# Development of Cost and Schedule Data Integration Algorithm Based on Big Data Technology
## 4 Big Data Algorithm for Integrated Cost-Schedule Data Management  
### Data Structure for Cost-Schedule Integration  
This research establishes a framework for cost-schedule data integration in line with the identified requirement in Section 3.3. The data framework is established by extending the CIDF model proposed by [PERSON] et al. [4] since it allows flexible and dynamic data fusion. Cost and schedule management is a series of operating activities while asking fundamental questions continuously--\"Who did which work in which location with what construction method?\", \"How much has it done?\", and \"When has it done?\" The 5W1H data structure can be a tool to understand the questions by standardizing data into six dimensions (Where, What, How, When, Who, and Why) and combining the dimensions at different levels according to the need [29]. Two construction classification standards are applied to this research. UniFormat (Level 2-5) [30] is used as a benchmark for information units in the _WHAT_ dimension as it is an element-oriented classification system for cost estimation. In the _HOW_ dimension, the LOD of each information unit is defined based on MasterFormat (Level 1-5) [31], which is an operation-oriented system and widely used for specifications of construction contract documents. The conceptual data structure based on the 5W1H schema is illustrated in Figure 2.  
The _WHAT_ dimension indicates physical or functional elements (i.e., building components, systems). Construction project data commonly comprises the sum of physical elements, together with other information items linked to its own units. In this context, this dimension provides a basic information unit in the proposed structure. Based on the UniFormat, physical elements in this research are decomposed into four LODs: Major Group (Uniform Level 2) > Sub-Group (Uniform Level 3) > Element (Uniform Level 4) > Element Detail (Uniform Level 5). The _WHERE_ dimension represents space/zone classification data. It provides specifications of locations where construction activities happen using physical breakdown structures. The location of every element in the _WHAT_ dimension can be defined by using six LODs: Project > Sub-Project > Facility > Vertical > Horizontal > Space. Figure 2: Data Framework for Integrated Cost-Schedule Management, **(a)** the 5W1H Data Schema (adopted from [PERSON] et al. [4]), **(b)** Data Cube Facet Structure of the 5W1H Data Schema. The _HOW_ dimension expresses construction activities/operations required to generate physical elements. It describes construction methods comprising activities and provides linkage to basic cost elements and organization, such as productivity rate, unit material, unit labor. Based on MasterFormat, information units are be decomposed into five LODs: Work (Masterformat Level 1) \(>\) Work Section (Masterformat Level 2) \(>\) Division (Masterformat Level 3) \(>\) Operation (Masterformat Level 4) \(>\) Activity (Masterformat Level 5). The _WHEN_ dimension organizes time information, such as a completion duration of each work item related to quantity. As a major resource of schedule control, it is divided into eight LODs: Year \(>\) Quarter \(>\) Month \(>\) Week \(>\) Planned Early Start Time (EST) \(>\) Planned Early Finish Time (EFT) \(>\) Actual EST \(>\) actual EFT. The _WHO_ dimension defines responsible organizations for each activity in the _HOW_ dimension on elements in the _WHAT_ dimension. The project organization is classified into six LODs: Contractor \(>\) Work Crew \(>\) Individual \(>\) Management Corporation \(>\) Management Organization \(>\) Manager. The _WHY_ dimension addresses data required for specifying detailed information of each work item in the _HOW_ dimension. The dimension is utilized to distinguish items from the database, such as materials supplied by an owner, works completed by a special construction method, materials carried by a crane, and required equipment. The dimension is not mandatory but optional.