• KIPS Transactions on Computer and Communication Systems
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• v.4 no.2
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• pp.47-56
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• 2015

In an energy saving server cluster environment, the power modes of servers are controlled according to load situation, that is, by making ON only minimum number of servers needed to handle current load while making the other servers OFF. This algorithm works well under normal circumstances, but does not guarantee QoS under abnormal circumstances such as sharply rising or falling loads. This is because the number of ON servers cannot be increased immediately due to the time delay for servers to turn ON from OFF. In this paper, we propose a new prediction algorithm of the power consumption for improving QoS under not only normal but also abnormal circumstances. The proposed prediction algorithm consists of two parts: prediction based on the conventional time series analysis and prediction adjustment based on trend analysis. We performed experiments using 15 PCs and compared performance for 4 types of conventional time series based prediction methods and their modified methods with our prediction algorithm. Experimental results show that Exponential Smoothing with Trend Adjusted (ESTA) and its modified ESTA (MESTA) proposed in this paper are outperforming among 4 types of prediction methods in terms of normalized QoS and number of good reponses per power consumed, and QoS of MESTA proposed in this paper is 7.5% and 3.3% better than that of conventional ESTA for artificial load pattern and real load pattern, respectively.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.9
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• pp.581-588
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• 2016

Piezoelectric thick films of a soft $Pb(Zr,Ti)O_3$ (PZT) based commercial material were produced by a conventional tape casting method. Thereafter, the interdigitated (IDT) Ag-Pd electrode pattern was printed on the $25{\mu}m$ thick piezoelectric film at room temperature. Co-firing of the 10-layer laminated piezoelectric thick films was conducted at $1,100^{\circ}C$ and $1,150^{\circ}C$ for 1 h, respectively. Piezoelectric cantilever energy harvesters were successfully fabricated using the IDT electrode pattern embedded piezoelectric laminates for 3-3 operation mode. Their energy harvesting characteristics were investigated with an excitation of 120 Hz and 1 g under various resistive loads (ranging from $10k{\Omega}$ to $200k{\Omega}$). A parabolic increase of voltage and a linear decrease of current were shown with an increase of resistive load for all the energy harvesters. In particular, a high output power of 3.64 mW at $100k{\Omega}$ was obtained from the energy harvester (sintered at $1,150^{\circ}C$).

• Tunnel and Underground Space
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• v.15 no.2 s.55
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• pp.157-167
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• 2005

Current initial rock stress state is one of the key factors required to evaluate the stability and failure around an excavated opening and its importance increases as the construction depth become deeper and the scale of the rock structure become larger. In this paper, the study was performed to evaluate the characteristics of the regional stress state at Chuncheon-Yanggu mountainous region, the East-North part of Kyeonggi Massif. Forty nine field stress measurements in 9 boreholes were conducted at the depth from 20 m to 290 m by hydraulic fracturing method. The fracturing tracing works were carried out by acoustic televiewer scanning. The study results revealed that the different intial rock stress states presented at different formation rock type and the excessive horizontal stress state with stress ratio(K) close to 3.0 was measured at the depth of 200 m and deeper in the intrusive unite body of the study area. The results from the investigation of excessive horizontal stress and its effect on failure mode showed that there exist several points where the localized excessive horizontal stresses are big enough to potentially induce brittle failures around the future openings greater than 100 m in depth within the granite body of the study area.

• Journal of Energy Engineering
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• v.8 no.4
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• pp.592-604
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• 1999

The steady state and dynamic characteristics of large cell area MCFC stacks were analyzed to solve the problems such as temperature difference generated in stacks and pressure difference between anode and cathode. Manipulated variables (current density, duel utilization rate, oxidant utilization rate) and controlled variables (temperature difference, anode and cathode pressure difference) which had an important effect on the MCFC stack performance were determined using operation results of two types of MCFC stacks (5kW (3,000 $\textrm{cm}^2$, 20 ea). 3kW (6,000 $\textrm{cm}^2$, 5ea)). The stability and transfer function representing system dynamics were obtained by steady state gain rate which showed the relative change between MVs and CVs. The transfer function was a 3$\times$3 matrix and a typical first order system without time delay. The optimal operating condition of large cell area MCFC stacks could be determined by analyzing dynamic characteristics. In case of a 5 kW MCFC stack, pressurized operation with recycle flow should be used to control the outlet temperature less than 68$0^{\circ}C$ and to control the MCFC system effectively. MIMO control or decoupler should be used to remove the interaction between MVs and CVs. This result will be used as important data in determining the control structure design and operation mode of large cell area MCFC systems in the future.

• Current Research on Agriculture and Life Sciences
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• v.5
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• pp.173-184
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• 1987

Anethole, eugenol, isoeugenol, safrole and isosafrole are ingredients of refined oils which are obtained from some plants and their chemical structures are very similar. They are mainly used as a flavoring agent, food additive, dental analgesics and for many drugs. But, there is no report about their effect on the intestinal motility. The result of examining the effect, potency and mode of action of anethole, eugenol, isoeugenol, safrole and isosafrole on motility of isolated rabbit jejunum segment, are as follows : 1. Single administration of anethole, eugenol, isoeugenol, safrole and isosafrole showed the inhibition of motility of isolated rabbit jejunum segment, degree of which was various. The $pD_2$ values of isoeugenol, isosafrole, eugenol, safrole and anethole in isolated rabbit jejunum segment were 4.22, 4.18, 4.17, 4.15 and 3.82 (in the descending order of potency). 2. The contracted rabbit jejunum segment : by carbachol, pilocarpine, barium chloride and histarmine were relaxed by five essential oil. 3. The relaxed rabbit jejunum segment by anethole was not recovered by carbachol, pilocarpine, barium chloride and histamine. The relaxed rabbit jejunum segment by eugenol, isoeugenol, safrole and isosafrole were recovered by carbachol, pilocarpine and barium chloride but partially recovered by histamine. 4. Judging from the facts above, it is thought that five essential oil are inhibit the motility of isolated rabbit jejunum segment by neurotropic and musculotropic action.

• Current Research on Agriculture and Life Sciences
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• v.32 no.3
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• pp.111-117
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• 2014

Phytophthora blight caused by Phytophthora capsici Leonian is a dangerous disease threatening pepper growers worldwide. The efficacy of chemical control is generally low as the pathogen is soil-borne and rapidly spread by zoospores during the rainy season. Thus, based on the demand for resistant varieties, various good resistant sources, such as CM334, AC2258, and PI201234, have been reported and their inheritance of resistance studied by many different authorities. However, the mode of inheritance remains unclear, as 1 or 2 independent dominant genes, 3 genes, or multiple genes have all been reported as responsible for resistance. Recently, QTL mappings of the gene factors for resistance have been reported, and molecular markers for resistance used in breeding programs. With the release of many resistant commercial hybrid cultivars, differentiation of pathotypes of the pathogen is attracting interest among breeders and plant pathologists. Various authorities have already classified the pathogen strains into different races according to the inter-action between resistant host plants, including the source of resistance, such as CM334 and PI201234, and resistant commercial varieties and P. capsici isolates. However, no standard differential host sets have yet been established, so the results are good only for the pathogen strains used in the experiments. Thus, for breeding varieties with durable resist-ance, it is important to introduce resistance from different sources and use diverse local pathogen strains collected in the target area for distribution in a breeding program.

• Journal of Korean Society of Transportation
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• v.23 no.2
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• pp.75-82
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• 2005

To relieve congestion in the current system of intercity transportation, the Korea decided in 1990 to construct a high-speed railroad between Seoul and Busan and it is now in operation. This new mode of transportation significantly cut travel time between major cities and a trip from Seoul to the southeastern port of Busan. Since the KTX opening, average daily passenger numbers on both the Gyeongbu and Honam lines have increased about 1.3 fold over 2003 levels. As of December 2004, the KTX trains are carrying about 81,000 people a day. On KTX routes, the daily number of airline passengers dropped. Express long-distance bus traffic also dropped by 20% to 30%, while that on short-distance routes (100km or less) increased by about 20%. These figures clearly indicate that the Korean transportation network is becoming railroad-centric. However, the number of KTX passengers is fewer than anticipated possibly due to the Korean economic downturn and the operation of the KTX will leave many existing Saemaul and Mugunghwa train sets idle, which will be put into operation for areas, not covered by the KTX. When all the existing major lines have been electrified, more high-speed rail services will be phased in using direct connections to maximize operational efficiency. And also, the dual management by KTX and conventional rail will be regarded as the promotion of the benefit of the public.

• Cross-Cultural Studies
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• v.34
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• pp.7-41
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• 2014

This article examines magical realism in contemporary european film, which is considered to be one of the most popular styles in the present culture, with regards to Antonio Negri's theory of art. Magical realism is "alternative approach to reality" (Maggie Ann Bowers, Magic(al) Realism) and defined as "a fictional technique that combines fantasy with raw physical reality or social reality in a search for truth beyond that available from the surface of everyday life" (Joan Mellen, Magic Realism). The term of Magic Realism was coined in 1923 by Franz Roh, German art historian, as the concept for the post-expressionist painting in Germany. It has flourished in the Latin-American literature during the 1950s to 1980s and spread worldwide. Since 1980s magical realism is considered to be a universal artistic mode. Since 1990s magical realism is to find in the various novels, and since 2000 one encounters magical realism in the cinema very often. Antonio Negri writes about the relationship between life, imagination, art and the political in his book Art et Multitude. According to Negri, the hard life of people in the present society liberates the imagination and this creates the art as "the excess of the existence". In this process the aesthetic becomes to the political. Negri calls this space of art as "magical time and space". Claire Denis' film Vendredi Soir is analyzed as a contemporary magic realist text, which realizes Negri's concept of art: vendredi soir (friday night) in Vendredi Soir is the magical time, when the impossible becomes the possible, and paris in the public transportation strike is the magical space, where the individuals meet the other in a new situation. The film analysis associates itself with Negri's theory of art: in Vendredi Soir, it is to see, that the excess of the existence liberates imagination and creates the magic reality both in the movements of things and the human relationship. The phenomenon of magical realism in contemporary culture can be understood as the symptom of the emotional and existential pains of contemporary people in the current world. The contemporaneity of the magical realism can be read in the film as "the metaphor for contemporary thought" (Alain Badiou, Cinema). As Antonio Negri writes, art can become "the aesthetic redemption" (Negri, Art et Multitude) for us. At the same time "(t)his is where aesthetics can be transformed into the political." (Lee, "Communism and the Void")

• Korean Journal of Remote Sensing
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• v.11 no.3
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• pp.101-116
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• 1995

The fact that the demands on traffic data collection are imposed by economic and safety considerations raisese the question of the potential for complementing existing traffic data collection programs with satellite data. Evaluating and monitoring traffic characteristics is becoming increasingly important as worsening congestion, declining economic situations, and increasing environmental sensitivies are forcing the government and municipalities to make better use of existing roadway capacities. The present system of using automatic counters at selected points on highways works well from a temporal point of view (i.e., during a specific period of time at one location). However, the present system does not cover the spatial aspects of the entire road system (i.e., for every location during specific periods of time); the counters are employed only at points and only on selected highways. This lack of spatial coverage is due, in part, to the cost of the automatic counters systems (fixed procurement and maintenance costs) and of the personal required to deploy them. The current procedure is believed to work fairly well in the aggregate mode, at the macro level. However, at micro level, the numbers are more suspect. In addition, the statistics only work when assuming a certain homogenity among characteristics of highways in the same class, an assumption that is impossible to test whn little or no data is gathered on many of the highways for a given class. In this paper, a remote sensing system as complement of the existing system is considered and implemented. Since satellite imagery with high resolution is not available, digitized panchromatic imagery acquired from an aircraft platform is utilized for initial test of the feasibility and performance capability of remote sensing data. Different levels of imagery resolutions are evaluated in an attempt to determine what vehicle types could be classified and counted against a background of pavement types, which might be expected in panchromatic satellite imagery. The results of a systematic study with three different levels of resolutions (1m, 2m and 4m) show that the panchromat ic reflectances of vehicles and pavements would be distributed so similarly that it would be difficult to classify systematically and analytically remotely sensing vehicles on pavement within panchromatic range. Anaysis of the aerial photographs show that the shadows of the vehicles could be a cue for vehicle detection.

• Journal of the Korean Society for Railway
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• v.17 no.5
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• pp.328-335
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• 2014

Numerical prediction methods were applied to investigate the turbulent air currents and air-conditioning efficiency in an underground subway station, and the results compared to experimental data. The Shin-gumho Station($8^{th}$ floor underground and 43.6m in depth) in Seoul was selected for the analysis. The entire station was covered for simulation and the ventilation mode was ordinary. The ventilation diffusers were modeled as 95 square shapes of $0.6m{\times}0.6m$ in the lobby and as 222 square shapes in the platform. Cooling air of $47,316m^3/h$ was supplied and the returned air of $33,980m^3/h$ is exhausted in the lobby and the cooling air of $33,968m^3/h$ is supplied and the returned air of $76,190m^3/h$ was exhausted in the platform which is the same as the experimental data. The cases of the screen-door-closed and open were respectively investigated. A total of 7.5million grids were generated and the whole domain divided into 22 blocks for MPI efficiency of calculation. Large eddy simulation (LES) was applied to solve the momentum and energy equation.