• Title/Summary/Keyword: bearing system

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Derivation and verification of electrical resistivity theory for surrounding ground condition prediction of TBM (TBM 주변 지반상태예측을 위한 전기비저항 이론식 유도 및 검증)

  • Hong, Chang-Ho;Lee, Minhyeong;Cho, Gye-Chun
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.22 no.1
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    • pp.135-144
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    • 2020
  • Since the depth of tunneling with tunnel boring machine (TBM) becomes deeper and deeper, the expense for site investigation for coring and geophysical survey increases to obtain the sufficient accuracy. The tunnel ahead prediction methods have been introduced to overcome this limitation in the stage of site investigation. Probe drilling can obtain the core and borehole images from a borehole. However, the space in TBM for the probe drilling equipment is restricted and the core from probe drilling cannot reflect the whole tunnel face. Seismic methods such as tunnel seismic prediction (TSP) can forecast over 100 m ahead from the tunnel face though the signal is usually generated using the explosive which can affect the stability of segments and backfill grout. Electromagnetic methods such as tunnel electrical resistivity prospecting system (TEPS) offer the exact prediction for a conductive zone such as water-bearing zone. However, the number of electrodes installed for exploration is limited in small diameter TBM and finally the reduction of prediction ranges. In this study, the theoretical equations for the electrical resistivity survey whose electrodes are installed in the face and side of TBM to minimize the installed electrodes on face. The experimental tests were conducted to verify the derived equations.

The Study on Modification Methods of Residents Registration Number System (재가방문 요양보호사의 대인관계스트레스가 이직의도에 미치는 영향 - 소진의 매개효과 검증)

  • Lee, Youn-Suk;Park, Kyung-il
    • The Journal of the Korea Contents Association
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    • v.16 no.11
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    • pp.369-383
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    • 2016
  • This study aims for strengthening the ability of home visiting care giver by figuring out interpersonal stress of bearing hardships which affect turnover intentions of home visiting care givers and by focusing on mediating effect of burnout. First, in summary, the analysis result was that the age of care givers and the presence of spouse are in relational factors correlated with burnout. Also age and experience of turnover have some connection with turnover intentions. Second, interpersonal stress of burnout and turnover intentions have static correlation. Third, the interpersonal stress represents increasing level of stress of burnout and the intervention of burnout shows static effects on turnover intentions of care givers. Suggestions of this study's results are, first, solution of interpersonal stress which home visiting care givers are facing should be improved by families' support or encouragement. In addition, the more professional and organized job training should be advanced to improve the understanding of various situations and coping skills. Second, the more interest should be need on business characteristics and environmental limitation. Also many centers that support care givers should reinforce their role. Third, to decrease the turnover intention which comes from interpersonal stress, doing some burnout research could be helpful and especially the legal regime which supports the research of burnout is essential.

Effects of Gunleetang Gagambang Extract on Antitumoral Immunological Response and the Side Effect Induced by Antitumoral Agents (군리탕가감방(君理湯加減方)이 항종양(抗腫瘍) 면역반응(免疫反應)과 항암제로 유발(誘發)한 부작용(副作用)에 미치는 영향(影響))

  • Yui, Guyng-Tea;Moon, Suk-Jae;Moon, Goo;Won, Jin-Hee
    • THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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    • v.4 no.1
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    • pp.71-87
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    • 1998
  • Even though appropriate immune response is necessary for the survival of the individual, excessive or insufficient immune Response might cause autoimmune or allergic disease. So the immune response must be controlled to the degree that is beneficial for the well being of the individual. This study was undertaken to know the effects of Gunleetang Gagambang on the immune system of the mouse. Gunleetang Gagambang has been used for cure of tumor as a traditional medicine without any experimental evidence to support the rational basis for its clinical use. This study was carried out to evaluate the possible therapeutic or antitumoral effects of Gunleetang Gagambang extract against tumor, and to carry out some mechanisms responsible for its effect. Some kinds of tumor were induced by the typical application of 3-methylcholanthrene(MCA) or by the implantation(s.c) of malignant tumor cells such as leukemia cells(3LL cells) or sarcoma cells(S180 cells). Treatment of the Gunleetang Gagambang on water-extract(dailly 1mg/mouse, i. p.) was continued for 7 days prior to tumor induction and after that the treatment was lasted for 20 days. Against squamous cell carcinoma induced by MCA, Gunleetang Gagambang decreased not only the frequency of tumor production but also the number and the weight of tumors per tumor bearing mice(TBM). Gunleetang Gagambang on also significantly suppressed the development of 3LL cell and S180 cell-implanted tumors in occurrence-frequency and their size. and some developed tumors were regressed by the continuous treatment of Gunleetang Gagambang extract into TBM. In vitro, treatment of Gunleetang Gagambang extract had no effect on the growth of some kinds of cell line such as FsaII, A431 strain but significantly inhibited the proliferation of 3LL, S180 cells and augmented the DNA synthesis of mitogen-activated lymphocytes. Gunleetang Gagambang also stimulated the migrative ability of leukocyte, the MIF and IL-2 production of T lymphocytes, but not IL 6 production of B cells. Gunleetang Gagambang administration to mice enhanced NK cells activities. These results demonstrated that Gunleetang Gagambang extract exhibited a significant prophylactic benefits against tumors and its antitumor activity was manifested depending on the type of tumor cells. And these results also suggested that effect of Gunleetang Gagambang might be chiefly due to nonspecitie enhancement of NK cell activities and cell-mediated immune responses.

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The Road Subsidence Status and Safety Improvement Plans (도로함몰 실태와 안전관리 개선 방안)

  • Bae, Yoon-Shin;Kim, Kyoon-Tai;Lee, Sang-Yum
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.1
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    • pp.545-552
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    • 2017
  • Ground subsidence can result in the formation of sinkholes, potholes, settlement of structures, and road subsidence. Road subsidence is described as the sudden collapse of the road surface into subsurface cavities caused by the loss of bearing capacity in the ground, such as the dissolution of limestone by fluid flow in the surface causing the formation of voids leading to subsidence at the surface. Road subsidence occurs about 665 times annually, and this incidence has been increasing until 2013. Damaged underground facilities, management negligence, and lowering of the ground water table have been the causes of road subsidence in Seoul. Seoul metropolitan government announced special management counter plans to relieve the anxieties and make the roads safe for passing. Construction sites, such as excavation works, need to be managed properly because they have strong potential to induce road subsidence. The aim of this study was to identify the main causes of road subsidence and suggest management plans. First, life cycle cost analysis revealed the daytime construction to be more appropriate than nighttime. In addition, by analyzing the limitations of using sand as a backfill material, it is proposed to use a flowable backfill material instead of sand. Finally, to reduce the blind spots, which is a problem in surveying the road pavement conditions of local governments, the road to be managed is divided into several zones, and a specialized agency is selected for each zone and a method of surveying the blind spots through collaboration is suggested.

Nitrogen Isotope Compositions of Synthetic Fertilizer, Raw Livestock Manure Slurry, and Composted Livestock Manure (화학비료, 가축분뇨 및 퇴비의 질소동위원소비)

  • Lim, Sang-Sun;Lee, Sang-Mo;Lee, Seung-Heon;Choi, Woo-Jung
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.4
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    • pp.453-457
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    • 2010
  • To investigate the difference in N isotope ratio ($^{15}N/^{14}N$, expressed as ${\delta}^{15}N$) among N sources (synthetic fertilizer, livestock manure, and manure compost), eight synthetic fertilizer, four livestock manure, and thirty-seven compost samples were collected and analyzed for ${\delta}^{15}N$. The mean ${\delta}^{15}N$ values of N sources were $-1.5{\pm}0.5$‰ (range: -3.9 to +0.5‰) for synthetic fertilizer, $+6.3{\pm}0.4$‰ (+5.3 to +7.2‰) for manure, and $+16.0{\pm}0.4$‰ (+9.3 to +20.9‰) for compost. The lower ${\delta}^{15}N$ of synthetic fertilizer was attributed to its N source, atmospheric $N_2$ of which ${\delta}^{15}N$ is 0‰ Meanwhile, more $^{15}N$-enrichment of compost than manure was assumed to be resulted from N isotopic fractionation (faster loss of $^{14}N$-bearing compound than $^{15}N$) associated with N loss particularly via $NH_3$ volatilization during composting. Therefore, our study shows that ${\delta}^{15}N$ values could successfully serve in discriminating two major N sources (synthetic fertilizer and compost) in agricultural system.

A Study on the Reason of Corporate CEOs' Tax Avoidance (법인기업 CEO의 조세회피이유에 관한 연구)

  • Park, Sang-Bong
    • Management & Information Systems Review
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    • v.29 no.1
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    • pp.79-96
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    • 2010
  • The purpose of this study is to investigate factors that affect corporate CEOs' tax avoidance, ultimately helping find how to fundamentally prevent the avoidance, establish a tax system that ensures tax payers' compliance and revise tax laws and regulations in a positive way. For the purpose, this researcher surveyed corporate CEOs with a questionnaire that contained many questions of various types, which was developed based on previous studies. Findings of the study can be summarized as follows. Main factors affecting tax avoidance were the application of tax provisions, the ability to understand tax laws and the expectation of tax avoidance. The more corporate CEOs' were influenced by the first and the third factors, the higher their propensity for tax avoidance was. On the contrast, corporate CEOs were lower in propensity for tax avoidance when they were more able to understand tax laws. Regarding the three factors' relative influences, tax avoidance was most affected by the expectation of tax avoidance, followed by the ability to understand tax laws and the application of tax provisions in order. Meanwhile, a multi-regression analysis using the sequential deletion technique showed that tax avoidance were affected by the application of tax provisions and the expectation of tax avoidance and that tax avoidance was most influenced by the application of tax provisions, followed by the expectation of tax avoidance. These findings indicate that the degree of corporate CEOs' tax avoidance may vary depending on social and environmental changes that their business face. Meanwhile, positive factors such as tax-bearing capacity and the procedure of tax calculation and negative factors such as management ethics and tax authorities' regulation are all thought to be not helping prevent tax avoidance.

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Healing Landscape Design for Hospital Outdoor Space - A Case of the Kyeongsang National University Hospital in Changwon - (치유경관의 개념을 적용한 병원 옥외공간 조경설계 - 창원 경상대학교 병원을 사례로 -)

  • Min, Byoung-Wook
    • Journal of the Korean Institute of Landscape Architecture
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    • v.41 no.1
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    • pp.82-92
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    • 2013
  • This paper presents a landscape design proposal for the Kyeongsang National University Hospital in Changwon, Kyeongsangnam-do. The site is located at 555 Samjeongja-dong, Seongsan-gu, Changwon, Kyeongsangnam-do, and its area is approximately $79,743.1m^2$. The goal of the design was to create a landscape that helps the patients' recovery and public well-being as well as respects the surrounding environment. In order to achieve this goal, three design subjects were considered: maximizing the healing functions of the landscape, promoting ecologically regenerative landscape, and increasing the aesthetic value of the landscape based on the local context. For the healing aspect, first, therapeutic plants were carefully selected and various healing programs were introduced to the open space area such as the sensory garden, meditative space, the medicinal herb garden, outdoor acupressure treatment facilities, remedial playground etc. In addition, as the importance of patient's privacy is emphasized in research, the space and circulation patterns were divided according to the characteristics of the users. For ecological consideration, the design proposed to preserve and extend the existing ridgeline with pine forest, and recover the natural water system and recycle the water for the landscape management. For the aesthetic experience of the people, in contrast to the surrounding evergreen forest, diverse deciduous and flowering plants were introduced to arouse a sense of the season, and fruit bearing trees for wildlife to create a specific mood of being in nature so that people can listen to the songs of the birds and watch squirrels play etc. In addition, all the spaces and facilities were designed and placed according to universal design principles so that there would be no barrier for the patients to use them. Also, a sustainable management scheme was suggested to maintain the landscape in ecological and economical ways.

Seismic Performance Preliminary Evaluation Method of Reinforced Concrete Apartments with Bearing Wall system (기존 철근콘크리트 벽식 공동주택의 내진 성능 예비 평가법에 관한 연구)

  • Chung, Lan;Woo, Sung-Sik;Choi, Ki-Young;Park, Tae-Won
    • Journal of the Korea Concrete Institute
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    • v.19 no.3
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    • pp.293-300
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    • 2007
  • In Korea, the seismic design regulations was established since 1988 about regularity scale of structures. However, It was not established about seismic performance and evaluation method as the most existing buildings was constructed before Earthquake-Resistant Design(1988). In this study, for model structures which are 4 units of non-seismic designed apartment and 3 units of seismic designed in Korea performed seismic performance evaluation by suggested KISTC (2004). And the result compare to evaluate Capacity Spectrum Method by using MIDAS Gen and SDS. As a result, we observed that suggested KISTC's method have overestimated for shear stress and drift index. The purpose of this study provides most conformity seismic performance evaluation process and the appropriate method of calculating the seismic performance index in Korea.

The Mechanism for Analgesic Effects of Electroacupuncture on Surgical Ankle Sprain Model Classified as Grade 3 in Rats (수술적 방법으로 유도된 3단계 발목염좌에 대한 전침의 진통기전 연구)

  • Yang, Seung-Bum;Choi, Suck-Jun;Lee, Sung-Ho;Kim, Min-Su;Sohn, In-Chul;Kim, Jae-Hyo
    • Korean Journal of Acupuncture
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    • v.30 no.4
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    • pp.220-229
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    • 2013
  • Objectives : Electroacupuncture(EA) has been used effectively in producing analgesia on ankle sprain pain of humans and animals. Currently to examine the underlying mechanisms of the EA-induced analgesia, the effects of EA on weight-bearing forces(WBR) were examined at ankle sprain classified as grade 3 in rats. Methods : The severe ankle sprain classified as grade 3 was induced surgically by ankle ligament injury in the Sprague-Dawley rats. WBR of the affected foot were examined to evaluate effects and mechanism of EA(2 Hz, 1 ms pulse width, 2 mA intensity, for 15 min) which was applied to either SI6, GB34, or GB39 acupoints. The rats were pretreated with naltrexone(10 mg/kg, i.p.) as an opioid receptor antagonist or phentolamine(5 mg/kg, i.p) as an ${\alpha}$-adrenoceptor antagonist at 30 min before EA. Results : The daily repeat EA at either SI6, GB34, or GB39 showed significant analgesic effects on the severe ankle sprain. Particularly, daily EA at GB34 showed more potent analgesic effect than the others. In addition, the naltrexone pretreatment completely blocked the analgesic effect of EA at GB34, indicating the involvement of the endogenous opioid system in mediating the effect of EA at GB34. However, the phentolamine pretreament blocked analgesic effects of EA at either SI6 or GB39, indicating the involvement of ${\alpha}$-adrenoceptors in mediating the effect of EA at either SI6 or GB39. Conclusions : These data suggest that EA-induced analgesia on ankle sprain pain is mediated through either endogenous opioids or ${\alpha}$-adrenoceptors dependant on acupoint specific pattern.

Reconstructed Adeno-Associated Virus with the Extracellular Domain of Murine PD-1 Induces Antitumor Immunity

  • Elhag, Osama A.O.;Hu, Xiao-Jing;Wen-Ying, Zhang;Li, Xiong;Yuan, Yong-Ze;Deng, Ling-Feng;Liu, De-Li;Liu, Ying-Le;Hui, Geng
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.8
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    • pp.4031-4036
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    • 2012
  • Background: The negative signaling provided by interactions of the co-inhibitory molecule, programmed death-1 (PD-1), and its ligands, B7-H1 (PD-L1) and B7-DC (PD-L2), is a critical mechanism contributing to tumor evasion; blockade of this pathway has been proven to enhance cytotoxic activity and mediate antitumor therapy. Here we evaluated the anti-tumor efficacy of AAV-mediated delivery of the extracellular domain of murine PD-1 (sPD-1) to a tumor site. Material and Methods: An rAAV vector was constructed in which the expression of sPD-1, a known negative regulator of TCR signals, is driven by human cytomegalovirus immediate early promoter (CMV-P), using a triple plasmid transfection system. Tumor-bearing mice were then treated with the AAV/sPD1 construct and expression of sPD-1 in tumor tissues was determined by semi quantitative RT-PCR, and tumor weights and cytotoxic activity of splenocytes were measured. Results: Analysis of tumor homogenates revealed sPD-1 mRNA to be significantly overexpressed in rAAV/sPD-1 treated mice as compared with control levels. Its use for local gene therapy at the inoculation site of H22 hepatoma cells could inhibit tumor growth, also enhancing lysis of tumor cells by lymphocytes stimulated specifically with an antigen. In addition, PD-1 was also found expressed on the surfaces of activated CD8+ T cells. Conclusion: This study confirmed that expression of the soluble extracellular domain of PD-1 molecule could reduce tumor microenvironment inhibitory effects on T cells and enhance cytotoxicity. This suggests that it might be a potential target for development of therapies to augment T-cell responses in patients with malignancies.