• Economic and Environmental Geology
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• v.53 no.2
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• pp.133-145
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• 2020

Soil in mine waste-rock fields, and at the pithead, sediments and farmlands around an abandoned mine in the Chungcheong Province of South Korea were investigated to assess the distribution of metallic elements and to understand the scope of the pollution. Reddening was observed from the mine up to a distance of 61 m. Losses of waste rock around the mine were assessed over a section of 1800 ㎥. Yellowish precipitates on the bottom of a stream were identified as ferrihydrite and goethite. For anions, a mean sulfate ion level over 773.6 mg/L was found during August in the river water samples. Mine drainage at the site was shown to have a pH of 4.9 and a sulfate concentration of 1557.8 mg/L during the August rainy season. A possible cause of the metallic element contamination in the mine is waste-rock loss, because mine waste-rock is located on the slope in this area. In conclusion, the total soil area to be treated, based on the amount that exceeded the recommended Korean soil pollution levels, was assessed to be 10,297 ㎡.

• Korean Journal of Head & Neck Oncology
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• v.16 no.2
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• pp.191-195
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• 2000

Objectives: Despite various attempts to preserve the normal voice in advanced laryngeal cancer, it is inevitable for many advanced laryngeal cancer patients to undergo total laryngectomy and thus making a trade off between quality and quantity of life. Laryngectomees are faced with voice loss, change in physical appearance and health deterioration which hinder their efforts to rehabilitate back into their family and employment leading to poor quality of life. The objectives of this study were to evaluate the quality of life in long term surviving laryngectomees to, define the factors which are most important in determining their present quality of life and to propose a theoretical model for quality of life after laryngectomy in Korea. Materials and Methods: From 1986 to 1995, 120 laryngectomees with no evidence of disease were followed up for at least 3years were evaluated. Each of 15 quality of life domains with a total of ten points were given for a quality of life score. Results: There was no significant difference in the physical-mental adaptation index such as general health and mental health between the laryngectomees and control group(p>0.05). However, social adaptation index such as social activity, occupational status and economic status for laryngectomees were significantly lower with 2.3, 3.5, and 4.4 points compared to control group with 8.5, 7.6, and 7.1 points respectively(p<0.05). Conclusion : Vocational and social rehabilitation should be emphasized with highest priority for improving their economic status and thus improving their quality of life.

• Journal of Navigation and Port Research
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• v.31 no.6
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• pp.509-514
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• 2007

The importance of the GPS is becoming larger and larger since it is one of the Global Navigation Satellite Systems and is regarded as a national infrastructure in the field positioning and timing Nowadays many researches avoiding and/or minimizing economic loss caused by unexpected fault of the GPS are being carried out because GPS fault can give a large impact on social security system as well as economic system NDGPS network which has been authorized by the Ministry of Marine and Fisheries provides services for marine users and evolved into a national infrastructure for GNSS users. Many researchers and engineers are doing research work in order to apply the NDGPS network to other fields. From this trend, it can be expected that the integrity and related functions for the NDGPS users will become more important than before. This paper analyzes integrity informations about the real GNSS fault and proposes method on integrity monitoring improvement of the DGPS reference station.

• Journal of Korea Port Economic Association
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• v.29 no.1
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• pp.47-66
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• 2013

This article reviews some problems arises from signing by the master bills of lading issued on time chartered ship. The underlying purpose of time charters is generally for the charterers to have the services of the vessel in order to engage in the business of carriage of goods by sea, a business which is likely to involve the issue of bills of lading to shippers. Charterer under the charter have a right to issue B/L, thereby the master must sign bill of lading as presented, but may not vary the contract. Bills of lading signed by, or on behalf of the master, impose contractual liabilities upon the shipowner. Charterer have no right to ask the master to sign a bill of lading in any way deviating from the charterparty. If the shipowner suffers loss as a result of the master obeying any order about employment or agency, he will be entitled to an indemnity from the charterer. The master may refuse to sign bills of lading which contain some discrepancy such as a false statement and manifestly inconsistent with the requirements of the charterparty.

• Transactions of Materials Processing
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• v.25 no.1
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• pp.12-20
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• 2016

Press machines and dies are commonly used for 3D curved sheet forming. Using conventional die forming can cause economic problems since various modifications of the die shape are required depending on the product shape. Various types of flexible forming such as multi-point dieless forming (MDF), flexible incremental roll forming have been developed to improve the needed process flexibility. Although MDF can reduce the production cost using reconfigurable dies, it still has significant material loss. Drawbacks such as wrinkling, dimpling, and forming errors can also occur despite continuous investigations to mitigate these defects. A novel sheet forming process for 3D curved surfaces, a flexibly-reconfigurable roll forming (FRRF), has been recently proposed to overcome the economic and technical limitations of current practice. FRRF has no limitation on blank size in the longitudinal direction, and also minimizes or eliminates forming defects such as wrinkling and dimpling. Feasibility studies of FRRF have been conducted using FE simulations for multi-curved shapes and various sheet thicknesses. Therefore, the fabrication of a FRRF apparatus is required for any follow-up studies. In the current study, experiments with reconfigurable rollers were conducted using a simple design pre-FRRF apparatus prior to fabricating the full size FRRF apparatus. There are three candidates for the reconfigurable roller: a bar-type shaft, a flexible shaft, a ground flexible shaft. Among these candidates, the suitable reconfigurable roller for FRRF is determined through various forming tests.

• Journal of Korean Academy of Nursing
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• v.13 no.2
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• pp.70-86
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• 1983

The purpose of study carried out to determine the effect of informativeness influeucing the state-Anxiety of Hysterectomy patient, the relationship between Hysterectomy patient's general characteristics on State-Anxiety. and to investigation the cause of hysterectomy patient's Anxiety, the relationship between the cause of Anxiety and State-Anxiety. This stuad carried out between April 14. to May 24. 1983. This study sample consisted of 104 Hysterectomy patient who admitted to department of obstetrics of Seoul National University Hospital, Korea University Hospital, Han Yang University Hospital and Seung Nam Hospital. The Sample were divided into two groups; fifty two of experimental and fifty two of control group. The method used for the collection of data were set of information prepared by reseacher and state-Anxiety Inventory, The Questionnaire of state-Anxiety Inventory was made up 20 items. The data was analyzed by computer program. The results of the study were as follows. 1. There was shown state Anxiety to be alleviated by experimental group and control group. 2. There was significant relation between experimental group and control group. (p<0.01) 3. There was relation of state-Anxiety by education Level: Experimental group (p＜0.05) control group (p<0.05) religion : only control group (p＜0.05)economic state : only control group (p<0.05) The people who encouraged hysterectomy: Experimental group (p<0.05) control group (p＜0.0001) 4. The cause of preoperative anxiety about hysterectomy were as follows: 1) destruction of body image(=loss of uterus) 2) husband's attitude 3) Expactation that hysterectomy will adversely affect sexual relation 5. Among the cause of Anxiety, R²for state-Anxiety were as follows: 1) economic state 17.3% 2) deatch 21.6% 3) Expactation that hysterectomy will adversely affect sexual relation 24.5%.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.10
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• pp.2230-2236
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• 2012

Currently, the AC-to-DC power conversion system using diode rectifiers is mainly used in large vessels. Also, to reduce the total harmonic distortion(THD) of current and voltage, this system requires an additional phase-shifting transformer which can be powered multi-pulses. In this case, due to the installation of the transformer, the spatial or economic loss occurs. This paper presents a novel active rectification scheme using silicon controlled rectifier(SCR) or insulated gate bipolar transistor(IGBT) devices on behalf of the diode rectifiers which are currently operating in large vessels such as LNG Carrier(LNGC). The proposed system can use the low voltage source and reduce current and voltage harmonics generated by nonlinear loads connected to the power distribution bus and save economic costs by removing the phase-shifting transformers which are used in conventional system. Computer simulations are performed under the electric propulsion system which is operating in current large vessel. The results are shown in support of the improvement of THD included in the current and voltage wave forms of propulsion motor.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.2
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• pp.197-207
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• 2018

SMEs manufacturing Factory, which are small-scale production systems of various types, mass-produce and sell products in order to meet customer needs. This means that the company has an excessive amount of material supply to reduce the loss due to lack of inventory and high inventory maintenance cost. And the products that fail to respond to the demand are piled up in the management warehouse, which is the reality that the storage cost is incurred. To overcome this problem, this paper uses ARIMA model, a time series analysis technique, to predict demand in terms of seasonal factors. In this way, demand forecasting model based on economic order quantity model was developed to prevent stock shortage risk. Simulation is carried out to evaluate the effectiveness of the development model and to demonstrate the effectiveness of the development model as applied to SMEs in the future.

• Journal of Korea Port Economic Association
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• v.33 no.1
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• pp.89-110
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• 2017

The organization of the shipping conference -an international cartel, was approved by countries that recognized it for stabilizing routes as well as preventing excessive competition among liner shipping companies and recognized the characteristic of the liner service that is regularly repeated in the international liner shipping market. However, due to competition in bulk transportation and development of multimodal transport through new entrants, power expansion and vessel enlargement of non-aligned shipping companies; the shipping conference started collapsing, and was eventually abolished. As the shipping conference played an important role in the liner shipping market, there were changes in the competition structure of the liner shipping market, and this accordingly drove research on the effects of the abolition of the shipping conference on the liner shipping market. The effects of abolition of the shipping conference on the liner shipping market was analyzed after surveying the factors related to abolition of the shipping conference, and through the use of correlation and multiple regression analyses. Subsequent to the abolition of the shipping conference, the liner shipping companies increased global containership bottoms. Consequently, this led to fierce competition of freight charges. As a result, profitability of shipping companies diminished. However, shipping companies with a dominating cost structure recorded profits, while shipping companies with an inferior cost structure started recording a loss.

• Economic and Environmental Geology
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• v.39 no.4 s.179
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• pp.427-440
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• 2006

Electromagnetic(EM) survey has been in use for over a half century as a standard routine for, mineral exploration in many parts of the world. But EM survey work and serious research effort were initiated in Korea only as late as in early 1980s, largely inspired by four pioneers who did their graduate studies in the U.S.A. in 1970s. Nevertheless domestic achievements in the field of EM survey are remarkable in the last two decades: the field operations and related interpretational skills appear to have reached a global standard, even compared with the most advanced in other countries, virtually in a whole spectrum of the method which includes magneto-tellurics(MT), Controlled Source Audio-frequency Magneto-tellurics(CSAMT), geomagnetic sounding, small loop survey systems, Very Low Frequency(VLF), Ground Penetrating Radar(GPR), time domain surveys, and noise analysis. Besides mineral exploration, EM survey has been applied in Korea to hydrogeology, geotechnical engineering, non-destructive investigation of structures, unexplored ordnance(UXO) investigation, environmental monitoring, and archaeological investigation as well. Now that original contributions of several Korean geophysicists are found even in new frontiers such as high-frequency EM survey, investigation in time-domain EM field for buried metal objects and structures, and also modem data inversion scheme, it is duly hoped that they make some technical breakthrough to unravel still entangled knots of EM survey method in a forseeable future.