• Title/Summary/Keyword: sound Quality

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The Study on ODD Acoustic Noise Reduction by Using Micro Muffler (마이크로 머플러를 이용한 ODD소음 저감에 관한 연구)

  • Moon, Byeong-Gi;Cha, Sung-Woon;Lee, Byung-Hee
    • Transactions of the Society of Information Storage Systems
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    • v.2 no.1
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    • pp.50-55
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    • 2006
  • As high performance and high speed have been accomplished by technology of optical disk drive. optical disk drives have gradually high percentage of the market share in market of storage devices. This technology helps to improve the quality of record/reproduction. However, simultaneously it causes various problems in the structural aspect and increases noise largely. Especially at high speed, dominant noise is more influenced by fluid noise than by structure-borne noise. The purpose of this study is that reduce the air-born noise in optical disk drive as it decreases a quantity of flow by using a micro muffler. The micro muffler is a miniaturized muffler. The muffler is used widely by solution to reduce air-borne noise which is generated by flow. According to frequency band of the noise source, it can be applied by muffler of various forms. In this study, we examined the acoustic characteristics of the micro muffler and applied it to reduction of the ODD noise. It could get an excellent noise reduction in high frequency band through the decrease of an inner flow. But it could not get a noise reduction in low frequency band.

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A Study on Noise Characteristics in the Running Train of the Urban Railway (도시철도 영업운행열차 내 소음에 관한 고찰)

  • Kim, Hyo-San;Lee, Chang-Hun;Kim, Gwang-Eun;Lee, Gyu-Chon;Park, Jin-Dong
    • Proceedings of the KSR Conference
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    • 2008.11b
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    • pp.93-99
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    • 2008
  • The SeoulMerto, operating subway line No.$1{\sim}4$, was constructed in the metropolitan Seoul with the highest population. When it was built, the design was challenged to sharp curved tracks considering the protection of buildings, cultural assets, the connection to ground roads and rivers as well as to elevated railway in some parts. Lots of residential apartments and business complex have gradually increased in the area around subway stations and railway lines according to the urban development. Consequently, Requirements of better quality of life and comfortable environment caused the citizen complain for the noise. It has become one of serious social issues. In this paper, Noise level was analyzed using noise map measured in the running train of all routes. The analysis on the noise level was conducted according to railway type, track components type, seasonal type, retirement degree of the vehicle and subway station. Especially, Noise characteristics were analyzed by noise level data measured in the inside and outside of the train with geometry types of the concrete track. This study will contribute fundamental data for the "The Development of Sound-Absorbing Block on Concrete Track" promoted on The National R&D Project.

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Design and Implementation of Multi-monitoring System for Motor Pump (모터 펌프를 위한 멀티-모니터링 시스템 설계 및 구현)

  • Kim, Tae Hyun;Yang, Oh
    • Journal of the Semiconductor & Display Technology
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    • v.18 no.4
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    • pp.81-86
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    • 2019
  • According to the needs of many users, motor pumps have been steadily developed and widely used in many industries where fluids are used. Motor pumps are used in a variety of environments, degrading quality and performance. It is becoming important to monitor the condition of motor pumps in order to maintain system performance and increase efficiency. This paper presents the method for effectively monitoring the condition of motor pumps. The designed MMI controller receives the collected data through data logging and output and controls the motor pump with touch screen. Implementing a Wi-Fi monitoring system and SCADA monitoring system based on Ethernet and RS485, user can monitor even if the user is far from the MMI controller without time and space limitation. In addition, by implementing a voice output system, the user can immediately recognize the situation through the sound. Therefore, through the proposed method, multi-monitoring system solves the cause of breakdowns and degradation of motor-pump and gives the possibility of commercialization by providing the convenience of maintenance to users.

Understanding the constraint induced movement and Self-efficacy in Stroke Patients (뇌졸중 환자의 건측억제유도와 자기효능에 대한 이해)

  • Shin, Hyung-Soo;Kim, Chung-Sun
    • PNF and Movement
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    • v.3 no.1
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    • pp.35-45
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    • 2005
  • Objectives : The purpose of this study was to understanding the constraint induced movement and Self-efficacy with arm training on upper motor function in Stroke Patients. Methods : Stroke, the leading cause of functional disability, causes a variety of impairments that compromise quality of life. Upper limb hemiparesis, a commonly seen impairment, is particularly problematic given its impact on activities of daily living. Because stroke was a disease to correspond to the first during domestic cause of death, and was accompanied by a lot of side aftereffects after a survival, stroke rehabilitation bought a patient and a family and a physical therapist, and it was main concern of. Results : Looks into upper extremity excrise of a subacute stroke patient estranged a acute convalescence later by a rehabilitation treatment in this consideration, and evaluates an effect to wind up constraint induced movement for an early treatment of stroke and Self efficacy, and help is one to an early rehabilitation of an stroke patient. Conclusions : Overuse sound tends after the stroke occurrence in the early stage in order to recompense for stroke, and at the time of a new aspect called learned nonuse syndrome by a movement of a paralysis part dusting off wealth with this step thing later. Constraint induced movement using self efficacy could be an effective for improving function of stroke.

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Mapping of Quantitative Trait Loci for Yield and Grade Related Traits in Peanut (Arachis hypogaea L.) Using High-Resolution SNP Markers

  • Liang, Yuya;Baring, Michael R.;Septiningsih, Endang M.
    • Plant Breeding and Biotechnology
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    • v.6 no.4
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    • pp.454-462
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    • 2018
  • Yield and grade are the key factors that affect production value of peanut. The objective of this study was to identify QTLs for pod yield, hundred-seed weight, and total sound mature kernel (TSMK). A total of 90 recombinant inbred lines, derived from Tamrun OL07 and a breeding line Tx964117, were used as a mapping population and planted in Brownfield and Stephenville, Texas. A genetic map was developed using 1,211 SNP markers based on double digest restriction-site associated DNA sequencing (ddRAD-seq). A total of 10 QTLs were identified above the permutation threshold, three for yield, three for hundred-seed weight and four for TSMK, with LOD score values of 3.7 - 6.9 and phenotypic variance explained of 12.2% - 35.9%. Among those, there were several QTLs that were detected in more than one field experiment. The commonly detected QTLs in this study may be used as potential targets for future breeding program to incorporate yield and grade related traits through molecular breeding.

Flammability and Multi-objective Performance of Building Façades: Towards Optimum Design

  • Bonner, Matthew;Rein, Guillermo
    • International Journal of High-Rise Buildings
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    • v.7 no.4
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    • pp.363-374
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    • 2018
  • The façade is an important, complex, and costly part of a building, performing multiple objectives of value to the occupants, like protecting from wind, rain, sunlight, heat, cold, and sound. But the frequency of façade fires in large buildings is alarming, and has multiplied by seven times worldwide over the last three decades, to a current rate of 4.8 fires per year. High-performing polymer based materials allow for a significant improvement across several objectives of a facade (e.g., thermal insulation, weight, and construction time) thereby increasing the quality of a building. However, all polymers are flammable to some degree. If this safety problem is to be tackled effectively, then it is essential to understand how different materials, and the façade as a whole, perform in the event of a fire. This paper discusses the drivers for flammability in facades, the interaction of facade materials, and current gaps in knowledge. In doing so, it aims to provide an introduction to the field of façade fires, and to show that because of the drive for thermal efficiency and sustainability, façade systems have become more complex over time, and they have also become more flammable. We discuss the importance of quantifying the flammability of different façade systems, but highlight that it is currently impossible to do so, which hinders research progress. We finish by putting forward an integral framework of design that uses multi-objective optimization to ensure that flammability is minimized while considering other objectives, such as maximizing thermal performance or minimizing weight.

Altitudinal Distribution Aspect of Benthic Macroinvertebrates in a Mountain Stream of Seoraksan (설악산 계류의 고도별 저서성 대형무척추동물의 분포특성)

  • Son, Se-Hwan;Kim, Jin young;Jo, Jae Ick;Kong, Dongsoo
    • Journal of Korean Society on Water Environment
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    • v.27 no.5
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    • pp.680-688
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    • 2011
  • This study was performed to find out the distribution aspect of benthic macroinvertebrates according to altitude in a mountain stream (a main stream: Buk stream, a tributary: Hangye stream) of Seoraksan. The survey was conducted from August to November in 2010. All survey sites were very sound because the mountain was being maintained as a protection area of the national park. Water quality and the composition of substrata were similar in all sites. Benthic macroinvertebrates of 3 phyla, 4 classes, 9 orders and 84 species occurred in the stream. Along with the decline of altitude, shredders of the functional feeding groups (FFGs) decreased, while collector filterers increased. In particular, collector filterers increased sharply at the altitude of 600 ~ 500 m (S.E.L.). Benthic macroinvertebrates showed low similarity between the uppermost site and the lower sites. Altitude appeared to be a significant factor that influence the structure and distribution of benthic macroinvertebrate community.

A Development of the Preschool Teacher Play Support Scale Based on the Play Practice Resources for Teachers of the 2019 Revised Nuri Curriculum (2019 개정 누리과정 놀이실행자료에 기초한 유아교사용 놀이지원 척도 개발)

  • Sung, Anna;Kim, Yeon Ha;Lee, Jiseon
    • Korean Journal of Childcare and Education
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    • v.18 no.2
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    • pp.19-38
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    • 2022
  • Objective: The goal of this study is to develop an instrument for measuring the quality of teacher support for children's play (age 3-5) based on the Play Practice Resources for Teachers presented in the 2019 revised Nuri Curriculum. Methods: The subjects of this study were 333 early childhood educators. Exploratory and confirmatory factor analysis, as well as correlation analysis were all performed to confirm construct validity and concurrent validity. The reliability of each factor was verified using Cronbach's alpha. Results: The Preschool Teacher Play Support Scale (PTPSS) was finalized with 25 items, which included the following four sub-factors: interaction, play materials, play space, and play safety. The concurrent validity was also confirmed through significant correlations between the existing measures such as the Teacher Self-Efficacy Scale, the Teaching Efficacy Scale for Play, and the Teacher-Toddler Interaction Scale. The reliability of each factor was also desirable. Conclusion/Implications: The PTPSS was verified as a sound measure quantifying the play support behavior of teachers who respect the autonomy and initiative of young children which is being pursued by the 2019 revised Nuri Curriculum.

Acoustic Emission and Burr Comparison of Circular Sawing and Milling in Fiber Reinforced Plastic Cutting (원형 톱과 엔드밀의 복합재료 절단 음향과 버 비교연구)

  • Joo, Chang-Min;Baek, Jong-Hyun;Kim, Su-Jin;Lee, Gun-Myung
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.21 no.7
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    • pp.98-104
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    • 2022
  • Circular sawing and milling are general machining processes used for routing fiber-reinforced plastics (FRP). In this study, the productivity and cutting quality of a circular saw and flat endmill were compared. As a result, the productivity of the circular saw was approximately ten times higher than that of the endmill for the same tool life, and the burr size of the circular saw was 14 times smaller than that of the flat-end mill. The spectrogram analysis of the cutting sound also showed that the acoustic emission of the circular saw was more uniform than that of the flat end mill. Circular sawing is thus a more suitable process for the straight cutting of pultrusion FRP than a flat endmill.

Implementing Rule-based Healthcare Edits

  • Abdullah, Umair;Shaheen, Muhammad;Ujager, Farhan Sabir
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.16 no.1
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    • pp.116-132
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    • 2022
  • Automated medical claims processing and billing is a popular application domain of information technology. Managing medical related data is a tedious job for healthcare professionals, which distracts them from their main job of healthcare. The technology used in data management has a sound impact on the quality of healthcare data. Most of Information Technology (IT) organizations use conventional software development technology for the implementation of healthcare systems. The objective of this experimental study is to devise a mechanism for use of rule-based expert systems in medical related edits and compare it with the conventional software development technology. A sample of 100 medical edits is selected as a dataset to be tested for implementation using both technologies. Besides empirical analysis, paired t-test is also used to validate the statistical significance of the difference between the two techniques. The conventional software development technology took 254.5 working hours, while rule-based technology took 81 hours to process these edits. Rule-based technology outperformed the conventional systems by increasing the confidence value to 95% and reliability measure to 0.462 (which is < 0.5) which is three times more efficient than conventional software development technology.