Air-tightness

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Air Tightness Control of Passenger Car Wheels

Air Tightness Control of Passenger Car Wheels

The assumption that by painting the leakage rate of wheels will be decreased is correct but it is important that the air tightness of a wheel does not change under operational usage. Otherwise it is found during investigations that the wheels ap- proved in unpainted state (leakage rate lower than allowable) have not satisfied the requirement after painting; this was influenced by manufacturing steps after the leakage test on unpainted wheel, which include chemical and thermical treat- ment of the wheel up to temperatures of 240˚C, which can generate a change of the microstructure and open some porosities. Based on the results of the pre- sented investigations and taking into account that the air tightness control on painted wheels save costs and time (not necessary to clean the wheel twice, after machining before helium gas testing and again before painting) and decrease the amount of waste due to the cleaning and due to it the ecological impact on envi- ronment, the testing of the wheel tightness after painting is better option. Test- ing of painted wheels as the finished product is fulfilling furthermore better the product liability requirements.

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Air tightness field data for dwellings in Ireland

Air tightness field data for dwellings in Ireland

1991, 88% of which was built prior to 1980 when minimum insulation standards were implemented [12]. These energy inefficient houses fall well below the current building regulations requirements and offer the good potential for energy savings from retrofitting. This study focuses on the quantitative data gathered from 28 occupied single family residential semi-detached and terrace houses, which combined make up the largest proportion of the 1.46 million dwellings in Ireland, 27.3% and 17.6% respectively [12]. Chan [10] found that US dwelling air-tightness can be normalised according to year of construction and divided the database into four broad age categories. This study adopted a similar approach, grouping the dwellings in three categories, based on year of construction, as shown in Table 1. The buildings studied and are of similar construction type; dwellings have two-storeys, three bedrooms, slab-on-grade floors, load bearing external cavity walls and cold roof construction. The average floor area and volume of the studied houses was 80m 2 and 202m 3 , respectively. Natural ventilation is provided by passive wall vents designed with closable hit and miss or permanently open louvered vent grilles in each room. However, many of the pre- 1975 houses have no wall vents.

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Improving The Air Tightness Of An Early 20th Century House

Improving The Air Tightness Of An Early 20th Century House

3 times improvement in airtightness following building works including: new windows and doors with draught proofing, sealing of suspended timber ground floors and repair to plaster defects around window frames in a scheme of 1930-1950s houses in the UK [21]. Hong et al. (2004) using a model methodology indicates that cavity wall insulation, loft insulation and draught stripping reduces infiltration rates by 24% and the reduction increases to 37% and 47% if the suspended floor and chimney are sealed [22]. Hall et al. (2013), also using a modelling methodology to investigate retrofit improvements in a replica of 1930’s-1960’s semi-detached houses in the UK, observed that enhanced draught-proofing gave a small reduction in air change hours (ACH) from 0.68-0.47; sealing around service penetration, closing vents and insulating the void beneath the suspended floor resulted in a further reduction to 0.41ACH and sealing the suspended timber floor to 0.25ACH [23].

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Effectiveness of draught reduction measures at improving building air tightness

Effectiveness of draught reduction measures at improving building air tightness

Stripping the windows and doors yielded small improvements in air flow leakage typically 1-3%. Despite many of these readings being within the margin of error of the measuring equipment, they all show a consistent downward trend. Furthermore, these results agree with Stephens (1998) who attributed 2% of building leakage rates to window and door surrounds [12]. The main exception to the small improvement in window draught stripping are the original timber windows in Case Study 5 which had a large number of openings and were noted by the owners as being particularly leaky. This indicates that these elements can, in certain circumstances, significantly contribute to building air leakage.

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Investigation of indoor air qality and the identification of influential factors at primary schools in the North of China

Investigation of indoor air qality and the identification of influential factors at primary schools in the North of China

Without heating provided to the classrooms, the indoor temperature is dynamic and primarily determined by four factors: heat loss from the fabric, air infiltration, heat gains from indoor heat sources (lighting and metabolic), and solar radiation. The classrooms measured had the same orientation and number of students. The lights were turned off during the measurement periods. It is a reasonable assumption to say that the insulation and air tightness were the two main factors determining the indoor air temperature. It is seen from Figure 7 that School B had the highest indoor temperature, since it was built in 2015 to comply with the new requirements for building insulation and air tightness.

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Lecablock, an Alternative Construction  Material for the Exterior Walls of  Passive House

Lecablock, an Alternative Construction Material for the Exterior Walls of Passive House

Air tightness is a building physical property that affects air movement in and through the building envelope. This air movement through cracks, openings, leaks in the building envelope affect heat and moisture flow in building [14]. Consequently, a passive house design requires high thermal insulation, high air-tightness with ex- cellent indoor air quality through efficient ventilation system in both winter and summer. For this study, the fan pressurization including blower door system [15] is the method used for measuring air tightness of the building envelope. In this method, the air tightness involves a depressurising a building to a pressure difference of 50 Pa. As the pressure differential reaches 50 Pa, the air leakage rate or permeability of the external envelope of the building can be evaluated. The Swedish requirement for the air leakage rate of passive house is 0.3 l/sm 2 [16] while the passive house institute (PHI) suggests an air exchange rate, n 50 = 0.6 hr −1 , in order to consider a build-

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Reliability   of the Repairing of Double Wall Containment Vessels in the Context of Leak   Tightness Assessment (M264)

Reliability of the Repairing of Double Wall Containment Vessels in the Context of Leak Tightness Assessment (M264)

A probabilistic framework has been developed to assess the design of a composite liner which is used in order to restore the air tightness of concrete containment vessels of French 1300 MWe power units. The liner is design by computing the “tensile stress area” around the material hatch area under pressurization of the vessel. Then the probability that tensile stresses (and possibly crack openings) appear outside this covered region is computed.

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Effects of Creativity and Cluster Tightness on Short Text Clustering Performance

Effects of Creativity and Cluster Tightness on Short Text Clustering Performance

6.1 Descriptive Statistics for Tightness Two pieces contribute to cluster tightness: the dataset itself and the choice of similarity metric. To illustrate, we represent each text with the vector for its similarity metric—for instance, the sum of its word2vec vectors or the unigram tf-idf vector— and reduce it to two dimensions using linear dis- criminant analysis. We plot five randomly selected gold standard clusters. Plots for unigram tf-idf and word2vec representations of PAS and CLUE are shown in Figures 1 and 2. These support the in- tuition that semantics-based similarity metrics are not as tightly clustered as n-gram-based metrics. Note also that the CLUE unigram tf-idf clusters appear tighter than the PAS unigram tf-idf clus- ters.

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Anomalous weak values and contextuality: Robustness, tightness, and imaginary parts

Anomalous weak values and contextuality: Robustness, tightness, and imaginary parts

Notice that the tightness of the inequality proven in Lemma 1 does not automatically imply that the inequalities in The- orems 1–3 are tight, because Eqs. (B7)–(B9) are stronger constraints than Eq. (B1) with the relevant value of ˜ p. Since Eqs. (B7) and (B8) reflect an infinite number of operational equivalences (one for each value of x), for Theorems 1 and 2 this issue cannot be straightforwardly settled using the tech- niques from [14] alone because those only apply to finite sets of equivalences. It may be possible to gain some confidence by using a series of increasingly fine-grained but nevertheless finite operational equivalences. Theorem 3 is a somewhat easier case: since it is intended to apply to a finite number of outcomes, for each number of outcomes there will in fact be a finite set of equivalences for which the relevant polytope could be calculated. In this work we leave the tightness of the inequalities in Theorems 1–3 as open problems, but we find the tightness of the inequality in Lemma 1 quite suggestive. APPENDIX C: PROOF OF THEOREM 4 (PLUS EXTENSION

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A PROPOSED NOVEL INHIBITOR STRETCHING PROCEDURE FOR POSTERIOR SHOULDER TIGHTNESS

A PROPOSED NOVEL INHIBITOR STRETCHING PROCEDURE FOR POSTERIOR SHOULDER TIGHTNESS

Background: Posterior shoulder tightness has been proposed to contribute to or cause a myriad of shoulder conditions. The tightness of the posteroinferior capsule and the teres minor and infraspinatus muscles of the posterior cuff has been hypothesized to cause osteokinematic [e.g., limited glenohumeral (GH) internal rotation] and arthrokinematic dysfunctions (e.g., decentralization of the humeral head). A number of interventions have been successful in the restoration of or at least improvement in posterior shoulder flexibility including joint mobilizations (e.g., posterior glide) and posterior cuff stretches. The two most common posterior cuff stretches, the sleeper stretch and the cross- body stretch, mimic the position of two common impingement Orthopaedic provocation tests. Despite the success of stretching to help optimize tissue extensibility to help prevent injuries, these stretches have been reported to cause pain in some symptomatic subjects. For these reasons, the authors propose creating an alternate posterior shoulder self- stretching technique that facilitates the inhibition of the target region.

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Train and Test Tightness of LP Relaxations in Structured Prediction

Train and Test Tightness of LP Relaxations in Structured Prediction

Structured prediction is used in areas including computer vision and natural language processing to predict structured outputs such as segmentations or parse trees. In these settings, prediction is performed by MAP inference or, equivalently, by solving an integer linear program. Because of the complex scoring functions required to obtain accurate predictions, both learning and inference typically require the use of approximate solvers. We propose a theoretical explanation for the striking observation that approximations based on linear programming (LP) relaxations are often tight (exact) on real-world instances. In particular, we show that learning with LP relaxed inference encourages integrality of training instances, and that this training tightness generalizes to test data.

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Country Contact Tightness Influence  Analysis Using Indirect Effects

Country Contact Tightness Influence Analysis Using Indirect Effects

Currently, some of the views for China’s international status are emphasis on the total amount of China’s GDP, as well as some pessimistic view of the status quo view of China, the lack of quality of China’s economic de- velopment and sustainability. With the China into WTO, China’s economy is melting into the world economy. In order to maximize the real reflects of China’s international status, we now select the “economic ties tightness” [1] and “close political ties” [2] as the inquiry is currently China’s economic clout and political influence of the two indicators. Topics in this article as “the analysis based on indirect effects of China’s influence”, is as used herein, economic and political influence to a brief description.

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Application of the Tightness Continuum Measure to Chinese Information Retrieval

Application of the Tightness Continuum Measure to Chinese Information Retrieval

We propose a novel approach to segmentation for Chinese IR which is based on the tight- ness measure. Our segmenter revises the out- put of a general segmenter according to the tight- ness of units. The intuition behind our method is that segmentation based on tightness of units will lead to better IR performance. For exam- ple, keeping “d d d d” (Pinatubo) as a unit should lead to better results than segmenting it into “d(skin) |d(include) |d(picture) |d(large)”. On the other hand, segmenting the compositional phrase “dddd” (Kuwait country) into “dd d(Kuwait) |d(country)” can improve recall. We revise an initial segmentation in two steps: first, we combine components that should not have been separated, such as “dddd” (Pinatubo); second, we split units which are compositional, such as “dddd” (Kuwait country).

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A Continuum-Based Approach for Tightness Analysis of Chinese Semantic Units

A Continuum-Based Approach for Tightness Analysis of Chinese Semantic Units

The result shows more similarity between the automatic ranking using our approach and the man- ual ranking as compared to the ranking using MI, which provides evidence that our method mea- sures the tightness of Chinese strings in a reasonable way. MI ranks collocations such as “ dd d d ” (maternity and child care) high, i.e. very tight, even higher than the transliteration “ ddd d ” (Malaysia), while our method ranks the former lower than the latter. The Chinese Gigaword corpus obtains the lowest similarity, which we believe is simply because it is small relative to the size of the documents indexed by the search engines, so is consistent with the general intuition about the emergent accuracy of simple statistics applied to large data sets.

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Investigating the Construct Validity of Perceived Cultural Tightness and Culture Strength

Investigating the Construct Validity of Perceived Cultural Tightness and Culture Strength

incomplete. Of the three heterogeneity measures, only RF (β = .55) was a strong predictor of PCT. RF contributed significant explanatory power to the model (F (3, 37) = 7.25, p<.01), leading to a change in R 2 of .30. Interestingly, although ELF was not a significant predictor upon its initial entry (Step 2), it became so with the inclusion of RF (and owing to a decline in the standard error of its value from .34 to .29). The restricted statistical power of these analyses should be noted; beta weights were of moderate level for each parameter (Table 23). However, none of the three measures significantly predicted societal culture strength, as measured by either practices or values (Table 24 and Table 25). Thus, it was not necessary to test for the mediation hypothesis. Furthermore, the positive relationship between RF and PCT indicates that a high degree of religious heterogeneity is predictive of cultural tightness, a somewhat surprising result. This result provides further evidence that the cultural tightness construct needs further conceptual development. Likewise, heterogeneity does not appear to be the complicating factor it was hypothesized to be. Clearly, ethnic and religious pluralism are not equivalent (see Table 22). Disregarding the problems with cultural tightness

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Principal Longevity, Leadership Behaviors, and Student Academic Achievement

Principal Longevity, Leadership Behaviors, and Student Academic Achievement

The results of this study and previous research 14-16, 32 suggest that the ROM deficits associated with posterior shoulder tightness are responsive to conservative therapeutic interventions. In fact, the internal rotation gains of +12 o observed within the ‘ISTM and stretch’ group are comparable to 4-6 week stretching programs ranging from +12-15 o . 14-16 In contrast, Laudner et al 11 examined the acute gains in internal rotation for healthy baseball players following a single bout of sleeper stretching. The authors report fewer internal rotation (+3 o ) gains compared to our results, however, players did not specifically display baseline internal rotation deficits. Furthermore, we combined the use of sleeper and cross-body adduction stretching, which resulted a longer total end range time (4 minutes versus 1.5 minutes). These differences in player

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The COMBINED EFFECT OF ANTI PRONATION TAPING AND GASTRO-SOLEUS COMPLEX STRETCHING ON FLEXIBLE FLAT FOOT

The COMBINED EFFECT OF ANTI PRONATION TAPING AND GASTRO-SOLEUS COMPLEX STRETCHING ON FLEXIBLE FLAT FOOT

Purpose – Muscle imbalance is one of the leading factor causing collapse of the foot arch such as dysfunction of tibialis posterior muscle and tendon which causes tightness of gastroc-soleus complex. Literature background suggests physiotherapy techniques that concentrate shoe modifications, taping and strengthening of intrinsic musculature of the foot. However, the factors such as tight extrinsic muscles of foot that include gastroc-soleus complex are neglected and hence need to be concentrated along with conventional treatment. The objective of the study is to evaluate the combined effect of anti-pronation taping and gastroc-soleus complex stretching in subjects with flexible flat foot.

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Evidence on Tightness in the Irish Labour Market  ESRI WP131  October 2002

Evidence on Tightness in the Irish Labour Market ESRI WP131 October 2002

The objective of this paper is to examine a variety of evidence on labour market tightening in Ireland. The paper was motivated by the need to bring together a variety of sources on how constrained the Irish labour market is becoming partly because of the mounting anecdotal evidence. The fact for example that firms and sectors (e.g. building and construction), are recruiting abroad indicates that the domestic supply of labour has become scarce. Furthermore recruitment fairs are being held in Europe and in North America in order to encourage people to migrate to Ireland so as to ease pressures on the labour supply front. The degree of tightness in the labour market is also highly visible in most urban areas, simply by the number of help wanted signs in shop windows, and by measures introduced by some large retailers to recruit older workers. The paper is structured as follow, section two reviews the performance of the labour market in recent years. Section three looks at the IBEC- ESRI monthly survey of industry, while section four examines other additional sources of information on a tightening labour market. Section five discusses the relationship between unemployment an vacancy rates and section six concludes.

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Characteristics of  Packings for Stuffing Boxes for the Proof of Strength, Function and Tightness  of Valves

Characteristics of Packings for Stuffing Boxes for the Proof of Strength, Function and Tightness of Valves

The operational safety of whole industrial plants is depending amongst others on the reliable function and tightness of valves. Therefore the sealing element stuffing box with packing is of great importance. For a suitable design of valves distinct characteristics of packings for stuffing boxes are required, describing the deformation, relaxation, friction, and tightness behaviour. These characteristics are defined and the testing procedures for their experimental determination are developed. Exemplary results lighten the typical and different performance of varied packing materials. Extensive characterisation of the materials mostly in use is subject of present testing programmes. Further on some ideas of topics for future research work are presented.

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Lexical Tightness and Text Complexity

Lexical Tightness and Text Complexity

We present a computational notion of Lexical Tightness that measures global cohesion of con- tent words in a text. Lexical tightness represents the degree to which a text tends to use words that are highly inter-associated in the language. We demonstrate the utility of this measure for estimating text complexity as measured by US school grade level designations of texts. Lexical tightness strongly correlates with grade level in a collection of expertly rated reading materials. Lexical tightness captures aspects of prose complexity that are not covered by classic read- ability indexes, especially for literary texts. We also present initial findings on the utility of this measure for automated estimation of complex- ity for poetry.

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