• Journal of rehabilitation welfare engineering & assistive technology
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• v.8 no.3
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• pp.197-203
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• 2014

In this paper, we develop an attachable head of bed(HOB) monitoring system, which can prevent ventilator associated pneumonia(VAP), and analyze the performance of the developed HOB monitoring system. The main purpose of the HOB monitoring system is to support visible HOB display for keeping patients' position effectively and collect data for analysis of the relation between HOB elevation and patients' symptom. The HOB monitoring system is developed in attached-type and uses an FIR filter with heuristic logic to remove the unwanted noise. The optical encoder is used for the performance analysis of the developed HOB monitoring system.

• Korean Journal of Computational Design and Engineering
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• v.1 no.2
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• pp.150-157
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• 1996

The hob is considered as an effective gear cutting tool for achieving the various gears such as spur gear, helical gear, worm gear and so on. To enhance the productivity and precision of hobs and the competitive ability of domestic CNC hob relieving lathes, a CAM system for CNC hob relieving lathe needs to be realized. In this study, the CAM system is developed based on the personal computer and C language. Besides the automatic generation of CNC data, the developed CAM system has the various capabilities related to the generation of tool path, the cutting simulation for verifying the generated CNC data and forecasting the cutting time, the DNC operation for communicating the CNC data with CNC controller by RS232C port, and the estimation of undercut length for verifying the hob cutting conditions.

• International Journal of Advanced Culture Technology
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• v.6 no.3
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• pp.211-215
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• 2018

Ventilator-associated pneumonia (VAP) is a lung infection that develops in patients receiving mechanical ventilation. VAP contributes to about 50% of hospital-acquired pneumonia in ICU settings. One of the recommendation of the Institute of for Healthcare Improvement ventilator bundle is HOB elevation. HOB elevation affects shearing forces and makes higher risk for pressure injury development. Pressure injury (PI) is localized damage to the skin over a bony prominence. PI prevention guidelines recommend that HOB positioning should be lower to reduce risk for PI development which contradicts VAP prevention guidelines for the HOB between 30 and 45 degrees for ICU patients. This presents a care dilemma and tension. The purpose of this study was to perform a secondary data analysis using cumulative electronic health record data in order to determine the association of HOB elevation with VAP and PI in ICU patients. A secondary data analysis was conducted to determine whether HOB elevation is associated with VAP and PI. HOB elevation was not likely to be associated with VAP prevention whereas it was likely to be related to PI development. This is somewhat contrary to popular data and publications. Prospective cohort study is desired to inform us in an evidence-based fashion what actually is optimal HOB elevation for ventilated patients in ICU settings.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.10a
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• pp.458-463
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• 1999

When designing a gerotor, designers determine basic dimensions of a gerotor with transmitted power considering strength, interference and so on. But, designers can not easily obtain the tooth profile generated by dimensions as well as the geometry of generating hob for cutting the tooth profile. In order to resolve these problems, an automatic design system creating not only the solid model of a gerotor but also that of the generating hob using the design parameters of dimensions is developed. Through the developed system, designers can improve the efficiency of design and satisfy the variable requirements of design as well. In this research, the three-dimensional solid model of gerotor is generated considering the design parameters. Besides, that of generating hob with respect to the design parameters of hob is created automatically. The system is developed using Visual Basic and its three-dimensional geometric modeling module is constructed using SolidWorks.

• Transactions of the Korean Society of Mechanical Engineers
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• v.12 no.6
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• pp.1312-1319
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• 1988

Internal gear is the important part of the planetary reduction gear system. This study aims at developing the numerical analysis method for design of spherical hob to manufacture internal gear. Methods of calculation of hob tooth profile, generating tooth profile and tooth profile errors such as the errors of pressure angle, tooth thickness and pitch of spherical hob must be made smaller than those of standard tooth profile. And, the smaller the pressure angle and the number of equivalent pinion tooth become, the larger the tooth profile errors are. One design example of spherical hob is proposed.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.1
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• pp.39-46
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• 2001

When designing a gear, designers determine basic dimensions of a gear with transmitted power considering strength, interference and so on. But, designers can not easily obtain the tooth profile generated by dimensions as well as the geometry of generating hob for cutting the tooth profile. In order to resolve these problems, an automatic design system creating not only the solid model of a gear but also that of the generating hob using the design parameters of dimensions is developed. Through the developed system, designers system, designers can improve the efficiency of design and satisfy the variable requirements of design as well. In this research, the three-dimensional solid models for spur and helical gears are generated considering the design parameters. Besides, those for generating hob regarding the design parameters of hob is created automatically. The system is developed by using Visual Basic and its three-dimensional geometric modeling module is constructed by using SolidWorks.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.3
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• pp.43-49
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• 2001

When designing a gerotor, designers determine basic dimensions of a gerotor with transmitted power considering strength, interference and so. on. But, designers can not easily obtain the tooth profile generated by dimensions as well as the geometry bob for cutting the tooth profile. In order to resolve these problems, an automatic design sys-tem creating not only the solid model of a gerotor but also that of the generating hob using the design parameters of dimen-sions is developed. Through the developed system, designers can improve the efficiency of design and satisfy the variable requirements of design as well. In this research, the three-dimensional solid models for gerotors are generated considering the design parameters. Besides, those for generating hob regarding the design parameters of hob is created automatically.

• Journal of Institute of Control, Robotics and Systems
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• v.21 no.11
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• pp.1038-1043
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• 2015

When the study on the relationship between the Head-of-Bed (HOB) angle and ventilator-associated pneumonia is performed, the fact that the HOB angle can only be measured intermittently imposes a significant limitation on the study. Therefore, there has been demand for the development of a device that can measure the HOB angle continuously. In this paper, we propose the rapid prototyping of an HOB measurement system using open-source hardware and software. The proposed system helps to maintain the HOB angle at a particular angle by displaying the angle and helps the medical study of pneumonia patients by enabling continuous data acquisition. Firstly, we eliminate the process of making an MCU board by utilizing an open-source hardware mbed LPC1768. Secondly, we reduce the software development time by using libraries and hence enabling the easy use of peripherals. Thirdly, for rapid prototyping, we build the enclosure of the proposed system using a 3D printer. The proposed system can be attached and detached to and from a bed. Therefore, we can attach it to the bed of a patient for whom measurement of the HOB angle is necessary. Finally, we check the measurement performance and the validity of the proposed system through an experiment utilizing an incremental encoder.

• Journal of Mechanical Science and Technology
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• v.14 no.4
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• pp.408-417
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• 2000

The design and simulation of meshing of a single enveloping worm-gear drive with modified surfaces is presented. Generally worm-gear is generated by the hob which is identical to the worm. This process guarantees the conjugation between the worm and the gear but results in a line contact at every instant which is very sensitive to misalignment. The localization of bearing contact is necessary to reduce the sensitivity of the worm-gear drive to misalignment. Practically this localization is achieved by application of an oversized worm type hob to cut the worm-gear. The oversized hob approach is very practical and effective to localize bearing contact but can not provide the conjugation between the worm and the modified worm-gear. This work proposes an analytical procedure to make the worm surface conjugate to the worm-gear which is cut by the oversized hob. The developed computer program allows the investigation of the influence of misalignment on the shift of the bearing contact and the determination of the transmission errors, the contact ratio and the principle curvatures. The developed approach has been applied for ZK type of single-enveloping worm-gear drives and the developed theory is illustrated with a numerical example.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.5
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• pp.848-854
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• 2012

SCM420 steel cutting gear to improve the durability is quenched. When quenching, increases surface hardness, a change of the physical properties and machinability or fall. This study, using a solid carbide hobs skiving hobbing gear cutting finishing. And cutting tool solid carbide TiAlN coating hove when TiAlN coating on the surface of multi-con polishing hob conducted aero lap nano polishing for each cutting. Experimental results conducted aero lap nano coating on the surface polishing tool machinability was excellent. And aero lap nano polishing tool results were reduced 2.5 times the tool wear compared to TiAlN coated tools. Excellent results were 1.42 times longer tool life.