Modal parameter identification and damping ratio estimation from the full-scale measurements of a typical Tibetan wooden structure

Tibetan heritage buildings have a high historical and cultural value. They have endured adverse environmental loadings over hundreds of years without significant damage. However, there are few reports on their structural characteristics under normal environmental loadings and their behavior under dynamic loadings. In this research, a typical Tibetan wooden wall-frame building is selected to study its dynamic characteristics. Field measurements of the structure were conducted under environmental excitation to collect acceleration responses. The stochastic subspace identification （SSI） method was adopted to calculate the structural modal parameters and obtain the out-of-plane vibration characteristics of the slab and frames. The results indicated that the wall-frame structure had a lower out-of-plane stiffness and greater in-plane stiffness due to the presence of stone walls. Due to poor identified damping ratio estimates from the SSI method, a method based on the variance upper bound was proposed to complement the existing variance lower bound method for estimating the modal damping ratio to address the significant damping variability obtained from different points and measurements. The feasibility of the proposed method was illustrated with the measured data from the floor slab of the structure. The variance lower and upper bound methods both provided consistent results compared to those from the traditional SSI method.

The Effect of Soaking with Wooden Ash and Malting upon Some Nutritional Properties of Sorghum Flour Used for Impeke,a Traditional Burundian Malt-Based Sorghum Beverage

The objective of the present work was to determine the effect of wooden ash extract on anti-nutritional factors and to assess the effect of soaking with malting on nutritional properties of sorghum flour used for impeke. The addition of wooden ash extract during 24 h of soaking resulted in significant decrease in tannin by 50.2% and the decrease was observed to be progressive as malting time increases. 5 d of malting resulted in significant decrease in tannin by 69.3% and in phytic acid by 66.4% with slight decrease in ash, lipid, fiber, and starch. Malting showed an increased percentage of protein, essential amino acids, and then in vitro protein digestibility were markedly improved with increasing malting time. Sugars analysis proved a significant increase in maltose, glucose, fructose, and structural analysis of sorghum starch displayed porosity on granule＇s surface susceptible to the amylolysis.

A feasibility study of using two-component polyurethane adhesive in constructing wooden structures

This investigation was conducted to determine the feasibility of using a two-component polyurethane （PUR） adhesive, with special waterproof properties, in constructing wooden structures. We designed and conducted tests to compare the shear strength and adhesion performance of PUR with polyvinyl acetate （PVAc） adhesive on block-shear specimens constructed of oriental beech （Fagus orientalis L.）, fir （Abies alba Mill.）, poplar （Populus deltoides Bartr.）, white oak （Quercus alba L.）, sycamore （Platanus orientalis L.） and white walnut （Juglans cinerea L.）. The values of the percentage of wood failure were also determined in specimens constructed with each adhesive. The highest shear strength values of both adhesives were obtained in specimens constructed of beech, while the lowest shear strength values were obtained in fir and poplar specimens. Average shear strength of the PUR adhesive was 16.5% higher than that of the PVAc adhesive. Specimens constructed of fir, poplar and sycamore were characterised by the highest percentages of wood failure, whereas the lowest average percentages of wood failure were obtained in beech and oak specimens. With the exception of oak specimens, there was no statistically significant difference between percentage of wood failure among the PUR and PVAc adhesives. Generally, the PUR adhesive showed an acceptable adhesion performance on wood materials used in our study.

Dominant changes in the breast muscle lipid profiles of broiler chickens with wooden breast syndrome revealed by lipidomics analyses

Background: Chicken is the most consumed meat worldwide and the industry has been facing challenging myopathies. Wooden breast(WB), which is often accompanied by white striping(WS), is a serious myopathy adversely affecting meat quality of breast muscles. The underlying lipid metabolic mechanism of WB affected broilers is not fully understood.Results: A total of 150 chickens of a white-feathered, fast-growing pure line were raised and used for the selection of WB, WB + WS and control chickens. The lipids of the breast muscle, liver, and serum from different chickens were extracted and measured using ultra performance liquid chromatography(UPLC) plus Q-Exactive Orbitrap tandem mass spectrometry. In the breast, 560 lipid molecules were identified. Compared to controls, 225/225 of 560 lipid molecules(40.2%) were identified with differential abundance(DA), including 92/100 significantly increased neutral lipids and 107/98 decreased phospholipids in the WB/WB + WS groups, respectively. The content of monounsaturated fatty acids(MUFA) was significantly higher, and the polyunsaturated fatty acids(PUFA) and saturated fatty acids(SFA) were significantly lower in the affected breasts. In the liver, 434 lipid molecules were identified, and 39/61 DA lipid molecules(6.7%/14.1%) were detected in the WB and WB + WS groups, respectively. In the serum, a total of 529 lipid molecules were identified and 4/44 DA lipid molecules(0.8%/8.3%) were detected in WB and WB + WS group, respectively. Compared to controls, the content of MUFAs in the serum and breast of the WB + WS group were both significantly increased, and the content of SFAs in two tissues were both significantly decreased. Only five lipid molecules were consistently increased in both liver and serum in WB + WS group.Conclusions: We have found for the first time that the dominant lipid profile alterations occurred in the affected breast muscle. The relative abundance of 40.2% of lipid molecules were changed and is characteristic of increased neutral lipids and decreased phospholipids in the affected breasts. Minor changes of lipid profiles in the liver and serum of the affected groups were founded. Comprehensive analysis of body lipid metabolism indicated that the abnormal lipid profile of WB breast may be independent of the liver metabolism.

Research on Technology of Wooden Furniture CAD System

This paper introduces the current situation of domestic furniture production as well as world furniture CAD products, puts forward the necessity of developing a dedicated CADsystem——WFCAD and its main functions. It analyzes in detail the applied technology and keytechniques, including geometric modeling, assembly, joint design, database linking and management. The application of WFCAD in furniture manufacturing enterprises and its further improvement are outlined.

Intraorbital wooden foreign bodies: case series and literature review

Intraorbital wooden foreign bodies(IOWFBs) constitute a relatively rare ocular trauma, which occupy a special type of intraorbital foreign bodies(IOFBs). Data regarding IOWFBs must be obtained from case reports or small case series due to their rarity. Here, we reported 5 cases of IOWFBs and reviewed the related literatures, which could provide comprehensive information regarding the clinical manifestations, diagnosis, and surgical treatment of IOWFBs. Combined with the published literature, a total of 51 independent cases were counted after we added 5 cases. Among them, the number of male and female patients was 35 and 16 respectively;the mean age was 27.3±18.2(range 1-66)y. Obviously, the disorder seemed to occur mainly in young and middle-aged people. Because of the diversity in the clinical manifestations and imaging characteristics of IOWFBs, misdiagnosis and missed diagnosis often occur during the initial visit. Delayed diagnosis may lead to a high risk of orbital infection caused by IOWFBs. Surgery is the treatment of choice for most patients;however, the missed diagnosis and residue of foreign bodies after previous surgery cannot be ignored. Therefore, an accurate diagnosis is governed by the detailed trauma history, careful ocular examination, close observation of clinical manifestations, correct imaging diagnosis [e.g., magnetic resonance imaging(MRI) or computerized tomography(CT)], and timely and completely elimination of IOWFBs.

Landscapes of Folk Beliefs Embodied by Wooden Arch Bridges in East Fujian,China

Cultures of folk beliefs in east Fujian Province were introduced and folk beliefs in the local area summarized as ancestor worship,female immortal worship,Taoist secular gods worship,nature worship and local sage worship.Distribution of wooden arch bridges in east Fujian was introduced,major functions of the wooden arch bridges summarized as traffic hub,repairing village environment,creating rural areas with a favorable Fengshui environment,and also god temple.Folk beliefs embodied in wooden arch bridges were classified and responsibilities of the gods and immortals introduced.It was summarized that wooden arch bridges in east Fujian were embodied with diversified folk beliefs,most of the gods and immortals were believed to be responsible for practical aspects of the locals' life,many gods and immortals were worshipped together,which shows the inclusiveness of folk beliefs in the local area,and contributes to main connotations and regional features of local folk belief cultures.

Wooden Wall Construction of Traditional Miao Stilted Buildings: A Case Study of Xijiang Miao Village in Guizhou

Wooden walls of traditional stilted buildings of Miao Nationality show outstanding regional characteristics. Taking the well-preserved traditional stilted buildings in Xijiang Miao Village for example, this paper focused on the construction units of the wooden wall, and the hierarchy of wooden wall construction, concluded spatial forms of the wooden wall, in order to explore the indigenous construction culture in the wooden wall system, protect and inherit the culture; seek for the ways of expressing national and regional characteristics in the modern architectural designs of relevant cultural regions.

Spatial Interpretation of the Wooden Arch Gallery Bridges in Northeast Fujian from the Perspective of Behavior Space

On the basis of investigating wooden arch gallery bridges in China,perspectives of researchers studying wooden arch gallery bridges in northeast Fujian Province were reviewed,and the innovativeness of researches from the perspectives of cultural geography and significance of wooden arch gallery bridge for the locals’behaviors was proposed.Youxi Village in Qinyang Town,Shouning County,known as the Village of Gallery Bridge,was taken for example to analyze physical,spiritual and social properties of its wooden arch gallery bridge spaces.Wooden arch gallery bridge is an effective boundary point of settlement space,constituting natural ecological spaces and man-made physical spaces of rural settlements.And as a type of building space,wooden arch gallery bridge expands settlement spaces,contributes to settlement cultures,and enriches spiritual connotations of regional cultures.In northeast Fujian,wooden arch gallery bridge is an important social space for the locals’daily life by carrying on living,production and spiritual functions.

Heritage and Development of Ningbo Bone-Inlaid Wooden Works

Bone-inlaid wooden art is a very old artistic form that has a strong artistic appeal and local flavor. It can be traced back to the Longshan Culture in the late Neolithic Age, and becomes mature in the late Qing Dynasty. As time lapses, however, bone-inlaid wooden art is gradually out of sight. It was not until June 2008 when Ningbo bone-inlaid wooden art was included in the "second batch of national intangible cultural heritage protection list" that it once again caused social concern. Ningbo bone-inlaid wooden art has a long history, and its craftsmanship is complex. Many bone-inlaid wooden works in Ningbo have been damaged more or less. Therefore, workers in the field of heritage protection should undertake a more systematic protection and repair work based on scientific research, making contributions to the heritage and development of intangible cultural heritage.

Wooden foreign body impalement through the right shoulder region–an unusual penetrating injury:A case report

BACKGROUND Impalement of the body is a rare injury and comes with varied presentation.There is no set classification or defined protocols for managing this injury.This case report aims to create awareness among trauma surgeons about unusual presentation and management of such case.CASE SUMMARY A 45-year-old man presented to the emergency department with a sharp penetrating wooden plank at right clavicular region between the neck and shoulder following a road traffic accident.The vehicle had crashed into a roadside wooden hut,thus causing an impalement injury.He was meticulously worked up and taken to emergency theatre.The wooden plank was removed and the wound healed uneventfully.Postoperatively,he had fairly good shoulder function and was able to return back to work successfully.CONCLUSION Each impalement injury brings in challenges in management as no two cases are the same.The varied presentation and risks involved should be known to medical professionals handling the emergency.Coordinated multidisciplinary team approach is needed for successful outcome.

Construction Techniques of Wooden Dwelling Column Frame in Tibetan Regions of Yunnan Province, China

Column frame of folk dwellings with slope roof in Tibetan regions of Yunnan Province was studied. Through field investigation and surveying, column frame timber, main components and construction techniques were introduced. The research showed that column frame of slope-roof dwelling in Tibetan regions of Yunnan is a regional construction technique using timber as the major materials, tenon-and-mortise work as the major connection, characterized by excellent structural expandability, and shock resistance, but it has no quantitative technical support. Scientific and systemic study is needed to improve safeness and livability of local dwellings.

Residential Wooden Houses Built in Small Towns of Lublin Region in 1918-1939

The housing situation just after the First World War was very bad.This was due,among other things,to the huge war damage of buildings as well as years of neglecting the construction movement during 123 years of partitioning.Not only public buildings were destroyed,but most of all housing development,which at that time in the Lublin region mostly had a wooden structure.The article presents a part of a comprehensive study of the wooden architecture of the interwar period of small towns in the Lublin region.Representative examples from each type of object were discussed.

Development of a Hybrid Pin Joint with a Compressed Wooden Dowel and Metal Pipe

A newly developed hybrid pin (HP), composed of a compressed wooden dowel inserted into a stainless steel pipe is suggested in this research. This configuration is expected to grant high stiffness by bending performance of the metal pipe and rich ductility through shear deformation of compressed wooden dowel without brittle split of the joint member. Experimental tests were performed in order to verify your assumptions and pursue an optimum design. Double shear test perpendicular to the grain of HP was conducted with parameter of thickness and loading direction for base member for pin’s diameter. Rotational test for mortise and tenon joint inserted with HP was performed in order to evaluate the moment resisting performance. Consequently, the hybrid pin showed satisfactory performance as shear type fastener by virtues of not only relatively high stiffness but also rich ductility originated from the properties of each component, stain less steel pipe and compressed wood.

A Case Study of VäxjöMunicipality’s Actions to Increase the Construction of Wooden Multi-family Buildings

Sweden has a housing shortage,which the Swedish authorities expect to continue until 2025.Producers of wooden multi-family houses have a relatively small market share in comparison to traditional building materials.The limited capability to fulfil the increased building demand also restricts the possibilities for development towards innovation,bio-economy and sustainability.The municipalities in Sweden have responsible for planning of the building development in their region based on their projected requirements and strategies.Combining this with a desire to develop sustainable building solutions based on wood increases the complexity.Currently,public building developments are achieved through the public procurement act or the land allocation activity,dependent on their development strategy.This normally involves the development of local strategies regarding,e.g.design,material choice and geographical development.By identifying market drivers enables improved market entry activities related to public building initiatives using wood-based solutions.Hence,by improving transparency in the land allocation activity generate enhanced possibilities for the companies to respond successfully to the requests submitted by the municipalities.This knowledge is used to better understand the required strategic development for the companies,the government and the municipalities to increase the use of sustainable building materials in Swedish multi-family housing projects.

Reducing Greenhouse Gas Emissions through Improving the Life Span of Wooden Power Electric Poles of Eucalyptus saligna

The present work deals with reducing greenhouse gas emissions through improving the life span of wooden power electric poles of Eucalyptus saligna. Indeed, in Sub-Saharan African countries, Cameroon in particular, most of the power line networks are made of wooden supports and according to the Cameroon energy distribution company, wooden poles represent 32% of the causes of death linked to the state of the network. The company’s 2019 annual report indicates that 40,000 wooden poles were in critical condition and should be replaced. A significant number of mechanical failures affecting these supports have been observed. For example, on the HVA/LV power line “D17 Nko- abang” in Yaoundé in Cameroon, less than three years old, 10 (ten) cases of poles falling and/or breaking, due to their mechanical loading, were observed over a period of fewer than nine months, causing an average service stoppage for more than 11 hours and affecting an average of 3280 customers. These incidents lead to questions about how the supports are dimensioned and what load capacities they are designed to support. The aim of this work is, therefore, to suggest a method of dimensioning wooden poles hence reducing green- house gas emissions due to the deforestation by reducing the number of woo- den poles at risk to be replaced on Cameroon’s electricity distribution network. And more specifically, to reduce the number of mechanical failures affecting the wooden supports observed by analyzing the current wooden supports with their loads and to make proposals for improving the actual dimensioning me- thods. From the study carried out, it appears that 449 out of 845 supports, i.e., 53% needed to be replaced or monitored because they support the nominal forces ranging from 85% to 150% of their admissible limit and proposals have been made to improve their dimensioning.

Wooden Structures within the Context of Parametric Design: Pavilions and Seatings in Urban Landscape

Today,on the one hand,while the traditional design process continues,on the other hand,digital design systems along with advances in computer technologies continue to present designers with new and effective ideas.Parametric design is preferred by designers for its relationality,contributing toward versatility,ensuring flexibility,simplifying diversification,and for presenting programmatic solutions.As is seen in a number of areas,we have also begun to encounter the use of parametric designs produced with parametric design systems and wooden materials in urban landscaping.The purpose of this study is to examine the upper cover application and seating elements generated by taking advantage of parametric designs from wooden construction materials in urban landscaping areas,and examine the impact of wooden material characteristics while generating behavior and parametric structures of technologies.After researching parametric design and wooden material concepts,an attempt was made to reach conclusions through analyses conducted by examining parametric wooden designed pavilion and seating element specimens applied in various regions of the world.

Wooden Bowls in Zhongdian

Zhongdian,a smnall town in the Tibetan-irhabited area of Yumnan Province,is affec-tiorately referred to as the Town of Wooden Bowls.Local work-shope belonging to 39 families are mainty concentrated in Shangqiaotou and Yindao villages in Nid.They make about 20,000 wooden bowls a yeat.The craftspensons are local farm.ec who create thare ware during the off peason for agriculrure.

Improvement of thermal performance of envelopes for traditional wooden vernacular dwellings of Tujia Minority in Western Hunan,China

Thermal performance of envelopes and indoor thermal environment were technologically improved for traditional wooden vernacular dwellings of Tujia Minority in Western Hunan, China, on the premise of protecting their conventional styles. Thermal insulation boards and wooden boards were added to the interior side of external walls of vernacular dwellings to form two layers of air cavities, so as to gain excellent thermal performance. The indoor temperature of such dwellings after reconstruction was apparently improved compared with the data before reconstruction both in winter and summer, which verified the feasibility and the effectiveness of the reconstruction technologies proposed.

A Guide to Wooden Flooring

Based on standards,this book introduces all kinds of wooden flooring in a concise and conversa-tional manner.It talks about the characteristics of wooden flooring,qualitative