• Title/Summary/Keyword: reliability factors

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An Efficient Method for Allocating Storage Yard for Container Terminal (컨테이너 터미널의 장치장 활용 방안에 관한 연구)

  • Song Yong-Seok;Nam Ki-Chan;Yoo Ju-Young;Kim Tae-Won
    • Journal of Navigation and Port Research
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    • v.30 no.3 s.109
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    • pp.203-209
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    • 2006
  • Maritime transport has been occupying the biggest part of the container transportation market. With regard to container terminal management, the planning technology and the space allocation system on the yard are very significant factors to secure the stability of ship and to ensure the reliability of schedules of ship throughout keeping barycenter of vessel by right loading and fast handling of cargoes. The purposes of this paper are to illustrate the existing yard management systems such as Grouping method and Random Grounding method, and then to evaluate and compare the efficiency of yard availability between the existing management system(Grouping method) and Random Grouping which uses the forecasted inbound cargo volume at the gate by Time Base Operation.

Alternatives for Entering into the Chinese Market by Smaller-Sized Korean Logistics Enterprises (우리나라 중소물류기업의 중국진출 활성화 방안)

  • Cho, Sam-Hyun
    • Journal of Navigation and Port Research
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    • v.36 no.10
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    • pp.889-893
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    • 2012
  • The growth of Chinese logistics market has brought many logistics enterprises enter into the chinese market. The purpose of this study is to suggest some alternatives for activating enter into chinese market for smaller-sized korean logistics enterprise. First of all, in order to achieve such a purpose, factors for activation through literature survey and previous studies are analyzed. After that, questionnaire survey are carried out. Also factor analysis and reliability test based on the questionnaire results are performed. Main findings are suggested as followings. First, in order to activate entering the chinese market, it is drawn out that possessing of logistics infrastructure and understanding of culture of chinese relationship are most important. Second, market information and reform of management system, inspection and customs clearance are suggested as less important.

Evaluation of AIS-TWR for Maritime Asynchronous R-mode (해사업무용 비동기식 R-mode를 위한 AIS-TWR 성능 평가)

  • Shim, Woo-Seong;Lee, Sang-Jeong
    • Journal of Navigation and Port Research
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    • v.41 no.3
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    • pp.87-92
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    • 2017
  • To enhance the reliability and/or resilience of the PNT service included in the e-Navigation strategy of the IMO, the evaluation of the AIS-TWR method for the asynchronous R-mode for maritime service, which is available even in the absence of the GNSS, is described. For the AIS-TWR, which is capable of ranging through message exchange even without high precision synchronization, the operation scenario and the error factors according to the AIS system specifications are proposed and analyzed. Cramer-Rao Lower Bound is presented for the performance evaluation of the AIS-TWR algorithm. A simulation by AIS-TWR method of two AIS systems in a 3 km static environment shows estimation error of about 41m compared to the real value..

A Review of Human Element Issues of Remote Operators on Maritime Autonomous Surface Ships (자율운항선박의 개발 및 운용을 위한 육상 운항사의 인적요인 이슈 고찰)

  • Kim, Hong-Tae;Yang, Young-Hoon
    • Journal of Navigation and Port Research
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    • v.43 no.6
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    • pp.395-402
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    • 2019
  • The development and operation of the MASS (Maritime Autonomous Surface Ship) is being actively discussed for more efficient and safer maritime transportation solutions. The autonomous navigation technology has positive aspects such as the prevention of marine accidents, improvement of fuel efficiency of ships and cost reduction, and negative aspects such as job loss, task change, and security problems. It is expected that there will be new human element issues such as the situation awareness of remote operators, because the shore-based control will be conducted when fully autonomous ships are in operation. In this paper, we consider major human element issues that should be factored in the development and operation of MASS, and suggest a method of HRA (Human Reliability Analysis) for P IFs (Performance Influencing Factors) of the remote operators that are expected according to the shore-based control.

A Study on the Method of Combining Empirical Data and Deterministic Model for Fuel Failure Prediction (핵연료 파손 예측을 위한 경험적 자료와 결정론적 모델의 접합 방법)

  • Cho, Byeong-Ho;Yoon, Young-Ku;Chang, Soon-Heung
    • Nuclear Engineering and Technology
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    • v.19 no.4
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    • pp.233-241
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    • 1987
  • Difficulties are encountered when the behavior of complex systems (i.e., fuel failure probability) that have unreliable deterministic models is predicted. For more realistic prediction of the behavior of complex systems with limited observational data, the present study was undertaken to devise an approach of combining predictions from the deterministic model and actual observational data. Predictions by this method of combining are inferred to be of higher reliability than separate predictions made by either model taken independently. A systematic method of hierarchical pattern discovery based on the method developed in the SPEAR was used for systematic search of weighting factors and pattern boundaries for the present method. A sample calculation was performed for prediction of CANDU fuel failures that had occurred due to power ramp during refuelling process. It was demonstrated by this sample calculation that there exists a region of feature space in which fuel failure probability from the PROFIT model nearly agree with that from observational data.

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Evaluation of SELECT Model for the Quality Prediction of Water Released from Stratified Reservoir (성층화된 저수지의 방류수 수질예측을 위한 SELECT 모델의 적용성 검토)

  • Lee, Heung Soo;Chung, Se Woong;Shin, Sang Il;Choi, Jung Kyu;Kim, Yu Kyung
    • Journal of Korean Society on Water Environment
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    • v.23 no.5
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    • pp.591-599
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    • 2007
  • The quality of water released from a stratified reservoir is dependent on various factors such as the location and shape of intake facility, structure of reservoir stratification, profile of water quality constituent, and withdrawal flux. Sometimes, selective withdrawal capabilities can provide the operational flexibility to meet the water quality demands both in-reservoir and downstream. The objective of this study was to evaluate the performance of a one-dimensional reservoir selective withdrawal model (SELECT) as a tool for supporting downstream water quality management for Daecheong and Imha reservoirs. The simulated water quality variables including water temperature, dissolved oxygen (DO), conductivity, turbidity were compared with the field data measured in tailwater. The model showed fairly satisfactory results and high reliability in simulating observations. The coefficients of determinant between simulated and observed turbidity values were 0.93 and 0.95 for Daecheong and Imha reservoirs, respectively. The outflow water quality was significantly influenced by water intake level under fully stratified condition, while the effect of intake amount was minor. In conclusion, the SELECT is simple but effective tool for supporting downstream water quality prediction and management for both reservoirs.

Effect of Storytelling Marketing in Publishing Company: Focused on Facebook Case (출판사의 스토리텔링 마케팅 효과 연구: 페이스북을 중심으로)

  • Bae, Jun-Young;Oh, Kyung-Soo
    • The Journal of the Korea Contents Association
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    • v.15 no.10
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    • pp.92-104
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    • 2015
  • Many publishing companies go to storytelling marketing through facebook in these days. Because storytelling marketing through facebook is thought for publishing company as useful marketing method in accordance with the increase of social media user. Thus, this study classified storytelling marketing type by episode, experience, anniversary, information and also analyzed the difference of cognitive reaction, emotional reaction and variables which effect to purchase intention according to each storytelling marketing type. As the results, anniversary type and information type got more positive reaction from responses rather than episode type and experience type with respect to likability, reliability, informativeness, engagement. Also engagement, likability, informativeness are revealed as major variables which effect to purchase intention of each storytelling type. Thus, storytelling marketing of publishing company through facebook need to focus on anniversary type and information type. And it is important to combine naturally the information regarding to book that publishing company want to sell with the fun, pleasure factors that story can give.

Female Customers' Trust on Internet Stores and its Relationships with Service Quality and Loyalty (인터넷 상점에 대한 여성고객의 신뢰와 서비스 품질$\cdot$고객 충성도 간의 관계)

  • Min Dong-Kwon
    • The Journal of Information Systems
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    • v.14 no.2
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    • pp.293-317
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    • 2005
  • Female customers form a major customer group for Internet shopping and their trust on Internet stores seems to be significantly related with their transactions. This paper focuses on female customers' trust on Internet stores, hypothesizing that online service quality has a positive impact on trust and that trust, in turn, together with service quality has a positive effect on loyalty. We investigate trust from three dimensions(benevolence, integrity, and ability) and at the same time, unlike existing research, treat service quality to have five dimensions (intangibles, reliability, responsiveness, assurance, and empathy) as known in SERVQUAL(Parasuraman et al., 1988). Survey data is obtained from the female college student sample. Our research model is justified in terms of construct validity, internal consistency, and goodness of fit. Research hypotheses are tested using SEM(Structural Equation Modeling). The results are as follows: First, assurance and empathy dimensions of service quality have significant impacts on benevolence/integrity dimension of trust. Second, out of the five service quality dimensions, only assurance has a positive effect on ability dimension of trust. Third, assurance dimension of service quality and ability dimension of trust are positively related with customer loyalty. The most important factors for female customers' loyalty are found to be assurance(service quality) and ability(trust). The significance of assurance is in line with findings from existing research. But its relationship with the trust dimensions is uncovered in this research, and the only dimension that impacts on ability is assurance. We find that female customers build trust about internet stores based on their ability rather than on their benevolence/integrity and that the female customers' perception on the internet stores' ability can be improved by higher service quality from the aspect of assurance. Importantly enough, these findings offer practical guidelines to Internet stores to boost female customers' loyalty.

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A Study of the Relationship between the Leadership Style of the Head Nurse and Nurses과 Burnout Level (수간호원의 리더쉽 유형과 간호원의 소진 (Burnout) 경험 정도와의 관계)

  • 김화실
    • Journal of Korean Academy of Nursing
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    • v.14 no.1
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    • pp.21-33
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    • 1984
  • The purpose of this study was to define the relationship between the leadership style of head nurses and the burnout level of nurses by taking into consideration the factors which influence the level of burnout and which show how burnout varies according to the leadership style of lead nurses. The subjects of the survey were 355 ward nurses and their 48 head nurses working in five university hospitals in Seoul. The nurses were surveyed by means of a questionnaire from Sept. 22 though Sept. 29, 1983. The Leadership Scale devised by Fleishman, and modified by Lee, and the Burnout Scale developed by Pines et al, and adapted to the Korean situation by Peek, were used as a basis of ;his survey This researcher subjected the questionnaire to a pre-test and to an internal reliability consistency test through item analysis. For the purpose of analysis of the data, the general characteristics were set at Mean and the general characteristics of head nurses in relation to the level of burnout of nurses was analysed by the Pearson Correlation Coefficient. The relation between head nurses' general characteristics 3nd leadership style, the relation between nurses' general characteristics and level of burnout and the level of burnout of nurses according to the different style of leadership of head nurses were analysed by ANOVA. A summary of the results of the study is as follows. 1. Hypothesis:“That the burnout level of the nurse will be different according to the leadership style of the head nurse”was supported. 2. Analysis of the relationship between the head nurse's general characteristics and the leadership style of the head nurse showed that the leadership style of the head nurse was not related to age and experience as head nurse. 3. Analysis of the relationship of nurses' burnout levels to general characteristics of nurses showed statistically significant differences in burnout levels according to working departments, expected working period and reasons for selecting nursing as a profession. Also, the burnout level of nurses was negatively related to the head nurse's age and experience as a head nurse.

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Turkish Adolescent Perceptions about the Effects of Water Pipe Smoking on their Health

  • Cakmak, Vahide;Cinar, Nursan
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.18
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    • pp.8645-8652
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    • 2016
  • Background: Consumption of tobacco in the form of a water pipe has recently increased, especially among young people. This study aimed to develop a scale which would be used in order to detect perceptions about the effects of water pipe smoking on health and to test its validity and reliability. Our scale named "a scale of perception about the effects of water pipe smoking on health" was developed in order to detect factors effecting the perception of adolescents about the effects of water pipe smoking on health. Materials and Methods: The sample consisted of 150 voluntary students in scale development and 750 voluntary students in the study group. Data were collected via a questionnaire prepared by researchers themselves and 5-pont Likert scale for "a scale of perception about the effects of water pipe smoking on health" which was prepared through the literature. Data evaluation was carried out on a computer with SPSS. Results: The findings of the study showed that "a scale of perception about the effects of water pipe smoking on health" was valid and reliable. Total score average of the adolescents participated in the study was $58.5{\pm}1.25$. The mean score of the ones who did not smoke water pipe ($60.1{\pm}11.7$) was higher than the mean score of the ones who smoked water pipe ($51.6{\pm}13.8$), the difference being statistically significant. Conclusions: It is established that "a scale of perception about the effects of water pipe smoking on health" was a reliable and valid measurement tool. It is also found out that individuals who smoked a water pipe had a lower level of perception of water pipe smoking effects on health than their counterparts who did not smoke a water pipe.