• The KIPS Transactions:PartD
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• v.19D no.1
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• pp.1-14
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• 2012

As the size of the data warehouse is large, the selection of indices on the data warehouse affects the efficiency of the query processing of the data warehouse. Indices induce the lower query processing cost, but they occupy the large storage areas and induce the index maintenance cost which are accompanied by database updates. The bitmap join indices are well applied when we optimize the star join queries which join a fact table and many dimension tables and the selection on dimension tables in data warehouses. Though the bitmap join indices with the binary representations induce the lower storage cost, the task to select the indexing attributes among the huge candidate attributes which are generated is difficult. The processes of index selection are to reduce the number of candidate attributes to be indexed and then select the indexing attributes. In this paper on bitmap join index selection problem we reduce the number of candidate attributes by the data mining techniques. Compared to the existing techniques which reduce the number of candidate attributes by the frequencies of attributes we consider the frequencies of attributes and the size of dimension tables and the size of the tuples of the dimension tables and the page size of disk. We use the mining of the frequent itemsets as mining techniques and reduce the great number of candidate attributes. We make the bitmap join indices which have the least costs and the least storage area adapted to storage constraints by using the cost functions applied to the bitmap join indices of the candidate attributes. We compare the existing techniques and ours and analyze them in order to evaluate the efficiencies of ours.

• Management & Information Systems Review
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• v.36 no.3
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• pp.185-202
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• 2017

This study suggests the estimation of the demand for the exhibition center in Busan and to valid reasons for the establishment of the 2nd Convention Center in Busan. The validity for the estimated demand is acquired by examining the studies conducted by the Ministry of Commerce Industry and Energy. The qualitative data for the phased establishment of the area is suggested in accordance to the results of the demand estimation. From previous study(Oh, 2017), Kangseo-gu, Busan has been evaluated to be the final candidate for building a new convention center in the city of Busan. The potential synergy effects of on-going developmental projects in Kangseo region is one of the influential factors for the MICE professionals' opinion in the qualitative analysis. Moreover, the region has available land to hold the facility of more than 100,000 square meter to overcome the current drawback of BEXCO, insufficient space to hold large events. Lastly, the expansion of Gimhae International Airport would bring an increased international flights that would also lead to an increase in MICE industry for the region. The virtual effect of the more than one million $m^2$-sized oconvention center is examined via Huff Model and the results suggests a logical estimated data for further demand needed for the south east regions, not just within the city of Busan.

• Journal of East-West Nursing Research
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• v.2 no.1
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• pp.96-106
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• 1997

In Chinese medicine, the activities of removing and solving the inner cause are called the regimen in preventing the disease and the good condition of mind emphasizes us to practice ourselves the doctrine of regimen of the mind to promote the health and long life of the living body, in other words, it means we should have clean mind, less desire, less thought, less agony and widely open our emotion and will, and it also means the raising of good nature, the moral cultivation, and we can be healthy when we live by good virtus as the root of regiem. The meaning of the Qi has been expanded more and more since its origination throught the process of practice and perception of man. 1) Matter is changed to the smoke when burned, the energy of water becomes the rain in the sky and the rain raises all living creatures by making them wet. Throught these changes of circulation, men could realize the energy to be the common and original matter of forming all the creatures. 2) The direction of showing the breathing of men in and out has been expended. 3) It was widely understood as the meaning of showing vitality of men, and it was the original root of chinese medicine. 4) It was expended to be showing spirit of nature such as the sun, moon, star, sky, land, mountain and the moral spirit of men as peacefullness. By the original meaning of the word of energy expanded to the wider side of sky, land, men and things, nature, society, man and the moral spirit could get the unified basis of the matter. As the above, the word of Qi has been used in wider meaning at this time from the past. In other words, all things in the universe come into being and extinct by the chang of motion of the Qi and it is recognized to be the living activity in human body. The Qi-kong based on this energy and the motion applied to our daily life are very extensive (Lee, Hye - lung, 1997). Here are the summaries of the effect of the Qi-kong ; 1) The physical constitution is strenthened, physiological function is prosperous and we are free from various geriatric disease and psychosomatic disease not to mention the cold and indigestion. 2) It maintains the clear spirit, elevates intelligence, strengthens the spiritual power and demonstrates the potentiality at the amximum. 3) It maintain beautiful figure and clean skin never losing the charm but full of energy and vitality. 4) It keeps the balanced body never suffering from the unbalance of the bones, various and neuralgia. 5) It maintain the spiritual comfort, the natural posture in everything and real happiness (Lee, Hye-Jung, 1997 : Suh, Yong Kyu, 1989). Chinese medicine mentions the motion by Qi with Qi - kong. But the motion does not require special method in Western medicine. I t is the only way of living of our ancestor indaily life. It is maintaining the healthy lifr by training the Qi, and it is the motion of being with the nature with the open mind in breathing rather than artificially restricting our daily life, it is the motion of the body.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.8 no.3
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• pp.205-215
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• 2013

Job creations through doing star-ups is the biggest issues for almost nations. This study explores the entrepreneurial university's rule for making job creations based on Smart specialization and entrepreneurial university perspectives. In order to the aims, this study reviews the previous literatures and examines the some Israel universities, which is Technion University, Hebrew university as well as government support policies. Technion University and Hebrew university have own technology transfer institutions composed of experts for technology transfer and doing start-ups by using technologies. Each institutions have own characteristics regarding technology transfer and doing start-ups. T3, which is technology transfer institution of Technion University facilitates the start-up by step-by-step supporting mechanism. T3 has been operating EIR which has focused on business and marketing. Yissum, which is technology transfer institution of Hebrew university has board members. they have crucial roles to success the start ups. they can reconciliate the conflicts between university and Yissum. Also they can participate the business activities as mentors. Start-up money will be supported for even sprout state technology if their technologies are a promising business. Risk sharing between universities and start-ups influences on the increase of success ratio in Israel when comparing to that of Korea.

• The Journal of Dong Guk Oriental Medicine
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• v.5
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• pp.281-306
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• 1996

A study on the effect of the Sun-Moon-Stars(日月星辰) in Huang Ti Nei Ching("黃帝內經") on the formation of the Yunqi theory(運氣理論) have revealed following conclusions. 1. There was a record of Stars(星辰) written by Gabgol-Character(甲骨文字) in the Yin(殷) Dynasty. But the very first documentary records of Stars(星辰) is Shu Jing("書經"). Ancient astronomy had the tendency of astrology of combined with theory of the Five Elements(五行) and finally effects the theory of formation of Huang Ti Nei Ching("黃帝內經"). 2. Shu Jing("書經") said that Junrak(錢樂) made an Armillary sphere(運天儀) in the Sung(宋) Dynasty. And in the Jin(秦) and the Han(漢) Dynasty, they already observed the stars. The Sunkiokhyung(璿機玉衡) which is machinery of star-observing, became to be called an Armillary sphere (運天儀) by the pass of times. 3. As of the theory of the Cosmos-structure(宇宙-構造論) in Ohanunhangdaeron("五運行大論"), Guiyugu(鬼兒區) announced the Hypothesis of Covering Heaven(蓋天說) but Kibak(岐伯) supported the Hypothesis of chaosheven's(蓋天說) and in the theory of atmosphere(大氣論) in Ohanunhangdaeron("五運行大論") said that the earth was in Great Empty(太虛) and it was floating in the universe by the Great Chi(大氣). 4. The knowledge about the Five stars(五星) in Huang Ti Nei Ching("黃帝內經") is presented in the section of Gemgwejineonron("金?眞言論"), Gigoupyondaeron("氣交變大論"), Youkwonjeonggidaeron("六元正紀大論").ln the method of identifying the Five stars(五星) presented the criteria of the brightness, the altitude, the colours and the orbit etc. 5. The jupiter which has twelve year's revolution cycle was the basis of determination on the Twelve constellation(12辰), the Twelve field of heaven(12次), the Twelve Houses in the ecliptic(黃道 12宮), the Twelve Earth's Branches(12支) and the Twelve fields of Earth(12分野) and also it became the origin of the duodecimals(12進法). 6. The saturn having about twenty-eight year's revolution cycle became the criterion in identifying the Twenty Eight Constellations(28宿) which was used as the coordinates of the Celestial sphere (天球). 7. By the Percussional movement(歲差運動), the position of polaris and the Vernal-Antumal equinox(春秋分点) were shifted. Therefore the ancient the Heaven Gate-Earth Door(天門-地戶) changed from the position of Sil-Byuk(室壁), Yik-Jin(翼軫). And the precisional movements brought about the concept of the WunHoyYunSe(元會運世) that is a method of dividing a period. Also the precisional movement gave three dimension(三次元) foundation interpreted the Sixty JiaZi (六十甲子) which is revolving through sixty years uniformally. 8. The Hypothesis of the Nine Houses and Eight Winds(九宮八風論) which is one field of the astrology of ancient polaris-nine Houses divination plate(太一九宮占盤) brought about the concept of deficiency and excess and the concept of the Wind Vice(風邪). In the Calendar System(曆法) presented in Huang Ti Nei Ching("黃帝內經") the tropical year of the Sun-Moon-Stars(日月星辰) and the revolution and the rotation of the earth give explanations the changes of Yin-Yang(陰陽) by the use of the ten Celestial branches(十干) and the twelve Earth branches(十二支).

• Journal of Digital Convergence
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• v.15 no.7
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• pp.181-190
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• 2017

The purpose of This study was to find out the effects of the hotel advertising attitude and brand image on customers' purchase intention. For this study, a total of 306 questionnaires among collected data for customers who experience hotel service at five star hotels located in Seoul from April 1, 2015 to April 30, 2015 was to ensure a valid sample. As a result of the experiments which conducted by factor analysis and regression analysis, it shows positive significant effects in purchase intention of "feeling and persuade attitude factor" and "reputation and usefulness attitude factor", but it is not positively effected continual purchase intention in hotel customers. Also, it shows positive significant effects on hotel customers' purchase intention of "emotional brand image" and "physical brand image". From the study, it is expected to find efficient ways to activate purchase intention on hotel products through differentiated advertising and brand image. In addition, it should be considered that positive images building up emotional and physical characteristics in hotels for establishing consumer-brand relationship. From the study, it is expected to find efficient ways to activate purchase intention on hotel products through differentiated advertising and brand image.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.7
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• pp.53-61
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• 2008

Consider a typical wireless sensor network in which stem nodes form the backbone network of mesh topology while each stem node together with leaf nodes in its vicinity forms a subnetwork of star topology. In such a wireless sensor network, we must heed the following when we design a MAC scheme supporting the packet delivery from a leaf node to a stem node. First, leaf nodes are usually battery-powered and it is difficult to change or recharge their batteries. Secondly, a wireless sensor network is often deployed to collect and update data periodically. Late delivery of a data segment by a sensor node causes the sink node to defer data processing and the data segment itself to be obsolete. Thirdly, extensive signaling is extremely limited and complex computation is hardly supported. Taking account of these facts, a MAC scheme must be able to save energy and support timeliness in packet delivery while being simple and robust as well. In this paper, we propose a version of ALOHA as a MAC scheme for a wireless sensor network. While conserving the simplicity and robustness of the original version of ALOHA, the proposed version of ALOHA possesses a distinctive feature that a sensor node decides between stop and continuation prior to each delivery attempt for a packet. Such a decision needs a stopping rule and we suggest a Bayes stopping rule. Note that a Bayes stopping rule minimizes the Bayes risk which reflects the energy, timeliness and throughput losses. Also, a Bayes stopping rule is practical since a sensor node makes a decision only using its own history of delivery attempt results and the prior information about the failure in delivery attempt. Numerical examples confirm that the proposed version of ALOHA employing a Bayes stopping rule is a useful MAC scheme in the severe environment of wireless sensor network.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.469-474
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• 2002

In recent years, modularization of engine parts has increased the application of plastic products in air intake systems. Plastic intake manifolds provide many advantages including reduced weight, contracted cost, and lower intake air temperatures. These manifolds, however, have some weakness when compared with customary aluminium intake manifolds, in that they have low sound transmission loss because of their lower material density. This low transmission loss of plastic intake manifolds causes several problems related to flow noise, especially when the throttle is opened quickly. The physical processes, responsible for this flow noise, include turbulent fluid motion and relative motion of the throttle to the airflow. The former is generated by high-speed airflow in the splits between the throttle valve and the inner-surface of the throttle body and surge-tank, which can be categorized into the quadrupole source. The latter induces the unsteady force on the flow, which can be classified into the dipole source. In this paper, the mechanism of noise generation from the turbulence is only investigated as a preliminary study. Stochastic noise source synthesis method is adopted for the analysis of turbulence-induced, i.e. quadrupole noise by throttle at quick opening state. The method consists of three procedures. The first step corresponds to the preliminary time-averaged Navier-Stokes computation with a $k-\varepsilon$ turbulence model providing mean flow field characteristics. The second step is the synthesis of time-dependent turbulent velocity field associated with quadrupole noise sources. The final step is devoted to the determination of acoustic source terms associated with turbulent velocity. For the first step, we used market available analysis tools such as STAR-CD, the trade names of fluid analysis tools available on the market. The steady state flows at three open angle of throttle valve, i.e. 20, 35 and 60 degree, are numerically analyzed. Then, time-dependent turbulent velocity fields are produced by using the stochastic model and the flow analysis results. Using this turbulent velocity field, the turbulence-originated noise sources, i.e. the self-noise and shear-noise sources are synthesized. Based on these numerical results, it is found that the origin of the turbulent flow and noise might be attributed to the process of formulation and the interaction of two vortex lines formed in the downstream of the throttle valve. These vortex lines are produced by the non-uniform splits between the throttle valve and inner cylinder surface. Based on the analysis, we present the low-noise design of the inner geometry of throttle body.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.559-563
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• 2015

Monitor of All-sky X-ray Image (MAXI) is a Japanese X-ray all-sky surveyer mounted on the International Space Station (ISS). It has been scanning the whole sky since 2009 during every 92-minute ISS rotation. X-ray transients are quickly found by the real-time nova-search program. As a result, MAXI has issued 133 Astronomer's Telegrams and 44 Gamma-ray burst Coordinated Networks so far. MAXI has discovered six new black holes (BH) in 4.5 years. Long-term behaviors of the MAXI BHs can be classified into two types by their outbursts; a fast-rise exponential-decay type and a fast-rise flat-top one. The slit camera is suitable for accumulating data over a long time. MAXI issued a 37-month catalog containing 500 sources above a ~0.6 mCrab detection limit at 4-10 keV in the region ${\mid}{b}{\mid}$ > $10^{\circ}$. The SSC instrument utilizing an X-ray CCD has detected diffuse soft X-rays extending over a large solid angle, such as the Cygnus super bubble. MAXI/SSC has also detcted a Ne emission line from the rapid soft X-ray nova MAXI J0158-744. The overall shapes of outbursts in Be X-ray binaries (BeXRB) are precisely observed with MAXI/GSC. BeXRB have two kinds of outbursts, a normal outburst and a giant one. The peak dates of the subsequent giant outbursts of A0535+26 repeated with a different period than the orbital one. The Be stellar disk is considered to either have a precession motion or a distorted shape. The long-term behaviors of low-mass X-ray binaries (LMXB) containing weakly magnetized neutron stars are investigated. Transient LMXBs (Aql X-1 and 4U 1608-52) repeated outbursts every 200-1000 days, which is understood by the limit-cycle of hydrogen ionization states in the outer accretion disk. A third state (very dim state) in Aql X-1 and 4U 1608-52 was interpreted as the propeller effect in the unified picture of LMXB. Cir X-1 is a peculiar source in the sense that its long-term behavior is not like typical LMXBs. The luminosity sometimes decreases suddenly at periastron. It might be explained by the stripping of the outer accretion disk by a clumpy stellar wind. MAXI observed 64 large flares from 22 active stars (RS CVns, dMe stars, Argol types, young stellar objects) over 4 years. The total energies are $10^{34}-10^{36}$ erg $s^{-1}$. Since MAXI can measure the spectrum (temperature and emission measure), we can estimate the size of the plasma and the magnetic fields. The size sometimes exceeds the size of the star. The magnetic field is in the range of 10-100 gauss, which is a typical value for solar flares.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.665-669
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• 2015

The Kepler mission has shown that small planets are extremely common. It is likely that nearly every star in the sky hosts at least one rocky planet. We just need to look hard enough-but this requires vast amounts of telescope time. MINERVA (MINiature Exoplanet Radial Velocity Array) is a dedicated exoplanet observatory with the primary goal of discovering rocky, Earth-like planets orbiting in the habitable zone of bright, nearby stars. The MINERVA team is a collaboration among UNSW Australia, Harvard-Smithsonian Center for Astrophysics, Penn State University, University of Montana, and the California Institute of Technology. The four-telescope MINERVA array will be sited at the F.L. Whipple Observatory on Mt Hopkins in Arizona, USA. Full science operations will begin in mid-2015 with all four telescopes and a stabilised spectrograph capable of high-precision Doppler velocity measurements. We will observe ~100 of the nearest, brightest, Sun-like stars every night for at least five years. Detailed simulations of the target list and survey strategy lead us to expect $15{\pm}4$ new low-mass planets.