• 정보저장시스템학회:학술대회논문집
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• 정보저장시스템학회 2005년도 추계학술대회 논문집
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• pp.215-216
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• 2005

Nowadays, mobility as well as basic performances has been the important performance index of hard disk drive, It makes a system unstable to satisfy mobility, huge storage capacity and high transfer rate. Shock and vibration analysis has been important because hard disk drive could be exposed by external shock and vibration. The probability of this situation has been increasing. In this research, each component and the whole system of 2.5in HDD are made to a finite element model. Results of finite element analysis are compared with the results of experimental modal analysis. Shock analysis is executed for 2.5in hard disk drive.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제18권2호
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• pp.456-477
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• 2024

With information technology's rapid development, the Internet faces serious security problems. Studies have shown that malware has become a primary means of attacking the Internet. Therefore, adversarial samples have become a vital breakthrough point for studying malware. By studying adversarial samples, we can gain insights into the behavior and characteristics of malware, evaluate the performance of existing detectors in the face of deceptive samples, and help to discover vulnerabilities and improve detection methods for better performance. However, existing adversarial sample generation methods still need help regarding escape effectiveness and mobility. For instance, researchers have attempted to incorporate perturbation methods like Fast Gradient Sign Method (FGSM), Projected Gradient Descent (PGD), and others into adversarial samples to obfuscate detectors. However, these methods are only effective in specific environments and yield limited evasion effectiveness. To solve the above problems, this paper proposes a malware adversarial sample generation method (PixGAN) based on the pixel attention mechanism, which aims to improve adversarial samples' escape effect and mobility. The method transforms malware into grey-scale images and introduces the pixel attention mechanism in the Deep Convolution Generative Adversarial Networks (DCGAN) model to weigh the critical pixels in the grey-scale map, which improves the modeling ability of the generator and discriminator, thus enhancing the escape effect and mobility of the adversarial samples. The escape rate (ASR) is used as an evaluation index of the quality of the adversarial samples. The experimental results show that the adversarial samples generated by PixGAN achieve escape rates of 97%, 94%, 35%, 39%, and 43% on the Random Forest (RF), Support Vector Machine (SVM), Convolutional Neural Network (CNN), Convolutional Neural Network and Recurrent Neural Network (CNN_RNN), and Convolutional Neural Network and Long Short Term Memory (CNN_LSTM) algorithmic detectors, respectively.

• 한국전문물리치료학회지
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• 제17권2호
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• pp.33-42
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• 2010

The aim of this study was to investigate correlations of the Trunk Control Test (TCT), Postural Assessment Scale for Stroke (PASS-TC), and Trunk Impairment Scale (TIS) and to compare the TCT, PASS-TC, TIS and its subscales in relation to balance, gait and functional performance ability after stroke. Sixty-two stroke patients attending a rehabilitation program participated in the study. Trunk control was measured with the use of TCT, PASS-TC, TIS balance (Berg Balance scale; BSS), gait ability (10 m walk test), functional performance ability (Tuned Up and Go Test TUG) and the mobility part of the Modified Barthel index (MBI), Fugl Meyer-Upper/Lower Extremity ($FM-U{\cdot}L/E$), The scatter-plot (correlation coefficient) was composed for the total scores of the TCT, PASS-TC, and TIS. The multiple regression analysis was performed to evaluate the impact of trunk control on balance, gait, and functional performance ability. Twenty eight participants (45.2%) and twenty participants (32.3%) obtained the maximum score on the TCT and PASS-TC respectively; no subject reached the maximum score on the Trunk Impairment Scale. There were significant correlations between the TIS and TCT (r=.38, p<.01), PASS-TC (r=.30, p<.05), TCT and PASS-TC (r=.59, p<.01). Stepwise multiple regression analysis showed that the BBS score (${\beta}=.420{\sim}.832$) had slightly more power in predicting trunk control than the $FM-U{\cdot}L/E$. TIS-dynamic sitting balance, TUG and the MBI-mobility part. This study 치early indicates that trunk control is still impaired in stroke patients. Measures of trunk control were significantly related with values of balance, gait and functional performance ability. The results imply that management of trunk rehabilitation after stroke should be emphasized.

• 대한물리의학회지
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• 제14권4호
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• pp.143-152
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• 2019

PURPOSE: This examined the effects of a sling exercise based on music on the cognition, physical performance of patients with dementia. METHODS: Thirty subjects with dementia volunteered to participate in this study. All subjects were allocated randomly to either the experimental group or control group, with 15 subjects in each group. All subjects underwent the exercise program for an average of 60 minutes per day for 16 weeks. The experimental group performed sling exercise based on music, and the control group performed the general exercise program. Assessments were made using the Korean version of mini-mental state examination (MMSE-K), 10 m walk test (10MWT), Tinetti mobility test (TMT), and Katz's Index of Independence in activity daily living (KIIADL) to detect changes in the cognitive level and physical performance before and after the 16-week training period. A paired t-test was conducted to compare the within-group change before and after the intervention. An independent t-test was performed to compare the between-group difference. The statistical significance level was set to α=.05 for all variables. RESULTS: The experimental group showed significant within-group changes in the MMSE-K, 10MWT, TMT, and KIIADL (p<.05). The control group showed a significant change in only the KIIADL (p<.05). A significant difference was observed between the experimental group and the control group regarding the change in MMSE-K and KIIADL after the interventions (p<.05). CONCLUSION: A music-based sling exercise program effectively improves cognition, physical performance, and ADL in patients with dementia. Further studies with a wider range of subjects and scientific equipment will be needed to strengthen the results of this study.

• 정보처리학회논문지C
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• 제11C권3호
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• pp.309-318
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• 2004

Mobile IP에서 이동노드와 서버간의 안전한 통신을 제공하고 급증하는 사용자 인증 서비스 요구를 만족시키기 위해 AAAv6기반 다이어미터(Diameter) 기술이 사용자 인증에 사용되고 있다. 따라서 이 논문에서는 사용자 인증기능 수행을 위한 서버들의 최적 성능 지표를 구하고자 도메인간의 이동성을 가지는 AAAv6 인증 모델중의 하나인 EAF-TLS기반의 서버 성능 평가 모델을 설계한다. 그리고 DSA/RSA암호 알고리즘을 이용하여 사용자 인증 기능을 수행하는 각 서버의 최적 성능지표를 도출하여 AAAv6의 운영을 최적화 시킬 수 있는 환경을 제시한다.

• 전자공학회논문지
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• 제51권10호
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• pp.3-10
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• 2014

본 논문에서는 인지 기반 중첩 융합 네트워크 환경 하에서의 사용자의 위치정보를 토대로 사용자 단말기의 전력소모감소와 간섭신호의 저감효과를 극대화하기 위한 기본적인 D2D(device-to-device)시스템을 제시하고 무선 전송 환경에서의 시스템 성능을 분석하고자 한다. 단말기의 기능성이 좋아짐에 따라 스마트한 지능을 기반으로 자원의 효과적 활용에 적합한 개별 이종 네트워크의 특성분석과 특성을 반영하는 시스템 측면의 최적화가 중요하다고 할 수 있다. 본 논문에서는 사용자 이동특성에 기반하여 인접 단말기와의 직접 통신하는 절차를 구성하여 단말기 간 직접 통신에 다중안테나 기술을 적용할 경우 이에 따른 FER(frame error rate) 등의 성능특성을 살펴보고자 한다.

• 정보처리학회논문지C
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• 제12C권5호
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• pp.757-764
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• 2005

이동 인터넷 환경에서 보안성과 급증하는 서비스 요구를 효율적으로 제어하기 위해 AAAv6기반 Diameter 기술이 사용자 인증에 사용되고 있다. 그러나 Diameter에서 제공하는 기본적인 인증기법은 로밍 서비스나 인터넷 전송 과정에서 보안성이 떨어지는 단점을 가지고 있어 EAP-MD5와 같은 암호알고리즘과 결합하여 사용자 인증처리를 수행한다. 이러한 사용자 인증처리를 효율적으로 수행하기 위해서는 AAAv6 환경을 구성하고 있는 AAA attendent, AAAv, AAAb, AAAh, HA 서버들의 성능 충족 방안이 필요하다. 따라서, 이 논문에서는 도메인간의 이동성을 가지는 AAAv6 인증 모델중의 하나인 EAP-MD5기반의 운영 모델을 설계하고 실험을 통하여 사용자 인증 기능을 수행하는 각 서버의 최적 성능지표를 산출하고 이를 이용하여 AAAv6의 사용자 인증 처리를 최적화 시킬 수 있는 지표들을 제시한다.

• 무역학회지
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• 제46권1호
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• pp.59-81
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• 2021

This paper aims to analyze Korea's trade and investment performance in Spain and the business environment of Spain, and to find efficient strategies for entering into the Spanish market. This study is organized into five chapters. To begin with, it explains an overview of the Spanish economy and the current status of its major industries. Then, it analyzes Korea's trade and investment performance in Spain, the structure of comparative advantage and the trade trends of major import and export items, since 2011 when the Korea-EU FTA went into effect. Lastly, based on the results of this analysis, Korea's strategies for entering into the Spanish market are derived. The strategies derived from the analysis are as follows: (1) entering startups in the Spanish market through CVC cooperation and participation in large tech forums, (2) linking the Spanish interest in K-Culture to consumer goods exports, (3) promoting cooperation in the IT industry in response to the Spanish government's 'Connected Industry 4.0', (4) building a new Korean-Spanish value chain in response to the mobility revolution, (5) advancing jointly into a third country by combining the strengths of both Korea and Spain, (6) cooperating with the Spanish government to establish a sustainable energy policy, (7) promoting jointly with the Spanish government through smart city strategies and project exchanges, and (8) building a European logistics hub in Spain in preparation for post-Brexit.

• PNF and Movement
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• 제21권1호
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• pp.1-10
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• 2023

Purpose: This systematic review aims to determine whether robot-assisted training is more effective in gait training for persons with subacute hemiparetic stroke. Methods: This study adopted a systematic review study design focused on subacute hemiparetic stroke, and four core academic databases were searched until June 11, 2021, for relevant studies, including PubMed, Embase, the Cochrane Library, and ProQuest Central. The review included randomized controlled trials (RCTs) evaluating the effects of robotic-assisted training on gait performance in persons with a diagnosis of subacute hemiparetic stroke. The selected RCT studies were qualitatively synthesized based on the population, intervention, comparison, outcome, settings, and study design (PICOS-SD). Results: The study selected five RCTs involving 253 subacute hemiparetic stroke patients and performing robotic-assisted gait training using the following devices: the Lokomat, Morning Walk, Walkbot, ProStep Plus, or Gait Trainer II. Five RCTs were eligible for the meta-analysis after quantitative synthesis, and the results showed that the robot-assisted gait training group had a greater gait performance than the control group based on the 10-meter walk test, Berg balance scale, Rivermed mobility index, functional ambulation category, and modified Barthel index. Conclusion: The results of this study showed that the gait performance of subacute hemiparetic stroke patients changes throughout robot-assisted gait training, but there were no indications that any of the clinically relevant effects of robot-assisted training are greater than those of conventional gait training. Further, the small sample size and different therapeutic intensities indicate that definitive conclusions could not be made.

• 대한통합의학회지
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• 제5권1호
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• pp.43-53
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• 2017

Purpose : To examine the relative absolute reliability and validity of step test (ST) scores in subjects with chronic stroke. Method : A total of 27 stroke patients, participated in the study. A relative reliability index (intraclass correlation coefficient, ICC) was used to examine the level of agreement of inter-rater test-retest reliability for ST score. Absolute reliability indices, including the standard error of measurement(SEM) and the minimal detectable change (MDC), and limits of agreement by Bland and Altman analysis. The validity was demonstrated by spearman correlation of ST score with 10 m Walk Test (10mWT), Fugl-Meyer Assessment-Lower/Extremity (FMA-L/E)-total score, Berg Balance Scale (BBS)-total score. Result : An excellent inter-rater reliability in ST scores was found (paretic, ICC=0.993~0.996; nonparetic, ICC=0.982~0.991). In addition, excellent test-retest reliability was found (paretic, ICC=0.992; nonparetic, ICC=0.967). It all showed acceptable SEM of the ST score as paretic and nonparetic were 0.22 and 0.46 respectively (average score <10 %), and the MDC of the paretic and nonparetic were 0.61 and 1.27 respectively (possible highest score <20 %). indicating that measures had a small and acceptable measurement error. The ST score of paretic and nonparetic were also found to be significantly associated with 10MWT (r=0.77~0.79), FMA-LE scores (r=0.73~0.81) and BBS scores (r=0.72~0.76). Conclusion : The ST showed highly sufficient Inter-rater test-retest agreement and validity and acceptable measurement errors caused by due to chance variation in measurement. It also can be used by clinicians and researchers to assess the balance and mobility performance and monitor functional change in chronic stroke patients.