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Featured Application: In this article, we present a methodology for adapting pavement quality indexes for roads with gravel pavement. The findings presented in this article can be used to improve driving safety and gravel pavement maintenance. Gravel pavement has lower construction costs but poorer performance than asphalt surfaces on roads. It also emits dust and deforms under the impact of vehicle loads and ambient air factors; the resulting ripples and ruts constantly deepen, and therefore increase vehicle vibrations and fuel consumption, and reduce safe driving speed and comfort. In this study, existing pavement quality evaluation indexes are analysed, and a methodology for adapting them for roads with gravel pavement is proposed. We report the measured wave depth and length of gravel pavement profile using the straightedge method on a 160 m long road section at three stages of road utilization. The measured pavement elevation was processed according to ISO 8608, and the frequency response of a vehicle was investigated using simulations in MATLAB/Simulink. The international roughness index (IRI) analysis showed that a speed of 30–45 km/h instead of 80 km/h provided the objective results of the IRI calculation on the flexible pavement due to the decreasing velocity of a vehicle's unsprung mass on a more deteriorated road pavement state. The influence of the corrugation phenomenon of gravel pavement was explored, identifying specific driving safety and comfort cases. Finally, an increase in the dynamic load coefficient (DLC) at a low speed of 30 km/h on the most deteriorated pavement and a high speed of 90 km/h on the middle-quality pavement demonstrated the demand for timely gravel pavement maintenance and the complicated prediction of a safe driving speed for drivers. The main relevant objectives of this study are the adaptation of a road roughness indicator to gravel pavement, including the evaluation of vehicle dynamic responses at different speeds and pavement deterioration states. [ABSTRACT FROM AUTHOR]

In this study, it is aimed to design a learning trajectory that supports the conceptual infrastructure and dynamic ways of thinking in the process of basic geometric constructions of sixthgrade students and to examine the cognitive development of the students in this process. In this qualitative study, which is a design based research, data were collected through individual and group worksheets, video recordings of courses, field notes, homework sheets and clinical interviews with focus participants. The focus participants were determined by criterion sampling through an open-ended test developed for the concepts of point, line, line segment and ray, which were considered as prerequisites for the basic geometric constructions. The study was conducted in three phases which are preparation and design, teaching experiment and retrospective analysis. During the preparation and design phase, the initial hypothetical learning trajectory has been designed with the literature review performed to allow comprehensive analysis in epistemological and didactic aspects. Formative evaluations were made by micro analyzes during the teaching experiment carried out for the implementation and evaluation of the learning trajectory. Finally, comparative analysis was conducted on students' thinking processes and actions between the assumed learning trajectory and the actual learning trajectory. Consequently, the revised learning trajectory and students' developmental progress are presented in an interpretive framework. In the most general sense, supporting the cognitive actions such as realizing a construction in different ways and directions, taking into account the changing and unchanging aspects of the geometric structures during the construction process, interpreting the variability of the compass opening, revealing all of the possible points as a circle or part of the required points as an arc, making changes in the route of the steps and interpreting or defending these changes are important in building dynamic geometric constructions. It was noted that the students who could follow the algorithmic steps only operationally without making defense with mathematical justifications were able to put forward more static thinking processes. It was seen that learning environments limited only by analysis and construction phases might be insufficient in realizing constructions with strengthened conceptual infrastructure, and therefore, the importance of designing learning environments that provide opportunity for proof and discussion phases that support dynamic processes of thinking was revealed. In addition, it has been concluded that a learning trajectory which provides opportunity to take into consideration the characteristic features of the geometric structures in the constructions and to make connections with other structures or constructions makes important contributions in strengthening of the conceptual infrastructure. [ABSTRACT FROM AUTHOR]

Gravel pavement has lower construction costs but poorer performance than asphalt surfaces on roads. It also emits dust and deforms under the impact of vehicle loads and ambient air factors; the resulting ripples and ruts constantly deepen, and therefore increase vehicle vibrations and fuel consumption, and reduce safe driving speed and comfort. In this study, existing pavement quality evaluation indexes are analysed, and a methodology for adapting them for roads with gravel pavement is proposed. We report the measured wave depth and length of gravel pavement profile using the straightedge method on a 160 m long road section at three stages of road utilization. The measured pavement elevation was processed according to ISO 8608, and the frequency response of a vehicle was investigated using simulations in MATLAB/Simulink. The international roughness index (IRI) analysis showed that a speed of 30–45 km/h instead of 80 km/h provided the objective results of the IRI calculation on the flexible pavement due to the decreasing velocity of a vehicle’s unsprung mass on a more deteriorated road pavement state. The influence of the corrugation phenomenon of gravel pavement was explored, identifying specific driving safety and comfort cases. Finally, an increase in the dynamic load coefficient (DLC) at a low speed of 30 km/h on the most deteriorated pavement and a high speed of 90 km/h on the middle-quality pavement demonstrated the demand for timely gravel pavement maintenance and the complicated prediction of a safe driving speed for drivers. The main relevant objectives of this study are the adaptation of a road roughness indicator to gravel pavement, including the evaluation of vehicle dynamic responses at different speeds and pavement deterioration states.

This paper examined the sensitivity of 20 road unevenness indicators (RUIs) for local discontinuities (various distresses, joints, joint and surface defects, cracks, spalls, other road features, humps, dips, etc.) of a maximum length of 20 cm in Portland cement concrete pavements. Approximately, 5500 road records totalling 530 km from the Long-Term Pavement Performance programme were processed. Raw profiles were separated into random and distress components using a median filtering method. The median filter was set to identify distress of a maximum length of 20 cm and with a minimal height of 3 mm. Over 26,000 distresses and their dimensions were identified. Raw longitudinal road profiles were compared with the separated pure random components. The most sensitive indicators of distresses were road elevation spectrum parameters in whole- and short-wave bands, the Profile Index and the road elevation root mean square (RMS) value in the short-wave band. Negligible sensitivity was observed for the International Roughness Index, road elevation RMS values and spectrum parameters in long- and medium-wave bands. The influence of road data pre-processing on the results was estimated. [ABSTRACT FROM AUTHOR]

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In this paper, we present a formula in order to divide an angle into n-equal segments so that n could be any constructible real number on the interval, [2,1000], The actual Arc length of a unit circle is then approximated by this formula. A novel approximate drawing method by a new algorithm is given for the division of an angle by the Straightedge and Compass. Computations show good agreement between the actual length and the novel formula approximation. The presented method in this paper is compared with the well-known methods of multisecting angles. Constructible numbers have also been discussed in light of our current findings. [ABSTRACT FROM AUTHOR]

This article uses forty-four face-to-face interviews with individuals who formerly identified with straightedge-a clean-living, mostly youth-based (sub)culture-to explore the possible role chosen youth cultural identities play in adult transition, as well as extend recent work on aging and youth scenes by more deeply engaging both 'subjective adulthood' and the retrospective accounts of 'ex' members. Data show interviewees developing (paths to) subjective adulthoods substantially influenced by former affiliation with straightedge culture they frequently believe mark their (paths to) adulthoods fundamentally distinct from others in their age cohort. Particularly, individuals transitioning from straightedge recounted pronounced subculturally rooted antipathy toward adult conventionality, often envisioned alternative adult trajectories for themselves, discussed transitional impediments and opportunities they took to be unique to transitioning from straightedge, and, in indicating heightened awareness of adulthood's 'facework,' visualized a collective of others like them inside adult social spheres by virtue of the formative bases (former) scene affiliation provided them. Ultimately, findings suggest that the study of subjective adult transition may profit from directly considering the formative influence of elective youth identities. Likewise, perhaps the most fertile grounds in the turn toward examining aging and scenes might rest in meanings individuals attach to adulthood and transitioning, even for ex-members of certain communities. [ABSTRACT FROM AUTHOR]

The paper examined the sensitivity of nineteen road unevenness indicators (RUI) to the distresses (reflection cracks, transverse cracks) of the composite pavements. The simulated longitudinal road profiles with superimposed distresses were compared with the pure random part of profiles to estimate the difference in roughness. The influence of distress width, depth, density, and road data pre-processing (moving average base length and sampling interval) was estimated. Analysis of variance was provided to detect the significance of differences in estimated RUIs for distressed and random profiles. The most sensitive indicators to the presence of the reflection cracks were the root mean square (RMS) value in the short wave band, the road elevation spectrum parameters in the whole and short wave bands. A weak sensitivity was observed for the International Roughness Index (IRI), Ride Number (RN), Profilograph Index (PrI) or the road elevation RMS values in the long and medium wave bands. [ABSTRACT FROM AUTHOR]

This article explores the formation of Krishnacore, a phenomenon born from the amalgamation of American straightedge punk and the Hare Krishna Movement in the 1990s. It argues that whilst shared choices of lifestyle, such as vegetarianism and a distaste for intoxicants and illicit sex, were core tenets towards the conception of the scene, it was bhakti-yoga (the theological and philosophical basis of the Hare Krishna Movement) that cemented such a relationship. Furthermore, it also explores the aesthetic context of punk within a Vedic context, in particular with reference to what is termed as ‘Nada-Brahma', or the sacralisation of sound. [ABSTRACT FROM AUTHOR]

This study presents the regression relationships between two commonly used indicators of longitudinal road unevenness, the international roughness index (IRI) and the straightedge index. A total of 290 real longitudinal road-profile records were processed. The asphalt-concrete and cement-concrete road surfaces were analyzed separately. Five differently defined straightedge indexes, i.e., the deviations between straightedge and profiles, were considered. The one-parameter linear approximation without an absolute term seems to be an appropriate model for fitting the unevenness indexes relation. The conversion relationships between five differently defined straightedge indexes were derived. The results were calculated as a function of a straightedge length in the range of 3 to 7.8 m. The two-parameter power function was shown to be the most suitable approximation model of the straightedge indexes dependence on the straightedge length. The analyzed influence of the different slab lengths of cement-concrete profiles on the conversion relationships indicated the marginal impact for the typical slab lengths. [ABSTRACT FROM AUTHOR]

Straightedge is still widely adopted as a simple and reliable tool in pavement smoothness measurements, although rolling profilers have become more and more popular. If measured and interpreted correctly, the data collected with a straightedge is able to provide not only undulation depth but also profile wavelength. This study examines the basic features of measurements of roadway undulations with straightedges as well as the critical vibration frequencies for riding comfort. A universal gain curve is proposed to adjust measurements with various straightedges. A vehicle-pavement coupled system is formulated to find the natural frequencies of a vehicle, wheel axle, and pavement. The system also determines the wavelengths critical to riding comfort on roadways. Analysis with the coupled system shows that the vibrations critical to riding comfort may be magnified and transmitted through the wheel axle. The research suggests the suitable straightedge for specific wavelengths. The 3 meter straightedge is recommended on freeways with speed limits over 100 km/h, whereas the 1 meter straightedge is more suitable for urban streets to assure correct amplitudes of the critical waviness to riding comfort. Measurement interval is critical to the resolution of profile wavelengths. It is suggested that the measurement interval not exceed half of the critical wavelength. [ABSTRACT FROM AUTHOR]

We look at a new approach to mathematical constructions. Using GeoGebra, we first do dynamic analysis and exploration. Again with GeoGebra, we then do a strict compass and straightedge constructions. Finally and yet again with GeoGebra, we do dynamic testing and discussion of proof. In this paper, we work through a complete example of construction a triangle and discuss our results of using this method in the classroom. [ABSTRACT FROM AUTHOR]

This paper uses 20 in-depth interviews with individuals who formerly identified as straightedge to explore a largely overlooked but potentially important dimension of youth subcultures: life after subculture. Interviews illustrate the potential importance of life after subculture for gaining a fuller understanding of subculture and indicate that residue from former subcultural affiliation can be a marker of a group’s relative substance. Interviews additionally underscore problems with prevailing theoretical models of subculture and support the claim that approaches to and conceptions of subculture should attend to phenomenological levels of analysis and potentialities. [ABSTRACT FROM AUTHOR]

In this article, the author examines the relative roles of music and the internet for self-identifying members of the straightedge youth subculture. For nearly 30 years, subcultures have been conceptualized primarily in terms of music and style. Participation has therefore typically been characterized by the consumption of specific types of music and clothing and participation in local, face-to-face music scenes. However, with the recent growth of information and communication technologies like the internet, opportunities have emerged that enable individuals to participate in subcultures in which they otherwise might not participate. The author shows that a new type of subculturalist is emerging--one whose subcultural participation is limited to the internet. Using the concepts of authenticity and scene, the author explores how participants in a straightedge internet forum negotiate their affiliations with the subculture and how some members attempt to half others' claims to a straightedge identity. The study suggests that the internet is emerging as a new, but highly contested, subcultural scene. [ABSTRACT FROM AUTHOR]

Over the past 10 years, sociologists have attended to the impacts of the Internet on youth subcultural coalescence, display, identity, and resistance. In this article, the authors develop a critique of this body of work, describing how existing research places undue emphasis on young people `s experiences either online or offline and how a lack of consideration has been given to the ways that subcultural expressions are continuous across the apparent "virtual-real" divide. With the aim of addressing some of these concerns, the authors draw on ethnographic case studies of "Rave" and "Straightedge" to explore the impact of the two realities (i.e., online and offline realities) on understandings of subcultural experience in these youth formations and articulate how the theoretical split between the virtual and real in cyber-subcultural research does not accurately capture the lived experiences or identity negotiations of these youth. [ABSTRACT FROM AUTHOR]