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We study whether the integrity of local governments has effects on municipal bond coupon rate. We conjecture that higher integrity is associated with lower bond coupon rate. One of proxies for the integrity is the integrity index which Anti-Corruption and Civil Rights Commission of Korea announces annually. The high degree of the index implies high integrity. We also use the number of crimes by local government officials as the integrity measure. Empirical results show that Increasing a unit of integrity is equivalent to decreasing 0.34% of municipal coupon bond. The sensitivity of the integrity to municipal bond coupon rate is stronger before 2007-2008 financial crisis, when the coupon rate was higher, than after the crisis. Overall, our results imply that local governments could save financing cost by improving the integrity of the governments.

The purpose of this paper was to attempt to confirm the root cause of unstable stitch pull strength in PQFN package and propose some permanent solutions for it.

A screen experiment was designed to find the key process out of the manufacturing flow; a non‐destructive detaching method and cross section polishing were used to inspect the bond integrity; Auger analysis assisted with argon ion sputter was tried to confirm the contamination; finally the manufacturing processes were redesigned to prevent the contamination.

Some first aids of process optimization got little improvement; the screen experiment of processes found solder die bonding was the one resulted into a poor bond integrity which was demonstrated by non‐destructive detaching method and cross section inspection; Auger analysis assisted with argon ion sputter detected that there was a tin layer thicker than 20 nm coated on the bonding surface and the wire bondability of gold wire on this tin coating was poor; the lead frame was redesigned to prevent the wetting and flowing of tin and got a perfect performance.

Because of the limitation of time and resources, the proposed solutions for this issue could be studied more deeply.

This paper set up an example how to find out the root cause from the complex manufacturing process flow and put forward a quick solution accordingly for the issue.

The effect of ultrasonic agitation on hybrid devices during PCB cleaning has long been suspected as leading to device malfunction. However, little or no data exist to substantiate or quantify these effects. This paper describes a limited study into these effects using both test vehicles and commercial products, and discusses their variation with exposure time, the types and mechanisms of failure, and the rle of the hybrid package construction. It is demonstrated that the design of the hybrid package is critical in determining its susceptibility to ultrasonic damage.

This study aims to enhance the precision and efficiency of English Bond brick masonry by developing three unified templates: Tc, T1, and T2. These templates are designed to address the complexities in the placement of bricks, particularly queen closers and brickbats, in English Bond patterns.

The research introduces a unique numbering system integrated within each template to facilitate accurate brick placement. Template Tc is designed explicitly for corner masonry, while T1 and T2 are developed for linear masonry along the X and Y directions, respectively. The approach standardizes the bricklaying process, ensuring proper alignment and bricks overlap.

Applying these templates significantly improves the efficiency and pace of English bond brick masonry. They simplify the construction process, reduce errors, and enhance the overall quality of masonry work. The study demonstrates that using these templates results in consistent and high-quality brickwork, surpassing traditional speed, efficiency, and accuracy methods.

This study contributes a novel, systematic approach to bricklaying in English Bond masonry. The introduction of unified templates aids in skill acquisition for professionals and learners, ensuring flawless execution of masonry projects. This innovative approach holds great value in modern construction practices, promoting standardization and excellence in masonry work.

An overview has been presented on the topic of alternative surface finishes for package I/Os and circuit board features. Aspects of processability and solder joint reliability were described for the following coatings: baseline hot‐dipped, plated, and plated‐and‐fused 100Sn and Sn‐Pb coatings; Ni/Au; Pd, Ni/Pd, and Ni/Pd/Au finishes; and the recently marketed immersion Ag coatings. The Ni/Au coatings appear to provide the all‐around best options in terms of solderability protection and wire bondability. Nickel/Pd finishes offer a slightly reduced level of performance in these areas which is most likely due to variable Pd surface conditions. It is necessary to minimize dissolved Au or Pd contents in the solder material to prevent solder joint embrittlement. Ancillary aspects that include thickness measurement techniques; the importance of finish compatibility with conformal coatings and conductive adhesives; and the need for alternative finishes for the processing of non‐Pb bearing solders are discussed.

Drawing on transaction cost economics (TCE) and social exchange theory (SET), the purpose of this paper is to explain why and how external environment, governance structures and interpersonal relationships influence information and communication technology (ICT)-enabled information sharing in supply chains (SCs) of small- and medium-sized enterprises (SMEs) from developing economies.

The authors adopt a theory-building approach using a multiple case study design, including four SMEs operating in SCs from two developing economies (i.e. Republic of North Macedonia and People’s Republic of China), in which the authors conduct both within-case and cross-case analyses.

Social bonds (known as vrski in Macedonian and guanxi in Chinese) were found to govern buyer–supplier exchanges by supporting the establishment of personal trust and the reduction of distrust. These social bonds compensate for the institutional deficiencies in developing economies and thus encourage ICT-enabled information sharing by SMEs in their SCs.

By applying the theoretical perspectives of TCE and SET to the cross-case analysis, the authors develop nine propositions to explain ICT-enabled information sharing and its interdependencies with external environment, governance structures and interpersonal relationships in developing economies. Further research is recommended to refine and test the generalizability of the theoretical model.

Firms have to develop and nurture social bonds with their suppliers from developing economies to reduce risks related to the environmental uncertainty and institutional voids. This can increase trust and decrease distrust associated with ICT-enabled information sharing.

The study examines why and how external environment (environmental uncertainty and institutional environment), social bonds (vrski and guanxi) and interpersonal mechanisms (trust and distrust) influence ICT-enabled information sharing of SMEs operating in developing economies.

Tape ball grid array (TBGA) packages offer many of the advantages of plastic BGAs, namely excellent durability, improved board space utilisation and ease of surface mount assembly along with the associated yield improvements. TBGA packages go a step further, however, and offer the added benefits of improved signal integrity, better heat dissipation, and extendability to higher pin counts. This paper outlines the design and material selection process to produce a low‐cost TBGA which allows the wire bonding of a die. This type of package offers an attractive solution for applications requiring mid to high I/O capability and good electrical and thermal properties. Preliminary results have demonstrated the feasibility of wire bonding to this package at temperatures up to 200°C.

The challenge presented by advanced package development in the past five years has further accentuated the constant need for package quality and reliability monitoring through extensive laboratory testing and evaluation. As pin counts and chip geometries have continued to increase, there has been additional pressure from the military and commercial sectors to improve interconnect designs for packaged chips, including chips directly attached to the printed wiring board (PWB). One of the options employed has been tape automated bonding (TAB). However, this assembly technique also presents new standardisation, qualification and reliability problems. Therefore, at Rome Air Development Center (RADC), there is regular assessment (through in‐house failure analysis studies) of parts destined for military and space systems. In addition, Department of Defense (DoD) high tech development programmes, such as very high speed integrated circuits (VHSIC), have utilised all present screening methods for package evaluation, and have addressed the need for development of more definitive non‐destructive tests. To answer this need, two RADC contractual efforts were awarded on laser thermal and ultrasonic inspection techniques. Through these package evaluations, a number of potential reliability problems are identified and the results provided to the specific contractors for corrective action implementation. Typical problems uncovered are lid material and pin corrosion, damage to external components and adhesion problems between copper leads and polyimide supports, hermeticity failures, high moisture content in sealed packages and particle impact noise detection (PIND) test failures (internal particles). Further tests uncover bond strength failures, bond placement irregularities, voids in die attach material (potential heat dissipation problems), and die surface defects such as scratches and cracks. This presentation will review the specific package level physical test methods that are employed as a means of evaluating reliable package performance. Many of the tests, especially the environmental tests—e.g., salt atmosphere and moisture resistance—provide accelerated forms of anticipated conditions and are therefore applied as destructive tests to assess package quality and reliability in field use. In addition to a manufacturer's compliance with designated qualification procedures, the key to package quality lies in utilising good materials and well‐controlled assembly techniques. This practice, along with effective package screen tests, will ensure reliable operation of very large scale integration (VLSI) devices in severe military and commercial environment applications.

The purpose of this paper is to better understand how interorganizational relationships influence information and communications technology (ICT)-enabled supply chain (SC) interactions of small- and medium-sized enterprises (SMEs) in developed versus developing economies through the theoretical lens of transaction cost economics and social exchange theory.

The paper uses case study data to examine SMEs operating in both a developing economy, the Republic of Macedonia, and a developed economy, the USA.

Insights reveal that the institutional context (i.e. environmental uncertainty) has significant indirect influence on ICT use by SMEs from rule-based and relationship-based SCs in the wine industry through contractual and relational mechanisms (i.e. contracts and social bonds).

This study contributes to the body of SC knowledge by providing a comparative qualitative analysis of interorganizational factors (i.e. information sharing, collaboration, trust, contractual governance, relational governance and environmental uncertainty) that influence ICT use by SMEs in upstream wine SCs from developing and developed economies.

This paper provides valuable implications for the SC participants (e.g. grape suppliers, wineries and other suppliers) and industries (e.g. Macedonian and American wine industries) related to ICT use and non-use.

This study makes a novel contribution by being the first to qualitatively explore ICT use by SMEs from the wine industry and to identify the importance of legal institutional environment in buyer–supplier exchanges from developed versus developing economies.

To provide a basis for making assessment of the safety of adhesively bonded joints after they have been de‐painted by a dry abrasive method or a wet chemical method.

Stress analysis by a finite element method has been conducted for metal/composite and composite/composite joints in a single lap configuration. The effects of degradation of composite and adhesive, separately or combined, on the stresses in the adhesive layer bonding the two components are studied. Effects of wet and dry conditions of de‐painting are included in the study. It is assumed that in the composite these conditions affect only the laminae close to the surface from which the paint coating is removed.

The locations and values of the maximum peel and shear stresses in the adhesive are determined for both joints under different assumed conditions of degradation caused by de‐painting.

Experimental data indicating the extent of surface damage caused by de‐painting is not available.

Extensive literature study did not show any investigation of composite surface damage and adhesive property degradation on integrity of adhesively bonded joints. Results reported here will be of use in assessing effects of de‐painting on the structural performance of adhesively bonded joints.