bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhancing Neuroprosthetic Control through AI-Powered Adaptive Learning: A Simulation Study
Authors: Montgomery Richard Murdoch
Published: April 2024

Neuroprosthetic devices have the potential to restore motor function and improve the quality of life for individuals with limb loss or motor impairments. However, the control of these devices remains challenging due to the complex nature of brain-machine interfaces and the variability in individual brain wave patterns. This study presents a simulation framework that combines electroencephalogram (EEG) analysis with artificial intelligence (AI) to enhance the control and adaptation of neuroprosthetic devices. We simulate brain wave patterns across key motor regions, including the motor cortex, premotor cortex, supplementary motor area, parietal lobe, and cerebellum, during a simplified arm movement task. The simulation demonstrates the synchronization of brain waves over time, representing the neural dynamics underlying motor control. I propose an AI-powered approach that leverages machine learning algorithms to continuously learn from the user's brain wave patterns and adapt the control strategies of the neuroprosthetic device. The AI system enables personalized calibration, continuous learning, and improved movement control, leading to more intuitive and efficient use of the prosthesis. Furthermore, I discuss the potential for personalized feedback and training, as well as continuous upgrades and enhancements to the AI-powered neuroprosthetic devices. My simulation study highlights the promising role of AI in advancing neuroprosthetic control and lays the foundation for future research and development in this field. By harnessing the power of AI and adaptive learning, I envision a future where individuals with motor impairments can regain a higher level of independence and functionality through seamless integration with intelligent neuroprosthetic devices.
The Philippine Grains Standardization Program (PGSP) of the National Food Authority in Negros Occidental
Authors: L Gonzales Glenda
Published: April 2024

This study assessed the level of effectiveness of Philippine Grains Standardization Program (PGSP) of the National Food Authority in the areas of advocacy, quality standards, packaging, labeling, and color-coding, enforcement, and regulatory through data triangulation from among the external assessors and implementers in Negros Occidental. Moreover, when the program is assessed according to external assessors composed of millers, wholesalers, retailers, and farmers, they have evaluated the level of effectiveness of the program as an average while implementers assessed it as high. There was no significant difference in the level of effectiveness of PGSP in the areas of advocacy, quality standards, enforcement, and regulatory while there was a significant difference in packaging, labeling, and color-coding when grouped according to external assessors. On the other hand, when the assessors are grouped into implementers and external assessors, there was no significant difference in the level of effectiveness in the areas of packaging, labeling, and color-coding, enforcement and regulatory whereas, there was a significant difference in advocacy and quality standards. From the narrative of key stakeholders of the grains industry, PGSP has disclosed issues and gaps that need to deal with by the implementers to enhance its effectiveness. The result of the study was the basis for planning a proposed program for the enhanced implementation of PGSP in Negros Occidental.
Exploring the Use of Youtube as a Marketing Tool for Tourism Sector with Special Reference to Western Regions of India
Authors: Jyoti Nitin Dr. Pawar
Published: April 2024

Tourism and Hospitality, constituting one of India's largest service industries, hold significant sway in propelling the nation's growth and prosperity. As per WTTC data, the industry's contribution to the GDP has steadily risen, projecting around INR 16.5 trillion by 2023. Marketing stands out as a paramount management activity within the tourism realm, given the perishable and intangible nature of its products. The advent of digital marketing gained traction alongside the widespread adoption of the internet in the 1990s. Yet, one of the primary hurdles faced by digital marketers is distinguishing themselves in a landscape inundated with digital ads and various distractions. Online videos have long been capturing the attention of audiences, wielding substantial influence in the digital realm. YouTube Marketing emerges as the strategy for promoting businesses through videos and ads on the platform. With YouTube ranking as the world's second most popular website, boasting a vast and diverse audience, it presents significant opportunities for promotional endeavours. The present study tries to explore the use of YouTube as a marketing tool for tourism by the Government Tourism Development Corporations with special reference to Western regions of India.
The Role of Science Teachers in the Implementation of Quality School based Assessments in Selected Zambian Secondary Schools
Authors: Ireen Bwembya , Daka Harrison
Published: April 2024

The introduction of School based Assessments in Zambia were aimed at improving the teaching and learning as well as raise the bar of students performance in the country. However, the implementation of SBA in secondary schools faces unique challenges, particularly in the context of Zambia, exacerbated by the global COVID-19 pandemic. This study investigated the implementation of SBA in science subjects within selected Zambian schools, aiming to develop an evidence-based framework for sustaining the quality delivery of SBA in science education. Through a comprehensive investigation, this research examined the alignment of SBA practices with guidelines and identified gaps in implementation processes. Key objectives included assessing the evaluation of SBA policy since its rollout, examining administration processes, identifying challenges faced by stakeholders, and proposing interventions for improvement. Methodologically, the study employed tools such as questionnaires, interviews, and Focus Group Discussions to collect data. Qualitative data was analysed thematically while quantitative data was analysed using SPSS tool. Research findings revealed that teachers perceived SBA as a process of enhancing teaching and learning of science through the conduct of experiments which in turn improved teachers’ capacity and confidence in handling practical lessons. SBA provided teachers with an opportunity to closely monitor learners’ strengths and weaknesses as well as checking progress of learning. However, a considerable number of teachers held that SBA was an additional load onto their already burdened schedules but mandated to implement it as it was policy. Low staffing levels, time allocated to each science period, the number of tasks, inadequate laboratories and apparatus, resource constraints, high levels of enrolment resulting from positive response of Free Education Policy, many classes to teach by one teacher and lack of motivation, dominated the challenges faced by teachers in SBA implementation. The categorization of SBA revealed a duty-bound approach towards SBA (symbolic compliance), as SBA marks were mandatory for totalling learners’ final marks at the end of secondary school level. The study's recommendations aimed to enhance SBA implementation and foster positive educational outcomes. Furthermore, suggestions for future research include exploring the long-term impact of SBAs on academic performance, conducting comparative studies across different subjects, investigating technology integration, and exploring stakeholder perspectives. The research has contributed valuable insights to the discourse on educational assessment practices, providing a foundation for informed decision-making and strategic actions to improve science education in Zambian schools and beyond.
Weed Remover Using Machine Learning
Authors: Hema Swathi S
Published: April 2024

Weed Remover using Machine Learning is an innovative solution using machine learning techniques to address the persistent challenge of weed management in agriculture. The system integrates advanced machine learning algorithms with robotics to accurately find and cut weeds in real-time. A convolutional neural network (CNN) is trained on a diverse dataset comprising images of various crops and weed species, allowing the model to develop a robust understanding of visual cues associated with both. This trained model is deployed on a robotic platform equipped with cameras and actuators for real-time decision-making and precise weed removal
Sustainability of Medtronic Surgical Devices
Authors: Pille Mallory
Published: April 2024

Background

Medical devices used in surgery have the potential to impact the environment.  While it is essential for medical devices to be accessible, of quality design & manufacture, and cost effective, they must also aim at inducing the lowest environmental impact.  Industry partners have a role in advising on end-of-life pathways and designing devices that lessen their impact on the environment.

 

Methods

Medtronic has multiple initiatives underway to reduce the environmental impact of its devices from design pathways to commercial programs.  We summarize a few of the key surgical programs.

 

Results

Surgical staplers and energy devices are critical in many commonly performed surgeries.  Medtronic’s Signia™ powered stapler has a reusable battery and can be used for 300 procedures, whereas the competitor’s powered stapler is used for one procedure.  Similarly, Medtronic developed stapler reloads such as Tri-Staple™ reinforced reload with pre-loaded buttress material that not only reduces the clinical workflow demands but also reduces packaging waste compared to competitor buttress products that are sold separately.  Medtronic’s Sonicision™ 7 cordless ultrasonic dissection device features a reusable generator and battery pack, whereas the competitors’ is single use with a large, bulky generator.  Medtronic offers a LigaSure™ vessel sealing device collections program to ensure appropriate end-of-life pathway for the device.

 

Conclusion

Medtronic is playing a critical role in reducing the environmental impact of its devices while meeting customers’ needs and quality expectations.
Acute Appendicitis in Rural KwaZulu-Natal, South Africa
Authors: Clarke DL , Naidoo M , KONG VY
Published: April 2024

Abstract

The Lancet commission on Global Surgery identified a huge global burden of surgical illness which is not adequately treated, as the resources needed to effectively treat these many common surgical conditions are not readily available in many regions. This review aims to provide a comprehensive overview of the epidemiology, management, and outcomes of acute appendicitis in South Africa.

Methods

A scoping search was conducted across major electronic databases to identify relevant studies published between January 2000 and December 2023. Articles reporting on the incidence, presentation, diagnostic methods, surgical interventions, and outcomes of acute appendicitis in South Africa were included.

Results

The literature review revealed an increasing incidence of acute appendicitis among African patients in South Africa, potentially linked to dietary changes accompanying urbanization. Despite advancements in surgical techniques, open appendectomy remains the primary approach, particularly in public healthcare facilities, indicating disparities in access to laparoscopic surgery. Complications such as wound infections and hospital-acquired pneumonia contribute to prolonged hospital stays, high morbidity, and high mortality. However, outcomes in private healthcare settings demonstrate higher rates of laparoscopic procedures and lower complication rates compared to public institutions.

Conclusion  

Acute appendicitis in South Africa presents unique challenges, including disparities in surgical access and outcomes between public and private healthcare sectors. Addressing these challenges requires efforts to improve healthcare infrastructure, enhance surgical training, and promote equitable access to laparoscopic techniques. Collaborative research endeavors and evidence-based interventions are essential for optimizing the management and outcomes of acute appendicitis across diverse socio-economic contexts in South Africa.
Appendicectomy in sub-Saharan Africa: a tale of too many and too few
Authors: Adisa Adewale
Published: April 2024

The gold standard treatment for acute appendicitis remains appendicectomy, despite ongoing debates regarding the necessity of surgical intervention. In sub-Saharan Africa, there is a perceived increase in the incidence of acute appendicitis. However, evidence indicates that a significant proportion of affected individuals do not undergo timely appendicectomy, with estimates suggesting that 60-76% of cases remain untreated.
The ‘great unknowns’ in management of appendicitis in children.
Authors: Hall Nigel
Published: April 2024

Acute appendicitis is the commonest surgical emergency in children. The lifetime risk of developing appendicitis is 7-8% with a peak incidence in the early teenage years. As such over 10,000 children in the United Kingdom alone develop appendicitis annually. Given the abundance of cases and the frequency with which surgeons and other clinicians encounter children with appendicitis one might think that we know with certainty how to best to assess and treat young people suspected of having this condition.
Creating Impact in Surgery
Authors: Bhangu Aneel
Published: April 2024

Thank you for reading the latest edition of Impact Surgery. We are committed to fostering a platform that amplifies the voices and experiences of surgeons and researchers from across the world. In line with this vision, we are seeking pilot studies, global surgery studies, quality improvement projects, reviews, education, and deeper dives on surgical topics that are often overlooked or neglected elsewhere. We recognise the profound impact of surgical interventions on individuals, communities, and societies worldwide, and we hope to speed up solutions and policy changes to address the unique challenges faced by diverse populations.
Influence of sand grain size on the nest escape of green sea turtle hatchlings
Authors: Chong Lyvia , Booth David T. , Rusli Mohd Uzair
Published: April 2024

Sea turtle hatchlings rely on their finite energy reserve to sustain embryonic development in underground nests and during the first few days of their post-hatch life, including nest escape, beach crossing, and swimming offshore. This study aimed to investigate if the grain size of the nest substrate has an impact on green sea turtle (Chelonia mydas) hatchlings’ energy usage during nest escape. About-to-hatch green sea turtle eggs were incubated in laboratory chambers filled with either coarse-grain sand (φ = 0.507 phi) or fine-grain sand (φ = 2.028) at a temperature of 28oC. Open-flow respirometry was used to measure the hatchlings’ oxygen consumption rate during nest escape, which was then converted to energy consumption values. Results showed that hatchling morphology, hatching success, emergence success, and synchronous emergence rate were not significantly different between the groups of hatchlings in coarse versus fine sand. Hatchlings that dug through coarse sand emerged significantly faster (168 ± 13.9 h) than those in fine sand (233.21 ± 12.6 h) (t (26) = –3.473, p = 0.002). Additionally, the hatchlings in coarse sand (310.55 ± 28.1 kJ) consumed significantly less energy than hatchlings in fine sand (474.85 ± 64.7 kJ) (t (17.739) = –2.328, p = 0.032). A difference in amount of energy reserve upon emergence was detected between coarse and fine sand groups. To improve hatchery management practices, relocating “doomed” clutches into coarse sand (φ = 0.507) could potentially maximise the hatchlings’ energy reserve.
Evaluating the social welfare model of Vietnam: An introductory overview
Authors: Mahadew Bhavna
Published: April 2024

The focus of this article is on the social welfare model of Vietnam in an evaluative manner, with the aim of introducing this system to researchers and academics. It is argued that the right to social welfare is a fundamental human right as prescribed by the United Nations and Article 34 of the Constitution of Vietnam. Against this backdrop, this article first provides an overview of the current social welfare model in Vietnam, with a particular focus on domestic legislation. Fundamentally, it is noted that this system is based on four pillars: employment, income, and poverty reduction; social insurance; social assistance for individuals in exceptionally difficult situations; and guaranteeing a minimum level of access to certain basic social services. Secondly, the article evaluates the ways in which the government plans to improve this system based on their outlook for 2021–2030. This is fashioned on five pillars, namely: 1) the labor market, employment and income, supply and demand, infrastructure and projections for the labor market, labor market data, and employment services; 2) social insurance, encompassing mandatory, supplemental, and elective plans; 3) social assistance, encompassing emergency and ongoing help as well as social care; 4) a social welfare floor with a “basket” of necessities; and 5) expert social work for social welfare. Finally, the article underlines the way forward for Vietnam to materialise the aim of ameliorating their social welfare system through human rights and sustainable development.
Keaktifan Siswa pada Organisasi Siswa Intra Sekolah Terhadap Prestasi Belajar Siswa di SMA Negeri 3 Bulukumba
Authors: Ira wahyuni  , Rijal Abdul , Samsinar
Published: April 2024

This research aimed to determine the effect of student activity in intra-school student organizations on student achievement at SMA Negeri 3 Bulukumba ini the 2021/2022 academic year. The variables in this study are (1) student activity in intra-school student organizations as the independent variable (X), and (2) learning achievement as the dependent variable (Y). The population in this study are all students of the MPK/OSIS management at SMA Negeri 3 Bulukumba, totaling 36 students. The sampling technique used was the saturated sample technique, all members of the population were used as samples, namely 36 students. Data collection techniques used are questionnaires and documentation. The data analysis technique used is instrument test, classical assumption test, and hypothesis testing. The instrument test consists of a validity test and a reliability test. Classical assumption test consists of normality test, heteroscedasticity test, and linearity test. The hypothesis test consists of simple linear regression, t-test, and coefficient of determination (r²). Based on the results of descriptive analysis, student activity in intra-school student organizations is in the very good category and learning achievement is in the good category. From the results of simple linear regression analysis, the equation Y = 50.014 + 0.541 X, which means that for every 1 additional student activity value in intra-school student organizations, the learning achievement value has increased by 0.541 units. Meanwhile, from the t-test results obtained a significant value of 0.000 <0.05 percent, which means that student activity in intra-school student organizations has a positive and significant effect on student achievement, thus the hypothesis is accepted. Meanwhile, from the analysis of the coefficient of determination (r²) the value of r² = 0.770 or 77 percent means that student activity in intra-school student organizations has an influence on student achievement by 77 percent while the remaining 23 percent is influenced by other factors.
Analisis Laporan Keuangan untuk Menilai Kinerja pada PT. Bank Mandiri Taspen Cabang Makassar
Authors: Andi Alamsyah Saputra  , Ryketeng Masdar
Published: April 2024

This study aims to determine the effect of solvency, profitability, leverage, and firm size on the accuracy of financial statement submissions. The research was conducted at the company PT. Bank Mandiri Taspen Makassar Branch for the 2017-2019 period. The more precise the financial statements are submitted, the more useful the information presented will be for users in making decisions. The sampling technique used was the purposive sampling method. The results showed that the submission of the financial statements of PT. Bank Mandiri Taspen Makassar Branch and company size have a positive effect on financial performance at Bank Mandiri Taspen Makassar Branch. While solvency, profitability, and liquidity have no effect on financial performance.
Bergen, Tuskegee, Guatemala. Experimentación (in)humana con humanos: una mirada desde la Antropología Filosófica y Bioética en la era de la Medicina-basada en Valores
Authors: Martí-Carvajal Arturo
Published: April 2024

El objetivo es describir los experimentos humanos —sin consentimiento de los pacientes— en las ciudades de Bergen (Noruega), Tuskegee (Alabama, EE.UU.) y Ciudad de Guatemala, como un imperativo categórico rescatarlos de la oscuridad bibliográfica.  Se relatan con una mirada desde la era de la Medicina-basada en Valores. Se interrelacionan los deleznables acontecimientos con la bioética y la antropología filosófica para intentar la prevención de que hechos como los narrados puedan volver a suceder. ¡Primero, no hacer daño!
Composite Floor System for Sears Tower
Authors: Iyengar S.H. , Zils J.J.
Published: April 2024

Structural floor systems in high-rise steel buildings have usually taken the form of composite or non-composite rolled beam stringers which are spaced at 8 ft to 10 ft centers. In most cases, these stringers frame into moment-connected girders which are part of the traditional plane-frame system. The span of the stringer is governed by the economically feasible frame span and generally ranges from 20 ft to 40 ft. Therefore, the economic potential of floor systems beyond the 40 ft span for high-rise buildings has been inhibited to a large extent by the inefficiency of rigid frames over long spans in resisting lateral loads. Also contributing to the inefficiency is the indirect mode of load transfer from stringer to frame grider to columns. The design procedures for the most part have centered on determination of an acceptable frame span on the basis of required lateral resistance; the stringer system is then filled into this framework. The floor stringer subsystem has, therefore, played a secondary role in overall system optimization.
Discussion: Fire Resistance of Protected Steel Columns
Authors: Stetina Henry J.
Published: April 2024

Discussion
Yield Line Analysis of Column Webs with Welded Beam Connections
Authors: Stockwell Jr. Frank W.
Published: April 2024

In welded construction the connections, for the most part, are easily designed and fabricated. However, one of the more difficult connections occurs when a beam must be welded to a column web. This is so for two reasons: (1) analyzing the column webs capacity is arduous and (2) making the actual connection in accordance with the design is no simple task because of the space restrictions imposed on the welder by the column flanges. This paper will deal only with the first consideration—analyzing the column web strength—using Yield Line Analysis. The Yield Line approach has been utilized previously by Abolitz and Warner1 for brackets welded to column webs, and by Blodgett for welding rolled sections to box columns. The assumptions used here differ somewhat from those of the above authors. The final result is a series of curves covering a very high percentage of restrained beam to column web connections involving hot rolled shapes. The curves relate beam moments to column web thickness for a series of beam sizes and for W14 columns with yield strengths of 36 and 50 ksi. For special cases not covered by these curves, but for which the yield line pattern assumed is valid, direct solutions may be developed by use of the formulas used to construct these curves.
Cable-Stayed Bridges
Authors: Podolny Jr.
Published: April 2024

In recent years, effects of wind action and oscillation have been investigated very thoroughly for suspension bridges; such analyses are also required for cable-stayed bridges. Purely mathematical analysis of this problem is impractical at this time, so that model testing is used instead. It has been indicated that because of inherent system stiffness and damping, the cable-stay system is not as sensitive to wind oscillations as a conventional suspension system. Further, it has been indicated that vortex shedding and bending and torsional oscillation can be minimized with streamlined deck cross-sections. However, these conclusions are generalizations based upon data available from tests conducted on relatively few structures and it is felt that wind tunnel tests are essential for any given major cable-stayed structure. As has been indicated, the cable-stayed bridge type is one that is certainly competitive with other type structures up to 2,000 ft spans and possibly larger spans. There is certainly the potential for this type of structure to become economically favorable in the long span ranges dominated by the suspension bridge. In the authors opinion, it is a foregone conclusion that as more designers and State Highway Departments become aware of the advantages and potential this type of structure has to offer, a greater number of cable stayed bridges will appear on the American bridge construction scene.
Simplified Approach to AISC Bending Formulas
Authors: Stockwell Jr.
Published: April 2024

In Section 1.5.1.4.6a of the AISC Specification1 there are three equations for determining the allowable bending stress in a beam, and the equations to be used depend on the l/rT limits of the beam in question. However, where Cb is greater than one, or for other steel strengths, these equations must be used to determine Fb. In looking at Formulas (1.5-6a) and (1.5-6b) and at their corresponding l/rT limits, it can be noted that all numerical constants are 510 x 103, or multiples thereof. Further, these same expressions contain the variables Fy and Cb, except for Formula (1.5-6b) which is independent of steel strength. Thus, with all of these common terms it would appear that there exists a procedure wherein the mathematics involved could be simplified. To develop that procedure is the intent of this paper.
Simplified Seismic Drift Analysis of High-Rise Steel Frames
Authors: Fleischer Walter H.
Published: April 2024

After a simplified method for estimating motion amplitudes of high-rise steel frames under wind forces had been published in this periodical1 about two years ago, the question invited itself if the general approach used in that paper could also be employed to obtain drift statements for high-rise steel frames under the application of seismic loads as prescribed in the major building codes. This paper answers the question in the affirmative by demonstrating how the practicing engineer can estimate seismic drift amplitudes under code seismic forces very quickly and without the use of a computer by applying the following simplifying assumptions which have been demonstrated to be valid for use in preliminary design, yielding results of excellent accuracy.
Innovative Approaches to the Erection of Tension Roof Structures
Authors: Thornton Charles H. , Cuoco Daniel A.
Published: April 2024

With todays increasing use and acceptance of tension systems for roof structures, and the advanced analytical techniques utilized in conjunction with the computer, new and innovative types of tension structures have been inspired. These range from single- and double-layer cable systems to multi-directional grid networks to free-form structures having unique cable configurations. In order to construct these new types of roof structures in a practical manner, innovative approaches for erection are often generated. Unlike framed, rigid structures, most tensile structures are quite flexible and thus exhibit large movements, especially during erection. As a result, special care must be taken in the development and implementation of the erection of the structure. Another factor that must be considered is that the tensile structure usually requires a pretension of some magnitude to make it function as conceived. This is particularly true due to the relatively low stiffness which most tensile elements possess compared to framed flexural systems present in the same structural assembly. This need for pretensioning adds another dimension to the erection, i.e., jacking of one type or another.
One Engineers Opinion (Interaction Equations)
Authors: Stockwell Jr.
Published: April 2024

One Engineers Opinion
Directional Moment Connections--A Proposed Design Method for Unbraced Steel Frames
Authors: Disque Robert O.
Published: April 2024

Present practice in both elastic and plastic design of unbraced frames often results in uneconomical structures. This is because both methods require fully rigid connections. As a result, columns must be designed to resist beam gravity moments and connections must be able to develop the full moment capacity of the girders. Unfortunately, columns are not efficient members when resisting moments and full moment connections are often expensive, especially if column stiffeners are required. This paper proposes a simple new design procedure which eliminates the need for fully rigid connections in unbraced frames. Based on a more realistic analysis of the loading-unloading behavior of beam-to-column connections, the procedure results in more efficient connections and columns and, at the same time, permits the girders to be utilized to their maximum strength and stiffness. This method also rationalizes the long established elastic design method of "flexible wind connections" (the apparently paradoxical design method whereby the girders are designed as simple beams, the connections are designed for wind moment only, and no additional moments are assumed to be induced in either the connection or column by gravity loads on the girder.) Included in this paper is a rational method for determining the effective length of columns in unbraced frames when the connections are designed for a moment capacity less than that of the girder.
Discussion: Commentary on Highly Restrained Welded Connections
Authors: Jones Norman B. , Milek W.A.
Published: April 2024

Discussion
Drift Reduction Factors for Belted High-Rise Structures
Authors: McNabb J.W. , Muvdi B.B.
Published: April 2024

Reduction of drift in high rise structures is necessary to prevent unsightly plaster cracks and minimize the psychological effects of unnerving movements and frightening noises. The purpose of lateral load bracing systems is to resist lateral forces due to wind and earthquake. Wind or seismic bracing systems may be classified as X brace, K brace, knee brace, and rigid frame. These systems are used in building core regions, as between elevator or duct shafts and adjacent to passageways or corridors. Shear walls are often selected for structures with large column spacings when lateral forces can no longer be resisted by the floor slabs alone. The extent of joint fixity provided by connections becomes a primary consideration in the design of rigid frame bracing.
Seismic Design Practice for Steel Buildings
Authors: Teal Edward J.
Published: April 2024

To properly interpret seismic codes and their revisions, it is becoming increasingly important that the design engineer have an understanding of the basic theory behind seismic code provisions. This paper provides a brief treatment of the subject of seismic theory and design, particularly as it applies to structural steel. Much of the theory is condensed into simple terms more readily applied to the typical problems faced by busy design engineers. Specific seismic code provisions are discussed, to aid in their interpretation. The author has specifically addressed the situation of engineers designing for the earthquake problems and building codes of the State of California. No attempt has been made to cover conditions not applicable to California. However, it is hoped that the paper will prove helpful to any engineer involved in the seismic design of steel buildings.
Stiffness Design of Unbraced Steel Frames
Authors: Cheong-Siat-Moy F.
Published: April 2024

In considering the serviceability of unbraced multistory steel buildings at working loads, the ability of the bents to limit lateral deflections is of prime importance. The parameter most commonly used in the measurement of their stiffnesses is the frame drift index, which is defined as the sway recorded at the uppermost level of a frame divided by its total height. To control cracking in light partitions and in windows, the frame drift index is not an appropriate criteria to use. A more suitable indicator would be the story drift index, which is the ratio of the relative sway of a story to its height. This is so because story deflections are non-uniform and generally vary markedly throughout the frames height. In most conventional frames, improving beam inertias will efficiently reduce lateral sway; however, in some cases it is more desirable to increase column sizes and beam sizes simultaneously. This paper provides simple guidelines in deciding which course of action to take. The method is simple, fast, direct, and suitable for dealing with first-order as well as second-order deflections.
Rapid Selection of Beam-Columns for Wind or Earthquake Effects
Authors: Fiesenheiser E.I. , Ronan J.G.
Published: April 2024

Many floor beams, particularly those along column lines, are subjected to axial forces due to wind or earthquake effects together with bending due to floor loads. The use of the AISC formulas for this case is somewhat involved and time-consuming. The bending stress depends upon resistance of the compression flange to lateral buckling over unsupported lengths, whereas the allowable axial stress is governed by the slenderness ratios. The Kl/r values also depend upon locations of restraint points. Further, all allowable unit stresses are increased by one-third. One of the difficulties is that both slenderness ratios need to be taken into account simultaneously. The charts in this paper presented will expedite economical selections, since the curves cover the essential investigations of AISC Specification Sect. 1.6—Combined Stresses, when bending occurs only about the x-axis. Any member stressed to its full moment-carrying capacity will also have an additional axial load capacity which should be utilized. This is the additional strength fa which is given by the charts.
Discussion: Design Example for Beams with Web Openings
Authors: Redwood R.G.
Published: April 2024

Discussion
Fracture and Fatigue Control in Steel Structures
Authors: Rolfe S.T.
Published: April 2024

Considerable effort has been devoted to the prevention of brittle fracture in manufactured structures such as aircraft and pressure vessels, where large numbers of essentially identical structures are fabricated under closely controlled conditions. For example, the emphasis on safety and reliability of nuclear pressure vessels and the ensuing extensive research, as well as stringent controls, have led to a situation where the probability of a brittle fracture in a nuclear pressure vessel is virtually zero. For other types of manufactured structures, the causes of field failures usually can be remedied by changes in design of subsequent units. In contrast, other types of structures, such as bridges and buildings, are often individually designed for a specific function and location. The overall service experience of steels in these structures has been excellent, so that the designer in the past has seldom concerned himself with notch-toughness as a design parameter. However, the trend in structural design has been such that the following changes have occurred.
Discussion: Rapid Selection of Column Base Plates
Authors: Bird William R.
Published: April 2024

Discussion
Discussion: Drift Reduction Factors for Belted High-Rise Structures
Authors: McNabb J.W. , Muvdi B.B.
Published: April 2024

Discussion
Errata: A New Design For Torsion Resistant Suspension Bridges
Authors: Samelson Harold
Published: April 2024

Errata
A Practical Method of Second Order Analysis Part 2; Rigid Frames
Authors: LeMessurier William J.
Published: April 2024

In Part 1 of this series, a method was developed for performing second order analyses of pin jointed systems. A key concept of the method involved the lateral stiffness parameter lateral force which was defined as the force applied at the end of a member or subsystem that produces unit rotational displacement of the member or subsystem. This paper has developed a method for analyzing one-story rigid frames and multistory frames which are reasonably regular from floor to floor.
Errata: Effective Length of Columns with Semi-Rigid Connections
Authors: Driscoll Jr.
Published: April 2024

Errata
The Mysterious One-Third Stress Increase
Authors: Ellifritt Duane S.
Published: April 2024

It has been customary throughout three or four generations of structural engineers to use a higher allowable stress when considering the stresses produced by wind in a structure. Much later, the same provision was allowed for earthquake related stresses. Recently, this increase has come under attack from many quarters and there has been some confusion as to what was the rationale for permitting this increase in the first place. Just what physical phenomenon is it supposed to account for? When was it first introduced and why? If it was valid at the time of its origin, is it still valid today? The criticism has come from various sources. For example, engineers on the west coast have been lobbying to get rid of the provision for several years, primarily for earthquakes, but wind usually gets caught up in the fervor. Each year some building official proposes to the Uniform Building Code that the increase be abolished for both earthquake and wind. Each year the proposal is defeated. Since the earthquake provision came later and was probably borrowed from the wind provision, let us remove earthquakes from consideration here and investigate the validity of the permitted stress increase for wind only.
End Restraints on Steel Joist Floor Vibrations
Authors: Wang Leon Ru-Liang , Carrle Gunther
Published: April 2024

The problem of perceptible vibrations in steel joist/concrete slab floor systems has been under investigation for nearly 20 years. The vibrations, which can prove to be annoying to occupants, occur as a result of a human footfall. The floors, although structurally safe, lack the flexural rigidity necessary to prevent noticeable oscillations. Two articles by Lenzen6 and Murray, which have presented detailed methods for attacking the vibrations problem, were the primary sources for the background information presented in this paper. The discussion that follows leads to a new method of controlling the floor vibrations problem by varying the rotational end restraints of the floor.
Seismic Drift Control and Building Periods
Authors: Teal Edward J.
Published: April 2024

General parameters of seismic drift control were discussed by the author in a 1975 article titled "Seismic Drift Control Criteria" in the AISC Engineering Journal. However, the confusion which still exists concerning building periods and drift control, particularly in relation to code seismic design, indicates that these subjects deserve more attention. Building period governs the behavior of structures when they are subjected to earthquake ground motions, even when the dynamic response of the structure is forced far into the inelastic range during some of the strong motion. Drift, or distortion, really governs the performance of a building in terms of damage both to the structural frame and to nonframe elements. The designer needs to have a good understanding of the factors affecting these subjects. Knowing the limiting parameters is therefore important.
Discussion: Simplified Design for Torsional Loading of Rolled Steel Members
Authors: Lin Phillip H.
Published: April 2024

Discussion
Errata: Fire Safety Of External Building Elements--The Design Approach
Authors: Law Margaret
Published: April 2024

Errata
Fire Resistance of Structural Steel
Authors: Lie T.T.
Published: April 2024

Because a factor of safety is incorporated in design calculations, load-bearing members in a building generally possess reserve strength. This gives the member resistance to extreme loads such as floor load concentrations, wind, snow, and earthquake, and at the same time resistance to fire. During a fire, the member may be exposed to heating at extremely high temperatures, and as a consequence its strength may decrease substantially in a short time. To prevent such loss of strength it is essential to protect the member against excessive temperature rise. One of the problems in selecting appropriate protection is the evaluation of its effect on the fire performance of the member. Usually, fire performance is determined by subjecting a member to a standard fire. In practice, however, the severity of fire conditions can vary over a wide range. It is desirable, therefore, to find some means by which the performance of a member in a standard fire can be used to assess its performance under fire conditions more representative of those that might actually be expected.
Plastic Design Aids for Pinned-Base Gabled Frames
Authors: Manolis George D. , Beskos Dimitrios E.
Published: April 2024

Single-span rigid steel gabled frames are widely used in the construction of structures covering large areas with no obstructions, such as industrial buildings, auditoriums, warehouses, etc. It is the intent of this paper to facilitate the design of such structures by offering charts for the ultimate strength requirements of the frameworks that comprise them. In the case of statically indeterminate structures, such as most rigid frames, the methods of plastic design are more rational procedures than their elastic counterparts and yield lighter, yet perfectly adequate, designs. Furthermore, it is possible to realize additional weight savings by using haunches at the eaves of the frame, which strengthen the structure, and by using different column and rafter sections that result in a more efficient distribution of material. Only pinned-base frames are investigated, since complete end fixity is not only difficult to achieve in practice, but is also expensive. Besides, in the case of a differential settlement, the results are less detrimental to the frame if the bases of the columns are pinned rather than fixed.
Discussion: A Fresh Look at Bolted End- Plate Behavior and Design
Authors: Agerskov Henning , McGuire W.  , Griffiths John D. , Wooten J.M. , Rimmer Norman W. , Krishnamurthy N.
Published: April 2024

Discussion
Optimum Design of Steel Pipe Racks
Authors: Arya Suresh C. , Feng Edward G. , Pincus George
Published: April 2024

The availability of user-oriented computer programs has had great impact on engineering analysis and design of structural systems. This computational tool can be useful not only to obtain fast and accurate values of forces and displacements in structural systems, but its usefulness has been extended to the economical (minimum weight) design of structural steel members and frames. The design phase can be made very efficient by following an optimization process when suitable computer programs are available. The optimization process may include a number of design constraints, such as: (a) attainment of overall minimum weight, (b) limiting the selection process to a given range of member sizes, and (c) limiting displacements to certain tolerable values. Current engineering practice often utilizes the capability of the computer for the analysis phase only, and considers the subsequent design process a professional art to be left to the discretion of the "Design Engineer." There are reasons for this distinction between analysis and design. For example, the application of a design code requires experience and judgment, the selection of member sizes should be practical, and there is usually a match among the selected member sizes. However, some computer programs available today are so versatile that they not only include code design criteria as built-in algorithms, but in addition the input procedure is relatively simple and easy to learn and apply. In fact, many engineers are able to understand the computer code in their first encounter with a coded problem even if lacking in prior computer experience.
Human Response to Wind-Induced Motion of Buildings (T.R. Higgins Award)
Authors: Hansen Robert J. , Reed John W. , Vanmarcke Erik H.
Published: April 2024

Some tall buildings sustain motions and other effects in intense wind storms which cause discomfort to the occupants. The results of surveys conducted of occupants of two buildings after several wind storms are given in detail. The writers propose a methodology and criterion format for rationally analyzing the wind-motion-discomfort problem for tall buildings. Finally, tentative motion criterion values, based primarily on the two occupant surveys presented, are proposed.
Efficiency of Tubular Framing for Medium-Height Buildings
Authors: Leffler Robert E.
Published: April 2024

A tubular-framed high-rise building has its main structural frame on its perimeter. The columns are closely spaced, so that the structural behavior of this perimeter frame will approximate that of a tube in resisting applied loads. 1 This type of framing is generally applied to tall structures with 40 or more stories, although it has been used for buildings as low as 22 stories. This is because its main advantage is in resisting wind loads, which become more important as the height of the building increases. Furthermore, shear lag, which reduces the effectiveness of the tubular frame in resisting wind loads, is smaller in tall buildings. To evaluate this framing method for medium-height buildings ranging between 20 and 40 stories, comparative designs were made of a 20-story building whose arrangement was representative of this type of structure. Three types of frames were compared: (1) a simple building frame, (2) a rigid building frame, and (3) a tubular building frame. Cost estimates were obtained for the latter two designs.
A Specification for the Design of Steel-Concrete Composite Columns
Authors: SSRC
Published: April 2024

Subcommittee 20—Composite Columns was designated in 1973 as a standing committee of the Structural Stability Research Council (formerly called the Column Research Council). With an abundant background of experience regarding steel column behavior, the Council recognized that steel-concrete composite compression members should behave almost the same as plain steel columns if, in composite cross sections, the strength and stiffness of the structural steel alone were several times greater than the strength and stiffness of the structural concrete. The Council was also aware that if, in a composite cross section, the strength and stiffness of the concrete alone were significantly greater than the strength and stiffness of structural steel, the composite compression member would behave much the same as an ordinary reinforced concrete column. Design concepts traditionally applied to structural steel involved fundamental differences from those generally applied to reinforced concrete. The consequences of unequal results from the different design concepts required reconciliation within a rational statement of recommended practice for composite column design.
Elastic Buckling of a Column Under Varying Axial Force
Authors: Shrivastava Suresh C.
Published: April 2024

When a truss or open-web steel joist is used as a frame member, parts of the bottom chord near the ends carry compressive forces and adequate bracing must be provided to prevent lateral buckling of the chord. The compression in the chord varies from panel to panel; the problem is to determine the buckling load factor for a given loading and assumed location of the bracing point. Although the problem can be solved exactly, a simple procedure is given herein which may be used in the design office for rapid, hand computation of the buckling load factor in the elastic range.