• Title/Summary/Keyword: Full-of-Potential Method

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Magnetism of Pd(111) Thin Films: A First-principles Calculation (Pd(111) 박막의 자성: 제일원리계산)

  • Hong, Soon Cheol
    • Journal of the Korean Magnetics Society
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    • v.26 no.1
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    • pp.1-6
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    • 2016
  • Pd has the highest magnetic susceptibility among single element metals and often shows ferromagnetism under some special environments. In this paper, we report magnetism of 5- and 9-monolayers (ML) calculated by using full-potential linearized augmented plane wave method. Exchange-correlation interaction is taken into account in local density approximation (LDA) and generalized gradient approximation (GGA) and calculational results in LDA and GGA are compared with each other. It is found that calculations by LDA are more reliable compared to those by GGA because LDA prediction of paramagnetism of bulk Pd is consistent with experiments, whereas GGA predicts wrongly ferromagnetim of bulk Pd. Calculational results in LDA on a 5-ML Pd(111) thin film shows a ferromagnetic ground state unlike a paramagnetic ground state of bulk Pd. The center Pd layer of the 5-ML Pd(111) thin film has the largest magnetic moment ($0.273{\mu}_B$) among the layers and |m| = 1 orbital states play a dominant role in stabilizing the ferromagnetism of the 5-ML Pd(111) thin film. A 9-ML Pd(111) thin film in a ferromagnetic state has almost the same total energy as in a paramagnetic state. Since the magnetization of the 9-ML Pd(111) thin film is stable, the ferromagnetic state may be meta-stable.

Analysis of a Weak Zone in Embankment Close to a Drainage using Resistivity Monitoring Data (전기비저항 모니터링을 이용한 저수지 제체 취수시설 취약성 해석)

  • Lim, Sung Keun
    • Geophysics and Geophysical Exploration
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    • v.21 no.1
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    • pp.8-14
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    • 2018
  • For the purpose of maintenance and prevention of earth fill dams against damage from natural hazards, automatic monitoring through various measuring instruments and resistivity survey has been carried out. Reservoirs and embankments have the structural vulnerability on the agricultural usages since most of them were built more than thirty years ago. The main aim to use monitoring method is to verify the safety and integrity of the dam. Resistivity survey can detect potential weaknesses, such as defective zones, anomalous seepages or internal erosion processes. Permanent resistivity monitoring systems were installed at a reservoir, which daily measurements have been taken every 6 hour. Using monitoring data for one year, anomalous seepage and structural defects were clarified for dam safety. Annual water level fluctuations are around 10 m. During their operation, reservoir dams are subject to a never-ending hydraulic load from the reservoir, which over the years may cause changes in the properties of the inner parts of the dam construction. Detailed analysis of the monitoring results was performed and showed that resistivities at most locations have been very stable over the full monitoring period excluding the effects of water fluctuation and seasons. To investigate the detectability of weak zone using the DC resistivity monitoring, numerical modeling with a simplified model for the drainage at a reservoir dam was also performed. The results showed that the seepage zone near drainage in a reservoir dam could be detected by resistivity response change.

Design of Bias Circuit for Measuring the Multi-channel ISFET (다채널 ISFET 측정용 단일 바이어스 회로의 설계)

  • Cho, Byung-Woog;Kim, Young-Jin;Kim, Chang-Soo;Choi, Pyung;Sohn, Byung-Ki
    • Journal of Sensor Science and Technology
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    • v.7 no.1
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    • pp.31-38
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    • 1998
  • Multi-channel sensors can be used to increase the reliability and remove the random iloise in ion-sensitive field effect transistors(ISFETs). Multi-channel sensors is also an essential step toward potential fabrication of sensors for several ionic species in one device. However, when the multi-channel sensors are separately biased, the biasing problems become difficult, that is to say, the bias circuit is needed as many sensors. In this work, a circuit for biasing the four pH-ISFETs in null-balance method, where bias voltages are switched, was proposed. The proposed concept is need only one bias circuit for the four sensors. Therefore it has advantages of smaller size and lower power consumption than the case that all sensors are separately biased at a time. The proposed circuit was tested with discrete devices and its performance was investigated. In the recent trend, sensor systems are implemented as portable systems. So the verified measurement circuit was integrated by using the CMOS circuit. Fortunately, ISFET fabrication process can be compatible with CMOS process. Full circuit has a mask area of $660{\mu}m{\times}500{\mu}m$. In the future, this step will be used for developing the smart sensor system with ISFET.

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Analyzing animation techniques used in webtoons and their potential issues (웹툰 연출의 애니메이션 기법활용과 문제점 분석)

  • Kim, Yu-mi
    • Cartoon and Animation Studies
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    • s.46
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    • pp.85-106
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    • 2017
  • With the media's shift into the digital era in the 2000s, comic book publishers attempted a transition into the new medium by establishing a distribution structure using internet networks. But that effort shied from escaping the parallel-page reading structure of traditional comics. On the other hand, webtoons are showing divers changes by redesigning the structure of traditional sequential art media; they tend to separate and allot spaces according to the vertical scroll reading method of the internet browser and include animations, sound effects and background music. This trend is also in accordance with the preferences of modern readers. Modern society has complicated social structures with the development of various media; the public is therefore exposed to different stimuli and shows characteristics of differentiated perceptions. In other words, webtoons display more relevant and entertaining characteristics by inserting sounds and using moving texts and characters in specific frames, while traditional comics require an appreciation of withdrawal and immersion like other published media. Motions in webtoons are partially applied for dramatic tension or to create an effective expression of action. For example, hand-drawn animation is adopted to express motions by dividing motion images into many layers. Sounds are also utilized, such as background music with episode-related lyrics, melodies, ambient sounds and motion-related sound effects. In addition, webtoons provide readers with new amusement by giving tactile stimuli via the vibration of a smart phone. As stated above, the vertical direction, time-based nature of animation motions and tactile stimuli used in webtoons are differentiated from published comics. However, webtoons' utilization of innovative techniques hasn't yet reached its full potential. In addition to the fact that the software used for webtoon effects is operationally complex, this is a transitional phenomenon since there is still a lack of technical understanding of animation and sound application amongst the general public. For example, a sound might be programmed to play when a specific frame scrolls into view on the monitor, but the frame may be scrolled faster or slower than the author intended; in this case, sound can end before or after a reader sees the whole image. The motion of each frame is also programmed to start in a similar fashion. Therefore, a reader's scroll speed is related to the motion's speed. For this reason, motions might miss the intended timing and be unnatural because they are played out of context. Also, finished sound effects can disturb the concentration of readers. These problems come from a shortage of continuity; to solve these, naturally activated consecutive sounds or animations, like the simple rotation of joints when a character moves, is required.

A Study on Gradual Attitudes Change College of Nursing Students (간호대학생의 학년별 태도 변화에 관한 연구)

  • 한정석
    • Journal of Korean Academy of Nursing
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    • v.3 no.2
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    • pp.121-132
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    • 1973
  • Introduction : Nursing as a profession is gelling wide acceptance today, especially among independent -minded women with necessary physical, mental and academic qualifications. This is particularly true of "comprehensive nursing", which requires to total dedication on the part if the nurse herself-physical, mental and sociocultural. Such comprehensive approach is like-wise called for in the institutional training of professional nurses. Undergraduate nursing courses nowadays place an increasing emphasis on the microscopic approach of training a nurse as an intelligent and well-balanced human being with an optimum degree of cultural sophistication. Greater attention then ever before is now paid to close observation of the individual traits and aptitude of nursing students, so as to permit full development of individual capabilities, interests and propensities within the concept of "comprehensive human education. " Purpose of study 1. To determine the degree of understanding of the part of nursing students of the various aspects of the subject taught in undergraduate nursing course. 2. To determine the motivation of nursing students in choosing the profession and possible subsequent change or attitude and outlook in the course of under graduated studies, as a means of presenting a new practical approach in nursing training based on the concept of "comprehensive human education. " Problems of study 1. The environments of nursing training will impinge on individual nursing students with different psychological impacts from lower to upper classes of under graduated studies. 2. Educational environments will have varying psychological impacts on students: a. Difference in religious faith among students. b. Difference in campus environments. c. Difference in domestic (family) circumstances. d. Difference in innate capabilities of students, 3. The understanding and attitude of individual nursing students towards the science of nursing will Have a close correlation with their respective motivations in choosing-nursing as a profession, and will also be closely influenced by the peculiarities of the subject taught, tile campus environments, etc, Delimitations of the study 1. Two universities offering 4-year nursing courses were selected. Due to the limited number of potential subjects, the optimum conditions of sample collection could not be fulfilled. 2. Subjects were confined to two classes in each university (sophomores and seniors) but without regard to the ages or scholastic achievements of individual students. 3. The conclusions derived from this study should be limited in application to the subject groups covered by the present study: they should not in any event be extended or applied to other groups. Procedures 1. Subjects: 40 nursing students each from the sophomore and senior classes of the "Y" and "K" universities situated in Seoul, aggregating 160 students altogether. 2. Instruments: Use has been made of questionnaires on (1) family backgrounds and (2) general information concerning. 3. Statistical Method: The findings of the present survey have been subjected to critical analysis as to the means, percentages, Cgi squares (X), standard deviations and the significance of the difference in means. Findings 1. Nursing students have chosen their subject of study with a confident outlook towards their future in society. 2. Horsing students have the necessary abilities to complete the prescribed courses of study. 3. The campus life of nursing students has been judged as very constructive, not with-standing certain in adequacies in the available educational facilities and the shortages of teaching staff. 4. The achievement levels of nursing trainees varied greatly according to their respective educational environments as well as their school years. 5. Clear and definite distinctions were discernible between the two universities as regards certain aspects of this survey, while no signifiant difference was observed in other: a. Sophomores and seniors in both universities gave nearly identical answers to questions concerning (1) motivation in choosing nursing as a profession, and (2) the way of spending leisure hours. b. Both universities revealed similar respective differences between sophomores and seniors as regards the abilities of fulfilling academic requirements ill the basic subjects. c. Educational environments have been found to be somewhat superior in the "Y"university to those of the "K" university, particularly as regard general campus and dormitory conditions. d. The high degree of dissatisfaction with the faculty, found in both universities, was considered to be a consequence of the universal phenomenon of "brain drain" and the relative neglect of the "comprehensive approach"in education.

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Underpricing of Initial Offerings and the Efficiency of Investments (신주(新株)의 저가상장현상(低價上場現象)과 투자(投資)의 효율성(效率成)에 대한 연구(硏究))

  • Nam, Il-chong
    • KDI Journal of Economic Policy
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    • v.12 no.2
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    • pp.95-120
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    • 1990
  • The underpricing of new shares of a firm that are offered to the public for the first time (initial offerings) is well known and has puzzled financial economists for a long time since it seems at odds with the optimal behavior of the owners of issuing firms. Past attempts by financial economists to explain this phenomenon have not been successful in the sense that the explanations given by them are either inconsistent with the equilibrium theory or implausible. Approaches by such authors as Welch or Allen and Faulhaber are no exceptions. In this paper, we develop a signalling model of capital investment to explain the underpricing phenomenon and also analyze the efficiency of investment. The model focuses on the information asymmetry between the owners of issuing firms and general investors. We consider a firm that has been owned and operated by a single owner and that has a profitable project but has no capital to develop it. The profit from the project depends on the capital invested in the project as well as a profitability parameter. The model also assumes that the financial market is represented by a single investor who maximizes the expected wealth. The owner has superior information as to the value of the firm to investors in the sense that it knows the true value of the parameter while investors have only a probability distribution about the parameter. The owner offers the representative investor a fraction of the ownership of the firm in return for a certain amount of investment in the firm. This offer condition is equivalent to the usual offer condition consisting of the number of issues to sell and the unit price of a share. Thus, the model is a signalling game. Using Kreps' criterion as the solution concept, we obtained an essentially unique separating equilibrium offer condition. Analysis of this separating equilibrium shows that the owner of the firm with high profitability chooses an offer condition that raises an amount of capital that is short of the amount that maximizes the potential profit from the project. It also reveals that the fraction of the ownership of the firm that the representative investor receives from the owner of the highly profitable firm in return for its investment has a value that exceeds the investment. In other words, the initial offering in the model is underpriced when the profitability of the firm is high. The source of underpricing and underinvestment is the signalling activity by the owner of the highly profitable firm who attempts to convince investors that his firm has a highly profitable project by choosing an offer condition that cannot be imitated by the owner of a firm with low profitability. Thus, we obtained two main results. First, underpricing is a result of a signalling activity by the owner of a firm with high profitability when there exists information asymmetry between the owner of the issuing firm and investors. Second, such information asymmetry also leads to underinvestment in a highly profitable project. Those results clearly show the underpricing entails underinvestment and that information asymmetry leads to a social cost as well as a private cost. The above results are quite general in the sense that they are based upon a neoclassical profit function and full rationality of economic agents. We believe that the results of this paper can be used as a basis for further research on the capital investment process. For instance, one can view the results of this paper as a subgame equilibrium in a larger game in which a firm chooses among diverse ways to raise capital. In addition, the method used in this paper can be used in analyzing a wide range of problems arising from information asymmetry that the Korean financial market faces.

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The Antimicrobial Characteristics of McSSP-31 Purified from the Hemocyte of the Hard-shelled Mussel, Mytilus coruscus (참담치(Mytilus coruscus) 혈구(hemocyte)에서 분리한 McSSP-31의 항균 특성 분석)

  • Oh, Ryunkyoung;Lee, Min Jeong;Kim, Young-Ok;Nam, Bo-Hye;Kong, Hee Jeong;Kim, Joo-Won;Park, Jung-Youn;Seo, Jung-Kil;Kim, Dong-Gyun
    • Journal of Life Science
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    • v.27 no.11
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    • pp.1276-1289
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    • 2017
  • This study isolated and purified the antimicrobial peptide McSSP-31 from an acidified hemocyte extract of a Mytilus coruscus. The antimicrobial peptide was purified by using a $C_{18}$ reversed-phase high-performance liquid chromatography (HPLC). The peptide was determined to be 3330.549 Da by matrix assisted-laser desorption ionization time-of-flight mass spectrophotometer (MALDI-TOF/MS). The N-terminus of a 14 amino-acid sequence was identified as P-S-P-T-R-R-S-T-S-R-S-K-S-R by Edman degradation method. The acquired sequence showed a 93% similarity with the sperm-specific protein Phi-1, which is from M. californianus. The identified open-reading frame (ORF) of peptide was 306 bp encoding 101 amino acids, which was analyzed by rapid amplification of cDNA ends (RACE), cloning and sequencing analysis. We compared the full sequence with other known proteins that reveal the sperm-specific protein Phi-1 (93.5%) of M. californianus. Synthesized antimicrobial peptide (McSSP-31) showed antibacterial activity against gram-positive bacteria including B. subtilis, S. mutans, S. aureus and gram-negative bacteria including E. coli, K. pneumoniae, P. mirabilis, P. aeruginosa and fungi, C. albicans. Also, synthesized peptide showed strong antibacterial activity against antibiotic-resistant strains, including S. aureus. The cytotoxicity of the peptide was determined by using the HUVEC human cell line. The peptide did not exhibit any significant cytotoxic effects on the normal human cell line, and it had very low hemolytic activity with flounder hemoglobin. The results demonstrated that peptide purified from the hemocyte of a M. coruscus exhibits antibacterial activity against various bacteria and has the potential to be an alternative antibiotic agent.

Immunogenicity of Synthetic Peptide Specific for Major Immunogenic Determinat of Hepatitis B Surface Antigen (B형간염(型肝炎) 표면항원(表面抗原)의 주면역원(主免疫原) 결정기(決定基)에 특이(特異)한 합성(合成) Peptide의 면역원성(免疫原性)에 관한 연구(硏究))

  • Shin, Kwang-soon;Han, Su-nam
    • Korean Journal of Veterinary Research
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    • v.25 no.1
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    • pp.7-17
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    • 1985
  • Many investigators have been pursuing various attempts so far to produce hepatitis B surface antigen(HBsAg) vaccines using the techniques such as isolation from plasma of chronic HBsAg carrier, recombinant DNA technique or preparation of synthetic peptides specific for immunogenic determinants. Hepatitis B virus can not grow on any cell lines by the tissue culture technique at the present time. The plasma of chronic HBsAg carrier is expensive and its source is limited. The HBsAg from the recombinant DNA technique gave still very low yield. Another approach, therefore, has been initiated to develop a synthetic hepatitis B virus vaccine. The possible use of several distinct synthetic vaccines in prophylaxis can be facilitated by availability of full synthetic immunogens. Peptides synthesized for potential application as antiviral vaccines have been mostly tested in the form of conjugates with carrier proteins, although the free synthetic peptide can be immunogenic. To understand basic knowledges on the antigenicity and immunogenicity of a synthetic peptide specific for major immunogenic determinant of HBsAg, a nonapeptide, $H_2N^{139}Cys-Thr-Lys-Pro-Thr-Asp-Gly-^{146}Asn-Aba$ COOH, which corresponds to HBsAg amino acid residues 139 to 147, was synthesized by the Merrifield's solid-phase method with a slight modification. The antigenicity and immunogenicity of this specific synthetic peptide were examined comparing with purified plasma-derived natural HBsAg. The results obtained are as follows; 1. The peptide synthesized showed the identical amino acid composition to the theoretical value. The degree of purification and molecular weight were acertained by methods of high performance liquid chromatography and mass spectrometry. 2. Using m-maleimidobenzoyl-N-hydroxysuccinimide ester as a conjugating agent, the synthetic peptide was conjugated to rabbit albumin and ${\gamma}$-globulin, tetanus and diphtheria toxoids, and keyhole limpet hemocyanin. Their conjugation yields were 8.3, 9.5, 15.8, 13.5, and 11.2%, respectively. 3. The natural HBsAg was purified from plasma of chronic HBsAg carrier. By the electron microscopic observation of the purified natural HBsAg preparation, no Dane particles were observed and the preparation showed negative DNA polymerase activity. 4. Antigenicity of the synthetic peptide and the plasma-derived natural HBsAg was determined by competition radioimmunoassay using $^{125}I$-natural HBsAg. Their 50% inhibitions appeared as $90{\mu}g/ml$ and $0.12{\mu}g/ml$ for the synthetic peptide and the natural HBsAg, respectively. This indicates that the former was about 750-fold less antigenic than the latter. 5. Immunogenicity of the synthetic peptide was determined by administering the peptide-carrier conjugates into rabbits with and without Freund's complete adjuvant. Regardless the carrier proteins and adjuvant, positive immune responses to the synthetic peptide were observed. The higher antibody titers, however, were shown in the groups administered with Freund's complete adjuvant. 6. Immunizing dose 50% in mice of the various peptide-carrier conjugates was 5.47, 6.00, 65.16, 31.25 and $13.03{\mu}g/dose$ for rabbit albumin and ${\gamma}$-globulin, tetanus and diphtheria toxoids, and keyhole limpet hemocyanin, respectively, while the natural HBsAg showed $0.65{\mu}g/dose$. 7. It was postulated that homologous proteins prefer to heterologous ones as the carriers.

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Improvements in the Environmental Impact Assessment on Seawater and Sediment Qualities for Coastal Dredging Projects (연안준설 사업에 따른 해양 수질 및 퇴적물 영향평가 개선 방안)

  • Kim, Yeong-Tae;Kim, Gui-Young;Jeon, Kyeong-Am;Lee, Dae-In;Yu, Jun;Kim, Hee-Jung;Kim, In-Chul;Eom, Ki-Hyuk
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.19 no.2
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    • pp.119-128
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    • 2013
  • Since the early 2000s, demand for coastal dredging projects have been significantly increased, and the dredged sediments have showed the continuing marked increases through the multiple projects with other coastal development and constructions. As significant or potential degradation of marine environment has been mounting, we checked the current situation of marine environmental impact assessment through marine water and sediment qualities in relation with dredging projects of the sea area utilization consultation statements submitted in 2011. While analysis percentages of the general items were usually higher, harmful components such as metals revealed wide variation of analysis percentages. In the event of analysis of metals, the pre-treatment process (full digestion) and analysis method were not properly implemented in accordance with the guidelines for preparation of consultation statements. Although not specified in the guidelines, verification procedures (tests of recovery efficiency and detection limit) to secure the reliability were almost ignored. As a result, most of developers did conduct poor marine environmental impact assessment on coastal dredging and related projects. We suggested that the responsible government authority should establish new detailed guidelines on the sea area utilization consultation for more strict evaluation and diagnosis of marine environment and distinctly request the developer to obey the guidelines by complementing the system of the sea area utilization consultation.

Seismic wave propagation through surface basalts - implications for coal seismic surveys (지표 현무암을 통해 전파하는 탄성파의 거동 - 석탄 탄성파탐사에 적용)

  • Sun, Weijia;Zhou, Binzhong;Hatherly, Peter;Fu, Li-Yun
    • Geophysics and Geophysical Exploration
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    • v.13 no.1
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    • pp.1-8
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    • 2010
  • Seismic reflection surveying is one of the most widely used and effective techniques for coal seam structure delineation and risk mitigation for underground longwall mining. However, the ability of the method can be compromised by the presence of volcanic cover. This problem arises within parts of the Bowen and Sydney Basins of Australia and seismic surveying can be unsuccessful. As a consequence, such areas are less attractive for coal mining. Techniques to improve the success of seismic surveying over basalt flows are needed. In this paper, we use elastic wave-equation-based forward modelling techniques to investigate the effects and characteristics of seismic wave propagation under different settings involving changes in basalt properties, its thickness, lateral extent, relative position to the shot position and various forms of inhomogeneity. The modelling results suggests that: 1) basalts with high impedance contrasts and multiple flows generate strong multiples and weak reflectors; 2) thin basalts have less effect than thick basalts; 3) partial basalt cover has less effect than full basalt cover; 4) low frequency seismic waves (especially at large offsets) have better penetration through the basalt than high frequency waves; and 5) the deeper the coal seams are below basalts of limited extent, the less influence the basalts will have on the wave propagation. In addition to providing insights into the issues that arise when seismic surveying under basalts, these observations suggest that careful management of seismic noise and the acquisition of long-offset seismic data with low-frequency geophones have the potential to improve the seismic results.