• Title/Summary/Keyword: Wall Pressure

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A Study on the Structural Deformations in the Sedimentary Layer Resulted from Magma Intrusion (마그마관입에 의한 상부퇴적층의 변형에 관한연구)

  • Min, Kyung Duck;Kim, Won Young
    • Economic and Environmental Geology
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    • v.10 no.1
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    • pp.37-48
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    • 1977
  • The earth's crust is unceasingly undergoing deformations because of the forces acting upon it. The relationship between the tectonic forces and the resulting deformations are found from the states of stresses in the earth's crust induced by these forces. The study has been attempted to analyze the deformations of the overlying sedimentary layers, which are deformed by the magma intrusion along its lower boundary. The elastic model is constructed to analyze the geologic structures, by means of the theory of elasticity, and then the appropriate boundary conditions are given. The solution of the Airy stress function which satisfies the given boundary conditions is derived from the analytic method. The internal stress distributions of the deformed elastic model layer are portrayed by principal stress trajetories, and then the corresponding potential faults and joints systems are predicted from the Coulomb-Mohr failure criterion. The internal displacement distributions are shown by the calculated displacement components vectors, namely horizontal, vertical and net components. Results of the numerical calculations show the developments of some geologic structures as follows; (1) one set of shear joints and or two sets of shear joints which are oppisite directions, and one set of extension joints parallel to the ${\sigma}_1$ direction, (2) one set of high angle thrusts and normal faults, (3) symmetric fold; both limbs are dipping in opposite direction with low angle. The field work at the Wall-A San area, located near Jinju City, in southern Korea, had accomplished to compare the field structures with the predicted ones. The results of the comparison exhibits the developments of joint and fault systems satisfactorily consistent with each others. But the area does not show any type of folding, in spite of the intrusion of a granodiorite massif, this fact is one of the important features of the whole Kyungsang sedimentary basins of Mesozoic age distributed at the south-eastern parts of Korea. For this reason, it is thought that the magma intrusion had occurred with extremly low pressure. The geologic structures have been modified by the erosion and weathering throughout the geologic time, and the conditions of the sedimentary layers (width, thickness and radius of magma) are not the same as before, being intruded by the magma. To enlighten this, it is preferable to study these geologic structures with analyses of various types of rheological models.

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PCR-SSCP of Serum Lysozyme Gene (Exon-III) in Riverine Buffalo and Its Association with Lysozyme Activity and Somatic Cell Count

  • Sahoo, Nihar Ranjan;Kumar, Pushpendra;Bhushan, Bharat;Bhattacharya, T.K.;Sharma, Arjava;Dayal, Sanker;Pankaj, Prabhat Kumar;Sahoo, Monalisa
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.8
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    • pp.993-999
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    • 2010
  • Serum lysozyme gene is one of the important genes influencing the immune system as its product can cause lysis of bacterial cell wall by cleaving the peptidoglycan layer. The present investigation on the serum lysozyme gene of Indian riverine buffalo was undertaken with the objectives to identify and characterize single nucleotide polymorphic patterns by PCR-SSCP method as well as to study the effect of different genotypes on serum lysozyme activity and somatic cell count. A total of 280 animals comprising four different famous bubaline breeds (Murrah, Mehsana, Surti and Bhadawari), spread over six different farms across the country were used for this study. A 276 bp (partial intron 2, complete exon 3 and partial intron 3) fragment of lysozyme gene was screened for polymorphism using the SSCP technique. Four genotypes namely AA, AB, BC and AC were observed, out of which BC genotype was found to be the most frequent. Among these three alleles, C allele (0.38) was most prevalent in these populations. Various SSCP allelic variants were cloned for sequencing and sequences were submitted to NCBI Genbank. From the alignment of the nucleotide sequences of various allelic variants, it was found that there were differences in 12 positions among the alleles, out of which maximum variation (at 8 places) was found in the intronic region. The allele A was closer to allele-C than allele-B. Allele B was phylogenetically equidistant from both of the other alleles. Mean lysozyme activity determined in serum samples of different animals of Murrah buffalo was $27.35{\pm}2.42\;{\mu}g$ per ml of serum, whereas the mean somatic cell count was $1.25{\pm}0.13{\times}10^5$ cells per ml of milk. The SSCP pattern-wise effects of various genotypes on lysozyme activity and SCC were analyzed. Although the mean values were apparently different in various genotypes, these differences were statistically non-significant. It can be concluded that the riverine buffaloes are sufficiently polymorphic with respect to serum lysozyme gene. The absence of AA genotype in Bhadawari breed of buffalo can be considered as a marker for breed characterization. The difference of four nucleotides in exon-3 indicates high selection pressure on the gene.

A Study on Separation Control by Local Suction in Front of a Hemisphere in Laminar Flow (층류경계층 내 반구 전방의 국부적인 흡입에 의한 표면 박리 제어)

  • Kang, Yong-Duck;An, Nam-Hyun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.24 no.1
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    • pp.92-100
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    • 2018
  • Vortical systems are considered a main feature to sustain turbulence in a boundary layer through interaction. Such turbulent structures result in frictional drag and erosion or vibration in engineering applications. Research for controlling turbulent flow has been actively carried out, but in order to show the effect of vortices in a turbulent boundary layer, it is necessary to clarify the mechanism by which turbulent energy is transferred. For this purpose, it is convenient to demonstrate and capture phenomena in a laminar boundary layer. Therefore, in this study, the interactions of disturbed flow around a hemisphere on a flat plate in laminar flow were analyzed. In other words, a street of hairpin vortices was generated following a wake region formed after flow separation occurred over a hemisphere. Necklace vortices surrounding the hemisphere also appeared due to a strong adverse pressure gradient that brought high momentum fluid into the wake region thereby leading to an increase in the frequency of hairpin vortices. To mitigate the effect of these necklace vortices, local suction control was applied through a hole in front of the hemisphere. Flow visualization was recorded to qualitatively determine flow modifications, and hot-film measurements quantitatively supported conclusions on how much the power of the hairpin vortices was reduced by local wall suction.

Generation of blast load time series under tunnelling (터널 굴착 발파하중 시간이력 생성)

  • Ahn, Jae-Kwang;Park, Duhee;Shin, Young-Wan;Park, Inn-Joon
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.16 no.1
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    • pp.51-61
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    • 2014
  • It is necessary to perform a dynamic analysis to numerically evaluate the effect of blasting on nearby facilities. The blast load time history, which cannot be directly measured, is most often determined from empirical equation. The load has to be adjusted to account for various factors influencing the load and the frequency, but there is not a clear guideline on how to adjust the load. In this study, a series of 2D dynamic numerical analyses that simulates a closely monitored test blasting is performed, from which the blast load that matches the measured vibrations are derived. In the analyses, it is assumed that the hole generated by the blasting is in the form of a circle, and the load was applied normally to the wall of the opening. Special attention was given in selecting the damping ratio for the ground, since it has important influence on the wave propagation and attenuation characteristics of the blast induce waves. The damping ratio was selected such that it matches favorably with the attenuation curve of the measurement. The analyses demonstrate that the empirical blast load widely used in practice highly overstimates the vibration since it does not account for the energy loss due to rock fragmentation. If the empirical load is used without proper adjustment, the numerical analysis may seriously overstimate the predicted vibration, and thus has to be reduced in the analysis.

Study on the Realities in Seoul Subway Crimes: Criminal Psychology (서울지하철 범죄 실태에 대한 범죄심리학적 연구)

  • Rim, Sang-Gon
    • Korean Security Journal
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    • no.7
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    • pp.233-285
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    • 2004
  • ‘Defined legally as a violation of law' (Sutherland, E. H. Principles of Criminology, Lippincott, Chicago, 1939) Crime within the group is essentially and primarily antisocial in that the criminal who is welfare of his group acts instead against it and breaks the principles of social solidarity not merely by not doing what these principles prescribe, but by doing something exactly opposites. Any program set up to attack crime and delinquent behavior at their sources. A program of his nature needs the constant and comprehensive collaboration of psychiatrists, social works, educations, lawmakers, and public officials, since crime is a social problem and it should be treated as such. Some crime preventives which should be mentioned are as follows, (1) The insurance that every child will be decently born and that his home life be socially and economically adequate; without socially mature parents the chid is handicapped at the start; thus parental education, integrated with the public school system, should be developed now. (2) A more meaningful educational program which would emphasize ideals of citizenship, moral integrity, and respect for the law and the police. (3) A periodic check made for potential delinquents throughout the public schools and treatment provided if possible; and if not, proper segregation in institutions. (4) Careful attention paid to press, movies, and radio so that crime may no longer appear to be glamorous. This can be done by women's clubs, civic bodies, and other educational groups exerting pressure on the movie syndicates and broadcasting companies to free their productions of the tawdry and lurid characteristics of crime and criminals. Aggression associated with the phallic stage of development, The child ordinarily comprehends sexual intercourse as an aggressive and sadistic act on the part of the male, and specifically on the part of the penis. Evidence that the penis is phantasied as a weapon of violence and destruction come from unconscious productions of normal adults. Limerick, for instance, often refer to the penis as square, or too large, etc., so that intercourse is dangerous and painful for the partner, This may wall be a projection of the male's own fear of coitus. A certain portion of the death-instinct always remains within the person; it is called 'primal sadism' and according to Freud is identical with masochism. 'After the chief part of it(the death instinct) has been directed outwards towards objects, there remains as a residuum within the organism the true erotogenic masochism, which on the one hand becomes a component of the libido and on the other still has the subject itself for a object.' Criminalism, compulsive-neurotic frequent repetition of criminal acts in a compulsive manner. Like most symptoms of the compulsive-neurotic, such antisocial act are closely rated to feelings of hostility and aggression, often against the father. Because these acts are symptomatic, they afford only temporary relief and are therefore repeated. One patient with compulsive-neurotic criminalism was apprehended after breaking into hardware store and stealing money. He later confessed to many similar incidents over the preceding two years. At the same time it was apparent that he stole only for the sake of stealing. He did not need the money he thus obtained and had no special plans for using it.

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Compositional Effect on the Magnetic Properties of Nd-Fe-Co-B and Nd-Fe-Co-Zr-B Bonded Magent (합금조성에 따른 Nd-Fe-Co-B 및 Nd-Fe-Co-Zr-B계 본드자석의 자기특성)

  • 최승덕;이우영;양충진
    • Journal of the Korean Magnetics Society
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    • v.1 no.2
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    • pp.60-68
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    • 1991
  • In compacting the melt-spun $Nd_{14}Fe_{76}Co_{4}B_{6}$ and $Nd_{10.5}Fe_{79}Co_{2}Zr_{15}B_{7}$ magnetic powders. the difference in composition induces a different behavior of closed packing rate as a function of aspect ratio of the powders. The $Nd_{10.5}Fe_{79}Co_{2}Zr_{1.5}B_{7}$ alloy having a low Co/Fe ratio (low density) shows the better green density to have an enhanced closed packing rate. An empirical power equation relating the green density with the compacting pressure was obtained such as ${\phi}(g/cm^{2})=5.2~5.6{\times}P^{0.045~0.065}(ton/cm^{2})$. The $Nd_{14}Fe_{76}Co_{4}B_{6}$ alloy having a high Nd/Fe ratio possesses much finer grain size(50~60 nm) than that of $Nd_{10.5}Fe_{79}Co_{2}Zr_{1.5}B_{7}$ alloy and shows the higher coercivity($iH_{c}=14~15kOe$). The higher Nd/Fe ratio in the melt-spun Nd-Fe-Co-B alloy, where the domain wall pinning mechanism was found to be predominant, assists the formation of Nd-rich grain boundary phase acting as a pinning site. The grain boundary ranges over $12~16\;{\AA}$ thick in the Nd-Fe-Co-B alloy while it ranges over $8~12\;{\AA}$ thick in the Nd-Fe-Co-Zr-B alloy.

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Modeling of Extrusion for Pectin Extraction from Apple Pomace (사과박의 펙틴 추출을 위한 압출 공정 모형화)

  • Cho, Yong-Jin;Kim, Chong-Tai;Kim, Chul-Jin;Hwang, Jae-Kwan
    • Korean Journal of Food Science and Technology
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    • v.31 no.4
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    • pp.1011-1016
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    • 1999
  • This study was performed to search a physical method having high yield and quality and minimum environmental pollution for extraction of pectin from apple pomace. Based on the physical solubilization of plant cell wall under the condition of high temperature, pressure and shearing stress, apple pomace was treated by a corotating intermeshing type twin-screw extruder with the diameter-to-length ratio of 1/20. The specific mechanical energy of extruder was introduced as system parameter for extrusion process modeling and the shaft speed, feed rate and moisture content as process variables. The yield, average molecular weight and galacturonic acid content of water-soluble polysaccharides obtained by extrusion were, respectively, modeled with the linear functions of the system parameter which was of the form as a linear function of process variables. The specific mechanical energy increased with increase of shaft speed and with decrease of feed rate and moisture content. Out of process variables, moisture content had the greatest effect on specific mechanical energy. The yield increased with increase of specific mechanical energy while the average molecular weight and galacturonic acid content increased with its decrease. In aspects of yield and quality of pectin, the results from this study showed the possibility to replace a traditional acidic method with the extrusion treatment of this study.

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Effect of Sampling and Analytical Methods on the Fibrous Materials from the Ground Water (시료 채취 조건 및 검사방법에 따른 지하수내 섬유상 물질 검출 양상에 관한 연구)

  • Kim, Ji-Yong;Kim, Jung Ran;Cheong, Hae-Kwan;Lim, Hyun-Sul;Paik, Nam-Won
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.7 no.2
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    • pp.209-222
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    • 1997
  • Authors surveyed the ground water near the waste disposed from a fiberglass production factory to confirm the presence of glassfiber in the water and to determine the effect of sampling conditions and storage on the recovery of fibrous materials in the ground water. Sample was collected at every 4 hours for 48 hours consecutively. After finishing the 48 hours sample, water sampling was done from each tap after repeated turning on and off the water for 30 seconds at each time. Sample was collected in the two 1.5 liter polyethylene bottle after vigorously shaking the bottle with the same water several times with the flowing tap water. At each paired sample, one bottle was stored stand still at room temperature, and the other sample was filtered immediately after sampling. Water was filtered on the Mixed Cellulose Ester filter with negative pressure. Each sample was divided into upper and lower layer. The other bottle was stored at room temperature standstill for 7 days and filtered in the same fashion as the other pair of sample did. Each MCE filter was divided into 4 pieces and one piece was treated with acetone to make it transparent. Each prepared sample was observed by two researchers under the light and polarizing microscopy, scanning electron microscopy and energy dispersive X-ra microanalysis. Fibers were classified by the morphology and polarizing pattern under the polarizing microscope, and count was done. 1. There was a significant fluctuation in number of the fibers, but there was no specific demonstrable pattern. 2. Non-polarizing fibers frequently disappeared after 7 days's storage. But cluster of fibers were found at the wall of the same container by scratching technique. 3. Polarizing fibers were usually found in between the filter and the manicure pasted area. Possible explanations for this phenomenon will be that either these fibers are very light or have electronic polarity. Hence, these fibers are not able to be attached on the surface of slide glass. 4. Under the scanning electron microscopic examination, the fibers which are not refractive under the light microscopy were identified as glassfiber. Other fibers which is refractive under the polarizing microscopy were identified as magnesium silicate fibers. It is strongly suggested that development of standardized method of sample collection and measurement of fibrous material in the water is needed.

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The Design and Protective Capacity Assessment of the Prefabricated PC Arch Ammo Magazines (아치형 조립식 PC 탄약고 설계 및 방호성능 평가)

  • Park, Jang-Kweon;Lim, Chul-Won;Ryu, Dong-Woo;Son, Ki-Young;Baek, Jong-Hyuk;Park, Young-Jun
    • Journal of the Korea Institute of Building Construction
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    • v.14 no.6
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    • pp.615-621
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    • 2014
  • This study suggests the design and assembly drawing of the prefabricated precast concrete arch ammo magazines using the numerical analysis as well as the explosion verification test. The protective capacity of the proposed magazines is identified with the maximum support rotation angles measured by explosion verification tests according to the U.S. Unified Facility Criteria 3-340-02. Using numerical analysis, it is examined that oval-type members are better than the semi-circle ones in terms of protective capacity. Based on this numerical results, the design and assemble drawing for the prefabricated precast concrete arch ammo magazine are developed. It is identified that the structure constructed by invented design and assembly drawing has enough protective capacity against blast pressure caused by 133.75kg TNT explosion. The detonation point cannot be open due to the military security. In sum, it could be concluded that the ammo magazine proposed in this study has reliable protective capacity with enough redundancy. The redundancy means that there are more economic design approach with reducing the curved wall thickness.

Analysis of Apparent Fracture Toughness of a Thick-Walled Cylinder with an FGM Coating at the Inner Surface Containing a Radial Edge Crack (반경방향의 모서리 균열을 갖고 내면이 경사기능재료(FGM)로 코팅된 두꺼운 실린더의 겉보기 파괴인성해석)

  • Afsar, A.M.;Rasel, S.M.;Song, J.I.
    • Composites Research
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    • v.23 no.2
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    • pp.1-9
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    • 2010
  • This study analyzes the apparent fracture toughness of a thick-walled cylinder with a functionally graded material (FGM) coating at the inner surface of the cylinder. The cylinder is assumed to have a single radial edge crack emanating from its inner surface. The crack surfaces and the inner surface of the cylinder are subjected to an internal pressure. The incompatible eigenstrain developed in the cylinder due to nonuniform coefficient of thermal expansion as a result of cooling from sintering temperature is taken into account. Based on a method of evaluating stress intensity factor introduced in our previous study, an approach is developed to calculate apparent fracture toughness. The approach is demonstrated for a cylinder with a TiC/$Al_{2}O_{3}$ FGM coating and some numerical results of apparent fracture toughness are presented graphically. The effects of material distribution profile, cylinder wall thickness, application temperature, and coating thickness on the apparent fracture toughness are investigated in details. It is found that all of these factors play an important role in controlling the apparent fracture toughness of the cylinder.