• Title/Summary/Keyword: mobility performance index

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Shock Response Analysis of 2.5in Hard Disk Drive Supported by Rubber Mounts (고무 마운트로 지지된 2.5인치 하드디스크 드라이브의 충격 응답 해석)

  • seol Woong;Chang Young-Bae;Park No-Cheol;Park Young-Pil
    • 정보저장시스템학회:학술대회논문집
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    • 2005.10a
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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.

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A Method for Generating Malware Countermeasure Samples Based on Pixel Attention Mechanism

  • Xiangyu Ma;Yuntao Zhao;Yongxin Feng;Yutao Hu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.18 no.2
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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.

The Effects of Trunk Control Ability on Balance, Gait, and Functional Performance Ability in Patients With Stroke (뇌졸중 환자의 체간 조절 수준이 균형과 보행 및 기능적 수행 능력에 미치는 영향)

  • An, Seung-Heon;Chung, Yi-Jung;Park, Sei-Yeon
    • Physical Therapy Korea
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    • v.17 no.2
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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.

Effects of Music-based Sling Exercise Program on Cognition, Walking, and Functional Mobility in Elderly with Dementia: Single-blinded, Randomized Controlled Trial (음악 기반 슬링운동 프로그램이 치매환자의 인지, 보행 및 기능적 운동성에 미치는 효과)

  • Park, Hyun-Ju;Kang, Tae-Woo;Oh, Duck-Won
    • Journal of the Korean Society of Physical Medicine
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    • v.14 no.4
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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.

A Performance Evaluation of EAP-TLS Authentication Model in the AAAv6 (AAAv6에서의 EAP-TLS 인증모델 성능평가)

  • Jeong, Yun-Su;Kim, Hyung-Do;Lee, Hae-Dong;Kim, Hyun-Gon;Lee, Sang-Ho
    • The KIPS Transactions:PartC
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    • v.11C no.3
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    • pp.309-318
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    • 2004
  • AAAv6-based Diameter method is using in the user authentication to satisfy the users' increasing user authentication demand and to supply a safe communication between mobile node and server in the Mobile IP. therefore, In this paper, We design a model of server capacity based on EAP-TLS that in one of AAAv6 models with mobility among domains to get the optimized capacity index of the server for user authentication accomplishment. We elicitat the authentication capacity index for each server of which is accomplishing in user authentication using DSA/RSA algorithm and purpose the optimized condition for the AAAv6 capacity by the index.

Performance Analysis of D2D system Considering users' locations under the Overlay Convergent Networks of Cognitive Networking (인지기반 중첩 융합 네트워크에서 위치정보에 기반한 D2D 시스템의 성능분석)

  • Kim, Jeong-Ho
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.10
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    • pp.3-10
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    • 2014
  • In this paper, the performances of the presented D2D (device-to-device) systems under the environment of the cognitive convergent overlay networks are evaluated based upon the locations of the D2D users' terminals, the power consumptions of the terminals and the reductions of the interference levels. As the capabilities of the users' terminals improve, the optimization of the system is crucial to the efficient utilization of the radio resources of the individual networks considering their mobility and the features of their networks. Users' mobility model is given for the performance evaluation of the D2D system. In this paper, the performances of the D2D systems are evaluated in terms of the performance index of the FER (frame error rate) employing multiantenna techniques (MIMO:multiple input multiple output) for the various network environments.

Authentication Processing Optimization Model for the EAP-MD5 AAAv6 Operation (EAP-MD5 AAAv6 운영을 위한 인증처리 최적화 모델)

  • Jeong, Yoon-Su;Woo, Sung-Hee;Lee, Sang-Ho
    • The KIPS Transactions:PartC
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    • v.12C no.5 s.101
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    • pp.757-764
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    • 2005
  • With the increasing service Qualify and security in the Mobile Internet Diameter technology based on the AAAv6 is being used in the user authentication. But there are some Problems on the authentication Procedures of the Diameter in which the security falls down from a loaming service or Internet transmission course. We combine it with the cipher algorithm like EAP-MD5 and accomplish a user authentication processing. If we want to supply the user authentication with the mobility among domains by AAAv6-based Diameter, we need the efficient capacity allocation among AAA attendent, AAAv, AhAb, AAAh, HA servers in the AAAv6. Therefore in this paper, we propose to make the authentication capacity index to carry out user authentication ability by analyzing an EAP-MD5S server capacity model of AAAv6 authentication models for users with mobility among domains, and to find the optimized condition for the AAAv6 capacity by the index.

A Study on Korea's Trade Performance in Spain and its Strategies for Entry into Spanish Market (한국의 대(對)스페인 교역성과와 시장진출 전략에 관한 연구)

  • Soo-Suk Sohn
    • Korea Trade Review
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    • v.46 no.1
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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.

A Systematic Review of the Effects of Robotic-Assisted Training on Gait Performance in Persons with Subacute Hemiparetic Stroke (아급성 편마비 뇌졸중 환자의 보행에 로봇-보조훈련이 미치는 영향에 관한 체계적 고찰)

  • Se-in Park;Su-jin Hwang
    • PNF and Movement
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    • v.21 no.1
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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.

The Relative·Absolute Reliability and Validity of Step Test in Patients with Chronic Stroke (만성 뇌졸중 환자들의 Step Test의 상대적·절대적 신뢰도와 타당도)

  • Lee, Byoungkwon;Choi, Hyunsoo;An, Seungheon
    • Journal of The Korean Society of Integrative Medicine
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    • v.5 no.1
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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.