• Journal of Communications and Networks
• /
• 제18권1호
• /
• pp.50-64
• /
• 2016

Nowadays, smart meter (SM) technology is widely effectively used. In addition, power allocation (PA) and channel selection (CS) are considered problems with many proposed approaches. In this paper, we will suggest a specific scenario for an SM configuration system and show how to solve the optimization problem for transmission between SMs and the data concentrator unit (DCU), the center that collects the data from several SMs, via simulation. An efficient CS with PA scheme is proposed in the TV white space system, which uses the TV band spectrum. On the basic of the optimal configuration requirements, SMs can have a transmission schedule and channel selection to obtain the optimal efficiency of using spectrum resources when transmitting data to the DCU. The optimal goals discussed in this paper are the maximum capacity or maximum channel efficiency and the maximum allowable power of the SMs used to satisfy the quality of service without harm to another wireless system. In addition, minimization of the interference to the digital television system and other SMs is also important and needs to be considered when the solving coexistence scenario. Further, we propose a process that performs an interference analysis scheme by using the spectrum engineering advanced Monte Carlo analysis tool (SEAMCAT), which is an integrated software tool based on a Monte-Carlo simulation method. Briefly, the process is as follows: The optimization process implemented by genetic evolution optimization engines, i.e., a genetic algorithm, will calculate the best configuration for the SM system on the basis of the interference limitation for each SM by SEAMCAT in a specific configuration, which reaches the solution with the best defined optimal goal satisfaction.

• 경영정보학연구
• /
• 제25권1호
• /
• pp.47-73
• /
• 2023

본 연구는 인공지능 기법 중 다중레이블 속성선택 방법을 적용하여 복잡한 경영환경에서 의사결정의 효과성을 증대시키는 방안을 설명한다. 인공지능 기반의 의사결정 시스템은 의사결정자의 선택과 판단을 돕거나, 대신하는 중요한 역할을 한다. 더욱이 최근 인공지능을 중심으로 한 비즈니스 의사결정은 기업의 성장 동력으로 평가받는데, 이를 위해서는 효과적인 의사결정 방법이 수반되어야 한다. 이에 본 연구는 의미 있는 속성값을 선별하는 CFS-BR(이진연관성 접근 기반의 상관관계 속성선택 모델)을 제안하여, 효과적인 의사결정을 지원하는 것을 돕는다. 예시데이터와 실증데이터의 분석 결과, CFS-BR은 유의미한 속성을 최상우선선별 알고리즘 기반으로 최상의 조합을 선별하므로 효율적 의사결정을 지원할 수 있고, 기존의 다중 레이블 속성선택 방법과 비교하였을 때 정확도가 높은 것으로 보아 효과적인 의사결정을 증대시키는 데 유용하다.

• Nuclear Engineering and Technology
• /
• 제54권4호
• /
• pp.1526-1533
• /
• 2022

Small modular reactors have garnered considerable attention in the recent years. Plate fuel elements exhibit a good application prospect in small modular pressurized water reactors for marine applications. Further, improved economic benefits can be achieved by extending the core lifetime of small modular reactors. However, it is necessary to realize a large initial residual reactivity for achieving a relatively long burnup depth finally. Thus, the selection of a suitable burnable poison (BP) is a crucial factor that should be considered in the design of small modular reactors. In this study, some candidate BPs are selected to realize the effective control of reactivity. The results show that ²³¹Pa₂O₃, ²⁴⁰Pu₂O₃, ¹⁶⁷Er₂O₃, PACS-J, and PACS-L are ideal candidates of BP, and since the characteristics of BP can increase the final burnup depth of assembly, the economic benefits are gained. Additionally, an optimal combination scheme of BPs is established. Specifically, it is proved that through a reasonable combination of BPs, a low reactivity fluctuation during the lifetime can be achieved, leading to a large final burnup depth.

• Human Ecology Research
• /
• 제60권4호
• /
• pp.565-576
• /
• 2022

The purpose of this study is to identify the effect of Home Economics Instruction applying Flipped and Problem-Based Learning (FPBL) on Korean middle-school students' metacognition skill. The study uses a pre-post design test of the same group. There were 151 participants (77 male and 74 female) who were middle-school students in the third grade. Two hours of classes on 'Food Selection and Storage' were given per week for three weeks - a total of six hours. Analysis using the t-test revealed a statistically significant difference between the pre-test and the post-test, supporting the conclusion that participating in the class improved the metacognition, food selection, and storage behavior scores of the middle-school students. All area scores and overall averages of metacognitive sub-elements such as planning, monitoring, regulation, and evaluation also improved after taking FPBL classes. From the results of this study, Home Economics Instruction applying FPBL is an effective teaching method for improving middle-school students' metacognition.

• 전자공학회논문지
• /
• 제50권8호
• /
• pp.39-44
• /
• 2013

LTE(Long Term Evolution)-Advanced에서는 저전력 피코셀(picocell)과 같은 소형셀을 중첩하여 배치해 시스템 성능을 향상시키기 위한 HetNet(Heterogeneous Network)에 대한 연구가 활발히 진행되고 있다. 또한 HetNet에서 데이터 오프로딩 효과를 증대시키기 위해 셀 영역 확장(CRE: Cell Range Expansion) 기술이 소개되었다. 본 논문에서는 최적의 오프로딩 효과를 위해 SINR(Signal to Interference plus Noise Ratio) 기반 셀 선택 기법을 제안한다. 셀 확장 영역에 존재하는 사용자의 간섭 관리를 위해 ABS를 사용하며, 스펙스럼 효율을 증가시키기 위하여 동적인 ABS 비율을 사용한다. 모의실험 결과, 제안한 기법에서 피코셀뿐만 아니라 매크로셀 사용자의 스펙트럼 효율이 향상되어 전체적인 사용자의 성능이 향상 된 것을 볼 수 있다.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제10권11호
• /
• pp.5381-5399
• /
• 2016

Currently, the quantize-and-forward (QF) scheme with high order modulation and quantization has rather high complexity and it is thus impractical, especially in multiple relay cooperative communications. To overcome these deficiencies, an improved low complex QF scheme is proposed by the combination of the low order binary phase shift keying (BPSK) modulation and the 1-bit and 2-bit quantization, respectively. In this scheme, the relay selection is optimized by the best relay position for best bit-error-rate (BER) performance, where the relays are located closely to the destination node. In addition, an optimal power allocation is also suggested on a total power constraint. Finally, the BER and the achievable rate of the low order 1-bit, 2-bit and 3-bit QF schemes are simulated and analyzed. Simulation results indicate that the 3-bit QF scheme has about 1.8~5 dB, 4.5~7.5 dB and 1~2.5 dB performance gains than those of the decode-and-forward (DF), the 1-bit and 2-bit QF schemes, at BER of $10^{-2}$, respectively. For the 2-bit QF, the scheme of the normalized Source-Relay (S-R) distance with 0.9 has about 5dB, 7.5dB, 9dB and 15dB gains than those of the distance with 0.7, 0.5, 0.3 and 0.1, respectively, at BER of $10^{-3}$. In addition, the proposed optimal power allocation saves about 2.5dB much more relay power on an average than that of the fixed power allocation. Therefore, the proposed QF scheme can obtain excellent features, such as good BER performance, low complexity and high power efficiency, which make it much pragmatic in the future cooperative communications.

• 대한영양사협회학술지
• /
• 제12권4호
• /
• pp.329-341
• /
• 2006

The purposes of the study were to examine food purchasing management practices and to assess dietitians' awareness on food quality standards, use of food purchasing guidelines(food quality guidelines, supplier selection criteria), and organizational collaboration related to purchasing at school food service. A total of 400 dietitians working at elementary schools in Kyunggi Province were surveyed and 247 responses were returned. Excluding responses with significant missing data, 240 responses(60%) were used for data analysis. Compared to the previous reports, competitive bidding and shorter contract periods were preferred for purchasing food supplies. A dietitian, school staff, and food service staff participated in receiving and inspection together at 58.4% of the schools. An average score of the dietitians' awareness on the food quality standards was 3.28 based on a 5-point scale(1:strongly disagree, 5:strongly agree). Their awareness scores for the quality standards related to the genetically modified organism foods, organic foods, and pesticide residues were the lowest. The awareness scores increased significantly with their age(p<.001). In general, the food purchasing guidelines were used well at the schools ; the usage levels of the food quality guidelines and supplier selection criteria were significantly different by length of operation(p<.05) and dietitians' age(p<.05), respectively. The dietitians' perception score of the organizational collaboration related to purchasing was rated 3.46 and differed significantly by dietitians' educational background(p<.05). For improving food procurement management, standardized food quality and purchasing criteria need to be developed. As the demands on high quality food supplies increase for school food service, the dietitians should improve their knowledges on the food quality standards and implement effective and creative purchasing methods.

• International Journal of Stem Cells
• /
• 제16권4호
• /
• pp.438-447
• /
• 2023

Recently, ex-vivo gene therapy has emerged as a promising approach to enhance the therapeutic potential of mesenchymal stem cells (MSCs) by introducing functional genes in vitro. Here, we explored the need of using selection markers to increase the gene delivery efficiency and evaluated the potential risks associated with their use in the manufacturing process. We used MSCs/CD that carry the cytosine deaminase gene (CD) as a therapeutic gene and a puromycin resistance gene (PuroR) as a selection marker. We evaluated the correlation between the therapeutic efficacy and the purity of therapeutic MSCs/CD by examining their anti-cancer effect on co-cultured U87/GFP cells. To simulate in vivo horizontal transfer of the PuroR gene in vivo, we generated a puromycin-resistant E. coli (E. coli/PuroR) by introducing the PuroR gene and assessed its responsiveness to various antibiotics. We found that the anti-cancer effect of MSCs/CD was directly proportional to their purity, suggesting the crucial role of the PuroR gene in eliminating impure unmodified MSCs and enhancing the purity of MSCs/CD during the manufacturing process. Additionally, we found that clinically available antibiotics were effective in inhibiting the growth of hypothetical microorganism, E. coli/PuroR. In summary, our study highlights the potential benefits of using the PuroR gene as a selection marker to enhance the purity and efficacy of therapeutic cells in MSC-based gene therapy. Furthermore, our study suggests that the potential risk of horizontal transfer of antibiotics resistance genes in vivo can be effectively managed by clinically available antibiotics.

• Genomics & Informatics
• /
• 제6권4호
• /
• pp.173-180
• /
• 2008

The human genome has evolved as a consequence of evolutionary forces, such as natural selection. In this study, we investigated natural selection on the human genes by comparing the numbers of nonsynonymous (NS) and synonymous (S) mutations in individual genes. We initially collected all coding SNP data of all human genes from the public dbSNP. Among the human genes, we selected 3 different selection groups of genes: positively selected genes (NS/S${\geq}$3), negatively selected genes (NS/S${\leq}$1/3) and neutral selection genes (0.9

• 대한원격탐사학회지
• /
• 제33권5_1호
• /
• pp.455-467
• /
• 2017

초분광 영상을 이용한 표적 탐지를 수행할 때에는 인접한 분광 밴드의 중복성의 문제 및 고차원 데이터로 인해 발생하는 방대한 계산량의 문제점을 해결하기 위한 특징 추출 과정이 필수적이다. 본 연구는 기계 학습 분야의 특징 선택 기법을 초분광 밴드 선택에 적용하기 위해 $L_{2,1}$-norm regression 모델을 이용한 새로운 밴드 선택 기법을 제안하였으며, 제안한 밴드 선택 기법의 성능 분석을 위해 표적이 존재하는 초분광영상을 직접 촬영하고 이를 바탕으로 표적 탐지를 수행한 결과를 분석하였다. 350 nm~2500 nm 파장 대역에서 밴드 수를 164개에서 약 30~40개로 감소시켰을 때 Adaptive Cosine Estimator(ACE) 탐지 성능이 유지되거나 향상되는 결과를 보였다. 실험 결과를 통해 제안한 밴드 선택 기법이 초분광 영상에서 탐지에 효율적인 밴드를 추출해 내며, 이를 통해 성능의 감소 없이 데이터의 차원 감소를 수행할 수 있어 향후 실시간 표적 탐지 시스템의 처리 속도 향상에 도움을 줄 수 있을 것으로 보인다.