• Title/Summary/Keyword: Choi criteria

Search Result 2,154, Processing Time 0.029 seconds

A Constructive Algorithm of Fuzzy Model for Nonlinear System Modeling (비선형 시스템 모델링을 위한 퍼지 모델 구성 알고리즘)

  • Choi, Jong-Soo
    • Proceedings of the KIEE Conference
    • /
    • 1998.11b
    • /
    • pp.648-650
    • /
    • 1998
  • This paper proposes a constructive algorithm for generating the Takagi-Sugeno type fuzzy model through the sequential learning from training data set. The proposed algorithm has a two-stage learning scheme that performs both structure and parameter learning simultaneously. The structure learning constructs fuzzy model using two growth criteria to assign new fuzzy rules for given observation data. The parameter learning adjusts the parameters of existing fuzzy rules using the LMS rule. To evaluate the performance of the proposed fuzzy modeling approach, well-known benchmark is used in simulation and compares it with other modeling approaches.

  • PDF

IRREDUCIBLE POLYNOMIALS WITH REDUCIBLE COMPOSITIONS

  • Choi, Eun-Mi
    • Honam Mathematical Journal
    • /
    • v.33 no.3
    • /
    • pp.355-366
    • /
    • 2011
  • In this paper we investigate criteria that for an irreducible monic quadratic polynomial f(x) ${\in}$ $\mathbb{Q}$[x], $f{\circ}g$ is reducible over $\mathbb{Q}$ for an irreducible polynomial g(x) ${\in}$ $\mathbb{Q}$[x]. Odoni intrigued the discussion about an explicit form of irreducible polynomials f(x) such that $f{\cric}f$ is reducible. We construct a system of infitely many such polynomials.

A Study on PWM Buck-Boost AC-AC Converter for Improvement of Power Quality of Custom Power (Custom Power의 전력품질 향상을 위한 PWM Buck-Boost AC-AC 컨버터에 대한 연구)

  • Choi Nam-Sup
    • Proceedings of the KIPE Conference
    • /
    • 2002.11a
    • /
    • pp.129-132
    • /
    • 2002
  • In this paper, a PWM Buck-Boost AC-AC converter for improvement of power quality of custom power is presented. The PWM Buck-Boost AC-AC converter is modelled by using circuit DQ transformation whereby the both static and dynamic characteristics are analyzed completely. Finally, the converter system is implemented with the design criteria and the experimental results show the validity of modelling and analysis.

  • PDF

Development of evaluation criteria for selection of source code security vulnerability verification rules for industrial control systems (산업제어시스템의 소스코드 보안 취약점 검증 룰 선정을 위한 평가 기준 개발)

  • Kim, Eunbi;Choi, Yisoo;Han, Dongjoon
    • Proceedings of the Korea Information Processing Society Conference
    • /
    • 2021.11a
    • /
    • pp.449-452
    • /
    • 2021
  • 산업제어시스템은 IT 기술의 발전에 따라 다양한 기기 환경과 네트워크를 적용해 진화하고 있다. 이러한 상황에서 사이버 보안의 위협은 가중되고 있으며, 이를 예방하는 방법의 하나로 산업제어시스템에 탑재되는 소프트웨어의 소스코드 개발 과정에서 보안 취약점을 예방하기 위해 소스코드 보안 룰을 적용하여 위반사항을 제거한다. 본 연구에서는 소스코드 보안 룰에서 적용 우선순위를 선정하기 위한 가이드를 개발한다.

Compensation Criteria for Investigation Services and Strengthening Normative Force Plans for Detailed Qualification Criteria for Examination of Archaeological Heritage (매장문화재 조사용역 대가기준과 적격심사 세부기준 제도의 규범력 강화 방안)

  • Choi, Min-jeong
    • Korean Journal of Heritage: History & Science
    • /
    • v.52 no.2
    • /
    • pp.240-253
    • /
    • 2019
  • Archaeological heritages are precious cultural relics and public assets that must be preserved, conserved, and shared with people all over the world. Investigating archaeological heritage is valuable and plays an important role for the public good; our ancestors' cultures can be restored, and it helps with developing a clear understanding of the cultural and social aspects of a historical period as well as teaches about historical factors unreported in the literature. One of the most basic and important conditions necessary for recognizing the value and importance of archaeological heritage investigation, expertise, and quality improvement is to establish detailed criteria for investigation services and the qualification examination of archaeological heritage. Observation of detailed criteria and the qualification examination of archaeological heritage can partially demonstrate society's recognition of strengthening transparency, public property, and the objectivity of the investigation of archaeological heritage. However, the detailed criteria for investigation services and the qualification examination of archaeological heritage currently implemented as administrative rules are neither followed by all institutes in the public and private sectors nor the government. Thus, there are serious problems in terms of the effectiveness and stability of institutions. The detailed criteria for the qualification examination breach the principle of statutory reservation, the principle of statutory regulation, and regulations on the announcement and management of orders and rules. Non-compliance with compensation criteria for investigation services or with detailed criteria for the qualification examination of archaeological heritage will be one of the reasons for the failure of the investigation foundation for archaeological heritage in the future. That is, it will result in the expansion, reproduction, and repetition of a vicious cycle of conflict between developers, who are the decision-makers responsible for selecting an investigating organization for archaeological heritage and determining the cost, and investigating organizations. This includes the impractical shortening of investigation periods and reducing costs by developers, distrust of the values and the importance of investigations of archaeological heritage, a decrease in quality, accidents caused by a lack of safety, a lack of occupational ethics, and non-recruitment of new experts, etc. Therefore, it is necessary to change the structure from a vicious cycle to a virtuous cycle, and promote the enactment of regulations that will ensure effectiveness and stability in the process of attaining the goals of the institution and application of the institution, as well as the continuous advancement of work to fill the gaps with reality.

A Suggestion of Mix, Construction Method and Quality Control Criteria of Fine-size Exposed Aggregate PCC Pavement by Experimental Construction (시험시공을 통한 소입경 골재노출 콘크리트 포장의 배합, 시공 및 품질관리 기준 제안)

  • Lee, Seung-Woo;Kim, Young-Kyu;Choi, Don-Hwa;Shim, Jae-Won;Yoo, Tae-Seok
    • International Journal of Highway Engineering
    • /
    • v.13 no.3
    • /
    • pp.51-63
    • /
    • 2011
  • Surface of fine-size exposed aggregate portland cement concrete pavements(FS-EAPCC) is consist by exposed coarse aggregate to remove upper 2~3mm mortar of concrete slabs. Advantages of FS-EAPCC are maintaining low-noise and adequate skid-resistance level during the performance period. However, FS-EAPCC is required rational management criteria for field application, since it is early stage for application. Design construction and quality control criteria of FS-EAPCC was temporary laboratory tests which including optimum mix and exposing method, selection of adequate aggregate, resistance against, environmental loading and etc. However, these criteria need to be validated base on field application. In this study, experimental constructions were performed and construction procedure and quality control criteria were suggested based on the performance of the FS-EAPCC.

Systemic review: Herbal Medicines in the Treatment of Osteoarthritis in Pubmed and Chinese Medical Journals (퇴행성관절염(退行性關節炎) 한방치료(韓方治療)에 대(對)한 최근(最新) 연구(硏究) 동향(動向) - 임상연구(臨床硏究) 방법론(方法論)을 중심(中心)으로 -)

  • Seo, Byung-kwan;Ryu, Seong-ryong;Lee, Song-shil;Huh, Jeong-eun;Baek, Yong-hyeon;Lee, Jae-dong;Choi, Do-young;Cho, Yoon-je;Kim, Nam-jae;Park, Dong-suk
    • Journal of Acupuncture Research
    • /
    • v.21 no.3
    • /
    • pp.265-282
    • /
    • 2004
  • Objective : The aim of this study was to review systemically clinical trials on the effectiveness and safety of herbal medicines in the treatment of osteoarthritis. Methods : Computerized literature searches were carried out on seven electronic databases, and hand-searching on some chinese medical journals in library of Kyung Hee Medical Center. Trial data were extracted in a standardized, predefined manner and assessed independently. Results : 1. Thirty reports of clinical trials and two reports of meta-analyses concerning herbal medicine were collected and reviewed. Among these reports three medical herbs were applied as topical medicine and others as internal medicine. 2. The western studies established NSAIDs or placebo as their control group. Five chinese reports established formulated herb pill(Ruanshnagshenjin pill) as their control group and Six did not establish a control group at all. 3. ACR was the most highly used diagnostic criteria in the western studies while the Chinese used their official criteria established by their government or the criteria of their text books. 4. 20 reports chose the Lequesne functional index, SHAQ, WOMAC OA index, AIMS, and their own unique scoring system as the criteria of analysing the effect. Others chose clinical symptoms, articular functions, and lab finding as their criteria. 5. 7 single herbs and 19 formulated herbs were studied. Among the formulated herbs, Achyranthes japonica was studied in 10 of the studies and Angelica gigantis Radix in 8, making them the most often studied herbs among the studies.

  • PDF

Consideration on Rating Method for Heavy Impact Sound Taking Account of the Characteristics of Floor Vibration and Impact Sources (바닥 진동 거동 및 충격원 특성을 고려한 바닥 중량 충격음 평가방법 고찰)

  • Lee, Min-Jung;Choi, Hyun-Ki
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.21 no.4
    • /
    • pp.69-79
    • /
    • 2017
  • The purpose of this study is to reconsider the rating method for the floor impact sound insulation performance in current criterion. Although there are some arguments about proper standard heavy impact source with reproducibility of actual impact source in residence building, bang machine is adopted as the only standard heavy impact source in domestic criterion. To inspect the rating methods of evaluation criteria, this study conducted vibration test for both of standard heavy impact sources and actual impact sources. Using the test results, the floor impact sound insulation performance levels were assessed by each of several criteria. In addition, low frequency noise beyond current criteria was evaluated. Consequently, the floor impact sound levels have different performance levels according to adopted criteria, and measured floor impact sounds are bound to annoy the neighbors in the low frequency range. Current criteria does not consider the spectrum characteristics of floor impact sound according to impact sources and low frequency noise. This may cause the difference between the floor impact sound insulation performance level and human perception. Thus current criterion needs to be complemented to reflect the spectrum characteristics of floor impact sound levels according to impact sources and sound pressure levels in low frequency range.

Establishing the Concept of Buffer for a High-level Radioactive Waste Repository: An Approach (고준위폐기물처분장의 완충재 개념 도출: 접근방안)

  • Lee, Jae Owan;Lee, Minsoo;Choi, Heuijoo
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
    • /
    • v.13 no.4
    • /
    • pp.283-293
    • /
    • 2015
  • The buffer is a key component of the engineered barrier system in a high-level radioactive waste (HLW) repository. The present study reviewed the requirements and functional criteria of the buffer reported in literature, and also based on the results, proposed an approach to establish a buffer concept which is applicable to an HLW repository in Korea. The hydraulic conductivity, radionuclide-retarding capacity (equilibrium distribution coefficient and diffusion coefficient), swelling pressure, thermal conductivity, mechanical properties, organic carbon content, and illitization rate were considered as major technical parameters for the functional criteria of the buffer. Domestic bentonite (Ca-bentonite) and, as an alternative, MX-80 (Na-bentonite) were proposed for the buffer of an HLW repository in Korea. The technical specifications for those proposed bentonites were set to parameter values that conservatively satisfy Korea's functional criteria for the Ca-bentonite and Swedish criteria for the Na-bentonite. The thickness of the buffer was determined by evaluating the means of shear behavior, radionuclide release, and heat conduction, which resulted in the proper buffer thickness of 0.25 to 0.5 m. However, the final thickness of the buffer should be determined by considering coupled thermal-hydraulic-mechanical evaluation and economics and engineering aspects as well.