Examining Interactions Between Solution Architecture and Designer Mistakes

2010 ◽  
Author(s):  
Erich Devendorf ◽  
Kemper Lewis
Keyword(s):  
Design Process ◽  
Optimization Problem ◽  
Solution Process ◽  
Unintended Consequences ◽  
Convergence Time ◽  
Distributed Design ◽  
Damping Properties ◽  
Process Architecture ◽  
The Impact

When designing complex systems, it is often the case that a design process is subjected to a variety of unexpected inputs, interruptions, and changes. These disturbances can create unintended consequences including changes to the design process architecture, the planned design responsibilities, or the design objectives and requirements. In this paper a specific type of design disturbance, mistakes, is investigated. The impact of mistakes on the convergence time of a distributed multi-subsystem optimization problem is studied for several solution process architectures. A five subsystem case study is used to help understand the ability of certain architectures to handle the impact of the mistakes. These observations have led to the hypothesis that selecting distributed design architectures that minimize the number of iterations to propagate mistakes can significantly reduce their impact. It is also observed that design architectures that converge quickly tend to have these same error damping properties. Considering these observations when selecting distributed design architectures can passively reduce the impact of mistakes.

The Impact of Process Architecture on Equilibrium Stability in Distributed Design

2011 ◽  
Vol 133 (10) ◽  
Author(s):  
Erich Devendorf ◽  
Kemper Lewis
Keyword(s):  
Solution Process ◽  
System Stability ◽  
System Level ◽  
Design System ◽  
Distributed Design ◽  
General Process ◽  
Architecture Model ◽  
The Stability ◽  
Process Architecture ◽  
The Impact

In distributed design processes, individual design subsystems have local control over design variables and seek to satisfy their own individual objectives, which may also be influenced by some system level objectives. The resulting network of coupled subsystems will either converge to a stable equilibrium or diverge in an unstable manner. In this paper, we study the dependence of system stability on the solution process architecture. The solution process architecture describes how the design subsystems are ordered and can be either sequential, parallel, or a hybrid that incorporates both parallel and sequential elements. In this paper, we demonstrate that the stability of a distributed design system does indeed depend on the solution process architecture chosen, and we create a general process architecture model based on linear systems theory. The model allows the stability of equilibrium solutions to be analyzed for distributed design systems by converting any process architecture into an equivalent parallel representation. Moreover, we show that this approach can accurately predict when the equilibrium is unstable and the system divergent when previous models suggest that the system is convergent.

Examining the Impact of Aggregated Design Impulses on Process Architecture in Distributed Design

2013 ◽  
Author(s):  
Sourobh Ghosh ◽  
Erich Devendorf ◽  
Kemper Lewis
Keyword(s):  
Complex Systems ◽  
Design Process ◽  
Transient Response ◽  
Design System ◽  
Distributed Design ◽  
Slow Convergence ◽  
Stochastic Inputs ◽  
Process Architecture ◽  
The Impact

During the design of complex systems, a design process may be subjected to stochastic inputs, interruptions, and changes. These design impulses can have a significant impact on the transient response and converged equilibrium for the design system. We distinguish this research by focusing on the interactions between local and architectural impulses in the form of designer mistakes and dissolution, division, and combination impulses, respectively. We find that local impulses tend to slow convergence but systems subjected to dissolution/division impulses still favor parallel arrangements. The strategy to mitigate combination impulses is unaffected by the presence of local impulses.

Are We There Yet? Investigating the Role of Design Process Architecture in Convergence Time

2009 ◽  
Author(s):  
Erich Devendorf ◽  
Kemper Lewis
Keyword(s):  
Design Process ◽  
Parallel Architecture ◽  
Convergence Time ◽  
Distributed Design ◽  
Theoretic Approach ◽  
Equilibrium Solutions ◽  
Design Variables ◽  
Decentralized Design ◽  
Time Required ◽  
Process Architecture

In distributed design individual designers have local control over design variables and seek to minimize their own individual objectives. The amount of time required to reach equilibrium solutions in decentralized design can vary based on the design process architecture chosen. There are two primary design process architectures, sequential and parallel, and a number of possible combinations of these architectures. In this paper a game theoretic approach is developed to determine the time required for a parallel and sequential architecture to converge to a solution for a two designer case. The equations derived solve for the time required to converge to a solution in closed form without any objective function evaluations. This result is validated by analyzing a distributed design case study. In this study the equations accurately predict the convergence time for a sequential and parallel architecture. A second validation is performed by analyzing a large number of randomly generated two designer systems. The approach in this case successfully predicts convergence within 3 iterations for nearly 98% of the systems analyzed. The remaining 2% highlight one of the approach’s weaknesses; it is susceptible to numerically ill conditioned problems. Understanding the rate at which distributed design problems converge is of key importance when determining design architectures. This work begins the investigation with a two designer case and lays the groundwork to expand to larger design systems with multiple design variables.

Computer-aided design versus sketching: An exploratory case study

2012 ◽  
Vol 26 (3) ◽  
pp. 317-335 ◽  
Author(s):  
David Veisz ◽  
Essam Z. Namouz ◽  
Shraddha Joshi ◽  
Joshua D Summers
Keyword(s):  
Design Process ◽  
Computer Aided Design ◽  
Mechanical Engineering ◽  
Computer Assisted ◽  
Cad Tools ◽  
Design Project ◽  
Computer Aided ◽  
Aided Design ◽  
The Impact

AbstractThis paper presents a preliminary comparison between the role of computer-aided design (CAD) and sketching in engineering through a case study of a senior design project and interviews with industry and academia. The design team consisted of four senior level mechanical engineering students each with less than 1 year of professional experience are observed while completing an industry sponsored mechanical engineering capstone design project across a 17 week semester. Factors investigated include what CAD tools are used, when in the design process they are implemented, the justification for their use from the students' perspectives, the actual knowledge gained from their use, the impact on the final designed artifact, and the contributions of any sketches generated. At each design step, comparisons are made between CAD and sketching. The students implemented CAD tools at the onset of the project, generally failing to realize gains in design efficiency or effectiveness in the early conceptual phases of the design process. As the design became more concrete, the team was able to recognize clear gains in both efficiency and effectiveness through the use of computer assisted design programs. This study is augmented by interviews with novice and experienced industry users and academic instructors to align the trends observed in the case study with industry practice and educational emphasis. A disconnect in the perceived capability of CAD tools was found between novice and experienced user groups. Opinions on the importance of sketching skills differed between novice educators and novice industry professionals, suggesting that there is a change of opinion as to the importance of sketching formed when recent graduates transition from academia to industry. The results suggest that there is a need to emphasize the importance of sketching and a deeper understanding as to the true utility of CAD tools at each stage of the design process.

Assessing design process in engineering consultancy firms using lean principles

SIMULATION ◽  
2012 ◽  
Vol 88 (12) ◽  
pp. 1522-1536 ◽  
Author(s):  
M Marzouk ◽  
I Bakry ◽  
M El-Said
Keyword(s):  
Design Process ◽  
Comprehensive Model ◽  
Output Analysis ◽  
Lean Principles ◽  
Proposed Model ◽  
Client Request ◽  
Using Data ◽  
Consultancy Firm ◽  
The Impact

The aim of this research is to provide a tool for assessing the impact of applying lean principles to the design process at construction consultancy firms. Through several interviews, a comprehensive model was built to simulate the design process, using data from a leading consultancy firm in Egypt. The model contains the main processes and activities that form different phases of the design process and depicts the interconnectivity of processes and activities needed to create a complete design package upon client request. The research describes how the five main lean principles are integrated in the model. A case study is considered to demonstrate the effect of using the proposed model on the design process and to illustrate how the design process performs differently when lean principles are introduced. Case study output analysis reveals 40% improvement in the lean process performance measured in terms of activity utilization rates.

scholarly journals Understanding the Intersection of Climate/Environmental Change, Health, Agriculture, and Improved Nutrition: A Case Study on Micronutrient Nutrition and Animal Source Foods

2020 ◽  
Vol 4 (7) ◽  
Author(s):  
Daniel J Raiten ◽  
Lindsay H Allen ◽  
Joanne L Slavin ◽  
Frank M Mitloehner ◽  
Gregory J Thoma ◽  
...  
Keyword(s):  
Agricultural Practices ◽  
Unintended Consequences ◽  
Changing Environment ◽  
Animal Source Foods ◽  
Animal Source ◽  
Nutritional Needs ◽  
The Impact ◽  
Global Population

Abstract With a growing global population, the demand for high-quality food to meet nutritional needs continues to increase. Our ability to meet those needs is challenged by a changing environment that includes constraints on land and water resources and growing concerns about the impact of human activity including agricultural practices on the changing climate. Adaptations that meet food/nutritional demands while avoiding unintended consequences including negatively affecting the environment are needed. This article covers a specific case study, the role of animal source foods (ASFs) in meeting micronutrient needs in a changing environment. The article covers our understanding of the role of ASFs in meeting micronutrient needs, evidence-based approaches to the development of nutrition guidance, the current issues associated with the relation between animal production practices and greenhouse gas emissions, and examples of how we might model the myriad sources of relevant data to better understand these complex interrelations.

The Fit Between Spatial Configuration and Idealized Flows: Mapping Flows in Surgical Facilities as Part of Case Study Visits

2020 ◽  
pp. 193758672092835
Author(s):  
Herminia Machry ◽  
Anjali Joseph ◽  
Deborah Wingler
Keyword(s):  
Design Process ◽  
Spatial Configuration ◽  
Healthcare Services ◽  
Design Teams ◽  
Flow Mapping ◽  
Healthcare Facilities ◽  
Mapping Tool ◽  
Mapping Approach ◽  
The Impact

Purpose: This study proposes a flow mapping approach for surgical facilities that can be implemented by design teams as a component of case study tours. Background: The provision of healthcare services involves simultaneous and closely coupled flows of people, objects, and information, and the efficiency of these flows is influenced by the spatial configuration of the buildings where these services are housed. Many architecture firms conduct case study tours to inform their design process. However, these tours often lack a structured way of documenting different flows and interpreting observations. A structured approach is needed during the design process to understand the impact of spatial configuration on healthcare flows. Method: Site tours were conducted at four surgery centers to develop and test an evidence-based flow mapping approach. Idealized flows within surgical facilities were first identified from the literature, followed by the development of a data collection tool aimed at documenting these flows in each case study through a pre-assessment questionnaire, a physical assessment, and interviews with staff. Results: The flow mapping tool kit was effective in allowing the design team to systematically understand the physical configuration of surgical flows across case studies. The tool also allowed the team to identify spatial configuration characteristics acting as barriers and facilitators to idealized flows. Conclusions: The flow mapping approach was able to provide structure for conducting these short tours more effectively via observations and staff inquiry, enabling design teams to draw more meaningful conclusions from case study tours and conduct comparisons between healthcare facilities visited.

Exploring the effectiveness of parallel systems in distributed design processes subjected to stochastic disruptions

2014 ◽  
Vol 28 (4) ◽  
pp. 399-412 ◽  
Author(s):  
Sourobh Ghosh ◽  
Erich Devendorf ◽  
Kemper Lewis
Keyword(s):  
Design Process ◽  
Transient Response ◽  
Parallel Systems ◽  
Design System ◽  
Distributed Design ◽  
Slow Convergence ◽  
Statistical Support ◽  
Design Case ◽  
Design Case Study

AbstractDuring the design of complex systems, a design process may be subjected to stochastic disruptions, interruptions, and changes, which can be described broadly as “design impulses.” These impulses can have a significant impact on the transient response and converged equilibrium for the design system. We distinguish this research by focusing on the interactions between local and architectural impulses in the form of designer mistakes and dissolution, division, and combination impulses, respectively, for a distributed design case study. We provide statistical support for the “parallel character hypothesis,” which asserts that parallel arrangements generally best mitigate dissolution and division impulses. We find that local impulses tend to slow convergence, but systems also subjected to dissolution or division impulses still favor parallel arrangements. We statistically uphold the conclusion that the strategy to mitigate combination impulses is unaffected by the presence of local impulses.

scholarly journals A Quadratically Constrained Optimization Problem for Determining the Optimal Nominal Power of a PV System in Net-Metering Model: A Case Study for Croatia

Energies ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1746
Author(s):  
Luka Budin ◽  
Goran Grdenić ◽  
Marko Delimar
Keyword(s):  
Optimization Problem ◽  
Net Present Value ◽  
Electrical Energy ◽  
Electricity Production ◽  
Discrete Optimization Problem ◽  
Pv System ◽  
Net Metering ◽  
Quadratically Constrained ◽  
The Impact

The world’s demand for electrical energy is increasing rapidly while the use of fossil fuels is getting limited more and more by energy policies and the need for reducing the impact of climate change. New sources of energy are required to fulfill the world’s demand for electricity and they are currently found in renewable sources of energy, especially in solar and wind power. Choosing the optimal PV nominal power minimizes the unnecessary surplus of electrical energy that is exported to the grid and thus is not making any impact on the grid more than necessary. Oversizing the PV system according to the Croatian net-metering model results in switching the calculation of the costs to the prosumer model which results in a decrease of the project’s net present value (NPV) and an increase in the payback period (PP). This paper focuses on formulating and solving the optimization problem for determining the optimal nominal power of a grid-connected PV system with a case study for Croatia using multiple scenarios in the variability of electricity production and consumption. In this paper, PV systems are simulated in the power range that corresponds to a typical annual high-tariff consumption in Croatian households. Choosing the optimal power of the PV system maximizes the investor’s NPV of the project as well as savings on the electricity costs. The PP is also minimized and is determined by the PV production, household consumption, discount rate, and geographic location. The optimization problem is classified as a quadratically constrained discrete optimization problem, where the value of the optimal PV power is not a continuous variable because the PV power changes with a step of one PV panel power. Modeling and simulations are implemented in Python using the Gurobi optimization solver.

scholarly journals A case study of secondary school leaders' perceptions of attendance policies and procedures used to increase attendance

2018 ◽  
Author(s):  
◽  
Mark A. Bullimore
Keyword(s):  
School Improvement ◽  
Family Relationships ◽  
School Leaders ◽  
Unintended Consequences ◽  
Accountability Standards ◽  
Community Awareness ◽  
Awareness Programs ◽  
The Impact ◽  
Attendance Policies

Nationwide, pressures from outside influences such as politicians and educational policy makers are placing schools in precarious situations to make drastic changes in attendance policies to meet state accountability standards. The researcher used interviews and a focus group with school leaders, and archival data to find common themes which were then viewed through the conceptual underpinning of accountability. This case study adds to the field of education a deeper understanding of school leaders' perspectives on the impact attendance accountability standards have on the overall effectiveness of school improvement. The findings suggest: the new proportional attendance policy is detrimental to a school leaders' ability to focus on other school improvement practices while creating negative unintended consequences for schools and students; incentives and punitive consequences have short-term success while decaying school-family relationships; and district-wide and community awareness programs seemed to have the greatest impact on long term attendance improvement. Based on these findings, the following three practices should be implemented by districts: Systematic monitoring of attendance data, the use of low cost incentives and simple rewards, and the implementation of district-wide engagement and education of family and community awareness programs.

Sign in / Sign up

Export Citation Format

Share Document