Workforce information database system to support production planning in construction projects.
Kim, Sang-Chul ; Kim, Yong-Woo
1. Introduction
Production planning spans from a master schedule to look-ahead and
weekly work plans. While a master schedule is used as a strategic
planning tool, the look-ahead and weekly work plans are used as
production planning tools (Ballard 2000). Many models (Adeli, Karim
1997; AbouRizk, Mather 1998; Sucur, Grobler 1996; Aalami 1998) suited
for developing a master schedule for a project and creating the list of
required activities have been developed, along with preferred precedence
relationships between activities under expected constraints. A large
number of computer tools have also been developed to assist project
managers in manually developing and maintaining a master schedule. They
function as tools for generating a common representation that depicts
predecessor relationships between activities where each activity has a
given duration and unit resources allocated to it. This representation
facilitates communication between different participants involved in a
construction project as to who should be doing which work and when.
However, these tools are inadequate when it comes to supporting
production planning, which in turn is the primary tool of personnel
performing construction work in the field. The productivity of field
workers depends mainly on the actual availability of resources and the
crew's actual capacity. Availability of resources is governed by
resource flow prior to installation, including the timely generation or
procurement, release or delivery, and allocation of their resources
(Tommelein, Ballard 1997; Choo 2003). The Last Planner System (LPS) and
relevant computer tools enables the production planning process to
ensure availability of resources on time by shielding uncertainties from
flowing into production units (Ballard et al. 2007; Kim et al. 2008a).
The capacity of crews or production units in production planning
needs to be updated as soon as information becomes available. In the
planning process, assigned loads and quantitative capacity are well
defined quantitatively through quantity takeoff and database estimation,
whereas a production unit's qualitative capacity could not be
easily tracked or managed. The performance quality of a certain
production unit can be defined using various qualitative attributes such
as the level of workmanship, accident history and experiences. The
capacity of crews or production units taking into account their
qualitative attributes is important in improving production plan
quality, but this information is hard to acquire in managing
construction projects.
In recent years, mobile computing technologies (MCT) such as
radio-frequency identification (RFID) and personal digital assistants
(PDA) are being adopted to transmit a variety of information among
project participants. Those technologies contributed to improving field
work, consequently reducing construction duration, defects, accidents
and wastes (Kimoto et al. 2005; Bowden et al. 2006). MCT can facilitate
the easy transmission of knowledge and expertise to field workers as
well as field information to management. With MCT, the information on
production units (e.g., qualitative attributes of production units)
could be easily collected and transmitted so that such information could
be updated and reflected in the production plan.
This paper proposes a method of developing and identifying
qualitative attributes to complement historic data-based quantitative
capacity, which helps improve the quality of the production planning
process. A prototype database system with the qualitative attributes of
production units is also presented to help production planners (i.e.,
project engineers or supervisors) match the capacity of production units
with workloads more efficiently. The research approach to this end can
be best explained by identifying the different research phases and tasks
as follows (Fig. 1).
The first phase of the research involved several rounds of
literature review and discussions with industry professionals. This
phase sought to understand current production planning practice in terms
of matching capacity and load and how mobile communication technology is
being utilized in construction projects.
The development of system architecture and prototype database
system is then examined. The research team conducted a survey to
identify major factors in determining a production unit's
qualitative capacity. The number of respondents was 136 practitioners.
After identifying needs (i.e., factors in workforce capacity), the
research team developed a workforce information database system
prototype coupled with MCT to collect, track, and manage workforce
information to be used in calculating capacity.
A pilot project for testing the proposed prototype system was
implemented. The pilot test demonstrated how the system can help field
engineers and site managers use quantitative and qualitative information
on loads and capacity in production planning. In order to validate the
proposed system's usability, a survey was performed on foremen,
superintendents, field engineers, and site managers. The potential
benefits from interpreting survey results were described in the
Discussion section.
[FIGURE 1 OMITTED]
2. Matching capacity and load production planning
Project planning techniques based on network models (such as CPM)
are currently accepted and applied. However, such project scheduling
techniques are not effective in managing production based on the
schedule (Choo 2003). Superintendents and foremen use some form of
production planning tool to execute their projects. In many cases, these
tools were neither systemized nor formalized. Production planning is the
most detailed planning process developed by foremen of contractors who
will actually carry out the work (Ballard 1994; Ballard, Howell 1998).
The production units (e.g., subcontractor) can provide knowledge
regarding: (1) development of creative solutions; (2) space needs; (3)
construction capacities; and (4) supplier's lead-times and
reliability (Gil et al. 2000). Production planning attempts to match
capacity and assignment load with optimal precision based on given
conditions (Ballard et al. 2007). Information regarding work force
capacity includes availability of labor, equipment, and tools. In terms
of labor, information includes the skill level, productivity, and
availability of each worker. However, such labor information is hard to
quantify and track, giving rise to problems in leveraging such
information in production planning (Choo 2003). A recent survey (Viana
et al. 2010) indicated that this lack of information is one of the
critical challenges encountered in implementing a production plan on
construction sites.
Matching load to capacity in a production planning system is
critical in determining productivity of the production units (Ballard,
Howell 1998; Ballard 2000), and is also integral to system cycle time,
the time required for something to go from one end to the other (Ballard
2000). A production planner needs information not only regarding
assignment or work task loads but also regarding resource capacity as
shown in Fig. 2.
Work task loads and resource capacity may be assessed both
quantitatively and qualitatively. When focusing on quantity, load is the
amount of work within a specific time that is assigned through planning,
and capacity is the amount of work a crew (or production unit) can
perform during the planning span given specific tools and work methods
under site conditions. Quantitative assessment can be represented in
work quantity per resource volume, e.g., painting 30 square
feet/man-hour) (Holm et al. 2004). Estimating references such as R.S.
Means and customized estimating database use the quantitative approach
in accessing work task loads and resource capacity. However, current
estimating unit rates, such as the labor hours required to place a cubic
yard of concrete, are at best averages based on historical data. Such
data are themselves laden with the tremendous amounts of waste imbedded
in conventional practice (Ballard 2000). Real and estimated values can
differ largely depending on many variables such as site conditions and
actual work force configuration. In other words, current quantitative
assessment contains a high level of uncertainty.
On the other hand, the qualitative approach deals with the quality
of resources and how work tasks are performed. When focusing on the
quality approach, load can be any required work tasks in the actual site
conditions. For example, some work tasks would require that workers be
educated first about a special safety requirement. Capacity in this
approach refers to the qualitative capability of a crew such as
experiences and safety records.
[FIGURE 2 OMITTED]
Whatever the accuracy of load and capacity estimates is, the
planner must still make some adjustments by taking into account
qualitative factors such as actual site conditions. After adjusting the
load and capacity, either load can be changed to match capacity,
capacity can be changed to match load, or, more commonly, a combination
of the two (Ballard 2000). However, matching load with capacity using
the qualitative approach is still difficult to achieve. In many cases,
information on workforce capacity remains unavailable in production
planning for several reasons. For example, the level of workmanship is
difficult to track and manage even in cases when labor turnover rate is
high. However, information on the quality work tasks and capacity is
important in matching work task loads with resource capacity during
production planning. This research uses a database coupled with RFID
technology in order to track and maintain load and capacity information
in both quantitative and qualitative approaches. This paper shows how to
assess work tasks and capacity in both approaches, though which we
pursue more accurate matching of load with capacity.
3. Mobile communication technology
This research uses mobile communication technology to track data.
The applications of RFID, which is one of the key devices in MCT, are
the essential components in the processes undertaken by the construction
industry. Many research projects have shown the benefits of RFID
applications including in concrete operations, personnel management,
productivity analysis, construction tool tracking and pipe spool
tracking (Jaselskis et al. 1995; Jaselskis, El-Misalami 2003; Song et
al. 2006a). RFID is one of the important automatic identification
techniques currently being used in many industries. The RFID tag is a
small wireless computer chip that could be embedded into almost any
product. It uses an on-board microprocessor and an antenna to wirelessly
transmit and receive certain information uniquely related to the item.
The RFID tag uses a small and inexpensive passive tag with an unlimited
life cycle.
Recently, several attempts have been made in applying RFID
technology to the construction industry. Ergen et al. (2007) suggested
using RFID in facility management. Tests have been conducted in order to
determine the technological feasibility of RFID within a facility on a
daily basis with active RFID (Sarma, Engels 2003). Song et al. (2006b)
evaluated the use of RFID technology in tracking pipe spools through a
long supply chain. Through his pilot studies, Schneider (2003) asserted
that RFID is an effective method in reducing project activity time and
cutting project costs.
PDAs, on the other hand, comprise one of the state-of-the-art
technologies in MCT that have appeared on site application in recent
years. Kimoto et al. (2005) describes aim, concept based on End User
Computing, and the essential element of the mobile system as well as the
structure of the system and outline of subsystems. Chen et al. (2002)
suggested that the PDA can collect information in real time and makes
available this information for analysis the next day. Also, Burgy and
Garrett (2002) insists that mobile computing can eliminate and/or
decrease the gap between outdoor construction site and the indoor
office. Construction managers may effectively use digital data input
using the mobile computing device on the construction site. Kim et al.
(2008b) presented a computerized Quality Inspection and Defect
Management System (QIDMS) that can collect defect data at a site in real
time using a Personal Digital Assistant (PDA) and wireless internet.
Wang (2008) and Kim et al. (2008b) showed the advantage of adopting
online portals and mobile devices in the quality inspection process. Kim
et al. (2011) adopted RFID while the ZigBee protocol was tested in an
indoor environment for monitoring construction material. RFID was used
in another research (Moon, Yang 2010) to improve communications during
concrete pouring operations.
Most of the recent articles have emphasized how IT can effectively
be activated in construction sites to help improve the quality and
efficacy of construction work. However, no research work has been
conducted on the use of IT on production planning, especially with
regard to gathering exact information about workforce capacity.
The above papers show that the use of RFID and PDA can benefit the
construction industry with applications in various management areas such
as materials management, tracking of tools and equipment, automated
equipment control, jobsite security, maintenance and service, document
control, failure prevention, quality control, field operations and
construction safety.
4. Assignment loads
To define assigned loads, contractors observe the following
processes: quantity takeoff, calculating how crew numbers of each
production unit would execute each work task and assessment.
4.1. Quantity takeoff
Quantity takeoff is one of the most important processes during
pre-construction. If the amount and costs of construction materials are
lower or higher than optimal, a contractor may fail. Also, if
contractors, upon calculating quantity takeoff, do not know their own
productivity such as workforce and equipment productivity, they may
encounter much difficulty. Therefore, big or small contractors maintain
not only their own quantity takeoff guidelines and database but also
productivity database. The following table is an actual productivity
data used in an actual Korean construction company (Quantity takeoff
guideline and DB are not included in this paper).
4.2. Quantitative production unit capacity
After obtaining quantity takeoff, contractors usually calculate how
many people and equipment will be involved in the project. A sample
calculation for a condominium project is presented below:
--Form work: 648 [m.sup.2];
--Rebar work: 8 ton;
--Concrete: 180 [m.sup.3].
From the workforce productivity database, a contractor can easily
find the exact figures in Table 1. Similarly, a contractor can find
information related to duration per floor from their database (see C.
Duration per floor). Using duration per floor, contractors can acquire
the figures (see D. Amount per duration). Contractors could then
determine exactly how many workers are needed in building one
condominium floor (see E. Calculation workforce per day). Below, Table 2
shows how many workers are needed in each work: form workers--6; rebar
workers--4; and concrete workers--3. Contractors can then select workers
based on the exact information.
4.3. Work task assessment
After contractors devise a master schedule, a monthly schedule, and
a weekly schedule, contractors or subcontractors in the field can
imagine which work task needs to be constructed for a given week or day.
Subsequently, they could correctly begin to assess risks. As in Fig. 3,
they input figures according to how difficult or dangerous the work
tasks are. An assessment could determine levels of difficulty according
to impact and occurrences: Level 1 is no risk; Level 2--low risk; Levels
3-4--middle level; Level 5--high risk; and Level 6--extremely high risk.
The Figure shows an example of "Scaffolding and Wire Mesh"
related to work task assessment. If a work task was defined by the
standards of the Korean Occupational Safety and Health Agency (KOSHA),
that work task must follow guidelines that were set by KOSHA. S means
safety, E means Environment, and Q means quality. Each work task has
three different attributes, and contractors or subcontractors should
assess them according to the risk level. If work task is classified
Level 2 in terms of safety, environment and quality, contractors or
subcontractors would issue a warning before construction work is done.
[FIGURE 3 OMITTED]
4.4. Problems in selecting production units
From the above tables and figure, contractors become aware of how
many people will be involved in a work task and how difficult or
dangerous construction will be. Because a construction project needs
many people, contractors usually tend to choose not an individual person
but an entire production unit. Subsequently, they face the real problem,
which will be the right production unit for this project?
Though contractors can calculate the exact figure, if they do not
have the right information about a production unit's capacity, they
cannot be certain of their success. Therefore, they should first gather
quantitative and qualitative information.
5. Workforce Information Database System
Though a production unit's capacity is important in production
planning, construction managers and site managers are not aware which
attributes of the production unit capacity are important in a workforce
and how workforce capacity information on site can be gathered. This
research, therefore, investigated which capacity is important based on a
survey, and suggested a workforce information database system in order
to collect workforce capacity information using RFID and PDA.
5.1. Major factors in determining a production unit's
qualitative capacity
The authors surveyed 136 project engineers and managers to
investigate what workforce information can be useful for
production/safety planning and control. Table 3 shows the survey
results. The system tracks and manages the following information:
--General personal information (age, nationality, passport number,
workmanship);
--Safety records;
--Work experience and level of workmanship.
Therefore, in production planning design, contractors have to know
a production unit's capacity, which depends on skill, experience
and safety history. These three major factors are the basic elements
that should be included in the workforce information database system for
contractors. However, collecting, tracking and managing workforce
information in the field is not easy, so this research adopts MCT,
specifically RFID and PDA technologies.
5.2. System architecture in Workforce Information Database System
A web-based version of the Workforce Information Database System
that is mainly used by foremen, field engineers, superintendents, and
site managers, has been recently developed. A simple database scheme,
designed for workforce information databases, has been used. Fig. 4
illustrates the Entity Relation (ER) diagram for the databases, which
shows the type of data and relationships between data. Tables regarding
general information include data on personal information, eligibility of
work and visa status. Tables regarding safety records include data on
health, safety violation and training records. Tables regarding work
history and workmanship include employment history, previous projects
and level of workmanship.
[FIGURE 4 OMITTED]
5.3. Description of Workforce Information Database System
Information on a new worker who just arrived on site needs to be
registered in the workforce information database system. Once
registered, the worker receives a temporary ID embedded with a passive
RFID tag. As the tag is scanned, the information is simultaneously sent
to the workforce information database system. Front line mangers
instantly get exact information on how many people come on site and when
they arrive.
There are three methods of inputting workforce information into the
database system. First is with the use of the RFID tag, which records
when personnel arrive and leave. The second involves the use of the
Internet on the site or at the headquarters office, which is the most
common way used for information input. The last is by using PDA, a kind
of web accessing device, that allows field engineers to instantly input
all information about their workforce. This paper mainly focuses on the
third method.
The sample windows below show what information can be retrieved
from the workforce information database system. Figs 5, 6 and 7 give
actual screen dumps from the workforce information database system. Fig.
5 shows data input screens regarding general personal information. The
Entry Form under the section "General" allows the user to
enter information about their job, contact information, evidence of work
eligibility and work location. In work location, a worker registers his
or her company and work team (production unit). All this information
will be applied to production planning.
In the same manner, information about safety records is entered
using the data entry form as shown in Fig. 6. Three types of safety
data, health status, safety violation and safety training status, are
updated and managed in order to prevent accidents.
[FIGURE 5 OMITTED]
[FIGURE 6 OMITTED]
The database system also allows the user to enter work experience
and the level of workmanship for each work as shown in Fig. 7. Level of
workmanship is usually evaluated by field engineers or site managers.
This grade can be referred to by the next project's field
engineers, updated or modified. In many cases, however, such information
is not properly managed and maintained. The workforce information
database system builds a range of comprehensive information regarding
each worker's capacity including the level of workmanship and
safety records.
5.4. RFID System
RFID is the next wave in the evolution of computing. Employee ID
cards with passive RFID tags are scanned by a reader when employees pass
through the gate. The system operates at 13.56 MHz, taking into account
the readable range required on sites (Fig. 8).
[FIGURE 7 OMITTED]
[FIGURE 8 OMITTED]
5.5. Workforce Information Database System using PDA
PDA is one of the most powerful devices in the construction site.
Usually, a construction site area is wide or has so many layers such
that the site office is far from field engineers.
The first window of the PDA has two major functions, Safety
Violation (Fig. 9) and Personal records (Fig. 10). Using a PDA, field
engineers can retrieve and input information on their workers. All the
information in a PDA and in the workforce information database system is
synchronized.
When field engineers click the Safety Violations button, they are
directed to the Worker List window. Then, they select a team within the
subcontractor and search the name of a worker, specifically selecting
the one who violated a safety policy. The safety violation history of
the selected worker shall then be displayed. Also, if the worker later
commits another violation, a field engineer may choose a violating item
and click on the Save button.
This shows how engineers and managers can input violation records
simultaneously on site as well as how they can see workforce records
about safety.
The next function is about personal records. The Personal Records
Menu has 4 sub taps that include Basic, Safety, History and Skill. Each
tab is synchronized with the workforce information database system
windows, Figs 5, 6 and 7, respectively. Using the Basic tab, field
engineers can refer to individual information on a worker's
company. If they want to check someone's records, they will click
on the button on the right side of Company, select a team, click on
Search button for a worker's name and then select an option. If
they click the Photo button, they can even see a worker's photo. In
the second Safety tab, detailed information on safety violation history
as well as safety training history of the person is referred to. In the
third History tab, engineers and managers can view the past career of a
worker in the current site he or she is in as well as previous
construction sites. In the Skill tab, they can see the skill type,
grade, work site and evaluator for a certain worker.
[FIGURE 9 OMITTED]
[FIGURE 10 OMITTED]
[FIGURE 11 OMITTED]
[FIGURE 12 OMITTED]
PDA and RFID technologies can simplify the collection, tracking and
managing of workforce information in the field. Data can be retrieved by
the users who need the information in determining a production
unit's capacity.
6. System implementation
Production planning needs to determine assigned loads and a
production unit's capacity, and the proposed workforce information
database system can provide both. The system also gives balanced views
to construction managers and site managers because they have both sides
of the information: quantitative (assignment loads) and qualitative
(production unit's capacity). The next example demonstrates how to
create a production plan.
Contractors or subcontractors set up each work task from a weekly
schedule. They can determine which work tasks are done on a given day.
Fig. 11 shows an example work task schedule. There are 3 work tasks on
September 28: CENTERING and LEVELING, GROUTING, and ALIGNMENT.
Managers then assess the attributes of the work tasks such as the
level of work task, difficulty and so on. After assessing, they confirm
the figure that is placed on each work task from 1 to 6 as shown in Fig.
3.
Based on work task assessment, contractors can retrieve a possible
production unit from the workforce information database system. Each
production unit has detailed information when it registered in the
workforce management database system. As shown in Fig. 12, for example,
the user can view a suitable production unit based on a unit's
level of workmanship, safety records and experience in GROUTING, for
instance.
In this example, contractors cannot help but choose the production
unit of Pablo L. Torres, because Pablo's team has S grade, which
indicates no accident record and four project experiences.
7. Discussion
7.1. Survey methodology
It was difficult to validate the effectiveness of the workforce
database management system prototype on a full scale. Instead, the
authors implemented a survey to assess the system's effectiveness.
The authors developed questionnaires to identify the benefits of the
suggested system. The questionnaires were distributed to a group of five
project mangers and were revised according to the comments from a pilot
survey. In constructing the questionnaire, a Likert scaling system was
used. The scale is a seven-point rating scale in which the attitude of
the respondent is measured on a continuum from highly favorable to
highly unfavorable, or vice versa, with an equal number of positive and
negative response possibilities and one middle or neutral. The questions
related to the system are as follows:
1) Sample question: Does this system help when you perform
production planning?
2) Sample question: Does this system help when you perform safety
planning?
3) Sample question: Does this system help when you count the number
of crew on site?
A total of 91 foremen, superintendents, field engineers, and site
managers who have used the proposed system were asked to answer the
questionnaire and provide comments. Table 4 shows the survey results
using the seven-point Likert scale questions, in which a score of
"1" corresponds to "Least Helpful" and a score of
"7" means "Most Helpful".
7.2. Benefits from the suggested system
Benefits from the suggested system have been identified in Table 4
and they are grouped into two categories throughout the survey:
1) Accurate workforce capacity for production and safety planning.
In the suggested system, safety, skill and experience information are
used for production planning. There is great potential (average 6.0,
5.6) when workforce information is used by a contractor in production
planning and safety planning. The case study result also showed that the
weekly percent plan completion (Ballard 2000) improved by around 6-10%
based on a 4-week moving average;
2) Faster counting of crew on site. An additional benefit in using
RFID technology is the reduced time and effort in counting the number of
workers. In the traditional approach, each field engineers spends 5 to
20 minutes during the daily head-count. Through the RFID, no other
resources are required to count the number of crew members on site. The
information can be easily grouped into work divisions or work areas. The
time required for processing time cards for employees has been
drastically reduced.
8. Conclusions
A production plan, which essentially matches capacity with loads,
is required in managing construction projects. The capacity of
production units (or crews) is dependent on qualitative attributes as
well as quantitative capacity. Developing a production plan involves
several steps. With quantity takeoff, contractors can calculate
assignment loads and match assigned loads appropriately to a production
unit. However, gathering and transmitting a production unit's
qualitative capacity information is not easy on site.
We addressed this issue by investigating which workforce
information can be useful in production/safety planning and control
through a survey. The survey showed that four types of information
(general personal information, safety records, work experience and level
of workmanship) are needed. This paper proposed a prototype database
that provides the information on production units' capacity,
especially qualitative attributes, to a production planner. The research
also demonstrated how the prototype system can be used. The
system's effectiveness and efficiency were also tested through a
survey.
The survey results showed that the information provided by the
prototype system: (1) has high potential (average 6.0, 5.6) for use in
workforce capacity in production and safety planning respectively; and
(2) it reduces time consumed in counting the number of crew on site.
The proposed system contributes to the knowledge and practice of
production planning since it elaborates on how qualitative workforce
information is defined and managed in a workforce database system.
Contractors can easily obtain accurate information about each production
unit's capacity, and select the appropriate production unit for
each work task.
We expect that the quality of production planning process will be
improved by more precise matching of capacity with loads through the
suggested process and aided by the workforce database. In the long run,
the suggested process and system can contribute to improving
productivity as well as planning reliability, which is outside the scope
of this research.
doi: 10.3846/13923730.2012.725675
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Sang-Chul Kim (1), Yong-Woo Kim (2)
(1) Hanbat National University--Architectural Engineering, Daejon,
Republic of Korea
(2) University of Washington--Construction Management, Box 351610
120 Arch Hall, Seattle, Washington 98195, United States
E-mails: lharvard9@naver.com; 2yongkim@u.washington.edu
(corresponding author)
Received 05 Apr. 2011; accepted 02 Nov. 2011
Sang-Chul KIM. Assistant Professor at the Department of
Architectural Engineering, Hanbat National University, Daejeon, South
Korea. He is a member of Korea Institute of Construction Engineering and
Management (KICEM). His research interests are Earned Value and its
application to construction field, construction management system to fit
to construction employees.
Yong-Woo KIM. Associate Professor, P.D. Koon Endowed Professor of
Construction Management, College of Built Environments, University of
Washington, Seattle, WA. He is a member of American Society of Civil
Engineers (ASCE). His research interests include lean construction and
supply chain management.
Table 1. Manpower productivity in condominium project
Workforce Productivity
Classify Attribute Activity Unit Average
(1day)
Scaffolding Dismantle [m.sup.2] 57.6
scaffolding
(Double)
Dismantle [m.sup.2] 117.3
scaffolding
(Single)
Form Parking lot R.C structure [m.sup.2] 18.3
Condo R.C structure [m.sup.2] 27.0
Rebar Parking lot R.C structure ton 1.4
Condo R.C structure ton 1.0
Concrete Parking lot R.C structure [m.sup.3] 66.4
Condo R.C structure [m.sup.3] 50.8
Brick Brick EA 1,585.7
Plastering Parking lot Plastering [m.sup.2] 42.1
Condo Plastering [m.sup.2] 32.9
Water Parking lot Water proofing [m.sup.2] 48.3
proofing Condo Water proofing [m.sup.2] 36.7
Tile Tile in floor [m.sup.2] 19.4
Tile in wall [m.sup.2] 18.0
Stone Stone in [m.sup.2] 3.6
washroom's wall
Stone in [m.sup.2] 3.9
washroom's floor
Stone in entrance [m.sup.2] 6.0
Exterior stone [m.sup.2] 6.3
Glass Interior, [m.sup.2] 111.3
exterior glass
Furniture Closet in bedroom Set 23.0
Closet in entrance Set 21.0
Table 2. Calculating production unit
Case Study
A. Condition Condominium
1. Form 648 [m.sup.2]
2. Rebar 8 ton
3. Concrete 180 [m.sup.3]
B. From DB
Form Parking lot R.C structure [m.sup.2] 18.3
Condo R.C structure [m.sup.2] 27.0
Rebar Parking lot R.C structure ton 1.4
Condo R.C structure ton 1.0
Concrete Parking lot R.C structure [m.sup.3] 66.4
1 Condo R.C structure [m.sup.3] 50.8
C. Duration
per floor
1. Form workman 4 day/cycle
2. Rebar workman 2 day/cycle
3. Concrete workman 1 day/cycle
D. Amount per
duration
1. Form workman 162 [m.sup.2]/day (648/4)
2. Rebar workman 4 ton/day (8/2)
3. Concrete workman 180 [m.sup.3]/day (180/1)
E. Calculating
workforce per day
1. Form workman 162/27 6 people
2. Rebar workman 4/1 4 people
3. Concrete workman 180/50.8 3 people
Table 3. Survey result on useful workforce information
Information No. of people who Percentage
chose the
information useful
Job Classification 124 93.9%
Accident record 121 91.7%
Communication Skill 54 40.9%
Level of Workmanship 116 87.9%
Training record 71 53.8%
Violation record 89 67.4%
Work experience 85 64.4%
* Total number of respondents, 132; non-respondents, 4.
Table 4. Survey result on benefits with the proposed system
Information No. Production Safety
planning planning
Commercial Building Foremen 7 6.1 6.0
project Superintendents 6 5.8 5.5
(23 sites) Field Engineers 8 6.3 6.1
Site Managers 4 6.4 6.2
Residential Foremen 9 6.0 5.5
project Superintendents 8 5.9 5.2
(31 sites) Field Engineers 15 6.4 5.8
Site Managers 9 6.1 5.5
Civil Foremen 4 5.5 5.0
project Superintendents 5 5.3 5.2
(14 sites) Field Engineers 3 6.0 5.8
Site Managers 3 5.9 5.6
Industrial Foremen 2 6.0 6.0
project Superintendents 4 5.8 5.2
(8 sites) Field Engineers 3 5.9 5.2
Site Managers 1 6.0 5.0
Total/Average 91 6.0 5.6
Information Time of Easy to Average
Counting operate
Commercial Building Foremen 6.3 2.5 5.2
project Superintendents 6.4 2.8 5.1
(23 sites) Field Engineers 6.6 3.4 5.5
Site Managers 6.1 3.0 5.4
Residential Foremen 6.6 2.4 5.1
project Superintendents 6.7 2.1 5.0
(31 sites) Field Engineers 6.4 3.5 5.5
Site Managers 6.2 3.1 5.2
Civil Foremen 6.3 2.2 4.7
project Superintendents 6.4 2.0 4.7
(14 sites) Field Engineers 6.5 2.8 5.3
Site Managers 6.6 2.6 5.2
Industrial Foremen 6.0 3.0 5.2
project Superintendents 6.4 3.3 5.2
(8 sites) Field Engineers 6.0 3.5 5.1
Site Managers 6.0 4.0 5.2
Total/Average 6.3 2.9 -
* Total number of respondents, 91, 1 = Least Helpful, 7 = Most
Helpful
