• Proceedings of the Safety Management and Science Conference
• /
• 2009.04a
• /
• pp.105-108
• /
• 2009

기존의 연구논문들에서는 1975년부터 1992년 사이의 OECD 국가들에서 집권정부별 국민들이 느끼는 행복감을 알아보기 위한 분석들이 주로 이루어졌다. 이러한 행복감을 알아보는 데에는 특히 인플레이션율과 실업률이 주요 변수로 활용되고 있다. 각국별로 살펴볼 때, 진보정부의 경우에 있어서는 실업률에 더 주안점을 두는 반면에 보수정부는 인플레이션율에 더 민감하게 대처함을 알 수 있었다. 이러한 점들을 살펴보면, OECD 국가들에서 빈곤층은 진보정부를 선호하고 상대적으로 소득수준에서 상위계층은 보수정부를 선호할 것으로 추정된다. 이 논문에서는 한국의 경우 시계열 관계상 진 보정부와 보수정부로 나누지 않고 행복감에 대하여 소비자심리지수를 대용변수로 사 용하였을 경우 경기회복에 따른 산업생산 증가와 이를 위한 정부지출이 중요한 변수 임을 알 수 있었다.

• Journal of Service Research and Studies
• /
• v.6 no.3
• /
• pp.57-78
• /
• 2016

The purpose of this research is to study how service recovery activities influence customers' commodity churning in the media telecommunication industry(CATV industry). Put it differently, we tried to identify this change of commodity churning rates by the stages of service failures, by which we intend to emphasize the importance of service recoveries. Korean media telecommunication market has already been saturated; customers tend to move to bigger major companies with better customer care increasingly. As once customers gone never returns, CRM functions are being reinforced over the time. We were able to have the following results. First, turning rates, for those experienced service failure, who were dissatisfied with service recovery activities are 2~5 times (monthly average turning rates are 1.3%) higher than those satisfied. Secondly, active service recovery activities at the customer's service request after experiencing service failure lowered churning rates significantly. The most effective timing is service recovery activities pre-recovery stage. Thirdly, reward activities after service recovery activities at the immediate recovery stage is more effective than service recovery at the arranged recovery schedule and reward activities after customer's expressing churning intension. The implications of this study are that firms should engage in service recovery activities at the time of identifying service failures, prior to customer's expressing churning intention, which means relatively lower ROI for the service recovery activities than the times of customers' expressing churning intention.

• Composites Research
• /
• v.22 no.3
• /
• pp.29-34
• /
• 2009

In this paper, finite element analyses were used to estimate the strain distribution at the fracture site of a tibia bone. A stainless steel bone plate and various composite bone plates were considered to find out the best conditions for callus generation while bone fracture was cured for 16 weeks. Through this research, the appropriate load condition which makes the strains between the appropriate range($2{\sim}10%$) was sought. From this analysis, it was found that lower level of external load is needed for the appropriate strain for the case of composite bone plate application and it was also found that the composite bone plate had potential advantages for effective bone fracture healing relieved stress shielding effect.

• The Journal of Engineering Geology
• /
• v.23 no.2
• /
• pp.161-170
• /
• 2013

We analyzed the effect of changing water level and turbidity on plants that serve to maintain slope stability on levees. In this experiment, soil collected from upstream of Imha Dam was placed in a water tank and planted with river plants of the Salix species: Salix gracilistyla, S. koreensis, and S. glanduosa. Plant regrowth was analyzed stage-by-stage during a recovery period. In addition, we assessed the tolerance of the plants to concentrated torrential rainfall and examined their recovery rates. The results indicate that in the case of these three Salix species, which are the most prevalent river plants in Korea, stem growth is arrested following serious damage and high turbidity. The possibility of regrowth was very low during the 20-day non-submerged recovery period. Although the number of leaves initially decreased during this period, subsequent regrowth was reasonably high: recovery in S. gracilistyla, S. koreensis, and S. glanduosa was up to 59.3%, 251.3%, and 148.4% respectively, compared with the initial condition.

• Korean Journal of Environment and Ecology
• /
• v.29 no.5
• /
• pp.681-692
• /
• 2015

It is well documented that physiological and nutritional condition of wintering birds is strongly related to migration success to breeding sites, and also breeding success. However, how abiotic factors during winter affect the migration and breeding successes still remains unclear. Thus, this study developed a dynamic-state-dependent model for wintering life-history to identify the potential impact on the life-history, success to breeding site and breeding success of wintering birds, which are related to temperature fluctuation, interspecific competition and human disturbance at the wintering sites. To find the best-fit-model, we referred to the existing research data on wintering ecology of Red-crowned cranes (Grus japonensis) in Cheolwon, Korea, which is well documented as a long-term wintering study. Our model predicted that the higher temperature fluctuation and a higher rate of human disturbance are negatively related to migration success to breeding sites and their fitness, ultimately breeding success via changing of proportion in resource allocation (for e. g., lower energy compensation or higher level of stress accumulation). Particularly, the rate of body mass compensation after arrival at wintering sites may be accelerated when there are less temperature fluctuations and a lower rate of human disturbance. In addition, the rate of interspecific competition sharing the wintering foraging sites is negatively related to the rate of body mass compensation. Consequently, we discussed the conservation strategies of wintering birds based on the outcomes of the model.

• Journal of the Korean Geotechnical Society
• /
• v.29 no.2
• /
• pp.15-21
• /
• 2013

The analysis of long-term performance of pavement sections under wheel loads is normally conducted in two separated steps. First the resilient behavior of the pavement is calculated assuming the pavement is a layered or discrete elastic medium, and then the permanent deformation is evaluated based on empirical permanent displacement equations. Material properties required in both steps can be obtained from cyclic triaxial tests, in other words, resilient and permanent deformation tests. While this analytical approach is simple and convenient, it does not consider the modulus degradation caused by cyclic loads, and some types of reinforcements such as geosynthetic cannot be modeled in this type of analysis. A model for degraded secant modulus is proposed and suggested to be used for the analysis of permanent behavior of unpaved roadway sections. The parameter for suggested model can be obtained from cyclic triaxial tests, regular practice in pavement engineering. Examples to estimate the model parameters are presented based on both laboratory permanent deformation test and large-scale plate load test.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.14 no.5
• /
• pp.1231-1239
• /
• 2010

The aim of this study was developing the non-invasive focused magnetic stimulation system(NI_FMSS) that can stimulates acupoints which are small parts and knotted muscular tissues. To evaluate pain treatment effect of the NI_FMSS, we caused muscle fatigue to 25 subjects in biceps of the arm. Then, we stimulated acupoints(trigger points) HT2 using low frequency stimulator(10 subjects) and NI_FMSS(10 subjects). The other 5 subjects had not been stimulated. We analyzed muscle fatigue recovery with median frequency, RMS and median power in frequency domain for 5 days. We checked the magnetic stimulation effect on acupoint by evaluation of muscle fatigue recovery. Therefore, we identified that the NI_FMSS was more efficient system to relieve muscle pain than electric-stimulation system.

• Korean Journal of Ecology and Environment
• /
• v.46 no.2
• /
• pp.154-165
• /
• 2013

The species composition of the fish community was studied in four streams where fish kills have previously occurred in recent years; Worun Stream, Seo Stream, Jangnam Stream, and the Anyang Stream. The number of fish species varied from 22 to 86% compared to the number of fish species pre-fish kill. The recovery of fish populations in the streams seems to be determined by water quality and the presence of artificial structures in the streams. The Jangnam Stream, where alkaline pH caused a fish kill, showed a high recovery of fish species due to improvements in water quality. Anyang Stream had a low number of species, possibly because dissolved oxygen concentrations were intermittently low. Artificial structures in streams had a negative impact the recovery of fish species, particularly for benthic fish species. It appears that fish populations can recover rapidly when water quality improves or the movement of fish community is unimpeded. However, water quality and artificial structures in many streams in Korea still present adverse conditions for fish survival, deterring the recovery of fish populations. To conserve fish populations in streams, habitat all owing unimpeded movement for fish and controls on pollutant inputs are needed.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.12 no.3
• /
• pp.49-59
• /
• 2008

In this study, the design method of a 155 mm Solid Fuel Ramjet projectile is proposed and a flight performance analysis program through mathematical modelling is developed. Through flight performance analysis, ramjet performance during flight, which is comprised of thrust, specific impulse, pressure recovery ratio, location of shock waves, and magnitude of drag, was predicted. The results show that compared to Rocket Assisted Projectile(RAP), the range was increased by 90 %. Furthermore, how variations in nozzle exit area ratio and the intake area cause variations in range was observed. This research on modeling and simulation methodology will provide useful data for future development of solid fuel ramjet projectiles.

• Elastomers and Composites
• /
• v.40 no.4
• /
• pp.258-265
• /
• 2005

To study the compressive stress, recovery force and permanent strain of foams for footwear midsole, polyurethane(PU), phylon(PH) and injection phylon(IP) foams were repetitively compressed with constant compressive stress. Maximum compressive stress of PU did not decrease with repetitive compression on the constant compressive stress, but that of IP largely decreased. Engineering strain of foams were formed by repetitively compressing the three types of foam. The engineering strain of PU was smaller than that of IP and PH. Compressive stress and recovery force of IP and PH at certain strain were decreased with repetitive compression, but that of PU was not noticeably changed.