• Journal of muscle and joint health
• /
• v.22 no.1
• /
• pp.40-47
• /
• 2015

Purpose: The purpose of this study was to identify factors influencing on performance of preventive actions to be exposed to infection in emergency nurses. Methods: Participants were 200 emergency nurses working in a regional emergency medical center, 4 local emergency medical centers, and 5 local emergency medical facilities in B city. The data were analyzed with descriptive statistics, independent t-test, ANOVA, Scheff$\acute{e}$'s test, Pearson's correlation coefficients, and stepwise multiple regression analysis using SPSS/WIN 21.0 programs. Results: There was no difference in performance of preventive actions to be exposed to infection by socio-demographic and job-related characteristics. The results of stepwise multiple regression analysis showed that levels of perception of preventive actions to be exposed to infection (${\beta}$=.40, p<.001) and protective environment on exposure to infection (${\beta}$=.22, p<.001) were significantly associated with performance of preventive actions, explaining 26.3% of the variance. Conclusion: In conclusion, improving performance of preventive actions to be exposed to infection is important to protect emergency nurses from exposure to infection. Thus, efforts to enhance protective environment on exposure to infection and to improve perceptions of preventive actions to be exposed to infection are necessary to improve the performance of preventive actions in emergency nurses.

• International Journal of Control, Automation, and Systems
• /
• v.3 no.spc2
• /
• pp.334-340
• /
• 2005

Based on the stability margin provided by the EEAC, the unstable contingencies can be classified into sets according to their unstable modes. This two-part paper develops a globally optimal algorithm for transient stability control to coordinate preventive actions and emergency actions. In the first part, an algorithm is proposed for a set of contingencies having identical unstable modes. Instead of iterations between discrete emergency actions and continuous preventive actions, the algorithm straightforwardly searches for a globally optimal solution. The procedure includes assessing a set of insufficient emergency schemes identified by the EEAC; calculating the related preventive actions needed for stabilizing the system; and selecting the scheme with the minimum overall costs. Simulations on a Chinese power system highlight its excellent performance. The positive results obtained are explained by analogizing settlements for 0-1 knapsack problems using the multi-points greedy algorithm.

• International Journal of Control, Automation, and Systems
• /
• v.3 no.spc2
• /
• pp.341-345
• /
• 2005

Part-I of this two-part paper develops an optimal algorithm for transient stability control to coordinate the preventive actions and emergency actions for a subset of contingencies with an identical unstable mode. In this portion, several subsets of contingencies having dissimilar unstable modes are dealt with. Preventive actions benefiting a subset of contingencies may go against the stability of others, thus coordination among the optimal schemes for individual subsets is necessary. The coordination can be achieved by replacing some preventive actions with contingency-specified emergency actions. It is formulated as a classical model of economic dispatch with stability constraints and stability control costs. Such an optimal algorithm is proposed based on the algorithm in Part-I of the paper and is verified by simulations on a Chinese power system.

• Journal of Korean society of Dental Hygiene
• /
• v.9 no.2
• /
• pp.45-56
• /
• 2009

The purposes of this study were to investigate the relationships between the degree of physical pain and the knowledge and preventive actions of musculoskeletal diseases among dental hygiene students with a potential risk of contracting those diseases and thus to help them prevent them. A survey was taken among 207 sophomores and juniors specializing in dental hygiene at S1 and S2, Gyeonggi Province in the area of physical pain, knowledge of musculoskeletal diseases, and preventive actions against them. The findings were as follows: 1. The mean scores of the sophomore in the knowledge of musculoskeletal diseases were $6.20{\pm}2.21$, and those of the juniors were $6.72{\pm}2.29$. The mean scores of the sophomores and juniors in the preventive actions against musculoskeletal diseases were $22.50{\pm}2.37$ and $22.29{\pm}3.01$, respectively. 2. The subjects displayed severe physical pain in the lower back, shoulder, and neck in the descending order and medium physical pain in the neck, shoulder, and lower back in the descending order. 3. The higher level knowledge of musculoskeletal diseases they had, the less physical pain they felt. And there were significant differences among the shoulder, lower back, hip, ankle, and foot. 4. There were relationships between physical pain and the preventive actions against musculoskeletal diseases in "placing the hands at the height of the elbows during treatment", "reducing such positions as bending and extending during treatment", "narrowing the distance with the patient", "taking regular breaks during treatment for recovery", "trying not to incline the neck, back, arm, and wrist as much as possible", and "trying to keep the torso in the neutral position." 5. As for the education about musculoskeletal diseases, 74 sophomores(88.10%) and 102 juniors(89.74%) answered they received no such education. The results suggest that there should be some instructions to help dental hygiene students practice the preventive actions against musculoskeletal diseases and further prevention programs against those diseases.

• The Korean Journal of Emergency Medical Services
• /
• v.22 no.1
• /
• pp.21-34
• /
• 2018

Purpose: The purpose of this study was to investigate the influencing factors of prevention practices against infection exposure among emergency medical technicians (EMTs) in emergency rooms. Methods: A self-reported questionnaire was filled out by 100 EMTs in emergency rooms from June 1 to August 31, 2017. The questionnaire consisted of items concerning the defensive environment for the prevention of infection exposure, perception of preventive behavior, and degree of performance of preventive actions against infection based on a five-point Likert scale. Data were analyzed by descriptive statistics, ${\chi}^2$ test, ANOVA, Pearson's correlation coefficients, and linear regression. Results: The defensive environment for the prevention of infection exposure was 4.12. The perception of preventive action was 4.71, and the degree of performance of preventive actions against infection was 4.54. There was a significant relationship between the degree of performance of preventive actions against infectious exposures and the degree of perception of preventive behavior(r=.506, p=.01) and prevention of infectious exposure(r=.506, p=.01). The protective environment(B=.360, t=3.236, p=.002) and perceived level (B=.904, t=4.662, p=.000) were influenced by the degree of prevention of infection exposure. Conclusion: It is important to manage the protection environment for infection exposure prevention and to enhance the awareness of infection prevention actions against infection exposure among the EMTs in emergency rooms.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.41 no.2
• /
• pp.24-31
• /
• 2018

As a system complexity increases and technology innovation progresses rapidly, leasing the equipment is considered as an important issue in many engineering areas. In practice, many engineering fields lease the equipment because it is an economical way to lease the equipment rather than to own the equipment. In addition, as the maintenance actions for the equipment are costly and need a specialist, the lessor is responsible for the maintenance actions in most leased contract. Hence, the lessor should establish the optimal maintenance strategy to minimize the maintenance cost. This paper proposes two periodic preventive maintenance policies for the leased equipment. The preventive maintenance action of policy 1 is performed with a periodic interval, in which their intervals are the same until the end of lease period. The other policy is to determine the periodic preventive maintenance interval minimizing total maintenance cost during the lease period. In addition, this paper presents two decision-making models to determine the preventive maintenance strategy for leased equipment based on the lessor's preference between the maintenance cost and the reliability at the end of lease period. The structural properties of the proposed decision-making model are investigated and algorithms to search the optimal maintenance policy that are satisfied by the lessor are provided. A numerical example is provided to illustrate the proposed model. The results show that a maintenance policy minimizing the maintenance cost is selected as a reasonable decision as the lease term becomes shorter. Moreover, the frequent preventive maintenance actions are performed when the minimal repair cost is higher than the preventive maintenance cost, resulting in higher maintenance cost.

• Computers and Concrete
• /
• v.17 no.4
• /
• pp.499-521
• /
• 2016

In this paper, a probabilistic- and finite element-based approach to evaluate and predict the lifetime performance of reinforced concrete (RC) bridges undergoing various maintenance actions is proposed with the time-variant system reliability being utilized as a performance indicator. Depending on their structural state during the degradation process, the classical maintenance actions for RC bridges are firstly categorized into four types: Preventive type I, Preventive type II, Strengthening and Replacement. Preventive type I is used to delay the onset of steel corrosion, Preventive type II can suppress the corrosion process of reinforcing steel, Strengthening is the application of various maintenance materials to improve the structural performance and Replacement is performed to restore the individual components or overall structure to their original conditions. The quantitative influence of these maintenance types on structural performance is investigated and the respective analysis modules are written and inputted into the computer program. Accordingly, the time-variant system reliability can be calculated by the use of Monte Carlo simulations and the updated the program. Finally, an existing RC continuous bridge located in Shanghai, China, is used as an illustrative example and the lifetime structural performance with and without each of the maintenance types are discussed. It is felt that the proposed approach can be applied to various RC bridges with different structural configurations, construction methods and environmental conditions.

• Smart Structures and Systems
• /
• v.15 no.3
• /
• pp.609-625
• /
• 2015

Management of infrastructure stock is essential in sustainability of society, and its analysis and optimization are studied in the light of control system modeling in this paper. At the first part of the paper, cost of stock management is analyzed based on macroscopic statistics on infrastructure stock and economical growth. Stock management burden relative to economy is observed to become larger at low economic growth periods in developed economies. Then, control system modeling of stock management is introduced and by augmenting maintenance actions as control input, dynamic behavior of stock is simulated and compared with existing time history statistics. Assuming steady state conditions, applicability of the model to cross sectional data is also demonstrated. The proposed model is enhanced so that both preventive and corrective maintenance can be included as system inputs, i.e., feedforward and feedback control inputs. Optimal management strategy to achieve specified deteriorated stock level with minimal cost, expressed in terms of preventive and corrective maintenance actions, is derived based on estimated parameter values for corrosion of steel bridges. Relative cost effectiveness of preventive maintenance is shown when target deteriorated stock level is lower.

• IE interfaces
• /
• v.15 no.3
• /
• pp.286-296
• /
• 2002

Products which are sold with warranty, preventive maintenance actions by manufacturers and/or buyers have an impact on the total costs for both parties. In this paper, we develop the models to study the expected warranty cost for products with free repairable warranty with three types of discrete preventive maintenance. We deal with by utilizing the concept that preventive maintenance reduces the virtual age of the system. We assume that the maintenance planning horizon can be segmented into k discrete and equally sized periods. In such a scenario, numerical examples are presented.

• Journal of Technologic Dentistry
• /
• v.36 no.4
• /
• pp.257-266
• /
• 2014

Purpose: This report intend to provide basic materials of Musculoskeletal diseases prevention program development and preventive measures establishing by surveying Musculoskeletal symptoms. Musculoskeletal disease and Musculoskeletal disease prevention act about dental technician in Daegu. Methods: From October. 2012 to November. 2012 by conducting self - survey using questionnaire and use unit490 final analysis data. Results: In dental Technicians, as the musculoskeletal symptoms back or waist pain rate appear such as 28.2% and as the musculoskeletal disorders, the shoulder region pain complaint rate appear highly such as 87.4%. Musculoskeletal disease prevention act was highly appeared man more than women, the married than the unmarried, over 10 years dental experience, fewer working hours per day, the average monthly income is greater regular medical check-up dental technician than technician who do not. As working environment, In case working in laboratory whch dust is well ventilated and with a barrier, Musculoskeletal disease prevention act rate was highly appeared more than another technician who do not. Conclusion: We must prepare an effective preventive measures. To development Musculoskeletal disease prevention program suitable for dental technic working and make obliged to practice.