• The Journal of Korean Physical Therapy
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• v.24 no.1
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• pp.29-34
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• 2012

Purpose: The purpose of this study was to evaluate the difference between respiratory function and speech production, according to the seat surface inclination while in the sitting position. Methods: Respiratory function (FVC, FEV1) and speech production (inspiratory frequency, unit reading time, paragraph reading time) were measured in 3 sitting conditions: horizontal seat surface, seat surface tilted forward 15 degrees, and seat surface tilted backward 15 degrees. Results: We found that the mean values of FVC and FEV1 were statistically significant different according to three types of sitting positions (p<0.05). The following result was observed: forward tilted sitting > horizontal sitting > backward tilted sitting. There was no significant difference in speech production between the different positions. Respiratory function and speech production had a significantly negative correlation in the forward tilted condition and the backward tilted condition. Conclusion: This finding suggests that the seat surface inclination have an effect on respiratory function. Especially, forward tilted sitting may be an effective posture that may help increases the respiratory function.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.10
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• pp.164-171
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• 1999

An optimum blank design technology is required for near-net of net-shape cold forming using sheets. Originally, the backward tracing scheme has been developed for preform design in bulk forming, and applied to several forming processes successfully. Its key concept is to trace backward from the final desirable configuration to an intermediate preform of initial blocker. A program for initial blank design in sheet forming which contains the capabilities of forward loading simulation by the finite element method and backward tracing simulation, has been developed and proved the effectiveness by applying to a square cup stamping process. In the blank design of square cup stamping, the backward tracing program can produce an optimum blank configuration which forms a sound net-shape cup product without machining after forming. Another general application appears in the blank design of a cup stamping with protruding flanges, one of typical automobile components. The blank configurations derived by backward tracing simulation have been confirmed by a series of loading simulations. The approach or decision of an initial blank configuration presented in this study will be a milestone in fields of sheet forming process design.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.7B
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• pp.481-488
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• 2005

As the demand on the multimedia application increases, the congestion control algorithm for the multimedia applications becomes an important research issue. The ultimate goal of congestion control is to adapt the trans-mission rate at the sender to the mont of network resource available on the forward path. In general, the congestion control algorithms use the round trip time(RTT) to estimate the network congestion on the forward path. however, since the RTT includes the delay on both forward and backward paths, it is possible for the algorithms using the RTT to make a wrong decision such as deciding the congestion on the forward path due to the congestion built on the backward path. In this paper, we enhance the performance of RRC-OTT(Receiver-based rate control with one-way Trip Time) algorithm, which uses the one-way trip time(OTT) to estimate the network congestion. By separating the estimation mechanism on the forward path from the backward path, the performance of RRC-OTT algorithm is hardly affected by the congestion built on the backward path.

• Journal of The Korean Society of Integrative Medicine
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• v.12 no.3
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• pp.83-91
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• 2024

Purpose : This case study aimed to investigate the effects of backward walking exercises with a front-loaded bag on craniovertebral angle (CVA), craniorotational angle (CRA), and gait variables in subjects with forward head posture (FHP). Methods : Two individuals in their twenties with FHP performed backward walking exercises on a treadmill while carrying a front-loaded bag with a load equivalent to 20 % of their body weight, for 30 minutes per day, three times a week, over two weeks. CVA and CRA were measured before and after the intervention using side view photographs taken from 1.5 meters away. CVA was calculated by marking C7, the tragus of the ear, and the outer canthus of the eye, and CRA was determined using the same landmarks. Image J software was used for angle analysis, with measurements taken three times and averaged. Gait variables such as step length and cadence were recorded using a step analysis treadmill and analyzed with the software included with the equipment, with measurements taken at baseline and after the two-week intervention. Results : Both participants demonstrated notable improvements in the CVA, indicating enhanced head alignment relative to the cervical spine. There was also a marked decrease in the CRA, suggesting a reduction in rotational misalignment. Although differences were observed in gait variables, such as step length and cadence, these changes were not consistent across measurements. The results suggest that backward walking exercises with a load carried in front can positively influence postural adjustments by aligning the cervical spine in individuals with FHP. Conclusion : The findings of this case study indicate that backward walking exercises with a front-loaded bag can effectively improve cervical spine alignment in individuals with FHP. Differences were observed in gait variables, such as step length and cadence, but these changes were not consistent across measurements. Future studies should explore these effects more comprehensively and consider optimizing the exercise protocol for better therapeutic outcomes.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.16 no.2
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• pp.76-81
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• 2010

Purpose: This study examined how the degrees of muscle activity of Rectus Femoris and Tibialis Anterior during the four phases of walking vary according to three different treadmill slopes of $0^0$, $7^0$, and $15^0$. Methods: Subjects were 14 randomly selected healthy students attending G University in Seoul, Korea who had never had articular problems with lower limb and had no difficulties walking at the time of study. Results: 1) With respect to Rectus Femoris, in every phase of both forward and backward walking, there were significant differences among all of the slope degrees (p <.05), while the activity increased with increased slope degrees in every phase of backward walking. 2) For Tibialis Anterior, only in P2 and P3 of both forward and backward walking there were significant differences in every slope (p <.05). Conclusion: Both Rectus Femoris and Tibialis Anterior were found to be more active during backward walking compared to backward walking. In addition, the activity degree of Rectus Femoris was high between the early part of two foot support phase and the early part of one foot support phase, whereas that of Tibialis Anterior was high between the early part of one foot support phase and the latter part of both foot support phase.

• Physical Therapy Korea
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• v.23 no.3
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• pp.1-10
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• 2016

Background: Gait problems appear in most stroke patients. Commonly, stroke patients show the typical abnormal gait patterns, such as circumduction, genu recurvatum, and spastic paretic stiff-legged gait. An inclined treadmill gait exercise is good for gait problems of stroke patients. In addition, the backward walking training has been recommended in order to improve the component of the movement for the forward walking. Objects: The purpose of this study to investigated the effects of backward walking with inclined treadmill training on the gait in chronic stroke patients. Methods: A total of 30 volunteers were randomly allocated to two groups that walked on an inclined treadmill: the experimental group ($n_1=15$), which walked backward, and the control group ($n_2=15$), which walked forward. To measure the improvement of the patients' gait, a Figure of Eight Walking Test (F8W), Four Square Step Test (FSST), and Functional Gait Assessment (FGA) were performed. We also measured spatio-temporal gait variables, including gait speed, cadence, stride length, and single limb support using a three-axial wireless accelerometer. The measurements were taken before and after the experiment. The Wilcoxon signed-rank test was used to compare both groups before and after the interventions. The Mann-Whitney U test was used for the comparisons after the interventions. The statistical significance was set at ${\alpha}=.05$. Results: Before and after experiment, all dependent variables were significantly different between the two groups (p<.05). As compared to the control group, the experimental group showed more significant improvements in F8W, FSST, speed, cadence, stride length, and single limb support (p<.05); however, FGA in this group was not significantly different from the control (p>.05). Conclusion: Our results suggest that backward walking on an inclined treadmill is more effective for improving the gait of stroke patients than forward walking.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.11
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• pp.7285-7292
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• 2015

The purpose of this study was to investigate possibility of a forward gait with backward mechanism(dance gait) as rehabilitation and/or walking exercise by means of biomechanical variables. Thirteen professional women dancers(age, $21.1{\pm}1.3yrs$; height, $159.3{\pm}7.2cm$; body mass, $45.1{\pm}8.4kg$)participated in this study. We found that speed, stride length and double limb support time of a dance gait were more greater than backward gait, but stride width of dance gait less than a backward gait. Maximum RoMs, moments and powers of the lower limb joints on a dance gait were more frequent than a backward dance. These results were judged to be sufficient by the possibility of dance gait as rehabilitation and walking exercise.

• The Journal of the Acoustical Society of Korea
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• v.27 no.1E
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• pp.25-29
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• 2008

The projection approximation subspace tracking (PAST) is one of the attractive subspace tracking algorithms, because it estimatesthe signal subspace adaptively and continuously. Furthermore, the computational complexity is relatively low. However, the algorithm still has room for improvement in the subspace estimation accuracy. In this paper, we propose a new algorithm to improve the subspace estimation accuracy using a normally ordered input vector and a reversely ordered input vector simultaneously.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.6
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• pp.1425-1429
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• 1996

A conventional sequence search algorithm for PRI analysis occurs the harmonic problem under missing pulses. An improved PRI analysis algorithm is proposedto remedy the harmonic problem. After dividing an overall PRI range into subbands withoug harmonic, a sequence search is done into forward and backward in time. The proposed algorithm increases the preformance compared with that of conventional sequence search algorithm.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.274-275
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• 2000

This paper introduces new ordering algorithms using the graph of data structure and forward/backward substitution of LU decomposition using recursive function. The performance of the algorithm is compared with Tinney's algorithm using 14 bus systems. Test results show that the new fill-in element of Jacobian matrix using the proposed ordering algorithm is same as that of Tinner scheme 3 and the forward/backward substitution can reduce the computation time