• The Transactions of the Korean Institute of Electrical Engineers D
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• v.51 no.4
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• pp.144-151
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• 2002

This paper presents a fault-tolerant duplex architecture to build a high-reliability microcontroller using commercial VLSI processors. The architecture supports fail-silence under all single-failure situations and facilitates recovery from transient failures. The paper implements the duplex architecture using two Motorola MC68360 processors and evaluates its fault tolerance in a real application environment.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.4
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• pp.150-159
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• 2018

The present research deals with a finite element analysis and fatigue evaluation of a steam separator of a high-pressure evaporator for the Heat Recovery Steam Generator (HRSG). The fatigue during the expected life of the HRSG was evaluated according to the ASME Boiler and Pressure Vessel Code Section VIII Division 2 (ASME Code). First, based on the eight transient operating conditions prescribed for the HRSG, temperature distribution of the steam separator was analyzed by a transient thermal analysis. Results of the thermal analysis were used as a thermal load for the structural analysis and used to determine the mean cycle temperature. Next, a structural analysis for the transient conditions was carried out with the thermal load, steam pressure, and nozzle load. The maximum stress location was found to be the riser nozzle bore, and hence fatigue was evaluated at that location, as per ASME Code. As a result, the cumulative usage factor was calculated as 0.00072 (much less than 1). In conclusion, the steam separator was found to be safe from fatigue failure during the expected life.

• Geomechanics and Engineering
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• v.4 no.2
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• pp.121-134
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• 2012

The paper presents the results of identification, monotonous and cyclic triaxial tests on a potentially liquefiable soil from the Guadeloupe island. The material is a very soft clayey soil whose susceptibility to liquefaction is not clear when referring to index properties such as grain size distribution, plasticity, etc. The classifications found in the literature indicate that the material has rather a "clay-like" behaviour, i.e., is not very susceptible to liquefaction, but its properties are very close to the threshold values given by the authors. Cyclic triaxial tests carried out on the material under different conditions show that liquefaction is possible for a relatively important level of cyclic deviator or number of cycles. The second part of the paper is devoted to the study of the recovery of the soil after liquefaction and possibly reconsolidation. For the specimens tested without reconsolidation, that simulated the soil immediately after an earthquake, the recovery is nearly non-existent but the drop in pore pressure during extension results in a small available strength. On the contrary, after reconsolidation, the increase in strength of the liquefied specimens is quite large, compared to the initial state, but with unchanged failure envelopes.

• Journal of Chest Surgery
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• v.13 no.3
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• pp.237-242
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• 1980

This is a case report of spontaneous regression of elevated pulmonary vascular resistance after the age of 6 years in a patient with partial endocardial cushion defect. The patient was first evaluated and considered to be highly risky for surgical correction because of obstructive type of pulmonary hypertension and presisting congestive heart failure at the age of 6 years, during which time medical treatment for congestive heart failure and sufferring from respiratory infection were only provided. Finally the patient was reevaluated at the age of 16 years, in January of 1980 when cardiac catheterization was revealed markedly reduced pulmonary vascular resistance and pulmonary hypertension as well. The patient was operated upon with uneventful postoperative recovery. So we report this case with review of the literatures regarding natural history regarding natural history of partial endocardial cushion defect.

• Journal of Platform Technology
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• v.11 no.6
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• pp.3-12
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• 2023

In today's system operation, it is difficult to detect failures and take immediate action in the case of a shortage of manpower compared to the number of equipment or failures in vulnerable time zones, which can lead to delays in failure recovery. In addition, various algorithms exist to detect abnormal symptom data, and it is important to select an appropriate algorithm for each problem. In this paper, an ensemble-based isolation forest model was used to efficiently detect multivariate point anomalies that deviated from the mean distribution in the data set generated to predict system failure and minimize service interruption. And since significant changes in memory space usage are observed together with changes in CPU usage, the problem is solved by using LSTM-Auto Encoder for a collective anomaly in which another feature exhibits an abnormal pattern according to a change in one by comparing two or more features. did In addition, evaluation indicators are set for the performance evaluation of the model presented in this study, and then AI model evaluation is performed.

• KDI Journal of Economic Policy
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• v.30 no.1
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• pp.171-209
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• 2008

The Great Depression is one of the most important economic incidents in the twentieth century. A significant and long-lasting impact of this event is the rise of the government intervention to the economy. Under the catastrophic downturn of the economic condition worldwide, people required their government to play an active role for economic recovery, and this $mentalit{\acute{e}}$ prolonged even after the Second World War. Social science textbooks taught at Korean high schools mostly referred to the Great Depression for explaining the reason of government intervention in economy. However, the mainstream view commonly found in the textbooks provides a misleading theological interpretation. It argues that inherent flaws of the market economy causes over-production/under-consumption, and that this mismatch ends up with economic crisis. The chaotic situation was resolved by substitution of the governments for the market, and the New Deal was introduced as the monumental example ('laissez-faire economy ${\rightarrow}$over-production${\rightarrow}$the Great Depression${\rightarrow}$government intervention${\rightarrow}$economic recovery'). Based on economic historians' researches for past three decades, I argue that this mainstream view commits the fallacy of ex-post justification. Unlike what the mainstream view claims, the Great Depression was neither the result of the 'market failure', nor the recovery from the Great Depression but was due to successful government policies. For substantiating this claim, I suggest three points. First, blaming the weakness or instability of the market economy as the cause of the Great Depression is groundless. Unlike what the textbooks describe, the rise of the U.S. stock price during the 1920s cannot be said as a bubble, and there was no sign of under-consumption during the 1920s. On the contrary, a new consensus emerging from the 1980s among economic historians illustrates that the Great Depression was originated from 'the government failure' rather than from the 'market failure'. Policymakers of European countries tried to return to the gold standard regime before the First World War, but discrepancies between this policy and the reality made the world economy vulnerable. Second, the mainstream view identifies the New Deal as Keynesian interventionism and glorifies it for saving the U.S. economy from the crisis. However, this argument is not true. The New Deal was not Keynesian at all. What the U.S. government actually tried was not macroeconomic stabilization but price and quantity control. In addition, New Deal did not brought about economic recovery that people generally believe. Even after the New Deal, industrial production or employment level remained quite low until the late 1930s. Lastly, studies on individual New Deal policies show that they did not work as they were intended. For example, the National Industrial Recovery Act increased unemployment, and the Agricultural Adjustment Act expelled tenants from their land. Third, the mainstream view characterizes the economic order before the Great Depression as laissez-faire, and it tends to attribute all the vice during the Industrial Revolution era to the uncontrolled market economy. However, historical studies show that various economic and social problems of the Industrial Revolution period such as inequality problems, child labor, or environmental problems cannot be simply ascribed to the problems of the market economy. In conclusion, the remedy for all these problems in high school textbooks is not to use the Great Depression as an example showing the weakness of the market economy. The Great Depression should be introduced simply as a historical momentum that had initiated the growth of government intervention. This reform of high school textbooks is imperative for enhancing the right understanding of economy and history.

• Nutrition Research and Practice
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• v.16 no.3
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• pp.314-329
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• 2022

BACKGROUND/OBJECTIVES: Oocyte lipid droplets play a crucial role in meiosis and embryo development. Biotin is associated with fatty acid synthesis and is the coenzyme for acetyl-CoA carboxylase (ACC). The effects of a biotin deficiency on the oocyte lipid metabolism remain unknown. This study examined the effects of a biotin deficiency and its replenishment on murine 1) oocyte lipid droplet levels, 2) ovary lipid metabolism, and 3) oocyte meiosis. MATERIALS/METHODS: Mice were divided into 3 groups: control, biotin deficient (BD), and recovery groups. The control and BD groups were fed a control diet or BD diet (0.004 or 0 g biotin/kg), respectively. The recovery group mice were fed a BD diet until day 21, and were then fed the control diet from days 22 to 64. This study then quantified the oocyte lipid droplet levels, assessed the oocyte mitochondrial function, and examined the ability of oocytes to undergo meiosis. Ovarian phosphorylated ACC (p-ACC), lipogenesis, β-oxidation, and ATP production-related genes were evaluated. RESULTS: The BD group showed a decrease in lipid droplets and mitochondrial membrane potential and increased p-ACC levels. In the recovery group, the hepatic biotin concentration, ovarian p-ACC levels, and mitochondrial membrane potential were restored to the control group levels. On the other hand, the quantity of lipid droplets in the recovery group was not restored to the control levels. Furthermore, the percentage of oocytes with meiotic abnormalities was higher in the recovery group than in the control group. CONCLUSIONS: A biotin deficiency reduced the oocyte lipid droplet levels by downregulating lipogenesis. The decreased lipid droplets and increased oocyte meiosis failure were not fully restored, even though the biotin nutrition status and gene expression of lipid metabolism was resumed. These results suggest that a biotin deficiency remains robust and can be long-lasting. Biotin might play a crucial role in maintaining the oocyte quality.

• Journal of the Ergonomics Society of Korea
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• v.14 no.1
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• pp.9-23
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• 1995

The objectives of the study were twofole: (1) to investigate effects of rhythmic contraction and sustained contraction methods on recovery rate of isometric endurance capacity and (2) to compare aptterns of muscle recruitment of both arms observed during each contraction period. In the experiment, each of two subjects performed five successive rhythmic or sustained isometric contractions at 50% MVC with both arms to the point of fatigue, which was the failure to maintain the required tension. In making the contractions, the subjects stood erect with upper arms held at an angle of approximately 90 .deg. to the forearm. The interval between the successive contractions was kept constant at 3, 7, 20, or 40 minutes. Regardless of the contraction methods, the recovery rate was least at the shortest interval and was highest at the longest interval. However, a statistical analysis showed that the recovery rates for the rhythmic contractions were significantly lower than those for the sustained contractions throughout 4 different intervals. Furthermore, as the frequency of the rhythmic contractions per min, increased 4 to 6 times, the recovery rate of isometric endurance capacity decreased. From an EMG anglysis, recruitment pattern of the muscules of both arms was found to be common between two different contraction methods. The biceps muxcles of the upper arms played a major role in exerting 50% MVC, while the brachioradialis muscles of the forearms acted as synergists. As the contraction proceeded, the role of the biceps muscles as a prime mover lessened due to the fatigue. Then, the brachioradialis muscles exerted more strength to sustain 50% MVC. The implications of these finding were discussed.

• Management & Information Systems Review
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• v.33 no.1
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• pp.17-43
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• 2014

research tries to present the role of perceived justice and authenticity in service recovery process. Prior research on the service recovery have focused on relationship among perceived justice, recovery satisfaction and positive customer behavior. Especially perceived justice including distributive, procedural, and interactional justice has addressed as most important antecedents of recovery satisfaction. Although the pivotal role of perceived justice for successful service recovery has agreed by many researchers, relatively little attention has been paid to emotional aspect of customer. During the service recovery process, even if customer perceived recovery effort from service provider as justice one, they might feel displeasure or dissatisfaction. It means prior researches have underestimated the importance of emotional aspect while they focus on cognitive aspects. The one research focused on emotional aspects examined effect of authenticity in service context with other related factors. However, solely examined effect of authenticity is not enough to present proper implication effect between justice and authenticity so that it can be understood more clearly. In this study, we examined customer reactions to service failure and recovery process in restaurant service settings. Specifically, we focused on the moderating effect of authenticity on the paths between perceived justice and outcome variables such as forgiveness and recovery satisfaction.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.10
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• pp.29-39
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• 2008

Greedy routing which is easy to apply to geographic wireless sensor networks is frequently used. Greedy routing works well in dense networks whereas in sparse networks it may fail. When greedy routing fails, it needs a recovery algorithm to get out of the communication void. However, additional recovery algorithm causes problems that increase both the amount of packet transmission and energy consumption. Communication void is a condition where all neighbor nodes are further away from the destination than the node currently holding a packet and it therefore cannot forward a packet using greedy forwarding. Therefore we propose a VODUA(Virtually Ordered Distance Upgrade Algorithm) as a novel idea to improve and solve the problem of void. In VODUA, nodes exchange routing graphs that indicate information of connection among the nodes and if there exist a stuck node that cannot forward packets, it is terminated using Distance Cost(DC). In this study, we indicate that packets reach successfully their destination while avoiding void through upgrading of DC. We designed the VODUA algorithm to find valid routes through faster delivery and less energy consumption without requirement for an additional recovery algorithm. Moreover, by using VODUA, a network can be adapted rapidly to node's failure or topological change. This is because the algorithm utilizes information of single hop instead of topological information of entire network. Simulation results show that VODUA can deliver packets from source node to destination with shorter time and less hops than other pre-existing algorithms like GPSR and DUA.