scholarly journals Beacon-Based Individualized Hazard Alarm System for Construction Sites: An Experimental Study on Sensor Deployment

2021 ◽  
Vol 11 (24) ◽  
pp. 11654
Author(s):  
Fansheng Kong ◽  
Seungjun Ahn ◽  
JoonOh Seo ◽  
Tae Wan Kim ◽  
Ying Huang
Keyword(s):  
Experimental Study ◽  
Concrete Structure ◽  
Target Location ◽  
Side Wall ◽  
Access Point ◽  
Alarm System ◽  
Front Side ◽  
Internal Wall ◽  
Study Approach ◽  
The Impact

Researchers have proposed several forms of beacon sensor-based hazard alarm systems for increasing construction workers’ awareness of site hazards, but research on how to deploy beacon sensors so that the system is adequate for achieving timely individualized hazard alarms is scarce. Against this background, this research investigates the impact of different beacon sensor locations in a construction site on how quickly a worker can receive the individualized hazard alarms. This research took an experimental study approach to address this objective. After a prototype of a beacon-based hazard alarm system was developed, the system was tested in a concrete structure building under construction. In the experiment, the locations where the experimenter received the first hazard alarm were recorded in repetitive trials while the beacon sensor was located in four different locations, such as (1) at the entrance of the room, (2) behind the front side wall, (3) on the internal wall facing the access point, and (4) on the internal wall not facing the access point and in a partially enclosed room in the concrete structure. The rate of successful alarm notification (i.e., the rate that the person received the hazard alarm before arriving at the target location) was 89%, 68%, 48%, and 19%, respectively, for the four locations of the beacon sensor. Meanwhile, the heat maps indicating where the hazard alarm notification was received show that the “behind the front side wall” setting yielded the most desired pattern of notification reception, wherein the person received the hazard alarm just before arriving at the room. These results show that the hazard alarm function of the system could be severely affected by the beacon sensor’s location and implies that the locations of beacon sensors should be decided carefully based on the type of hazard involved and the workers targeted for receiving the alarms.

Impact to Composite Box Containing Water and Baffles

2016 ◽  
Vol 139 (3) ◽  
Author(s):  
Y. W. Kwon ◽  
T. J. South ◽  
K. J. Yun
Keyword(s):  
Experimental Study ◽  
Water Level ◽  
Computational Study ◽  
Structural Response ◽  
Experimental Tests ◽  
Low Velocity Impact ◽  
Front Side ◽  
Low Velocity ◽  
Structural Responses ◽  
The Impact

A series of experimental tests were conducted for low-velocity impact on a composite box containing water in order to study the fluid–structure interaction (FSI). Then, baffles were inserted in the box to examine their effect on the structural response of the composite box. Finally, a computational study was conducted to supplement the experimental study. The water level inside the composite box was varied incrementally from 0% (i.e., no water) to 100% (full water). The impact velocity was also changed. In the experimental study, strain gauges and the load cell were used to measure the strain responses at the front, side, and back surfaces as well as the impact force. The results showed that the FSI effect was significant to the structural responses depending on the water level. The effect of the baffle was different among the front, side, and back surfaces. Both experimental and numerical results agreed well.

Experimental study of thermohydraulic characteristics and irreversibility analysis of novel axial corrugated tube with spring tape inserts

2020 ◽  
Vol 92 (3) ◽  
pp. 30901
Author(s):  
Suvanjan Bhattacharyya ◽  
Debraj Sarkar ◽  
Ulavathi Shettar Mahabaleshwar ◽  
Manoj K. Soni ◽  
M. Mohanraj
Keyword(s):  
Heat Transfer ◽  
Experimental Study ◽  
Thermal Performance ◽  
Working Fluid ◽  
The Novel ◽  
Heat Exchanger Tube ◽  
Heat Transfer Augmentation ◽  
Corrugated Tube ◽  
The Impact ◽  
Exchanger Tube

The current study experimentally investigates the heat transfer augmentation on the novel axial corrugated heat exchanger tube in which the spring tape is introduced. Air (Pr = 0.707) is used as a working fluid. In order to augment the thermohydraulic performance, a corrugated tube with inserts is offered. The experimental study is further extended by varying the important parameters like spring ratio (y = 1.5, 2.0, 2.5) and Reynolds number (Re = 10 000–52 000). The angular pitch between the two neighboring corrugations and the angle of the corrugation is kept constant through the experiments at β = 1200 and α = 600 respectively, while two different corrugations heights (h) are analyzed. While increasing the corrugation height and decreasing the spring ratio, the impact of the swirling effect improves the thermal performance of the system. The maximum thermal performance is obtained when the corrugation height is h = 0.2 and spring ratio y = 1.5. Eventually, correlations for predicting friction factor (f) and Nusselt number (Nu) are developed.

Prinsip Kearifan Lokal dalam Pengembangan Strategi Kehumasan pada Pemerintah Daerah Kabupaten Bandung

2020 ◽  
Vol 4 (2) ◽  
pp. 229-248
Author(s):  
Betty Tresnawaty
Keyword(s):  
Public Relations ◽  
Local Knowledge ◽  
Case Study Approach ◽  
West Java ◽  
Study Approach ◽  
Positive Image ◽  
The Government ◽  
The Impact ◽  
Public Relations Strategy

Public Relations of the Bandung Regency Government realizes that its area has a lot of potential for various local wisdom and has a heterogeneous society. This study aims to explore and analyze the values of local knowledge in developing public relations strategies in the government of Bandung Regency, West Java province. This study uses a constructivist interpretive (subjective) paradigm through a case study approach. The results showed that the Bandung Regency Government runs its government based on local wisdom. Bandung Regency Public Relations utilizes local insight and the region's potential to develop a public relations strategy to build and maintain a positive image of Bandung Regency. The impact of this research is expected to become a source of new scientific references in the development of public relations strategies in every region of Indonesia, which is very rich with various philosophies.Humas Pemerintah Kabupaten Bandung menyadari wilayahnya memiliki banyak potensi kearifan lokal yang beragam, serta memiliki masyarakatnya yang heterogen. Penelitian ini bertujuan menggali dan menganalisis nilai-nilai kearifan lokal dalam pengembangan strategi kehumasan di pemerintahan Kabupaten Bandung provinsi Jawa Barat.  Penelitian ini menggunakan paradigma interpretif (subjektif) konstruktivis melalui pendekatan studi kasus. Hasil penelitian menunjukkan bahwa Pemerintah Kabupaten (Pemkab) Bandung menjalankan pemerintahannya berlandaskan pada kearifal lokal. Humas Pemkab Bandung memanfaatkan kearifan lokal dan potensi wilayahnya untuk mengembangkan strategi humas dalam membangun dan mempertahankan citra positif Kabupaten Bandung.Dampak penelitian ini diharapkan menjadi sumber rujukan ilmiah baru dalam pengembangan strategi kehumasan di setiap daerah Indonesia yang sangat kaya dengan beragam filosofi. 

An Experimental Study on the Transport of Sediment in Sewer Pipes with a Permanent Deposit

1992 ◽  
Vol 25 (8) ◽  
pp. 115-122 ◽  
Author(s):  
G. S. Perrusquía
Keyword(s):  
Experimental Study ◽  
Critical Shear Stress ◽  
Side Wall ◽  
Bedload Transport ◽  
Flow Conditions ◽  
Sewer Pipes ◽  
Sediment Bed ◽  
Concrete Pipe ◽  
Geometric Factors ◽  
Particle Parameters

An experimental study of the transport of sediment in a part-full pipe was carried out in a concrete pipe. The experiments were confined to bedload transport. The purpose of this study was to analyze the flow conditions that characterize the stream traction in pipe channels and their relationship to flow resistance and sediment transport rate. Three procedures used in this kind of experimental study were tested and found valid: 1) the vertical velocity distribution near the sediment bed can be described by the velocity-defect law, 2) the side wall elimination procedure can be used to compute the hydraulic radius of the sediment bed, and 3) the critical shear stress of the sediment particles can be obtained by using Shields' diagram. A relationship to estimate bedload transport, based on dimensional analysis, was proposed. This was expressed in terms of both flow and particle parameters as well as geometric factors. Further experimental work is recommended before this relationship can be fully incorporated in a simulation model for the analysis of storm sewers.

Experimental study of heat transfer in the boundary layer of a flat plate with the impact of weak shock waves on the leading edge

2020 ◽  
Author(s):  
V. L. Kocharin ◽  
A. A. Yatskikh ◽  
D. S. Prishchepova ◽  
A. V. Panina ◽  
Yu. G. Yermolaev ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Boundary Layer ◽  
Experimental Study ◽  
Shock Waves ◽  
Flat Plate ◽  
Leading Edge ◽  
Weak Shock ◽  
The Impact

scholarly journals Study on improvement of prefolded energy absorption device to constant resistance and its mechanical properties

2021 ◽  
Vol 104 (3) ◽  
pp. 003685042110368
Author(s):  
Dong An ◽  
Jiaqi Song ◽  
Hailiang Xu ◽  
Jingzong Zhang ◽  
Yimin Song ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Energy Absorption ◽  
Compression Test ◽  
Side Wall ◽  
Concave Side ◽  
Displacement Curve ◽  
Static Compression ◽  
Constant Resistance ◽  
The Impact ◽  
Force Displacement

When the rock burst occurs, energy absorption support is an important method to solve the impact failure. To achieve constant resistance performance of energy absorption device, as an important component of the support, the mechanical properties of one kind of prefolded tube is analyzed by quasi-static compression test. The deformation process of compression test is simulated by ABAQUS and plastic strain nephogram of the numerical model are studied. It is found that the main factors affecting the fluctuation of force-displacement curve is the stiffness of concave side wall. The original tube is improved to constant resistance by changing the side wall. The friction coefficient affects the folding order and form of the energy absorbing device. Lifting the concave side wall stiffness can improve the overall stiffness of energy absorption device and slow down the falling section of force-displacement curve. It is always squeezed by adjacent convex side wall in the process of folding, with large plastic deformation. Compared with the original one, the improved prefolded tube designed in this paper can keep the maximum bearing capacity ( Pmax), increase the total energy absorption ( E), improve the specific energy absorption (SEA), and decrease the variance ( S2) of force-displacement curve.

An experimental study of Web switching behavior

2003 ◽  
Vol 22 (2) ◽  
pp. 87-93
Author(s):  
James Otto ◽  
Mohammad Najdawi ◽  
William Wagner
Keyword(s):  
Experimental Study ◽  
Electronic Commerce ◽  
Web Site ◽  
Waiting Times ◽  
Switching Behavior ◽  
The Internet ◽  
Wait Times ◽  
Web Page ◽  
Extensive Growth ◽  
The Impact

With the extensive growth of the Internet and electronic commerce, the issue of how users behave when confronted with long download times is important. This paper investigates Web switching behavior. The paper describes experiments where users were subjected to artificially delayed Web page download times to study the impact of Web site wait times on switching behavior. Two hypotheses were tested. First, that longer wait times will result in increased switching behavior. The implication being that users become frustrated with long waiting times and choose to go elsewhere. Second, that users who switch will benefit, in terms of decreased download times, from their decision to switch.

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