"Non UBC"@en . "DSpace"@en . "Froese, T. M., Newton, L., Sadeghpour, F. & Vanier, D. J. (EDs.) (2015). Proceedings of ICSC15: The Canadian Society for Civil Engineering 5th International/11th Construction Specialty Conference, University of British Columbia, Vancouver, Canada. June 7-10."@en . "International Construction Specialty Conference (5th : 2015 : Vancouver, B.C.)"@en . "Canadian Society for Civil Engineering"@en . "Ardila, Fabian A."@en . "Francis, Adel"@en . "2015-05-26T20:38:44Z"@en . "2015-06"@en . "Graphical modeling is considered to be a suitable approach for displaying project data because of its ability to communicate information clearly and effectively through graphic means such as shapes, connectors, colours and textures. However, current methods and software do not propose a standard protocol for the graphical representation of the scheduling. Little research has been undertaken in this area and therefore, it has been up to the individual planner to set his or her own standard. We have developed the first phase of a new standard protocol for construction project scheduling compatible with Chronographical Modeling. This first phase consists of the development and validation of a graphic convention including textures and colours. The present paper discusses the validation phase of this convention. Its main objective is to validate a range of textures that represent the construction activities. This validation was performed through a case study with the participation of 15 planners, as well as graduate and undergraduate students. It consists of several tests including the application of the various textures of the proposed convention to a building scheduling. The results of the case study were used to assess the suitability of the protocol and its visual clarity while simultaneously seeking to diminish the mental effort necessary for finding information. Future phases are designed to integrate other graphic elements to the protocol, such as shapes, symbols and codes."@en . "https://circle.library.ubc.ca/rest/handle/2429/53507?expand=metadata"@en . "5th International/11thConstruction Specialty Conference 5eInternational/11eConf\u00C3\u00A9rence sp\u00C3\u00A9cialis\u00C3\u00A9e sur la construction Vancouver, British Columbia June8 to June 10, 2015 /8 juin au 10juin 2015 DESIGN AND VALIDATION OF THE FIRST PHASE OF THE NEW CHRONOGRAPHICAL STANDARD PROTOCOL FOR CONSTRUCTION PROJECT SCHEDULING Fabian A. Ardila1 and Adel Francis2, 3 1Department of Construction Engineering, \u00C3\u0089cole de technologie sup\u00C3\u00A9rieure (\u00C3\u0089ts), Canada 2Department of Construction Engineering, \u00C3\u0089cole de technologie sup\u00C3\u00A9rieure (\u00C3\u0089ts), Canada 3adel.francis@etsmtl.ca Abstract: Graphical modeling is considered to be a suitable approach for displaying project data because of its ability to communicate information clearly and effectively through graphic means such as shapes, connectors, colours and textures. However, current methods and software do not propose a standard protocol for the graphical representation of the scheduling. Little research has been undertaken in this area and therefore, it has been up to the individual planner to set his or her own standard. We have developed the first phase of a new standard protocol for construction project scheduling compatible with Chronographical Modeling. This first phase consists of the development and validation of a graphic convention including textures and colours. The present paper discusses the validation phase of this convention. Its main objective is to validate a range of textures that represent the construction activities. This validation was performed through a case study with the participation of 15 planners, as well as graduate and undergraduate students. It consists of several tests including the application of the various textures of the proposed convention to a building scheduling. The results of the case study were used to assess the suitability of the protocol and its visual clarity while simultaneously seeking to diminish the mental effort necessary for finding information. Future phases are designed to integrate other graphic elements to the protocol, such as shapes, symbols and codes. 1 INTRODUCTION Graphical modeling is considered to be a suitable approach for displaying project data because of its ability to communicate information clearly and effectively (Tory and Moller, 2004). However, little research has been undertaken within the domain of construction project planning to develop new approaches for the graphical modeling of non-linear project schedules. Indeed, Gantt charts combined with the precedence logic still dominate among visualization techniques, despite the fact that finding and monitoring information on the schedule can be difficult (Russell and Udaipurwala, 2002). In addition, current methods and planning software do not offer a graphic standard for schedule representation. Chronographical Modeling (Francis, 2004; 2013) addresses this issue with one of the specific goals being to propose a standard protocol for graphical representation of construction project planning. The first phase of this protocol involves the development and validation of a graphic convention of textures and colours representing construction activities, resources and locations which was then validated through a case study with the participation of 15 professionals, graduate and undergraduate 104-1 students from within the construction industry. The study included several tests and the application of the texture convention to a construction project schedule. The results allowed us to evaluate the intuitiveness, the suitability and the visual clarity of this convention. They also demonstrate that using of textures on a schedule aids with the data search process. 2 RESEARCH MOTIVATION Effective communication of information depends in large part upon the way that data is graphically represented and how we perceive and interpret this information. According to Encarnacao et al. (1994), the development of new visualization systems must take into account the following three approaches: \u00E2\u0080\u00A2 Technology-driven: what can be done with current technology; \u00E2\u0080\u00A2 Perception-driven: what makes sense considering the constraints on human visual; \u00E2\u0080\u00A2 Task-driven: what the user wants. Considerable effort has been put forth towards the Technology-driven approach, where advancements in terms of information technology are remarkable. However, little attention has been given to the Perception-driven and Task-driven approaches. Tory and Moller (2004) argue that it is necessary to think about how we analyze and interact with graphic variables and how it can affect the information visualization. Indeed, the brain is able to perceive multiple graphic elements simultaneously, but it cannot process them in parallel. Our vision focuses on small areas of the visual field and watches one element after another in an unintended sequence named \"Attention\" (Rodrigues et al., 2008). Ware (2013) divides the Attention process into three sub-processes: \u00E2\u0080\u00A2 The Pre-Attention Process: quick parallel process where one chooses the graphic elements to be analysed; \u00E2\u0080\u00A2 Visual Perception: slow series of processes where one analyses the graphic properties of the visual element comparing correspondence, differentiation, relationships, understanding and meaning; \u00E2\u0080\u00A2 Interpretation: process in which one interprets the analysed information and obtain results. Rodrigues et al. (2008) assure that the design of visualization systems should seek to maximize the impact on the pre-attentive process. According to these authors, textures and colours are among the graphic elements that encourage this. Bertin (1977) places texture third, right after colour, in terms of its effectiveness in the encoding of nominal information. Because of their separation properties, these graphic elements are extremely useful for encoding such information. Several areas have implemented graphic standards including colours and textures. For example, a standard manual of traffic signals was already in place in the infrastructure sector in 1935 (Hawkins, 1992). The geotechnical sector uses abbreviations, textures and colours to represent soil types according to ASTM D2487-11. Urban planning, somewhat related to the construction industry, has used a standard convention of colours for the classification of land use since 1965 (APA, 2013). However, current methods and existing planning software do not offer any standard for schedules. Chronographical Modelling (Francis, 2004; 2013) addresses this issue, with one of its goals being to propose a standard protocol for the graphical representation of construction project planning. 3 RELATED LITERATURE 3.1 Using textures Textures can be very effective for encoding information in construction schedules (Carrier-Fraser, Francis and McGuffin, 2013) since they favor data interpretation by association allowing for a search in parallel. Thus, the interpretation and learning processes are more easily carried out. However, their use has some limitations and must follow certain guidelines in order to facilitate the pre-attentive process. 104-2 Tufte (2001) and Wilkins et al. (1984) argue that streaked textures have very strong terminations and contrasts. This can cause visual discomfort and symptoms from simple fatigue to headaches. According to Healey (1999), a combined use of graphic variables such as colour and texture may not favor the pre-attentive process causing a move from a search in parallel to a search in series. Moreover, if the background brightness resembles the texture, the texture visualization will require more time and visual memory and thus be more difficult to interpret. According to Carrier-Fraser, Francis and McGuffin (2013), in order to stay within the pre-attentive process limits and ensure that the data search will be performed in parallel; the information represented by textures must be independent from that shown by colours. This facilitates the search for only one data type, but not both. The American National Standards Institute (ANSI) and the International Organization for Standardization (ISO) proposed standards for the use of textures. The BSI standards BS 8888 (2002) and BS 308-1 (1993) compile a set of guidelines for the use of hatching. Suggestions of hatching applicable to construction can be found in the standards BS 1192-3 (1987), BS 5930 (1999) and BS 8541-2 (2011). The National Institute of Building Science (NIBS) in collaboration with the American Institute of Architects (AIA) developed the US National CAD Standard or NCS (NIBS, 2005). This document compiles hatching, objects and symbols commonly used in Computer Aided Design. 3.2 Graphical modeling in construction projects planning Graphical modeling is not widespread in construction project planning. Tory et al. (2013) present a visual comparison tool for construction schedules. Their research addresses three main components: the graphical representation of constraint types (Echeverry, Ibbs and Kim, 1991; Koo, Fischer and Kunz, 2007), the interactive representation of precedence networks, and the comparison of different planning alternatives. Stott et al. (2005) were inspired by a subway system, representing the project planning using lines, colours and shapes. Aigner et al. (2005) propose a graphics system called Planning Lines to represent uncertainty in the time attributes of activities. This system also incorporates the concept of probability in time representing two values: the minimum and the maximum duration. The modeling approach of the Chronographic Method (Francis, 2013) studies the graphical representation of the project in the spatial dimension (Francis, 2004; Francis and Miresco, 2011). This approach proposes classifying all the elements that make up a building project into five entities (Table 1). Chronographical Modeling analyzes the visual interface, the graphic elements and the parameters associated with these elements. The goal is to establish a standard protocol for the graphical representation of construction project planning. Textures and colours are examples of graphic elements used by this protocol. Carrier-Fraser, Francis and McGuffin (2013) propose guidelines for the use of these graphics in modeling the physical entity. According to these authors, activities can be represented by textures, and colours can be linked to resources and locations. Table 1: Chronographic method entities (Francis, 2013, p. 192) Physical (PE) Associative (AE) Functional (FE) Scale (PE) Direction (DE)Activities / DeliverablesRelationships and constraintsDeterministic; Probabilistic et heuristicTime No axis (cyclic scales)Direct and indirect laboursHierarchical Fixed et variables CostSingle axisScaled, grouped or noneOperators / Haulers Grouping Optimisation QualityTwo axisScaled, grouped or nonePermanent materials Layering Decision % progressThree axisScaled, grouped or noneEmplacements Sheeting (Sub) Generalised PerformanceType of contract Attributes Risk104-3 4 PRESENTATION AND VALIDATION OF THE TEXTURE CONVENTION 4.1 Presentation of the texture convention According to Chronographical Modeling (Francis, 2013), activities can be represented by textures. Our texture convention aims to facilitate finding, interpreting and memorizing information on a construction schedule. The following approaches were taken into account in the development of this convention: \u00E2\u0080\u00A2 Prioritizing the use of standard graphics. \u00E2\u0080\u00A2 Using a minimum of graphic elements through a generic convention that adaptable to the needs of construction industry and to individual users. The texture convention includes two levels or layers in order to accommodate the demands of building projects. The base level of this convention represents construction divisions or summary activities. Several types of graphic elements were used to elaborate the textures on this level: hatching, objects, symbols, lines, shapes, and in some cases text. Most of these are standard elements (hatching, objects and symbols) that are listed in the US National CAD Standard (NIBS, 2005) and commonly used for the graphical representation of information in construction. In addition, the texture convention has been structured according to the divisions proposed by the MasterFormat Classification System (CSI, 2012). Furthermore, the US National CAD Standard (NCS) also uses MasterFormat as reference for classifying the information. The second level of this convention uses shapes and lines to represent building elements. These elements have a generic denomination which allows users to customize their application in order to adapt to the needs of each activity and each project. Figure 1A shows a 3D view of the convention levels and the information represented. Figure 1B is the result of the superposition of these levels within the same work plane. A. 3D view of the texture convention levels B. Plan view of the texture convention levels Figure 1: 3D and plan views of the texture convention levels 4.2 Validation of the texture convention We conducted a case study to validate our concepts and evaluate the achievement of our goals. The design and realization of this case study followed the steps recommended by Lam et al. (2012). These steps correspond to: i) setting a goal; ii) picking suitable scenarios; iii) considering applicable approaches; iv) creating evaluation design and planned analyses. Lam et al. (2012) also identified seven evaluation scenarios according to the methods commonly used in evaluation of information visualization, as follows: \u00E2\u0080\u00A2 EWP: Evaluating environments and work practices; \u00E2\u0080\u00A2 VDAR: Evaluating visual data analysis and reasoning; 104-4 \u00E2\u0080\u00A2 CTV: Evaluating communication through visualization; \u00E2\u0080\u00A2 CDA: Evaluating collaborative data analysis; \u00E2\u0080\u00A2 UP: Evaluating user performance; \u00E2\u0080\u00A2 UE: Evaluating user experience; \u00E2\u0080\u00A2 AEV: Automated evaluation of visualizations. Our case study has two parts: in the first part, we evaluate the visual data analysis and reasoning (VDAR) in order to assess the suitability of the texture convention and its visual clarity. In the second part, we evaluate communication through visualization (CTV) with the intention of validating if the texture convention helps to diminish the mental effort necessary for finding information on the construction schedule of a building. 4.2.1 Evaluating visual data analysis and reasoning This part of the case study evaluates the suitability of the texture convention and its visual clarity. It was conducted using a questionnaire consisting of eight questions. The first four questions tested the intuitiveness and simplicity of this convention. First, we asked participants to intuitively associate the meanings of the graphic elements presented in each question. The purpose of this exercise was to assess whether our texture convention could be understood intuitively and without any prior explanation. After each question, we presented the answer. Then we asked the participants to repeat the exercise again in order to evaluate the ease of memorization of this convention. Table 2 shows the success rate for questions 1 to 4. According to this table, more than half of the participants were able to intuitively identify the meaning of textures using hatching. Nearly 90% of the participants succeeded in memorising the meaning of these textures after knowing the answer. In the case of textures using objects and symbols, the results were lower compared with those of textures using hatching. While most of the objects and symbols used are listed in the NCS and are commonly associated with the proposed divisions, this result may be influenced by other factors such as occupation, specialty and overall experience of the participants. However, despite the results in terms of intuitiveness for this part of the texture convention, almost 70% of the participants were able to remember the meaning of textures after knowing the answer. Table 2: Success rate of question 1 to 4 regarding the texture convention Questions 5 to 8 aim to gather expert opinion about the meaning and graphic quality of the textures and graphics used. Participants had the opportunity to express their opinions and also offer suggestions for improvement. Table 3 shows the acceptance rate for the textures assessed in these questions. According to this table, the acceptance percentage is greater than 70% in most cases. Table 3: Acceptance rate of question 9 to 14 regarding the texture convention Figures 2 and 3 present our validated proposal for levels one and two of the texture convention. This proposal has taken into account the suggestions for improvement made by participants in the case study. Questions Evaluated topic Figure With knowing the answer Knowing the answer1 and 3 Textures using hatching 2A 56% 89%2 and 4 Textures using objects and symbols 2B 27% 67%42% 78%AverageQuestion Evaluated topic Figure Accepted Non accepted N.A.5 Textures using hatching 2A 72% 23% 5%6 Textures using objects and symbols 2b 62% 28% 10%7 Textures using lines and text 2C 71% 22% 7%8 Convention representing construction elements 3A 76% 21% 3%70% 24% 6%Average104-5 Figure 2A includes textures using hatching, while and Figure 2B presents textures using objects and symbols. Facility services are represented by lines and text (Figure 2C). Figure 2: Textures representing construction divisions or summary tasks Figure 3 shows the second level of this convention where shapes are used to represent the construction elements. Dotted lines are used to indicate a pre-construction stage; for example, the preparation and approval of workshop drawings. The straight lines indicate that the element is in construction. These elements have a generic denomination which allows users to customize their application in order to adapt to the needs of each activity and each project. Figure 3: Convention representing construction elements 104-6 4.2.2 Evaluating communication through visualization In this part of the case study, we applied the texture convention to the construction schedule of a building. This schedule presented the planning of the design and procurement stages, the construction of foundation, structure, finishes, facility systems and site works. Then participants in the study responded to 16 open questions regarding information that could be obtained from the prepared schedule. The schedule was presented as a Gantt chart and was available to participants in PDF format in order to avoid influencing their performance through the use of an unfamiliar method or planning software. Partipants could graphically interact with the schedule by performing simple actions, such as zooming in and out, and moving throughout schedule. Some information, such as names and durations of activities, was removed in order to ensure the use of the texture convention to obtain the requested information. To answer the questionnaire, participants had no prior training and had to use only the knowledge gained in responding to the questionnaire used in the previous section of case study (VDAR) as outlined above. They could work individually or in teams consisting of a maximum of three people. Table 4 presents the questions asked about the schedule using the texture convention and summarizes the results. Three people worked individually and twelve people worked in teams: i) two teams of three; and ii) three teams of two. Despite the fact that participants had to use only the knowledge acquired during the first part of the case study, almost 70% of the questions were resolved correctly. If we also consider the questions that had an approximate answer, the success rate reaches 84%. We also analyzed the impact of the use of teams on the results (Figure 4). The number of people per team does not appear to have had a significant impact in relation to the performance of the group. However, people working as a team were able to establish group discussions which positively influenced the accuracy of their responses compared with those who did so individually. Table 4: Success rate of questions regarding a construction schedule using the texture convention No. Question Correct Approx. Bad N. A.1How long does it take the procurement process?Note: the bidding is made after completion of the design phase88% 13% 0% 0%2 The preliminary studies (soil study) are included in the schedule? 63% 25% 0% 13%3Indicate the start and end date of the foundation constructionNote: do not take into consideration the workshop drawings50% 13% 38% 0%4Could you indicate if plumbing works are required before the construction of the slab-on-grade?63% 38% 0% 0%5 The foundation construction requires the installation of wood piles? 100% 0% 0% 0%6 The building structure is mostly made of concrete or steel? 75% 25% 0% 0%7 How many floors is the building? 50% 25% 25% 0%8Indicate the start and end date of the structure construction?Note: the structure starts with the ground floor beams and ends with the construction of metal stairs (non-structural metallic element), do not take into consideration the workshop drawings.13% 38% 50% 0%9 When does the interior finishing begin? 25% 13% 63% 0%10 How long does it take the installation of exterior doors and windows? 100% 0% 0% 0%11 How long does it take to finish the interior walls? 38% 13% 38% 13%12 The building will have an elevator? 100% 0% 0% 0%13Is it possible to delay the workshop drawings activities of HVAC without affecting the successors?100% 0% 0% 0%14Is it possible to delay the workshop drawings activities of Fire Suppression without affecting the successors?75% 25% 0% 0%15The plumbing fixtures requires the preliminary installation of furniture such as cabinets and countertops?63% 38% 0% 0%16 When it is scheduled to begin the earthworks and exterior improvements? 88% 0% 13% 0%68% 16% 14% 2%Average104-7 Figure 4: Success rate depending on team type 5 CONCLUSIONS AND FUTURE WORK The first phase of the new protocol for the graphical representation of construction project planning includes the development and validation of a texture and colour convention. The texture convention uses different graphic elements such as hatching, objects, symbols, lines and text to represent major construction divisions. This convention provides a second level of information through a convention of shapes and lines. Test results show the intuitiveness of this convention, with particular regard to textures using hatching. These tests also indicate that experts have a fairly positive perception in relation to the meaning and graphic quality of the textures and graphic elements used. These experts had the opportunity to propose suggestions for improvement which have helped to refine the initial concept. We also tested the texture convention in relation to the ease of finding information on a construction schedule where the activity names have been removed. Note that the participants had no prior training and no documentation was permitted. The results show that nearly 70% of the questions were resolved correctly. The success rate reaches 84% if we also consider the questions that had an approximate answer. The results have therefore validated both levels of this convention: the textures that represent major divisions and the convention representing construction elements. This demonstrates clearly that the use of textures and shapes helps simplify the information search process on a schedule. Future developments are planned with other graphic elements as well as a wider consultation regarding the validation and application of the texture convention on other types of projects. References Aigner, W., Miksch, S., Thurnher, B. and Biffl, S. 2005. PlanningLines: Novel glyphs for representing temporal uncertainties and their evaluation. Ninth International Conference on Information Visualisation. London, United Kingdom. IEEE, 457-463. APA. 2013. LBCS Background: http://www.planning.org/lbcs/background. 63% 69% 75% 23% 13% 13% 85% 81% 88% 0%20%40%60%80%100%One person Two persons Three personsCorrect answers Approximate answers Total104-8 Bertin, J. 1977. La graphique et le traitement graphique de l\u00E2\u0080\u0099information. Paris: Flammarion, 277 p. Carrier-Fraser, P., Francis, A. and McGuffin, M. J. 2013. Conception d\u00E2\u0080\u0099un protocole graphique des op\u00C3\u00A9rations de construction par l\u00E2\u0080\u0099utilisation des textures et des couleurs. 4e Conf\u00C3\u00A9rence sp\u00C3\u00A9cialis\u00C3\u00A9e sur la construction. Montreal, QC. CSCE, CON-188: 1-10. CSI. 2012. MasterFormat: http://www.csinet.org/Home-Page-Category/Formats/MasterFormat.aspx. Echeverry, D., Ibbs, C. W. and Kim, S. 1991. Sequencing knowledge for construction scheduling. Journal of Construction Engineering and Management, 117(1): 118-130. Encarnacao, J., Foley, J., Bryson, S., Feiner, S. K. and Gershon, N. 1994. 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M., Rodgers, P., Burkhard, R. A., Meier, M. and Smis, M. T. J. 2005. Automatic layout of project plans using a metro map metaphor. Ninth International Conference on Information Visualisation. London, United Kingdom. IEEE, 203-206. Tory, M., and Moller T. 2004. Human factors in visualization research. Transactions on Visualization and Computer Graphics, IEEE, 10(1): 72-84. Tory, M., Staub-French, S., Huang, D., Chang, Y.-L., Swindells, C. and Pottinger, R. 2013. Comparative visualization of construction schedules. Automation in Construction, Elsevier, 29: 68-82. Tufte, E. R. 2001. The Visual Display of Quantitative Information. 2nd Edition, Cheshire: Graphics Press, 197 p. Ware, C. 2013. Information visualization : perception for design. 3rd Edition, Boston: Morgan Kaufmann, 536 p. Wilkins, A., Nimmo-Smith, I., Tait, A., Mcmanus, C., Della-Sala, S., Tilley, A., Arnold, K., Barrie, M. and Scott, S. 1984. A Neurological basis for Visual Discomfort. Brain, 107(4): 989-1017. 104-9 "@en . "Conference Paper"@en . "10.14288/1.0076381"@en . "eng"@en . "Unreviewed"@en . "Vancouver : University of British Columbia Library"@en . "Attribution-NonCommercial-NoDerivs 2.5 Canada"@en . "http://creativecommons.org/licenses/by-nc-nd/2.5/ca/"@en . "Faculty"@en . "Other"@en . "Design and validation of the first phase of the new chronographical standard protocol for construction project scheduling"@en . "Text"@en . "http://hdl.handle.net/2429/53507"@en .