• Journal of the Korean Mathematical Society
• /
• v.46 no.5
• /
• pp.1087-1103
• /
• 2009

Given a system of s independent 1-forms on a smooth manifold M of dimension m, we study the existence of integral manifolds by means of various generalized versions of the Frobenius theorem. In particular, we present necessary and sufficient conditions for there to exist s'-parameter (s' < s) family of integral manifolds of dimension p := m-s, and a necessary and sufficient condition for there to exist integral manifolds of dimension p', p' $\leq$ p. We also present examples and applications to complex analysis in several variables.

• Journal of Applied and Pure Mathematics
• /
• v.4 no.1_2
• /
• pp.79-84
• /
• 2022

We have observed that there exist certain fuzzy topological spaces with no fuzzy minimal open sets. This observation motivates us to investigate fuzzy topological spaces with neither fuzzy minimal open sets nor fuzzy maximal open sets. We have observed if such fuzzy topological spaces exist and if it is connected are not fuzzy cut-point spaces. We also study and characterize certain properties of fuzzy mean open sets in fuzzy T₁-connected fuzzy topological spaces.

• Proceedings of the Korea Society for Simulation Conference
• /
• 2001.10a
• /
• pp.37-43
• /
• 2001

New product development has been a key element fur organizational evolution. The bulk of research about new product strategy has focused solely on new product development function itself. This paper investigates cross-functional elements in new product development. More specifically, we suggest that there must exist a fit between new product strategy and value chain strategy. It means that, in order to support new product development activity, there must exist a relevant value chain strategy. We consider three types of integration - internal integration, customer integration, and supplier integration - as strategic elements of value chain strategy. For the case of new product strategy, we consider market newness and product technology unfamiliarity as strategic elements. We also consider two types of learning characteristic, i.e., \\\"fast-adaptive learning\\\" and \\\"slow-adaptive leaning\\\" as control factor. Learning characteristic represents firms organizational capability related with organizational learning. For example, fur fast-adaptive learning case, the effect of integration appears early in time. System dynamics simulation is employed to verify our research framework. The results exhibit that there must exist cross-functional relationships between value chain strategy and new product strategy in order to shorten total development time.al development time.

• Journal of Broadcast Engineering
• /
• v.14 no.1
• /
• pp.70-80
• /
• 2009

We propose an ideal line coding for high speed data communication in visible light communication system. B4-HBT line coding is defined as follow. The 1 bit is +V at first though 1 encodes +Voltage and -Voltage doing change of shift each other, then -V newly. V that is been mutually contradictory for 1 bit that exist before that if continuous 0 bits exist 4 here same and reduces mistake because has reverse mark V in 4 continuous last 0 bits and gives half bit variation in 1 bit and made effect of noise low. 2${\sim}$3 dB profit is seen comparing with line coding that exist in simulation result.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.14 no.1
• /
• pp.121-133
• /
• 2018

The goal of this study is to investigate the factors affecting firefighter's traumatic experiences and to examine and compare the differences of how those factors contribute to firefighter's burnout, depression, anxiety and social relationships. This study suggests that it is imperative for firefighters to have mindfulness, which brings mental and emotional healing, for their job-satisfaction. To empirically examine the research model of this study, the questionnaire survey was carried out to firefighters in InCheon Metropolitan City for two weeks; from October 19thto November 3rd, 2017. Out of 180 questionnaires, 170were retrieved. Total number of 160 questionnaires are empirically examined this study, excluding10bad survey responses. The t-test was conducted to determine whether there exist differences by gender among traumatic experienced firefighters, and a meaningful difference was found from perceived intrusiveness, a sub factor to traumatic experiences. Male firefighters showed higher mean than that of female firefighters in perceived angle, evasion and intrusiveness. Second, the t-test was conducted to determine whether there exist differences by gender in firefighter's burnout, but no meaningful differences were found. Female firefighters showed higher mean in emotional exhaustion, impersonalization and in decrease in self-achievements. Third, the t-test was conducted to determine whether there exist differences by gender in firefighter's depression and relationships, but no meaningful differences were found.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.14 no.24
• /
• pp.123-132
• /
• 1991

This study deals with the experiment of perceiving visual information according to the positions of vehicle side mirrors. In the design of vehicle, the consideration of safety is very important. Therefore we consider the positions of side mirrors to use visual information effectively which is important factor to driver. This paper presents the position of side mirror to elevate the degree of visual perception for the circumstances of danger by experiments. To exhibit the circumstances of danger. 4 LED(Light Emitted Diode) art located at each side(right. left front. hack) of vehicle. A subject pushes the LED switch to see that if he perceives the circumstance of danger. To record the circumstance of randomly generated danger, computer interface card is used to control 4 LED and swithch on IBM PC/AT Experiments are divided into 2 parts. The 1st experiment present the independence of right & left side mirror. The 2nd experiment present optimal position of right & left side mirror. The vehicle used in experiment is model EL of H Co.. Statistical process of experimental data using SPSS(Statistical Package for Social Sciences)/PC package concludes that 1) the optimal position of right side mirror is 54cm forward of exist position. 2) for the left side mirror, the position of 120cm forward of exist position shows the worst degree of perception. and the optimal position does not exist in statistical meaning.

• The Research Journal of the Costume Culture
• /
• v.27 no.3
• /
• pp.264-273
• /
• 2019

Fashion as a field of cultural studies is a very complex field that is very interesting to discuss, especially in Indonesia as the very rich country in cultures and past traditions. This research will discuss the development of fashion in Bali, one area that is opulent in its cultures. Based on the research conducted by today's fashion development, Bali is still strongly influenced by factors inherited from traditional values that exist in the Balinese culture. This research is conducted by applying the qualitative method with the ethnography approach to unravel any factor in Bali so that it becomes the foundation and triggers the rapid development of fashion by still maintaining the values of the tradition. Considering that the values of tradition as a whole have a good impact on the preservation of the natural balance and various factors that exist in society, whether these factors still exist in other regions of Indonesia and they are possible to be developed in various regions of Indonesia. So hopefully the development of fashion in Indonesia as a whole can maintain the local content that characterizes the Indonesian Nation and have a positive impact on the balance of nature and also to the community in Indonesia and the world culture.

• Bulletin of the Korean Mathematical Society
• /
• v.26 no.2
• /
• pp.191-201
• /
• 1989

In this article we are interested in characterizing when metric projection is Lipschitz continuous and determining when metric selections which are also Lipschitz continuous exist.

• Bulletin of the Korean Chemical Society
• /
• v.19 no.3
• /
• pp.375-378
• /
• 1998

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.9 no.3
• /
• pp.107-117
• /
• 2013

In this paper, we designed the security management system based on IEC 62351-7 in the Smart Grid environment. The scope of IEC 62351-7 focuses on network and system management (NSM) of the information infrastructure as well as end-to-end security through abstract NSM data objects for the power system operational environment. However, it does not exist that security management system based on IEC 62351-7 manages the security of the power system in the Smart Grid environment, because power equipment or SNMP agents providing NSM data do not exist yet. Therefore, we implemented the security management system to manage the information infrastructure as reliably as the power system infrastructure is managed. We expect that this system can perform the security management of IEC 61850 based digital substation and can be a prototype of the security system for the Smart Grid in the future.