• Atmosphere
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• v.23 no.4
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• pp.471-483
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• 2013

Nighttime sea fog detection from satellite is very hard due to limitation in using visible channels. Currently, most widely used method for the detection is the Dual Channel Difference (DCD) method based on Brightness Temperature Difference between 3.7 and 11 ${\mu}m$ channel (BTD). However, this method have difficulty in distinguishing between fog and low cloud, and sometimes misjudges middle/high cloud as well as clear scene as fog. Using CALIPSO Lidar Profile measurements, we have analyzed the intrinsic problems in detecting nighttime sea fog from various satellite remote sensing algorithms and suggested the direction for the improvement of the algorithm. From the comparison with CALIPSO measurements for May-July in 2011, the DCD method excessively overestimates foggy pixels (2542 pixels). Among them, only 524 pixel are real foggy pixels, but 331 pixels and 1687 pixels are clear and other type of clouds, respectively. The 514 of real foggy pixels accounts for 70% of 749 foggy pixels identified by CALIPSO. Our proposed new algorithm detects foggy pixels by comparing the difference between cloud top temperature and underneath sea surface temperature from assimilated data along with the DCD method. We have used two types of cloud top temperature, which obtained from 11 ${\mu}m$ brightness temperature (B_S1) and operational COMS algorithm (B_S2). The detected foggy 1794 pixels from B_S1 and 1490 pixel from B_S2 are significantly reduced the overestimation detected by the DCD method. However, 477 and 446 pixels have been found to be real foggy pixels, 329 and 264 pixels be clear, and 989 and 780 pixels be other type of clouds, detected by B_S1 and B_S2 respectively. The analysis of the operational COMS fog detection algorithm reveals that the cloud screening process was strictly enforced, which resulted in underestimation of foggy pixel. The 538 of total detected foggy pixels obtain only 187 of real foggy pixels, but 61 of clear pixels and 290 of other type clouds. Our analysis suggests that there is no winner for nighttime sea fog detection algorithms, but loser because real foggy pixels are less than 30% among the foggy pixels declared by all algorithms. This overwhelming evidence reveals that current nighttime sea fog algorithms have provided a lot of misjudged information, which are mostly originated from difficulty in distinguishing between clear and cloudy scene as well as fog and other type clouds. Therefore, in-depth researches are urgently required to reduce the enormous error in nighttime sea fog detection from satellite.

• Journal of Labour Economics
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• v.38 no.4
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• pp.1-29
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• 2015

The Individual Retirement Pension (IRP) enables workers to continuously receive a retirement pension even when workers change their jobs in different companies and so it performs a bridge fund as the complimentary living expenses until they receive government public pension. Although the Korean government has forced workers to maintain an IRP account until their retirement age and to close their accounts only when they want to do so, it is not clear to measure its really effectiveness and, in fact, most of IRP accounts have been terminated immediately after the changes of their jobs. In this respect, IRP has not performed the bridge role for the future retirement pension income. We provide an economic decision-making model of both government and workers, where the retirement benefits related with the IRP are explicitly considered. Our model is required to select specific severance pay systems to maximize the income security and stability for their future old ages. It is concluded that the need of workers on the severance pay system is automatically revealed into the switch to IRP when workers are out from their current jobs, which is equivalent to the effect of gradually unifying the dual system of the retirement payment. In additoin, our empirical data indicates the relatively higher probability of termination on IRP for the older male workers having the more retirement deposit.

• Journal of Korean Society of Transportation
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• v.27 no.6
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• pp.79-88
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• 2009

The objective of this study is to develop the new vehicle classification algorithm and minimize classification errors. The existing vehicle classification algorithm collects data from loop and piezo sensors according to the specification("Vehicle classification guide for traffic volume survey" 2006) given by the Ministry of Land, Transport and Maritime Affairs. The new vehicle classification system collects the vehicle length, distance between axles, axle type, wheel-base and tire type to minimize classification error. The main difference of new system is the "Wandering" sensor which is capable of measuring the wheel-base and tire type(single or dual). The wandering sensor obtains the wheel-base and tire type by detecting both left and right tire imprint. Verification tests were completed with the total traffic volume of 762,420 vehicles in a month for the new vehicle classification algorithm. Among them, 47 vehicles(0.006%) were not classified within 12 vehicle types. This results proves very high level of classification accuracy for the new system. Using the new vehicle classification algorithm will improve the accuracy and it can be broadly applicable to the road planning, design, and management. It can also upgrade the level of traffic research for the road and transportation infrastructure.

• Journal of the Korea Institute of Building Construction
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• v.11 no.6
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• pp.597-608
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• 2011

It has been often noted as a problem that as there are no objective and clear criteria for the repair cost estimate of persistent defects, when a claim arises in relation to an apartment construction, significantly different amounts of compensation may be given for similar defects based on the experience and tendencies of the construction experts asked to make a judgment. For this reason, this research aims to present defect managers with a more reasonable and objective estimation criteria and a system to determine the repair cost of defects based on an analysis of relevant factors. The research findings show that the historical cost system is applied first, and then a standard of estimation is used to estimate the cost for the items that are not included in the historical cost system. The criteria for the repair cost for each defect is as follows: the repair cost for defects arising from a regulation violation is determined by calculating the reconstruction cost of the parts in question after demolishing them; the repair cost for progressive defects is determined based on a contribution ratio proportional to the age of the building; the repair cost for repetitive defects is calculated by considering an alternative to maximize the intended function of the defective parts; and the repair cost for value depreciation defects is determined based on the ratio of the warranty period to the lapsed years. However, repair cost estimation for dual value depreciation defects should be studied in future research.

• 전자공학회논문지 IE
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• v.47 no.3
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• pp.19-25
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• 2010

We developed a RFID terminal to voice guide the blind who have difficulties in reaching out to the pharmaceutical information. In this work, we used RFID technology to instruct the pharmaceutical information to the blind. The voice guidance reader was made to read the RFID tag attached to the drugs and announced the pharmaceutical information matching to the tag specific ID. We had the reader to obtain the pharmaceutical information from the ezDrug site operated by Korea Food & Drug Association. The voice guidance reader was fabricated as necklace type for the easy carry, and we added mp3 player as dual uses. ARM series Cortex M3 chip was used for the reader's core chip and low power MFRC523 chipset of NXP was used to construct RFID circuit. MFRC523 chip uses low power to meet the mobile application. We used VS1003B MP3 Decoder IC to make the voice generation circuit and CC2500 chipset for the wireless communication to the pharmaceutical information server. We also developed the system that can support ISO 14443A type and ISO 14443B type so that the system can be used to extend to various RFID protocols. Utilization of this system can conveniently convey the pharmaceutical information to the blind and reduce the drug abuse.

• Journal of the Korean association of regional geographers
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• v.14 no.5
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• pp.536-552
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• 2008

In Korea, a variety of policies for the regional cultural industry development have been carried out: the promotion policy of cultural industry cluster, the establishment of cultural industry support center, and the construction of cultural industry complex and the supporting works for the cultural research center. The cultural industry has a dual character of the manufacturing industry and the service industry. The cultural industry of Gyeongbuk province is mostly centered upon small manufacturing firms with low value-added. Thus, it is desperately in need of the building-up of the enterprise supporting system. However, it is difficult to expect that private business service finns can be activated. In this sense, local and regional governments seek to establish so called 'the cultural contents support center'. However, it is not clear whether the center is an organization for the production of cultural contents or an agency for the support of cultural contents industry. Also it does not prepare any major functional introduction facilities and performing programs. Most of all, it is necessary to establish a proper orientation that 'the cultural contents support center' must be not an organization for the direct production of cultural contents, but an organization supporting cultural industry by way of providing cultural industry enterprises with what is necessary for the production of cultural contents. Also, a system for the establishment of business fitting support policy that can cover the whole sectors of cultural industry must be prepared. Furthermore, a synthetic support system for the cultural business associated industries centered on specified sectors such as films, edutainment, and storytelling must be constructed. Finally an environment for the creation and inducement of cultural industry enterprises, and for the active participation of enterprises and related groups in the promotion planning and in the policies of cultural industry must be built along with on- and off-line networks.

• The Korean Journal of Physiology and Pharmacology
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• v.11 no.1
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• pp.1-7
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• 2007

Altered environmental gravity, including both hypo- and hypergravity, may result in space adaptation syndrome. To explore the characteristics of this adaptive plasticity, the expression of immediate early gene c-fos mRNA in the vestibular related tissues following an exposure to hypergravity stimulus was determined in rats. The animals were subjected to a force of 2 g (twice earth's gravity) for 1, 3, or 12 h, and were examined poststimulus at 0, 2, 6, 12, and 24 h. RT-PCR (reverse transcription polymerase chain reaction) and real-time quantitative RT-PCR were adopted to analyze temporal changes in the expression of c-fos mRNA. The hypergravity stimulus increased the expression of c-fos mRNA in the vestibular ganglion, medial vestibular nucleus, inferior vestibular nucleus, hippocampus, cerebellum, and cortex. The peak expression occurred at 0 h poststimulation in animals stimulated with hypergravity for 1 h, and at 6 h poststimulus in those stimulated for 3 h. In contrast, those stimulated for 12 h exhibited dual peaks at 0 and 12 h poststimulus. Bilateral labyrinthectomy markedly attenuated the degree of c-fos mRNA expression. Glutamate receptor antagonist also dramatically attenuated the degree of c-fos mRNA expression. These results indicate that expression of c-fos mRNA in response to hypergravity occurs in the vestibular related tissues of the central nervous system, in which peripheral vestibular receptors and glutamate receptors play an important role. The temporal pattern of c-fos mRNA expression depended on the duration of the hypergravity stimulus.

• The KIPS Transactions:PartA
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• v.16A no.2
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• pp.69-78
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• 2009

One of the most effective way to improve cache performance is to exploit both temporal and spatial locality given by any program executive characteristics. In this paper we present a high performance and low power cache structure with a bank selection mechanism that enhances exploitation of spatial and temporal locality. The proposed cache system consists of two parts, i.e., a main direct-mapped cache with a small block size and a fully associative buffer with a large block size as a multiple of the small block size. Especially, the main direct-mapped cache is constructed as two banks for low power consumption and stores a small block which is selected from fully associative buffer by the proposed bank selection algorithm. By using the bank selection algorithm and three state bits, We selectively extend the lifetime of those small blocks with high temporal locality by storing them in the main direct-mapped caches. This approach effectively reduces conflict misses and cache pollution at the same time. According to the simulation results, the average miss ratio, compared with the Victim and STAS caches with the same size, is improved by about 23% and 32% for Mibench applications respectively. The average memory access time is reduced by about 14% and 18% compared with the he victim and STAS caches respectively. It is also shown that energy consumption of the proposed cache is around 10% lower than other cache systems that we examine.

• The Korean Society of Law and Medicine
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• v.23 no.2
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• pp.97-118
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• 2022

The use of diagnostic radiation in medical institutions is rapidly increasing. Accordingly, the collective effective dose is on the rise every year. Therefore, it is necessary to reduce the radiation exposure of the person undergoing the radiation examination as low as reasonably achievable. And we must establish a legal system to perform the safe management of radiation for diagnosis efficiently. In this way, I went over the problems of the Act and Subordinate Statutes regarding radiation safety management for diagnosis. As a result, the main contents are as follows. First, in the 「Medical Service Act」, there is no basis for the Safety Inspection Institute of Radiation and Radiation Exposure Measuring Institutes. And there are no provisions concerning delegation of administrative disposition. Therefore, it is necessary to secure legal justification by providing the basis for the Safety Inspection Institute of Radiation along with Radiation Exposure Measuring Institutes and the basis for administrative dispositions against these institutions in the 「Medical Service Act」. Second, the 「Rules on the Installation and Operation of Special Medical Equipment 」 should be integrated with the 「Rules on the Safety Management of Radiation Generators for Diagnostics」 to unify administrative procedures such as reporting for radiation special medical equipment for diagnosis. Third, in the case of violating the diagnostic radiation safety management standards in the 「Rules on the Safety Management of Radiation Generators for Diagnostics」, it is necessary to supplement the insufficient sanctions such as administrative disposition. Fourth, regulating diagnostic radiation and therapeutic radiation used in medical institutions with the dual legal system of the 「Medical Act」 and the 「Nuclear Safety Act」 is not efficient in the safety management of diagnostic radiation. Therefore, it is necessary to uniformly regulate diagnostic radiation and all medical radiation, including therapeutic radiation and nuclear medicine, in the 「Medical Service Act」 system.

• Journal of Aerospace System Engineering
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• v.16 no.3
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• pp.84-92
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• 2022

The electro-hydrostatic actuator (EHA) recently has been used in flight control fields for aircraft because of its benefits of minimizing oil leakage and weight, improving safety, and etc. while independently operating the hydraulic power source and eliminating complex hydraulic piping. The aircraft of which EHA is installed inside, has the thermal management issue of EHA, because of its limited cooling source as compared with the aircraft which installs the traditional central hydraulic system. So, the thermal analysis model which predicts the thermal characteristics of EHA, is required to resolve this thermal management issue. In this study, an oil circulation circuit inside the hydraulic power module comprised of hydraulic pump and electrical motor for EHA was applied. This is for the purpose of developing the internal rotary group of hydraulic power module, which operates under the conditions of high rotation speed and hydraulic pressure. After formulating an appropriate thermal analysis model, the thermal analysis results with oil cooled or no oil cooled hydraulic control module were compared and reviewed, for the purpose of predicting the thermal characteristics of EHA.