• Title/Summary/Keyword: GREEDY

Search Result 428, Processing Time 0.025 seconds

A Effective Ant Colony Algorithm applied to the Graph Coloring Problem (그래프 착색 문제에 적용된 효과적인 Ant Colony Algorithm에 관한 연구)

  • Ahn, Sang-Huck;Lee, Seung-Gwan;Chung, Tae-Choong
    • The KIPS Transactions:PartB
    • /
    • v.11B no.2
    • /
    • pp.221-226
    • /
    • 2004
  • Ant Colony System(ACS) Algorithm is new meta-heuristic for hard combinational optimization problem. It is a population-based approach that uses exploitation of positive feedback as well as greedy search. Recently, various methods and solutions are proposed to solve optimal solution of graph coloring problem that assign to color for adjacency node($v_i, v_j$) that they has not same color. In this paper introducing ANTCOL Algorithm that is method to solve solution by Ant Colony System algorithm that is not method that it is known well as solution of existent graph coloring problem. After introducing ACS algorithm and Assignment Type Problem, show the wav how to apply ACS to solve ATP And compare graph coloring result and execution time when use existent generating functions(ANT_Random, ANT_LF, ANT_SL, ANT_DSATUR, ANT_RLF method) with ANT_XRLF method that use XRLF that apply Randomize to RLF to solve ANTCOL. Also compare graph coloring result and execution time when use method to add re-search to ANT_XRLF(ANT_XRLF_R) with existent generating functions.

Analysis of Geographic Network Structure by Business Relationship between Companies of the Korean Automobile Industry (한국 자동차산업의 기업간 거래관계에 의한 지리적 네트워크 구조 분석)

  • KIM, Hye-Lim;MOON, Tae-Heon
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.24 no.3
    • /
    • pp.58-72
    • /
    • 2021
  • In July 2021, UNCTAD classified Korea as a developed country. After the Korean War in the 1950s, economic development was promoted despite difficult conditions, resulting in epoch-making national growth. However, in order to respond to the rapidly changing global economy, it is necessary to continuously study the domestic industrial ecosystem and prepare strategies for continuous change and growth. This study analyzed the industrial ecosystem of the automobile industry where it is possible to obtain transaction data between companies by applying complexity spatial network analysis. For data, 295 corporate data(node data) and 607 transaction data (link data) were used. As a result of checking the spatial distribution by geocoding the address of the company, the automobile industry-related companies were concentrated in the Seoul metropolitan area and the Southeastern(Dongnam) region. The node importance was measured through degree centrality, betweenness centrality, closeness centrality, and eigenvector centrality, and the network structure was confirmed by identifying density, distance, community detection, and assortativity and disassortivity. As a result, among the automakers, Hyundai Motor, Kia Motors, and GM Korea were included in the top 15 in 4 indicators of node centrality. In terms of company location, companies located in the Seoul metropolitan area were included in the top 15. In terms of company size, most of the large companies with more than 1,000 employees were included in the top 15 for degree centrality and betweenness centrality. Regarding closeness centrality and eigenvector centrality, most of the companies with 500 or less employees were included in the top 15, except for automakers. In the structure of the network, the density was 0.01390522 and the average distance was 3.422481. As a result of community detection using the fast greedy algorithm, 11 communities were finally derived.

Conformer with lexicon transducer for Korean end-to-end speech recognition (Lexicon transducer를 적용한 conformer 기반 한국어 end-to-end 음성인식)

  • Son, Hyunsoo;Park, Hosung;Kim, Gyujin;Cho, Eunsoo;Kim, Ji-Hwan
    • The Journal of the Acoustical Society of Korea
    • /
    • v.40 no.5
    • /
    • pp.530-536
    • /
    • 2021
  • Recently, due to the development of deep learning, end-to-end speech recognition, which directly maps graphemes to speech signals, shows good performance. Especially, among the end-to-end models, conformer shows the best performance. However end-to-end models only focuses on the probability of which grapheme will appear at the time. The decoding process uses a greedy search or beam search. This decoding method is easily affected by the final probability output by the model. In addition, the end-to-end models cannot use external pronunciation and language information due to structual problem. Therefore, in this paper conformer with lexicon transducer is proposed. We compare phoneme-based model with lexicon transducer and grapheme-based model with beam search. Test set is consist of words that do not appear in training data. The grapheme-based conformer with beam search shows 3.8 % of CER. The phoneme-based conformer with lexicon transducer shows 3.4 % of CER.

An Exact Division Algorithm for Change-Making Problem (거스름돈 만들기 문제의 정확한 나눗셈 알고리즘)

  • Lee, Sang-Un
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.22 no.3
    • /
    • pp.185-191
    • /
    • 2022
  • This paper proposed a division algorithm of performance complexity $O{\frac{n(n+1)}{2}}$ for a change-making problem(CMP) in which polynomial time algorithms are not known as NP-hard problem. CMP seeks to minimize the sum of the xj number of coins exchanged when a given amount of money C is exchanged for cj,j=1,2,⋯,n coins. Known polynomial algorithms for CMPs are greedy algorithms(GA), divide-and-conquer (DC), and dynamic programming(DP). The optimal solution can be obtained by DP of O(nC), and in general, when given C>2n, the performance complexity tends to increase exponentially, so it cannot be called a polynomial algorithm. This paper proposes a simple algorithm that calculates quotient by dividing upper triangular matrices and main diagonal for k×n matrices in which only j columns are placed in descending order of cj of n for cj ≤ C and i rows are placed k excluding all the dividers in cj. The application of the proposed algorithm to 39 benchmarking experimental data of various types showed that the optimal solution could be obtained quickly and accurately with only a calculator.

Feminizing of Real Estate Speculation -A Study on the Bokbuin in the Korean Narratives in 1970s~1980s (주거의 투기화, 투기의 여성화 -1970~1980년대 한국 서사에 나타난 복부인의 형상화 양상 연구)

  • Jun, Bong-Gwan
    • Journal of Popular Narrative
    • /
    • v.25 no.4
    • /
    • pp.321-359
    • /
    • 2019
  • In the 1970s, the full-scale development of the area now known as Gangnam began, ushering in the era of real estate investment on apartments which transformed housing styles in Korea. Apartments were pitched as the most ideal type of housing, creating a competitive market of high demand and skyrocketing prices. The apartments were also viewed as a means of quick asset investment among middle-class Koreans. Within this apartment frenzy stood the female real estate speculator, the bokbuin. This study seeks to locate the bokbuin in the real estate development market after the late 1970s. The apartment speculation boom cannot be attributed to the bokbuin alone, yet she became the target of public anger and criticism, singled-out as being responsible for fueling illegal and unethical investments. The apartment boom of the 1970s was in fact generated in large part by the government, developers, construction companies and realtors. While their pursuit of profit was deemed as legitimate, the bokbuin's conduct was mostly tainted by presumed illegitimate and greedy motivations. This study problematizes this gendering of real estate investment and treat the bokbuin as a byproduct of the family-centered culture in East Asia. Analyzing Im Kwon Taek's film "Mrs. Speculator", Park Ki Won's conte, "Bokbuin", Park Wan Seo's short story, "Children of Paradise", "The People of Seoul", this study shows that bokbuin's pursuit was not hers alone; it was the collective pursuit with her husband for the enhancement of family finances. This stud y argue that the bokbuin embodied the thickly misogynistic climate of the 1970s that projected the chaotic rise of greed onto the woman.

Optimization Algorithm for k-opt Swap of Generalized Assignment Problem (일반화된 배정 문제의 k-opt 교환 최적화 알고리즘)

  • Sang-Un Lee
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.23 no.5
    • /
    • pp.151-158
    • /
    • 2023
  • The researchers entirely focused on meta-heuristic method for generalized assignment problem(GAP) that is known as NP-hard problem because of the optimal solution within polynomial time algorithm is unknown yet. On the other hand, this paper proposes a heuristic greedy algorithm with rules for finding solutions. Firstly, this paper reduces the weight matrix of original data to wij ≤ bi/l in order to n jobs(items) pack m machines(bins) with l = n/m. The maximum profit of each job was assigned to the machine for the reduced data. Secondly, the allocation was adjusted so that the sum of the weights assigned to each machine did not exceed the machine capacity. Finally, the k-opt swap optimization was performed to maximize the profit. The proposed algorithm is applied to 50 benchmarking data, and the best known solution for about 1/3 data is to solve the problem. The remaining 2/3 data showed comparable results to metaheuristic techniques. Therefore, the proposed algorithm shows the possibility that rules for finding solutions in polynomial time exist for GAP. Experiments demonstrate that it can be a P-problem from an NP-hard.

Performance Evaluation of a Dynamic Bandwidth Allocation Algorithm with providing the Fairness among Terminals for Ethernet PON Systems (단말에 대한 공정성을 고려한 이더넷 PON 시스템의 동적대역할당방법의 성능분석)

  • Park Ji-won;Yoon Chong-ho;Song Jae-yeon;Lim Se-youn;Kim Jin-hee
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.29 no.11B
    • /
    • pp.980-990
    • /
    • 2004
  • In this paper, we propose the dynamic bandwidth allocation algorithm for the IEEE802.3ah Ethernet Passive Optical Network(EPON) system to provide the fairness among terminals, and evaluate the delay-throughput performance by simulation. For the conventional EPON systems, an Optical Line Termination (OLT) schedules the upstream bandwidth for each Optical Network Unit (ONU), based on its buffer state. This scheme can provide a fair bandwidth allocation for each ONU. However, it has a critical problem that it does not guarantee the fair bandwidth among terminals which are connected to ONUs. For an example, we assume that the traffic from a greedy terminal increases at a time. Then, the buffer state of its ONU is instantly reported to the OLT, and finally the OW can get more bandwidth. As a result, the less bandwidth is allocated to the other ONUs, and thus the transfer delay of terminals connected to the ONUs gets inevitably increased. Noting that this unfairness problem exists in the conventional EPON systems, we propose a fair bandwidth allocation scheme by OLT with considering the buffer state of ONU as welt as the number of terminals connected it. For the performance evaluation, we develop the EPON simulation model with SIMULA simulation language. From the result of the throughput-delay performance and the dynamics of buffer state along time for each terminal and ONU, respectively, one can see that the proposed scheme can provide the fairness among not ONUs but terminals. Finally, it is worthwhile to note that the proposed scheme for the public EPON systems might be an attractive solution for providing the fairness among subscriber terminals.

A Study on the aesthetic of Calligraphy on Changam, Lee Samman (창암(蒼巖) 이삼만(李三晩)의 서예미학(書藝美學) 고찰)

  • Kim, Doyoung
    • The Journal of the Convergence on Culture Technology
    • /
    • v.6 no.2
    • /
    • pp.99-106
    • /
    • 2020
  • Changam, Lee Samman(1770~1845), who created his own handwriiting to be referred to as the three great writers of the late Joseon Dynasty, invented as the original 'Haengunyusu Typeface' and developed Calligraphy spirit of DonggugJinche in Honam province. He ultimately pursued the state of tonglyeong by raising the personality of 'writing is the person's personality' and the attitude of learning the old. Through the book chang-amseogyeol, he basically polished Haeseo of Han Dynasty and Wi Dynasty and emphasized that Haengseo and Choseo are done automatically when muscle strength and bone strength are established. And since calligraphy originated from 'nature', it goes through the 'Beobcheongwijin' spirit. After doing so, expressed the state of tonglyeong of " mubeob-ibeob ", the stage of reaching. In addition, Changam showed the aesthetic that you can get the novelty by pursuing the philosophy of 'Wu' and the 'beauty of Stupid and Lacking' based on LaoTzu and ChuangTzu. This is a philosophy that follows nature's logic to reveal nature's nature. And it is an aesthetic that protects his 'True Wu' without knowing and greedy. On the other hand, Changam promoted natural and vital beauty through force in the method of using the brush. He suggested the 'Push and Hard' of the Han dynasty, pushing it with force using this power properly. In particular, the feeling of an IlunMujeog brush in 『Changam Calligraphy-The cloud stays Poem』 overflows with the vitality and bizarre and strange dynamism of the spirit and typeface as eum-yang harmonizes with each other. In addition, the beauty of Push and Hard containing polyeoghamse is misaligned, but it has achieved a natural aesthetic without invading. This work demonstrates the real look of Changam choseo. In addition, the beauty of Push and Hard containing polyeoghamse is misaligned, but it has achieved a natural aesthetic without invading. Changam proves the real look of "Haedong's best Chose Maestro".