• Title/Summary/Keyword: Well logging

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English Predicate Inversion: Towards Data-driven Learning

  • Kim, Jong-Bok;Kim, Jin-Young
    • Journal of English Language & Literature
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    • v.56 no.6
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    • pp.1047-1065
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    • 2010
  • English inversion constructions are not only hard for non-native speakers to learn but also difficult to teach mainly because of their intriguing grammatical and discourse properties. This paper addresses grammatical issues in learning or teaching the so-called 'predicate inversion (PI)' construction (e.g., Equally important in terms of forest depletion is the continuous logging of the forests). In particular, we chart the grammatical (distributional, syntactic, semantic, pragmatic) properties of the PI construction, and argue for adata-driven teaching for English grammar. To depart from the arm-chaired style of grammar teaching (relying on author-made simple sentences), our teaching method introduces a datadriven teaching. With total 25 university students in a grammar-related class, students together have analyzed the British Component of the International Corpus of English (ICE-GB), containing about one million words distributed across a variety of textual categories. We have identified total 290 PI sentences (206 from spoken and 87 from written texts). The preposed syntactic categories of the PI involve five main types: AdvP, PP, VP(ed/ing), NP, AP, and so, all of which function as the complement of the copula. In terms of discourse, we have observed, supporting Birner and Ward's (1998) observation that these preposed phrases represent more familiar information than the postposed subject. The corpus examples gave us the three possible types: The preposed element is discourse-old whereas the postposed one is discourse-new as in Putting wire mesh over a few bricks is a good idea. Both preposed and postposed elements can also be discourse new as in But a fly in the ointment is inflation. These two elements can also be discourse old as in Racing with him on the near-side is Rinus. The dominant occurrence of the PI in the spoken texts also supports the view that the balance (or scene-setting) in information structure is the main trigger for the use of the PI construction. After being exposed to the real data and in-depth syntactic as well as informationstructure analysis of the PI construction, it is proved that the class students have had a farmore clear understanding of the construction in question and have realized that grammar does not mean to live on by itself but tightly interacts with other important grammatical components such as information structure. The study directs us toward both a datadriven and interactive grammar teaching.

Study on Token based KMS for Information Sharing (정보 공유를 위한 토큰 기반 KMS 연구)

  • Sung-Hwa Han;Hoo-Ki Lee
    • Convergence Security Journal
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    • v.23 no.5
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    • pp.29-34
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    • 2023
  • KMS (Knowledge Management System) is used by various organizations to share information. This KMS includes important information as well as basic information used by each organization. To protect infortant information stored in KMS, many KMS use user identification and authentication features. In such a KMS security environment, if the account information of a user who can access the KMS is leaked, a malicious attacker using the account information can access the KMS and access all authorized important information. In this study, we propose KMS with user access control function that can protect important information even if user account information is leaked. The KMS with the user access control function proposed in this study protects the stored files in the KMS by applying an encryption algorithm. Users can access important documents by using tokens after logging in. A malicious attacker without a Token cannot access important files. As a result of checking the unit function for the target user access control function for effectiveness verification, it was confirmed that the access control function to be provided by KMS is normally provided.

Groundwater Systems in Seoul Area : Analysis of Hydraulic Properties (서울지역 지하수 시스템 조사 : 수리적 특성 분석)

  • 김윤영;이강근;성익환
    • The Journal of Engineering Geology
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    • v.8 no.1
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    • pp.51-73
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    • 1998
  • Hydrogeological systems in a metrnpolitan area can be understood by analyzing the groundwater disturbing factors such as constructions and land applications, the groundwater usage for domestic and industrial purposes, and the groundwater pumpage to lower the groundwater level for the structural safety of subway and underground facilities. This study is part of the study performed to understand the groundwater system in the Seoul area and it is focusing on the hydraulic properties. Groundwater well inventory, barometric efficiency measurements, pumping and slug tests, and long-term groundwater monitoring have been perfonrmed during the last 2 years. The relations between Han River and the groundwater around the river also have been observed. These observations and test data, together with the information on soil distribution, geology, and logging data are used to construct a database and GIS(Geographic Information System) presentation system using ARC/INFO. Barometric efficiencies appeared to have no special trends associated with well depths, which maeans that the degree of confinement of the crystaline rock aquifer of the Seoul area is distributed locally depending on the developrnent of fractures. Hydraulic conductivities exponentialiy decrease with well depth. The stage of Han River fluctuates according to the tidal movement of nearby seawater but the tidal effects attenuate due to the underwater dams. Groundwater levels in the Seoul area seem to have declined for the last two years,but it is not certain that the declination represents the long-term trend.

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The Analysis of Geothermal Gradient at Icheon Hot Spa Area (이천 온천원보호지구의 지온경사 해석)

  • Lee, Chol-Woo;Moon, Sang-Ho
    • The Journal of Engineering Geology
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    • v.18 no.2
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    • pp.185-190
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    • 2008
  • Nine wells have been developed for uses of thermal waters at the Icheon hot spa area. Drilling depths of those hot spring wells range from 166 to 294 m and their piezometric heads are located at about 50 m below the surface. Using the differences between the surface and bottom temperatures within all boreholes, we can simply estimate geothermal gradient in this area. Thus, we obtained the highest, lowest and average gradient values as $64^{\circ}C/km$ from SB-2 well, $45^{\circ}C/km$ from SB-1 well and approximately $54.28^{\circ}C/km$, respectively. However, observing the MRD-2 well additionally drilled into the depth of 996 m, we found out that this study area has widely experienced the temperature disturbance due to thermal groundwater penetration through the fracture systems within the depth of 720 m. Unlikely this phenomenon, we can conclude that the groundwater flow below the depth of 720 m does not exist. Therefore, using only those temperature data below the 720 m depth, we can estimate reasonable geo-thermal gradient values as $33^{\circ}C/km$ in this study area. Pumping test shows that outflowing temperature is $36^{\circ}C$ corresponding to the temperature logging data at 720 m depth.

Variation Characteristics of Hydraulic Gradient and Major Flow Direction in the Landfill Soils (매립지 토양층의 수리경사와 주 흐름 방향의 변동특성)

  • Kim, Tae-Yeong;Kang, Dong-Hwan;Kim, Sung-Soo;Kwon, Byung-Hyuk
    • Journal of Environmental Science International
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    • v.18 no.3
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    • pp.315-323
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    • 2009
  • Hydraulic gradient of the landfill soils is estimated by Devlin (2003) method, and its variation characteristics from rainfall and permeability of the aquifer material are analyzed. The study site of 18 m $\times$ 12 m is located in front of the Environment Research Center at the Pukyong National University, and core logging, slug/bail test and groundwater monitoring was performed. The sluglbail tests were performed in 9 wells (except BH9 well), and drawdown data with elapsed time for bail tests were analyzed using Bouwer-Rice and Hvorslev methods. The average hydraulic conductivity estimated in each of the test wells was ranged $1.991{\times}10^{-7}{\sim}4.714{\times}10^{-6}m/sec$, and the average hydraulic conductivity in the study site was estimated $2.376{\times}10^{-6}m/sec$ for arithmetic average, $1.655{\times}10^{-6}m/sec$ for geometric average and $9.366{\times}10^{-7}m/sec$ for harmonic average. The permeability of landfill soils was higher at the east side of the study site than at the west side. Groundwater level in 10 wells was monitored 44 times from October 2 to November 7, 2007. The groundwater level was ranged 1.187$\sim$1.610 m, and the average groundwater level range in each of the well showed 1.256$\sim$1.407 m. The groundwater level was higher at the east side than at the west side of the study site, and this distribution is identify to it of hydraulic conductivity. The hydraulie gradient and the major flow direction for 10 wells were estimated 0.0072$\sim$0.0093 and $81.7618{\sim}88.0836^{\circ}$, respectively. Also, the hydraulic gradient and the major flow direction for 9 wells were estimated 0.0102$\sim$0.0124 and $84.6822{\sim}89.1174^{\circ}$, respectively. The hydraulic gradient of the study site increased from rainfall (83.5 mm) on October 7, causing by that the groundwater level of the site with high permeability was higher. The hydraulic gradient estimated on and after October 16 was stable, due to almost no rainfall. Thus, it was confirmed that the variation of the hydraulic gradient in the landfill soils was controlled by the rainfall.

Empirical Rock Strength Logging in Boreholes Penetrating Sedimentary Formations (퇴적암에 대한 경험적 암석강도 추정에 대한 고찰)

  • Chang, Chan-Dong
    • Geophysics and Geophysical Exploration
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    • v.7 no.3
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    • pp.174-183
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    • 2004
  • The knowledge of rock strength is important in assessing wellbore stability problems, effective sanding, and the estimation of in situ stress field. Numerous empirical equations that relate unconfined compressive strength of sedimentary rocks (sandstone, shale, and limestone, and dolomite) to physical properties (such as velocity, elastic modulus, and porosity) are collected and reviewed. These equations can be used to estimate rock strength from parameters measurable with geophysical well logs. Their ability to fit laboratory-measured strength and physical property data that were compiled from the literature is reviewed. While some equations work reasonably well (for example, some strength-porosity relationships for sandstone and shale), rock strength variations with individual physical property measurements scatter considerably, indicating that most of the empirical equations are not sufficiently generic to fit all the data published on rock strength and physical properties. This emphasizes the importance of local calibration before one utilizes any of the empirical relationships presented. Nonetheless, some reasonable correlations can be found between geophysical properties and rock strength that can be useful for applications related to wellhole stability where haying a lower bound estimate of in situ rock strength is especially useful.

Development of the PC Based Color Fish Finder (퍼스널 컴퓨터를 이용한 칼라 어군탐지기의 개발에 관한 연구)

  • 신현옥
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.31 no.3
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    • pp.247-255
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    • 1995
  • This paper describes a personal computer(PC) based color fish finder to improve some problem of the commercial one. The commercial fish finder has no function of the echo data logging and replaying. The authors developed two types of the PC based color fish finder. One is a master type composed of a PC, a digital input-output board, and analog to digital converting (A/D) board and an ultrasonic transceiver unit, the other is a slave type composed of a PC and an A/D board. To test the performances of the master type experiments were carried out in air and in a water tank. It is found that the designed master type fish finder displays very well an eight-colored echogram by one dot resolution to the left side of the PC monitor. Also, the depth of echo signal was corresponds very well to the range from the transducer to a target. The sampling interval of echo signal is about 0.1m and the time of A/D conversion is 30 $\mu$sec. On the other hand, to test the performances of the slave type a raw data of echo signals from a data logger was supplied directly or via RF transceivers to the slave type one. From this experiment, it is confirmed the slave type is useful to replay the echo signal from the data logger or a telesounder.

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Assessment of CO2 Geological Storage Capacity for Basalt Flow Structure around PZ-1 Exploration Well in the Southern Continental Shelf of Korea (남해 대륙붕 PZ-1 시추공 주변 현무암 대지 구조의 CO2 지중저장용량 평가)

  • Shin, Seung Yong;Kang, Moohee;Shinn, Young Jae;Cheong, Snons
    • Economic and Environmental Geology
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    • v.53 no.1
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    • pp.33-43
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    • 2020
  • CO2 geological storage is currently considered as the most stable and effective technology for greenhouse gas reduction. The saline formations for CO2 geological storage are generally located at a depth of more than 800 m where CO2 can be stored in a supercritical state, and an extensive impermeable cap rock that prevents CO2 leakage to the surface should be distributed above the saline formations. Trough analysis of seismic and well data, we identified the basalt flow structure for potential CO2 storage where saline formation is overlain by basalt cap rock around PZ-1 exploration well in the Southern Continental Shelf of Korea. To evaluate CO2 storage capacity of the saline formation, total porosity and CO2 density are calculated based on well logging data of PZ-1 well. We constructed a 3D geological grid model with a certain size in the x, y and z axis directions for volume estimates of the saline formation, and performed a property modeling to assign total porosity to the geological grid. The estimated average CO2 geological storage capacity evaluated by the U.S. DOE method for the saline formation covered by the basalt cap rock is 84.17 Mt of CO2(ranges from 42.07 to 143.79 Mt of CO2).

Study of Geological Log Database for Public Wells, Jeju Island (제주도 공공 관정 지질주상도 DB 구축 소개)

  • Pak, Song-Hyon;Koh, Giwon;Park, Junbeom;Moon, Dukchul;Yoon, Woo Seok
    • Economic and Environmental Geology
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    • v.48 no.6
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    • pp.509-523
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    • 2015
  • This study introduces newly implemented geological well logs database for Jeju public water wells, built for a research project focusing on integrated hydrogeology database of Jeju Island. A detailed analysis of the existing 1,200 Jeju Island geological logs for the public wells developed since 1970 revealed six major indications to be improved for their use in Jeju geological logs DB construction: (1) lack of uniformity in rock name classification, (2) poor definitions of pyroclastic deposits and sand and gravel layers, (3) lack of well borehole aquifer information, (4) lack of information on well screen installation in many water wells, (5) differences by person in geological logging descriptions. A new Jeju geological logs DB enabling standardized input and output formats has been implemented to overcome the above indications by reestablishing the names of Jeju volcanic and sedimentary rocks and utilizing a commercial, database-based input structured, geological log program. The newly designed database structure in geological log program enables users to store a large number of geology, well drilling, and test data at the standardized DB input structure. Also, well borehole groundwater and aquifer test data can be easily added without modifying the existing database structure. Thus, the newly implemented geological logs DB could be a standardized DB for a large number of Jeju existing public wells and new wells to be developed in the future at Jeju Island. Also, the new geological logs DB will be a basis for ongoing project 'Developing GIS-based integrated interpretation system for Jeju Island hydrogeology'.

The Seismic Hazard Study on Chung-Nam Province using HAZUS (HAZUS를 이용한 충남지역의 지진피해 연구)

  • Kang, Ik-Bum;Park, Jung-Ho
    • Journal of the Korean Society of Hazard Mitigation
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    • v.2 no.2 s.5
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    • pp.73-83
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    • 2002
  • HAZUS developed by FEMA is applied to estimation on seismic hazard in Chung-Nam Province using basic data on general building, population, and geology of well-logging. Through the investigation on historical and instrumental earthquakes in Korean Peninsula seismic hazard is estimated in Chung-Nam Province in two ways for calculation of acceleration, deterministically and probabilistically. In deterministic method seismic hazard in Chung-Nam Province is estimated by generation of the maximum event that occurs in Hongsung and has magnitude of 6.0. According to the result, Hongsung Gun, Yesan Gun, and Boryung City are the most severe in building damage. The expected number of people who need hospitalization in Hongsung Gun and Yesan Gun due to the earthquake are 1.1 and 0.4, respectively. In probabilistic(return period of 5,000 year) method seismic hazard in Chung-Nam Province is estimated. According to the result, Gongju City is the most severe in building damage. The expected number of people who need hospitalization in Gongju City and Nonsan City due to the earthquake are 0.1 and 0.15, respectively.