• Journal of Applied Reliability
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• v.18 no.3
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• pp.220-228
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• 2018

Purpose: The purpose of this study is to investigate the tail behavior of the life distribution which exhibits an increasing failure rate or other positive aging effects after a certain time point. Methods: We characterize the tail behavior of the life distribution with regard to certain reliability measures such as failure rate, mean residual life and reliability function and derive several stochastic properties regarding such life distributions. Also, utilizing an L-statistic and its asymptotic normality, we propose new nonparametric testing procedures which verify if the life distribution has an increasing tail failure rate. Results: We propose the IFR-Tail (Increasing Failure Rate in Tail), DMRL-Tail (Decreasing Mean Residual Life in Tail) and NBU-Tail (New Better than Used in Tail) classes, all of which represent the tail behavior of the life distribution. And we discuss some stochastic properties of these proposed classes. Also, we develop a new nonparametric test procedure for detecting the IFR-Tail class and discuss its relative efficiency to explore the power of the test. Conclusion: The results of our research could be utilized in the study of wide range of applications including the maintenance and warranty policy of the second-hand system.

• Management & Information Systems Review
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• v.33 no.3
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• pp.167-187
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• 2014

While Korean GAAP had detailed regulations for the measurement and disclosure of operating income in the past, K-IFRS did not provide specific rules for operating income until 2011. Some firms that adopted K-IFRS before 2011 did not disclose or calculated operating income in an inconsistent manner although operating income is usually considered as one of the core information items to assess firm valuation. Inconsistency in firms' treatment of operating income invoked much criticism from diverse users of financial statement. The Korean Accounting Institute (KAI hereafter) revised the K-IFRS rules relevant to operating income in September 2010 in response to the voices raised by the business community, whereby the operating income number is allowed to be calculated in conformity with the previous K-GAAP. This study was motivated by the revision of K-IFRS and aims to provide a clue on the validity of such policy decision. To achieve the research objective, we test the relative value relevance of the alternative operating income numbers under K-IFRS versus K-GAAP. Our main findings are as follows. The value relevance of operating income reported before K-IFRS is proved to be higher than after K-IFRS. K-IFRS operating income adjusted to the previous K-GAAP has greater explanatory power for market values relative to one calculated under the K-IFRS regime. In an additional analysis, the sample was decomposed according to whether the operating income under K-IFRS is greater than under K-GAAP. The difference in the value relevance of K-IFRS versus K-GAAP operating income is significant only in the subsample consisting of firms which reports higher operating income under K-IFRS compared to K-GAAP. Also, the firms which would have reported negative operating income on a consecutive basis are more likely to have chosen K-IFRS, resulting in higher numbers than otherwise. It is likely that firms facing the threat of delisting due to consecutive operating loss reporting are more likely to have adopted K-IFRS disclosure rules by which they could report higher operating income numbers. To sum up, these results corroborate the limitation inherent in the K-IFRS regarding operating income disclosures. This paper suggests that the recent revision of K-IFRS implemented by KAI is likely to mitigate some of afore-mentioned limitations effectively.

• Journal of Nutrition and Health
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• v.48 no.2
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• pp.149-156
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• 2015

Purpose: This study examined the effects of combined intervention of isoflavones and exercise on bone mineral density, bone mineral content, and biochemical bone markers. Methods: Forty rats were divided into four groups; Control, Isoflavones (IF), Isoflavones + Running (IFR), and Isoflavones + Swimming (IFS). All of the rats in this study were fed an experimental diet and deionized water ad libitum for nine weeks. Bone mineral density (BMD) and bone mineral content (BMC) were estimated using PIXImus (GE Lunar Co, Wisconsin.) in spine and femur nine weeks after feeding or training. Results: The combined intervention did not affect weight gain, mean food intake, or food efficiency ratio. The serum concentrations of ALP and osteocalcin were not significantly different by combined intervention. The urinary DPD crosslinks values were not significantly different by combined intervention. There were no significant differences in serum PTH, calcitonin, and estradiol among all groups. Spine BMD, spine BMC and femur BMC were not significantly different by combined intervention. However, femur BMD was significantly higher in the IFR group than in the control group. Compared with the control group, spine BMD, spine BMC, and femur BMD per weight were markedly increased in the isoflavones supplementation and combined intervention group. In addition, femur BMC per weight was significantly higher in the IFS group than in the control group. Compared with the isoflavones supplemented group, BMD and BMC were not significantly different by combined intervention. Conclusion: It can be concluded that isoflavones supplementation or combined intervention of isoflavone and exercise had a beneficial effect on spine and femur peak bone mass in growing female rats.

• Journal of the Korean Geotechnical Society
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• v.30 no.12
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• pp.51-61
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• 2014

This paper presents an experimental study of the plugging effect on the capacity of open-ended piles installed in sandy soil. Full-scale tests, including dynamic and static axial-compression load tests, were carried out on three instrumented piles with different diameters (508.0, 711.2 and 914.4 mm). To measure the outer and inner shaft resistances acting on the piles, a double-walled system was utilized with instrumented strain gauges on the outside and inside walls of the pile. The results of field tests show that the inner shaft resistance was mostly mobilized at the location between the pile tip and 18-34% of the total plug length. It was found that the soil plugging in the lower portion has influence on the inner shaft resistance. In addition, it can be also demonstrated that the ratio of inner shaft resistance plus annulus load resistance to total resistance decreased with increasing pile diameters. The results of these tests show that the relationship between the degree of plugging and pile diameter is clearly established. Direct observations of the soil plugs were made and used to quantify both the plug length ratio (PLR) and the incremental filling ratio (IFR). Based on this result, it was found that the N value of the standard penetration test (SPT) is highly correlated with the IFR.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.8
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• pp.1883-1892
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• 2015

TRIZ is a theory of inventive problem solving. Recently the importance of creative capabilities is being emphasized and many successful cases using TRIZ are being introduced, therefore interest in TRIZ has been increasing. But TRIZ is not easy to learn alone compared to other creative thinking tools. Although it is effective to learn TRIZ through various cases, it is not easy for beginners to experience those many cases. Therefore, we developed a software called Do-TRIZ for TRIZ learning. Do-TRIZ provides descriptions and various examples of key concepts to make it easier for beginners to learn TRIZ. Also, the learners can add new cases continuously on Do-TRIZ. Especially, process-based problem solving modules have been implemented on Do-TRIZ, in order to make it possible to solve problems based on technical contradiction, physical contradiction, and IFR(Ideal Final Result). The learners can use the modules to solve their problems and to share the results. Also, we implemented Do-TRIZ Memo app that works with Do-TRIZ.

• The Journal of Advanced Prosthodontics
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• v.13 no.6
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• pp.385-395
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• 2021

PURPOSE. To characterize the microstructure of three yttria partially stabilized zirconia ceramics and to compare their hardness, indentation fracture resistance (IFR), biaxial flexural strength (BFS), and fatigue flexural strength. MATERIALS AND METHODS. Disc-shaped specimens were obtained from 3Y-TZP (Vita YZ HT), 4Y-PSZ (Vita YZ ST) and 5Y-PSZ (Vita YZ XT), following the ISO 6872/2015 guidelines for BFS testing (final dimensions of 12 mm in diameter, 0.7 and 1.2 ± 0.1 mm in thicknesses). Energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses were performed, and mechanical properties were assessed by Vickers hardness, IFR, quasi-static BFS and fatigue tests. RESULTS. All ceramics showed similar chemical compositions, but mainly differed in the amount of yttria, which was higher as the amount of cubic phase in the diffractogram (5Y-PSZ > 4Y-PSZ > 3Y-TZP). The 4Y- and 5Y-PSZ specimens showed surface defects under SEM, while 3Y-TZP exhibited greater grain uniformity on the surface. 5Y-PSZ and 3Y-TZP presented the highest hardness values, while 3Y-TZP was higher than 4Y- and 5Y-PSZ with regard to the IFR. The 5Y-PSZ specimen (0.7 and 1.2 mm) showed the worst mechanical performance (fatigue BFS and cycles until failure), while 3Y-TZP and 4Y-PSZ presented statistically similar values, higher than 5Y-PSZ for both thicknesses (0.7 and 1.2 mm). Moreover, 3Y-TZP showed the highest (1.2 mm group) and the lowest (0.7 mm group) degradation percentage, and 5Y-PSZ had higher strength degradation than 4Y-PSZ group. CONCLUSION. Despite the microstructural differences, 4Y-PSZ and 3Y-TZP had similar fatigue behavior regardless of thickness. 5Y-PSZ had the lowest mechanical performance.

• The Journal of Korean Institute for Practical Engineering Education
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• v.1 no.1
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• pp.1-6
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• 2009

Traditionally engineers' main roles are concentrated on solving any given problems and engineering education has emphasized problem solving ability. Therefore engineers intend to solve easily perceived problems with their knowledge and experience instead of trying to analyze the given problems thoroughly and to define real problems, and go through lots of trial and error. So, engineers require the ability to define real problems accurately before trying to solve the problems. This study proposes a real problem definition process using visualization of a core zone and TRIZ concepts such as contradictions and IFR(Ideal Final Result) in order to define real problems with minimum trial and error. TRIZ is the theory of inventive problem solving and was developed by a Soviet engineer and researcher Genrich Altshuller from 1946. Nowadays many industries use TRIZ and its effectiveness was already proved by lots of real problem solving in various areas. Therefore TRIZ might be very effective tool for developing students' inventive thinking ability in engineering education.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.9
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• pp.1257-1261
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• 2006

Pleiomorphic adenoma gene-like1 (PLAGL1) encodes a zinc-finger (ZF) protein with seven ZFs of the C2H2-type which is a regulator of apoptosis and cell cycle arrest, and also regulates the secretion of insulin. In both human and mouse, PLAGL1 is a candidate gene for tumor suppressor and transient neonatal diabetes mellitus (TNDM). In this study, a 2,238 bp fragment covering the complete coding region was obtained and deposited to GenBank (accession number: DQ288899). The reverse transcriptase-polymerase chain reaction (RT-PCR) indicated that PLAGL1 was expressed almost equally in heart, liver, spleen, lung, kidney, stomach, small intestine, skeletal muscle, fat, uterus and ovary. Comparing the sequences of Large White and Meishan pigs, a C-T transition in exon 6 was found. The polymorphism could be detected by TaqI and was genotyped in five purebreds (Large White, Landrace, Meishan, Tongcheng and Bamei). Association analysis was performed between the polymorphism and carcass traits in 276 pigs of a "Large White${\times}$Meishan" F2 resource population. As a consequence, significant associations of the genotypes with shoulder backfat thickness (SFT) and internal fat rate (IFR) were observed. Pigs with TT genotype had low SFT and high IFR compared with TC or CC genotypes.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.1
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• pp.89-93
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• 2020

In this paper, Ku-band Receiver for compact doppler radar has been designed and fabricated. It composed of MWR(Microwave Receiver) and IFR(Intermediate Frequency Receiver) which have 5 receive path. We applied limiter circuit to protect MWR from Tx leakage power and maximum 2 W. IFR can change the Rx path to broad band or narrow band by MSC(Mode Selection Switch). It is observed that fabricated receiver performs 68 dB gain and 3.7 dB noise figure, 93 ns limiter recovery time. Proposed Ku-band receiver is expected to apply for Ku-band compact doppler radar.

• Journal of Korean Society of Transportation
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• v.23 no.6 s.84
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• pp.55-67
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• 2005

There are 24 airways in Incehon IFR, including 11 domestic routes and 13 international routes. The airways designated by ministry of Transportation and Construction are the routes for aircraft to fly being serviced by air traffic control system for flight safety. This study reviewed safety situation of existing permanent airways within Incheon IFR and temporary airways connecting North and South Korea. The study tried to identify the problems related to airway operation and to suggest solutions to the questionable area. The main findings are as follows: It is necessary to improve the existing normal airway systems and enlargement of the route. The airway A593 has to be upgraded to normal route. The temporary airways established to connect Seoul and Pyongyang also needs to be upgraded by air traffic control transfer agreement between two Koreas.