• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.12 no.6
• /
• pp.112-122
• /
• 2009

Payment of Forest Landscape Service (PFLS) is based on the value of landscape conservation and is a positive forest policy inducing the owners of mountains to improve environmental service quality with economic incentives. The purpose of this study is to test the feasibility of PFLS and find out the elements related to PFLS such as associated statutes, target applications, eligible owner's requirements, and applicable environmental services. Research sites were selected in designated reserved forests by law and surveys were carried out with 28 professional forestry engineers and 10 owners of reserved forests located in Chungnam Province in November, 2008. As a result, the owners are willing to participate pilot-project of PFLS if they could have tax incentives. Preferred activities in their forestry are eco-tourism and carbon emission trading as PFLS business model. Although they expect low economic benefit from the PFLS, respondents answered introducing PFLS will give good opportunities for owners of a reserved forest to enhance willingness to manage their forestry properly for the landscape conservation. In this study, PFLS evaluation indicators and policy directions are established and recommends the strategies to cope with changing needs of forestry conservation by inducing the owners' active participation in the sustainable forest landscape management.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.19 no.6
• /
• pp.30-36
• /
• 2011

The current test methods are insufficient to evaluate and ensure the safety and reliability of vehicle system for all possible dynamic situation including the worst case such as rollover, spin-out and so on. Although the known NHTSA Sine with dwell steering maneuvers are applied for the vehicle performance assessment, they aren't enough to estimate other possible worst case scenarios. Therefore, it is crucial for us to verify the various worst cases including the existing severe steering maneuvers. This paper includes useful worst case based upon the existing worst case scenarios mentioned above and worst case evaluation for vehicle dynamic controller in simulation basis and UCC HILS. The only human steering angle is selected as a design parameter here and optimized to maximize the index function to be expressed in terms of both yaw rate and side slip angle. The obtained scenarios were enough to generate the worst case to meet NHTSA worst case definition. It has been concluded that the new procedure in this paper is adequate to create other feasible worst case scenarios for a vehicle dynamic control system.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.20 no.5
• /
• pp.26-34
• /
• 2016

The failure modes of steel column-base plate connection arranged on the basis of AISC Design Guide-#1 and -#10 are base plate tension and compression side flexural yielding, yielding, pull-out and shear failure of anchor rod, concrete crushing in concrete footing and steel column yielding. The bending moment capacity and failure mode in this connection are predicted using limit-state function and we compare these results and test result. In the case that thickness of base plate is relatively thick, bending moment capacity and failure mode in steel column-base plate connection accurately predicted. But in the case that thickness of base plate is relatively thin and axial force do not exist, prediction of failure mode in this connection is somewhat inaccurate.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.22 no.1
• /
• pp.13-22
• /
• 2018

In this study, seismic performance of existing RC frames reinforced with steel chevron bracing systems was experimentally evaluated. For this purpose, the unreinforced base specimen and seismically reinforced specimens with steel chevron bracing systems were fabricated and tested. Both strength and stiffness of the reinforced specimens were targeted about 2-3 times larger than the base specimen. Test results showed that the stiffness, strength, and ductility of the reinforced specimens considerably improved than those of unreinforced base specimen. Therefore, the results from this study could offer the basic information on the developing design guideline for the seismic reinforcement of RC frames.

• The Journal of Korean Academic Society of Nursing Education
• /
• v.17 no.1
• /
• pp.14-24
• /
• 2011

Purpose: The purpose of this study was to investigate the learning effect of a standardized patient managed instruction program for a clinical maternity nursing course. Methods: The SP managed instruction was made for clinical cases in intrapartum and postpartum nursing care. The SP managed instruction was evaluated by using a quasi-experimental, nonequivalent control group post-test design with separate classes of students attending clinical maternity nursing classes at a nursing school in Incheon. Control groups were taught by traditional lecture/model method and experimental groups were taught by SP managed instruction. Data was collected from September 2009 to February 2010. Results: 1. There was no significant difference between the experimental group and control group in identifying relevant data (z=-1.418, p=.156) and necessary nursing skills performance (z=-.643, p=.520) for intrapartum nursing care. In addition, there was no significant difference between the two groups in identifying relevant data (z=-.264, p=.782) and necessary nursing skill (z=-.342, p=.732) for postpartum nursing care. 2. In clinical nursing skill performances the total score was statistically significantly higher in the experimental group than the control group (intrapartum care z=-4.181, p=.000, postpartum care z=-4.279, p=.000). 3. There was a statistically significant difference between the two groups (intrapartum care z=-3.731, p=.000, postpartum care z=-4.066, p=.000). Conclusion: In conclusion, the SP methodis effective in teaching clinical maternity nursing for student nurses and it is necessary to develop SP instruction courses for many areas in the clinical nursing education field.

• Journal of Technologic Dentistry
• /
• v.39 no.3
• /
• pp.137-143
• /
• 2017

Purpose: The purpose of this study is to analyze the fitness of heat - pressed ceramic laminate veneers fabricated using the additive manufacturing. Methods: Impression was replicated by using light body silicone and heavy body silicone on the custom tray, and it was fabricated using Type IV Stone. The test specimens were prepared by using a dental scanner, a laminating veneer using a dental design program, and a specimen with a 3D printer. The control specimens were prepared by the lost wax technique and heat - pressed to fabricate the specimens. The data of the specimens were measured by the RMS value of the internal fitness a using a 3-dimensional measurement program. Results: The Stereolithography laminate veneer group was measured at $78.10(4.09){\mu}m$ and the LWV group was measured at $31.50(5.10){\mu}m$. There is a significant difference between the two groups (p<0.001) Conclusion : Evaluation of fitness laminate veneers was fabricated by additive manufacturing showed the difference statistically significantly and clinically acceptable result.

• Journal of the Society of Naval Architects of Korea
• /
• v.48 no.2
• /
• pp.147-157
• /
• 2011

A RANS(Reynolds averaged Navier-Stokes) based numerical method is developed for the evaluation of ship resistance and self-propulsion performances. In the usability aspect of CFD for the hull form design, the field grid around practical hull forms is generated by solving a grid Poisson equation based on the hull surface grid generated from station offsets and centerline profile. A body force technique is introduced to model the effects of the propeller in which the propeller loads are obtained from potential flow analysis using an unsteady lifting surface method. The free surface is captured by using a two-phase level-set method and the realizable $k-{\varepsilon}$ model is used for turbulence closure. The hull attitude in vertical plane, i.e., trim and sinkage, is calculated by using a quasi-steady method and then considered in the computation by translating and rotating the grid system according to the values. For the validation of the proposed method, the numerical results of resistance tests for KCS, KLNG, and KVLCC1 and of self-propulsion test for KCS are compared with experimental data.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.8 no.3
• /
• pp.423-436
• /
• 1996

Thermodynamic performance of eight zeotropic R-22 alternative refrigerant mixtures selected by AREP(R-22 Alternative Refrigerants Evaluation Program) and R-32/R-125/R-134a(23%/25%/52%), namely R-407C were evaluated by the "drop-in" simulation method. An existing air conditioner was selected and its design data were used for the simulation. "ARI Test A" air conditions were applied. The degree of vapor superheat at the compressor inlet fixed at $5^{\circ}C$ for all the mixtures. The results of the simulation were compared with those of R-22. COPs of all mixtures except for R-32/R-227ea(35%/65%) and R-32/R-125/R-134a(10%/70%/20%), were higher than that of R-22 by 2%~8%, while the capacities were all lower than that of R-22 by 13%~27%. COP of R-32/R-134a(40%/60%) was 2.4% higher but the capacity was 15% lower than those of R-22. In the case of R-32/R-134a(30%/70%), COP and capacity were 5.5% higher and 15% lower than those of R-22, respectively. Among the ternary mixtures, R-407C and R-32/R-125/R-134a(30%/10%/60%) showed the best performance. COP of R-407C was 2.4% higher than those of R-22 but the capacity was 15% lower.

• Journal of the Korean Society for Railway
• /
• v.13 no.6
• /
• pp.552-558
• /
• 2010

Ride comfort of railway vehicles is affected by many factors, such as vibration, noise, smell, temperature, visual stimuli, humidity and a seat design. In general, vibration, which originates from vehicle motion, is considered as the primary concern. In evaluating the ride comfort, relationship between passenger's feeling and vibration characteristics is very important because human feeling is dependent on frequency spectrum of vibration. Therefore, the weighing functions in frequency domain are used to evaluate the ride comfort of railway vehicles. In the present paper, we have analyzed the characteristics of the frequency weighting curves defined in many standards and reviewed the effect resulting from their difference on the ride comfort.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.34 no.11
• /
• pp.1705-1713
• /
• 2010

The reliable fatigue life for hybrid composite joint structures was estimated by a statistical method for evaluating fatigue life; the results of the fatigue test varied widely. Cyclic bending tests were performed on a cantilever beam with a hybrid composite joint, which was developed for the body of a low-floor bus. In order to estimate the fatigue life of the hybrid composite joint structure by comparing the data obtained during the fatigue tests, the most suitable probabilistic density function among the normal, lognormal, and Weibull distributions was selected. The probabilistic-stress-life (P-S-N) curves calculated by using the selected Weibull distribution was suggested for process of statistical fatigue life estimation and reliability design.