• Communications of the Korean Mathematical Society
• /
• v.19 no.4
• /
• pp.731-743
• /
• 2004

Harmonic distribution is the distribution which has the minimal value of functional called energy. In this paper it is shown as a specific distribution of semisimple Lie group whose manifold is compact.

• Agribusiness and Information Management
• /
• v.6 no.2
• /
• pp.13-23
• /
• 2014

The world is in the process of a structural change related to ICT convergence knowledge industries. ICT is leading to the creation of new products and services, and is making our lives more convenient, safer, and more efficient. In advanced countries, many studies have been conducted with the goal of developing new business models converged with ICT, and this is also the case in the food industry. Korea possesses world-leading ICT, and if this ICT is applied to the food industry, a world-class new business model can be developed. The u-Food System, which is in the process of development in Korea, is a next-generation food system that can allow food providers, consumers, and distributors to access various types of information about food products, including traceability, distribution, safety, quality, and freshness, and manage this information. It is a future food system that converges ICT, biotechnology and sensing technology with food. Based on the u-Food System, this paper will introduce the status of current smart quality distribution technologies that converge ICT (such as sensor tag, sensor network, LBS, GIS, and CDMA) with food technologies (such as traceability, quality, distribution management) to manage the safety and quality of fresh food in the distribution process.

• Fire Science and Engineering
• /
• v.30 no.2
• /
• pp.62-67
• /
• 2016

In this study, the optical depth is analyzed with the effects of droplet size distribution of the water curtain nozzle to attenuate the radiative heat transfer. The HELOS/VARIO equipment is used for the measurement of the droplet size distributions. The spray characteristics are quantified by the investigation of Deirmenjian's modified gamma distribution function. The distribution constant of the nozzle can be obtained as ${\alpha}=1$ and ${\gamma}=5.2$. The generalized equation of the optical depth related with the droplet size distribution is introduced. These results will be applicable to the analysis of the design condition of the water curtain nozzle.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.61 no.4
• /
• pp.513-521
• /
• 2012

With the advent of smart grid, distribution network charges have been one of keystones of ongoing deregulation and privatization in power industries. This paper proposes a new charging methodology to allocate the existing distribution network cost with an aim of reflecting the true cost and benefit of network customers, especially of distribution generator (DG). The proposed charging methodology separates distribution network costs due to the respective real and reactive power flows. The costs are then allocated to network users according to each charge for the actual line capacity used and available capacity. This distribution network charging model is able to provide the economic signals to reward network users who are contributing to better power factors, while penalizing customers who worsen power factors. The proposed method is shown on IEEE 37 bus system for distribution network, and then the results are validated through the comparison with the MW-Miles and MVA-Miles methods. The charges derived from the proposed method can provide appropriate incentives/penalties to network customers to behave in a manner leading to a better network condition.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.25 no.5
• /
• pp.369-375
• /
• 2020

Distribution energy resources have been increasing in recent years. However, output power is limited for distribution network stability. This study proposes an active distribution network that can reconfigure distribution lines by using an active phase controller. A conventional distribution network has a fixed structure, whereas an active distribution network has a variable structure. Therefore, the latter can increase the output power of distribution energy resources and decrease the overload of distribution line facilities. An active phase controller has two operation modes for minimizing circulating current during dynamic reconfiguration. In this study, voltage and current control algorithms are proposed for active phase controllers. The simulation of the proposed methods for active phase controllers is performed using PSIM software.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.66 no.3
• /
• pp.500-506
• /
• 2017

In 2014, ISO 55000s has been enacted and the power plant asset management is becoming a hot issue for all over the world. The asset management system is being developed as a combination of CBM(Condition Based Maintenance) and RCM(Reliability Centered Maintenance). Therefore, the research on the calculation of the failure rate which is the most basic index of RCM is actively carried out. The failure rate calculation has been going on for a long time, and the most widely used probability distribution is the Weibull distribution. In the Weibull distribution, the failure rate function is determined in three types according to the value of the shape parameter. However, the Weibull distribution has a limitation that it is difficult to apply it when the trend of failure rate changes-such as bathtub curves. In this paper, the failure rate is calculated using the mixture Weibull distribution which can appropriately express the change of the shape of the failure rate. Based on these results, we propose the necessity and validity of applying mixture Weibull distribution.

• Structural Engineering and Mechanics
• /
• v.80 no.5
• /
• pp.523-538
• /
• 2021

The mechanical behaviour and stability of coal mining engineering underground is significantly affected by ground water. In this study, nuclear magnetic resonance imaging (NMRI) technique was employed to determine the water distribution characteristics in coal specimens during saturation process, based on which the functional rule for water distribution was proposed. Then, using discrete element method (DEM), an innovative numerical modelling method was developed to simulate water-weakening effect on coal behaviour considering moisture content and water distribution. Three water distribution numerical models, namely surface-wetting model, core-wetting model and uniform-wetting model, were established to explore the water distribution influences. The feasibility and validity of the surface-wetting model were further demonstrated by comparing the simulation results with laboratory results. The investigation reveals that coal mechanical properties are affected by both water saturation coefficient and water distribution condition. For all water distribution models, micro-cracks always initiate and nucleate in the water-rich area and thus lead to distinct macro fracture characteristics. With the increase of water saturation coefficient, the failure of coal tends to be less violent with less cracks and ejected fragments. In addition, the core-wetting specimen is more sensitive to water than specimens with other water distribution models.

• Anatomy and Cell Biology
• /
• v.55 no.2
• /
• pp.190-204
• /
• 2022

The anti-aging effects of Lactococcus lactis are extensively investigated. Nisin is an antimicrobial peptide produced by L. lactis subsp. lactis. We previously reported that 24-hour nisin treatment disturbs the intermediate filament distribution in human keratinocytes. Additionally, we showed that the ring-like distribution of the intermediate filament proteins, cytokeratin (CK) 5 and CK17 is a marker of nisin action. However, two questions remained unanswered: 1) What do the CK5 and CK17 ring-like distributions indicate? 2) Is nisin ineffective under the experimental conditions wherein CK5 and CK17 do not exhibit a ring-like distribution? Super resolution microscopy revealed that nisin treatment altered CK5 and CK17 distribution, making them spherical rather than ring-like, along with actin incorporation. This spherical distribution was not induced by the suppression of endocytosis. The possibility of a macropinocytosis-like phenomenon was indicated, because the spherical distribution was >1 ㎛ in diameter and the spherical distribution was suppressed by macropinocytosis inhibiting conditions, such as the inclusion of an actin polymerization inhibitor and cell migration. Even when the spherical distribution of CK5 and CK17 was not induced, nisin induced derangement of the cell membrane. Nisin treatment for 30 minutes deranged the regular arrangement of the lipid layer (flip-flop); the transmembrane structure of the CK5-desmosome or CK17-desmosome protein complex was disturbed. To the best of our knowledge, this is the first study to report that CK5 and CK17 in a spherical distribution could be involved in a macropinosome-like structure, under certain conditions of nisin action in keratinocytes.

• Journal of Fashion Business
• /
• v.20 no.1
• /
• pp.1-16
• /
• 2016

Korean cosmetic distribution channels were formerly divided into sales visits and specialty shops, which made up the entire cosmetics market. However, recently the market and cosmetic distribution channels have become much more diversified. Thus, research for this study focused on the usage and purchase situations of cosmetic distribution channels depending on cosmetic type perception. This study also focused on the intent to purchase cosmetics by a cosmetic distribution channel in order to provide a precise cognitive background of consumers regarding cosmetic distribution channels. In doing so, the competitiveness of those channels could be procured and the causal relationships between these variables can be investigated. To achieve these purposes, the research model and hypotheses were derived through literature research on the cosmetics industry, cosmetic distribution channels, and consumers' intent to purchase. A survey was implemented from September $1^{st}$ to $14^{th}$, 2014 for empirical testing. and was given to female consumers in their 20s. 468 out of 500 surveys were collected; a total of 415 were used for analysis while the others were excluded due to with unreliable responses. The SPSS 21.0 program was used for analysis of materials. The overall conclusion of this study is that there is a relationship between perception of cosmetic distribution channels and intent to purchase. The above research results may stimulate establishment of marketing implications and research material when establishing marketing strategies to promote cosmetic distribution and consumption.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.34 no.4
• /
• pp.185-204
• /
• 2009

The USIM(universal subscriber identity module)-unlock introducing in July 1, 2008 might be led to a significant change that mobile service provider's dominance is considerably dispersed to the handset manufacturer and distributor. Under USIM-unlock environment, mobile service provider, handset manufacturer, and distributor have to make their decisions on their handset distribution channel strategies: the closed distribution channel strategy or the open distribution channel strategy. The change of distribution channel strategy between members in distribution channel can be understood as a matter of strategy choice, and we have developed a theoretical model and analyzed how to make a decision for the member's optimal distribution strategy based on 3-person game model between members of mobile phone distribution channel, under both of '1 subscriber-1 handset' and '1 subscriber-multiple handset' assumptions. Under '1 subscriber-1 handset' assumption, the closed strategy controlled by mobile service provider is all players' optimal solution because the maximum size of the mobile phone market is limited by subscribers. But, as total expected profit by the handset and distribution subsides is a deficit, mobile service provider have to choose the open strategy and consider the conversion to MNO(mobile network operator). Under '1 subscriber-multiple handset' assumption, mobile service provider is trying to find the way how to lock-in its service and mobile phone and how to maximize ARPU(average revenue per unit), while handset manufacturer and distributor have to look for the way how to maximize the mobile phone market using their own marketing efforts, because it is expected that total mobile handset demand for the open market is bigger than demand for the closed market under '1 subscriber-multiple handset' assumption.