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A Study on Analysis and DMAIC Preventive Operations for Cargo Handling Accidents In Inchon Port (6시그마 기법을 적용한 인천항 항만하역 재해예방 대책에 관한 연구)

  • Nam Young Woo;Lee Chang Ho
    • Proceedings of the Safety Management and Science Conference
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    • 2005.05a
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    • pp.199-212
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    • 2005
  • Many countries of the world is driving forward development of large-scale hub port. They are now pushing ahead with setting up of effective marketing strategies to survive in keen competitions of the 21st century port industry. The port is of ever increasing importance for the bridge connecting sea and road transportation in handling international cargoes. The port, differently from general working places, is a closed area required for security, customs, and quarantine procedures. The loading and unloading is being done differently by ports, cargoes, and ships. To do loading and unloading, a lot of equipment and different types of labor are required, which flow is complicated and safe management is essential. As above mentioned the port is very unique and very deteriorated working place in its working environment. The purpose of this study is to propose ways to reduce and prevent from port accidents. As first step to do this, we have collected 923 accidents happened at Incheon Port during the period of 1994 to 2003. We have thoroughly analyzed characteristics, harmfulness, and risk of the loading/unloading they have done, as well as the accident frequency and relationship between the accidents. As second step to further analyze, We have employed DMAIC technology, an advanced process of 6 sigma presently in spotlight as the best program for management innovation. This analysis results in recognition of important accident characteristics, causes and effects analysis, critical causes of accident, and suggestions to decrease accidents.

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Nonlinear time-varying analysis algorithms for modeling the behavior of complex rigid long-span steel structures during construction processes

  • Tian, Li-Min;Hao, Ji-Ping
    • Steel and Composite Structures
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    • v.18 no.5
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    • pp.1197-1214
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    • 2015
  • There is a great difference in mechanical behavior between design model one-time loading and step-by-step construction process. This paper presents practical computational methods for simulating the structural behavior of long-span rigid steel structures during construction processes. It introduces the positioning principle of node rectification for installation which is especially suitable for rigid long-span steel structures. Novel improved nonlinear analytical methods, known as element birth and death of node rectification, are introduced based on several calculating methods, as well as a forward iteration of node rectification method. These methods proposed in this paper can solve the problem of element's 'floating' and can be easily incorporated in commercial finite element software. These proposed methods were eventually implemented in the computer simulation and analysis of the main stadium for the Universiade Sports Center during the construction process. The optimum construction scheme of the structure is determined by the improved algorithm and the computational results matched well with the measured values in the project, thus indicating that the novel nonlinear time-varying analysis approach is effective construction simulation of complex rigid long-span steel structures and provides useful reference for future design and construction.

A Study on Analysis and DMAIC Preventive Operations for Cargo Handling Accidents In Inchon Port (6시그마 기법을 적용한 인천항 항만하역 재해예방 대책에 관한 연구)

  • Nam Young Woo;Lee Chang Ho
    • Journal of the Korea Safety Management & Science
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    • v.7 no.2
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    • pp.13-27
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    • 2005
  • Many countries of the world is driving forward development of large-scale hub port. They are now pushing ahead with setting up of effective marketing strategies to survive in keen competitions of the 21st century port industry. The port is of ever increasing importance for the bridge connecting sea and road transportation in handling international cargoes. The port, differently from general working places, is a closed area required for security, customs, and quarantine procedures. The loading and unloading is being done differently by ports, cargoes, and ships. To do loading and unloading, a lot of equipment and different types of labor are required, which flow is complicated and safe management is essential. As above mentioned the port is very unique and very deteriorated working place in its working environment. The purpose of this study is to propose ways to reduce and prevent from port accidents. As first step to do this, we have collected 923 accidents happened at Incheon Port during the period of 1994 to 2003. We have thoroughly analyzed characteristics, harmfulness, and risk of the loading/unloading they have done, as well as the accident frequency and relationship between the accidents. As second step to further analyze, We have employed DMAIC technology, an advanced process of 6 sigma presently in spotlight as the best program for management innovation. This analysis results in recognition of important accident characteristics, causes and effects analysis, critical causes of accident, and suggestions to decrease accidents.

Diversity and Bioactive Potential of Culturable Fungal Endophytes of Medicinal Shrub Berberis aristata DC.: A First Report

  • Sharma, Supriya;Gupta, Suruchi;Dhar, Manoj K.;Kaul, Sanjana
    • Mycobiology
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    • v.46 no.4
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    • pp.370-381
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    • 2018
  • Bioactive natural compounds, isolated from fungal endophytes, play a promising role in the search for novel drugs. They are an inspiring source for researchers due to their enormous structural diversity and complexity. During the present study fungal endophytes were isolated from a well-known medicinal shrub, Berberis aristata DC. and were explored for their antagonistic and antioxidant potential. B. aristata, an important medicinal shrub with remarkable pharmacological properties, is native to Northern Himalayan region. A total of 131 endophytic fungal isolates belonging to eighteen species and nine genera were obtained from three hundred and thirty surface sterilized segments of different tissues of B. aristata. The isolated fungi were classified on the basis of morphological and molecular analysis. Diversity and species richness was found to be higher in leaf tissues as compared to root and stem. Antibacterial activity demonstrated that the crude ethyl acetate extract of 80% isolates exhibited significant results against one or more bacterial pathogens. Ethyl acetate extract of Alternaria macrospora was found to have potential antibacterial activity. Significant antioxidant activity was also found in crude ethyl acetate extracts of Alternaria alternata and Aspergillus flavus. Similarly, antagonistic activity of the fungal endophytes revealed that all antagonists possessed inhibition potential against more than one fungal pathogen. This study is an important step towards tapping endophytic fungal diversity for bioactive metabolites which could be a step forward towards development of novel therapeutic agents.

Machine Layout Decision Algorithm for Cell Formation Problem Using Self-Organizing Map (자기조직화 신경망을 이용한 셀 형성 문제의 기계 배치순서 결정 알고리듬)

  • Jeon, Yong-Deok
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.42 no.2
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    • pp.94-103
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    • 2019
  • Self Organizing Map (SOM) is a neural network that is effective in classifying patterns that form the feature map by extracting characteristics of the input data. In this study, we propose an algorithm to determine the cell formation and the machine layout within the cell for the cell formation problem with operation sequence using the SOM. In the proposed algorithm, the output layer of the SOM is a one-dimensional structure, and the SOM is applied to the parts and the machine in two steps. The initial cell is formed when the formed clusters is grouped largely by the utilization of the machine within the cell. At this stage, machine cell are formed. The next step is to create a flow matrix of the all machine that calculates the frequency of consecutive forward movement for the machine. The machine layout order in each machine cell is determined based on this flow matrix so that the machine operation sequence is most reflected. The final step is to optimize the overall machine and parts to increase machine layout efficiency. As a result, the final cell is formed and the machine layout within the cell is determined. The proposed algorithm was tested on well-known cell formation problems with operation sequence shown in previous papers. The proposed algorithm has better performance than the other algorithms.

Seismic and collapse analysis of a UHV transmission tower-line system under cross-fault ground motions

  • Tian, Li;Bi, Wenzhe;Liu, Juncai;Dong, Xu;Xin, Aiqiang
    • Earthquakes and Structures
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    • v.19 no.6
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    • pp.445-457
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    • 2020
  • An ultra-high voltage (UHV) transmission system has the advantages of low circuitry loss, high bulk capacity and long-distance transmission capabilities over conventional transmission systems, but it is easier for this system to cross fault rupture zones and become damaged during earthquakes. This paper experimentally and numerically investigates the seismic responses and collapse failure of a UHV transmission tower-line system crossing a fault. A 1:25 reduced-scale model is constructed and tested by using shaking tables to evaluate the influence of the forward-directivity and fling-step effects on the responses of suspension-type towers. Furthermore, the collapse failure tests of the system under specific cross-fault scenarios are carried out. The corresponding finite element (FE) model is established in ABAQUS software and verified based on the Tian-Ma-Qu material model. The results reveal that the seismic responses of the transmission system under the cross-fault scenario are larger than those under the near-fault scenario, and the permanent ground displacements in the fling-step ground motions tend to magnify the seismic responses of the fault-crossing transmission system. The critical collapse peak ground acceleration (PGA), failure mode and weak position determined by the model experiment and numerical simulation are in relatively good agreement. The sequential failure of the members in Segments 4 and 5 leads to the collapse of the entire model, whereas other segments basically remain in the intact state.

Translation and psychometric evaluation of the Korean version of the fertility awareness and attitudes towards parenthood questionnaire

  • Shin, Hyewon;Hong, Minjoo;Jo, Minjeong;Lee, Jungmin
    • Child Health Nursing Research
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    • v.27 no.3
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    • pp.256-265
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    • 2021
  • Purpose: This study presents a translation, cultural adaptation, and psychometric evaluation of two instruments of the Fertility Awareness and Attitudes Towards Parenthood (FAAP) questionnaire (Conditions and Life changes) for use in South Korea. Methods: This methodological study included 166 university students for psychometric evaluation in the sixth step. The first five steps included forward translation, backward translation, committee review, assessment of content validity, and a pre-test. In the sixth step, psychometric properties, including internal consistency, construct validity, and criterion validity, were evaluated. Exploratory factor analysis and confirmatory factor analysis were conducted to identify the structure of the tool and to assess its validity. Results: The Korean version showed acceptable internal consistency. Cronbach's α was .73 for FAAP-Conditions and .83 for FAAP-Life changes. FAAP-Conditions showed a four-factor structure (social conditions, relationship with partner, external environment, and child-rearing support) and FAAP-Life changes had a two-factor structure (reward and burden). In the confirmatory analysis, CMIN/DF, TLI, IFI, SRMR, CFI, and RMSEA were satisfactory. Conclusion: This study provided preliminary evidence of the acceptability, reliability, and validity of the Korean version of the FAAP questionnaire in university students in South Korea. Nonetheless, further evaluation among Korean young adults is warranted to validate this instrument.

Total Management System for Earth Retaining Structures Using Observational Method (지반굴착 흙막이공의 정보화시공 종합관리 시스템)

  • 오정환;조철현;김기웅;백영식
    • Journal of the Korean Geotechnical Society
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    • v.18 no.2
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    • pp.51-64
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    • 2002
  • Observational results of ground movement during the construction were very different from those predicted during the analysis of design step because of the uncertainty of the numerical analysis modelling, the soil parameter, and the condition of a construction field, etc., however accurately numerical analysis method was applied for prediction of ground movement per the excavation step. Therefore, the management system through the construction field measurement should be achieved for grasping the situation during the excavation. Until now, the measurement system restricted by 'Absolute Value Management system'analyzing only the stability of present step has been executed. So, it was difficult to expect the prediction of ground movement fur the next excavation step. In this situation, this study developed 'The Management system TOMAS-EXCAV'consisted of 'Absolute value management system'analyzing the stability of present step and 'Prediction management system'expecting the ground movement of next excavation step and analyzing the stability of next excavation step by 'Back Analysis'. TOMAS-EXCAV could be applied to all the uncertainty of earth retaining structures analysis by connecting 'Forward analysis program'and 'Back analysis program'and optimizing the main design variables using SQP-MMFD optimization method through measurement results. The applicability of TOMAS-EXCAV was confirmed by back analysis selecting two earth retains construction fields.

The Development of an Instrument for Scientific Attitudes in School, Home and Social Situations and Selection of Scientific Attitude Elements (과학적 태도 요소 선정 및 학교, 가정, 사회 상황을 고려한 과학적 태도 측정 도구 개발)

  • Song, Young-Wook;Kim, Beom-Ki
    • Journal of The Korean Association For Science Education
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    • v.30 no.4
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    • pp.375-388
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    • 2010
  • The purpose of this study was to develop the instrument for scientific attitudes in school, home and social situations and select the important elements of scientific attitudes. Looking into the elements of scientific attitudes in national and international research, the important elements of scientific attitudes students should have were selected as follows: Openness, objectivity, continuousness, criticalness, prudence, volunteerism, honesty, preparedness, collaboration, and curiosity. To develop the valid instrument of scientific attitudes, we moved forward with the step of making preliminary questions, the judgment step, and the validation examination step. Based on the elements of scientific attitudes and school, family, and social situations, the instrument of the scientific attitudes was developed. We discovered that Middle school students' scientific attitudes, according to their grade levels, appear to be significantly lower than those in the 7th graders and 9th graders. The scientific attitudes in school, home and social situation appeared high in order of society, home, and school. It appeared that there were no differences by gender.

Relationships Between Cognitive Function and Gait-Related Dual-Task Interference After Stroke

  • Kim, Jeong-Soo;Jeon, Hye-Seon;Jeong, Yeon-Gyu
    • Physical Therapy Korea
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    • v.21 no.3
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    • pp.80-88
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    • 2014
  • Previous studies have reported that decreased cognitive ability has been consistently associated with significant declines in performance of one or both tasks under a dual-task walking condition. This study examined the relationship between specific cognitive abilities and the dual-task costs (DTCs) of spatio-temporal gait parameters in stroke patients. The spatio-temporal gait parameters were measured among 30 stroke patients while walking with and without a cognitive task (Stroop Word-Color Task) at the study participant's preferred walking speed. Cognitive abilities were measured using Computerized Neuropsychological Testing. Pearson's correlation coefficients (r) were calculated to quantify the associations between the neuropsychological measures and the DTCs in the spatio-temporal gait parameters. Moderate to strong correlations were found between the Auditory Continuous Performance test (ACPT) and the DTCs of the Single Support Time of Non-paretic (r=.37), the Trail Making A (TMA) test and the DTCs of Velocity (r=.71), TMA test and the DTCs of the Step Length of Paretic (r=.37), TMA test and the DTCs of the Step Length Non-paretic (r=.36), the Trail Making B (TMB) test and the DTCs of Velocity (r=.70), the Stroop Word-Color test and the DTCs of Velocity (r=-.40), Visual-span Backward (V-span B) test and the DTCs of Velocity (r=-.41), V-span B test and the DTCs of the Double Support Time of Non-paretic (r=.38), Digit-span Forward test and the DTCs of the Step Time of Non-paretic (r=-.39), and Digit-span Backward test and the DTCs of the Single Support Time of Paretic (r=.36). Especially TMA test and TMB test were found to be more strongly correlated to the DTCs of gait velocity than the other correlations. Understanding these cognitive features will provide guidance for identifying dual- task walking ability.