• Journal of information and communication convergence engineering
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• 제16권2호
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• pp.72-77
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• 2018

This paper presents a novel channel capacity maximization method for a distorted $2{\times}2$ line-of-sight (LOS) multiple-input multiple-output (MIMO) link. A LOS MIMO link may be distorted by the influence of environmental factors such that the channel capacity of the LOS MIMO link may be degraded. By using the proposed method, the channel capacity of a distorted $2{\times}2$ LOS MIMO link can be the same as that of the ideal $2{\times}2$ LOS MIMO link. The proposed method employs an additional receiver antenna to maximize the channel capacity. In contrast to a $3{\times}2$ LOS MIMO link, a receiver circuit for a third receiving antenna is not necessary. Hence, the receiver for the proposed method is much simpler than that for a $3{\times}2$ LOS MIMO link. We determine the optimal position of the additional receiver antenna analytically. Simulation results show that the channel capacity can approach the ideal using the proposed method.

• The Journal of Korean Physical Therapy
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• 제31권4호
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• pp.248-253
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• 2019

Purpose: To improve pulmonary function and decrease in balance ability with increasing forward head position and vertebral curvature, we applied Figure-8 brace to confirm the immediate effect on vital capacity and balance and to see if it is applicable. Methods: A total of 34 elderly women aged 65 or older and young women in their 20s with FHP were screened to measure vital capacity, measuring the forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC), and measuring the foot pressure to see the change in balance. For statistical analysis, the difference between pre and post values was compared using pared t-test. Results: As a result of vital capacity measurements, there was no significant difference between FEV1 and FVC for women over 65 years old (p>0.05). Young women in their 20s had no significant difference in FEV1 (p>0.05), and FVC had significant differences (p<0.05). In measuring foot pressure to measure balance, both women aged 65 and above and young women in their 20s had a significant decrease in anterior foot pressure, and a significant increase in posterior foot pressure (p<0.05). Conclusion: The results of this study did not positively affect the vital capacity of elderly women with FHP. However, the significant increase in vital capacity of young women in their 20s suggests that contraction of the abdominal muscle is necessary during forced expiration. Therefore, it is believed that proper application and therapeutic interventions should be combined when applying Figure-8 brace.

• 한국농공학회지
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• 제39권2호
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• pp.124-133
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• 1997

Pile load test is good for estimating pile bearing capacity, but using this method is limited by time and cost required. Dynamic and static method is more convenient and economical, but confidence of estimated value by dynamic and static method are lower than that of pile load test. After being compared pile bearing capacity data obtained from pile load test with those of other two methods, the results from this study were summarised as follows. For allowable bearing capacity values greater than 175t per pile, bearing capacity acquired from static method was higher than that acquired from pile load test, whereas bearing capacity acquired from pile load test was higher than that acquired from static method for values under 175 per pile. It was that variance of bearing capacity was large when bearing capacity obtained by dynamic method was higher than 250t. Also bearing capacity based on dynamic method was higher than that based on pile load test. Allowable bearing capacity get from dynamic method suggested that carefull precautions are necessary in application for allowable bearing capacity values higher than 2S0ton per pile.

• 한국실내디자인학회논문집
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• 제15권6호
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• pp.139-149
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• 2006

Because of economic growth and the social trend to respect individuality, people's average commodity volume tends to increase. It makes people perceive the importance of storage space. The storage planning without consideration of commodity volume in the apartment can not satisfy the needs of residents. This study is developed focused on the $85m^2$ apartment which is the most representative and general type. The objectives of the study are to investigate the storage-capacity of $85m^2$ apartment offered by 4 construction companies to know the present storage condition, to investigate the average volumes and type of commodities in 30 families located in Seoul and Kyungkido to produce the necessary storage-capacity, and lastly to produce optimal storage-capacity and proportion of optimal storage-capacity considering the volume of the furniture owned by each resident. The results of the study are 1) the storage capacity for commodity volume in $85m^2$ apartment is $19.41m^3$. 2) the optimal storage-capacity which only counts the storage volume of built-in furniture is $17.14m^3$ 3) the proportion of optimal storage-capacity is 9.5% of the house-capacity.

• Journal of Information Technology Applications and Management
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• 제22권3호
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• pp.129-141
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• 2015

The purpose of this study is to provide an explanation for the association between the characteristics of a network and the type of innovation by considering the effect of absorptive capacity. To do so, this study examined the moderating effects of absorptive capacity on the characteristics of network-innovation relationship in a technical-driven venture company. In order to obtain a better understanding about consequences caused by interfirm network, information was obtained from 169 Korean IT venture companies. Results confirmed that the network diversity is positively associated with exploration. Our results also suggested that the network strength is positively associated with exploitation. Finally, we found a positive two-way interaction between absorptive capacity and the network diversity-exploration relationship. Then, we discussed implications and directions for future research.

• ETRI Journal
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• 제30권3호
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• pp.355-364
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• 2008

Multiple-input multiple-output (MIMO) systems can provide significant increments in capacity; however, the capacity of MIMO systems degrades severely when spatial correlation among multipath channels is present. This paper demonstrates that the influence of shadowing on the channel capacity is more substantial than that of multipath fading; therefore, the shadowing effect is actually the dominant impairment. To overcome the composite fading effects, we propose combining macroscopic selection diversity (MSD) schemes with MIMO technology. To analyze the system performance, the capacity outage expression of MIMO-based MSD (MSD-MIMO) systems using a characteristic function is applied. The analytic results show that there are significant improvements when MSD schemes are applied, even for the two-base-station diversity case. It is also observed that the effect of spatial correlation due to multipath fading is almost negligible when multiple base stations cooperatively participate in the mobile communication topology.

• 환경영향평가
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• 제20권1호
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• pp.37-48
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• 2011

Recently, the social and environmental functions of nature river are important due to the increase of expectation for river restoration. So it should be considered the effect of vegetation affecting the conveyance capacity and hydraulic resistance. However, it has not yet proposed a objective standard and modeling method to estimate the effect of conveyance capacity according to vegetaion distribution in the watercourse such as water level or velocity. Therefore, this study simulates the variations of water level and velocity using 3-dimensional hydrodynamic model, EFDC, to consider a conveyance capacity in downstream of the Soyang Reservoir. The simulation results were validated using statistical index such as F-test and T-test. As results, the water level rises about 0.01 to 0.47m and velocity difference are about -0.95m/s to 0.23m/s.

• 대한한의학방제학회지
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• 제21권2호
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• pp.165-172
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• 2013

Objectives : This experiment was performed in order to study the effect of Maekmundong-tang on dyspnea patients. Methods : This study involved 14 dyspnea patients from March 1, 2012 to May 31, 2012. Lung capacity of the patients is evaluated with Peak flow meter. Results : Maekmundong-tang administration was revealed effect on dyspnea patients' lung capacity. Conclusions : It was found that Maekmundong-tang administration was effective on dyspnea patients' lung capacity. The mean degree of improvement was 21.79(L/min). It was shown that the more mild dyspnea level was, the more effective and short-term administration more effective.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.843-845
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• 2005

The uncertainty of long term electricity plan consists of the uncertainty of demand forecast and additional generating capacity. Demand forecast is clearly improved the accuracy than the past through improving forecasting methods. However, the uncertainty of additional generating capacity is increased due to the change of market environment. In an operation by a sole utility, additional generating capacity would be possible by the regulation of government. Currently the generation companies have spined off from KEPCO and some IPPs participate the electricity market. It increases the uncertainty due to weakened regulation. Also the environment movement by NGOs and occurrence of civil affairs cause the increase of uncertainty. This research would analyze the current situation on the uncertainty of additional generating capacity and construction delays. Furthermore this research would present the plan to reflecting it in long term electricity plan.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.1156-1163
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• 2010

The bi-directional high pile load test(BDH PLT) does not have weaknesses found in the existing bi-directional low pile load test(BDL PLT); it has strong economics, is unbound by load capacity limit and secures quality stability of working piles. In this study, Verification the field found a very high capacity level of stability and reliability of the BDH PLT, as well as outstanding field applicability. Field verifications reaffirmed the advantage of the BDH PLT device, which was capable of loading 90 MN capacities as maximum. It was also found to be durable enough to load high capacity with ease.