bluuebunny/crossref_metadata_2025 huggingface dataset:
Political fragmentation of the Dutch Windward Islands
Authors: Kersell J. E.
Published: July 2007

The Dutch Windward Islands are examined to see if they throw any light on the problems experienced when very small island communities try to come together to form a larger political unit. The Constitution of 1954, though federal in intent, was unitary in practice, with the main island, Curacao treating the others like municipalities. However the island authorities are capable of asserting themselves against the centre. They control implementation, raise revenue and receive local political support. Because of the small size of the populations and civil services involved, island and federal officials collaborate harmoniously. Leading individuals are important for development, notably St Maarten's Claude Wathey. New initiatives also require effective negotiations to deal with off‐shore tourist organizations. However, there is little significant industry beyond tourism. In 1988 the three Dutch Windward Islands agreed to co‐operate with each other. Decentralization within the largest island could help this cooperation as could a regional association along the lines of the South Pacific Forum.
Institutional reform in Nigeria
Authors: Phillips Adedotun O.
Published: July 2007

The Nigerian military government set up a panel in 1985 to reform the Federal Civil Service. This panel discovered the following weaknesses, among others: lack of measurable objectives; inadequate evaluations; mismanagement of time; inadequate facilities; disorganization; personnel mismanagement; and overcentralization. It proposed a number of measures to deal with these weaknesses including: decentralization; reorganization; professionalization; more careful evaluations; and appropriate incentives. While these proposals remain unimplemented, structured regular reviews of the civil service should continue.
Decentralizing water supply services in developing countries: Factors affecting the success of community management
Authors: Rondinelli Dennis A.
Published: July 2007

This article examines the problem of extending access to potable water through conventionally controlled government services and describes the roles of non‐governmental organizations and community management associations in improving service delivery and maintaining local water systems. Six sets of factors that are crucial to the success of community management are identified: adequate incentives, sufficient skills and resources, appropriate processes for water systems operations and maintenance, effective interorganizational relationships, appropriate technology, and effective systems of monitoring, evaluation and feedback. The components that must be taken into consideration in designing and implementing programmes for decentralizing water supply systems through community management are set out.
From processing to analysing: Intensifying the use of microcomputers in development bureaucracies
Authors: Peterson Stephen B.
Published: July 2007

This article examines constraints in development bureaucracies in intensifying the use of microcomputers as they move beyond processing applications to analysing applications. The work is based on the experience of several ministries of the Government of Kenya. Processing applications involve throughput of data and are relatively simple. Analysing applications, in contrast, are more complex and include data assembly, sensitivity analysis, and modelling. The article argues that processing applications are more compatible with the administrative cultures, bureaucratic functions, personnel skill levels and organizational structures of development bureaucracies. Analysing applications are less compatible because they require a level of training and motivation uncommon in development bureaucracies. Analysing applications are further thwarted by constraints in the supply of relevant information and the lack of demand for analysis by decision‐makers. A four‐cell matrix is developed which explains these constraints. The article concludes with several recommendations for encouraging microcomputer‐based analysis, but cautions that processing applications will continue to dominate for the foreseeable future.
Leadership resistance to the implementation of new ideas acquired through training in the Nigerian civil service
Authors: Maduabum Chuks P.
Published: July 2007

Staff training and development have received such widespread attention in the Service that it can be safely said that it has become a way of life of Nigeria's federal bureaucracy. We posit, however, that these efforts will not achieve the desired results if ample opportunities are not provided for the trained to apply skills and ideas acquired from their training. The efforts of those who are their superiors and can thus encourage the implementation of new ideas are the subjects of this study. A survey was conducted of 300 trained officers, and 60 Departmental Training Officers (DTOs) in the Nigerian Civil Service. The emerging data were computer‐processed and analysed using 2‐variable chi‐square (χ2) statistics and Pearson's correlation coefficient (r). The findings are that superior officers generally tend to resist innovative ideas emanating from their trained subordinates. However, where superior and subordinate officers are similarly exposed to a training course the tendency is for the superior officer to support the implementation of ideas acquired from the course. To improve the situation, therefore, we prescribe: (a) the expansion of training activities so that more staff can benefit; and (b) the creation of opportunities for the trained to occupy senior positions in the Service.
Poverty and profit in Central American forest policies
Authors: Guess George M.
Published: July 2007

The failure of forestry to contribute to poverty reduction in Central America is due to public policies which inhibit its profitability. Absence of public regulation of harvesting and competing subsidies to agriculture keep forestry stumpage prices artificially low. This encourages destruction of the forest resource, which damages both the environment and the potential to reduce poverty. A comparison of Costa Rica and Honduras reveals two dissimilar approaches toward forest policy. While Costa Rica attempts to raise producer and grower stumpage prices by tax credits, soft loans and differential species fees, Honduras enforces price ceilings and uses centralized authority to control forest production and export. Both countries exhibit weaknesses in the management control cycle of programming, budgeting, implementing and evaluating their forest policies. Yet the Costa Rican approach has increased stumpage prices already, which bodes well for their forest sector. By contrast, the major beneficiary of Honduran forest policy has been COHDEFOR, the state enterprise responsible for forestry management, controlling production, and running its national system of agroforestry cooperatives. Despite greater public authority and resources than the Costa Rican forest service (DGF), the Honduran forest policy is not likely to increase producer profitability or reduce poverty in the near future.
Determinants of success in African local governments: An overview
Authors: Olowu Dele , Smoke Paul
Published: July 2007

A potentially useful method for determining how to design viable and competent local government systems is to examine local authorities that function effectively. This paper synthesizes the major findings of seven case studies of ‘successful’ local governments in Sub‐saharan Africa, highlighting the principal factors contributing to their success and exploring ways in which they could further improve their performance. The determinants of success identified in the studies include: location in an area with an adequate economic base; well‐defined responsibilities in a satisfactory legal framework; capacity to mobilize sufficient resources; supportive central government activities; and appropriate management practices, including development of productive internal and external relations and satisfactory responsiveness to constituents. All of these factors are considered to be necessary, but none is independently sufficient to guarantee success, which is a multidimensional and cumulative process of achievement.
Zambia's local administration act, 1980: A critical appraisal of the integration objective
Authors: Mukwena Royson M.
Published: July 2007

In 1980 administrative reforms were announced in Zambia which aimed at integrating the party, central government departments, and local authorities. Over 10 years have now elapsed since the announcement of the reforms and to date the envisaged integration has not been realized. The problems and prospects of the envisaged integration are examined. Integration has not been possible due to lack of a formula for it. It is not possible in an atmosphere where the District Council operates without a Development Plan whilst the various central government departments and agencies follow their own plans. The real aim of the integration was to revive the demoralized and ineffective UNIP organization at grass‐roots level. The dysfunctions of political control in the Zambian context are examined. What local councils, central government departments and parastatals require is coordination and not integration with the party or an increase in political control. The reintroduction of multi‐partyism has improved the prospects for this development.
Creating a national NGO council for strengthening social welfare services in Africa: Some organizational and technical problems experienced in Malawi
Authors: Simukonda H. P. M.
Published: July 2007

In 1985, Malawi's social welfare organizations formed the Council for Social Welfare Services in an attempt to strengthen the delivery of social welfare services to the underprivileged. This was to be achieved with more formalized, co‐ordinated functioning among organizations and a better system for assessing the technical, financial and training needs of the organizations and the population and for meeting them. This paper examines the feasibility of finding such an organization that works. It focuses on problems such as the heterogeneity of social welfare organizations in terms of origin, objective guidelines and operational cultures, as well as the feasibility of getting the necessary co‐operation to strengthen the council's resource and authority capacity to meet its own objectives. The overall view in this paper is that the council has a long way to go before it achieves the situation for which it stands, if that is at all possible, because of the idiosyncratic nature of social welfare organizations.
Towards a stages theory approach to privatization
Authors: Odle Maurice
Published: July 2007

In analysing the path of optimal sequencing of privatizations by public administrations, it is too simplistic to characterize the process as one in which in the early phase small state‐owned enterprises are disposed of and, in the later stage, the larger enterprises. Such a dichotomy fails to capture fully the market failure elements, technological dimensions, sociological imperatives and political constraints that help to determine the choice and timing of enterprises to be privatized. Rather, the privatization experience of the developing and developed countries, including the former centrally planned economies, can be eclectically analysed as traditional, transitional and transformation stages in an almost inexorable movement towards a pure capitalist economy. In the traditional stage, countries have tended to privatize those enterprises for which the private sector has an obvious comparative advantage. In the transitional stage, the privatization programme includes certain important enterprises, which, despite a considerable amount of government subsidy or tariff protection, have performed ‘inefficiently’. In the stage of transformation from a still basically mixed economy to a near pure capitalist economy, there is privatization of the strategic enterprises. Although the stages approach varies between countries, the above‐mentioned sequencing allows for more effective cumulative internalization of the learning experience.
Revitalizing public management training in the Americas
Authors: Graham Lawrence S.
Published: July 2007

The decade of the 1980s signalled major changes within public administration and development‐oriented activities. As a consequence of the internationalization of the agendas of practitioners and academics working in these areas, there is today a growing convergence among public policy, public management, public administration and political science. Given the complexity of the public sector cross‐nationally, what has become necessary in public management education is the design of programmes that meet specific needs and priorities and which are responsive to very different national settings. This particular case study is centred around one endeavour to achieve more effective interfacing between theory and practice, in the teaching of public management and the design of development programmes in the United States (US). It is based on an assessment of a 10‐year co‐operative endeavour between the National Association of Schools of Public Affairs and Administration and the US Agency for International Development. The outcomes of this project provided not only leverage for important changes in the teaching programmes of schools concerned with international management education but also built a new relationship between government and a non‐governmental organization through the contacting out of management development work.
The evolutionary life cycles of non‐governmental development organizations
Authors: Avina Jeffrey
Published: July 2007

This article argues that non‐governmental organizations (NGOs) active in community development exhibit different organizational characteristics at different phases of their evolution. Being able to recognize the characteristic descriptive elements of the different phases of organizational development better positions one to understand the nature of an NGO's relationship with donors, beneficiaries and the world around it. Perhaps more importantly, recognizing what phase of its organizational development cycle an NGO is in will assist the practitioner to understand the types of problems the NGO may be facing, their cause and the range of options available for problem resolution.
Institutional development in World Bank projects: Analytical approaches and intervention designs
Authors: Brinkerhoff Derick W.
Published: July 2007

This article examines a random sample of World Bank projects in order to identify the methods of institutional analysis (IA) and resulting institutional development (ID) strategies employed. The findings confirm impressionistic data which indicate that IA in World Bank projects is highly standardized, and concentrates on factors internal to the organization at the expense of external environmental factors, particularly as these are reflected in the needs of stakeholders and customers. ID is an integral part of most Bank projects, and the trend is shown to be towards increasing attention to ID. The nature of ID in World Bank projects reflects the inward orientation of IA, with strong emphasis given to training and development as a standard solution. It is concluded that IA and ID which are broader in scope will improve project design and impact.
Post‐communist transition of local government in Hungary: Managing emergency social aid
Authors: Fábián Katalin , Straussman Jeffrey D.
Published: July 2007

Tensions are embedded in post‐communist transitions. Public policies exhibit the disharmony between two different and often competing objectives: (1) developing a fully operational market economy within a democratic context and (2) maintaining social protections in the form of a wide array of social benefits. One challenge for post‐communist regimes is the management of this tradeoff. This challenge is observed through an analysis of the administration of emergency social aid in Hungary.

The analysis shows that post‐communist transitions, as exemplified by the efforts to build local government capacity in Hungary, experience problems of sequencing. In particular, equity decisions are difficult to manage not only because they have their roots in socialist ideology and the policies of the former regime, but also because the increasing number of vulnerable populations makes welfare considerations a politically sensitive task now more than ever before. Meanwhile, the institutional processes needed to manage tensions are fluid and immature. Ultimately the success of the post‐communist transition in Hungary (and elsewhere in Central and Eastern Europe) will be measured by the ability to build institutions that can manage and consolidate political pressures.
The practice of regional development in Indonesia: Resolving central‐local coordination issues in planning and finance
Authors: Crane Randall
Published: July 2007

Renewed interest by the Indonesian government in decentralization and cost‐recovery practices has led to both real and illusory reforms, though the distinction between the two is often not clear. This is particularly true with respect to infrastructure planning and finance. Recently, the allocation criteria for capital grants to local governments have been substantially revised, nearly every year, to reflect long lasting concerns regarding differences in interregional development needs and resources. In addition, the level of funding for local government investment has risen dramatically to support increased local responsibility in planning. Most development spending does not pass through local budgets, however. In either case, the project planning process has remained firmly under the direction of the central government's technical ministries.

Infrastructure investment thus tends to be segmented, not only by sector, but also by funding source. The rate at which these two factors balance off in current practice does not indicate a strong commitment to effective decentralization. The article suggests that greater regional government participation in the national planning process would be beneficial. To deal with the fragmented nature of sectoral planning is more problematic, as a more integrated approach would in the long term require either a new layer of bureaucracy or a substantial reorganization of the technical ministries. In the shorter term, a gradual shift toward general purpose grants would also generate regional development plans more consistent with the goals of decentralization while maintaining substantial central control and oversight.
Hochenergieverhalten von Streuamplituden in der Störungstheorie und im multiperipheren Modell
Authors: Sommer G.
Published: July 2007

A review is given of theorems and models for the high energy behaviour of scattering amplitudes. Furthermore it is shown that the scattering amplitude at extremely high energies cannot be approximated only by the sum of ladder graphs. By substitution of some of the ladder “rungs” by special subgraphs, we find after summing up a scattering amplitude asymptotically larger than the original one. Especially, the sum of all “ladder diagrams with two crossed rungs” exceeds the ladder approximation of the Bethe‐Salpeter equation by a factor proportional to the logarithm of the energy. This result is true as well in perturbation theory for A3‐coupling as in the framework of the Amati‐Fubini‐Stanghellini model. As a consequence asymptotically the total cross section in the multiperipheral model is not given by the imaginary part of the sum of ladder graphs, but all permutations of the multiperipherically produced particles are important at high energies.
Polarized Proton Targets and Low‐Energy Nucleon‐Nucleon Experiments
Authors: Lehar F. , Winternitz P.
Published: July 2007

The possible use of a polarized proton target in the investigation of low‐energy nucleon‐nucleon interactions is reviewed. The reconstruction of the scattering matrix and verification of P‐, T‐and isotopical invariances are briefly discussed. Possible sources and detectors of polarized particles are considered. The problem of phase‐shift analysis and nucleon‐nucleon potentials are treated in the appendices. Tables of experimental values are given for the polarization of nucleons scattered on nucleons. Experimental quantities determined from the phase‐shift analysis are given in graphs for the energies 14.5 and 23.1 MeV.
On the Renormalization of Feynman Integrals
Authors: Westwater M. J.
Published: July 2007

An arbitrary Feynman integral is considered for external momenta in the Euclidean region, the usual rotation of energy contours having been used to write the integral as an integral over Euclidean internal momenta. A compactification of the space of internal momenta is defined, and the Feynman integral is written as the integral of a current on this compact manifold. This presentation of the integral is used to give a proof of the convergence criterion for Feynman integrals, and to show that a well‐defined renormalized integral may be obtained by a subtraction operation or by analytic renormalization.
Thermodynamics under Dynamic Forcing
Authors: Kohler R. H.
Published: July 2007

Beginning with a system that is governed by an arbitrary time‐dependent Hamiltonian, we exhibit an existence proof for a unitary generator that has an arbitrary initial value and yet contact transforms the representation to one governed by any given kinematically equivalent Hamiltonian. By choosing the initial value of the unitary operator to be unity, we are able to compare the behaviour of the same system under two different Hamiltonians and the same initial state vector. We thus are able to establish that the eventual physical states evolving from two distinct initial quantum state vectors will become practically indistinguishable under one of the two Hamiltonians if and only if they do so under the other. For the restricted class of systems for which one of the two Hamiltonians is a time‐independent energy operator, and also generates equilibrium thermodynamics, then the condition for merging under the time‐dependent Hamiltonian is the same as under the time‐independent one. The two states must have the same initial energy. As a special case of the above, we choose the time‐independent Hamiltonian to be the relativistic energy measuring operator for the time‐dependent Hamiltonian, as associated with the chosen initial time. If the system under the time‐dependent Hamiltonian is such that its relativistic energy measuring operator for any fixed time generates equilibrium thermodynamics, then we are led rigorously to the conclusion that the instantaneous relativistic energy for the system under the time‐dependent Hamiltonian is simply a well‐defined function of time and depends only on the initial energy and not on any other initial conditions. For a composite system that is of the above type, and in addition consists of one very small system in contact with a very large one, which is called a generalized reservoir, we consider a specific initial physical state for the large system, and various states for the small one. The eventual dynamic state of the composite system is essentially independent of the initial state of the small system which has almost no influence on the total composite energy. Hence the eventual dynamic state of the small system is shown rigorously to be independent of its initial state. For a forced system with a time‐dependent Hamiltonian, we discuss the assignment of equilibrium thermodynamic potentials to a representation with a time‐independent Hamiltonian. We discuss the concept of a process under a time‐dependent Hamiltonian. Such a process is a natural generalization of the static and quasi‐static processes. Also, we verify all of the theory with both general and specific examples of electromagnetic interactions.
Lorentz Covariant Wave Functions and Equations for Elementary Systems
Authors: Fonda Luciano , Ghirardi Gian Carlo
Published: July 2007

We give in this paper a detailed and unified description of the procedures which must be followed for all cases of physical interest to go from the wave functions carrying an irreducible representation of the restricted Poincaré group, to objects having a manifestly covariant behaviour. As well known, for instance for the case of spin 1/2 massive particles, this amounts to performing the inverse of a Foldy‐Wouthuysen transformation.

Before coming to the main subject of the paper, the construction of the irreducible representations of the restricted and extended Poincaré group are reviewed. Particular emphasis is given to the physical meaning of the representations and of the invariants which characterize them. After this, we derive manifestly covariant quantities from the wave functions of the irreducible representations of the restricted group for spin 0. 1/2 and 1, massive and massless elementary systems. The corresponding relativistically invariant equations, i.e. the Klein‐Gordon, Dirac, Proca, Weyl and Maxwell equations are then derived. The transformations properties under the transformations of the extended group are also extensively discussed.
On the Hamiltonian of the Cubic Boson Selfinteraction in Four Dimensional Space Time
Authors: Osterwalder Konrad
Published: July 2007

In four dimensional space time a boson field with cubic selfinteraction is considered. It is shown, that if a space cutoff function is included in the interaction term, the renormalized Hamiltonian Hren exists as a densely defined symmetric operator.
Messungen der Phasendifferenz ϕ+− zwischen den Amplituden der Zerfälle KL → π+π− und KS → π+π− und Modelle der CP‐Verletzung
Authors: Kleinknecht K.
Published: July 2007

Die Phasendifferenz ϕ+− zwischen den Amplituden des CP‐verletzenden Zerfalls KL → π+π− und des CP‐erhaltenden Zerfalls KS → π+π− wurde mit zwei verschiedenen Methoden gemessen. Bei beiden Methoden beobachtet man die Intensität von K0 → π+π−‐Zerfällen eines kohärenten Gemischs von KL‐ und KS‐Zuständen als Funktion der Zeit im K0‐Ruhsystem. Zur Herstellung des kohärenten Gemischs wurden entweder mit Hilfe eines Materieblocks in einem KL‐Strahl KS‐Mesonen regeneriert oder mit einem Protonenstrahl ein nahezu „reiner”︁ K0‐Zustand erzeugt, der am Target aus KL‐ und KS‐Amplituden entgegengesetzten Vorzeichens besteht.

Die beiden Meßmethoden liefern übereinstimmende Werte für ϕ+−, deren Mittelwert ϕ+− = 42,9° ± 3,2° ist. Dieses Ergebnis ist verträglich mit Modellen, die die CP‐Verletzung als Eigenschaft einer „superschwachen”︁ Wechselwirkung oder eines kleinen Anteils der schwachen Wechselwirkung betrachten. Modelle, in denen die CP‐Verletzung mit ΔI = 3/2‐Strömen in der schwachen Wechselwirkung gekoppelt ist, werden durch diese Experimente ausgeschlossen.
Soft Parametrization of Renormalized Field Theory and Kadanoff Scaling
Authors: Jegerlehner F.
Published: July 2007

The soft renormalization procedure, proposed by Gomes, Lowenstein and Zimmermann, is applied to the construction of a pre‐scaling (soft) parametrization of renormalized perturbation theory. The global pre‐scaling parameters are directly incorporated into the Lagrangian; resummation problems and subsidiary condition are completely avoided. For the A4‐theory with linear symmetry breaking and the spontaneous limit we give a detailed structural investigation in terms of partial differential equations to all orders of perturbation theory. In the second part the scaling structure and “marginal” corrections to scaling are reconsidered in terms of the soft parametrization. The pre‐scaling parametrization represents a powerful tool in dealing with the field theoretical aspects of critical phenomena.
Superfield Equations
Authors: Rühl W. , Yunn B. C.
Published: July 2007

Covariant free field equations are systematically derived for irreducible and bilinear superfields from representation theory of the Wess‐Zumino algebra. Interactions are introduced by covariance arguments alone or by the principle of local gauge invariance. Finally we construct propagators for massive superfields.
Comparison of K−p Topological Cross Sections at 32 and 33.8 GeV/c with Lower Energy Data
Authors: Kuhn D.
Published: July 2007

The K−p experiments at 32.1 GeV/c and 33.8 GeV/c in the Mirabelle bubble chamber are reviewed and the resulting topological cross sections are compared to lower energy data with beam momenta between 4.2 and 16 GeV/c. Some quantities characterizing the multiplicity distributions are compiled for these data and their energy dependence is compared to results from pp experiments. Studying the scaling behavior of the K−p multiplicity distributions, “quasi scaling” is observed for data with pLab ≧ 8.25 GeV/c.
Vacuum Energy‐Density in Quantum Electrodynamics
Authors: Manoukian Edward B.
Published: July 2007

The vacuum energy‐density in quantum electrodynamics is studied by renormalization group techniques as well as a diagrammatic analysis is carried out to investigate the dependence of on an ultraviolet cut‐off as the latter is led to become large. The study corresponds to the situation of finite electrodynamics with the renormalized fine‐structure constant α fixed in the sens of the renormalization group. In this case explicit statements about the problem at hand may be made. In passing a study of the so‐called second Legendre transform method for electrodynamics is given in an appendix.
The Causal Function in Many Body Problems
Authors: Matsumoto Hideki
Published: July 2007

Analytic properties of the causal Green's function in statistical mechanics are investigated. It is shown that the causal function can be obtained as a certain limit of an analytic function. The dual field introduced by Umezawa and Takahashi in their field‐theoretical formulation of statistical mechanics (thermo field dynamics), plays an important role to make the spectral functions real. In a few examples, it is shown explicitly that the Feynman diagram technique is applicable in the thermo‐field dynamics.
On the Systematics of the Number of Heavy Prongs in Proton‐Nucleus Interactions in Emulsion
Authors: Daftari I. K. , Bhattacharjee D. K. , Naha S. C. , Ghosh D. C. , Roy T.
Published: July 2007

The systematics of the number of heavy prongs in proton‐nucleus interactions in emulsion in the energy range from a few GeV to few hundred GeV have been studied. The results disfavour the secondary processes in the target nucleus in general and intranuclear cascading of hadrons in particular.
Exchange Currents, Isobaric Excitations and the Deuteron
Authors: Baier H.
Published: July 2007

Some recent attempts to take into account exchange currents and isobaric excitations in the electromagnetic and weak interactions of leptons with the deuteron are reviewed. After a presentation of the relevant theoretical framework the crucial experiments supporting strongly the exchange current ideas are discussed in some detail.
Quantum Electrodynamics in Solids
Authors: Matsumoto H. , Semenoff G. , Umezawa H. , Tachiki M.
Published: July 2007

A quantum field theoretical treatment of electromagnetic fields in solid is presented. The photon propagator is obtained when the current‐current correlation function is given. From the relations among matrix elements which are a consequence of the local gauge invariance of the theory, the classical Maxwell equations are derived by means of the boson transformation which is the mathematical realization of a boson condensation. The relation of the microscopic functions to the phenomenological quantities is presented.
Topological Charges in Gauge Theories
Authors: Leinaas J. M.
Published: July 2007

Topological and geometric aspects of gauge theories are examined. The geometry of the fiber‐bundle formulation of gauge theories is discussed and compared with the formalism of general relativity. The basic role played by the parallel displacement operator of this geometry is examined. With this operator a gauge independent characterization of various topological singularities and non‐singular soliton configurations is carried out.
Accelerated life‐test experiments on low‐power rectifier diodes
Authors: Windel Joachim
Published: July 2007

Low‐power rectifier diodes were stressed by different forward currents IF, reverse voltages UR, and ambient temperatures a for a time interval (0, t*) in order to analyse the resulting distributions. Owing to the limitations in the test time, t*, the gathering of comprehensive information about their performance requires high stress levels without exceeding either physical limits or the limits for initiating thermal runaway. First, the results of lifetime experiments related to the middle stress region were described by a Weibull distribution with constant shape parameter and stress‐dependent scale parameter. This model, however, did not fit sufficiently the typical features of the real‐life distribution. Therefore a non‐parametric measure called the average initial reliability in (O,t*) was defined using the experimental results. Its stress dependence was estimated. The results are guiding figures of stress conditions both for accelerated tests and for circuits with high demands on reliability.
A perspective on Shainin's approach to experimental design for quality improvement
Authors: Logothetis N.
Published: July 2007

In this article we evaluate D. Shainin's group of recommended techniques for designing and analysing experiments, viewed in relation to other methods for off‐line quality control and on‐line improvement, in particular those advocated by Taguchi and those under the banner of statistical process control.
Temperature dependence of microelectronic device failures
Authors: Pecht Michael , Lall Pradeep , Whelan Stanley J.
Published: July 2007

Recently, the use and the applicability of reliability prediction models for microelectronic devices using the temperature‐dependent Eyring and Arrhenius function, have been criticized. In fact, the temperature dependence of failure mechanisms of microelectronic devices and electronic equipment in general has been questioned. This paper discusses the effect of temperature on microelectronic failure mechanisms at various device failure sites. This paper also presents information on those mechanisms which may be more appropriately modelled by functions dependent on temperature change, the rate of temperature change and spatial temperature gradients.
Estimation of the mean cumulative number of failures in a repairable system with mixed exponential component lifetimes
Authors: Hansen Christian Kornerup , Thyregod Poul
Published: July 2007

Components in electronic systems are often observed to be likely to fail at an early age, an effect well known as the ‘infant mortality’ effect. Similarly, for systems composed of such components, a decrease in the rate of occurrence of failures, usually called the ‘reliability improvement’ effect, is seen in the early operating period. In this paper we show that such improvement may be considered as a simple consequence of the heterogeneity among the components in the population. We present a simple three‐parameter model for the distribution of the component lifetime, which has a simple physical interpretation, and from which we obtain methods for statistical inference, suitable for implementation on even small computers. The methods have been applied successfully to field failure data, collected from an industrial company.
On parameter design optimization procedures
Authors: Yum Bong‐Jin , Ko Sun‐Woo
Published: July 2007

The Taguchi idea of parameter design has received considerable attention from statisticians and engineers. However, it is only recently that some of the underlying principles of his ideas have been clarified and other alternative procedures have been proposed. This paper reviews the currently available procedures for parameter design in terms of minimizing expected loss. Advantages and disadvantages of each procedure are discussed for the three types of performance characteristics, and guidelines are provided for the choice of an appropriate procedure for a given parameter design problem.
Modern reliability assurance of integrated circuits—A strategy based on technology capability assessment and production reproducibility control
Authors: Gerling W.
Published: July 2007

Technological innovations provide integrated circuits of increased functionality and complexity, and modern design tools facilitate a new multiplicity of products, such as application‐specific products (ASICs). Traditional qualification procedures cannot keep pace with this evolution with respect to requirements of product reliability, ability of qualifying the multiplicity of future products, and market demands for saving cost and time.

A further development of a reliability assurance concept, which will be discussed here, considers design tools, basic product elements, materials, manufacturing process and controls as a ‘system’, which has to be qualified with respect to the consistency and efficiency of all of the implemented reliability assurance measures. The concept is based on the manufacturer's ‘system’ knowledge and responsibility. It is compatible with the relevant requirements of ISO 9000 and recent military standard proposals. The procedure is applied to commercial products.

The main part of this concept is the qualification of the manufacturing technology. The procedure is organized as a continuous process starting at the concept phase of a new technology and its pilot product. The various steps then follow the development, the pre‐series and series production phases. The reliability aspects concentrate on the physical properties of product elements relevant to their stability and endurance, i.e. the potential failure mechanisms and their root causes as reliability risks. Thus a major part of reliability testing for the qualification of the pilot product of a new technology can be performed without the use of the final product version. The benefits derivable from this approach are savings in time and cost as well as the capability to handle future product multiplicity.
A som study of DC‐PBH laser catastrophic failures
Authors: Montangero Paolo , Liberatore Michele , Arman Giuseppina
Published: July 2007

OBIC and PL imaging modes of a SOM have been successfully applied to the failure analysis of catastrophically degraded DC‐PBH lasers. High lateral resolution, variable in‐depth penetration and selective excitation are the most interesting features. A degradation mechanism has been found due to the development of leakage paths in the confining junctions.
The effect of barrier layers on the distribution function of interconnect electromigration failures
Authors: Pinto Mario
Published: July 2007

Electromigration data after stressing narrow lines with or without a TiW layer underneath have been analysed. The difference between the failure morphology and the failure time distributions is explained and a new statistical failure model is derived to explain the differences in electromigration observations.
Choosing the best set of quality judges: A new quality tool
Authors: Hoffman Lorrie L.
Published: July 2007

This article presents a technique which allows one to choose the ‘best’ set of quality judges. The methodology can be applied to any situation requiring discernment of a qualified inspector of products or service. The approach presented in this article selects judges who align their quality criteria with the prevailing expert. Multidimensional scaling is conducted on a disagreement matrix formed by executing multiple pairwise comparisons. An example of voice quality judging is included in the article as a practical example of the technique.
Low‐cost physical analysis techniques for the failure analysis of semiconductor components
Authors: Glacet J. Y. , Dall'oro G. Guerri
Published: July 2007

Failure analysis of semiconductor components should not only be considered as an ever increasing costly activity which is economically difficult to support, to develop, and to justify, because of the continuous technology evolution. Analytical techniques such as integrated circuit pin‐to‐pin electrical test, plastic package opening with the acid dropper, hot spot detection with liquid crystals, EBIC, voltage contrast in static and voltage coding modes, can be developed and applied in failure analysis laboratories with low‐cost equipment. Although they are not intended to replace some well‐known expensive and sophisticated analytical tools, they can provide efficient results.
Environmental testing and component reliability observations of telecommunications equipment operated in tropical climatic conditions
Authors: Sinnadurai Nihal , Kuppuswamy T. S. , Chandramouli R. , Rao B. K. N.
Published: July 2007

Safeguarding the reliability of electronics exposed to the severe conditions occurring in tropical climates, such as India, has not been adequately understood or dealt with in international specifications. Consequently, components and equipment supplied to such specifications have failed in such climates. The vulnerability of supposedly hermetic components has been suspected as a result of a full analysis of moisture ingress, and this has been borne out by comprehensive analyses of the actual failures of components supplied to international specifications, and the climatic conditions actually occurring in India. Understanding of reliability assessment and achievement has been significantly advanced by such analysis and has shown the necessity and applicability of the highly accelerated stress testing technique invented at British Telecom Laboratories more than two decades ago. Comparison has shown the significant cost benefit from the use of plastic encapsulated devices of proven reliability.
Plastic encapsulated ics in military equipment reliability prediction modelling
Authors: Brizoux M. , Deleuze G. , Digout R. , Nallino M.
Published: July 2007

This paper introduces a reliability prediction model for plastic encapsulated integrated circuits to be used in professional or defence electronics applications. The first part is a comparison between different reliability prediction models: their hypotheses, assumptions and validity domains are examined; constructive criticism is made and model amendments proposed for plastic encapsulated ICs reliability prediction. The second part presents the model itself. It addresses also thermal and environmental aspects. The third part explains how numerical values are found to fill the model and how it reflects the reliability of today's state‐of‐the‐art of plastic encapsulation. In conclusion, we present the improvements that this model can bring to reliability prediction, in the particular case of plastic packages.
Asics failure analysis using two complementary techniques: External electrical testing and internal contactless laser beam testing
Authors: Bouvet C. , Fouillat P. , Dom J. P. , Danto Y.
Published: July 2007

Functional tests with an electrical tester have revealed defects in an ASIC. Results analysis leads to incriminating different areas of the layout. A laser beam tester localizes the logic operator responsible for the dysfunction observed with the electrical tester.
GaAs MMIC reliability studies
Authors: Anderson W. T. , Roussos J. A. , Christianson K. A.
Published: July 2007

Three types of GaAs monolithic microwave integrated circuits (MMICs) were RF high temperature accelerated life tested to determine the median time before failure (MTBF). Life testing was performed under the d.c. bias conditions and RF input power levels the MMICs would be expected to use under actual operating conditions. the accelleration condition was to raise the base‐plate temperature high enough to result in degradation in approximately 1000 hours at the highest test temperature. Because the MMICs were designed for power applications, the input signal level was large enough to cause approximately 1 dB compression. Device failure was defined as a 20 per cent decrease in output power as measured at 125°C, or room temperature when the temperature control system was turned off. Under these conditions the MTBF extrapolated to a channel temperature of 125°C varied between 8 × 103 hours and 2 × 105 hours depending on the MMIC type. The primary failure mode appeared to be surface leakage currents under the passivation layer.
Component lifetime models based on weibull mixtures and competing risks
Authors: Hansen Christian Kornerup , Thyregod Poul
Published: July 2007

This paper gives a review of the statistical modelling of lifetimes of electronic components. The models considered are all based on Weibull (and exponential) distributions combined as either finite mixtures, competing risks or both. A convenient notation is introduced for this general class of models, which includes the traditional monotone hazard rate models, the bathtub model, as well as the more sophisticated roller coaster models. The main advantage of this concept is that a model may be determined by relatively few parameters, and that furthermore each parameter may have a physical interpretation in terms of initial flaws or defects as well as long‐term wear out or deterioration. The properties of the distributions are investigated in examples with different scale and shape parameters, and for different types of combinations. Also, the models are compared with another class of models based on combinations of exponential distributions, known as the phase‐type models. Finally a brief discussion of model selection and estimation methods is included.
An extended mathematical model for failure kinetics
Authors: Drapella Antoni
Published: July 2007

In practice we often observe some kind of ‘self‐acceleration’ when degradation causes the local temperature to increase, and in turn the temperature accelerates degradation. In this paper an extended model for failure kinetics is proposed to describe the phenomenon mentioned above. It is a common belief that a non‐linear relation between logarithmic lifetime and inverse temperature reveals a change of failure mechanisms. The results of the paper tell us that non‐linearity may be produced by a single failure process with more complex failure kinetics than the simple reaction of the first order.
Software reliability model selection
Authors: Khoshgoftaar Taghi M. , Woodcock Timothy G.
Published: July 2007

No one software reliability growth model has ever been shown to work well in all circumstances. This paper presents our evaluation results for two case studies in which the Akaike information criterion (AIC) was used. The AIC not only selects the best model among several reliability models, but also possess favourable properties that practitioners like to see in their software reliability modelling practices. These properties include simplicity, accuracy and ease of application. We propose using the Akaike information criterion to select the best model for each software system.
On the measurement of field return rates
Authors: Shen Michael S.
Published: July 2007

A set of well‐defined equations is required for quantifying statistical product quality and reliability. Specific equations and their inherent measurement errors as a function of reporting period, lead time and fluctuating shipment levels are discussed. This paper covers three quality and reliability measurements, two being new‐shipment measurements: (1) overall embedded annualized field return rate, (2) short‐term or four‐quarter rolling annualized field return rate, and one being repair quality: Rate of re‐return.
A comparative reliability assessment of 750nm, 1060nm and 1300nm high power surface light emitting diodes
Authors: Lindsay C. E.
Published: July 2007

A comparative study of the reliability of high power double heterojunction surface light emitting diodes (SLEDs) operating at 750nm, 1060nm and 1300nm is reported. Data analysis from 9500 hours of fully automated life testing concludes that extremely reliable devices can be produced. Degradation and failure characteristics specific to each operating wavelength are described and related to structural and performance data on each device batch. Median life and activation energies are calculated.