• Title/Summary/Keyword: Focal mechanism

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Neotectonic Crustal Deformation and Current Stress Field in the Korean Peninsula and Their Tectonic Implications: A Review (한반도 신기 지각변형과 현생 응력장 그리고 지구조적 의미: 논평)

  • Kim, Min-Cheol;Jung, Soohwan;Yoon, Sangwon;Jeong, Rae-Yoon;Song, Cheol Woo;Son, Moon
    • The Journal of the Petrological Society of Korea
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    • v.25 no.3
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    • pp.169-193
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    • 2016
  • In order to characterize the Neotectonic crustal deformation and current stress field in and around the Korean Peninsula and to interpret their tectonic implications, this paper synthetically analyzes the previous Quaternary fault and focal mechanism solution data and recent geotechnical in-situ stress data and examines the characteristics of crustal deformations and tectonic settings in and around East Asia after the Miocene. Most of the Quaternary fault outcrops in SE Korea occur along major inherited fault zones and show a NS-striking top-to-the-west thrust geometry, indicating that the faults were produced by local reactivation of appropriately oriented preexisting weaknesses under EW-trending pure compressional stress field. The focal mechanism solutions in and around the Korean Peninsula disclose that strike-slip faulting containing some reverse-slip component and reverse-slip faulting are significantly dominant on land and in sea area, respectively. The P-axes are horizontally clustered in ENE-WSW direction, whereas the T-axes are girdle-distributed in NNW direction. The geotechnical in-situ stress data in South Korea also indicate the ENE-trending maximum horizontal stress. The current crustal deformation in the Korean Peninsula is thus characterized by crustal contraction under regional ENE-WSW or E-W compression stress field. Based on the regional stress trajectories in and around East Asia, the current stress regime is interpreted to have resulted from the cooperation of westward shallow subduction of the Pacific Plate and collision of Indian and Eurasian continents, whereas the Philippine Sea plate have not a decisive effect on the stress-regime in the Korean Peninsula due to its high-angle subduction that resulted in dominant crust extension of the back-arc region. It is also interpreted that the Neotectonic crustal deformation and present-day tectonic setting of East Asia commenced with the change of the Pacific Plate motion during 5~3.2 Ma.

An Analysis of the Fault Plane Solution and Intensity on the Iksan Earthquake of 22 December 2015 (2015년 12월 22일 발생한 익산지진의 단층면해와 진도 분석)

  • Kim, Jin-Mi;Kyung, Jai Bok;Kim, Kwang-Hee
    • Journal of the Korean earth science society
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    • v.38 no.7
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    • pp.561-569
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    • 2017
  • Fault plane solutions of the Iksan earthquake ($M_L=3.85$) and two aftershocks were obtained using the FOCMEC (FOCal MEChanism determination) program. The main event showed the characteristic of strike slip faulting with reverse component. It has the fault planes with NE-SW or NW-SE direction. This is similar to the fault characteristics of earthquake pattern in the inland area of the Korean Peninsula. In order to detect micro-earthquake events, continuous seismic waveform data of the thirteen seismic stations within a radius of 100km from epicenter were analyzed by PQLII program (PASSCAL, 2017) for the period from December 15, 2015 to January 22, 2016. The epicenters of nineteen micro-events were newly determined by Hypoinverse-2000 program. They are not concentrated along some lineaments or fault lines. The intensity of the Iksan earthquake was obtained by estimating the telephone inquiries, the degree of ground shaking or damage all around the southern peninsula. The instrumental intensity was also obtained using PGA (Peak Ground Acceleration) records. As a result, the maximum MM intensity was estimated to be V near the epicenter.

The Prediction Model of Adaptation in Patients with Rheumatoid Arthritis - Propositional Synthesis of Roy's and Lazarus & Folkman's Theory - (류마티스 관절염 환자의 적응 예측모형 -Roy이론과 Lazarus 및 Folkman 이론의 명제 합성-)

  • Kim, In-Ja;Suh, Moon-Ja
    • Journal of muscle and joint health
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    • v.4 no.2
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    • pp.197-220
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    • 1997
  • The lack of a comprehensive theory describing the mechanism of adaptation scientifically has been one of the limiting factors for the development of nursing intervention of patients with chronic illness. Since Roy's theory provides the general conceptual framework depicting adaptation process with structural stimuli and control mechanism, it is appropriate to understand the process of adaptation. But in Roy's theory, the propositions about cognator and regulator as control mechanisms are not clearly defined. For this reason, most of the previous researches applying the Roy's theory have disregarded the study of cognator and regulator. For the patients with chronic illness such as rheumatoid arthritis, it was reported that adaptation states were different for the same stimuli due to the difference of the control mechanism. Moreover in nursing it is important to identify the control mechanism which can be and must be intervened by nurses. It was the Lazarus and Folkman's theory that proposed the control mechanism. They suggested that individual differences in the reaction against the perceived stress are due to the difference in appraisal and coping. Therefore, the synthesis of Roy's and Lazarus and Folkman's propositions might help to clearly understand the mechanism of adaptation. From this point, a theoretical framework has been developed and tested. The subjects were the 297 patients who had been diagnosed rheumatoid arthritis and attended the outpatient clinic. A hypothetical prediction model of adaptation was tested by the covariance structure analysis with PC-LISREL 7.13. As a result, the overall fit was good($x^2$=78.83, p=0.00 ; GFI=0.96 : AGFI=0.90 ; RMR=0.04) for the hypothetical model. In the final model added GA(5, 1), the overall fit was increased ($x^2$=57.82, p=0.003 ; GFI=0.97 ; AGFI=0.93 : RMR=0.036). Except the fact that illness symptoms affected physical adaptation directly, it was supported that focal and contextual stimuli affected physical and psychosocial adaptation through appraisal and coping. Therefore, it was asserted that the synthesis of two theory's propositions was appropriate. So this model would be useful for the theoretical framework in the nursing practice. And this study synthesizing and testing the theory might contribute to establish nursing's scientific base.

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The Effects of Perpendicular Needling Laogong ($PC_8$) on the Improvement of Cerebral Hemodynamics in Rats (노궁(勞宮)($PC_8$) 직자(直刺)가 백서(白鼠)의 뇌혈류력학(腦血流力學)에 미치는 영향)

  • Heo, Jin;Kim, Jung-Ho;Kim, Young-Il
    • Journal of Acupuncture Research
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    • v.28 no.4
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    • pp.19-35
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    • 2011
  • Objectives : This study was designed to investigate the effects of acupuncturing $PC_8$ used perpendicular needling method determine the mechanism of action of acupuncturing $PC_8$ by measuring the changes of regional cerebral blood flow (rCBF) and mean arterial blood pressure (MABP) in normal rats. Methods : This study also investigated the effects of acupuncturing $PC_8$ on the change of rCBF in cerebral ischemic rats, and revealed the mechanism of its action. In addition, the effects of acupuncturing $PC_8$ on focal ischemic brain injury was studied in cerebral ischemic rats. Results : 1. Acupuncturing $PC_8$ significantly increase rCBF but decreased MABP in normal rats. 2. Acupuncturing $PC_8$ increased of rCBF was significantly inhibited by pretreatment with indomethacin (1mg/kg, i.p.), an inhibitor of cyclooxygenase in normal rats. 3. Acupuncturing $PC_8$ increased of rCBF was significantly inhibited by pretreatment methylene blue (10 ${\mu}g$/kg, i.p.), an inhibitor of guanylate cyclase in normal rats. 4. Acupuncturing $PC_8$ was significantly improved the rCBF than control group increased unstable in cerebral ischemic rats. 5. Acupuncturing $PC_8$ was not significantly improved the rCBF than control group by pretreatment with indomethacin (1mg/kg, i.p.), an inhibitor of cyclooxygenase in cerebral ischemic rats. 6. Acupuncturing $PC_8$ was significantly increased the rCBF than control group by pretreatment methylene blue ($10{\mu}g$/kg, i.p.), an inhibitor of guanylate cyclase in cerebral ischemic rats. Conclusions : In conclusion, our study suggested that acupuncturing $PC_8$ can increase rCBF in normal state, and improve stability of rCBF in ischemic state. In addition, we suggested that mechanisms related with acupuncturing $PC_8$ was involved in the guanylate cyclase pathway.

Development of fragility curves for RC bridges subjected to reverse and strike-slip seismic sources

  • Mosleh, Araliya;Razzaghi, Mehran S.;Jara, Jose;Varum, Humberto
    • Earthquakes and Structures
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    • v.11 no.3
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    • pp.517-538
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    • 2016
  • This paper presents a probabilistic fragility analysis for two groups of bridges: simply supported and integral bridges. Comparisons are based on the seismic fragility of the bridges subjected to accelerograms of two seismic sources. Three-dimensional finite-element models of the bridges were created for each set of bridge samples, considering the nonlinear behaviour of critical bridge components. When the seismic hazard in the site is controlled by a few seismic sources, it is important to quantify separately the contribution of each fault to the structure vulnerability. In this study, seismic records come from earthquakes that originated in strike-slip and reverse faulting mechanisms. The influence of the earthquake mechanism on the seismic vulnerability of the bridges was analysed by considering the displacement ductility of the piers. An in-depth parametric study was conducted to evaluate the sensitivity of the bridges' seismic responses to variations of structural parameters. The analysis showed that uncertainties related to the presence of lap splices in columns and superstructure type in terms of integral or simply supported spans should be considered in the fragility analysis of the bridge system. Finally, the fragility curves determine the conditional probabilities that a specific structural demand will reach or exceed the structural capacity by considering peak ground acceleration (PGA) and acceleration spectrum intensity (ASI). The results also show that the simply supported bridges perform consistently better from a seismic perspective than integral bridges and focal mechanism of the earthquakes plays an important role in the seismic fragility analysis of highway bridges.

A case of pyomyositis due to Mycobacterium tuberculosis (17개월 여아에서 발견된 근육내 결핵 1례)

  • Bae, Yun-Jin;Choi, Jin-Sung;Lee, Young Ah;Kim, Sung-Soo;Rha, Seo-Hee;Jung, Jin-A
    • Clinical and Experimental Pediatrics
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    • v.49 no.10
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    • pp.1116-1119
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    • 2006
  • Pyomyositis is a primary bacterial infection of the skeletal muscles. Although infection can affect any skeletal muscle, the large muscle groups such as the quadriceps or gluteal muscles are most often the focus of this disease, and most commonly the inflammation is focal, involving a single muscle. The mechanism of pyomyositis is poorly understood. The local mechanical trauma at the time of an incidental bacteremia is frequently postulated as a mechanism that could explain the high incidence of the disease in tropical areas and its male preponderance. Staphylococcus aureus is the most common organism responsible for pyomyositis. Mycobacterium tuberculosis primarily affects the lungs, and the prevalence of active pulmonary tuberculosis co-existing with musculoskeletal tuberculosis has been about 30 percent. We report here on a case of an otherwise healthy 17-month-old girl, who had tuberculous pyomyositis at the upper arm after the hepatitis A vaccination with no evidence of any coexistent active tuberculosis.

Analysis of Polishing Mechanism and Characteristics of Aspherical Lens with MR Polishing (MR Polishing을 이용한 비구면 렌즈의 연마 메커니즘 및 연마 특성 분석)

  • Lee, Jung-Won;Cho, Myeong-Woo;Ha, Seok-Jae;Hong, Kwang-Pyo;Cho, Yong-Kyu;Lee, In-Cheol;Kim, Byung-Min
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.14 no.3
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    • pp.36-42
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    • 2015
  • The aspherical lens was designed to be able to array a focal point. For this reason, it has very curved surface. The aspherical lens is fabricated by injection molding or diamond turning machine. With the aspherical lens, tool marks and surface roughness affect the optical characteristics, such as transmissivity. However, it is difficult to polish free form surface shapes uniformly with conventional methods. Therefore, in this paper, the ultra-precision polishing method with MR fluid was used to polish an aspherical lens with 4-axis position control systems. A Tool path and polishing mechanism were developed to polish the aspherical lens shape. An MR polishing experiment was performed using a generated tool path with a PMMA aspherical lens after the turning process. As a result, surface roughness was improved from $R_a=40.99nm$, $R_{max}=357.1nm$ to $R_a=4.54nm$, $R_{max}=35.72nm$. Finally, the MR polishing system can be applied to the finishing process of fabrication of the aspherical lens.

Discount Presentation Framing & Bundle Evaluation: The Effects of Consumption Benefit and Perceived Uncertainty of Quality (묶음제품 가격 할인 제시 프레이밍 효과: 지각된 소비 혜택과 품질 불확실성의 영향을 중심으로)

  • Im, Meeja
    • Asia Marketing Journal
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    • v.14 no.1
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    • pp.53-81
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    • 2012
  • Constructing attractive bundle offers depends on more than an understanding of the distribution of consumer preferences. Consumers are also sensitive to the framing of price information in a bundle offer. In classical economic theory, consumers' utility should not change as long as the total price paid stays same. However, even when total prices are identical, consumers' preferences toward a bundle product could be different depending on the format of price presentation and the locus of price discount. A weighted additive model predicts that the impact of a price discount on the overall evaluation of the bundle will be greater when the discount is assigned to the more important product in the bundle(Yadav 1995). Meanwhile, a reference dependent model asserts that it is better to assign a price discount to a tie-in component that has a negative valuation at its current offer price than to a focal product that has a positive valuation at its current offer price(Janiszewski and Cunha 2004). This paper has expanded previous research regarding price discount presentation format, investigating the reasons for mixed results of prior research and presenting new mechanisms for price discount framing effect. Prior research has hypothesized that bundling is used to sell a tie-in component with an offer price above the consumer's reference price plus a focal product of the same offer price with reference price(e.g., Janiszewski and Cunha 2004). However, this study suggests that bundling strategy can be used for increasing product's attractiveness through the synergy between components even when offer prices of bundle components are the same with reference prices. In this context, this study employed various realistic bundle sets with same price between offer price and reference price in the experiment. Hamilton and Srivastava(2008) demonstrated that when evaluating different partitions of the same total price, consumers prefer partitions in which the price of the high-benefit component is higher. This study determined that their mechanism can be applied to price discount presentation formats. This study hypothesized that price discount framing effect depends not on the negative perception of tie-in component with offer price above reference price but rather on the consumers' perceived consumption benefit in bundle product. This research also hypothesized that preference for low-benefit discount mechanism is that perceived consumption benefit reduces price sensitivity. Furthermore, this study investigated how consumers' concern for quality in a price discount--a factor not considered in previous research--influences price discount framing. Yadav(1995)'s experiment used only one magazine bundle of relatively low quality uncertainty and could not show the influence of perceived uncertainty of quality. This study assumed that as perceived uncertainty of quality increases, the price sensitivity mechanism for assigning the discount to low-benefit will increase. Further, this research investigated the moderating effect of uncertainty of quality in price discount framing. The results of the experiment showed that when evaluating different partitions of the same total price and the same amount of discounts, the partition that discounts in the price of low benefit component is preferred to the partition that decreases the price of high benefit component. This implies that price discount framing effect depends on the perceived consumption benefit. The results also demonstrated that consumers are more price sensitive to low benefit component and less price sensitive to high benefit component. Furthermore, the results showed that the influence of price discount presentation format on the evaluation of bundle product varies with the perceived uncertainty of quality in high consumption benefit. As perceived uncertainty of quality gradually increases, the preference for discounts in the price of low consumption benefit decreases. Besides, the results demonstrate that as perceived uncertainty of quality gradually increases, the effect of price sensitivity in consumption benefit also increases. This paper integrated prior research by using a new mechanism of perceived consumption benefit and moderating effect of perceived quality uncertainty, thus providing a clearer explanation for price discount framing effect.

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Some Characteristics of Seismicity and Stress State in the Korean Peninsula Using the Korean Seismic Data of the Past and the Present (과거 및 현재 지진 Data로부터 한반도 지진활동과 응력 상태)

  • 오충량;김소구;고복춘
    • The Journal of Engineering Geology
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    • v.5 no.3
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    • pp.309-329
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    • 1995
  • Seismicity and stress state in the Korean peninsula are studied using the catalogue of historical earthquakes and that from the seismological observations before the 1960s, with the aid of instrumental catalogue up to 1995. It seems that the completeness of the historical catalogue has a significant enhancement during the first two hundred years of the Yi dynasty, i.e., from the 1400s to the 1600s. From then on the catalogue may be regarded as near to complete for strong earthquakes in an overall sense. From the distribution of strong earthquakes, three seismic zones may be identified. From the south to the north, those are the southern seismic zone (남부지진대), the Seoul-Pyongyang seismic zone (서울-평양지진대), and the northern seismic zone (북부지진대). The mechanisms of some earthquakes obtained using first motion read- ings are reevaluated with a grid testing method. The results indicate that the compressional axis is nearly horizontal along the EW direction.

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Temporal and Spatial Variations of the ML 5.8 Gyeongju Earthquake on September 12, 2016

  • Lee, Gyeong Su;Kyung, Jai Bok;Lee, Sang Jun
    • Journal of the Korean earth science society
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    • v.39 no.4
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    • pp.342-348
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    • 2018
  • An earthquake of $M_L$ 5.8 hit the Gyeongju area on September 12, 2016. A sequence of foreshock-mainshock-aftershock of 588 events with equal to or greater than magnitude 1.5 occurred for six months in this area. Around ninety-nine percentage (98.8%) of the total energy was released intensively within a day, and about 80% of the total events took place within a month after the Gyeongju earthquake. The epicentral distribution of aftershocks of major events ($M_L$ 5.1, 5.8, 4.5, and 3.5) were elongated in the direction of $N30^{\circ}E$. They correlate well with the focal mechanism solution. These facts support the inference that the Gyeongju earthquakes occurred on a sub-parallel subsidiary fault of the Yangsan fault zone or on the linking damage zones between Deokcheon and Yangsan fault. During the last six years before the Gyeongju earthquake, there were few events within 10-km radius from the epicenter. This seismic gap area was filled with a sequence of the Gyeongju earthquakes. The b value for aftershock of the Gyeongju earthquakes is 1.09.