• Advances in concrete construction
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• v.1 no.1
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• pp.65-84
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• 2013

Electrical resistivity is a property associated with both the physical and chemical characteristics of concrete. It allows the evaluation of the greater or lesser difficulty with which aggressive substances penetrate the concrete's core before the dissolution of the passive film process and the consequent reinforcement's corrosion begin. This work addresses the capillary absorption of self-compacting concrete (SCC) with various types and contents of additions, correlating it with its electrical resistivity. To that effect, binary and ternary mixes of SCC were produced using fly ashes (FA) and limestone filler (LF). A total of 11 self-compactable mixes were produced: one with cement (C) only; three with C + FA in 30%, 60% and 70% substitution ratios; three with C + LF in 30%, 60% and 70% substitution ratios; four with C + FA + LF in combinations of 10-20%, 20-10%, 20-40% and 40-20% substitution ratios, respectively; and four reference mixes according to the LNEC E 464 specification, which refers to the NP EN 206-1 norm. The evaluation of the capillarity of the mixes produced was made through the determination of the water absorption by capillarity coefficient according to the LNEC E 393 specification. The electrical resistivity was evaluated using the European norm proposal presented by the EU-Project CHLORTEST (EU funded research Project under 5FP GROWTH programme) and based on the RILEM TC-154 EMC technical recommendation. The results indicate that SCC's capillarity is strongly conditioned by the type and quantity of the additions used. It was found that FA addition significantly improves some of the properties studied especially at older ages.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.11
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• pp.7635-7647
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• 2015

The purpose of this study is modeling nursing competencies and reasoning out the core competencies, the ability for 20% of important actions for nursing jobs which can manage the rest 80% so that the competency-based nursing curriculum can be developed. A literature review of the vast studies regarding competencies was done to understand the concepts of competency-based curriculum, competency, and nursing competencies, identifying the relationships among each nursing competency categorized in accordance with those concepts. An exemplified concept map of core competencies for the competency-based nursing curriculum is suggested based on a thorough review of various competency modeling methodologies. The core competencies consist of base competency (theoretical/practical nursing knowledge and skills), practical competency (clinical judgment, patient education, communication, etc.), and personality competency (leadership, sense of responsibility, cooperation, etc.). The circular relationship among them can remain consistent through self-directed learning and critical thinking. Therefore, a nurse who have those core competencies is a knowledge worker, a self-directed learner, and also an effective, professional communicator. Further studies which solidify the concept of nursing competencies should be done, as well as the feedback procedures which evaluate the program outcomes and then reflect the evaluation results in the curriculum should be followed continuously.

• Journal of Sensor Science and Technology
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• v.25 no.4
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• pp.264-270
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• 2016

Self-powered neutron detector (SPND) is a sensor to monitor a neutron flux proportional to a reactor power of the nuclear power plants. Since an SPND is usually installed in the reactor core and does not require additional outside power, it generates electrons itself from interaction between neutrons and a neutron-sensitive material called an emitter, such as rhodium and vanadium. This paper presents the simulations of the depletion sensitivity evaluations based on MCNP models of rhodium and vanadium SPNDs and light water reactor fuel assembly. The evaluations include the detail geometries of the detectors and fuel assembly, and the modeling of rhodium and vanadium emitter depletion using MCNP and ORIGEN-S codes, and the realistic energy spectrum of beta rays using BETA-S code. The results of the simulations show that the lifetime of an SPND can be prolonged by using vanadium SPND than rhodium SPND. Also, the methods presented here can be used to analyze a life-time of those SPNDs using various emitter materials.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.13 no.4
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• pp.295-300
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• 2015

The precise determination of the activity for each radionuclide in environmental samples requires the self-absorption correction factor. In this research, we derived the self-absorption correction factor for three p-type high purity germanium detectors using the Monte Carlo code MCNPX. These detectors have different characteristics such as crystal diameter, height and size of the core. We compared the calculated full-energy peak efficiency with the experimental value using a standard sample with $1g/m^3$ density and verified the modeling. We simulated the dependency of the full-energy peak efficiency on the 0.3, 0.6, 0.9, 1.0, 1.2 and $1.5g/m^3$ samples and obtained the corresponding self-absorption correction factor. The self-absorption correction factors calculated for the three detectors differ by less than 1% over most of the energy range and sample densities considered. This indicates that the self-absorption correction factors are independent of the crystal characteristics of HPGe detector.

• Korean Medical Education Review
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• v.25 no.2
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• pp.159-173
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• 2023

The purpose of this study was to develop and validate a competency tool for new nurses and to pilot-test it with new nurses. A Delphi survey was conducted to develop a competency tool, and a self-evaluation was conducted among new nurses who pilot-tested the finally derived competencies. The Delphi survey panel consisted of 18 people, including adjunct professors at the College of Nursing, nursing managers, and nurses with master's degrees. The Delphi survey asked about the validity of the competencies constructed in two rounds. After analyzing the Delphi results with mean, standard deviation, content validity ratio, degrees of convergence, and degrees of consensus, 12 core competencies and 36 enabling competencies were finally derived. The competencies consisted of clinical judgment and management (nine items), task competence (four items), patient orientation (five items), moral value orientation (three items), cooperation (two items), supply management (two items), professional development (three items), confidence (one item), self-control (two items), flexibility (two items), influence (one item), and nurturing others (two items). The finally derived competencies were pilot-tested with 229 new nurses who had worked for 2-12 months. The self-evaluation scores of new nurses were distributed differently according to their working period. In this study, the competencies required for new nurses were identified and the corresponding enabling competencies were identified. In the future, it is expected that a competency-based education program will be prepared based on these findings, and furthermore, it will be possible to provide high-quality medical and nursing services that meet patients' needs by improving the competency of new nurses and lowering the turnover rate.

• Nuclear Engineering and Technology
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• v.47 no.6
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• pp.700-711
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• 2015

Sodium-cooled fast breeder reactors use liquid sodium as a moderator and coolant to transfer heat from the reactor core. The main hazard associated with sodium is its rapid reaction with water. Sodium-water reaction (SWR) takes place when water or vapor leak into the sodium side through a crack on a heat-transfer tube in a steam generator. If the SWR continues for some time, the SWR will damage the surface of the defective area, causing it to enlarge. This self-enlargement of the crack is called "self-wastage phenomena." A stepwise numerical evaluation model of the self-wastage phenomena was devised using a computational code of multicomponent multiphase flow involving a sodium-water chemical reaction: sodiumwater reaction analysis physics of interdisciplinary multiphase flow (SERAPHIM). The temperature of gas mixture and the concentration of NaOH at the surface of the tube wall are obtained by a numerical calculation using SERAPHIM. Averaged thermophysical properties are used to assess the local wastage depth at the tube surface. By reflecting the wastage depth to the computational grid, the self-wastage phenomena are evaluated. A two-dimensional benchmark analysis of an SWAT (Sodium-Water reAction Test rig) experiment is carried out to evaluate the feasibility of the numerical model. Numerical results show that the geometry and scale of enlarged cracks show good agreement with the experimental result. Enlarged cracks appear to taper inward to a significantly smaller opening on the inside of the tube wall. The enlarged outer diameter of the crack is 4.72 mm, which shows good agreement with the experimental data (4.96 mm).

• Smart Structures and Systems
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• v.25 no.2
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• pp.241-254
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• 2020

Using confined shape memory alloy (SMA) bar or plate, this study proposes an innovative self-centering damper. The damper is essentially properly machined SMA core, i.e., bar or plate, that encased in buckling-restrained device. To prove the design concept, cyclic loading tests were carried out. According to the test results, the damper exhibited desired flag-shape hysteretic behaviors upon both tension and compression actions, although asymmetric behavior is noted. Based on the experimental data, the hysteretic parameters that interested by seismic applications, such as the strength, stiffness, equivalent damping ratio and recentering capacity, are quantified. Processed in the Matlab/Simulink environment, a preliminary evaluation of the seismic control effect for this damper was conducted. The proposed damper was placed at the first story of a multi-story frame and then the original and controlled structures were subjected to earthquake excitations. The numerical outcome indicated the damper is effective in controlling seismic deformation demands. Besides, a companion SMA damper which represents a popular type in previous studies is also introduced in the analysis to further reveal the seismic control characteristics of the newly proposed damper. In current case, it was found that although the current SMA damper shows asymmetric tension-compression behavior, it successfully contributes comparable seismic control effect as those having symmetrical cyclic behavior. Additionally, the proposed damper even shows better global performance in controlling acceleration demands. Thus, this paper reduces the concern of using SMA dampers with asymmetric cyclic behavior to a certain degree.

• Journal of Korean Academy of Nursing
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• v.36 no.8
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• pp.1308-1314
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• 2006

Purpose. The purposes of this study were to develop a PBL program for continuing nurse education and to evaluate the program after its implementation. Methods. The PBL program was developed in the core cardio-pulmonary nursing concepts through a collaborative approach with a nursing school and a hospital. The PBL packages with simulation on ACLS were implemented to 40 clinical nurses. The entire PBL program consisted of six 3-hour weekly classes and was evaluated by the participants' subjective responses. Results. Two PBL packages in cardio-pulmonary system including clinical cases and tutorial guidelines were developed. The 57.5 % of the participants responded positively about the use of PBL as continuing nurse education in terms of self-motivated and cooperative learning, whereas 20.0% of the participants answered that the PBL method was not suitable for clinical nurses. Some modifications were suggested in grouping participants and program contents for PBL. Conclusion. The PBL method could be utilized to promote nurses' clinical competencies as well as self-learning abilities. Further research is needed in the implementation strategies of PBL-based continuing education in order to improve its effectiveness.

• Steel and Composite Structures
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• v.46 no.5
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• pp.621-635
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• 2023

The combination of replaceable and repairable properties in structures has introduced new approach called "Low Damage Design Structures". These structural systems are designed in such a way that through self-centering, primary members and specific connections neither suffer damage nor experience permanent deformations after being exposed to severe earthquakes. The purpose of this study is the seismic assessment of steel moment resisting frames with the aid of rigid rocking cores. To this end, three steel moment resisting frames of 4-, 8-, and 12-story buildings with and without rocking cores were developed. The nonlinear static analysis and incremental dynamic analysis were performed by considering the effects of the vertical and horizontal components of 16 strong ground motions, including far-fault and near-fault arrays. The results reveal that rocking systems benefit from better seismic performance and energy dissipation compared to moment resisting frames and thus structures experience a lower level of damage under higher intensity measures. The analyses show that the interstory drift in structures equipped with stiff rocking cores is more uniform in static and dynamic analyses. A uniform interstory drift distribution leads to a uniform distribution of the bending moment and a reduction in the structure's total weight and future maintenance costs.

• Journal of Korean Academy of Nursing
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• v.17 no.1
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• pp.52-63
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• 1987

Il-primigravidas who visited antenatal clinic and their husbands were taught lamaze childbirth education by the investigator in the third trimester of pregnancy. Lamaze childbirth educational course consisted of six weekly class totaling twelve hours of instruction. A questionnaire was adminstered to subjects for the evaluation of Lamaze educational Program. 21-questions were rated on a Likert-type scale containing five responses and subjects described the advantages, the disadvantage, and the difficulties of lamaze childbirth education course. The results of the study were as follows; 1. The core contents of lamaze childbirth educational Program were Process of labor, anatomy and physiology of the female body, the care of newborn, maternal-infant attachment, breathing patterns to be used at the appropriate stage of labor, techniques for conscious relaxation of muscles during labor and delivery, and exercise to limber and prepare the body for the work of labor and delivery. All couples understood the above core contents very well and there were not significant differences between the understanding scores of wives and those of husbands (p>0.05). 2. 81.8% of couples Practiced breathing pattern to be used at the appropriate stages of labor one or three times a day and 72.7% of couples practiced conscious relaxation of muscles one or three times a day. 3. The contents of Lamaze childbirth educational program were easy for the couples to understand, and the total length, the amounts and the structures of 6-classes were appropriate. 4. Lamaze childbirth educational program was very useful, necessary, interesting, and successful to achieve the couples' objectives. 5. The couples expressed that they had positive attitude and high self-esteem, and reduced their anxiety on the pregnancy and labor.