• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.3
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• pp.264-269
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• 2013

This paper is to investigate propagation path characteristics of GPS potential jamming signal. To do this, the spherical ground diffraction model is applied to the potential jamming scenario referred to the GPS jamming events occurred in recent years. The fundamental theory on the propagation path loss is discussed and a specific model is applied to several vehicles types which have own heights of antennas in order to compare their propagation path loss values at same 2-D location. The transmitting powers are appropriately given as the ordinary GPS jamming events. And then the received powers in dBW are obtained with given transmitting powers and the estimated total loss. The result of received jamming power at various locations due to the given scenario was distinct. For example, propagation loss values were estimated as -147 ~ -142dBW and -167 ~ -162dBW in $10^6W$ and $10^4W$, respectively. This computation result of the loss can be seriously considered with the tolerable jammer power against L1- C/A GPS receiver under any real jamming situations.

• The Journal of Industrial Distribution & Business
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• v.3 no.2
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• pp.5-16
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• 2012

Purpose - Distribution channels cannot function without cooperation. While evidence suggests channel power plays a fundamental role in fostering successful manufacturer-dealer channel cooperation in Western countries distribution systems, little is known empirically as to how dealers' possession of non-mediated powers influence SME manufacturers' cooperation in Asian developing countries. Research design, data, methodology - Drawing upon the extant distribution channels literatures; this study conceptualizes a model and examines the effects of dealer's non-mediated powers on manufacturing SME firms, as well as the mediating influence of trust, relationship satisfaction and commitment. A survey of 400 manufacturing SMEs in Taiwan empirically supports the proposed hypothesis. Results - The model is acceptable in terms of overall goodness of fit. Acceptable model fit are indicated by χ²/(df): 2.35, GFI≧.90; RMSEA values≦ .08; IFI, TLI and CFI values≧.90. Our results indicate that, GFI (0.910), IFI (0.937), TLI (0.903), CFI (0.936), and RMSEA (0.079) and therefore, achieved the suggested thresholds. Conclusions - The results of this study have some managerial implications for managers in the dealer's firms. The overall implication from the findings is that managers can utilize expert, referent and traditional legitimate powers to attain channel cooperation with manufacturing SMEs in addition to garnering their trust, relationship satisfaction and commitment.

• Korean Journal of Remote Sensing
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• v.33 no.1
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• pp.47-60
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• 2017

The permafrost active layer plays an important role in permafrost dynamics. Ecological patterns, processes, and water and ice contents in the active layer are spatially and temporally complex depending on landscape heterogeneity and local-scale variations in hydrological processes. Although there has been emerging interest in the application of optical remote sensing techniques to permafrost environments, optical sensors are significantly limited in accessing information on near surface geo-cryological conditions. The primary objective of this study was to investigate capability of L-band SAR data for monitoring spatio-temporal variability of permafrost ecosystems and underlying soil conditions. This study exploits information from different polarimetric SAR observables in relation to permafrost environmental conditions. Experimental results show that each polarimetric radar observable conveys different information on permafrost environments. In the case of the dual-pol mode, the radar observables consist of two backscattering powers and one correlation coefficient between polarimetric channels. Among them, the dual-pol scattering powers are highly sensitive to freeze/thaw transition and can discriminate grasslands or ponds in thermokarst area from other permafrost ecosystems. However, it is difficult to identify the ground conditions with dual-pol observables. Additional backscattering powers and correlation coefficients obtained from quad-pol mode help understanding seasonal variations ofradar scattering and assessing geo-cryological information on soil layers. In particular, co-pol coherences atHV-basis and circular-basis were found to be very usefultools for mapping and monitoring near surface soil properties.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.17 no.1
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• pp.29-37
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• 1992

In this paper, a new and easy analytical method to get the Fourier transforms of a popular type of truncated raised cosine function and its powers (n=1, 2, :1‥‥ : positive integers) Is proposed. This new. method is based on the concept of the ( 1+D)_type partial response system, and the procedure is more compact than the conventional method using differentiations. Especially, the results are obtained as a sum of three functions which are easily manageable for each power And they are recursively related to their powers. Therefore, they can be excellently applied to the computer-aided numerical solutions.

• International Journal of Reliability and Applications
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• v.7 no.2
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• pp.167-175
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• 2006

Effective and quick methods that are easy to carry out even by hand, or easy to be programmed by hand-held calculators are needed for assessing the sizes of contrasts of unreplicated $2^P$ factorial designs. Moreover, they have the advantage to use the original numerical measurements which makes the analysis easier to explain. Basically, Lenth (1989) is one of the most familiar of such quick and powerful methods. Later on, Aboukalam (2001) proposes under constant effects an alternative sophisticated method to Lenth's method. The proposed method is the supreme from two considerable powers. The first utmost indicates less inflation deficiency while the other utmost indicates less shrinkage deficiency. Also under constant effects, Al-Shiha (2006) introduces an alternative quick method which is less shrinkage deficiency while the inflation deficiency is the same. If effects are random, Aboukalam (2005) introduces an alternative quick method in which the first power is favored as long as the second power is within a small margin. In the spirit of quickness and fixed effects, this article adds another method which is supreme from the two considerable powers. The method is based on a one step of the scale-part of a suggested M-estimate for location. Explicitly, we suggest adapting the skipped median (ASKM) estimate. Critical values of ASKM-method, for several sample sizes often used, are empirically computed.

• Journal of Contemporary Eastern Asia
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• v.20 no.2
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• pp.157-173
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• 2021

In the transition to a multipolar international system, the literature has focused on great power competition while little attention has been given to the strategic possibilities of smaller states. However, as a result of globalization, states are so closely interconnected that the primary strategies of even major powers are not to achieve zero-sum solutions but to create asymmetric dependency through which they can influence the behavior of other states and non-state actors. States are assisted in this effort by a variety of tools, including setting up institutions, direct economic influence and through building different forms of infrastructure connectivity networks. By discussing asymmetric dependency situations from the perspective of the great powers, the literature presents smaller states primarily as passive actors, paralyzed by their dependence on great powers. Our paper argues that interdependence allows smaller states to effectively influence larger actors and examines strategies from which smaller states can choose in order to influence the behavior of larger states. Despite an extremely asymmetric relationship between Myanmar and China, actors in Myanmar have sought to influence China's Myanmar policy. We examine a case study of the Myitsone Dam, including Myanmar's strategic aims, chosen strategy and limitations in maneuvering space. Semi-structured interviews with local decision-makers and stakeholders are conducted in order to portray the full picture. Our study concludes that further research on the influencing strategies of small states in response to asymmetric dependence can contribute to a better understanding of the interdependence of states.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.2
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• pp.231-237
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• 2014

Purpose: This study is research of the conditions which causes difference between the refractive power of the measurement of autorefractometer and the prescription using phoropter. Methods: Autorefractometer (SR-7000) and phoroptor (AV-9000) were used to measure 60 eyes of 30 participants who had no eye diseases and wore the corrective lens due to Ametropia. To prevent the dependence of the prescription value of the refractive power on the testers, two testers measured the refractive power of the eyes of the participants at the same measuring conditions. Results: Statistically, the prescribed values of the refractive power by two testers were not significantly different. Most of the prescribed values of the refractive power were smaller than the refractive power by autorefractometer In case of myopic eyes, the difference between refractive powers by the measurement of autorefractometer and the prescription using phoropter showed the trend of increase as the spherical refractive power became larger. The result was analyzed by the range of the different cylindrical refractive power for the myopic astigmatic eyes. In this case, the difference between refractive powers showed the trend of decrease as the cylindrical refractive power became larger. Conclusions: No difference between the prescribed value by two testers was observed. In case of myopic or myopic astigmatic eyes, the difference between refractive powers by autorefractometer and the prescription were measured to be approximately proportional to the refractive powers of ametropic eyes. As the this difference become larger for the participant who needs the lens of larger refractive power, additional caution is needed in the prescription of the refractive power of the corrective lens.

• Journal of Life Science
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• v.19 no.12
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• pp.1829-1835
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• 2009

Hyperventilation (HV) is routinely induced in order to activate brain waves during an electroencephalogram (EEG). The aim of this study was to examine the effects of HV conditions on EEG and suggested basic data for the standardized procedure. Three degrees of HV were induced for 5 minutes with a ventilation volume of 160 ml/min (control group), 240 ml/min, and 300 ml/min in rats. Powers of delta, theta, alpha, and beta waves were examined by a quantitative EEG. The results showed that there was no significant difference in the powers of all EEG waves between the control and 240 ml/min groups. However, a notable change in EEG powers during HV induced by a ventilation volume of 300 ml/min was observed in the frontal cerebral region as follows: power of the delta was increased by 12.8% (p<0.01), powers of the theta, alpha and beta were decreased by 41.3% (p<0.01), 48.6% (p<0.05), and 41.9% (p<0.05), respectively. Therefore, it is concluded that an increase of about 90% of the normal ventilation volume might be adequate for the hyperventilation, and a useful parameter for evaluation of the qualified hyperventilation might be an alteration of the frontal EEG powers.

• Communications of the Korean Mathematical Society
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• v.5 no.2
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• pp.147-149
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• 1990

• Proceedings of the Korean Magnestics Society Conference
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• 1999.04a
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• pp.110-111
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• 1999