Start-up Cases Research Articles

R&D Subsidy and Self-Financed R&D: The Case of Japanese High-Technology Start-Ups

This paper examines whether public R&D subsidies constitute a substitute or complement for private-financed R&D. The empirical analysis is based on a panel data of 223 Japanese high-technology start-ups. Our evidence is consistent with the complement hypothesis, i.e., that publicly-funded R&D does promote private R&D. The complement effects are stronger for more mature firms. This is because such firms, in the growth phase, might have greater demands for R&D funds.

`Knowledge management practices' and path-dependency in innovation

There is increasing recognition of the role that ecosystems play in supporting start-ups: particularly start-ups commercializing science-based innovations. In contrast to existing research that tends to focus on established ecosystems, this study uses evolutionary theory to provide a multi-level explanation for the emergence of nascent ecosystems. We employ a qualitative process-based methodology to investigate eight cases of science-based start-ups and their entrepreneurial ecosystems. Our empirical study allowed us to identify a range of retention mechanisms which enable the ecosystem to develop over time – but also, countervailing forces in the form of dissipative processes. Our theoretical contribution is a process model of entrepreneurial ecosystem emergence that makes explicit how retention and dissipation are simultaneous processes. Our model demonstrates the potential of evolutionary theory to understand the interdependence of firm-ecosystem development over time.

Evaluation of a three-state adaptive sample size X control chart

A three-state adaptive sample size control chart is developed and its performance is compared with the standard Shewhart control chart and a two-state adaptive sample size control chart. In general, significant improvements in shift detection capability results from using an adaptive sample size control chart, and the threestate adaptive control chart is superior to the two-state adaptive control for small shifts in the process mean. The improvements found in the two-state and threestate adaptive control chart schemes are gained without increasing the average incontrol sample size over the standard non-adaptive Shewhart control chart. The three-state procedure is only slightly better than the two-state scheme, and so the two-state scheme is likely adequate in most applications. The three process monitoring techniques are compared using both steady-state and start-up cases.

Operational design for start-up of chemical processes

Aiming at designing more operable chemical processes, this paper presents an operational design methodology for the case of process start-up which evaluates and improves a process flow diagram (PFD) into an operational flow diagram (OFD) by modifying the process structure, adjusting the process behavior and adding more facilities. An important controlled group unit (CGU) concept is introduced, which can be operated independently from other parts of the process. This CGU concept makes it convenient to decompose the whole process into CGUs so that the complicated design problem can be narrowed down and simplified. A multi-level blackboard architecture is used to implement such a design methodology which supports an interactive environment for engineers. Object orientation is used to implement the knowledge sources which improves the blackboard performance. Finally, the methodology is illustrated by a simple example and then is evaluated by an industrial hydrogen-desulfurization process design case study.

Method for the Probabilistic Failure Analysis of a Man-Machine System

Summary Probabilistic failure analyses of complex installations are usually made for a plant in a steady state. The current techniques are however too limited for non-steady state situations (e.g. in case of start-up of a plant). This paper will present a possible technique for evaluating the safety of a man-machine system that is brought to another state for which procedural actions have to be performed. It consists of combining a method for the identification of the systems states that may occur due to human errors in following the procedure incorrectly and a systems analysis of these system states. An example related to a man-machine system for locking out electrical power for maintenance is presented.

Investigation of the steady state and transient performance of a reciprocating chiller equipped with an electronic expansion valve

This paper presents the results of experimental investigations into the performance of a chiller equipped with an electronic expansion valve under steady state and transient conditions. The tests were carried out in the laboratory on a 25kW nomimal capacity chiller both during cold start and hot start. For both start-up cases, the response of the chiller in terms of cooling capacity is very fast, leading to low on/off cycling losses. The superheat setting of the expansion valve influences both the transient and steady state performance of the chiller. Optimum refrigerant flow control can be achieved by integrating the control of the expansion valve into an overall microprocessor-based control strategy for the chiller.

The exact multi-period mean-square forecast error for the first-order autoregressive model

The finite-sample behaviour of the multi-period least-squares forecast is considered in the simple normal autoregressive model y t = βy t –1 + u t where ‖ β‖ < 1. Necessary and sufficient conditions are established for the existence of the forecast bias and the mean-square forecast error (MSFE) and an exact expression for the MSFE is given. Exact numerical results are obtained for both the stationary and the fixed start-up case. Our main conclusions are that for small values of β the MSFE is a decreasing function of the number of forecast periods, and that the behaviour of the MSFE in the stationary and the fixed start-up case is very similar, except for values of ‖ β‖ close to 1.

Dynamic Simulation of Shell-and-Tube Heat Exchangers

The transient operation of a multipass shell-and-tube heat exchanger with baffles is described by a multicell dynamic model where every cell represents a specific part of the exchanger. The proposed modeling technique can be used in a digital computer for the dynamic simulation of almost any type of shell-and-tube heat exchanger. The model includes time-dependent inlet conditions for both the cold and the hot streams. Hence, a number of start-up cases can be simulated and, once the system reaches a stationary operating point, a disturbance can be introduced in the inlet temperatures or the flow rates. This particular feature makes the model very useful not only for design purposes but also for transient analysis and control system design.