J. David Porter

A Procedure for Smooth Implementation of Activity-Based Costing in Small Companies

Abstract: This article describes a procedure that allows companies to easily switch from a traditional costing system to an activity-based costing (ABC) system. The procedure is particularly useful to small companies (less than 100 employees) for which the standard implementation of ABC is too expensive and complex. The method, which consists of eight easy-to-follow steps, leads a company through the Coopers two-stage activity-based costing model. At first, decision makers determine cost information, which can be obtained via an educated guess, a systematic appraisal, or actual data collection. The method used to collect the data would depend on the level of accuracy desired and the amount of money assigned to this endeavor. Next, the overhead expenses such as administration, rent, utilities, and transportation are compiled into product cost information using newly developed matrices. Using these matrices, cost-related calculations become easy and overhead costs are traced without difficulty to the cost objects in the final step. The ease of use of the proposed procedure is illustrated using actual data from a small manufacturing company located in western Pennsylvania.

A standard test protocol for evaluation of radio frequency identification systems for supply chain applications

In this research, a test protocol was developed and validated with eight different radio frequency identification (RFID) systems. These systems were evaluated with respect to basic performance parameters in their abilities to carry out shipping and receiving operations in the warehouse receiving process. Two major categories of tests were administered: laboratory baseline performance tests and warehouse passive interference tests. The protocol evaluated RFID systems on such performance characteristics as the effective capture zone, tag orientation requirements, tag separation requirements, performance on conveyors and forklifts, performance when covered by stretch wrap or shrink wrap, performance when attached to different types of containers containing different types of solid materials or liquids, and so forth. Results of this research showed that one of the systems was able to meet several of the requirements for shipping and receiving in a warehouse environment, but none of the systems was able to meet all of the requirements for performance in this application. Additionally, the test protocol and results led to the adoption of a UHF frequency (915 MHz) as the American National Standard for passive RFID systems.

Antenna Characterization for Bluetooth-Based Travel Time Data Collection

Several approaches for travel time data collection based on the reading of time-stamped media access control addresses from Bluetooth-enabled devices have been reported in the literature recently. This new approach offers a number of advantages over more conventional methods, including lower costs of hardware and software, the volume of data that can be collected over time, and ease of implementation. A fundamental component that may affect the quantity and the quality of the travel time samples collected with a Bluetooth-based system is the antenna type utilized. Antenna characteristics such as polarization and gain must be matched to specific application environments to optimize the performance of a Bluetooth reader unit. However, experimental data that focuses on antenna characterization as it relates to the use of Bluetooth technology to assess the performance of transportation facilities is lacking. In this study, five different types of antennas were characterized to assess their suitability to support a Bluetooth-based travel time data collection system. The results indicate that vertically polarized antennas with gains between 9dBi and 12dBi are good candidates for travel time data collection. Also, different antenna types are better suited to different uses of the Bluetooth-based system. If the main focus is the collection of travel time data, then an antenna with a lower sampling rate may provide more accurate travel time samples.

Laser Direct-Part Marking of Data Matrix Symbols on Carbon Steel Substrates

Certain applications have recently appeared in industry where a traditional bar code printed on a label will not survive because the item to be tracked has to be exposed to harsh environments. Laser direct-part marking is a manufacturing process used to create permanent marks on a substrate that could help to alleviate this problem. In this research, a 532 nm Nd:YAG laser was utilized to produce Data Matrix symbols onto carbon steel substrates. The quality of the laser marked Data Matrix symbol was then evaluated according to the ISO/IEC 16022 bar code technology specification for Data Matrix. Several experiments were conducted to explore the effects that different parameters have on the quality of the laser direct-part marked symbols. Parameters such as type of carbon steel, percent of laser tool path overlap, profile speed, average power, and frequency were found to have significant effects on the quality of the Data Matrix symbols produced with the laser. The analysis of the results indicated that contrast and print growth were the critical ISO/IEC 16022 standard performance measures that limited the laser marked Data Matrix symbols from achieving a higher final grade.

Effect of active interference on the performance of radio frequency identification systems

Recent advancements in wireless technology have resulted in an unprecedented demand for Radio Frequency (RF) spectral resources. Increasing frequency reuse also increases RF interference, which decreases a systems capacity and/or service quality. The primary focus of this research was the development of a test protocol for the characterisation of the performance of Radio Frequency Identification (RFID) systems when active interference was present. The test protocol was comprised of four different experiments: Jamming on Central Frequency of Operation, Apply Full Range of Frequencies in Sweeps, Modulating the Jamming Signal and Tag Pollution. The effectiveness of the test protocol was verified by fully characterising eight RFID systems operating at frequencies that ranged from 120 kHz to 2.45 GHz. The performance measure of read rate was utilised to assess whether or not the jamming signal had an effect on the performance of the RFID systems. The results obtained through actual experimentation, as well as the validation by experts in the RFID field, indicate that the approach described in this research is viable and useful for both manufacturers and users of RFID technology.

Technology Evaluation of Oregon’s Vehicle-Miles-Traveled Revenue Collection System: Lessons Learned

Many states in the United States rely on fuel taxes to maintain roads. In 2005 eighty percent of Oregons road revenues depended either directly or indirectly on fuel taxes. However, Oregon has seen this flow of revenue slowly decline during the past 30 years. It is envisioned that further improvement of automobile fuel efficiency will have an even more dramatic effect on fuel tax revenues in the near future. In 2001 the Oregon Legislative Assembly passed House Bill 3946 mandating the Oregon Department of Transportation to examine alternatives to the current system of taxing highway use through fuel taxes. Since 2003 Oregon State University, in collaboration with the Oregon Department of Transportation and the Road User Fee Task Force, has investigated a vehicle miles traveled (VMT)-based alternative to the fuel tax. The design, development, and testing of the VMT-based solution was broken down into several phases, the last of which required the execution of a pilot test from June 19, 2006, to March 25, 2007, involving approximately 250 volunteer drivers. The main objectives of this paper are to present the technology performance results of the VMT-based solution gathered during the pilot test and to share the lessons learned from its subjective evaluation.

Cost Drivers in Microlamination Based on a High-Volume Production System Design

The purpose of this research is to develop a cost estimation model in an attempt to begin exploring the current cost drivers for microlamination. To do this without actual cost information, a production system design is proposed for the high-volume production of MECS devices. Constraints on this facility are that it produces microlaminated structures from stainless steel diffusion bonding. Also, a cost estimation model is developed based on the known cycle time and capital equipment costs from the production system design. Finally, a sensitivity analysis is performed to determine the cost drivers under different market and product scenarios. Results from the sensitivity analysis indicated that device size and production rate do have an effect on the overall manufacturing cost of microlamination devices. Therefore, it is concluded that the emphasis of future research in metallic microlamination should focus on bonding larger laminae and in reducing both cycle time and warpage.Copyright

Improving Accuracy and Precision of Travel Time Samples Collected at Signalized Arterial Roads with Bluetooth Sensors

Time-stamped, media access control addresses, acquired from Bluetooth-enabled devices to collect travel time data, have received significant attention in the past few years. Research has focused mainly on the application of Bluetooth technology to obtain travel time data on freely flowing roads. A few studies have addressed the use of Bluetooth data collection systems on arterial roads, particularly with respect to travel times between signalized intersections, with questionable accuracy. The objective of this research was to develop a methodology to collect accurate and precise travel time data between signalized intersections, with the use of a data collection system that had a Bluetooth basis. The developed methodology utilized received signal strength indicator (RSSI) data to improve signifi-cantly the accuracy of intersection-to-intersection travel time samples. Test results on a busy arterial road showed that the travel time samples generated with the RSSI method were significantly better (i.e., had less error) than the travel time samples calculated with other methods reported in the literature. The proposed RSSI travel time data collection method could be implemented with any wireless technology that provided a unique identification number to distinguish between different mobile devices and an associated signal strength measurement during the wireless communication process.

Artificial Neural Network Approach to Data Matrix Laser Direct Part Marking

Certain applications have recently appeared in industry where a traditional bar code printed on a label will not survive because the item to be tracked has to be exposed to harsh environments. Laser direct-part marking is a manufacturing process used to create permanent marks on a substrate that could help to alleviate this problem. In this research, artificial neural networks were employed to model the laser direct-part marking process of Data Matrix symbols on carbon steel substrates. Several experiments were conducted to study the laser direct-part marking process and to generate data to serve as training, validation and testing data sets in the artificial neural networks modeling process. Two performance measures, mean squared error and correlation coefficient, were utilized to assess the performance of the artificial neural network models. Single-output artificial neural network models corresponding to four performance measures specific to the Data Matrix bar code symbology were found to have good learning and predicting capabilities. The single-output artificial neural network models were compared to equivalent multiple linear regression models for validation purposes. The prediction capability of the single-output artificial neural network models with respect to laser direct-part marking of Data Matrix symbols on carbon steel substrates was superior to that of the multiple linear regression models.

Performance evaluation of heterogeneous wireless local area networks

The overall market for wireless local area networks (WLANs) grew more than 200% from 2000 to 2002, and will continue to grow at a compound annual growth rate of 23% until 2007. The objective of this research was to assess the performance of commercial-off-the-shelf WLAN systems with respect to interoperability, roaming ability, power consumption, throughput, and range. The evaluation was performed on both homogeneous and heterogeneous WLAN systems. Experimental test results indicate that the fundamental components of a WLAN system (i.e. access points and radio cards) and their combinations, significantly affect performance with respect to range, throughput, and power consumption. No significant differences in performance were observed in the WLAN systems with respect to interoperability (i.e. all systems characterized proved to be fully interoperable) or roaming (i.e. all combinations of access points and radio cards were able to seamlessly roam).