• Title/Summary/Keyword: Mean vector

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Analysis of the Lower Extremity's Coupling Angles During Forward and Backward Running (앞으로 달리기와 뒤로 달리기 시 하지 커플링각 분석)

  • Ryu, Ji-Seon
    • Korean Journal of Applied Biomechanics
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    • v.16 no.3
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    • pp.149-163
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    • 2006
  • The purpose of this study was to compare the lower extremity's joint and segment coupling patterns between forward and backward running in subjects who were twelve healthy males. Three-dimensional kinematic data were collected with Qualisys system while subjects ran to forward and backward. The thigh internal/external rotation and tibia internal/external rotation, thigh flexion/extension and tibia flexion/extension, tibia internal/external rotation and foot inversion/eversion, knee internal/external rotation and ankle inversion/eversion, knee flexion/extension and ankle inversion/eversion, knee flexion/extension and ankle flexion/extension, and knee flexion/extension and tibia internal/external rotation coupling patterns were determined using a vector coding technique. The comparison for each coupling between forward and backward running were conducted using a dependent, two-tailed t-test at a significant level of .05 for the mean of each of five stride regions, midstance(1l-30%), toe-off(31-50%), swing acceleration(51-70%), swing deceleration(71-90), and heel-strike(91-10%), respectively. 1. The knee flexion/extension and ankle flexion/extension coupling pattern of both foreward and backward running over the stride was converged on a complete coordination. However, the ankle flexion/extension to knee flexion/extension was relatively greater at heel-strike in backward running compared with forward running. At the swing deceleration, backward running was dominantly led by the ankle flexion/extension, but forward running done by the knee flexion/extension. 2. The knee flexion/extension and ankle inversion/eversion coupling pattern for both running was also converged on a complete coordination. At the mid-stance. the ankle movement in the frontal plane was large during forward running, but the knee movement in the sagital plane was large during backward running and vice versa at the swing deceleration. 3. The knee flexion/extension and tibia internal/external rotation coupling while forward and backward run was also centered on the angle of 45 degrees, which indicate a complete coordination. However, tibia internal/external rotation dominated the knee flexion/extension at heel strike phase in forward running and vice versa in backward running. It was diametrically opposed to the swing deceleration for each running. 4. Both running was governed by the ankle movement in the frontal plane across the stride cycle within the knee internal/external rotation and tibia internal/external rotation. The knee internal/external rotation of backward running was greater than that of forward running at the swing deceleration. 5. The tibia internal/external rotation in coupling between the tibia internal/external rotation and foot inversion/eversion was relatively great compared with the foot inversion/eversion over a stride for both running. At heel strike, the tibia internal/external rotation of backward running was shown greater than that of forward(p<.05). 6. The thigh internal/external rotation took the lead for both running in the thigh internal/external rotation and tibia internal/external rotation coupling. In comparison of phase, the thigh internal/external rotation movement at the swing acceleration phase in backward running worked greater in comparison with forward running(p<.05). However, it was greater at the swing deceleration in forward running(p<.05). 7. With the exception of the swing deceleration phase in forward running, the tibia flexion/extension surpassed the thigh flexion/extension across the stride cycle in both running. Analysis of the specific stride phases revealed the forward running had greater tibia flexion/extension movement at the heel strike than backward running(p<.05). In addition, the thigh flexion/extension and tibia flexion/extension coupling displayed almost coordination at the heel strike phase in backward running. On the other hand the thigh flexion/extension of forward running at the swing deceleration phase was greater than the tibia flexion/extension, but it was opposite from backward running. In summary, coupling which were the knee flexion/extension and ankle flexion/extension, the knee flexion/extension and ankle inversion/eversion, the knee internal/external rotation and ankle inversion/eversion, the tibia internal/external rotation and foot inversion/eversion, the thigh internal/external rotation and tibia internal/external rotation, and the thigh flexion/extension and tibia flexion/extension patterns were most similar across the strike cycle in both running, but it showed that coupling patterns in the specific stride phases were different from average point of view between two running types.

Effect of Immune System on Retrovirus-Mediated Herpes Simplex Virus Thymidine Kinase Gene Therapy (면역체계가 Retroviral Vector로 이입한 Herpes Simplex Virus Thymidine Kinase 유전자치료에 미치는 영향)

  • Park, Jae-Yong;Joo, So-Young;Chang, Hee-Jin;Son, Ji-Woong;Kim, Kwan-Young;Kim, Keong-Seok;Kim, Chang-Ho;Park, Jae-Ho;Lee, Jong-Ki;Jung, Tae-Hoon
    • Tuberculosis and Respiratory Diseases
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    • v.46 no.2
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    • pp.229-240
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    • 1999
  • Background: The impact of the immune response on cancer gene therapy using viral vectors to deliver a "suicide gene" is currently unclear. A vigrous immune response targeted at viral proteins or transgene may enhance the efficacy of tumor destruction and even augment responses to tumor antigens. These responses may involve the release of cytokines and stimulation of tumor specific cytotoxic T-lymphocytes that enhance therapeutic efficacy. On the other hand, a vigorous rapid cellular immune response may destroy cells expressing the therapeutic gene and attenuate the response to therapy. Furthermore, development of neutralizing antibody responses may prevent readministration of virus, a potentially significant limitation. Evaluating the significance of these limitations in animal models and developing solutions are therefore of obvious importance. Methods: After retroviral transduction of mouse mesothelioma cell line(AB12) with Herpes Simplex Virus thymidine kinase (HSVtk) gene in vitro, subcutaneous flank tumors were established. To study the effect of intact immune system on efficacy of tumor erradication, the ability of the HSVtk/ganciclovir system to inhibit tumor growth was compared among normal Balb/c mice, immunodeficient Balb/c-nude and SCID mice, and Balb/c mice immunosuppressed with cyclosporin. Results: Ganciclovir treatment resulted in greater inhibition of tumor growth in Balb/c mice compared with immunodeficient Balb/c-nude mice and SCID mice(in immunodeficient mice, there were no growth inhibition by ganciclovir treatment). Ganciclovir treatment resulted in greater inhibition of tumor growth in noncyclosporin (CSA) treated Balb/c mice compared with CSA treated Balb/c mice. On day 8, mean ganciclovir-treated tumor volume were 65% of control tumor volume in Balb/c mice versus 77% control tumor volume in CSA-treated Balb/c mice. This effect was still evident during therapy (day 11 and 13). On day 13, non-CSA treated tumor volume was 35% of control tumor volume versus 60% of control tumor volume in CSA treated Balb/c mice. Duration of expression of HSVtk was not affected by the immunosuppression with CSA. Conclusion: These results indicate that the immune responses against retrovirally transduced cells enhance the efficacy of the HSVtk/ganciclovir system. These findings have important implications for clinical trials using currently available retrovirus vectors as well as for future vector design.

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Development and Analysis of COMS AMV Target Tracking Algorithm using Gaussian Cluster Analysis (가우시안 군집분석을 이용한 천리안 위성의 대기운동벡터 표적추적 알고리듬 개발 및 분석)

  • Oh, Yurim;Kim, Jae Hwan;Park, Hyungmin;Baek, Kanghyun
    • Korean Journal of Remote Sensing
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    • v.31 no.6
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    • pp.531-548
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    • 2015
  • Atmospheric Motion Vector (AMV) from satellite images have shown Slow Speed Bias (SSB) in comparison with rawinsonde. The causes of SSB are originated from tracking, selection, and height assignment error, which is known to be the leading error. However, recent works have shown that height assignment error cannot be fully explained the cause of SSB. This paper attempts a new approach to examine the possibility of SSB reduction of COMS AMV by using a new target tracking algorithm. Tracking error can be caused by averaging of various wind patterns within a target and changing of cloud shape in searching process over time. To overcome this problem, Gaussian Mixture Model (GMM) has been adopted to extract the coldest cluster as target since the shape of such target is less subject to transformation. Then, an image filtering scheme is applied to weigh more on the selected coldest pixels than the other, which makes it easy to track the target. When AMV derived from our algorithm with sum of squared distance method and current COMS are compared with rawindsonde, our products show noticeable improvement over COMS products in mean wind speed by an increase of $2.7ms^{-1}$ and SSB reduction by 29%. However, the statistics regarding the bias show negative impact for mid/low level with our algorithm, and the number of vectors are reduced by 40% relative to COMS. Therefore, further study is required to improve accuracy for mid/low level winds and increase the number of AMV vectors.

Accuracy of HF radar-derived surface current data in the coastal waters off the Keum River estuary (금강하구 연안역에서 HF radar로 측정한 유속의 정확도)

  • Lee, S.H.;Moon, H.B.;Baek, H.Y.;Kim, C.S.;Son, Y.T.;Kwon, H.K.;Choi, B.J.
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.13 no.1
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    • pp.42-55
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    • 2008
  • To evaluate the accuracy of currents measured by HF radar in the coastal sea off Keum River estuary, we compared the facing radial vectors of two HF radars, and HF radar-derived currents with in-situ measurement currents. Principal component analysis was used to extract regression line and RMS deviation in the comparison. When two facing radar's radial vectors at the mid-point of baseline are compared, RMS deviation is 4.4 cm/s in winter and 5.4 cm/s in summer. When GDOP(Geometric Dilution of Precision) effect is corrected from the RMS deviations that is analyzed from the comparison between HF radar-derived and current-metermeasured currents, the error of velocity combined by HF radar-derived current is less than 5.1 cm/s in the stations having moderate GDOP values. These two results obtained from different method suggest that the lower limit of HF radar-derived current's accuracy is 5.4 cm/s in our study area. As mentioned in previous researches, RMS deviations become large in the stations located near the islands and increase as a function of mean distance from the radar site due to decrease of signal-to-noise level and the intersect angle of radial vectors. We found that an uncertain error bound of HF radar-derived current can be produced from the separation process of RMS deviations using GDOP value if GDOP value for each component is very close and RMS deviations obtained from current component comparison are also close. When the current measured in the stations having moderate GDOP values is separated into tidal and subtidal current, characteristics of tidal current ellipses analyzed from HF radar-derived current show a good agreement with those from current-meter-measured current, and time variation of subtidal current showed a response reflecting physical process driven by wind and density field.

Mapping Man-Made Levee Line Using LiDAR Data and Aerial Orthoimage (라이다 데이터와 항공 정사영상을 활용한 인공 제방선 지도화)

  • Choung, Yun-Jae;Park, Hyen-Cheol;Chung, Youn-In;Jo, Myung-Hee
    • Journal of the Korean Association of Geographic Information Studies
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    • v.14 no.1
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    • pp.84-93
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    • 2011
  • Levee line mapping is critical to the protection of environments in river zones, the prevention of river flood and the development of river zones. Use of the remote sensing data such as LiDAR and aerial orthoimage is efficient for river mapping due to their accessibility and higher accuracy in horizontal and vertical direction. Airborne laser scanning (LiDAR) has been used for river zone mapping due to its ability to penetrate shallow water and its high vertical accuracy. Use of image source is also efficient for extraction of features by analysis of its image source. Therefore, aerial orthoimage also have been used for river zone mapping tasks due to its image source and its higher accuracy in horizontal direction. Due to these advantages, in this paper, research on three dimensional levee line mapping is implemented using LiDAR and aerial orthoimage separately. Accuracy measurement is implemented for both extracted lines generated by each data using the ground truths and statistical comparison is implemented between two measurement results. Statistical results show that the generated 3D levee line using LiDAR data has higher accuracy than the generated 3D levee line using aerial orthoimage in horizontal direction and vertical direction.

Design of Discriminant Function for White and Yellow Coating with Multi-dimensional Color Vectors (다차원 컬러벡터 기반 백태 및 황태 분류 판별함수 설계)

  • Lee, Jeon;Choi, Eun-Ji;Ryu, Hyun-Hee;Lee, Hae-Jung;Lee, Yu-Jung;Park, Kyung-Mo;Kim, Jong-Yeol
    • Korean Journal of Oriental Medicine
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    • v.13 no.2 s.20
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    • pp.47-52
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    • 2007
  • In Oriental medicine, the status of tongue is the important indicator to diagnose one's health, because it represents physiological and clinicopathological changes of inner parts of the body. The method of tongue diagnosis is not only convenient but also non-invasive, therefore, tongue diagnosis is one of the most widely used in Oriental medicine. But tongue diagnosis is affected by examination circumstances a lot. It depends on a light source, degrees of an angle, doctor's condition and so on. So it is not easy to make an objective and standardized tongue diagnosis. As part of way to solve this problem, in this study, we tried to design a discriminant function for white and yellow coating with multi-dimensional color vectors. There were 62 subjects involved in this study, among them 48 subjects diagnosed as white-coated tongue and 14 subjects diagnosed as yellow-coated tongue by oriental doctors. And their tongue images were acquired by a well-made Digital Tongue Diagnosis System. From those acquired tongue images, each coating section were extracted by oriental doctors, and then mean values of multi -dimensional color vectors in each coating section were calculated. By statistical analysis, two significant vectors, R in RGB space and H in HSV space, were found that they were able to describe the difference between white coating section and yellow coating section very well. Using these two values, we designed the discriminant function for coating classification and examined how good it works. As a result, the overall accuracy of coating classification was 98.4%. We can expect that the discriminant function for other coatings can be obtained in a similar way. Furthermore, if an automated segmentation algorithm of tongue coating is combined with these discriminant functions, an automated tongue coating diagnosis can be accomplished.

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A Study about the Effects of Intellectual Property Investment and Management on the Value of Intangible Assets of Firms (지식재산 투자와 관리가 기업의 무형자산가치에 미치는 영향에 대한 연구)

  • Sung, Oong-Hyung;Jo, Kyeong-Seon
    • Journal of Korea Technology Innovation Society
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    • v.12 no.2
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    • pp.291-311
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    • 2009
  • Intellectual Property(IP) investment and its management are an key driver to create corporate value and intangible asset value through corporate's competitiveness. The purposes of this study are to survey capability of IP management and assess the effects of IP investment and its management on the separation into groups of intangible asset value. In order to attain those purposes of this study, sample companies were taken and categorized into three groups by the level of intangible asset value ratio, and data for IP investment such as R&D expenditure and advertising expenditure were collected from 90 manufacturing companies, and data for IP management capability about patent, design and brand were taken through survey. The final results showed as followed: First, IP management capability were generally not sufficient in the results of survey. Second, mean vector for the four variables were significantly different among three groups in multivariate analysis variance. Third, the order of their contribution to separating the groups were R&D expenditure, advertising expenditure, patent management, management of design and brand in canonical variate analysis. Fourth, R&D and patent management capability were significantly related to the separation of three groups, while advertising expenditure were not significant and management of design and brand were not sure of Significance in multinomial logit discriminant analysis. Fifth, exploratory power of the discriminant model were estimated by 53% in classification analysis. Finally, strategic policy for IP investment and its management should be taken urgently to create intangible asset value and to improve the capability of its management.

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Filter-Bank Based Regularized Common Spatial Pattern for Classification of Motor Imagery EEG (동작 상상 EEG 분류를 위한 필터 뱅크 기반 정규화 공통 공간 패턴)

  • Park, Sang-Hoon;Kim, Ha-Young;Lee, David;Lee, Sang-Goog
    • Journal of KIISE
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    • v.44 no.6
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    • pp.587-594
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    • 2017
  • Recently, motor imagery electroencephalogram(EEG) based Brain-Computer Interface(BCI) systems have received a significant amount of attention in various fields, including medicine and engineering. The Common Spatial Pattern(CSP) algorithm is the most commonly-used method to extract the features from motor imagery EEG. However, the CSP algorithm has limited applicability in Small-Sample Setting(SSS) situations because these situations rely on a covariance matrix. In addition, large differences in performance depend on the frequency bands that are being used. To address these problems, 4-40Hz band EEG signals are divided using nine filter-banks and Regularized CSP(R-CSP) is applied to individual frequency bands. Then, the Mutual Information-Based Individual Feature(MIBIF) algorithm is applied to the features of R-CSP for selecting discriminative features. Thereafter, selected features are used as inputs of the classifier Least Square Support Vector Machine(LS-SVM). The proposed method yielded a classification accuracy of 87.5%, 100%, 63.78%, 82.14%, and 86.11% in five subjects("aa", "al", "av", "aw", and "ay", respectively) for BCI competition III dataset IVa by using 18 channels in the vicinity of the motor area of the cerebral cortex. The proposed method improved the mean classification accuracy by 16.21%, 10.77% and 3.32% compared to the CSP, R-CSP and FBCSP, respectively The proposed method shows a particularly excellent performance in the SSS situation.

The Effect of Sensory Stimulation on Postural Tremor at Index Finger of Patients with Essential Tremor (ET) (본태성 진전 환자의 검지에서의 자세성 진전에 대한 감각자극 효과)

  • Lee, S.K.;Kim, J.W.;Kwon, Y.R.;Lee, Y.J.;Lee, J.H.;Eom, G.M.;Kwon, D.Y.;Lee, C.N.;Seo, Y.M.;Kim, M.K.;Park, K.W.;Jeong, H.C.;Manto, M.
    • Journal of Biomedical Engineering Research
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    • v.34 no.3
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    • pp.129-134
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    • 2013
  • The essential tremor is an involuntary oscillatory movement of body parts. Conventional treatments of essential tremor have little effects in some patients and also leads to significant side effects. Alternative to these treatments, sensory stimulation may have beneficial effects on the essential tremor. The purpose of this study was to analyze an effect of sensory stimulation on essential tremor. Ten patients with essential tremor ($67.4{\pm}8.82$ yrs, 5 men and 5 women) participated in this study. Three-axis gyro sensors were attached on index finger, hand and forearm of patients. Task of 'arms outstretched forward' was performed with and without sensory stimulation. Vectorsum of three dimensional angular velocities (pitch, roll, yaw) was calculated. Outcome measures included root-meansquare (RMS) mean of the vector-sum amplitude, total power, peak power and peak frequency. RMS amplitude, total power and peak power were reduced by sensory stimulation (p < 0.05). Peak frequency was not affected by sensory stimulation. The results indicate that the sensory stimulation is useful to suppress the essential tremor.

Regional Divisions of Honam Region by Summer Precipitation and Variation Patterns over a Period of 10 days (하계강수량과 그 순변화형에 의한 호남지방의 지역 구분)

  • Park, Hyun-Wook
    • Journal of the Korean association of regional geographers
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    • v.11 no.1
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    • pp.101-113
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    • 2005
  • The seasonal variation and frequency of precipitation phenomenon of the Honam region in summer show strong local weather phenomena because of its topographical and geographical factors in southwestern area of Korea. The propose of this treatise is to induce variation patterns over a period 10 days of summer precipitation(that is one of the important elements of the precipitation characteristics), clarify the variations of their space scales, and study the subdivision of precipitation regions in Honam according to the combinations of precipitation amounts and variation pattern over a period of a 10 days of summer precipitation, using the mean values during the years 1994$\sim$2003 at 79 stations(the surface synoptic stations 16 AWS 63) of Honam region. The classified precipitation of a period of 10 days summer precipitation, and the principal component vector and the amplitude coefficient by the principal component analysis were used for this study. The characteristics of variation pattern over a period of 10 days of summer precipitation can be chiefly divided into four categories and the accumulated contributory rate of these is 78.0%. And the change patterns of summer precipitation during a period of 10 days in honam region are classified into 11 types from A to K And regional divisions of summer precipitation in Honam region can be classified into 18 types.

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