• Bulletin of the Korean Mathematical Society
• /
• v.60 no.4
• /
• pp.1017-1024
• /
• 2023

A celebrated result in the study of integer partitions is the identity due to Lehmer whereby the number of partitions of n with an even number of even parts minus the number of partitions of n with an odd number of even parts equals the number of partitions of n into distinct odd parts. Inspired by Lehmer's identity, we prove explicit formulas for evaluating generating functions for sequences that enumerate integer partitions of fixed width with an even/odd number of even parts. We introduce a technique for decomposing the even entries of a partition in such a way so as to evaluate, using a finite sum over q-binomial coefficients, the generating function for the sequence of partitions with an even number of even parts of fixed, odd width, and similarly for the other families of fixed-width partitions that we introduce.

• Journal of Genetic Medicine
• /
• v.9 no.2
• /
• pp.101-103
• /
• 2012

Paracentric inversion of chromosome 18 is a rare cytogenetic abnormality. The vast majority of paracentric inversions are harmless and the offspring of paracentric inversion carriers have only slightly elevated risks for unbalanced karyotypes. However, various clinical phenotypes are seen due to breakpoint variation or recombination. We report a prenatally detected case of familial paracentric inversion of chromosome 18, inv(18)(q21.1q22), with normal clinical features.

• Journal of Korea Multimedia Society
• /
• v.21 no.2
• /
• pp.188-198
• /
• 2018

With recent development of high-speed wide-area wireless networks and wide spread of highperformance wireless devices, the demand on seamless video streaming services in Long Term Evolution (LTE) network environments is ever increasing. To meet the demand and provide enhanced Quality of Experience (QoE) with mobile users, the Dynamic Adaptive Streaming over HTTP (DASH) has been actively studied to achieve QoE enhanced video streaming service in dynamic network environments. However, the existing DASH algorithm to select the quality of requesting video segments is based on a procedural algorithm so that it reveals a limitation to adapt its performance to dynamic network situations. To overcome this limitation this paper proposes a novel quality selection mechanism based on a Deep Q-Network (DQN) model, the DQN-based DASH ABR($DQN_{ABR}$) mechanism. The $DQN_{ABR}$ mechanism replaces the existing DASH ABR algorithm with an intelligent deep learning model which optimizes service quality to mobile users through reinforcement learning. Compared to the existing approaches, the experimental analysis shows that the proposed solution outperforms in terms of adapting to dynamic wireless network situations and improving QoE experience of end users.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.19 no.6
• /
• pp.1499-1505
• /
• 2015

This study is about the patent information analysis of relevant companies and technologies based on International Patent Classification (IPC) code. 902 patent applications in the field of electronic commerce(G06Q) by NAVER, the biggest internet company in Korea, are the subjects of this study. First, we investigated the number of applications and registrations per IPC code so that we could analyze the core technology areas and the status of patent application. In addition, we examined the convergence of technologies by investigating interconnections between main and sub categories of IPC codes. Lastly, we looked into the changes in patent technologies by investigating the status of application per IPC code in accordance with year. By analyzing the IPC code based patent information used in this study, we could further expect the trends of companies and technologies.

• Journal of Electrical Engineering and Technology
• /
• v.10 no.2
• /
• pp.504-510
• /
• 2015

Because wind generators (WGs) in a wind power plant (WPP) produce different active powers due to wake effects, the reactive power capability of each WG is different. This paper proposes a hierarchical voltage control scheme for a WPP that uses a WPP controller and WG controller. In the proposed scheme, the WPP controller determines a voltage error signal by using a PI controller and sends it to a doubly-fed induction generator (DFIG). Based on the reactive current-voltage ($I_Q-V$) characteristic of a DFIG, the DFIG injects an appropriate reactive power corresponding to the voltage error signal. To enhance the voltage recovery capability, the gains of the $I_Q-V$ characteristic of a DFIG are modified depending on its reactive current capability so that a DFIG with greater reactive current capability may inject more reactive power. The proposed scheme enables the WPP to recover the voltage at the point of common coupling (PCC) to the nominal value within a short time after a disturbance by using the adaptive $I_Q-V$ characteristics of a DFIG. The performance of the proposed scheme was investigated for a 100 MW WPP consisting of 20 units of 5 MW DFIGs for small and larger disturbances. The results show the proposed scheme successfully recovers the PCC voltage within a short time after a disturbance.

• Applied Biological Chemistry
• /
• v.45 no.4
• /
• pp.190-194
• /
• 2002

Expression of Bacillus subtilis glutamyl-tRNA synthetase (GluRS) in Escherichia coli is lethal for the host, probably because this enzyme misaminoacylates ${tRNA_l}^{Gln}$ with glutamate in vivo. In order to overexpress B. subtilis GluRS, encoded by the gltX gene, in E. coli, this gene was amplified from B. subtilis 168 chromosomal DNA using PCR method and the entire coding region was cloned into a pET11a expression vector so that it was expressed under the control or the T7 Promoter. The resulting recombinant pEBER plasmid was transformed into E. coli Novablue (DE3) bearing the T7 RNA polymerase gene for expression. After IPTG treatment, the overproduced enzyme was purified using ammonium sulfate fractionation, Source Q anion exchange chromatography, Superdex-200 gel filtration, and Mono Q anion exchange chromatography. The purified enzyme yielded 18-fold increase in specific activity over the crude cell extract and its molecular weight was approximately 55 kDa on SDS-PAGE.

• The Journal of the Korea Contents Association
• /
• v.20 no.10
• /
• pp.522-534
• /
• 2020

The purpose of this study is to suggest practical ways to improve the 5th Government Employees Pension System(GEPS) in the near future. This article surveyed the civil servants cognition in three different levels(validity, feasibility, efficiency) by Q methodology. The value and mean of GEPS in the validity level, procedure and participants of GEPS reform process in the feasibility level, and contribution rates, benefit rate, replacement rate of GEPS in the efficiency level were analyzed. There is no successful policy without securing compliance and acceptance of implementation organization and target group. So next 5th GEPS reform could proceed successfully when it took into account civil servant's-who is the implementation group and target group- thought about variances of the 3 levels of GEPS.

• Journal of Korean Academy of Nursing
• /
• v.28 no.4
• /
• pp.992-1002
• /
• 1998

This study measures the subjectivity(opinions·attitudes)of college women. Identifying the schemata(structure of subjectivity) would be a basic step for the women's health education and the promotion to alternative strategies of women's health nursing. More concretely, these following research questions are focused. 1) The subjective schemata : find out typologies based on the opinions and attitudes toward the health lifestyle. 2) Applications : describe the characteristics of each type. 3) Alternatives : provide suggestion of the promotion to alternative strategies for women's health nursing. Q- Methodological method was used for that purpose. As for the research method, Q-statements were preliminary collected in the study from through in-depth interviews and a literature review. For the study 36 Q-statements were selected. 33 college women were used as subjects for research. The 33 college women sorted the 36 statements using the principle of Forced Normal Distribution. The principle of Forced Normal Distribution, which has nine scales to measure the individual opinions, was called. Q-Factor Analysis by using PC Quanl Program to supply the material. According to the outcomes of this study, there were three categories of special opinions about the health lifestyle in college women. The first type is called Initiatived Health Management Type. The second type is called Social Activity Centered Type. The third type is called Positive Outlook Type. Through the result of this study, the health lifestyle could be identified by 3 types, therefore the nurses needed to understand each women's meaning to health lifestyle so they could develop the appropriate nursing intervention based the typology of the health lifestyle this study explored. Finally, The result of the study will provide clues for developing a nursing interventional program and alternative strategies for the health promotion lifestyle in college women.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.29 no.3B
• /
• pp.325-338
• /
• 2004

As the recent rapid development of internet technology and the wide spread of multimedia communication, massive increase of network traffic causes some problems such as the lack of network paths and the bad quality of service. To resolve these problems, this paper presents a traffic control agent that can perform the dynamic resource allocation by controlling traffic flows on a DiffServ network. In addition, this paper presents a router that can support DiffServ on Linux to support selective QoS in IP network environment. To implement a method for selective traffic transmission based on priority on a DiffServ router, this paper changes the queuing discipline in Linux, and presents the traffic control agent so that it can efficiently control routers, efficiently allocates network resources according to service requests, and relocate resources in response to state changes of the network. Particularly for the efficient processing of Assured Forwarding(AF) Per Hop Behavior(PHB), this paper proposes an ACWF$^2$Q$^{+}$ packet scheduler on a DiffServ router to enhance the throughput of packet transmission and the fairness of traffic services.s.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.14 no.3
• /
• pp.33-45
• /
• 1987

The Seonjeong royal tomb is one of many historic sites in and around Seoul city and its natural environment and landscape have born damaged seriously by heavy use. So conservation planning with an estimation of reasonable carrying capacity shall be required In aspect of not only historic site conservation, but also urban forest and nature park management. Eight sites were sampled with clumped sampling method during July of 1986 and five quadrats were examined in each site. Environmental factors, actual vegetation, and environmental impact grade were investigated in field and vegetational structure was analyzed by estimation of importance value, species diversity, similarity index, DBH class distribution, etc. The result of this study can be summarized as follows. 1. Damage on soil and vegetation of middle and lower layer increased according to amount of users'impact. 2. Semi - natural vegetation covered 63% of the total area(22.2 ha) and its major species were Pinus densiflora, Quercus aliena, Q mongolica, Sorbus alnifolia, etc. Pinus densiflora was a dominant species in heavy impact area. 3. Environmental impact grade 3, 4 and 5 area covered 51% of the seminatural vegetation, Especially, the area of impact grade 4 and 5 should be restored because self-refair seemed to be impossible. 4. The semi-natural vegetation was classified with four plant communities; two P.densiflora comm., Q. mongolica-P. densiflora comm. and Q. aliena comm. One of the P. densifolra comm. was destroyed seriously with no younger trees in middle and lower layer by overuse impact and would be bareland soon. But Q. aliena comm.in light impact area showed just completion of plant succession from P. densiflora comm.