• Korean Journal of Applied Biomechanics
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• v.25 no.3
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• pp.323-333
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• 2015

Objective : The purpose of this study was to investigate the changes of gait patterns and muscle activations with increased loads during stair walking. Also, it can be used as descriptive data about continuous stair walking in a real life setting. Method : Twelve sedentary young male adults(Age: $27.0{\pm}1.8yrs$, Weight: $65.8{\pm}9.9kg$) without any lower extremity injuries participated in this study. Participants performed stair walking up 7 floors and their ascending and descending motion on each floor was analyzed. A wireless electromyography(EMG) were attached on the Rectus Femoris(RF), Biceps Femoris(BF), Gastrocnemius(GN), Tibialis Anterior(TA) muscle to calculate integrated EMG(iEMG), median frequency(MDF) and co-contraction index(CI). Chest and left heel accelerometer signal were recorded by wireless accelerometer and those were used to calculate approximate entropy(ApEn) for analyzing gait pattern. All analyses were performed with SPSS 21.0 and for repeated measured ANOVA and Post-hoc was LSD. Results : During ascending stairs, there were a statistically significant difference in Walking time between 1-2nd and other floors(p=.000), GN iEMG between 2-3th and 6-7th(p=.043) floor, TA MDF between 1-2nd and 5-6th(p=.030), 6-7th(p=.015) floor and TA/GN CI between 2-3th and 6-7th(p=.038) floor and ApEn between 1-2nd and 6-7th(x: p=.003, y: p=.005, z: p=.006) floor. During descending stairs, there were a statistically significant difference in TA iEMG between the 6-5th and 3-2nd(p=.026) floor, and for the ApEn between the 1-2nd and 6-7th(x: p=.037, y: p=.000, z: p=.000) floor. Conclusion : Subjects showed more regular pattern and muscle activation response caused by regularity during ascending stairs. Regularity during the first part of stair-descending could be a sign of adaptation; however, complexity during the second part could be a strategy to decrease the impact.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.12
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• pp.73-82
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• 2008

There are several approaches for reducing the ROB(Reorder Buffer) complexity in processors. The one technique that makes the simplest ROB ports relies on a distributed implementation that spreads the centralized ROB structure across the functional units(FUs). Each distributed buffers are decided on the size of them by workload of the functional units. The performance of the processor depends on the size of distributed ROB. However, most of previous works have depended on the simulation results to decide the optimsize of distributed ROB. In this Paper, we use an analytical model based on the M/M/1 Queuing theory to determine the optimum size of each distributed ROB. Our schemes are evaluated by using the simulation performed by the CPU2000 benchmarks. We are able to choose the optimum size of distributed ROB showing the 99.2% performance compared with existing superscalar processors. We can save 82% hardware resources in ports and reduce more than 30% of delay when ROB and distributed ROB proposed in this paper are designed by HDL.

• Journal of the Korean earth science society
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• v.26 no.5
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• pp.387-394
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• 2005

We have analyzed the science-gifted educational program (year 2002) at the Seoul National University in terms of its educational objectives, scientific models, and cognitive processes in scientific inquiry in order to provide insights into developing and improving science-gifted educational program. We assumed the following items as important factors for teaching scientifically gifted students: higher-order thinking skills involving synthesis domain in the educational objectives, highly abstract nature and complexity in the scientific models, cognitive processes of planning experiments in the cognitive processes in scientific inquiry. According to the analyzed results, the program has the following characteristics: (1) the rates of both higher and lower-order thinking skill domain in the educational objectives are similarly high, but the rate of synthesis domain is relatively low; (2) in the case of the scientific models, the rate of the multiple concepts and/or processes model is relatively low, while the level of the abstractness is relatively on average (3) cognitive processes of authentic scientific inquiry is not thoroughly reflected in the scientific inquiry activities, and very few cognitive processes of planning experiments factor is reflected. Therefore, we conclude in the synthesis domain in the educational objectives, multiple concepts and/or processes model, and cognitive processes of planning experiments should be especially reflected more on the science-gifted educational program in order to serve the needs of scientifically gifted students.

• Journal of the Korean Geotechnical Society
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• v.20 no.7
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• pp.5-14
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• 2004

The observational design and construction method in tunnels is becoming important recently. In many tunnels, enormous cost and time are consumed to cope with the failing or sliding of rock blocks, which could not be predicted because of the complexity of rock discontinuities. It is difficult to estimate the properties of rock masses before the construction. In this paper, a new observational design and construction method in tunnels are proposed, and then applied to the example of the very large cross section tunnel based on actual discontinuity information observed in situ. The items examined in developing a program for the new observational design and construction method are the following ones: generality, precision, high speed, and friendly usability. At the very large cross section tunnel, 7 key blocks were judged to be unstable because they could not be supported by standard supports. Supplementary supports were installed to these 7 key blocks before the excavation. It is possible to detect key blocks all along the tunnel exactly by using the numerical analysis program developed for the new observational design and construction method in the very large cross section tunnel. This computer simulation method with user-friendly interfaces can calculate not only the stability of key blocks but also the design of supplementary supports.

• Korean Journal of Construction Engineering and Management
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• v.12 no.4
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• pp.97-105
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• 2011

As many stakeholders are taking part in the Housing Redevelopment Project, their opinion mediation is considering very important issues. Thus disputes on projects are inevitable due to complexity of interest. To effectively progress the project, this paper analyze the risk factors by phase in implementation phase that the association participates in person. We identify 50 of risk factors in implementation phase by reviewing and analyzing related studies and actual cases of disputes, then we present 26 of risk factors through experts interview. Also, we calculate weights of risk factors by using AHP for quantitatively analyzing them and present final weights and priorities of risk factors by summing weights of risk factors by phase. In results, it is found that 'the inappropriateness of the Management Disposal Plan' in management disposal plan phase and 'the inappropriateness of the Project Implementation Plan' are the most significant risk factors. To maximize the utilization of risk factors analyzed, we present the checklists that can be aware of these risks in advance and prevent these risks. Based on these findings, if risk factors in implementation phase are managed actively, the housing redevelopment project will be performed more effectively.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.12A
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• pp.1922-1931
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• 1999

A multicast traffic’s feature is the function of providing a point to multipoints cell transmission, which is emerging from the main function of ATM switch. However, when a conventional point-to-point switch executes a multicast function, the excess load is occurred because unicast cell as well as multicast cell passed the copy network. Additionally, due to the excess load, multicast cells collide with other cells in a switch. Thus a deadlock that losses cells raises, extremely diminishes the performance of switch. An input queued switch also has a defect of the HOL (Head of Line) blocking that less lessens the performance of the switch. In the proposed multicast switch, we use shared memory switch to reduce HOL blocking and deadlock. In order to decrease switch’s complexity and cell's processing time, to improve a throughput, we utilize the method that routes a cell on a separated paths by traffic pattern and the scheduling algorithm that processes a maximum 2N cell at once in the control part. Besides, when cells is congested at an output port, a cell loss probability increases. Thus we use the Output Memory (OM) to reduce the cell loss probability. And we make use of the method that stores the assigned memory (UM, MM) with a cell by a traffic pattern and clears the cell of the Output memory after a fixed saving time to improve the memory utilization rate. The performance of the proposed switch is executed and compared with the conventional policy under the burst traffic condition through both the analysis based on Markov chain and simulation.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.11B
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• pp.1133-1141
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• 2009

In this paper, we present a distributed fault-tolerant topology control protocol that configure a wireless sensor network to achieve k-connectivity and (k+1)-coverage. One fundamental issue in sensor networks is to maintain both sensing coverage and network connectivity in order to support different applications and environments, while some least active nodes are on duty. Topology control algorithms have been proposed to maintain network connectivity while improving energy efficiency and increasing network capacity. However, by reducing the number of links in the network, topology control algorithms actually decrease the degree of routing redundancy. Although the protocols for resolving such a problem while maintaining sensing coverage were proposed, they requires accurate location information to check the coverage, and most of active sensors in the constructed topology maintain 2k-connectivity when they keep k-coverage. We propose the fault-tolerant topology control protocol that is based on the theorem that k-connectivity implies (k+1)-coverage when the sensing range is at two times the transmission range. The proposed distributed algorithm does not need accurate location information, the complexity is O(1). We demonstrate the capability of the proposed protocol to provide guaranteed connectivity and coverage, through both geometric analysis and extensive simulation.

• Journal of Distribution Research
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• v.17 no.3
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• pp.93-113
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• 2012

Early conflict research in channel and organization area have focused on the definition of conflict construct, its cause, consequence and identified conflict resolution management. Recent studies about conflict, however, have explored new assumption of complexity, a multidimensional conflict construct, contextual conflict management strategies, positive and negative conflict/consequence, and the conflict resolution strategy. Although many literatures exists on channel conflict resolution, little research has been done about relationship learning and performance from conflict resolution perspective. This study explores how channel members can achieve a relationship learning, as a conflict resolution mechanism, which enhance co-created value in marketing channel relationship. Therefore we propose that conflict resolution strategies(collaborating behavior and avoiding behavior) influence channel performance(effectiveness and efficiency) through relationship learning processes(learning via information exchange, joint interpretation and coordination, relationship-specific knowledge memory), in view of buyer-seller relationship. The research model is shown at

• Journal of Korea Technology Innovation Society
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• v.18 no.2
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• pp.292-317
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• 2015

As modern science and technology and warfare become to be advanced and precise, the weapon systems becomes more complex based on state-of-the-art technology. Therefore, firms in the defense industry continue to accelerate research and development for up-to-date weapon systems with high complexity which urge the firms to collaborate with the external organizations to obtain the knowledge required and eventually to reduce costs and risk. This study tries an empirical study about the effect of collaboration on the innovation performances from the network analysis perspective. By surveying collaboration relationships among 530 firms in the Korean defense industry, we analyzed the alliance network of the defense industry. Network centrality including degree, closeness, and betweenness centralities is investigated and then the relationship among the network centrality property, internal R&D capabilities and innovation is analysed. The results show that firms with high internal R&D capabilities place the firm at center of the network. On the other hand, except for the firms with highly connected centrality, no relationship was found between the internal R&D capabilities and its performance and in turn. these capabilities had both direct and indirect effects on innovation performances through mediated collaboration among firms. This study implied that Korean firms with a high internal R&D capabilities in the defense industry which utilize knowledge, information and resources within the network more frequently show more innovative performance. This result claims the policy makers to participate more firms in fostering open innovation for the defense industry.

• Journal of Oriental Neuropsychiatry
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• v.23 no.4
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• pp.69-94
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• 2012

Objectives : The goals of the present study are to assess children with tic disorders, their clinical characteristic and to prove the effectiveness of herbal treatments of tic disorders. Methods : The present study was conducted from January 2006 to April 2011, with 200 out-patient children between the age of 6 to 12 diagnosed with tic disorder (after excluding 10 children who could not be clearly diagnosed) at the "H'herbal medicine clinic located in Seoul. Of these 200 children, we have evaluated the epidemiology and clinical manifestation, and analyzed the results of herbal medicine treatments. Results : 1. Among the children diagnosed with tic disorder, TTD was most prevalent (43.3%) and males were more likely than females to express tics (5.45:1). Children with TD sought help significantly later (average age of 9.03 years) than the other types. 2. The analysis results of herbal medicine treatments are as follows. Compared to the pre-treatment assessment, children who received herbal medicine treatment for more than three months (n=52) showed a marked decrease in symptoms of motor tics (the number of motor tics, frequency, severity, complexity) and vocal tics (the number of vocal tics, frequency, severity), in the impairment level of combined tics (motor and vocal tics together) and in the overall score. Conclusions : In conclusion, we apprehended demographic and clinical characteristics of tic disorder patients who visited a Korean traditional medicine clinic by analyzing the psychological assessment results. Furthermore, we identified the effectiveness of herb formula in tic disorder.