• Title/Summary/Keyword: GB/T

Search Result 132, Processing Time 0.022 seconds

Ultimate capacity of welded box section columns with slender plate elements

  • Shen, Hong-Xia
    • Steel and Composite Structures
    • /
    • v.13 no.1
    • /
    • pp.15-33
    • /
    • 2012
  • For an axially loaded box-shaped member, the width-to-thickness ratio of the plate elements preferably should not be greater than 40 for Q235 steel grades in accordance with the Chinese code GB50017-2003. However, in practical engineering the plate width-to-thickness ratio is up to 120, much more than the limiting value. In this paper, a 3D nonlinear finite element model is developed that accounts for both geometrical imperfections and residual stresses and the ultimate capacity of welded built-up box columns, with larger width-to-thickness ratios of 60, 70, 80, and 100, is simulated. At the same time, the interaction buckling strength of these members is determined using the effective width method recommended in the Chinese code GB50018-2002, Eurocode 3 EN1993-1 and American standard ANSI/AISC 360-10 and the direct strength method developed in recent years. The studies show that the finite element model proposed can simulate the behavior of nonlinear buckling of axially loaded box-shaped members very well. The width-to-thickness ratio of the plate elements in welded box section columns can be enlarged up to 100 for Q235 steel grades. Good agreements are observed between the results obtained from the FEM and direct strength method. The modified direct strength method provides a better estimation of the column strength compared to the direct strength method over the full range of plate width-to-thickness ratio. The Chinese code and Eurocode 3 are overly conservative prediction of column capacity while the American standard provides a better prediction and is slightly conservative for b/t = 60. Therefore, it is suggested that the modified direct strength method should be adopted when revising the Chinese code.

A Study on Acupuncture-generated Blood-Oxygen-Level Dependant Signals in Substantia Nigra and Other Areas in Extrapyramidal Tract (대뇌흑질과 추체외로에서 자침에 의한 BOLD 신호)

  • Choe, Il-Hwan;Park, Hi-Joon;Yoon, Hyo-Woon;Shin, Hyung-Chul;Lee, Sang-Hoon;Lee, Yun-Ho;Lim, Sabina
    • Journal of Acupuncture Research
    • /
    • v.25 no.1
    • /
    • pp.211-219
    • /
    • 2008
  • 목적 : 전통적으로 태충($LR_3$)과 양릉천($GB_{34}$)은 운동기능과 관련된 질환에 사용되어 왔다. 우리는 두뇌에 신경독을 주입하여 파킨슨병 쥐모델을 제작하였고, 쥐는 운동기능이 손상되고 도파민성 신경세포가 선택적으로 소멸하였다. 병증 모델 쥐에게 태충과 양릉천에 자침한 결과 운동기능이 개선되고 신경세포보호효과가 나타남을 관찰한 바 있다. 이에 실제로 태충과 양릉천에 자침하여 운동기능과 관련된 추체외로 영역에서 신경의 활성화가 나타나는지를 fMRI를 통하여 관찰하였다. 방법 : 자침은 수기침을 선택하였으며, 혈위는 (1) 태충, (2) 양릉천, (3) 태충+양릉천의 세군데를 설정하였고, 자침에 대한 대조자극으로 피부자극을 채택하였다. fMRI 스캐너는 3T를 사용하였고 뇌신경 활성화의 신호는 BOLD(blood-oxygen-level dependant)를 관찰하였다. 두뇌에서 관찰부위는 중뇌를 중심으로 추체외로로 한정하였다. 결과 : 태충에 자침하였을 때 두뇌의 substantia nigra, subthalamic nucleus, red nucleus, pons 등이 활성화 되었다. 양릉천에 자침하였을 때 substantia nigra, subthalamic nucleus, caudate nucleus, thalamus가 활성화 되었다. 태충과 양릉천에 동시에 자침하였을 때는 substantia nigra, subthalamic nucleus, red nucleus, globus pallidus가 활성화되었다. 대조자극에 의해서는 위의 영역들이 활성화되지 않았다. 결론 : 태충, 양릉천, 태충+양릉천 자극은 대뇌에서 추체외로 영역을 활성화시키며 특히 substantia nigra의 활성화는 파킨슨병과 같은 질환의 조절가능성을 시사한다.

  • PDF

Pragmatic Combinations of Acupuncture Points for Lateral Epicondylalgia are Unreliable in the Physiotherapy Setting

  • Alvim, Danielle T.;Ferreira, Arthur S.
    • Journal of Acupuncture & Meridian Studies
    • /
    • v.11 no.6
    • /
    • pp.367-374
    • /
    • 2018
  • This study describes the reliability of pragmatic combinations of acupuncture points for lateral epicondylalgia (LE) as prescribed by physiotherapists who were experts in acupuncture. Raters (n = 14; 33-59 years) independently prescribed acupuncture points for 30 simulated human patients with LE who were surveyed via a printed questionnaire. The frequency and cooccurrence of acupuncture points prescribed for patients with lateral epicondylitis were assessed. Absolute agreement and Light's kappa (${\kappa}_{Light}$) with 95% confidence interval (CI) were used to quantify the interrater agreement. Raters prescribed 103 unique acupuncture points in different combinations with a median (min-max) of 5 (0-11) acupuncture points. The most prescribed acupuncture point was LI-11 (297 of 420; 71%), and the most common cooccurring acupuncture points were LI-11 and LI-4 (160 of 420; 38%). The absolute agreement for prescribing the acupuncture points ranged from 70% (point GB-20) to 0% (points LI-10, SP-6, LI-11, GB-34, LI-12, and LI-4). Point LR-3 showed the highest interrater reliability for prescribing the acupuncture points [${\kappa}_{Light}=0.112$, 95% CI = (0.055-0.194)], whereas point LI-4 showed the lowest reliability [${\kappa}_{Light}=-0.003$, 95% CI = (-0.024 to 0.024)]. These findings suggest that pragmatic prescriptions of acupuncture points for LE are unreliable among physiotherapists who are experts in acupuncture. Explicit, high-level evidence-based rules for prescribing and teaching combinations of acupuncture points for LE are warranted.

Effect of Incorporation Times of Green Barley and Hairy Vetch on Rice Yield in Paddy Soil with Liquid Pig Manure (돈분액비를 시용한 녹비보리 및 헤어리베치의 혼입시기가 벼 수량에 미치는 영향)

  • Kang, Se-Won;Seo, Dong-Cheol;Lee, Sang-Gyu;Seo, Young-Jin;Park, Ju-Wang;Ryu, Jin-Hee;Kim, Min-Tae;Kang, Hang-Won;Heo, Jong-Soo;Cho, Ju-Sik
    • Korean Journal of Environmental Agriculture
    • /
    • v.32 no.4
    • /
    • pp.287-293
    • /
    • 2013
  • BACKGROUND: Soil incorporation of green manure crop(GMC) and liquid pig manure(LPM) is one of the methods for reduction of chemical fertilizer and the increase of crop yield. The objective of this study was to select optimal incorporation time of GMCs on growth and nutrient property in paddy soil treated LPM. METHODS AND RESULTS: The kinds of GMCs were Hordeum vulgare L.(green barley, GB) and Vicia villosa roth(hairy vetch, HV). The effects of GMCs on rice yield were investigated under different incorporation times of GMCs(LPM1: at 25 days before rice transplantation, LPM2: at 18 days before rice transplantation, LPM3: at 11 days before rice transplantation). In GB treatments, the biomass was greater in the order of $$LPM3{\geq_-}LPM2{\geq_-}LPM1$$. Contents of N, P and K ranged 1.21~1.28, 0.36~0.38 and 1.41~1.45%, respectively, regardless of incorporation times. The amounts of nutrient supply in GB treatments were higher in LPM1 than those in other treatment conditions. In GB treatments, rice yields in LPM1, LPM2 and LPM3 were 523, 525 and 526(increasing yield 3% than control) kg/10a, respectively. In HV treatments, the amounts of nutrient supply were higher in the order of $$LPM3{\geq_-}LPM2{\geq_-}LPM1$$. Rice yields were 530 kg/10a for LPM1, 531 kg/10a for LPM2, 535 (increasing yield 5% than control) kg/10a for LPM3 in HV treatments, respectively. CONCLUSION(s): The optimum incorporation time of green barley and hairy vetch was at 11 days before rice transplantation(LPM3) in paddy soil with liquid pig manure.

Effect of confinement on flexural ductility design of concrete beams

  • Chen, X.C.;Bai, Z.Z.;Au, F.T.K.
    • Computers and Concrete
    • /
    • v.20 no.2
    • /
    • pp.129-143
    • /
    • 2017
  • Seismic design of reinforced concrete (RC) structures requires a certain minimum level of flexural ductility. For example, Eurocode EN1998-1 directly specifies a minimum flexural ductility for RC beams, while Chinese code GB50011 limits the equivalent rectangular stress block depth ratio at peak resisting moment to achieve a certain nominal minimum flexural ductility indirectly. Although confinement is effective in improving the ductility of RC beams, most design codes do not provide any guidelines due to the lack of a suitable theory. In this study, the confinement for desirable flexural ductility performance of both normal- and high-strength concrete beams is evaluated based on a rigorous full-range moment-curvature analysis. An effective strategy is proposed for flexural ductility design of RC beams taking into account confinement. The key parameters considered include the maximum difference of tension and compression reinforcement ratios, and maximum neutral axis depth ratio at peak resisting moment. Empirical formulae and tables are then developed to provide guidelines accordingly.

Exploring the Causal Relationships in the Criteria for Excellence Performance of China

  • Ma, Yizhong;Ree, Sang-Bok
    • International Journal of Quality Innovation
    • /
    • v.9 no.3
    • /
    • pp.145-162
    • /
    • 2008
  • Since the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China published the GB/T19580-2004: Criteria for Excellence Performance of China, many enterprises in China have adopted the Criteria to enhance their organization business management and to assess or self-assess organization performance. On the bases of both the Criteria for Excellence Performance of China and the survey data from China Association for Quality (CAQ), this paper systematically explores the relationships among 'leadership', 'strategy planning', 'customer and market', 'information, analysis and improvement', 'resources management', 'process management', and 'performance results' by using structural equations modeling and validates some of the anecdotal beliefs in quality management. This quantitative analysis provides a guideline for organizations in China to identify causal linkage among core value of total quality management and to identify strengths, deficiency, and opportunities to enhance competitive advantages and ensure the future business success.

Application of Traditional Acupuncture on Canine Intervertebral Disc Disease (개에서 추간판 질환에 대한 침술치료 증례)

  • 정성목;박수원
    • Journal of Veterinary Clinics
    • /
    • v.21 no.1
    • /
    • pp.49-51
    • /
    • 2004
  • A four-year-old female Pekingese dog was presented with intermittent ambulatory hindlimb lameness and severe back pain. The course of the disease was acute and static and 5 days passed by until presentation. In neurological examination, severe back pain and slightly decreased proprioception in right hindlimb were shown. In radiographic examination, radiopacity was increased at T10-11 intervertebral disc space. According to the history taking, neurological examination and radiographic examination, it was tentatively diagnosed as intervertebral disc disease (IVDD). Conservative treatment was performed including cage rest, medication with prednisolone and traditional acupuncture. Acupoints were GV-6, GV-7, BL-18, BL-19. BL-40 and GB-34. Dry needlings rested for 20 minutes. Just after the first acupuncture treatment back pain was significantly decreased. With additional acupuncture treatment, all the clinical signs were not observed. It is considered that conservative therapy including traditional acupuncture, medication and cage rest might be the first choice of therapeutic method for Grade I or II IVDD in dogs.

Investigation and Countermeasure of Sheath Circulating Current in the 362kV GIS (362kV GIS 외함 순환전류에 의한 접지본드 과열현상 및 대책)

  • Lee, J.H.;Kim, S.K.;Kim, S.T.;Shin, M.C.
    • Proceedings of the KIEE Conference
    • /
    • 2003.07a
    • /
    • pp.546-548
    • /
    • 2003
  • 본 논문에서는 362kV GIS 외함 유도 순환전류에 의한 접지본드과열에 대하여 원인을 분석하고 대책을 마련하는 것을 목적으로한다. 원인분석에는 접지본드 과열현상과 과열원인을 GIB 시스전류계산식을 이용하여 계산결과를 도출하였고 전자과도해석 프로그램(EMTP : Electromagnetic Transient Program)에 의한 분석을 통하여 원인을 분석하고 대책을 마련하여 과열현상을 방지하고자 한다.

  • PDF

A Study on the Synchronization of GFP Signal in NG-SDH System (NG-SDH시스템에서의 GFP 신호동기에 관한 연구)

  • Lee Chang-Ki;Ko Je-Soo
    • The KIPS Transactions:PartC
    • /
    • v.12C no.1 s.97
    • /
    • pp.53-62
    • /
    • 2005
  • The NG-SDH system requires signal synchronization to synchronize incoming ethernet signal with GFP frame. The foreign nation research completes a chipset development until now and it secures a relation technique, but it does not secure a relation technique from domestic. Therefore, in this paper, we presented with signal synchronization method of Ethernet signal through GFP frame. We knew that the synchronized method of Ethernet signal through GFP-F must apply ingress & egress buffer and GFP Idle. We understood that the synchronized method of Ethernet signal through GFP-T must apply GFP Idle and $65B{\_}PAD$, and require maximum 3-bit addition & deletion of idle. Also we showed signal synchronization realization through simulation and obtained MTIE/TDEV characteristics and peak to peak jitter in egress output.

450 Gbps Low-cost Intensity Modulation with Direct Detection (IM/DD) Wave Length Division Multiplexing (WDM-PON) for 5G Fronthaul

  • Kawan Faiq Ahmed;Asaad Mubdir Jassim Al-Hindawi
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.17 no.12
    • /
    • pp.3310-3329
    • /
    • 2023
  • This work designs an eighteen-channel bidirectional Intensity Modulation with Direct Detection (IM/DD) Wavelength Division Multiplexing-Passive Optical Network (WDM-PON) system. The proposed system meets the requirement of the ITU-T 5G fronthaul link suggested design in G-series Recommendations-Supplement 66. The newly designed system, with a 25Gb/s/λ data rate (450Gbps as a system capacity), has been tested and simulated using OptiSystem V.19 software. The system has been evaluated by the BER with respect to variable the optical span and CW laser power. Based on the ITU-T recommendations, the simulation results demonstrate that this system might be used as an F1 and as an Fx 5G fronthaul link for functional split choices starting from options 1 to 7a. These options are required under 25Gbps/λ for each upstream and downstream link direction. Furthermore, the proposed system utilized a bidirectional single-mode optical fiber within short optical spans of up to 10 km. The proposed system is characterized by a low-cost, simple, DSP-free and amplifier-free system with a reasonable system capacity.