decision task with higher level primers in the representation structure, Experiment 1 examined the interaction effects between knowledge type and concept typicality. It was found that the concept typicality has some effects in category representation, while it has no significant effect in script representation. In Experiment 2, primers of the lower hierarchy in the representation structure were employed. The results showed that the main effect of knowledge type was significant: the response time for category knowledge was faster than that for script knowledge. Typicality effect did not show in this experiment. The results of t the two experiments suggest that category knowledge is represented in hierarchy and typicality. while script knowledge may lack in that characteristics. Other aspects of the differences in characteristics of category- and script- knowledge representation were discussed,