• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.12
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• pp.108-116
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• 2009

In this paper, we propose a Ethernet based audio distribution system with a new L1/L2 hybrid switching scheme, and evaluate its performance. The proposed scheme not only offers guaranteed low latency and jitter characteristics that are essentially required for the distribution of high-quality uncompressed audio traffic, and but also provide an efficient transmission of data traffic on the Ethernet environment. The audio distribution system with a proposed scheme consists of a master node and a number of relay nodes, and all nodes are mutually connected as a daisy-chain topology through up and downlinks. The master node generates an audio frame for each cycle of 125us, and the audio frame has 24 time slotted audio channels for carrying stereo 24 channels of 16-bit PCM sampled audio. On receiving the audio frame from its upstream node via the downlink, each intermediate node inserts its audio traffic to the reserved time slot for itself, then relays again to next node through its physical layer(L1) transmission - repeating. After reaching the end node, the audio frame is loopbacked through the uplink. On repeating through the uplink, each node makes a copy of audio slot that node has to receive, then play the audio. When the audio transmission is completed, each node works as a normal L2 switch, thus data frames are switched during the remaining period. For supporting this L1/L2 hybrid switching capability, we insert a glue logic for parsing and multiplexing audio and data frames at MII(Media Independent Interlace) between the physical and data link layers. The proposed scheme can provide a good delay performance and transmission efficiency than legacy Ethernet based audio distribution systems. For verifying the feasibility of the proposed L1/L2 hybrid switching scheme, we use OMNeT++ as a simulation tool with various parameters. From the simulation results, one can find that the proposed scheme can provides outstanding characteristics in terms of both jitter characteristic for audio traffic and transmission efficiency of data traffics.

• Journal of the Korean Geographical Society
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• v.28 no.1
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• pp.40-57
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• 1993

This paper aims to show the various aspects of migration in Kwangju merropolitan area, southwestern Korea, for a period of years 1980-1985. Migratory patterns are spatially extensive in countryside around Kwanfju, and due to high accessibility to the metropolitan area urban implosion emerges in the city. In Chonnam province where Kwangju is loca-ted, all cities and counties except for such in-dustrial areas as Yochon, and Kwangyang are experiencing population losses in terms of net migration by survival rate methods. Kwangju is the exceptionally one of in-migration areas in Chonnam, though its central part(Dong-Gu) is also an out-migrated area. Predominantly in-migration urban areas have high proportions of a student age group between 15-19 years, and that reflects the importance of the educational factor in migration analysis. The municipal authorities of Kwangju are planning to block the way of the middle sxhool students who live in the outskirts of Kwangju to entrance to high school in the city. Thant may stir up migrations into Kwangju for the elementary and middle school students, because the city id expected to provide educational opportunities higher and better than remaining Chonnam areas. Population of Kwangju would, therefore, grow as the students migrate into the city. The findings on the residential intra-city movement in selected 5 Dongs indicate that implications of a short-distance movement re noteworthy; neighbour to neighbour, and the nearest stop in the way from the outer Kwangju as well. Trends in a short-distance movement are in accord with Ravensteins's "law of migra-tion". But in casw of the inter-provincial migra-tion to Kwangju, the number of in-migrants from remoter Seoul is more than that from nearer Chonbuk province. Therefore it supports the fact that the movement between capital region and far off local cities overcomes a distance barrier. The temporary mobility for a day has been increased as the standard of living has improved and it reaches a peak on weekend or on con-secutive holidays. The number of temporal movers to Kwangju from capital region and Yongnam area, southeastern Korea has a greatincrease in terms of the frequency of the passengers' mobility, in particular on Myongjol(the ethnic and traditional festival day) in com-parison with on weekdays. By comparison with two largest Myongjols, the number of movers is more on Chusok(The Full Moon festival on lunar August) than on Sol (lunar new year's day). Annual peak point of weekday movers appears in August because of summer vacation. But the lowest one appears in June, which is related to the busy farming season. A patients' move for medical services in on the increase with a change of living conditions. It is especially true in the industrial counties such as Kwangyang and Yochon. By way of conclusion, it should be pointed out that one of the problems we face in survey of migration volume by the survival rate method is that the survival rate somtimes exceeds the value 1.0, in normal states of which should be under 1.0. it may be due to the shortcoming from the census statistics. We should not give therefore too much stress on the importance of migrations or moves as an element of changes in spatial pattern. In cinclusion, the results of the study show some geographic facts as the followings: 1. One of the outstanding phenomena in all types of movement is the seletivity of ages. The most important factors are related to education and employment. 2. Short-distance movement is carried out in accordance with Ravenstein's law, but in case long-distance movement, in-migration from capital region is prominent in spite of remoten-ces. The gravity between large cities such as Kwangju and Seoul, which has a frequent human movenent, causes urban implosion of small cities between those cities. 3. The temporary mobility for a day, in con-trast to that of permanent movement, is more related to transportation, and its volumes and annual variations are a large-scale. 4. Passengers' mobility is high in industrial cities. And the scope of patients' mobility is narrower than passengers'.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.44-63
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• 2000

Situated close to Heathrow Airport, and adjacent to the M4 and M25 Motorways, the site at Axis Park is considered a prime location for business in the UK. In consequnce two of the UK's major property development companies, MEPC and Redrew Homes sought the expertise of Intergeo to remediate the contaminated former industrial site prior to its development. Industrial use of the twenty-six hectare site, started in 1936, when Hawker Aircraft commence aircraft manufacture. In 1963 the Firestone Tyre and Rubber Company purchased part of the site. Ford commenced vehicle production at the site in the mid-1970's and production was continued by Iveco Ford from 1986 to the plant's decommissioning in 1997. Geologically the site is underlain by sand and gravel, deposited in prehistory by the River Thames, with London Clay at around 6m depth. The level of groundwater fluctuates seasonally at around 2.5m depth, moving slowly southwest towards local streams and watercourses. A phased investigation of the site was undertaken, which culminated in the extensive site investigation undertaken by Intergeo in 1998. In total 50 boreholes, 90 probeholes and 60 trial pits were used to investigate the site and around 4000 solid and 1300 liquid samples were tested in the laboratory for chemical substances. The investigations identified total petroleum hydrocarbons in the soil up to 25, 000mg/kg. Diesel oil, with some lubricating oil were the main components. Volatile organic compounds were identified in the groundwater in excess of 10mg/l. Specific substances included trichloromethane, trichloromethane and tetrachloroethene. Both the oil and volatile compounds were widely spread across the site, The specific substances identified could be traced back to industrial processes used at one or other dates in the sites history Slightly elevated levels of toxic metals and polycyclic aromatic hydrocarbons were also identified locally. Prior to remediation of the site and throughout its progress, extensive liaison with the regulatory authorities and the client's professional representatives was required. In addition to meetings, numerous technical documents detailing methods and health and safety issues were required in order to comply with UK environmental and safety legislation. After initially considering a range of options to undertake remediation, the following three main techniques were selected: ex-situ bioremediation of hydrocarbon contaminated soils, skimming of free floating hydrocarbon product from the water surface at wells and excavations and air stripping of volatile organic compounds from groundwater recovered from wells. The achievements were as follows: 1) 350, 000m3 of soil was excavated and 112, 000m3 of sand and gravel was processed to remove gravel and cobble sized particles; 2) 53, 000m3 of hydrocarbon contaminated soil was bioremediated in windrows ; 3) 7000m3 of groundwater was processed by skimming to remove free floating Product; 4) 196, 000m3 of groundwater was Processed by air stripping to remove volatile organic compounds. Only 1000m3 of soil left the site for disposal in licensed waste facilities Given the costs of disposal in the UK, the selected methods represented a considerable cost saving to the Clients. All other soil was engineered back into the ground to a precise geotechnical specification. The following objective levels were achieved across the site 1) By a Risk Based Corrective Action (RBCA) methodology it was demonstrated that soil with less that 1000mg/kg total petroleum hydrocarbons did not pose a hazard to health or water resources and therefore, could remain insitu; 2) Soils destined for the residential areas of the site were remediated to 250mg/kg total petroleum hydrocarbons; in the industrial areas 500mg/kg was proven acceptable. 3) Hydrocarbons in groundwater were remediated to below the Dutch Intervegtion Level of 0.6mg/1; 4) Volatile organic compounds/BTEX group substances were reduced to below the Dutch Intervention Levels; 5) Polycyclic aromatic hydrocarbons and metals were below Inter-departmental Committee for the Redevelopment of Contaminated Land guideline levels for intended enduse. In order to verify the qualify of the work 1500 chemical test results were submitted for the purpose of validation. Quality assurance checks were undertaken by independent consultants and at an independent laboratory selected by Intergeo. Long term monitoring of water quality was undertaken for a period of one year after remediation work had been completed. Both the regulatory authorities and Clients representatives endorsed the quality of remediation now completed at the site. Subsequent to completion of the remediation work Redrew Homes constructed a prestige housing development. The properties at "Belvedere Place" retailed at premium prices. On the MEPC site the Post Office, amongst others, has located a major sorting office for the London area. Exceptionally high standards of remediation, control and documentation were a requirement for the work undertaken here.aken here.

• Korean Journal of Ecology and Environment
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• v.43 no.2
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• pp.279-287
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• 2010

This study was to evaluate ecological conditions of Hyeongsan River watershed from April to September 2009. The ecological health assessments was based on Qualitative Habitat Evaluation Index (QHEI), water chemistry during 2000~2009, and the fish multi-metric model, Index of Biological Integrity (IBI). For the study, the models of IBI and QHEI were modified as 8 and 11 metric attributes, respectively. Values of IBI averaged 25.4 (n=6), which is judged as a "fair" condition (C) after the criteria of Barbour et al. (1999). The distinct spatial variation was found in the IBI. Physical habitat health, based on the values of QHEI, varied from 76 in the downriver (H6) to 150.5 in the headwater (H1) and was evidently more disturbed in the downriver reach. Values of BOD and COD averaged 2.4 $mgL^{-1}$ (range: 0.3~13.8 $mgL^{-1}$) and 4.3 $mgL^{-1}$ (scope: 0.6~12.8 $mgL^{-1}$), respectively during the study period. Total nitrogen (TN) and total phosphorus (TP) averaged 3.0 $mgL^{-1}$ and 103.5 ${\mu}gL^{-1}$, respectively, indicating a severe eutrophication, and the nutrients increased more in the downriver than the headwater. Overall, physical, chemical and IBI parameters showed a typical downriver degradation along main axis of the river from the headwater-to-the downriver. This was mainly attributed to livestock waste and residential influences along with industrial discharge from the urban region.

• Journal of the Korean Geographical Society
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• v.41 no.2 s.113
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• pp.168-187
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• 2006

Windy meteorological conditions and dried fire fuels due to higher atmospheric instability and dryness in the lower troposphere can exacerbate fire controls and result in more losses of forest resources and residential properties due to enhanced large wildland fires. Long-term (1979-2005) climatology of the Haines Index reconstructed in this study reveals that spatial patterns and intra-annual variability of the atmospheric instability and dryness in the lower troposphere affect the frequency of wildland fire incidences over the Korean Peninsula. Exponential regression models verify that daily high Haines Index and its monthly frequency has statistically significant correlations with the frequency of the wildland fire occurrences during the fire season (December-April) in South Korea. According to the climatic maps of the Haines Index created by the Geographic Information System (GIS) using the Digital Elevation Model (DEM), the lowlands below 500m from the mean sea level in the northwestern regions of the Korean Peninsula demonstrates the high frequency of the Haines Index equal to or greater than five in April and May. The annual frequency of the high Haines Index represents an increasing trend across the Korean Peninsula since the mid-1990s, particularly in Gyeongsangbuk-do and along the eastern coastal areas. The composite of synoptic weather maps at 500hPa for extreme events, in which the high Haines Index lasted for several days consecutively, illustrates that the cold low pressure system developed around the Sea of Okhotsk in the extreme event period enhances the pressure gradient and westerly wind speed over the Korean Peninsula. These results demonstrate the need for further consideration of the spatial-temporal characteristics of vertical atmospheric components, such as atmospheric instability and dryness, in the current Korean fire prediction system.

• Journal of the Korean association of regional geographers
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• v.5 no.2
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• pp.47-117
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• 1999

This study concern with the pattern of Pusan Station shopping district within Pusan City, Korea, one of the special functioned shopping district within Pusan City. This paper will serve as a part of series studies which attempt to clarify the internal structure of Pusan as a whole. Part(II) of this study deals with the functions including living related, restaurants and others. The pattern of floors, size of shops, street corners and widths of streets were also analysed. The results are as follows: 1. In terms of numbers of firms in living related function, Pusan Station shopping district is the $7{\sim}8th$ ranked central place among nine the highest centers within Pusan City. Pusan Station shopping district has not much promoted vertical spatial differentiation comparatively, and also it's intensity of land use is the lower among nine the highest centers. It is presented that intimate relationship between intensity of vertical land use and classes of central places within the city. The ratio of inns and hotels in Pusan Station shopping district is third ranked in Pusan City. And the size of inns and hotels in this area is the most largest among the nine highest ranked central places within Pusan City. These presented that the traditional characteristics of station area as a special functioned shopping district. Inns and hotels mainly located along the narrower and back street. And it forms agglomerated areas or 'an alley of inns' at the inner parts of blocks, some like a 'hidden flower'. In Korea, 'alley' means that an area of specialization gains the prestige, traditionally. 2. Restaurants mainly locate along the narrower and back streets. And agglomerated areas of restaurants coincide with the agglomerated area of drinking places. It shows that these two kinds of functions need the same locational conditions. The ratio of Chinese restaurants is the highest in the Pusan Station shopping district. It's due to the agglomerated area these kinds of restaurants at the 'China town'. 3. Pusan Station shopping district has been formed along the streets within the residential areas. It's means that this shopping district now at the initial or middle growth era in development stage of shopping areas. 4. In general, wholesales and light manufacturing are located at peripheries within shopping district. But in Pusan Station shopping district, it dose not appear these spatial pattern. It shows that this area is lower ranked central place and not much progressed in spatial differentiation. 5. Particular firms which customers and workers have stayed more longer period of time are located at the far from the first floor. This vertical spatial differentiation is similar to the horizontal sequences. 6. Firms which have more ability of rental payment are located at street comers such as banks and pharmacies. In Pusan Station shopping district commercial facilities could not invade into the second third floors at narrower streets and first floor of back streets, still now.

• Journal of the Korean Institute of Landscape Architecture
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• v.42 no.6
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• pp.101-110
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• 2014

This study analyzes the validity of the type classification of the type and design changes of apartment landscaping planting construction design changes that were completed in the private sector, efficiently manages the design changes that are displayed over landscaping planting work in general in the future, and performs research by placing the object underlying the presentation. The results are as follows. First, the percentage that occurred in the planting construction of design changes that have occurred in the apartment landscaping construction was carried out in the private sector and accounted for 61.8%. This indicates that part of the planting is a major design change. Second, as the cause of such a design change to be those associated with the field conditions such as lack of main construction period. In particular, due to a change in oral, appeared 7-48 times design changes of one review design change approval is complex, design changes of planting construction had shown a feature that occurs in multiple simultaneous. Third, the 7 types of Design Changes in planting design were delineated as 'design changes for consideration of the user', 'design changes for image improvement', 'design changes for ease of maintenance', 'design changes due to the mismatch of design statement', 'design changes due to the relationship with the engineering species of other', 'design changes due to lack of field study', and 'design changes due to the consideration of feasibility.' Fourth, 'design changes for consideration of the user' and 'design changes for image improvement' were found in more than half of the frequency of the overall changes. This differed from the results shown in public corporations. Fifth, if planting construction design change process, private companies, it was found that is showing the approval of the practice after the previous construction of the construction cost savings due to construction time. However, in the case of a public corporation, these exhibited a different aspect from the private sector and show a design change procedure that reflects the changes after the design change events in the field have occurred. The above results, the type of landscaping works in planting design change of public enterprises, regardless of the private sector, is the same in the seven types, the main reason of and procedures for design changes, indicating that there are other respects. In design change, it may be desirable to apply becomes liquidity rationality and efficiency of the dimension, depending on the nature of the landscape construction.

• Journal of Ginseng Culture
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• v.1
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• pp.11-27
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• 2019

The Jurchens, the ancestors of the Qing Manchus, had lived scattered in Manchuria and had made their living mostly on ginseng gathering and animal hunting. Their residential areas, rich with deep forest and numerous rivers, provided great habitation for all kinds of flora and fauna, but not so proper for agriculture. Based on their activities of foraging and hunting, the Jurchens developed a unique social organization that was later transformed into the Banner System, the most distinctive Qing military institution. By the sixteenth century, that the external trade brought considerable changes to Jurchen society. A huge amount of foreign silver, imported from Japan and South America to China, first invigorated commercial economy in China proper, and later caused a huge influence on Ming frontier regions, including Manchuria. In the late sixteenth century when the tradition of foraging and hunting encountered with silver economy, the Jurchen tribes became unified after years of competition and transformed themselves into the Manchus to build the Qing empire in 1636. In 1644 the Manchus succeeded in conquering the China Proper and moved into Beijing. Even after that, the Manchu imperial court never forgot the value of Manchurii ginseng; instead, they paid great efforts to monopolize this profitable root. Until the late seventeenth century, the Qing court used the Banner System to manage Manchurian ginseng. The banner soldiers stationed in Manchuria checked unauthorized civilian entrances in this frontier and protected its ginseng producing mountains from the Han Chinese people. All the process of ginseng gathering was managed by the institutions under the direct control of the imperial court, such as the Imperial Household Department, the Butha Ula Office, and the Three Upper Banner in Shengjing. Banner soldiers were dispatched to the given mountains, collect the given amount of ginseng, and send them to the imperial court in Beijing. The state monopoly of ginseng was maintained throughout the eighteenth and nineteenth centuries under the principle that Manchuria and its natural resources should be guarded from civilian encroachment. At the same time, Manchurian ginseng was considered as an important source of state revenue. The imperial court and financial bureau wanted to collect ginseng as much as they needed. By the late seventeenth century as the ginseng management by the banner soldiers failed in securing the ginseng tax, the Qing court began to invite civil merchants to ginseng business. During the eighteenth century the Qing ginseng policy became more dependent on civil merchants, both their money and management. In 1853 the Qing finally ended the ginseng monopoly, but it was before the early eighteenth century that wealthy merchants hired ginseng gatherers and paid ginseng tax to the state. The Qing monopoly of ginseng was in fact maintained by the active participation of civil merchants in the ginseng business.

• (The)Study of the Eastern Classic
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• no.62
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• pp.231-262
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• 2016

The Jongmyo Shrine(宗廟) of Zhou dynasty was a king's main building where a diversity of rituals were held, such as 'the assembly ceremony between a king and vassals in the morning', and was also called as Taechim(太寢) Nochim(路寢) Jeongchim(正寢) and others. Before Zhou dynasty, the expressions of Taesil(太室) and Sesil(世室) were used, and especially the term of Taesil(太室) is found in the records of the early period of West Zhou. In "Seogyeong(書經)", not only the term of Nochim(路寢) but also the letter of 'chim(寢)' itself is not found at all, but the letter of 'sil(室)' appeared several times in the chapters of "Haseo(夏書)" "Sangseo(商書)" "Juseo(周書)" except for that of "Wuseo(虞書)". "Jwajowusa(左祖右社)" meaning that 'the Jongmyo Shrine(宗廟) which keeps the late king's mortuary tablet is established in the left, and Sajikdan altar(社稷壇) which enshrines a god of land and grains is established in the right' was first mentioned in the part of 'Janginyeongguk(匠人營國 : a master craftsman builds different national infrastructures, for instance, a palace and roads)' in "Donggwangogonggi(冬官考工記)" of "Jurye(周禮)". In addition, so-called 'Jwamyowusa(左廟右社)', that is, "Sajik(社稷) enshrining the god of land and grains is built in the right('右'), and the Jongmyo Shrine(宗廟) in the left('左'). (右社稷 左宗廟)" was mentioned as one of different duties of a Sojongbaek(小宗伯) in charge of ancestral rites, which was recorded in "Chungwanjongbaek(春官宗伯)" of "Jurye(周禮)". And it seems that had affected the mention of "Jwajowusa(左祖右社)" in "Donggwangogonggi(冬官考工記)" appeared thereafter. Many manners scholars including Jeonghyun(鄭玄) since Han dynasty interpreted 'Jwa(左 : left)' and 'Wu(右 : right)' here as the arrangement relation of left and right of Jongmyo(宗廟) and Sajik(社稷), but when it is interpreted as "helping(右=佑 : to help) to sacrifice to a god of land and grains in Sajik(社稷), and helping(左=佐 : to help) memorial ceremonies in Jongmyo(宗廟)." it can correspond with a 'Jongbaek(宗伯)''s duties. 'Jeonmyohuchim(前廟後寢)' is the term that began from the expression that "what's in front is called as an jongmyo shrine(宗廟) and what's back as a bedroom.(前曰廟 後曰寢)" in Jeonghyun(鄭玄)'s annotation explaining the chapter of "Hagwansama(夏官司馬)" in "Jurye(周禮)" and "Wolryeong(月令)" in "Yegi(禮記)". Chaeong(蔡邕), a figure in the same age as Jeonghyun(鄭玄), used the expression that "a court is placed in the front, and a bedroom in the back(前有朝 後有寢)." In the paper, two hypotheses were discussed about the theory about Jeonmyohuchim(前廟後寢). In one hypothesis, it expressed two facilities within a wall; 'a court in the front to deal with governmental affairs, and a comfortable interior space in the back.' In another hypothesis, it refers to two independent and separate buildings of 'an jongmyo shrine(宗廟) building in the front as the area of governmental meetings, and the residential building in the back as the residence area with family'.

• The Journal of Engineering Geology
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• v.30 no.4
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• pp.457-468
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• 2020

Problems arising during pile design works for plant construction, civil and architecture work are mostly come from uncertainty of geotechnical characteristics. In particular, obtaining the N-value measured through the Standard Penetration Test (SPT) is the most important data. However, it is difficult to obtain N-value by drilling investigation throughout the all target area. There are many constraints such as licensing, time, cost, equipment access and residential complaints etc. it is impossible to obtain geotechnical characteristics through drilling investigation within a short bidding period in overseas. The geotechnical characteristics at non-drilling investigation points are usually determined by the engineer's empirical judgment, which can leads to errors in pile design and quantity calculation causing construction delay and cost increase. It would be possible to overcome this problem if N-value could be predicted at the non-drilling investigation points using limited minimum drilling investigation data. This study was conducted to predicted the N-value using an Artificial Neural Network (ANN) which one of the Artificial intelligence (AI) method. An Artificial Neural Network treats a limited amount of geotechnical characteristics as a biological logic process, providing more reliable results for input variables. The purpose of this study is to predict N-value at the non-drilling investigation points through patterns which is studied by multi-layer perceptron and error back-propagation algorithms using the minimum geotechnical data. It has been reviewed the reliability of the values that predicted by AI method compared to the measured values, and we were able to confirm the high reliability as a result. To solving geotechnical uncertainty, we will perform sensitivity analysis of input variables to increase learning effect in next steps and it may need some technical update of program. We hope that our study will be helpful to design works in the future.