bluuebunny/crossref_metadata_2025 huggingface dataset:
Food quality score and anthropometric status among 6‐year‐old children: A cross‐sectional study
Authors: Askari Mohammadreza , Daneshzad Elnaz , Bellissimo Nick , Suitor Katherine , Dorosty‐motlagh Ahmad Reza , Azadbakht Leila
Published: February 2021

Objective

Weight status and growth during childhood are indicative of healthy development throughout the lifespan. It is well understood that dietary patterns and overall quality of diet can prevent disease, improve health status and optimise growth and development. The current study investigates the relationship between overall diet quality and measures of childhood development including body mass index and height‐for‐age in 6‐year‐old children.

Methods

This cross‐sectional study was conducted across 788 6‐year‐old children from Tehran, Iran, in 2018. Food quality score (FQS) was used to assess overall diet quality, in addition to a modified food‐based diet quality score specific to children (modified FQS) developed by our group.

Results

Participants in the highest tertile using the modified FQS had the highest height‐for‐age z‐score (HAZ) (−0.509 ± 0.028 vs −0.605 ± 0.028; P = .048). In contrast, participants in the highest tertile assessed using the original FQS had a higher BMI for age z‐score (BAZ) compared to participants in the first tertile (0.391 ± 0.072 vs 0.266 ± 0.072; P = .023). Children within the highest tertile, according to the original FQS, compared to those within the lowest tertile were 49% less likely to be categorised as severely underweight (OR: 0.51; 95% CI: 0.47‐0.98).

Conclusions

Findings presented in this study demonstrate that FQS was significantly associated with participants characterised as severely underweight; however, FQS was not associated with other anthropometric parameters. Therefore, future well‐designed cohort studies are required to address limitations of the current study.
Regional and facility disparities in androgen deprivation therapy for prostate cancer from a multi‐institutional Japan‐wide database
Authors: Shiota Masaki , Sumikawa Ryota , Onozawa Mizuki , Hinotsu Shiro , Kitagawa Yasuhide , Sakamoto Shinichi , Kawai Taketo , Eto Masatoshi , Kume Haruki , Akaza Hideyuki ,   the Japan Study Group of Prostate Cancer (J‐CaP)
Published: February 2021

Objectives

To examine the differences in prognosis of prostate cancer patients receiving primary androgen deprivation therapy by region and facility type using a Japan‐wide database.

Methods

Data on patients treated with primary androgen deprivation therapy between 2001 and 2003 from a nationwide community‐based database established by the Japan Study Group of Prostate Cancer were obtained. Clinicopathological characteristics and prognostic variables, including progression, cancer‐specific survival and overall survival, were compared according to region and facility type where the patients were treated.

Results

Among 19 162 patients, 7102 (37.1%) and 12 060 (62.9%) men were in urban and rural areas, respectively, and 3556 (18.6%), 13 623 (71.1%) and 1983 (10.3%) patients were enrolled from academic centers, non‐academic hospitals and urological clinics, respectively. The risks of progression, cancer‐specific mortality and all‐cause mortality were comparable between urban and rural areas in propensity‐score matched analysis. Risks of progression, cancer‐specific mortality and all‐cause mortality in urological clinics were higher than those in academic centers in propensity‐score matched analysis.

Conclusions

Our findings suggest that Japan facility type, but not geographical regions, might affect the prognosis of prostate cancer patients receiving primary androgen deprivation therapy.
What does genetic research tell us about the origins of language and literacy development? A reflection on Verhoef et al. (2020)
Authors: Chow Bonnie Wing‐Yin , Wong Simpson W.L.
Published: February 2021

Quantitative genetic research has set the stage for the exploration of genetic influences and the underlying mechanisms that undergird language and literacy development. Following this line of enquiry, Verhoef et al. (2020) address a critical issue related to genetic processes by comparing whether the genetic mechanism known as innovation or amplification plays a more pivotal role in literacy development during the period of early childhood to early adolescence, using the cutting‐edge technique called the genome‐wide complex trait analysis. This commentary reviews and discusses the implications of the provocative findings that stem from their study and offers concrete directions for future research. Embedded in our reflections are discussions related to the generalist genes vs genetic specificity debate, language universality vs specificity, as well as the role of environment in genetic influences. Taken together, the discussions in the commentary have highlighted the need for more in‐depth explorations of the interplay between genes and literacy development through a multi‐disciplinary approach.
Parenting as a Communication Process: Integrating Interpersonal Communication Theory and Parenting Styles Conceptualization
Authors: Estlein Roi
Published: February 2021

The goal of this article is to theoretically extend the perspective on the conceptualization of parenting styles (Baumrind, 1971; Maccoby & Martin, 1983) to, first, employ a reciprocal perspective on parent–child relationship dynamics and, second, explore potential antecedents of parenting styles. After presenting the parenting styles typology and the associations between parenting styles and child outcomes, I use constructivism and relational framing theory to illustrate how interpersonal communication theoretical perspectives can contribute to the parenting styles literature. Finally, I call for further integration of interpersonal communication theories and parenting styles.
Assessment of enthesopathy in patients with acne vulgaris: A case‐controlled trial
Authors: Abdellatif Azmy A. , Hasan Mohamed S. , Fahmy Ahmed M. , Mahmoud Osama E. , Elsaie Mohamed L.
Published: February 2021

Aim

This case‐controlled study aimed at evaluating whether enthesitis is possibly associated with acne vulgaris.

Methods

This study was carried out on 90 patients with acne vulgaris and 30 normal individuals who were subjected to full history talking, acne scoring system, general, dermatological, musculoskeletal examination, and musculoskeletal ultrasonography with Doppler flow.

Results

A significant relation (P < 0.05) was discovered between left femoral condyle tenderness, which increased left femoral condyle hypoechogenicity on ultrasound. Moreover, a highly significant relation (P < 0.001) was established between tenderness on clinical examination and hypoechogenicity on ultrasound at three sites (right humerus epicondyle, right femoral condyle, and left humerus epicondyle). An association between tenderness and ultrasound increased thickness was significantly reported in the left femoral condyle (P < 0.05). Hypoechogenicity on ultrasound examination was more statistically evident with increased acne severity at the left Achilles tendon (LA), while enthesis calcifications (enthesophytes) were significantly associated with increased acne severity in the left humerus epicondyle (LA) and the right Achilles tendon (RA) (P < 0.05).

Conclusion

There is a solid possibility acne is a systemic disease triggering other co‐morbidities beyond skin which needs to be fully elucidated by further research evidence.
Influence of family history, body mass index, selected dietary factors, personal habits, and menstrual history on oily skin in young women
Authors: Yang Zhusheng , Yang Xiumin , Chen Xue , Wang Ying
Published: February 2021

Background

Sebum secretion is affected by many internal and external factors.

Objective

To identify risk factors in terms of family history, body mass index, selected dietary factors, personal habits, and menstrual history that may be associated with oily skin in young women.

Participants and Methods

We conducted a case‐control study of young women aged 18–35 who came to Beijing Tongren Hospital for attending a health checkup. Cases were subjects with subjective skin type as oily skin. Control subjects were people with normal or dry skin. A standardized questionnaire on subjective skin type, family history of oily skin in first‐degree relatives, menstrual history, personal habits, and selected dietary factors was administered to 540 subjects. Univariate and multivariate logistic regression analyses were performed for risk factors associated with oily skin.

Results

A family history in first‐degree relatives and a body mass index of more than 24 kg/m2 were risk factors that increases likelihood of oily skin in young women (odds ratio 3.281, 95% confidence interval 2.204–4.882; odds ratio 1.677, 95% confidence interval 1.081–2.600, respectively). For those who consumed more than three servings of milk or sweets per week, the risk increased with the diet (odds ratio 1.634, 95% confidence interval 1.126–2.370; odds ratio 1.970, 95% confidence interval 1.034–3.754, respectively). There was no correlation between smoking, drinking alcohol, or menstrual variables and the risk of oily skin.

Conclusions

Family history, overweight and obesity, and a diet rich in milk or sweets are risk factors that increase likelihood of oily skin in young women. These findings may provide an opportunity to better guide skin care for patients.
Health status and health service use of urban Aboriginal children attending an Aboriginal community child health service in Sydney
Authors: Harding Georgia , Hu Nan , Larter Natasha , Montgomery Alicia , Stephensen Jennifer , Callaghan Lola , Zwi Karen , Lingam Raghu , Woolfenden Sue
Published: February 2021

Aim

There is limited information on the health status of urban Australian Aboriginal children and young people attending community‐based child health services. Such information is vital to plan appropriate services. The objective of the study is to describe the health status and service use of children and young people presenting to an urban Aboriginal Community Paediatric Service in Sydney, Australia.

Methods

Cross‐sectional analysis of routinely collected data extracted from electronic medical records and the Australian Immunisation Register for urban Aboriginal children and young people aged 0–18 years who visited the service between January 2013 and December 2017.

Results

A total of 273 Aboriginal children and young people had 609 occasions of service. Almost all (97.35%) were fully immunised. Forty‐six percent of occasions of service noted >3 diagnoses; 55% of the consultations were for mental health and behavioural disorders. The most frequent diagnoses were speech and language delay, attention deficit hyperactivity disorder and school difficulty. Psychosocial concerns were noted in 61.2% of occasions of service, and 19.4% of children had a history of prematurity. Eighty‐five percent of consultations had an onward referral to additional services. The most common referrals were for audiology, ear‐nose and throat specialists and speech therapy. There were low numbers of referrals to mental health services relative to the high number of mental health diagnoses.

Conclusion

It is essential that we address the mental, developmental and psychosocial needs of Aboriginal children and young people who attend urban Community Child Health services. Integrated service models should be developed in partnership with Aboriginal community to do this.
OsTPP1 regulates seed germination through the crosstalk with abscisic acid in rice
Authors: Wang Guanqun , Li Xiaozheng , Ye Nenghui , Huang Mingkun , Feng Lei , Li Haoxuan , Zhang Jianhua
Published: February 2021

Seed germination is essential for direct seeding in rice. It has been demonstrated that trehalose‐6‐phosphate phosphatase 1 (OsTPP1) plays roles in improving yield and stress tolerance in rice.

In this study, the roles of OsTPP1 on seed germination in rice were investigated. The tpp1 mutant germinated slower than the wild‐type (WT), which can be restored by exogenous trehalose. tpp1 seeds showed higher ABA content compared with WT seeds. The tpp1 mutant was hypersensitive to ABA and ABA catabolism inhibitor (Dinicozanole). Furthermore, two ABA catabolism genes were downregulated in the tpp1 mutant which were responsible for increased ABA concentrations, and exogenous trehalose increased transcripts of ABA catabolism genes, suggesting that OsTPP1 and ABA catabolism genes acted in the same signaling pathway.

Further analysis showed that a transcription factor of OsGAMYB was an activator of OsTPP1, and expression of OsGAMYB was decreased by both the exogenous and endogenous ABA, subsequently reducing the expression of OsTPP1, which suggested a new signaling pathway required for seed germination in rice. In addition, ABA‐responsive genes, especially OsABI5, were invoved in OsTPP1‐mediated seed germination.

Overall, our study provided new pathways in seed germination that OsTPP1 controlled seed germination through crosstalk with the ABA catabolism pathway.
Study to evaluate the optimal dose of remifentanil required to ensure apnea during magnetic resonance imaging of the heart under general anesthesia
Authors: Arnold Philip , Sanaulla Syed , Hampson Lisa V. , Davis Annette , Tan Jacinth , Cowen Ruth , Kaleem Musa , Williams Alexandra , Wadsworth Ian , Jaki Thomas
Published: February 2021

Background

Magnetic resonance (MRI) scanning of the heart is an established part of the investigation of cardiovascular conditions in children. In young children, sedation is likely to be needed, and multiple controlled periods of apnea are often required to allow image acquisition. Suppression of spontaneous ventilation is possible with remifentanil; however, the dose required is uncertain.

Aims

To establish the dose of remifentanil, by infusion, required to suppress ventilation sufficiently to allow a 30‐s apnea during MRI imaging of the heart.

Method

Patients aged 1–6 years were exposed to different doses of remifentanil, and the success in achieving a 30‐s apnea was recorded. A dose recommendation was made for each patient, informed by responses of previous patients using an adaptive Bayesian dose‐escalation design. Other aspects of anesthesia were standardized. A final estimate of the dose needed to achieve a successful outcome in 80% of patients (ED80) was made using logistic regression.

Results

38 patients were recruited, and apnea achieved in 31 patients. The estimate of the ED80 was 0.184 µg/kg/min (95% CI 0.178–0.190). Post hoc analysis revealed that higher doses were required in younger patients.

Conclusion

The ED80 for this indication was 0.184 µg/kg/min (95% CI 0.178–0.190). This is different from optimal dosing identified for other indications and dosing of remifentanil should be specific to the clinical context in which it is used.
Impacts of trauma‐ and violence‐informed care education: A mixed method follow‐up evaluation with health & social service professionals
Authors: Wathen C. Nadine , MacGregor Jennifer C. D. , Beyrem Sandy
Published: February 2021

Objectives

Trauma‐ and violence‐informed care (TVIC) creates safety by understanding the impacts of trauma on health and behavior, and the intersecting impacts of structural and interpersonal violence. This study examined the impact, 1–2 years later, of TVIC professional education.

Design, Sample and Measurements

We conducted a mixed method descriptive follow‐up evaluation (online survey, n = 67, and semi‐structured interviews, n = 7) with health and social service providers, leaders and researchers who attended TVIC workshops. Participants were asked how the workshop impacted their thinking, actions and perceptions of organizational changes.

Results

Participants reported greater impact on attitudes than on behaviors. The most common change in awareness and thinking related to better understanding of the links among trauma, pain and substance use. Practice changes included more active listening and empathy, less use of jargon and less judgement in care encounters. Participants linked these practices to better care interactions, and more trust, openness and satisfaction among service users.

Conclusion

Educating health professionals and others (e.g. educators) about trauma, violence, and discrimination is not easy. TVIC education can help shift potentially stigmatizing attitudes which can then precipitate practice change. These approaches are emerging as an important way to improve health and quality of life.
An opportunity for the tracked
Authors: Conway Basil
Published: February 2021

The following mixed methods research describes the impact of nineteen students who were given the opportunity to take honors mathematics courses during high school after previously being tracked into grade level courses in middle school. Quantitative results showed significant increases in students’ standardized state test scores when moved to the upper high school mathematical track. Quantitative results also indicate that the inclusion of these students did not affect those previously tracked. Qualitative results provide support for school personnel in understanding the effects of teacher expectations on student outcomes. Results inform and support researchers and policy makers to reconsider beliefs about tracking.
Effectiveness of educational interventions for health care staff to prevent and manage aggressive behaviors in patients admitted to an acute hospital: a systematic review protocol
Authors: Kynoch Kathryn , Ramis Mary-Anne , Liu Xian-Liang , Wang Mian , Mo Bei-Rong
Published: February 2021

Objective:

The objective of this review is to determine the most effective strategies for educating health care staff to manage or prevent aggressive patient behaviors within an acute care setting.

Introduction:

Health care workers in acute settings are frequently at risk of being injured by aggressive patients. Staff are often ill-prepared to de-escalate such behaviors and, therefore, are at greater exposure to verbal or physical injury. This protocol outlines methods for a systematic review on the effectiveness of educational strategies to manage and/or prevent aggressive patient behaviors in hospitals.

Inclusion criteria:

Quantitative studies that report on programs used to educate or train hospital staff in managing or preventing an episode of aggressive behavior by an adult patient while in an acute health care facility will be included. Individual, program, and organizational outcomes, such as confidence, behavior, knowledge, or attitudes, as well as recorded rates of injury, sick leave, stress, anxiety, or detection/prevention of aggression before and/or after the intervention will be analyzed. Psychiatric patients or settings are excluded from this review.

Methods:

Two reviewers will independently select and appraise eligible studies and extract data following methods outlined by JBI for systematic reviews of effectiveness. Multiple databases will be searched for studies in English and Chinese from 2008 to the present. The JBI System for the Unified Management, Assessment and Review of Information (JBI SUMARI) will be used to manage studies and, where possible, meta-analysis will be undertaken. Results will be presented in a Summary of Findings following the GRADE approach.

Systematic review registration number:

PROSPERO CRD42020190538
Stability of Rectangular Plates Elastically Supported at the Edges
Authors: Miles Aaron J.
Published: February 2021

The author points out that the exact solutions of stability problems of elastically supported rectangular plates involve the solution of a fourth-order partial-differential equation in conjunction with certain boundary conditions, and that the resulting expressions from which the critical loads must be obtained are clumsy transcendental equations. These equations contain as parameters the ratio of the stiffness of the beam to the stiffness of the plate and the ratio of the cross-sectional area of the beam to the cross-sectional area of the plate, as well as the number of half waves into which the plate buckles. The number of half waves must be an integer and of such value as to make the critical load a minimum. A set of curves, provided in this paper for the solution of these transcendental equations, gives the critical load and also the number of half waves into which the plate buckles.
Analysis of Plate Examples by Difference Methods and the Superposition Principle
Authors: Holl D. L.
Published: February 2021

In this paper the author applies the membrane analogs of H. Marcus to some elementary cases of thin homogeneous isotropic square plates having central-point loads and various boundary conditions. The analogy is made possible by two theorems: (a) The deflection of a membrane loaded with loads proportional to those on a given plate may be considered as the sum of the principal moments of the actual plate. (b) A second membrane may be loaded with elastic weights proportional to these moment sums and, subject to appropriate boundary conditions, the deflections of the latter membrane will be proportional to the deflections of the actual plate under the given loading system.

The principle of superposition of deflection surfaces or equivalent stress systems is utilized in this paper both by difference and differential methods. The problems treated are (1) a square plate with pinned or simply supported edges, (2) two opposite edges pinned and the other two free, (3) two opposite edges pinned and the other two clamped, (4) all four edges clamped, (5) all four edges free with only corner post supports. The correct critical stress at the center of the lower surface of the plate was obtained from special thick-plate theory for a particular thickness-to-span ratio. The effect of this critical stress on the whole plate action is depicted for various boundary conditions.
Forced Vibration in Nonlinear Systems With Various Combinations of Linear Springs
Authors: Den Hartog J. P. , Heiles R. M.
Published: February 2021

This paper deals with a single mass system containing a combination of linear springs having a force-displacement characteristic as shown in Fig. 1b. By varying the ratio k1/k2 of the spring constants, various modifications occur, e.g., for k1/k2 = 0 there is only one set of springs, and the system has a clearance x0 on each side of the equilibrium position; for k1/k2 = ∞ there is again a single set of springs which is now given an initial set-up force F.

The steady-state motion of these systems under the influence of a harmonic external force is wanted. Detailed exact solutions have been published for the cases k1/k2 = ∞ and k1/k2 = 0. In this paper these two special cases have been brought down to a simpler form, and two additional cases (k1/k2 = 2 and k1/k2 = 0.5) have been calculated. All these results, together with those of the classical linear case k1/k2 = 1 are shown in Figs. 5 to 9, inclusive, plotted in two different dimensionless forms.
An Electrical-Resistance Method of Determining the Mean Surface Temperature of Tubes
Authors: Marchant John H.
Published: February 2021

The author describes a new method for determining the mean surface temperature of condenser tubes through which a steady radial flow of heat occurs. The method consists in using the tube itself as a resistance thermometer. The author explains that when a steady longitudinal flow of electricity is superimposed upon the given radial flow of heat, the actual current being so small as not to involve appreciable Joulean heat, the temperature gradients associated with the flow of heat affect the electrical resistance of the tube material, and expressions for the mean temperature of the inner and outer tube surfaces can be derived from applications of physical laws. These expressions are derived by the author.
The Torsionless Bending of a Hollow Beam by a Transverse Load
Authors: Schwalbe W. L.
Published: February 2021

The author discusses the bending of hollow beams when subjected to transverse loads, and points out that shearing stresses and strains in the cross sections are necessary, and a particular longitudinal section remains plane only if the resultant of the shearing stress, and hence the plane of the applied bending moment, possesses a particular location. The author determines the location of this resultant shearing stress by applying a method based on St. Venant’s theory. Applications of the method are made to two hollow sections. One of the sections is that of an equilateral triangle which serves as a measure of accuracy for the numerical work presented by the author, since the location of the resultant of the shearing stresses is known by symmetry.
Buckling of Compressed Rectangular Plates With Built-In Edges
Authors: Maulbetsch J. L.
Published: February 2021

The author presents the results of a study made of two approximate methods available for determining the buckling load of compressed rectangular plates with built-in edges. One method gives values larger than the true buckling load, while the other method gives values smaller than this load, thus permitting an estimate of the approximation of the solution.
Effect of Temperature on Physical and Optical Properties of Photoelastic Materials
Authors: Lee G. H. , Armstrong C. W.
Published: February 2021

This paper reports the results of tension tests, to determine the suitability for photoelastic work, of five samples of Bakelite and two of Marblette at temperatures between 32 and 140 F. These results show the variation, of Young’s modulus, Poisson’s ratio, stress-optical coefficient, and strain-optical coefficient with temperature. Stress-strain curves of the materials are also given showing the relative amounts of creep. The effect of heat-treatment on Marblette is shown by tests before and after annealing.
Rubber Mountings
Authors: Downie Smith J. F.
Published: February 2021

This paper deals with static deflections of rubber mountings. An equation has been developed which correlates all the available data on plain rectangular slabs under compression loading. Data are given showing how closely this equation checks experimentation, and examples are solved, giving the method of using this equation and also the use of a chart simplifying the calculations. Additional data are given on other shapes of compression mountings.

The deflections of shear-type mountings are shown to agree with theory. Combination shear-compression units have also been tested.

Data are given showing the variation of hardness on the durometer A scale with change of temperature. At room temperature moduli of elasticity for compression and for shear are related with durometer hardness number, and the equations of these curves are derived.
A New Relationship for Use in the Design of Machine Columns
Authors: Clapp W. H.
Published: February 2021

The author discusses the requirements of an ideal formula for determining the stresses in machine columns and points out the fact that although the secant formula meets several of these requirements the relationships are so involved that it has always been necessary to use one of several empirical equations because of the uncertainty regarding the probable eccentricity of the load. The author describes a relationship which makes the secant formula usable and presents a universal chart adapted to the solution of problems of steel columns having any type of cross section when subjected to axial loading.
An Improved Method for Calculating Free Vibrations in Systems of Several Degrees of Freedom
Authors: Dudley Winston M.
Published: February 2021

In 1934 two English investigators (1) published a method for calculating the various modes and frequencies of vibration of a system having several degrees of freedom. Their method, which is based on matrices, greatly shortens the time spent in obtaining numerical solutions in many important problems, notably those with immovable foundations. In this paper is presented a new theorem which (a) makes possible a further reduction of nearly one half in the time required, so that solutions up to 20 deg or more of freedom are now practical and (b) makes it then possible to determine the motion of the system after any initial disturbance in a few minutes, instead of several hours as required by older methods. It is useful in the latter respect whether the modes have been determined by matrix methods, or not.

Although the paper gives simpler proofs than any previously published, knowledge of the matrix theory is not required in using the method. Problems are analyzed by a tabular process, in which an ordinary computing machine helps greatly. Comments based on computing experience are given. A simple numerical example has been given elsewhere (1).
Efficient Algorithm for Automatic Support Structure Generation in Layered Manufacturing
Authors: Hur Junghoon , Lee Kunwoo
Published: February 2021

Stereolithography is a process used to rapidly produce polymer components directly from a computer representation of a part. There are several considerations to be made for the efficient use of the process. Especially, the necessity of support structures, which prevent the part from warping, sagging, or parachuting and toppling as the elevator moves up and down in the resin, is one concern. After solidification, the support structures must be removed in the end. Thus the more the support structures, the more it increases the finishing operations. Especially for a complicated part, the removal operations may be difficult, take so much time, and even reduce the accuracy of the product. It is, therefore, important to efficiently generate the support structure for each part geometry. This paper proposes a algorithm to automatically generate the support structure focused on accuracy, efficiency, convenience, and generation speed. Besides, we can exactly determine an optimal build-up direction for the minimum volume of support structures.
A Workbench Architecture for Object Oriented Handling of Features
Authors: Horváth Imre
Published: February 2021

This paper is devoted primarily to the presentation and discussion of a novel architecture, called workbench, that facilitates application of system independent feature objects in various stages of mechanical design process. The motivation behind the development of this non-traditional architecture for advanced CAD/CAE systems lies in the necessity to (a) separate application oriented feature entities from the geometric modeling kernel, (b) increase the level of integration of functioning modules by supporting parallel processing and intercommunication, finally, (c) extend the scope of near-future systems to conceptual design in order to increase their influence on the technical and economic value of products. First, the paper gives an overview on the related research. Then, it presents the workbench architecture that consists of four main fundamental modules that are integrated, simultaneously active, and communicating. The library manager taxonomically classifies, retrieves and activates the existing feature-objects. The libraries of feature-objects contain generic entities for procedural modeling in conceptual design, shape design, manufacturing process planning, assembly planning, or other applications. The pool is an intermittent store of feature-instances that have been produced by procedural modeling based on the feature-object programs. The workspace provides graphical interactive tools for manipulation and positioning of, and composition with feature-instance geometries. The paper also discusses some implementation aspects.
Integration of Real IT-Applications in Virtual Manufacturing Systems
Authors: Gausemeier Jürgen , von Bohuszewicz Oskar , Gehnen Gerrit , Grafe Michaei
Published: February 2021

Modeling of automated manufacturing systems under conditions approaching reality by means of Virtual Reality technology is part of the Virtual Model Enterprise Project. It encompasses especially the integration of real information technology (IT) like CAD/CAM, PPS, or manufacturing control systems in the virtual environment, alongside the structural and functional reproduction of manufacturing systems.

The integration of real IT-applications in a virtual environment requires the realization of a data interface between VR-software and the IT-applications as well as the development of a suitable user interface to control the Application from within a Virtual Environment.

This contribution shows, in the case of the integration of a manufacturing control system in the existing production area of the Virtual Model Enterprise, how the previously described problems could be solved. Through the integration of the production management system, it is possible to apply the functionality of the manufacturing control to the virtual production and transport systems. This functionality encompasses the detailed planning of the tasks as well as the control and supervision of the virtual systems. The user is able to directly follow the process of the production tasks through the immediate visualization of the work process.
A New Viewfactor Algorithm Specific for Rectangular Enclosures
Authors: Collado F. J. , Marín J. M. , Minguijón R.
Published: February 2021

A new viewfactor algorithm valid for any pair of rectangles with all their edges lying parallel to some coordinate axis is presented in this paper. The new procedure is based on the projected contour method, making the best use of the simplicity of this geometry with many engineering applications. The main advantage of the new algorithm compared with other well known procedures, as the Mitalas-Stepheson one, is the great economy of execution time (almost three times faster) without loss of accuracy. Then, for more complicated cases with obstructions solved with clipping methods, where it is necessary to work out a large amount of contour integrals, the potential economy of CPU time is evident. Finally, a FORTRAN 77 subroutine coding the new algorithm is supplied.
Using VR for Design and Manufacturing Applications: A Feasibility Study
Authors: Angster S. , Gowda S. , Jayaram S.
Published: February 2021

Virtual Reality has been used for several years by architects to bridge the gap between their vision of the product and the finished product. Many of these applications use VR on a completed design and allow minor modifications to the design in the VR environment. This paper presents a feasibility study which was conducted to evaluate the accuracy of VR systems when used for conceptual design and in general, for engineering applications. A truck cab interior was modeled in a virtual environment and several ergonomic tests were performed in this virtual environment. The same tests were performed in a physical prototype of the truck cab and results of the two tests were compared. The virtual reality hardware and software systems used, the design evaluation scenario and the results of the tests are presented.
Modeling of Particulate Contamination in Tungsten Low Pressure Chemical Vapor Deposition
Authors: Busnaina Ahmed A. , MacGibbon Bruce S.
Published: February 2021

Chemical vapor deposition processes are one of the most used techniques for depositing thin films in the semiconductor-microelectronics and opto-electronic industries. Particulate contamination of the substrate during these CVD processes can be detrimental to the product yield. Due to the temperature gradients present in the CVD reactor, thermophoresis has a direct impact on the amount of particulate deposition on the substrate. The thermophoretic force is the force that arises from asymmetrical interactions of a particle with the surrounding gas molecules due to a temperature gradient. CVD processes can take place in hot and cold wall reactors, with varying substrate temperatures. This array of thermal boundary conditions results in a variety of temperature gradients and thermophoretic forces on the particle. There are other forces also acting on the particles in the CVD environment such as the Brownian force, drag, and gravity. The effect of thermophoresis on the particle transport and deposition in the reactor is examined. Different particle concentrations and sizes is considered in the reactor. The motion of these particles according to the thermal gradients in the reactor is examined. The behavior of these particles under different thermal conditions is studied.
Spacetime Optimization for Assembly Process Design Associated With Manual Lifting
Authors: Chang Chienchi , Brown Don R. , Bloswick Donald S.
Published: February 2021

This research develops a computer-aided system for health professionals which helps them to prevent injury related to manual lifting by workers in a manufacturing operation. The heart of the system is a computer program which prescribes the motion that a given person should follow while lifting an object according to different conditions. The system compares the prescribed path to the true motion data taken from a motion tracking system so the health professional can make suggestions on how the person should modify his/her movement.

The prescribed motion is generated with a new technique called spacetime optimization. The health professional describes the simplified characteristics of the human subject such as sex, height, weight, and harmful conditions that the subject should avoid, such as maximum low back stress or shoulder stress. He/she also describes the task involved, such as the starting and ending positions of the load, its shape and weight, and the positions of any intermediate obstacles in the path. The spacetime optimization engine generates the path that the person should follow in order to minimize the harmful conditions according to an objective function and constraints.

In this research, two dimensional dynamic human models are used and a graphical user interface is added to this system to display and compare the motion between real motion and simulation models.
Involute Gear Pumps Versus Lobe Pumps: A Comparison
Authors: Mimmi Giovanni C. , Pennacchi Paolo E. , Savi Carlo G.
Published: February 2021

In previous studies we have considered several types of positive displacement rotary pumps and deeply analyzed the generation of the flow rate and the design limits. This has been done in order to evaluate the main performance indexes: one of these, the flow rate irregularity, is related to the possibility that the pump becomes a source of vibration and noise. A second index is the specific flow rate, related to the delivery capacity of the pump.

In this paper, following our previous researches, we analyze internal involute gear pumps and internal lobe pumps, that have similar way to operate but different performances.

The design parameters and the way to optimize the performances are summarized for both cases. Finally a comparison between the two types of pumps is proposed, along with some optimum design cases.
The R&D of the Business Process Related Services of the Integrating Infrastructure
Authors: E Mingcheng , Cha Jianzhong , Dong Ming
Published: February 2021

Through analyzing the function requirements of the Business Process Related Services of the Integrated Infrastructure, this paper has studied the implementation strategy of BPRS by means of Object-Oriented method, matrix theory and Petri Net(PN) technology. Moreover, it has provided a system structure of BPRS based on Intelligence Engineering theory.
An Octree Algorithm for Dynamic Interference Detection Using Space Partitioning
Authors: Yu Yongxiang , Wu Minghua , Zhou Ji
Published: February 2021

This paper presents an octree algorithm for collision and interference detection using space partitioning technique. The technique greatly reduces the computation time consumed in dynamic collision detection during simulation progress. The simulated objects are represented in hierarchically decomposed octrees. Under this technique, the checking space can be partitioned according to the geometric dependence of two octrees, so that the relations (overlap or separate) among the nodes in the octrees can be determined directly. Since heuristic calculation is excluded from the algorithm, the time consumption for collision detection is greatly reduced.
Motion of Top Feed Mechanism of an Industrial Sewing Machine
Authors: Muramatsu N.
Published: February 2021

This study considered the motion of the top feed mechanism on lockstitch industrial sewing machines with alternating foot top feed and drop feed. The results obtained are as follows.

(1) The bounce phenomena of presser foot Ⓔ and walking foot Ⓖ is a spring reaction of said parts induced by the restoring force of feed dog Ⓕ or throat plate Ⓗ.

(2) The effects of the constituent factors that cause bouncing are as follows:

a. As the rotating speed increases and bouncing gradually increases, resonance occurs in the proximity of 1800 r/min.

b. There are certain ranges where the bounce of presser foot yp2 and walking foot yw1 decreases intermittently but sharply due to the uniformity in lightness of the mass mi (i = 1 to 7) of all constituent parts.

c. The bounce phenomena of yp2 decreases in direct proportion to the reduction of spring constant k1, of throat plate Ⓗ. On the other hand, that of yw1 shows minimal fluctuation.
Effective Design Methods of Wide Robust Structures
Authors: Hiroyasu Tomoyuki , Yamakawa Hiroshi
Published: February 2021

A structure, whose characteristics are less modified by any changes of external forces, boundary conditions and productive errors, has advantages for its practical use. This character is called robustness. In the consecutive study (Yamakawa and Miyashita, 1991), the authors studied the structural design with robustness and proposed a new structural concept called “Robust Structure.” Robust structural design is more useful when the structures are designed in the upper flow of the design process than in the lower flow. Robust structures can be designed by minimizing the sensitivities of the reference function relative to the variable parameters. However, the sensitivities provide only the local information even when their values are evaluated. Therefore, it is not clarified whether robust structure designed by the sensitivities has wide robustness or not. To conquer this problem, this paper shows robust structural design method using the fuzzy sets. In this method, the variable parameters are shown with fuzzy sets and then obtain the wide robustness. It is also pointed out that robust structural design using sensitivities can design wide robust structure in certain cases. Because robust structural design using fuzzy sets needs a lot of numerical iterations, it is important to figure out the effective design method of wide robust structures. In this paper, an idea is proposed how to design wide robust structures. The numerical examples designed by two different methods using sensitivities and fuzzy sets are shown. Further more, the proposed idea is discussed with these examples.
Two-Dimensional Sub-Micron Interferometric Detection of Geometric Translation Errors
Authors: Pegna Joseph , Hilaire Thierry P. , Clément André
Published: February 2021

In earlier papers [2][3] we showed how accurate position measurement and error propagation is completely characterized by a measurement plan. Among the various position sensor designs of interest, we pointed out that some spatially unresolved measurement plans are of particular value. Because the measurement plan is invariant for some degrees of freedom of the system, they offer an unusually large depth of field. The case in point is a measurement plan designed to capture the five components of motion errors for machine elements in translation. This paper focuses on the design of an optical sensor that makes this measurement plan feasible. High resolution translational error measurements over large depth of field were achieved due to a novel interferometer system. Design, implementation and testing are disclosed in this paper. The interferometer features the detection of transverse two-dimensional displacements in one measurement with a resolution of 80 nanometers over a depth of field up to one meter. The main originality of this interferometer is that it does not use wavelength, but rather the geometry of the fringe pattern to derive measurements. Thus the sensor was demonstrated to remain accurate under environmental variation that normally plague other interferometers. It is expected that this novel sensor design can refine resolution of precision machinery down to about 100 nm/m without the extent of environmental constraints and cost usually affiliated with the technology.
An Investigation Into the Performance of Cantilever Hook Type Integral Attachment Features
Authors: Luscher Anthony F.
Published: February 2021

Cantilever hook features are commonly molded into plastic parts as a inexpensive method of assembling several parts without separate fasteners. Insertion force, insertion dynamic strain, and retention force represent the critical performance data needed to design a cantilever hook for given loading conditions. This paper explores the performance of this feature under both insertion and retention using numerical and experimental methods.

A finite element model using contact and friction surface elements was used to simulate the actual insertion and retention processes of hooks. The design space for a hook was explored by using a design of experiments approach. Sensitivity information was obtained by tabulating main effects and interactions. For the goal of minimizing insertion force and maximizing retention strength, a balanced design was found which was sensitive to differing factors. Based on this data, generalized design rules for designing hooks were formulated.
Thermal Analysis of a New Metal-Deposition Rapid Prototyping Process
Authors: Worth Ronald K. , Barkan Philip
Published: February 2021

Rapid prototyping with solid free-form fabrication (SFF) is a key innovation that makes it possible to rapidly produce physical parts directly from a CAD model. Recent research focuses on SFF systems which directly fabricate metal parts. This paper introduces the Stanford Solid Plotter (SSP), a new SFF system that forms prototypes using metal-deposition. Since many critical problems in metal deposition relate to heat transfer issues, the main focus of the paper is on key aspects of the thermal behavior of the SSP part fabrication process, namely the deposition, freezing and cooling of a workpiece. Predictions from a finite difference heat transfer model are used to improve both the precision and strength of actual workpieces made with the SSP. Lab experiments using thermocouples confirm the behavior of the finite difference model.
Axiomatic Design Applied to Manufacturing Systems Design
Authors: Vallhagen Johan
Published: February 2021

In earlier work, the axiomatic design theory has been analyzed for applications on product design and the production processes that pertain to it, where parts manufacture and assembly take place in flexible and automatic manufacturing systems. The conclusion is that the original model cannot handle the manufacturing aspects in a satisfactory manner.

This report proposes an expansion of the axiomatic design model, with a life-cycle approach as take-off. The expansion of the model consists of the introduction of a so-called Manufacturing World with different spaces, where various types of processes and support functions can be developed in agreement with the axiomatic principles. The spaces and their relationships have been defined along with explanations of work procedures. An explanatory example is given.