LIST OF APPENDICES

4.4. Multiple Calendars Analysis in Microsoft Project and P3

The template charts for all relationship types and lag conditions are analyzed and shown. The data of these charts are directly inputted in Project and 3P. The analysis is done for both forward and backward pass. Each following result’s figure is shown in template charts, Project and P3 forms. This is done for easy comparison of differences and error generation by the software.

4.4.1. Special Case Analysis in Project and P3

When dealing with multiple calendars in Project and 3P, it is been seen that both software generates different output in certain special cases. These special cases occurs when if the lag time is negative for all relationship types and if the earliest possible time of the successor after applying the lag time is the beginning of the next day of a nonworking day on the predecessor’s calendar. Presumably, no additional consideration is given to this special case without taking into account possible earlier times hidden by the nonworking days of the predecessor’s calendar. Both software packages are known to keep minimum lag time between two activities, but it does not take account of possible earlier finishing times to finish the project earlier by utilizing those hidden working days of the other calendar.

Figure 4.4 shows two activities, activity A and B, scheduled in two calendars, calendar 1 and 2, with four and five working days, respectively. The relationship type is Finish-Start with negative one lag. With FS: -1 day from the predecessor, the successor can start whenever the remaining duration of the predecessor is at most 1 day if it does not have links to other successors. Since the lag belongs to the predecessor’s calendar (refer 2.5.1, Rule 1), Activity A can finish at day 8 and become the EST (Early Start Time) for Activity B if it is scheduled in the same calendar and day 7 is a working day. However, since this schedule does not fulfill Figure 4.4 shows two activities, activity A and B, scheduled in two calendars, calendar 1 and 2, with four and five working days, respectively. The relationship type is Finish-Start with negative one lag. With FS: -1 day from the predecessor, the successor can start whenever the remaining duration of the predecessor is at most 1 day if it does not have links to other successors. Since the lag belongs to the predecessor’s calendar (refer 2.5.1, Rule 1), Activity A can finish at day 8 and become the EST (Early Start Time) for Activity B if it is scheduled in the same calendar and day 7 is a working day. However, since this schedule does not fulfill

Figure 4.5 shows a similar example for the Finish-Finish (FF) with negative one lag time. This figure however has three possible EST for Activity B; day 8, day 5 and day 4. The earliest EST for Activity B would be day 4. The output generation of Project and P3 is day 5, which still can be accepted as an EST for Activity B. But since day 4 is still accounted as the earliest EST for Activity B, preferably, day 4 should be chosen. Figure 4.6 and 4.7 are examples for Start-Finish and Start-Start with negative lags relationship, respectively.

Another type of relationship that has a mistaken conception output in Project and Primavera is the Start-Start relation with zero lag. Unlike other relationship types of zero lags, the earliest possible finish time of the successor in SF: 0 is the previous day of the predecessor’s time as in negative lags. Thus, the same treatment for the negative lags should be applied to SF: 0. As shown in Figure 4.8, Activity A starts on day 8, after Activity M that has the Finish-Start with zero relationship. The successor, Activity B with Start-Finish (SF) relationship can finish at the end of day

7. Since end of day 7 is the same as the beginning of day 8, which is the next day of a non-working day on the predecessor’s calendar, the same method applied to the negative lag needs to be applied as shown on the bar chart. So, as Activity A will start at day 5, the successor, Activity B, must not finish earlier than end of day 5.

Project and 3P produces different outputs separately in dealing with SF: 0 cases. The earliest of all Early Finish Time (EFT) of Activity B in Project is the beginning of Day 8, which is also happen to be the end of Day 7, a non-working day. This violates the concept of multiple calendars in network analysis. In 3P, earliest

EFT for Activity A is on Day 3, which defies the relationship of SF: 0 conditions. In this case, 3P produces a -2 lag, which violates the relationship condition of zero lag.

Project and P3 produce output of EST of day 9

The earliest EST:

Output of Project and P3:

Figure 4.4: Finish-Start (FS) with lag negative (Special Case).

The earliest EST:

Output of Project and P3:

Figure 4.5: Finish-Finish (FF) with negative lags (Special Case).

1 2 3 4 5 6 7 8 9 10 11 12 13 14 Calendar 1 Calendar 2

The earliest EST:

Output of Project and P3:

Figure 4.6: Start-Finish (SF) with negative lag (Special Case).

The earliest EST:

Output of Project and P3:

Figure 4.7: Start-Start (SS) with negative lags (Special Case).

Calendar 1 Calendar 2

The earliest EST:

Output of Project and P3:

Figure 4.8: Start-Finish (SF) with zero lag (Special Case).

4.4.2. Additional Errors in Project

Project generates several incorrect outputs in conditions when dealing with multiple calendars situations apart from the special cases as mentioned in section

4.3.2. Below are a few cases analyzed in Project.

In Figure 4.9, the template chart shows a FF: 0 relationships between two activities with two calendars. From the bar chart, it is noted that predecessor (Activity A) finishes on day 5, next day to a non-working day. The successor (Activity B) could not finish on day 4 to fulfill the relationship given. This is because the end of day 4 is identical to the beginning of day 5, which happen to be a non- working day. Therefore, the earliest EFT for Activity B would be on day eight and no earlier times. (Refer 2.5.1, Rule 6).

The output of Project in Figure 4.9 is end of day 5, which happen to be a non- working day. Figure 4.10 for FF: -1 lag time supports the matter. In this case, it clearly shows the violation of Rule 7. Project’s output of Activity B’s finish time is day 3, the next day to a non-working day.

Another type of violation of multiple calendars detected in Project is shown in Figure 4.11. Activity A begins after a FS: 0 relationships with Activity M and the latter are followed with Activity B in a SS: +1 relationship. Activity A, after the calculation of the lag time starts on the end of day 5, thus its successors with SS: +1 can start at the beginning of Day 6 or later. Since Activity B belongs to Calendar 2, it cannot start on Day 6 (a non-working day). Activity B can start at the beginning of Day 8, which is the next available working day on Calendar 2.

The output of earliest EST for Activity B in Project is day 9. In this matter, Project assumes the lag time belongs to the successor’s calendar, which violates the Rule 1 that states the lag time calculation belongs to the predecessor’s calendar (refer

2.5.1, Rule 1). Examples that are similar to this condition are shown in Figure 4.12 for FS: +1. However, in the case of relationship type FS:-1, a dialog box appears to alert the user about the conflict in scheduling. Further discussion about the warning dialog box will be shown in section 4.4.4. Figure 4.13 shows the latter.

The earliest EST:

Output of Project and P3:

Project generates an incorrect output. In addition, no conflict linking warning dialog box were displayed.

Figure 4.9: Finish-Finish (FF) with zero lags (Project)

The earliest EST:

Output of Project and P3:

Figure 4.10: Finish-Finish (FF) with negative lag (Project)

Calendar 1

Calendar 2

The earliest EST:

Output of Project and P3:

Figure 4.11: Start-Start (SS) with positive lags (Project)

1 2 3 4 5 6 7 8 9 10 11 12 13 14

Calendar 1

Calendar 2

The earliest EST:

Output of Project and P3:

Figure 4.12: Start-Start (SS) with negative lags (Project)

The earliest EST:

Output of Project and P3:

Figure 4.13: Finish-Start (FS) with positive lags (Project)

Calendar 1 Calendar 2

A warning dialog box appears to show there is a conflict in linking Activity A and B with the

relationship of FS:-1.

Figure 4.14: Finish-Start (FS) with negative lags (Project)

4.5. Flexibilities and Deficiencies of Project and P3

Apart from miscalculation of both software packages in handling multiple calendars, other aspects are also analyzed in this section. The scope of analysis in this paper is limited to scheduling aspects. Resource analyses are not included in this paper. The aspects that are analyzed in this section are as below. These aspects are use as a comparison between the two software packages

• Calendars • Activity input and WBS • Link conflicts.

4.5.1. Calendars in Project.

Project has an efficient calendar system that includes the working hours that cannot be found in P3. These working times can be set in the base calendar. It then calculates the working hours for per day, week, and month (Figure 4.15). The times can be further defined for break times. In real time construction project, machineries and plants are paid in hourly basis. This function of time set-up serves as an advantage for payment of these resources.

Projects also have the visualization of non-working days in the Gantt chart view. These ease the viewer to identify the non-working days per week. Project can manage to establish a single shaded or colored view for a single calendar (Figure 4.16). This becomes a drawback if more than one calendar is used in a single project. The non-working times from other calendars remains invisible on the Gantt chart view.

Project has three types of calendars, the Project calendar, the Task calendar, and the Resource calendar. This is useful when a project deals with variable task and resource timing. Task calendars can be modified to working and non-working days specifically for a single task that needed to be modified. The same applies to the Resource calendar for resource availability. The downside in this aspect is, when a task is assigned to both of these calendars at different working time. Project uses only common schedule the task. Figure 4.17 shows both Resource and Task calendars with 9:00 a.m. to 5:00 p.m. and 11:00 a.m. to 8:00 p.m. working times, respectively. Project schedule the task to 9:00 a.m. to 8:00 p.m., the only hours the calendars have in common. Project also allows new calendars assigned as Project calendars.

Unlike P3, desirable working hours per day can be

inputted in Project. By default, Project uses common

office-working hour times with 1 hour break. Furthermore, each day can be set-up with different

working hours.

Project calculates hours per day, week, and month base on inputted working hours per day.

Figure 4.15: Working hours in Microsoft Project

Project shows only 1 calendar’s non-working times in its Gantt chart.

Figure 4.16: Non-working hours in Microsoft Project

Figure 4.17a shows

a resource is assigned to 9:00

a.m. to 5:00 p.m.

Working hours can

be organized accordingly to

resource availability.

Figure 4.17a: Resource calendar

Figure 4.17b shows a task is assigned to 11:00 a.m. to 8:00 p.m.

When a task and resource with separate working hour assigned

to a single task, Project will schedule the task in common

working hours. In this case, the common working hours would

be 9:00 a.m. to 8:00 p.m.

Figure 4.17b: Task calendar

4.5.2. Calendars in P3

P3 offers 2340 resource calendars and 31 task calendars. Unlike Project, P3 can define yearly repeating holidays when assigned. This avoids repeating assigning of holidays in every year’s calendar. Figure 4.18 shows these matters.

The major drawback of P3 is that it does not allow time scheduling. Contrasting Project, working hours cannot be defined in P3. Compared to Project, the Gantt chart visualization of P3 is shows the necking for non-working days on the bar. Figure 4.19 displays the matter. This allows the user to have clearer understanding of the Gantt chart.

3P has the advantage of setting up holidays and

repeating the date yearly.

Figure 4.18: Holidays repeating option

P3 shows necking for non-working days

Figure 4.19: Necking for non-working days.

4.5.3. Activity Input and WBS in Project

Project has organized activity input with the support of follow-on easy user- friendly wizard. The activity ID in Project starts with 1 and the next ID follows with the continuing number. A new column must be inserted for users-define activities Outline Code option. Project offers up to 10 sets of custom outline codes in a single project. Dissimilar to P3, Project offers the total length up to 255 characters per outline code in both alphabets and numbers or both (Figure 4.20).

Outline codes are also used in Work Breakdown Structure (WBS). WBS defines as hierarchal structure that is used to organize task, resources, and cost. Project allows 65000 levels indented from the top level. This is a plus point for mega project managements which have a large number of activities that needs to organize in a WBS. Project conducts an automatic WBS code input for every activity entered and every activities and sub-activities has it own WBS codes. Columns can be added to display show the WBS level. This serves as a user time saving advantage. In addition, the Gantt chart displays the hierarchy of the top level and the level below with different colors. This creates a trouble-free view at the Gantt chart unalike from P3, where colors separations are not demonstrated. WBS levels can also be displayed for better understanding of the level structure (Figure 4.21)

Project offers the total length up to 255 characters per outline code

in both alphabets and numbers or both.

Figure 4.20: WBS Code Definition.

Columns can be added to

Unlike P3, Gantt chart in display the WBS and

Project have the capability to

Outline Level

show the hierarchy of the WBS

Figure 4.21: WBS Hierarchy Display.

4.5.3. Activity Input and WBS in P3

In contrast to Project, P3 allows user defined activity ID. This is an advantage to the user to define preferable ID in either alphabetical letters or numbers or both. P3 automatically numbers activity ID with user defined number increment option that can be found Activity Inserting Option. A non-defined increment set-up uses the multiples of 10 for each activity. This automatic activity ID input can be turned off to start with a new type of increment pattern (Figure 4.22).

Activity ID input in P3 serves an advantage when working on the WBS. Activity ID simplifies the identity of its sub-activities (Figure 4.23a). P3 has the limitation of 20 levels in WBS and each stage is limited to maximum width of 10. This is a minus point for P3 as Project has 65000 levels in WBS. The lower level activities follow its upper level, adjustment in placing the sub-activities in other activities groups are not allowed. Another drawback in P3 is that its first level’s activity input is an independent phase that does not reflect on an activity. It simply means no activity descriptions; such as activity ID, duration and etc. can be inputted. It basically reflects as a topic of an activity group. In the other hand, Project defines its first level as an ordinary activity with all activity descriptions. Furthermore, P3 does not allow the hierarchy of the WBS in the Gantt chart view which creates a complicated view of the chart (Figure 4.23b).

P3 automatically numbers activity ID with user defined number increment option

Figure 4.22: Activity Code Increment Option.

ID input in P3 is easy when working on the WBS. Adjustments in activities are not allowed in P3.

Figure 4.23a: WBS hierarchy in P3.

First level of WBS in P3 serves as the title

Dissimilar to Project, P3 does not of a activity group rather than an activity.

show the WBS hierarchy in different colors.

Figure 4.23b: WBS hierarchy in P3 and Gantt chart.

4.5.4. Link Conflicts in Project

Project displays a warning dialog box when a conflict link has been founded during relationship input (Figure 4.24). The purpose of this is to alert the user about the fault linking of activities. User is given a choice of avoiding the scheduling conflict or to continue with the fault scheduling. But, in the choice of the latter, the further data input is restricted. This approach in Project is useful to avoid false scheduling.

In the case of scheduling with multiple calendars (refer section 4.3.2), it is known that relationship types of SF and FF with zero and negative lag times and FS and SS with positive and negative lag times produces incorrect answer. However, it has been noticed that none of the incorrect outputs from the relationship types mentioned in the latter section displays the warning box. It is therefore can be concluded that full reliance of this warning dialog box must be avoided.

Figure 4.24: Scheduling Conflict Warning Box

4.5.5. Link Conflicts in P3

P3 does not display warning dialog boxes although conflict appears during scheduling. P3 does the correction without informing the user. This can be a minus point for the user as they could not track the area that needed to correct. Data entry also is not affected after a conflict link.

In this modern age, construction management software has become vital due to ever increasing sophisticated projects. Project and 3P are the leading construction management software in current market. Both software packages are recognized in handling complicated construction management projects and the outputs are known to be reliable.

Conventional CPM methods are used in scheduling a single calendar. However, special consideration must be made in scheduling with multiple calendars. Additional set of rules has been researched (Kyunghwan and Garza, 2005) to prove that the conventional CPM methods are invalid in multiple calendars situations.

The primary objective of this research is to identify the miscalculation occurring in Project and 3P in handling multiple calendars. The secondary objective of the research is a comparison between Project and P3 in aspects of calendars, activity input, Work Breakdown Structure, and activity linking.

5.2. Special Case Conditions in Project and P3

For the first objective, studies have been conducted to determine the conditions in which miscalculation occurs in both software packages. It has been identified that two conditions of errors occurring. In this section, conclusions are made for ‘special case’ conditions in multiple calendars. ‘Special case’ here refers to the situations where the beginning of the next day, when the activity has been counted for its lag time, is a nonworking day on the predecessor’s calendar.

In overall, it can be concluded Project and Primavera could not generate the earliest EST or EFT for the successor under these circumstances:

• Negative lag times in relationship types of Finish-Start, Finish-Finish, Start- Finish and Start-Start • Start-Finish conditions of zero lag time.

5.3. Additional Errors in Project

The ‘additional errors’ here reflect on the additional conditions that are not the ‘special cases’, but errors are still experienced in Project.

Project generates outputs in which the finishing time of the successor in relationship types of Finish-Finish with zero and negative lag times is the next day to

a non-working day, in which violates Rule 6. Another violation in Project is in relationship types of Start-Start and Finish-Start with positive and negative lag times, in which Project assumes the lag times, belongs to the successor’s calendar. This defies Rule 1 that states the lag times belong to the predecessor’s calendar. However, a non-working day, in which violates Rule 6. Another violation in Project is in relationship types of Start-Start and Finish-Start with positive and negative lag times, in which Project assumes the lag times, belongs to the successor’s calendar. This defies Rule 1 that states the lag times belong to the predecessor’s calendar. However,

In overall analysis, it can be concluded Project violates the concept of multiple calendar in relationships below:

• Start-Start: positive and negative lag times • Finish-Finish: zero and negative lag times • Finish-Start: positive and negative lag times • Start-Finish: zero and negative lag times

5.4. Flexibilities and Deficiencies of Project and P3

The conclusion of his section serves the secondary objective of comparison between Project and 3P. The aspects that are evaluated are as below.

• Calendars • Activity input and Work Breakdown Structure • Activity linking

In the case of calendars, Project proves to be more functional than P3. Project has an efficient calendar system that allows working hours assigning. This is vital for labor and resource management.

Comparison of Activity ID input between both software packages proves that Project displays a better result. Project’s user-friendliness advantage makes easier data input. In WBS, Project is more suitable for mega-project management because of the fact it offers up to 65000 levels of WBS.

In activity linking, unlike P3, Project displays a warning dialog box to alert the user about conflict in activity linking. However, it is proven in section 4.3.2 that the warning dialog box only appears in Finish-Start with negative lag situations, whereby a number of other miscalculations have been performed by Project. It can conclude that the full reliance on the warning dialog box must be avoided when dealing with multiple calendars.

5.5. Recommendations

The overall conclusion of this paper is that Microsoft Project 2003 generates more miscalculations than Primavera 3.0 in terms of usage of multiple calendars. Preferable software among both would be Primavera 3.0. However, it is advisory to avoid all relationship types with negative lags times and Start-Finish with zero lag time in both software. Extra care must be taken in using multiple calendars in Microsoft Project 2003. Situations as mentioned in section 5.3 must be avoided.

Comparison on overall functions cannot be made since a limited scope of studies is only limited to a few functions. Within the scope studied, Microsoft Project proves to be user-friendly software. It is strongly recommended to the users to take extra precaution on relying to the conflict in linking dialog box when scheduling with multiple calendars.