Partially decoupling and collar bonding of the encapsulated rebar rockbolts to improve their performance in seismic prone deep underground excavations

Rockbolt is widely employed all over the world as an effective ground reinforcement element in order to secure the underground workplaces.Ordinary encapsulated rebar or rebar rockbolt is most popular and commonly used as reinforcement in a ground support system because of its accessibility,cost effectiveness and easy practicability.Reinforcement elements in a seismic condition such as rock burst have to dissipate the energy release of the dynamic impact via their deformation and ultimate load capacity,knowing that the former is more important.In other words,achieving early stiff behaviour along with large deformation capacity in rockbolts are the goals for new development in rock reinforcement.Yielding rockbolts are expensive while some of them have large deformation capability with low ultimate load capacity.In this paper,modifications were made on encapsulation of rebar rockbolts to utilise it effectively as a yielding reinforcement in seismic conditions.Applying a sufficient decoupled length in the shank of rebar rockbolts which industry has regularly been using to control the bulking of the stress fractured ground,improves the deformation capacity of the bolt.Additionally,leaving a collar bonding underneath of the bearing pad and plate removes the weaknesses of the head anchorage of rockbolt.Therefore the dynamic performance of the bolt is improved by these easily applicable modifications.The behaviour and performance of encapsulated rockbolts have been discussed first,then the effects of modifications are illustrated.The proposed modification of the rebars is not only cost effective but also easy to apply in the field and improves the performance of reinforcements in seismic prone zones.

Study on the Mathematic Model of Apparel Lapel Collar Pattern

Fabrics of different thickness were selected and made into notch lapels in the experiment. The variation between the outside and inside lapel patterns after the lapel being folded was observed and measured. Besides,many factors leading to the variation were analyzed. Then the relation between fold angle and fabric thickness,and the variation of fabric thickness were obtained. The experimental results prove that the biggest horizontal variation between the outside lapel and inside lapel is at the breast line,and when the measuring point is above (or below) the breast line level,the farther it is away from the level,the smaller the variation becomes. In addition,conclusions can be drawn that the thicker the fabric is,the bigger the curve variation will be,and there is a certain mathematic relation between them.

Study on the Application of Turndown Collar Pattern

The relation between lining collar and face collar in the collar pattern designed by experiments and theoretical calculation is elucidated. In spite of the same constructions, the collar's shape and the fabric's thickness influence on the pattern of lining collar and the face collar, especially on the back center of the Iining and the two collar angles. The thicker the fabric, the more, with a proportional relation, the total variation. It is supposed that this work has made some contribution to the collar pattern design.

Study on the Application of Standing Collar Pattern

The relations between the lining collar and the face collar in pattern design of standing collar by experiments and theoretical calculation is elucidated. The collar's shape and the fabric thickness, although with the same construction, influence the lining collar and the face collar, especially the back center of the lining and the two collar angles. With a proportional relation, the thicker the fabric is, the more the total variation is. It is supposed to have some practical value to the collar pattern design, as well as to the fashion CAD.

Inter-individual variation in provisioning rate,prey size and number,and links to total prey biomass delivered to nestlings in the Collared Flycatcher(Ficedula albicollis)

Background:In bird species where offspring growth and survival rely on parents’food provisioning,parents can maximise their fitness by increasing the quantity and/or the quality of preys delivered to their offspring.Many studies have focused on inter-individual variation in feeding rate,yet this measure may not accurately reflect the total amount of food(i.e.energy)provided by parents if there is large variation in the quantity and quality of preys at each feeding.Here,we explored the relative role of individual(sex,age,body condition),breeding(hatching date,brood size)and environmental(temperature)factors on feeding rate,prey number,size and quality,and their contribution to total prey biomass delivered to the nestlings of 164 Collared Flycatcher(Ficedula albicollis)parents in 98 nests.Results:Preys delivered to the nest were mainly larvae(53.6%)and flying insects(45.6%).Feeding rate increased with brood size and age,and was higher in males than females.Mean prey number decreased,but mean prey size increased,as the season progressed and parents feeding their brood with primary larvae brought more preys per visit.Relationships between feeding rate,mean prey number and size remained when taking into account the provision-ing quality:parents brought either a large number of small prey or a small number of larger items,and the force of the trade-offs between feeding rate and mean prey number and size depended on the quality of the provisioning of the parents.Whatever the percentage of larvae among preys in the provisioning,the variance in total prey biomass was foremost explained by feeding rate(65.1%to 76.6%)compared to mean prey number(16.4%to 26%)and prey size(2.7%to 4%).Conclusions:Our study shows that variation in feeding rate,prey number,size,but not quality(i.e.percentage of lar-vae),were influenced by individual factors(sex and age)and breeding decisions(brood size and timing of breeding)and that,whatever the provisioning strategy adopted,feeding rate was the best proxy of the total biomass delivered to the nestlings.

Genetic diversity in Japanese populations of the Eurasian Collared Dove

Background:Eurasian Collared Dove(Streptopelia decaocto)is a species distributed in the Eurasian continent and North Africa,and inhabiting mainly in Saitama Prefecture in Japan.Eurasian Collared Dove is one of the most prosper-ous invaders in the world,and Japanese Eurasian Collared Dove has also been introduced from overseas.The Japa-nese population has declined to one-hundredth over 30 years and is being protected.In this study,we analyzed its genetic diversity in order to understand the genetic differences between wild populations of Eurasian Collared Dove and those bred in zoos.Methods:A sequence of about 1.9 kb mtDNA was determined for 20 wild Eurasian Collared Doves living in Saitama,Japan and 20 zoo-bred Eurasian Collared Doves,and population genetic analysis was performed.Results:In the COI gene,778 bp had the same sequence in all the 40 individuals examined,and no mutation sites could be confirmed.In the control region,two base substitution sites were confirmed in 1140 bp long sequence.Three haplotypes were detected in 20 individuals in wild,whereas all 20 zoo-bred individuals possessed the same haplotypes possessed in the wild population.Conclusion:Haplotypes of zoo-bred individuals were also retained among the wild individuals,confirming that no genetic problems could occur if the zoo-bred individuals were released to the wild for the Japanese Eurasian Collared Dove propagation program.

White Collar:The Middle Classes

White Collar:The American Middle Classes is a famous book written by Mills,C.Wright.In this book,Mills gave a description of the emergence of a"new class",the white-collar workers,during that age in US.He also mentioned about their life styles and their political consciousness.This thesis is to compare the different definitions of middle class in China and in US,and comment on the life styles and the political consciousness of the white collars in China.

嵌套网格技术中的Collar网格和虚拟网格方法

针对嵌套网格技术中的结合部问题,提出了Collar网格和虚拟网格方法.用双曲型微分方程生成的处于结合部的有两个边界分别处于不同固定曲面上的Collar网格,在保证计算网格的生成方便快捷而且网格质量高的前提下,解决了为物体结合部的内外边界点提供有效插值单元的问题.虚拟网格为紧贴物面的面网格,它的作用是将物面边界条件传递给其它网格的边界面,而其本身不作流场计算.计算实践表明,将Collar网格和虚拟网格结合起来应用在嵌套网格技术中能保证几何外形不发生变化,有效地处理各种复杂组合体外形的结合部问题.

Collar网格的生成及其在嵌合体技术中的应用

本文应用双曲型方程生成表面网格和空间网格的方法生成Collar网格 ,并将Col lar网格应用到嵌合体技术中 ,在保证计算网格的生成方便快捷而且网格质量高的前提下 ,有效地解决了为物体结合部的内外边界点寻找插值单元的问题。经数值计算验证 ,用本文方法求解有结合部的复杂组合体绕流可以得到精确可靠的数值结果。

Isolation and Identification of Fungus Causing Collar Rot Disease of Rubber Tree

Collar rot caused the death of Hevea rubber in a village located in Jino County of Xishuangbanna in September, 2012. In order to elucidate the causal agent of collar rot and its taxonomic status, the causal fungus was isolated and identified through a series of tests about its pathogenicity, morphology, culture feature and biological characteristics. The results indicated that the fungus was Fusarium venfrico- sum. It could grow at temperatures ranging from 10 to 40 ℃, and the most suitable temperature was 30 ℃. Its mycelium growth was inhibited above 40 ℃ or below 10 ℃. The accumulated water in wet season was the main reason for this disease occurrence.

Notes on the forest soil respiration measurement by a Li-6400 system

The correct method used in forest soil respiration measurement by Li-6400 is a premise of data quality control. According to the study in a larch plantation, collars should be inserted at 12 hours in advance to efficiently reduce the influence of CO2 spring-out.Moreover, collar insertion depth substantially affected soil respiration measurement, i.e. when collar was shallowly inserted into soil,transversal gas diffusion and the CO2 re-spring-out caused by unstable collars in the measurement could lead to overestimating soil respiration rate; however, when collar was deeply inserted into soil, root respiration decline caused by root-cut and the most active respiratory of the surface soil separated by the inserted collars could lead to underestimating soil respiration rate. Furthermore, an error less than 5% could be guaranteed in typical sunny day if the target [CO2] was set to the mean value of ambient [CO2] in most time of the day, but it should be carefully set in early morning and late afternoon according to changing ambient [CO2]. This protocol of measurement is useful in real measurement.

Centrifugal Casting of High Speed Steel/Nodular Cast Iron Compound Roll Collar

The centrifugal casting of compound HSS/nodular cast iron roll collar was studied,and the factors affecting transition zone quality were analyzed.The pouring temperature and interval in pouring are the main factors affecting transition zone quality.By controlling process parameter and flux adding during casting,high quality roll collar was obtained.The cause,why in the casting of HSS part,segregation appears easily,was analyzed and the countermeasure eliminating segregation was put forward,the measure eliminating heat treatment crackling was also put forward.

Effect of trapezoidal collars as a scour countermeasure around wing-wall abutments

Local scour around bridge abutments is a widespread problem that can result in structural failure. Collars can be used as a countermeasure to reduce the scour depth. In this study, the temporal scour development around a wing-wall abutment was investigated with and without collars. The tests were carried out under clear-water conditions for different abutment lengths, with collars of different sizes placed at the bed level. When no collar was used in the experiments, 70% of the maximum scour depth occurred in less than 2 h. However, when a collar with a width greater than the length of the abutment was used, no scour was observed for up to 200 min from the beginning of the experiments. The results show that an increase in the collar width not only led to a lag time for the onset of scouring but also reduced the maximum scour depth. Moreover, an increased collar width led to a better performance in mitigating scouring around smaller abutments. Generally, the scour depth decreased by 9%-37% with different collar widths.

Hydrodynamic Analysis of Elastic Floating Collars in Random Waves

As the main load-bearing component of fish cages, the floating collar supports the whole cage and undergoes large deformations. In this paper, a mathematical method is developed to study the motions and elastic deformations of elastic floating collars in random waves. The irregular wave is simulated by the random phase method and the statistical approach and Fourier transfer are applied to analyze the elastic response in both time and frequency domains. The governing equations of motions are established by Newton＇s second law, and the governing equations of deformations are obtained based on curved beam theory and modal superposition method. In order to validate the numerical model of the floating collar attacked by random waves, a series of physical model tests are conducted. Good relationship between numerical simulation and experimental observations is obtained. The numerical results indicate that the transfer function of out-of-plane and in-plane deformations increase with the increasing of wave frequency. In the frequency range between 0.6 Hz and 1.1 Hz, a linear relationship exists between the wave elevations and the deformations. The average phase difference between the wave elevation and out-of-plane deformation is 60° with waves leading and the phase between the wave elevation and in-plane deformation is 10° with waves lagging. In addition, the effect of fish net on the elastic response is analyzed. The results suggest that the deformation of the floating collar with fish net is a little larger than that without net.

The effect of fertilization on early growth of konara oak and Japanese zelkova seedlings planted in a harvested pitch pine plantation

We determined a suitable amount of fertilizer for konara oak（Quercus serrata） and Japanese zelkova（Zelkova serrata） planted in a harvested pitch pine（Pinus rigida） plantation. Two-year-old bare-root seedlings of konara oak and one-year-old containerized seedlings of Japanese zelkova were planted in April 2011. Three plots were established for each tree species to evaluate each of three fertilization applications. Solid compound fertilizer（N：P：K = 3：4：1） was applied yearly in three amounts（control： no fertilization, F1： 180 kg ha-1, and F2：360 kg ha-1）, every May from 2011 to 2013. We measured the root collar diameter and height, and analyzed the compartmental N and P concentrations. Compartmental N concentrations of konara oak and Japanese zelkova were not consistent based on amount of fertilization. However,the compartmental P concentrations of konara oak and Japanese zelkova were significantly different in the order of F2, F1, and control. Although the differences in growth of konara oak appeared after 3 years of fertilization,Japanese zelkova showed differences after only 2 years of fertilization owing to differences in seedling type. Growth of konara oak was affected by fertilization at F1 and F2 in2013. However, growth of Japanese zelkova was affected only at F2. Nutrient demand of Japanese zelkova appeard to be higher than that of konara oak, at least during the early growing period. Results from this study could be practically used in harvested pitch pine plantations to determine appropriate fertilization regimes.

环颈蝠 (Thainycteris aureocollaris) 在中国分布的再发现

福建省位于我国东南沿海,亚热带气候和丰富植被为野生动物的生存和繁衍提供了良好的生态环境(丁晖等,2015)。武夷山位于福建北部,地理位置独特,雨量充足,植被多样且茂密,是众多动物赖以生存的场所,丰富的生物多样性资源使其成为世界著名的动物模式标本产地(罗桂环等,2016;耿宝荣等,2020),其中翼手目中模式产地为武夷山挂墩的有皮氏菊头蝠福建亚种(Rhinolophus pearsoni chinensis)、大菊头蝠福建亚种(R.luctus calduelli)、斑蝠华南亚种(Scotomanes ornatus sinensis)和中管鼻蝠福建亚种(Murina huttoni rubella)4种,占福建现有蝙蝠种数(42种)的9.5%(陈友铃等,2009)。

Conversion Excess Coal Gas to Dimethyl Ether in Steel Works

The centrifugal casting of compound HSS/nodular cast iron roll collar was studied, and the factors affecting transition zone quality were analyzed. The pouring temperature and interval in pouring are the main factors affecting transition zone quality. By controlling process parameter and flux adding during casting, high quality roll collar was obtained. The cause, why in the casting of HSS part, segregation appears easily, was analyzed and the countermeasure eliminating segregation was put forward, the measure eliminating heat treatment crackling was also put forward.

Reinforcement Method of the Tubular Joints under Combined Loads Based on ANSYS Software

The jacket offshore platform structures working in the environment are subjected to various external conditions,such as wave loads,wind loads and corrosion of sea water.Therefore,the research on reinforcement of tubular joints has great practical value for the safety of offshore platforms.In this article,the finite element(FE)models of T-type tubular joint(T-joint)and K-type tubular joint(K-joint)are established by ANSYS software.Triangular rib reinforcement and collar plate reinforcement are used to reinforce the tubular joints.The reinforcement effects are assessed through the ultimate bearing capacity,and the influences of parameters of the rib and the collar plate on the ultimate capacity are analyzed.Besides,the effects of the two reinforcement methods are compared under the combined loads,and the results show that the reinforcement of the ribbed plate is more effective in resisting the deformation caused by bending moment,while the reinforcement of the collar plate is more effective to avoid the plastic damage caused by the axial pressure.

Three-dimensional Simulation and Pattern Making of Collar Using Geometric Model

An algorithm is presented for computationally simulating collars and drafting patterns. The collar shape was modeled by three-dimensional Bezier patch. Changing the position of consol points of the patch can interactively control the collar shape. Using triangular surface developing method, patterns of various styles of stand collar and separating collar were drafted. As the subsystem of 3D apparel design system, an interactive collar design system is constructed. To inspect the practical usage, we reproduced the collars using these patterns drafted by the interactive collar design system.Comparing with simulated collars, the system demonstrated well and we found it is more reliable and accurate than the method of handwork.

Influence of Different Geomorphic Surfaces and Profile Modification on the Growth of <i>Maesopsis eminni</i>(Engl) at the Yongka Western Highlands Research Garden Park Nkwen-Bamenda, North West Cameroon

The growth of Maesopsis under the influence of various geomorphic surfaces was followed within a period of 70 months. Young plants of two months old were transplanted into 70 × 70 × 70 cm holes under natural conditions (no inputs such as manure and other amendments). A randomized complete block design was set up for the experiment, alongside a control, and growth parameters followed (height and collar circumference). Three blocks with different geomorphic surfaces were put in place for the experiment (upper slope or block 1, middle slope or block 2 and foot slope or block 3). Results of the experiment indicated that geomorphic surface had a significant effect on height but not on collar circumference. Plant height increased progressively from upper slope to foot slope;less tall trees were found at the upper slope, while the tallest trees were found at the foot slope. After 70 months, maximum average height attained by plants for the experiment was 1228.3 cm, observed in block 3 (foot slope), significant at 0.05 confidence level with respect to geomorphic surface. In blocks 1 and 2 (upper slope and middle slope), maximum average heights attained were 798.5 and 937.5 cm, respectively and were shown to be statistically equal at 0.05 confidence level. Geomorphic surface had no effect on collar circumference. Maximum average collar circumferences attained after 70 months were 62.8 cm (observed at the upper slope), 61.3 cm (observed at the middle slope) and 76.3 cm (observed at the foot slope) and the various collar circumferences were shown to be statistically the same at 0.05 confidence level. For the control, maximum height attained after 70 months was 1240 cm (observed at the foot slope). At the upper slope and middle slope, maximum average heights were respectively, 800 cm and 905 cm, and were statistically equal at the 0.05 confidence level but different from the foot slope value of 1240 cm. Maximum average collar circumference was observed at the foot slope (76.3 cm), while circumferences of 62.8 cm and 61.3 cm were respectively observed at the upper and middle slopes. In the control, collar circumference was shown to be statistically equal at the upper and middle slopes but different from that at the foot slope at 0.05 confidence level. Correlations between growth parameters were more explained for the control than for the experiment. Increasing plant height was associated with decreasing percent slope (at a p-value of 0.05) corresponding to increasing soil depth favoring root exploration and soil and water retention. Profile modification enhanced plant growth and enabled the cultivation of trees on all geomorphic surfaces.