• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1991.04a
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• pp.41-45
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• 1991

구조 진동에 의해 발생하는 Relative Sound Power를 계산하는 문제가 최근 에 중요시되고 있다. 이 논문에서는 조화적인 집중하중에 대한 무한 탄성보 에서 방출하는 Relative Sound Power를 연구한다. Sound Power는 수치적으 로 적분되고 몇가지 인자들의 함수로써 적분인자를 표시하였다. Keitie와 Peng[2]는 진동하는 보로부터의 방출하는 Relative Sound Power에 대한 하 중 길이의 효과, 그리고 water 하중을 받는 보에서 방출하는 Acoustic radiation에 대한 Source 운동과 기초 강성의 효과를 연구하였다. 보의 진동 응답에서 light fluid loading과 heavy fluid loading에 의한 양쪽의 반응을 고 려한다. 보에는 기초 강성과 Damping 그리고 장력이 작용한다. water 하중 과 air 하중을 받는 보에서 Damping의 변화에 대한 보로부터 방출하는 relative sound power의 크기를 결정하였다. 일반적으로 인장력보다 압축력 이 작용할 때 relative sound power level이 크다는 것을 알고 있다. 실제로 인장력이나 압축력이 보에 작용할 때 relative sound power에 얼마나 영향을 미치는가를 계산하였다. 그리고 진동계로부터 방출하는 sound fluid loading 과 기초 강성에 기인한 복잡한 효과를 해석하였다. 이 논문의 목적은 강성계 수와 wavenumber 비, 그리고 fluid loading에 대한 sound power의 응답에 대하여 설명하고자 한다.

• Journal of Korean Academy of Nursing
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• v.27 no.1
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• pp.169-177
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• 1997

This study aims at empirically clarifying the relationship between power and the interpersonal conflict, including nurses' understanding of their relative power, the causes of interpersonal conflicts with the nurses, and strategies to resolve conflicts, in order to understand how nurses' relative power affect their conflicts. For the empirical survey, the population was defined as all the nurses working at a medical organization in Seoul, Korea. 1083 nurses were selected as the sample for the questionnaire survey and statistical analyses. For the sampling, 32 medical organizations were selected by a stratified random method and sub-samples were arbitrarily drawn from each organization to obtain the final sample of 1083 nurses who responded to the questionnaire designed by the reseacher. According to the result of the study, most nurses experience conflict more than once a month, and 70.4% of the respondents answered that interpersonal conflicts were directly or indirectly caused by power relations. which indicates that they perceive power relations as the main cause of interpersonal conflicts. Nurses experienced the most conflicts with interns and residents(29.7%), then patients and their families(24.3%), higher-positioned nurses(12.3%), nurse colleagues(7.7%), lower-positioned nurses(6.5%), and staff doctors(5.1%). If we classify these into three groups. the frequency of the conflicts, from most frequent to least. is in the order of doctors. nurses, and patients. In terms of relative power, nurses perceive that they have greater power than patients and their families, lower-positioned nurses, and nurse colleagues. In contrast, nurses perceive that they have less power than interns and residents, higher-positioned nurses. and staff doctors. Among these groups. nurses perceive that they have the most power over patients and the least over staff doctors. These results indicate that nurses tend to experience more conflicts with members of groups that are stronger than themselves in terms of relative power, Nurses use positive strategies such as the compromise strategy(32.3%) or the collaboration strategy (20.3%) to manage conflicts, more than other strategies. However, they use avoidance or competition strategy more at the earlier stage, compromise strategy more in the mid stage, and collaboration strategy more at the later stage of the interpersonal conflict. In relation to power, nurses use the collaboration strategy or the compromise strategy more when their perceived power is greater than or equal to their counterpart's, and they use the avoidance strategy or the accommodation strategy if their power is less. In terms of source of power, nurses' perceived relative power is greater in the order of referent power. expert power, reward power, legitimate power. and coercive power. where referent power is perceived as having the greatest power and coercive power is least. Most nurses(69.3%) used their power to resolve a conflict. with positive outcomes. Expert power was used most frequently. Overall. this study strongly indicates that the enhancement of power of nurses to have equal power relations with doctors would heighten the success of conflict resolution, since power is the main cause of conflicts. Specifcally. nurses experience most conflicts with doctors against whom they perceive the greatest gap in power. and the choice of a conflict management strategy depend upon their power relations.

• Journal of the Ergonomics Society of Korea
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• v.29 no.5
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• pp.741-750
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• 2010

The objective of this paper is to study if the EEG spectral relative power would be a reasonable measure of expertise level. EEG electrodes were placed on the locations of Fp1, Fp2, F3, F4, T3, T4, O1, O2 while 5 subjects were playing 4 kinds of game on PC. EEG spectral relative power was significantly related with expertise level on the locations of Fp1, T3, T4, O1, O2. And the results showed that the $\theta$ and $\alpha$ activities were decreased, while $\beta$ and $\gamma$ activities were increased. The results indicated that the EEG spectral relative power would be applicable as a quantitative measure of expertise level.

• Nuclear Engineering and Technology
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• v.29 no.5
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• pp.375-384
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• 1997

Relative power density distributions of the Kori Unit 1 pressurized water reactor are calculated by Monte Carlo modeling with the MCNP code. The Kori Unit 1 core is modeled on a three-dimensional representation of the one-eighth of the reactor in-vessel component with reflective boundaries at 0 and 45 degrees. The axial core model is based on half core symmetry and is divided into four axial segments. Fission reaction density in each rod is calculated by following 100 cycles with 5,000 test neutrons in each cycle after starling with a localized neutron source and ten noncontributing settle cycles. Relative assembly power distributions are calculated from fission reaction densities of rods in assembly. After 100 cycle calculations, the system converges to a k value of 1.00039 $\geq$ 0.00084. Relative assembly power distribution is nearly the same with that of the Kori Unit 1 FSAR. Applicability of the full-scope Monte Carlo simulation in the power distribution calculation is examined by the relative root moan square error of 2.159%.

• The Journal of Korean Physical Therapy
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• v.29 no.4
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• pp.164-168
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• 2017

Purpose: Functional electrical stimulation (FES) is a device that activates the sensorimotor cortex through electrodes attached to the surface of the skin. However, it is difficult to expect positive changes if the recipient is not attentive to the motion. To complement the perceived cognitive limitations of FES, we attempted to investigate the changes of sensorimotor cortex activity by simultaneously providing action observation with FES. Methods: Electroencephalogram was measured in 28 healthy volunteers. Relative band power over the sensorimotor cortex was analyzed and compared in three conditions: during rest, during FES alone, during action observation with FES. Results: The results showed significant differences in each relative band power. Relative alpha power and relative beta power were the lowest by application of FES combined with action observation, while the relative gamma power was the highest. Conclusion: These results suggest that combining FES with observation could be more effective than FES alone in neurorehabilitation.

• Journal of Power Electronics
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• v.15 no.3
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• pp.841-848
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• 2015

As a vital part of renewable energy and electrical traction, power converters are supposed to have high reliability and good performance. However, power semiconductors produce considerable heat when the power converter works, which results in high junction temperatures that lower the reliability and performance of the power semiconductors. Many studies show that ambient humidity has a significant effect on power devices, but the influence of high humidity on junction temperatures has yet to be studied. Therefore, this paper presents a thermal model for power converters in moist air to obtain the junction temperature increase, which is utilized for the power converter used in a Switched Reluctance Motor System. Simulation results show that the law of converter temperature distribution is independent of the relative humidity in the case of fixed ambient temperature, whereas the temperature in the power converter decreases as the ambient relative humidity increases. These simulation results are validated with the experimental results.

• Journal of Preventive Medicine and Public Health
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• v.43 no.6
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• pp.543-548
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• 2010

Objectives: The objective of this study was to calculate sample size and power in an ongoing cohort, Korea radiation effect and epidemiology cohort (KREEC). Method: Sample size calculation was performed using PASS 2002 based on Cox regression and Poisson regression models. Person-year was calculated by using data from '1993-1997 Total cancer incidence by sex and age, Seoul' and Korean statistical informative service. Results: With the assumption of relative risk=1.3, exposure:non-exposure=1:2 and power=0.8, sample size calculation was 405 events based on a Cox regression model. When the relative risk was assumed to be 1.5 then number of events was 170. Based on a Poisson regression model, relative risk=1.3, exposure:non-exposure=1:2 and power=0.8 rendered 385 events. Relative risk of 1.5 resulted in a total of 157 events. We calculated person-years (PY) with event numbers and cancer incidence rate in the nonexposure group. Based on a Cox regression model, with relative risk=1.3, exposure:non-exposure=1:2 and power=0.8, 136 245PY was needed to secure the power. In a Poisson regression model, with relative risk=1.3, exposure:non-exposure=1:2 and power=0.8, person-year needed was 129517PY. A total of 1939 cases were identified in KREEC until December 2007. Conclusions: A retrospective power calculation in an ongoing study might be biased by the data. Prospective power calculation should be carried out based on various assumptions prior to the study.

• Journal of Digital Convergence
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• v.14 no.6
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• pp.143-150
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• 2016

This paper's aim is to suggest the Expert System for analyzing relative combat power in ground operations. Since relative combat power analysis in terms of comparing combat power of friendly forces with one of the enemy can determine how the commander and staffs operate their unit afterwards, it requires fast and rational decision-making process. However, it has relied on manual method so far though Tactical Information Communications Network(TICN) into which numbers of applications can be loaded has been developed over a decade. 3 methods for analyzing relative combat power were expressed as mathematic rules to be used knowledge in the expert system after reviewing previous studies, and it studied how intangible power as well as tangible were reflected on total combat power. The expert system that will be built using EXSYS Corvid tool is expected to lessen error rate, provide faster decision-making, and reflect both intangible combat power and tangible one by using an appropriate weights in analyzing relative combat power. Next research filed includes how to build expert systems related with military personnel and intelligence areas for fast and rational decision-making processes.

• Strategy21
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• s.44
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• pp.103-141
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• 2018

As the South China Sea maritime dispute illustrates, when considering the place where maritime claims occur, states do not have many choices to respond to maritime claims in which disputed areas are located far away from the land and are surrounded by the sea. As Mearsheimer (2014) points out, the sea stops power projection. Therefore, in order to adopt coercive as well as peaceful settlement policies to deal with maritime claims, states need to overcome obstacles (the sea) to project power. It means that if states want to conduct a specific foreign policy action, such as negotiating maritime borderlines or arguing sovereignty on islands, they need a tool (naval power) to coerce or to persuade the opponent. However, there are lack of research that studies maritime claims from the perspective of naval power. This research project fills this gap based on naval power. How do relative levels of naval power and (dis) parities of naval power influence the occurrence of MIDs over maritime claims? Naval power is a constitutive element during maritime claims. If disputants over maritime claims have required naval power to project their capability, it means that they have the capability to apply various ways, such as aggressive options including MIDs, to accomplish their goals. So, I argue that when two claimants have enough naval power to project their capabilities, the likelihood of MIDs over maritime claims increases. Given that one or both states have a certain level of naval power, how does relative naval power between two claimants influence the management of maritime claims? Based on the power transition theory, I argue that when the disparities of relative naval power between claimants becomes distinctive, militarized conflicts surrounding maritime territory are less probable. Based on the ICOW project which codes maritime claims from 1900 to 2001, the empirical results of the Poisson models show if both claimants have projectable naval power, the occurrence of MIDs over maritime claims increases. In addition, the result shows that when disputants maintain similar relative naval powers, they are more likely to initiate MIDs over maritime claims. To put it differently, if naval capabilities' gap between two claimants becomes larger, the probability of the occurrence of MIDs decreases.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.3
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• pp.65-75
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• 1998

We consider connection-oriented wireless cellular networks such as the second generation wireless cellular networks and wirelss ATM networks. In these networks, a separate forward signaling channel is provided for the transmission of paging and channel allocation packets. When a call destined to a user is requested, all the base stations in the user's current location area broadcast the corresponding paging packet across forward signaling channels. By slot mode operation and paging group allocation for fusers in a location area, we can reduce relative power consumption level at battery-operated terminals. However, a sthe number of paging groups is increased for lowering relative power consumption level, a paging packet experiences higher delay to access the forward signaling channel. For the pre-negotiated quality-of-service level, paging packet delay level must be limited. In this paper, we consider static and dynamic multiplexing schemes for paging packets, and develop an analytical method for calculating paging packet delay and relative power consumption levels. Using this analytial method, we investigate the effect of network parameters on the paging packet delay and relative power consumption levels.