• Title/Summary/Keyword: Tool Selection

Search Result 830, Processing Time 0.023 seconds

A two-stage damage detection approach based on subset selection and genetic algorithms

  • Yun, Gun Jin;Ogorzalek, Kenneth A.;Dyke, Shirley J.;Song, Wei
    • Smart Structures and Systems
    • /
    • v.5 no.1
    • /
    • pp.1-21
    • /
    • 2009
  • A two-stage damage detection method is proposed and demonstrated for structural health monitoring. In the first stage, the subset selection method is applied for the identification of the multiple damage locations. In the second stage, the damage severities of the identified damaged elements are determined applying SSGA to solve the optimization problem. In this method, the sensitivities of residual force vectors with respect to damage parameters are employed for the subset selection process. This approach is particularly efficient in detecting multiple damage locations. The SEREP is applied as needed to expand the identified mode shapes while using a limited number of sensors. Uncertainties in the stiffness of the elements are also considered as a source of modeling errors to investigate their effects on the performance of the proposed method in detecting damage in real-life structures. Through a series of illustrative examples, the proposed two-stage damage detection method is demonstrated to be a reliable tool for identifying and quantifying multiple damage locations within diverse structural systems.

Estimating the Effects of Multipath Selection on Concurrent Multipath Transfer

  • Wang, Jingyu;Liao, Jianxin;Wang, Jing;Li, Tonghong;Qi, Qi
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.8 no.4
    • /
    • pp.1406-1423
    • /
    • 2014
  • Multi-mode device which combines multiple access technologies into a device will offer more cost-effective solution than a sole access implementation. Its concurrent multipath transfer (CMT) technology can transmit media flows over multiple end-to-end paths simultaneously, which is essential to select at least two paths from all available paths. At real networks, different paths are likely to overlap each other and even share bottleneck, which can weaken the path diversity gained through CMT. Spurred by this observation, it is necessary to select multiple independent paths as much as possible to avoid underlying shared bottleneck between topologically joint paths. Recent research in this context has shown that different paths with shared bottleneck can weaken the path diversity gained through CMT. In our earlier work, a grouping-based multipath selection (GMS) mechanism is introduced and developed. However, how to estimating the selection is still to be resolved. In this paper, we firstly introduce a Selection Correctness Index (SCI) to evaluate the correctness of selection results in actual CMT experiment. Therefore, this metric is helpful to discuss and validate the accuracy of the output paths. From extensive experiments with a realized prototype, the proposed scheme provides better evaluation tool and criterion in various network conditions.

Proposing a Preferred Parts List and Developing a Search System for Common Parts (우선부품목록 선정방안 제시 및 공용화 검색 시스템 구축)

  • Yoon, Jaebok;Kim, Siok;Moon, Jinkyu;Hong, Sungmin;Lim, Hojung;Kim, Sanghan
    • Journal of Korean Society for Quality Management
    • /
    • v.48 no.4
    • /
    • pp.567-580
    • /
    • 2020
  • Purpose: The purpose of this study is to present a preferred parts list, establish a search tool for common parts, and propose a development plan for parts management. Methods: When selecting the preferred parts list, the weight of the selection of the military parts and the online site of the civilian parts were taken into account. By establishing a database of selected preferred parts list, we have established a system for searching common parts. Results: The results of this study are as follows; In order to establish parts management work in Korea's defense, it is necessary to improve the Defense Acquisition Program Act, Enforcement Decree (Rules), and the Regulations for Defense Acquisition Program Administration. Development of performance indicators for parts management is required, and establishment of procedures and standards for selection of preferred parts lists is required. Considerations for the selection of preferred parts list include whether they are used a lot in civilian products, whether they are used a lot, whether they are certified suppliers, whether they are national and industrial standard products, whether they perform well considering reliability, durability, and quality, and whether they can be supplied continuously. Conclusion: It is necessary to establish policies and systems related to parts management and to establish criteria for selecting preferred parts list for the development of domestic parts management tasks.

The Selection and Abrasion Assessment of Cutter on Shield Tunnelling in Weathered Soil - Seoul Subway Line 7 Extension, Construction Lot 703 (풍화암 지반에서의 쉴드 TBM 커터도구 선정 및 마모량 평가 - 서울지하철 7호선연장 703공구 중심으로)

  • Kim, Yong-Il;Lee, Sang-Han;Jeong, Du-Seok;Im, Jong-Yun;Park, Gwang-Jun;Park, Jun-Su
    • Proceedings of the Korean Society for Rock Mechanics Conference
    • /
    • 2006.09a
    • /
    • pp.59-79
    • /
    • 2006
  • The successful execution of shield tunnelling depends on the cutting ability of cutter. So the selection of shape, size and material of cutter according to geology condition is important work. Since shield tunnelling method was first invented in 1881, the cutting tool for rock has been developed owing to various experiments and researches, the study for soil, however, is insufficient. This paper introduces the shield tunnelling that will be carried out on weathered rock section (920m) of Seoul Subway Line 7 Extension C703. The shape and the material of cutter are discussed required for execution without replacement of cutter tool as well as for advance of excavation efficiency. In addition the estimation method of cutter abrasion in case of excavation on weathered soil is proposed and verified. Specially, the coefficient of abrasion for different soil and cutter is proposed by means of investigation into construction example of foreign country.

  • PDF

Development of Grouping Tool for Effective Collaborative Learning (효과적인 협동학습을 위한 모둠 구성 도구 개발)

  • Lee, KyungHee;Ko, Juhyung;Jwa, Chanik;Cho, Jungwon
    • Journal of Digital Convergence
    • /
    • v.16 no.7
    • /
    • pp.243-248
    • /
    • 2018
  • The most important factor for collaborative learning to be effective is the selection of tools that constitute groups. Grouping is to facilitate collaborative learning, learners form groups based on various characteristics. If a group of students fails to form properly due to the selection of the wrong tools, problems can arise where complaints from students can lead to lectures and the effects of learning. In this paper, we have implemented a group of configuration tools that considered improving learning effects and diagnosing bulling tendency. We have proposed a group composition tool that can take into consideration the learning effect and also diagnose the tendency of the bullring by constructing the group according to the teacher's preference by inputting the class preference and the student's grade through the sociometry survey. We expect that the teacher will be able to grasp the students' friendship in advance and cope with the bulling that can happen in the class, as well as the cooperative learning that can lead the class to improve the learning effect.

A Study on the Choosing Behavioral Factor of Restaurant Menus in Hotels (호텔레스토랑 이용객의 메뉴선택행동요인에 관한 연구 -서울 시내 특 1등급 관광호텔 양식당 중심으로-)

  • 김기영;김신정
    • Culinary science and hospitality research
    • /
    • v.6 no.3
    • /
    • pp.25-55
    • /
    • 2000
  • AS the number of tourist has been increased. hotel industry will be able to not be existed and developed if not adapted to the need of customer's which is changed according to the change of Hotel's function. Traditionally. F&B department is enlarged compared to the past. But. it cause negative result in terms of clear profit. A menu is a marketing tool which delivers restaurant's image aid message to customers and communicate need and wants to restaurant. So far, studies on menu have been done in an analytical way from a management's viewpoint and inadequate to reflect customer's need and wants. A research on customer's menu selection procedure is critical to satisfying their needs and wants yield profit. This study examined the theories on menu-design and customer behavior through literature review and verified hypotheses through an empirical analysis. A questionnaire-survey had been used in luxury hotel's main grills and all most restaurants in Seoul. Collected data were analyzed. using SPSS/PC+ package. The important findings are as follows. In this study is to examine the factors that have an influence on customer's menu selection. The factors affected the customers' menu selection of hotel restaurant in the four factors. Four factors are hotel's restaurant of environmental factor. menu-choice factor. value of menu items, information. Correction between the evaluation criteria and selection of menu was examined. All four evaluation criteria, menu-choice factor was found to be most strongly collected with selection of menu. In conclusion, As a study on the Customer' menu Selection Behavior factor of Restaurant Menus in Hotels, It raises to exert us in the menu management of hotel restaurant.

  • PDF

Single-Base Genome Editing in Corynebacterium glutamicum with the Help of Negative Selection by Target-Mismatched CRISPR/Cpf1

  • Kim, Hyun Ju;Oh, Se Young;Lee, Sang Jun
    • Journal of Microbiology and Biotechnology
    • /
    • v.30 no.10
    • /
    • pp.1583-1591
    • /
    • 2020
  • CRISPR/Cpf1 has emerged as a new CRISPR-based genome editing tool because, in comparison with CRIPSR/Cas9, it has a different T-rich PAM sequence to expand the target DNA sequence. Single-base editing in the microbial genome can be facilitated by oligonucleotide-directed mutagenesis (ODM) followed by negative selection with the CRISPR/Cpf1 system. However, single point mutations aided by Cpf1 negative selection have been rarely reported in Corynebacterium glutamicum. This study aimed to introduce an amber stop codon in crtEb encoding lycopene hydratase, through ODM and Cpf1-mediated negative selection; deficiency of this enzyme causes pink coloration due to lycopene accumulation in C. glutamicum. Consequently, on using double-, triple-, and quadruple-base-mutagenic oligonucleotides, 91.5-95.3% pink cells were obtained among the total live C. glutamicum cells. However, among the negatively selected live cells, 0.6% pink cells were obtained using single-base-mutagenic oligonucleotides, indicating that very few single-base mutations were introduced, possibly owing to mismatch tolerance. This led to the consideration of various target-mismatched crRNAs to prevent the death of single-base-edited cells. Consequently, we obtained 99.7% pink colonies after CRISPR/Cpf1-mediated negative selection using an appropriate single-mismatched crRNA. Furthermore, Sanger sequencing revealed that single-base mutations were successfully edited in the 99.7% of pink cells, while only two of nine among 0.6% of pink cells were correctly edited. The results indicate that the target-mismatched Cpf1 negative selection can assist in efficient and accurate single-base genome editing methods in C. glutamicum.

Genetic Parameters for Linear Type Traits and Milk, Fat, and Protein Production in Holstein Cows in Brazil

  • Campos, Rafael Viegas;Cobuci, Jaime Araujo;Kern, Elisandra Lurdes;Costa, Claudio Napolis;McManus, Concepta Margaret
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.28 no.4
    • /
    • pp.476-484
    • /
    • 2015
  • The objective of this study was to estimate genetic and phenotypic parameters for linear type traits, as well as milk yield (MY), fat yield (FY) and protein yield (PY) in 18,831 Holstein cows reared in 495 herds in Brazil. Restricted maximum likelihood with a bivariate model was used for estimation genetic parameters, including fixed effects of herd-year of classification, period of classification, classifier and stage of lactation for linear type traits and herd-year of calving, season of calving and lactation order effects for production traits. The age of cow at calving was fitted as a covariate (with linear and quadratic terms), common to both models. Heritability estimates varied from 0.09 to 0.38 for linear type traits and from 0.17 to 0.24 for production traits, indicating sufficient genetic variability to achieve genetic gain through selection. In general, estimates of genetic correlations between type and production traits were low, except for udder texture and angularity that showed positive genetic correlations (>0.29) with MY, FY, and PY. Udder depth had the highest negative genetic correlation (-0.30) with production traits. Selection for final score, commonly used by farmers as a practical selection tool to improve type traits, does not lead to significant improvements in production traits, thus the use of selection indices that consider both sets of traits (production and type) seems to be the most adequate to carry out genetic selection of animals in the Brazilian herd.

A Multi-Phase Decision Making Model for Supplier Selection Under Supply Risks (공급 리스크를 고려한 공급자 선정의 다단계 의사결정 모형)

  • Yoo, Jun-Su;Park, Yang-Byung
    • Journal of Korean Society of Industrial and Systems Engineering
    • /
    • v.40 no.4
    • /
    • pp.112-119
    • /
    • 2017
  • Selecting suppliers in the global supply chain is the very difficult and complicated decision making problem particularly due to the various types of supply risk in addition to the uncertain performance of the potential suppliers. This paper proposes a multi-phase decision making model for supplier selection under supply risks in global supply chains. In the first phase, the model suggests supplier selection solutions suitable to a given condition of decision making using a rule-based expert system. The expert system consists of a knowledge base of supplier selection solutions and an "if-then" rule-based inference engine. The knowledge base contains information about options and their consistency for seven characteristics of 20 supplier selection solutions chosen from articles published in SCIE journals since 2010. In the second phase, the model computes the potential suppliers' general performance indices using a technique for order preference by similarity to ideal solution (TOPSIS) based on their scores obtained by applying the suggested solutions. In the third phase, the model computes their risk indices using a TOPSIS based on their historical and predicted scores obtained by applying a risk evaluation algorithm. The evaluation algorithm deals with seven types of supply risk that significantly affect supplier's performance and eventually influence buyer's production plan. In the fourth phase, the model selects Pareto optimal suppliers based on their general performance and risk indices. An example demonstrates the implementation of the proposed model. The proposed model provides supply chain managers with a practical tool to effectively select best suppliers while considering supply risks as well as the general performance.

The Characteristics of the Milling Tool Deflection According to the Variation of Helix Angle (헬릭스각의 변화에 따른 밀링공구의 변위 특성 연구)

  • Maeng, Min-Jae;Chung, Joon-Ki
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.28 no.6
    • /
    • pp.860-866
    • /
    • 2004
  • In the end milling operation the deflection of the cutter is an important factor affecting the accuracy of machining, with implications on the selection of cutting parameters and economics of the operation. Several studies were devoted to the end mill deflection and its effects, notably, providing a useful insight into the problem. Although the deflection affects adversely the accuracy, the flexibility of the cutter is beneficial in attenuating the overload in a sudden transient situation, as well as in attenuating chatter. The deflection of the end mill was studied both experimentally with strain gauge, tool dynamometer, laser measuring apparatus and on a finite element model of the cutting using ANSYS software. The deflection of machining tool with various helix angles was studied with FEM simulation and experiment. ANSYS analysis performed on the finite element model of the end mill provides deflection results which agree within 15.0% with the experimental ones.