• 제목/요약/키워드: SRL

검색결과 94건 처리시간 0.023초

Stress and strain state in the segmental linings during mechanized tunnelling

  • Do, Ngoc-Anh;Oreste, Pierpaolo;Dias, Daniel;Antonello, Croce;Djeran-Maigre, Irini;Livio, Locatelli
    • Geomechanics and Engineering
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    • 제7권1호
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    • pp.75-85
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    • 2014
  • The application of the mechanized tunnelling has been extended in recent years. There are at present different approaches that are used in the design of segmental tunnel linings supported in mechanized tunnels. Even though segmental lining is utilized for mechanized tunnels, its behaviour is still quite unclear under in situ stress and there is a lack of data regarding the distribution of stresses inside segmental linings. So far no single effective calculation method exists for segmental lining design. The lack of clear solutions makes the use of segmental lining to be more expensive due to the adoption of greater safety factors. Therefore, a particular attention must be given in order to obtain data from monitored tunnels which permits to validate design methods. In this study, strain measurements, which were conducted during the construction of twin tunnels in the Bologna-Florence railway line, have been presented. The behaviour of segmental lining during the excavation and the influence of a new tunnel excavation on an existing tunnel have been shown through the measured data. The data are then compared with the results obtained with Einstein and Schwartz's method and Duddeck and Erdmann's method, which permits to highlight the fact that the two analytical methods underestimate structural forces induced in the segmental lining and then must be used with caution.

SMA-based devices: insight across recent proposals toward civil engineering applications

  • Casciati, Sara
    • Smart Structures and Systems
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    • 제24권1호
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    • pp.111-125
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    • 2019
  • Metallic shape memory alloys present fascinating physical properties such as their super-elastic behavior in austenite phase, which can be exploited for providing a structure with both a self-centering capability and an increased ductility. More or less accurate numerical models have been introduced to model their behavior along the last 25 years. This is the reason for which the literature is rich of suggestions/proposals on how to implement this material in devices for passive and semi-active control. Nevertheless, the thermo-mechanical coupling characterizing the first-order martensite phase transformation process results in several macroscopic features affecting the alloy performance. In particular, the effects of day-night and winter-summer temperature excursions require special attention. This aspect might imply that the deployment of some devices should be restricted to indoor solutions. A further aspect is the dependence of the behavior from the geometry one adopts. Two fundamental lacks of symmetry should also be carefully considered when implementing a SMA-based application: the behavior in tension is different from that in compression, and the heating is easy and fast whereas the cooling is not. This manuscript focuses on the passive devices recently proposed in the literature for civil engineering applications. Based on the challenges above identified, their actual feasibility is investigated in detail and their long term performance is discussed with reference to their fatigue life. A few available semi-active solutions are also considered.

Towards defining a simplified procedure for COTS system-on-chip TID testing

  • Di Mascio, Stefano;Menicucci, Alessandra;Furano, Gianluca;Szewczyk, Tomasz;Campajola, Luigi;Di Capua, Francesco;Lucaroni, Andrea;Ottavi, Marco
    • Nuclear Engineering and Technology
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    • 제50권8호
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    • pp.1298-1305
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    • 2018
  • The use of System-on-Chip (SoC) solutions in the design of on-board data handling systems is an important step towards further miniaturization in space. However, the Total Ionizing Dose (TID) and Single Event Effects (SEE) characterization of these complex devices present new challenges that are either not fully addressed by current testing guidelines or may result in expensive, cumbersome test configurations. In this paper we report the test setups, procedures and results for TID testing of a SoC microcontroller both using standard $^{60}Co$ and low-energy protons beams. This paper specifically points out the differences in the test methodology and in the challenges between TID testing with proton beam and with the conventional gamma ray irradiation. New test setup and procedures are proposed which are capable of emulating typical mission conditions (clock, bias, software, reprogramming, etc.) while keeping the test setup as simple as possible at the same time.

정화 처리토가 렌틸(콩과식물)의 지상부 및 뿌리 성장에 주는 영향에 대한 정량평가 (Quantifying Inhibitory Effects of Reclaimed Soils on the Shoot and Root Growth of Legume plant Lentil(Lens culinaris))

  • 박혜선;강수아;배범한
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제26권5호
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    • pp.1-8
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    • 2021
  • A series of pot experiments were conducted to quantitatively estimate inhibitory effects of reclaimed soil on the growth of Lentil (Lens culinaris) with two soils remediated by land farming (DDC) and low temperature thermal desorption(YJ), respectively. After cultivation in a growth chamber for 8 days, plants were harvested for the analysis of 8 indices including chlorophyll-a and carotenoid in leaves, shoot fresh weight, root dry weight, root length, number of later roots, specific root length (SRL) as well as germination rate in comparison to control experiment conducted on nursery soil. Root length was estimated by SmartRoot program from the digital images of the roots. The results showed germination rate on YJ and DDC soil decreased 29 and 71%, respectively. In comparison to the control, the averaged value of the 8 indices for YJ and DDC soil showed overall growth inhibition was 48 and 68%, respectively. When the same experiment was conducted with 25% (W/W) vermiculate amended soil, plant growth on each soil was comparable to that of the control. The results implies reclaimed soils requires additional processes and/or amendments to reuse for plant growth.

Effect of Different Degradable Protein and Starch Sources on the Blood Metabolites and Rumen Biochemical Profile of Early Weaned Crossbred Calves

  • Pattanaik, A.K.;Sastry, V.R.B.;Katiyar, R.C.
    • Asian-Australasian Journal of Animal Sciences
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    • 제12권5호
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    • pp.728-734
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    • 1999
  • Thirty new born crossbred (Bos taurus${\times}$Bos indicus) calves, divided randomly in a $3{\times}2$ factorial design, were fed calf starters containing one of three protein sources i.e., groundnut cake (GN), cottonseed meal (CS) and meat and bone meal (MB) along with either raw (M) or gelatinized maize (MG) for 90d. Milk was fed upto 56d of age. Green oats and respective calf starters were offered from 14d of age onwards ad lib. Clinical profile of serum suggested significantly (p<0.05) higher albumin and lower alanine aminotransferase activity due to CS feeding. Alklaine phosphatase activity varied significantly (p<0.05) among dietary treatments showing interaction between protein and starch sources. Inclusion of gelatinized maize resulted in significantly higher concentration of serum globulin (p<0.05) and alkaline phosphatase activity (p<0.01). reduced (p<0.05) ruminal pH was accompanied by a significant decrease (p<0.01) in $NH_3-N$ concentration in the strained rumen liquor (SRL) of MG fed calves. Ruminal amylase activity was lower (p<0.05) on MG diets. Alanine aminotransferase activity in the rumen exhibited a significant (p<0.01) interaction between protein and starch sources. While feeding of CS significantly (p<0.01) reduced alanine aminotransferase activity, inclusion of thermally processed maize reduced (p<0.01) both aspartate and alanine aminotransferase activities in the rumen. The overall blood picture was similar among treatments, whereas rumen metabolites especially enzyme activities, seems to be altered with source of degradable protein an starch.

EFFECT OF SUPPLEMENTING UREA MOLASSES MINERAL BLOCK LICKS ON BACTERIAL PRODUCTION RATE IN THE RUMEN OF CROSSBRED CALVES

  • Garg, M.R.;Gupta, B.N.
    • Asian-Australasian Journal of Animal Sciences
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    • 제5권3호
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    • pp.533-539
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    • 1992
  • Sixteen crossbred (Sahiwal $\times$ Holstein) male rumen fistulated calves of 18 to 24 months of age were randomly divided into four groups of four animal, each. Animals in all the groups were fed wheat straw ad lib as basal roughage. However, the animals in group I were fed concentrate mixture at maintenance level, whereas, the animals in groups II, III and IV had free access to existing, modified (A) and modified (B) urea molasses mineral block licks respectively. Daily wheat straw intake (kg) was significantly (p<0.01) higher in groups II ($4.20{\pm}0.13$), III ($4.07{\pm}0.16$) and IV ($4.22{\pm}0.20$) as compared to group I ($3.21{\pm}0.14$). Total N and TCA precistrained rumen liquor) was significantly higher in groups II ($22.36{\pm}0.25$), III ($21.63{\pm}0.25$) and IV ($21.77{\pm}0.55$) as compared to group I ($18.31{\pm}0.41$). Bacterial production rate (g/day and g/kg digestible organic matter intake) were non-significantly different amongst groups I ($214.4{\pm}13.28;\;85.38{\pm}3.69$); II ($198.7{\pm}5.70;\;86.17{\pm}3.53$); III ($214.4{\pm}8.19;\;96.15{\pm}2.16$) and IV ($218.2{\pm}10.62;\;94.44{\pm}5.52$). Similarly, percent efficiency of N incorporation into bacterial protein was not found significantly different amongst groups I, II, III and IV. These studies indicate that when concentrate mixture (upto maintenance level) in the diet of ruminants was replaced with UMMB licks, various N fraction in SRL and efficiency of bacterial production rates in the rumen were not affected.

문헌정보학 교육에서 문제기반학습법 적용이 자기조절학습능력 향상에 미치는 효과 - 인지적·동기적 구성요소를 중심으로 - (The Effects of Problem-Based Learning on Self-Regulated Learning Ability in LIS Education: Based on Cognitive and Motivational Components)

  • 이정미
    • 한국문헌정보학회지
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    • 제47권4호
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    • pp.103-124
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    • 2013
  • 본 연구는 문헌정보학과 교과목에 문제기반학습을 적용한 자기조절학습모형을 설계해 실행한 후 학습자의 인지적 동기적 자기조절학습능력의 변화를 살펴보는 것을 목적으로 하는 연구이다. 이를 위해 본 연구는 수강생들의 자기조절학습능력의 변화를 사전 사후 동일 검사지로 설문조사하여 살펴보았다. 인지적 동기적 자기조절학습능력은 각각 일반적 영향과 상관관계를 살펴보고 해당 자기조절학습능력의 세부하위요인들의 학습 전 후 변화를 측정하였으며 통계적 유의성은 대응표본 t-test로 분석하였다. 연구결과 문제기반학습법은 학생들의 인지적 동기적 자기조절학습능력의 향상에 효과가 있음을 밝혀냈으며 동기적 자기조절학습능력에 있어서는 후속 연구에 대한 가능성을 발견하였다.

Exome sequencing in a breast cancer family without BRCA mutation

  • Noh, Jae Myoung;Kim, Jihun;Cho, Dae Yeon;Choi, Doo Ho;Park, Won;Huh, Seung Jae
    • Radiation Oncology Journal
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    • 제33권2호
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    • pp.149-154
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    • 2015
  • Purpose: We performed exome sequencing in a breast cancer family without BRCA mutations. Materials and Methods: A family that three sisters have a history of breast cancer was selected for analysis. There were no family members with breast cancer in the previous generation. Genetic testing for BRCA mutation was negative, even by the multiplex ligation-dependent probe amplification method. Two sisters with breast cancer were selected as affected members, while the mother of the sisters was a non-affected member. Whole exome sequencing was performed on the HiSeq 2000 platform with paired-end reads of 101 bp in the three members. Results: We identified 19,436, 19,468, and 19,345 single-nucleotide polymorphisms (SNPs) in the coding regions. Among them, 8,759, 8,789, and 8,772 were non-synonymous SNPs, respectively. After filtering out 12,843 synonymous variations and 12,105 known variations with indels found in the dbSNP135 or 1000 Genomes Project database, we selected 73 variations in the samples from the affected sisters that did not occur in the sample from the unaffected mother. Using the Sorting Intolerant From Tolerant (SIFT), PolyPhen-2, and MutationTaster algorithms to predict amino acid substitutions, the XCR1, DLL1, TH, ACCS, SPPL3, CCNF, and SRL genes were risky among all three algorithms, while definite candidate genes could not be conclusively determined. Conclusion: Using exome sequencing, we found 7 variants for a breast cancer family without BRCA mutations. Genetic evidence of disease association should be confirmed by future studies.

Growth and Mineral Contents of Spinach (Spinacia oleracea L.) and Radish (Raphanus sativus L.) as Related with a Low Dose Gamma Irradiation

  • Hwangbo, Jun-Kwon;Kim, Jae-Sung;Lim, Ji-Hyeok;Baek, Myung-Hwa;Chung, Byung-Yeoup;Kim, Jin-Hong
    • 환경생물
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    • 제21권4호
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    • pp.400-404
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    • 2003
  • This study was to evaluate the effects of gamma irradiation on the germination, nutrient concentrations and growth of spinach and radish. Both the spinach and radish seeds exhibited relatively higher germination rates in response to the low doses of gamma irradiation compared to the non -irradiated control. Leaf DW of the radish did not respond to gamma irradiation but that of the spinach increased significantly in response to a gamma radiation of 4 Gy (P< 0.05). Leaf growth parameters of the spinach including the leaf area and SLA (leaf area/leaf dry weight) also demonstrated increased responses to gamma irradiation. R/S (root dry weight/shoot dry weight), root DW and root length of the spinach exhibited a positive response to gamma irradiation while those of the radish did not. In contrast, SRL (root length/root dry weight) significantly decreased with gamma irradiation at 8 Gy for the spinach, but not for the radish. The tissue nitrogen concentrations of the spinach showed an increased response to gamma irradiation while that of the radish did not. Furthermore, higher concentrations of phosphorus, potassium, calcium and magnesium were found in the irradiated spinach, but not in the irradiated radish. It seems that the non-specific physiological and/or biochemical activities of spinach might be accelerated by gamma irradiation, possibly accounting for the stimulation of nutrient uptake from the root media and early biomass accumulation in the current study.

Knowledge, Attitudes and Practices of Sudanese Women Regarding the Pap Smear Test and Cervical Cancer

  • Almobarak, Ahmed O;Elbadawi, Ayman A;Elmadhoun, Wadie M;Elhoweris, Mohammed H;Ahmed, Mohammed H
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권2호
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    • pp.625-630
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    • 2016
  • Background: Despite the established role of the Pap smear test (PST) in prevention and early detection of cervical cancer, it is still rarely practiced in Sudan. Many challenges hinder the establishment of an effective cervical cancer screening program, including socio-cultural factors. Therefore, this study aimed to investigate the knowledge, attitudes and practices (KAP) of Sudanese women with regard to the Pap smear test and cervical cancer. Materials and Methods: A total of 500 married women aged 14 to 58 years were recruited from obstetric clinics, hospitals and universities in Khartoum in 2014. Data were collected using a standardized, pretested questionnaire that inquired socio-demographic characteristics and their KAP about cervical cancer and the PST. Results: More than 52% of participating women were above 30 years of age, and the majority (78.8%) were university degree holders. A total of 486 (97.2 %) of participants were resident in urban areas of Khartoum State. However about 48% of the respondents had never heard about PST, and only 15.8% of the participants had undergone a Pap smear test previously; 46.6% (233/500) knew that the human papilloma virus (HPV) was the causative agent, but only 39.2% (196/500) had heard about HPV vaccination, and only 11.4% (57/500) had received the vaccine. However 68% of the respondents agreed to do Pap smear if properly informed about the test and 75.4% of the respondents agreed to participate in a cervical cancer screening program. Conclusions: Despite a high educational level, less than half of our participants had accurate knowledge about cervical cancer, HPV, and cervical cancer screening. Health education about cervical cancer, HPV and sexually transmitted infections and the role of PST in cervical cancer prevention are crucial when designing interventions aimed at improving cervical cancer screening for Sudanese women.