• Journal of Information Processing Systems
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• v.15 no.6
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• pp.1350-1364
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• 2019

The ice damage occurs frequently in cold and dry region of western China in winter ice period and spring thaw period. In the drift ice condition, it is easy to form different extrusion force or impact force to damage tunnel lining, causing project failure. The failure project could not arrive the original planning and construction goal, giving rise to the water allocation pressure which influences diversion irrigation and farming production in spring. This study conducts the theoretical study on contact-impact algorithm of drift ices crashing diversion tunnel based on the symmetric penalty function in finite element theory. ANSYS/LS-DYNA is adopted as the platform to establish tunnel model and drift ice model. LS-DYNA SOLVER is used as the solver and LS-PREPOST is used to do post-processing, analyzing the damage degrees of drift ices on tunnel. Constructing physical model in the experiment to verify and reveal the impact damage mechanism of drift ices on diversion tunnel. The software simulation results and the experiment results show that tunnel lining surface will form varying degree deformation and failure when drift ices crash tunnel lining on different velocity, different plan size and different thickness of drift ice. The researches also show that there are damages of drift ice impact force on tunnel lining in the thawing period in cold and dry region. By long time water scouring, the tunnel lining surfaces are broken and falling off which breaks the strength and stability of the structure.

• Fashion & Textile Research Journal
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• v.8 no.3
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• pp.357-362
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• 2006

This study is to evaluate the objective sensibility of the commercial lining fabrics. Five kinds of the linings were collected by adding taffetas with four kinds of fibers (polyester, nylon, rayon, and acetate) to one polyester stretch fabric. The six basic mechanical and hand properties were studied by using KES-FB system (Kawabata Evaluation System). The result of measuring the mechanical properties shows that polyester has high bending rigidity (B), that polyester-stretch has a high value of linearity of load-extension curve (LT), tensile energy (WT), tensile resilience (RT), and coefficient of friction (MIU) and a low value of bending rigidity(B), shear property, and geometrical roughness (SMD). The nylon has a high value of bending rigidity (B), shear property, and compression resilience (RC). The rayon has a high value of coefficient of friction (MIU) and linearity of compression-thickness curve (LC) and a low value of shear property, and the acetate has a low value of shear property. The result of hand value shows that polyester, nylon, and acetate are a high value of KOSHI (stiffness), NUMERI (smoothness), and FUKURAM (fullness & softness), and they feel stiff and massive, that rayon has a low value of NUMERI and FUKURAMI. The total result of hand value shows that polyester taffeta and polyester stretch fabric are about the same as the best material for the lining of a woman's dress for spring and summer, and the next thing is acetate, but nylon and rayon are somewhat inferior materials. This provides a fundamental data for the comfortable clothing production of a higher value-added product through the study on the mechanical and hand properties of the lining as well as the right side of fabrics.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.2
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• pp.259-267
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• 2008

This in vitro study aimed to investigate the influence of flowable composite lining with different thicknesses on the marginal quality. One hundred twenty cavities, each preparated with proximal boxtype( 3mm of bucco-lingual width, 2mm of mesio-distal depth and gingival margin of 1mm supra-CEJ) were randomly dived into four groups. group I : Tetric ceram filling alone(control group) group II: 0.5mm thickness Tetric flow + Tetric ceram filling group III: 1.5mm thickness Tetric flow + Tetric ceram filling group IV: 2.5mm thickness Tetric flow + Tetric ceram filling The followings are the results: 1. Group II showed significantly less microleakage compared to group I(control group)(p<0.05). 2. There was no statistically significant difference between group III, IV and group I(p>0.05). 3. Group II showed significantly less microleakage compared to group III, IV(p<0.05). 4. There was microleakage more or less in all group. It was concluded that 0.5mm flowable composite lining improved cavity adaptation and marginal sealing.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.5
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• pp.150-159
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• 2011

The need of securing the stability and extending service lives by efficient maintenance of deteriorated tunnels for several decades has been increased. The stability and the usability of conventional tunnels can be decreased by change of physical properties of the surrounding ground, geometrical properties of the tunnel, an underground water level, environmental conditions, oxidation of lining and the breakdown of constituent materials. In respect of a long-term view, it is need to check all sorts of degradation, the degree of damage and durability to improve the serviceability and to come up with measures to maintain effectively. This paper is about study to analyze the stability of conventional tunnels(American Steel Support Method. ASSM). Three tunnels are chosen in those built in the 1930s and 1960s and the locations of tunnels are selected variously(ChungCheong, GyungBuk, GangWon, Jeolla, etc.) to secure reliability of this study. The state of repair and reinforcement of linings, cracks, and thickness and strength of lining of conventional tunnels in service are researched, compared and analyzed. The crack gauge, the GPR, the schmitt hammer was used for the crack investigation, cavitation, the strength respectively. By using these, the comparative analysis for conventional tunnels was conducted. As a result, there are more cracks in tunnels built in the 1930s than those of tunnels built in the 1960s, and lining strength of the 1930s is higher than those of the 1960s. The thickness of lining in tunnels built in the 1960s is higher than those in tunnels built in the 1930s. In proportion to thickness, cavitation occurred more frequently in tunnels built in the 1960s compared to those in tunnels built in the 1930s.

• Journal of the Korean Geotechnical Society
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• v.33 no.8
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• pp.17-27
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• 2017

Gangwon province which is located in northeast of Korea is the coldest region where average daily temperature is below zero during winter while the other regions are above zero. However, there have been insufficient researches on the insulation design and the effect of the insulation on the freezing damages, even though freezing damages were reported consistently in the lining of road tunnel during winter. In this study, to investigate the effect of insulations on the reduction of freezing damages, numerical analysis was performed considering geotechnical and meteorological characteristics in Gangwon province during winter. As a result, it was found that thickness of concrete and shotcrete in lining had negligible effect on the freezing depth while the insulation had significant effect on it. In addition, because the freezing depth is greatly affected by the thermal conductivity of the ground behind the lining in the period of cold weather, these effects should be considered in the estimation of the insulation thickness.

• Tunnel and Underground Space
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• v.14 no.1
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• pp.35-42
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• 2004

Impact-echo is a method for non-destructive testing of concrete structure. This method is based on the use of impact-generated stress wave which is propagated and reflected from internal flaws within concrete structure and external surface. In this study, we performed non-destructive testing using impact-echo methods for safety diagnosis of civil engineering and building structures. There are testing cases for the three models having one-dimensional form ; The first case is the measurement of thickness change of the model, the second is the detection of cavity in the model, and the third is the predictions of the lining thickness and the position of the cavity under tunnel lining condition.

• Clinical and Experimental Reproductive Medicine
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• v.49 no.1
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• pp.70-73
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• 2022

Objective: This study was conducted to assess the efficacy of subcutaneous granulocyte colony-stimulating factor (G-CSF) for treating thin endometrium. Methods: Data from 88 infertile women with thin endometrium (<7 mm) aged 23 to 40 years were evaluated retrospectively over a period of 1 year. In group 1, subcutaneous infusion of G-CSF (300 ㎍/mL) was administered to 44 women along with other supplemental treatments. If the lining did not exceed 7 mm within 72 hours, a second infusion was administered. In group 2, which also had 44 women, only estradiol valerate and sildenafil were administered, while subcutaneous G-CSF infusion was not. Embryo transfers were performed once the lining exceeded 7.5 mm. The efficacy of G-CSF was evaluated by assessing the thickness of the endometrium before embryo transfer, pregnancy rates, and clinical pregnancy rates. Results: There were no differences between the groups regarding demographic variables, egg reserves, sperm parameters, the number of embryos transferred, and embryo quality. The pregnancy rate was significantly higher in group 1 (60%, 24 of 40 cases) than in group 2 (31%, 9 of 29 cases) (p<0.001). The clinical pregnancy rate was also significantly higher in group 1 (55%) than in group 2 (24%) (p<0.001). Conclusion: Subcutaneous G-CSF infusion improved the thickness of the endometrium when it was thin. To the best of our knowledge, this is the first documented study to clearly demonstrate the benefits of subcutaneous G-CSF infusion for treating thin endometrium.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.9
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• pp.3797-3822
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• 2020

The inspection of cracks on the surface of tunnel linings is a common method of evaluate the condition of the tunnel. In particular, determining the thickness and shape of a crack is important because it indicates the external forces applied to the tunnel and the current condition of the concrete structure. Recently, several automatic crack detection methods have been proposed to identify cracks using captured tunnel lining images. These methods apply an image-segmentation mechanism with well-annotated datasets. However, generating the ground truths requires many resources, and the small proportion of cracks in the images cause a class-imbalance problem. A weakly annotated dataset is generated to reduce resource consumption and avoid the class-imbalance problem. However, the use of the dataset results in a large number of false positives and requires post-processing for accurate crack detection. To overcome these issues, we propose a crack detection method using a ternary classifier. The proposed method significantly reduces the false positive rate, and the performance (as measured by the F1 score) is improved by 0.33 compared to previous methods. These results demonstrate the effectiveness of the proposed method.

• Journal of the Korean Society of Clothing and Textiles
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• v.13 no.4
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• pp.388-399
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• 1989

The purpose of this study was to investigate the effects of garment design, fabric type and the presence of lining on the thermal insulation value $(I_{cle}\;and\;I{cl})$ and clothing area factor $(f_{cl})$ of skirts. A standing, electrically heated thermal maninkin was used to measure the insultation value of eighty skirts-five skirt styles with eight different fabrics, with and without lining. The air temperature of the chamber was set at $22.2^{\circ}C{\pm}0.5^{\circ}C$ , air velocity was limited to less than 0.1 m/s, and relative humidity was approximately $50\%$. The results are as follows: 1) The Ic, values of gathered skirt and flared skirt, which had high $f_{cl}$ values, were significantly higher than those of other skirts, though the highest $I_{cle}$ value among five styles wer pegged skirt. 2) Insulation values of various skirts were more relevant with physical properties such as thickness, air permeability, and thermal transmission of the materials rather than fiber content. 3) The addition of lining made significant difference in the insulation values of skirts and the differences of gathered and flared skirt were significantly higher than those of othere types of skirts.

• Journal of the Society of Naval Architects of Korea
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• v.44 no.6
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• pp.666-674
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• 2007

It is very important to estimate static squeezing pressure distributions for lining material of sterntube after bearing at dry dock stage since the maximum squeezing pressure value can be one of the significant characteristics representing coming navigation performances of the propulsion system. Moderate oil film pressure between lining material and propulsion shaft is also essential for safe ship service. In this paper, Hertz contact theory is explained to derive static squeezing pressure. Reynolds equation simplified from Navier-Stokes equation is centrally differentiated to numerically obtain dynamic oil film pressures. New shaft alignment technology of nonlinear elastic multi-support bearing elements is also used in order to obtain external forces acting on lining material of bearing. For 300K DWT class VLCC with synthetic bush of sterntube after bearing, static squeezing pressures are calculated using derived external forces and Hertz contact theory. Optimum partial slope of the after bush is presented by parametric shaft alignment analyses. Dynamic oil film pressures are comparatively evaluated for partially bored and unbored after bush. Finally it is proved that the partial slope can drastically reduce oil film pressure during engine running.