• Journal of Astronomy and Space Sciences
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• v.39 no.1
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• pp.11-22
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• 2022

It is suggested that magnetosonic waves (also known as equatorial noise) can scatter radiation belt electrons in the Earth's magnetosphere. Therefore, it is important to understand the global distribution of these waves between the proton cyclotron frequency and the lower hybrid resonance frequency. In this study, we developed an empirical model for estimating the global distribution of magnetosonic wave amplitudes and wave normal angles. The model is based on the entire mission period (approximately 2012-2019) of observations of Van Allen Probes A and B as a function of the distance from the Earth (denoted by L^*), magnetic local time (MLT), magnetic latitude (λ), and geomagnetic activity (denoted by the Kp index). In previous studies the wave distribution inside and outside the plasmasphere were separately investigated and modeled. Our model, on the other hand, identifies the wave distribution along with the ambient plasma environment-defined by the ratio of the plasma frequency (f_pe) to the electron cyclotron frequency (f_ce)-without separately determining the wave distribution according to the plasmapause location. The model results show that, as Kp increases, the dayside wave amplitude in the equatorial region intensifies. It thereby propagates the intense region towards the wider MLT and inward to L^* < 4. In contrast, the f_pe/f_ce ratio decreases with increasing Kp for all regions. Nevertheless, the decreasing aspect differs between regions above and below L^* = 4. This finding implies that the particle energy and pitch angle that magnetosonic waves can effectively scatter vary depending on the locations and geomagnetic activity. Our model agrees with the statistically observed wave distribution and ambient plasma environment with a coefficient of determination of > 0.9. The model is valid in all MLTs, 2 ≤ L^* < 6, |λ| < 20°, and Kp ≤ 6.

• Journal of the Chungcheong Mathematical Society
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• v.27 no.2
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• pp.243-247
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• 2014

Let {$X_n$, $n{\geq}1$} be a sequence of i.i.d. random variables with absolutely continuous cumulative distribution function(cdf) F(x) and the corresponding probability density function(pdf) f(x). In this paper, we give characterizations of Pareto and Weibull distribution by considering conditional expectations of record values.

• Journal of the Chungcheong Mathematical Society
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• v.22 no.2
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• pp.149-153
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• 2009

Let {$X_{n},\;n\;\geq\;1$} be a sequence of independent and identically distributed random variables with absolutely continuous cumulative distribution function (cdf) F(x) and probability density function (pdf) f(x). Suppose $X_{U(m)},\;m = 1,\;2,\;{\cdots}$ be the upper record values of {$X_{n},\;n\;\geq\;1$}. It is shown that the linearity of the conditional expectation of $X_{U(n+2)}$ given $X_{U(n)}$ characterizes the lomax, exponential and pareto distributions.

• Journal of the Korean Mathematical Society
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• v.32 no.2
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• pp.279-287
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• 1995

Let $F$ be a set of distributions on R with the topology of weak convergence, and let $A$ be the $\sigma$-field generated by the open sets. We denote by $F_1^\infty$ the space consisting of all infinite sequence $(F_1, F_2, \cdots), F_n \in F and R_1^\infty$ the space consisting of all infinite sequences $(x_1, x_2, \cdots)$ of real numbers. Take the $\sigma$-field $F_1^\infty$ to be the smallest $\sigma$-field of subsets of $F_1^\infty$ containing all finite-dimensional rectangles and take $B_1^\infty$ to be the Borel $\sigma$-field $R_1^\infty$.

• Bulletin of the Korean Chemical Society
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• v.23 no.2
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• pp.229-240
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• 2002

Quantum mechanical calculation is performed for the $O(^1D)$ + HCl ${\rightarrow}$OH + Cl reaction using Reactive Infinite Order Sudden Approximation. Shifting approximation is also employed for the l ${\neq}$ 0 partial wave contributions. Various dynamical quantities are calculated and compared with available experimental results and quasiclassical trajectory results. Vibrational distributions agree well with experimental results i.e. product states mostly populated at $v_f$ = 3, 4. Our results also show small peak at $v_f$ = 0, which indicates bimodal vibrational distribution. The results show two significant broad peaks in ${\gamma}_i$ dependence of the cross section, one is at ${\gamma}_i$ = $15^{\circ}-35^{\circ}$ and the another is at ${\gamma}_i$= $55^{\circ}-75^{\circ}$ which can be explained as steric effects. At smaller gi, the distribution is peaked only at higher state ($v_f$ = 3, 4) while at the larger gi, both lower state ($v_f$ = 0) and higher state ($v_f$ = 3, 4) are significantly populated. Such two competing contributions (smaller and larger ${\gamma}_i$) result in the bimodal distribution. From these points we suggest two mechanisms underlying in current reaction system: one is that reaction occurs in a direct way, while the another is that reaction occurs in a indirect way.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.4 s.152
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• pp.615-622
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• 2006

A tool to evaluate the subjective wearing comfort of caps from the objective measurement of pressure was developed. Comfortable Fittability Index(C.F.I) and Holding Power(HP) were defined to represent the subjective wearing comfort of caps. As a preliminary step to define the Comfortable Fittability Index(C.F.I), average pressure, pressure distribution, standard deviation of pressure were obtained and subjective sensation were evaluated by wearing caps. Also Holding Power(HP) was estimated from wind tunnel testing. Two sets of caps were evaluated, one set made of elastic fabric(F-caps) and the other set made of non-elastic fabric(S-caps). F-caps begin to be taken off by the higher wind velocity and thus exhibited higher values of Holding Power. On the other hand, F-caps exerted lower average pressure, narrower pressure distribution, smaller standard deviation.

• Journal of Power System Engineering
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• v.18 no.6
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• pp.70-76
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• 2014

Surely fuel economy(F.E.) label is needed to meet consumer's right to know. Korea has developed and adopted F.E. correction equation similar to the feeling, because consumer complain about F.E. label higher than they feel. Recently, through continuous research and development high-efficiency & performance green car like HEV, PHEV and EV are being sold. In this situation, it is needed to know whether the current equation can reflect a part of their improved technic or not. In this paper, to review current equation through test using hybrid vehicles on 5-cycle SOC, correction equation and F.E were discussed. The result show HEV didn't meet the SOC error standard on US06. Also, HEV has bigger F.E. difference between FTP-75 and 5-cycle than conventional vehicles. However, the correction equation that include HEV almost same with current one.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.12
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• pp.5518-5524
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• 2011

The purpose of this study is to investigate the change of balance ability on aging by measuring balance ability of elderly females whose age is over 65. The subjects are ten elderly women (the mean age: 71.9) able to walk without assistants, the assistant equipments and drug dependence and ten young healthy women (the mean age: 23.2). We measured stability index (ST), Fourier index (F), weight distribution (WD), weight distribution index (WDI), synchronization index (SI) and fall index (FI) by using Tetrax (Tetra-ataxiometric Posturography). In result, STs and Fs at the low frequency region (F1) represented the significant difference between two groups at all postures with PO (pillow with eye open) exception (p<.01). Fs at the other frequency regions (F2~F8) represented the significant difference between two groups (p<.05). WDI of the elderly women represented the higher values than the young women at all postures but there are the significant difference at PO and PC (pillow with eye closed) only. These results may be due to age-related ability decline of somatesthesia, vestibular organ, central nervous system.

• The Plant Pathology Journal
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• v.39 no.6
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• pp.575-583
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• 2023

Fusarium root rot is an increasingly severe problem in soybean cultivation. Although several Fusarium species have been reported to infect soybean roots in Heilongjiang province, their frequency and aggressiveness have not been systematically quantified in the region. This study aimed to investigate the diversity and distribution of Fusarium species that cause soybean root rot in Heilongjiang province over two years. A total of 485 isolates belonging to nine Fusarium species were identified, with F. oxysporum and F. solani being the most prevalent. Pot experiments were conducted to examine the relative aggressiveness of different Fusarium species on soybean roots, revealing that F. oxysporum and F. solani were the most aggressive pathogens, causing the most severe root rot symptoms. The study also assessed the susceptibility of different soybean cultivars to Fusarium root rot caused by F. oxysporum and F. solani. The results indicated that the soybean cultivar DN51 exhibited the most resistance to both pathogens, indicating that it may possess genetic traits that make it less susceptible to Fusarium root rot. These findings provide valuable insights into the diversity and distribution of Fusarium species that cause soybean root rot and could facilitate the development of effective management strategies for this disease.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.24 no.1
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• pp.67-75
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• 2018

Background: The purpose of this study was to investigate the effect of pressure distribution on the both foots with gluteus medius muscle intensive strengthening exercise in 4week. Methods: The purpose of this study was to investigate the effect of gluteus medius muscles strengthening exercise on the pressure distribution of the foot in 20 healthy adults. Four gluteus medius muscles strengthening exercise programs were conducted three times a week for four weeks. The pressure distribution changed of the right and left foot parts of the experimental group and the control group were measured and analyzed. Results: There was a significant difference in F1, F2, M1, M2, and H1 among the pressure distribution of the right foot of the experimental group (p<.05). There was a significant difference in F1, M1, M2, H1 and H2 among the pressure distributions of the left foot of the experimental group (p<.05). There was a significant difference in H1 among the pressure distribution of the right foot of the control group (p<.05). There was no significant difference in the pressure distribution of the left foot region of the control group (p>.05). There was a significant difference in H1 among the pressure distribution of the right foot between the group (p<.05). There was a significant difference in M2, H1 among the pressure distribution of the left foot between the group (p<.05). Conclusions: In the healthy adults, it was confirmed that the application of the gluteus medius muscles strengthening exercise had an effect on the weight shift during the walking due to the overall foot balance and the pressure distribution change of the foot part.