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The initial excitement over increased solder joint densities, higher manufacturing throughput, and superior electrical performance brought forth by surface mount technology (SMT) has been replaced by frustrations over lower yields and the inherent difficulties of inspecting hidden solder joints. In the plated through hole (PTH) process, rework and inspection tasks were not only relatively easier tasks, but also less costly. The high cost of inspecting and reworking SMT assemblies dictates a rethinking of the assembly process. Increasing first time yields becomes the key to reducing SMT inspection and rework costs. In a high volume facility, a 100% visual inspection process is not feasible because of the high cost of inspection and rework. However, if a company intends to remain competitive, inspection and rework must be reduced without a sacrifice to final product quality. Realising that it is not possible to ‘inspect’ quality into a product, improved yield must result from a controlled process environment. By maintaining a controlled environment, one will be provided with lower inspection costs, lower rework costs, lower scrap and, in the final analysis, improved product quality. At the heart of any process control environment should be a real‐time process control system designed specifically to accommodate SMT process defects. Process monitoring is accomplished by locating and identifying SMT process flaws. These flaws will then be reported to a host system for statistical analysis. These are statistical data used to make timely adjustments to the various stages of the assembly process in a real‐time manner. Being able to monitor the production process objectively in real time, and detect hidden flaws accurately, are the keys to having a successful process inspection system. Automated X‐ray Inspection is gaining acceptance as a viable process monitoring tool, capable of detecting and reporting SMT process flaws, including those hidden flaws not reported with typical visual inspection systems. The purpose of this paper is to show how an Automated X‐ray Inspection system can be integrated into the SMT production process as a cost‐effective method for improving SMT yield.

The role of leadership through senior management teams (SMT) has received increasing attention over the past several decades. Such leadership requires principals to play a key role in promoting SMT effectiveness. Therefore, according to the input–mediator–outcome model (Ilgen et al., 2005), this study's purpose is to investigate the mediating role of school SMT learning in the relationship between principal systems thinking (PST) and SMT effectiveness after accounting for students' socioeconomic backgrounds and SMT members' tenure.

A three-source survey design with self-reported and non-self-reported data was used, from a sample of 282 participants from 71 elementary schools in Israel. The sample included principals and SMTs. Data were aggregated at the school level of analysis.

The results from structural equation modeling and bootstrapping analysis indicated that SMT learning fully mediates the relationship between PST and SMT effectiveness, irrespective of the students' socioeconomic backgrounds.

This study provides important insights into the role of SMT learning as a mediator in the relationship between PST and SMT effectiveness. In addition, the study responds to the call of previous studies to examine the effects of PST on characteristics and outcomes at the group level. Moreover, the proposed integrative model highlights the importance of SMT learning and suggests new ways to encourage it.

Surface mount technology (SMT) is widely used and plays an important role in electronic equipment. The purpose of this paper is to reveal the effects of interface cracks on the fatigue life of SMT solder joint under service load and to provide some valuable reference information for improving service reliability of SMT packages.

A 3D geometric model of SMT package is established. The mechanical properties of SMT solder joint under thermal cycling load and random vibration load were solved by 3D finite element analysis. The fatigue life of SMT solder joint under different loads can be calculated by using the modified Coffin–Manson model and high-cycle fatigue model.

The results revealed that cracks at different locations and propagation directions have different effect on the fatigue life of the SMT solder joint. From the location of the cracks, Crack 1 has the most significant impact on the thermal fatigue life of the solder joint. Under the same thermal cycling conditions, its life has decreased by 46.98%, followed by Crack 2, Crack 4 and Crack 3. On the other hand, under the same random vibration load, Crack 4 has the most significant impact on the solder joint fatigue life, reducing its life by 81.39%, followed by Crack 1, Crack 3 and Crack 2. From the crack propagation direction, with the increase of crack depth, the thermal fatigue life of the SMT solder joint decreases sharply at first and then continues to decline almost linearly. The random vibration fatigue life of the solder joint decreases continuously with the increase of crack depth. From the crack depth of 0.01 mm to 0.05 mm, the random vibration fatigue life decreases by 86.75%. When the crack width increases, the thermal and random vibration fatigue life of the solder joint decreases almost linearly.

This paper investigates the effects of interface cracks on the fatigue life and provides useful information on the reliability of SMT packages.

There has been an increasing trend toward the creation of senior management teams (SMTs) which are characterized by a high degree of functional heterogeneity. Although such teams may create better linkages to information, along with the benefits of functional heterogeneity comes the potential for conflicts that stem from the value differences among subcultures in an organization. These conflicts can adversely affect performance. The purpose of this paper is to examine how school leaders’ activities mediate the relationship of SMT functional heterogeneity to SMT effectiveness (in-role performance and innovation).

Data, which were obtained through a survey, was collected from a sample of 92 schools in Israel. Data were collected from two sources (principals and SMT members) to minimize problems associated with same source and common method bias. Data were aggregated at the team level of analysis.

The results of structural equation model indicated that principal’s internal activities enhanced SMT in-role performance whereas principals’ external activities enhanced SMT innovation. The results also showed that principal’s internal activities are full mediators of the relationship between functional heterogeneity and SMT in-role performance.

This study has implications for policies involving the design and implementation of leadership tools to effectively manage SMTs. The results of this study can help principals to establish priorities and allocate their time and resources more effectively, both inward and outward the SMT boundary so as to assist functionally heterogeneous SMTs translating the benefits of functional heterogeneity into significant achievements.

The purpose of this study is that the effects of surface mount technology (SMT) assembly process on the product lifetime of fine-pitch printed circuit boards (PCBs) were investigated under biased highly accelerated stress testing (HAST).

SMT assembly from a semiconductor SMT assembly process was replicated to test PCBs under the same conditions as SMT-assembled PCBs. The median lives µ and standard deviation s of the test PCBs were calculated from the log-normal distribution. The failure analysis of current leakages was conducted by the focused ion beam, scanning electron microscopy and energy-dispersive X-ray spectroscopy. Using the inverse power law and modified Peck-H’s relationship, the PCB lives at accelerated (by SMT assembly stress) and user conditions were calculated.

The failure analysis demonstrated that SiO₂ and BaSO₄ fillers added for stiffening organic materials promote current leakage failure. Therefore, the hydrophobicity of these fillers is believed to be necessary to suppress the current leakage failure under biased HAST. The inverse power law model indicates that the acceleration life model with SMT assembly stress can be given as follows: L(V) = 271.9(S)^−0.5031. From modified Peck-H’s relationship, after the third SMT assembly, the time required to attain 0.96 per cent failures at 35°C/60 per cent RH/1.9 V and 130°C/85 per cent RH/3.5 V are 129 y and 69.5 h, respectively. The biased HAST at 130°C/85 per cent/3.5 V after the third SMT assembly for 69.5 h on 238 samples could be recommended as an early quality-monitoring procedure.

In the future, the failure modes in an early stage of a bathtub should be analyzed and the life prediction model should be studied accordingly.

Through this study, the lifetime prediction model and early quality-monitoring procedure for organic substrates because of SMT assembly stress were obtained.

This two-part study aims to contribute to the body of knowledge on team development by examining the development of self-managing teams (SMTs) in healthcare. Based on an exploration of the team development literature, a perspective on SMT development was created, which suggested that SMTs develop along a non-sequential pattern of three processes–team management, task management and boundary management and improvement–that is largely the result of individual, team, organizational and environmental-level factors.

The perspective on SMT development was assessed in a Dutch mental healthcare organization by conducting 13 observations of primary mental healthcare SMTs as well as 14 retrospective interviews with the self-management process facilitator and advisors of all 100 primary mental healthcare SMTs.

Empirical results supported the perspective on SMT development. SMTs were found to develop along each of the three defined processes in a variety or possible patterns or simultaneously over time, depending on many of the identified factors and three others. These factors included individual human capital, team member attitudes and perceived workload at the individual level, psychological safety, team turnover, team size, nature of the task and bureaucratic history at the team level, and management style and material and social support at the organizational level.

This study provides a non-sequential model of SMT development in healthcare, which healthcare providers could use to understand and foster SMTs development. To foster SMT development, it is suggested that cultural change need to be secured alongside with structural change.

Even though various team development models have been described in the literature, this study is the first to indicate how SMTs in the healthcare context develop toward effective functioning.

Reorganizing schools and managing through teams is seen as a way to achieve school goals, especially in educational contexts that are highly focused on measurable student achievements. This shift to shared leadership requires principals to play a key role in promoting school management team (SMT) outcomes. Accordingly, this study aims to investigate how principals' personality traits and behavior complement each other and combine in an integrative model of SMT effectiveness. Specifically, the research aims to examine the mediating role of principals' internal and external boundary activities between principals' traits from the Big Five typology, namely, extraversion, conscientiousness, agreeableness, openness to experience and neuroticism and SMT effectiveness.

Data were collected from two sources to minimize problems associated with same-source bias. In total, 92 SMTs and their principals from 92 public schools in Israel participated in the study. Overall, 295 SMT members and 92 principals were included in the sample. Data were aggregated at the school level of analysis. The theoretical model was tested with structural equation modeling. The bootstrapping procedure, to ascertain the presence of indirect effects, was employed.

The findings of structural equation modeling indicated that principal external activities partially mediated the relationship of conscientiousness and extraversion to SMT effectiveness, providing support for an integrated trait–behavioral model of leadership for SMT effectiveness.

As schools involve increasingly interconnected professional networks based on relationships, acknowledging that SMT effectiveness may be influenced by principals' personality traits that translate into leadership behavior may clarify the implications of principals' traits for educational teams. Importantly, the proposed integrative model points to possible mechanisms linking principal traits, behaviors and effectiveness by positioning principals' boundary activities as one possible mechanism through which principal traits facilitate SMT effectiveness. The findings can help deepen our understanding of which kinds of principals engage in boundary activities, contributing to the discussion of what factors influence principals' practices with implications for school managers' selection practices.

Evaluates the mechanical properties of 60 different shirting materials: fabric extensibility, formability, shear rigidity, bending rigidity, relaxation shrinkage, and hygral expansion by the adoption of the fabric assurance by simple testing (FAST) system. Investigates manufacturing processes comprising spreading, cutting, sewing, handling, pressing and packaging and correlates the measured properties of the shirting fabric with their actual performance during making up. Claims this overall evaluation of respective fabric performance enables manufacturers to identify the range of mechanical properties ideal for high‐quality shirt production. Adds that specific manufacturing instructions can be prepared, based on the results of fabric property evaluation, for fabrics which tend to present difficulties in production. Points out that these can considerably expedite the manufacture of garments, avoiding the alternative – expensive “trial and error” – solution to problems.

The purpose of this paper is to examine the impact of the constructs – utilitarian, hedonic and social value on the perceptions of the full-time instructors related to their social media technology (SMT) management for learning and teaching practices at workplace.

A survey is used to gather the data from 180 instructors (full time) working at one of the colleges owned by the ministry of manpower, Oman. This paper uses reliability analysis to determine Cronbach’s α and analysis of variance for the empirical investigation of instructors’ perceptions on SMT management.

The analysis shows that 98 per cent of the instructors use SMTs at their workplace. Social influence is found more dominating than utilitarian and hedonic constructs in impacting on instructors’ intention for SMT use. Findings also claim that higher the use of SMT at workplace stronger the influence on learning and teaching practices of higher education instructors.

The findings of this study can be used as the recommendations for all the faculty members to use SMTs for their educational, learning and teaching practices. The administration can develop policies to motivate instructors to manage such technologies for professional and personal development to enhance learning and teaching environment at workplace.

This study is perhaps the leading attempt to use utilitarian, hedonic and social value perceptions of the instructors to investigate the management of SMTs in an academic culture and settings of the developing country in the Middle East (Oman).

This study seeks to examine gender differences amongst science, mathematics and technology (SMT) teachers with regards to nine school environment variables as well as the association of these variables with teachers' professional background and school characteristics.

A questionnaire was used to collect data from a sample of 275 female and 260 male SMT teachers.

A multiple analysis of variance revealed a statistically significant gender difference on the combined nine school environment variables. Analysis of variance further revealed a significant gender difference in work pressure, principal leadership, teacher‐student relationship and staff freedom. Gender differences in SMT teachers' perceptions of work pressure and principal leadership persisted after controlling for teachers' background and school characteristics. It is recommended that, principals of secondary schools be encouraged to be more democratic and flexible so as to foster an atmosphere of good working relationships with their teachers.

The study encourages SMT teachers to improve on their perception of students' learning in SMT. The impact of a teacher's interest or bias on students' can have a far reaching outcome on their learning.