• Title/Summary/Keyword: Loss of head

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A case of a Spindle cell/pleomorphic lipoma in the lateral neck (측경부에 발생한 방추세포 / 다형성 지방종1예)

  • Kim, Young Yoon;Yoon, Sung Ho;Park, Jong Min;Lee, Dong Hoon
    • Korean Journal of Head & Neck Oncology
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    • v.34 no.1
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    • pp.41-43
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    • 2018
  • The Spindle cell lipoma is a slow-growing benign tumor seen generally in the shoulders, upper back, and back of the neck of male. The Pleomorphic (giant-cell) lipoma is a benign tumor of adipose tissue with atypical histological features. It is mainly seen in the same lesion as the Spindle cell lipoma. The Pleomorphic lipoma is cytogenetically similar to spindle cell lipoma with a consistent loss of chromosome 16q material. For this reason, these two entities are regarded as a similar spectrum in the adipose tumors. Herein, we present a 53-year old man with Spindle cell/pleomorphic lipoma in the lateral neck. Physical and radiologic examinations of the Spindle cell/pleomorphic lipoma in the lateral neck are not specific and preoperative diagnosis is usually difficult. Therefore, clinicians should consider the possibility that Spindle cell/pleomorphic lipoma may occur in the lateral neck mimicking the other more frequently observed lesions.

Hydraulic Computation and Stress Analysis of Box Culvert (암거의 수리 및 응력계산)

  • 함준호
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.14 no.1
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    • pp.2557-2569
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    • 1972
  • Hydraulic computations to determine the elevation of canal bottom and mater surface for box type concrete culverts are discussed. Velocity and cross sectional area of flow are computed from Manning's formula. Aad then head loss and velocity head are considered to determine the elevation of bottom and water surface. For stress analysis, 13.5 ton live load and earth pressure are considered. Also longitudinal stress of box culverts is checked.

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Trust Predicated Routing Framework with Optimized Cluster Head Selection using Cuckoo Search Algorithm for MANET

  • Sekhar, J. Chandra;Prasad, Ramineni Sivarama
    • IEIE Transactions on Smart Processing and Computing
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    • v.4 no.2
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    • pp.115-125
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    • 2015
  • This paper presents a Cuckoo search algorithm to secure adversaries misdirecting multi-hop routing in Mobile ad hoc networks (MANETs) using a robust Trust Predicated Routing Framework with an optimized cluster head selection. The clustering technique designed in this framework leads to efficient routing in MANETs. The heavy work load in the node causes an energy drop in cluster head, which leads to re-clustering of the group, and another cluster head is selected to avoid packet loss during data transmission. The problem in the re-clustering process is that the overall efficiency of the routing process is reduced and the processing time is increased. A Cuckoo search based optimization algorithm is proposed to solve the problem of re-clustering by selecting the secondary cluster head within the initially formed cluster group and eliminating the reclustering process. The proposed framework enables a node to select a reliable and secure route for MANET and the performance can be evaluated by comparing the simulated results with the AODV routing protocol, which shows that the performance of the proposed routing protocol are improved significantly.

Speech Perception and Gap Detection Performance of Single-Sided Deafness under Noisy Conditions

  • Kwak, Chanbeom;Kim, Saea;Lee, Jihyeon;Seo, Youngjoon;Kong, Taehoon;Han, Woojae
    • Journal of Audiology & Otology
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    • v.23 no.4
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    • pp.197-203
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    • 2019
  • Background and Objectives: Many studies have reported no benefit of sound localization, but improved speech understanding in noise after treating patients with single-sided deafness (SSD). Furthermore, their performances provided a large individual difference. The present study aimed to measure the ability of speech perception and gap detection in noise for the SSD patients to better understand their hearing nature. Subjects and Methods: Nine SSD patients with different onset and period of hearing deprivation and 20 young adults with normal hearing and simulated conductive hearing loss as the control groups conducted speech perception in noise (SPIN) and Gap-In-Noise (GIN) tests. The SPIN test asked how many presented sentences were understood at the +5 and -5 dB signal-to-noise ratio. The GIN test was asked to find the shortest gap in white noise with different lengths in the gap. Results: Compared to the groups with normal hearing and simulated instant hearing loss, the SSD group showed much poor performance in both SPIN and GIN tests while supporting central auditory plasticity of the SSD patients. Rather than a longer period of deafness, the large individual variance indicated that the congenital SSD patients showed better performance than the acquired SSD patients in two measurements. Conclusions: The results suggested that comprehensive assessments should be implemented before any treatment of the SSD patient considering their onset time and etiology, although these findings need to be generalized with a large sample size.

Speech Perception and Gap Detection Performance of Single-Sided Deafness under Noisy Conditions

  • Kwak, Chanbeom;Kim, Saea;Lee, Jihyeon;Seo, Youngjoon;Kong, Taehoon;Han, Woojae
    • Korean Journal of Audiology
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    • v.23 no.4
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    • pp.197-203
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    • 2019
  • Background and Objectives: Many studies have reported no benefit of sound localization, but improved speech understanding in noise after treating patients with single-sided deafness (SSD). Furthermore, their performances provided a large individual difference. The present study aimed to measure the ability of speech perception and gap detection in noise for the SSD patients to better understand their hearing nature. Subjects and Methods: Nine SSD patients with different onset and period of hearing deprivation and 20 young adults with normal hearing and simulated conductive hearing loss as the control groups conducted speech perception in noise (SPIN) and Gap-In-Noise (GIN) tests. The SPIN test asked how many presented sentences were understood at the +5 and -5 dB signal-to-noise ratio. The GIN test was asked to find the shortest gap in white noise with different lengths in the gap. Results: Compared to the groups with normal hearing and simulated instant hearing loss, the SSD group showed much poor performance in both SPIN and GIN tests while supporting central auditory plasticity of the SSD patients. Rather than a longer period of deafness, the large individual variance indicated that the congenital SSD patients showed better performance than the acquired SSD patients in two measurements. Conclusions: The results suggested that comprehensive assessments should be implemented before any treatment of the SSD patient considering their onset time and etiology, although these findings need to be generalized with a large sample size.

Analysis of control rod driving mechanism nozzle rupture with loss of safety injection at the ATLAS experimental facility using MARS-KS and TRACE

  • Hyunjoon Jeong;Taewan Kim
    • Nuclear Engineering and Technology
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    • v.56 no.6
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    • pp.2002-2010
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    • 2024
  • Korea Atomic Energy Research Institute (KAERI) has operated an integral effect test facility, the Advanced Thermal-Hydraulic Test Loop for Accident Simulation (ATLAS), with reference to the APR1400 (Advanced Power Reactor 1400) for tests for transient and design basis accidents simulation. A test for a loss of coolant accident (LOCA) at the top of the reactor pressure vessel (RPV) had been conducted at ATLAS to address the impact of the loss of safety injections (LSI) and to evaluate accident management (AM) actions during the postulated accident. The experimental data has been utilized to validate system analysis codes within a framework of the domestic standard problem program organized by KAERI in collaboration with Korea Institute of Nuclear Safety. In this study, the test has been analyzed by using thermal-hydraulic system analysis codes, MARS-KS 1.5 and TRACE 5.0 Patch 6, and a comparative analysis with experimental and calculation results has been performed. The main objective of this study is the investigation of the thermal-hydraulic phenomena during a small break LOCA at the RPV upper head with the LSI as well as the predictability of the system analysis codes after the AM actions during the test. The results from both codes reveal that overall physical behaviors during the accident are predicted by the codes, appropriately, including the excursion of the peak cladding temperature because of the LSI. It is also confirmed that the core integrity is maintained with the proposed AM action. Considering the break location, a sensitivity analysis for the nodalization of the upper head has been conducted. The sensitivity analysis indicates that the nodalization gave a significant impact on the analysis result. The result emphasizes the importance of the nodalization which should be performed with a consideration of the physical phenomena occurs during the transient.

A Study on Hydraulic Calculation Procedure of Fire Sprinkler System Design (스프링클러설비 설계의 수리계산 절차에 대한 연구)

  • Jeong, Keesin
    • Fire Science and Engineering
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    • v.32 no.1
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    • pp.24-32
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    • 2018
  • There are two kinds of method on hydraulic calculation of fire sprinkler system design. The one is using the computational program and the other is designer calculate system for oneself. In case of using the computational program, putting the input data in, the program calculate the friction loss, water flow, total height and so forth. If program user or designer doesn't know the basic idea and procedure of hydraulic calculation. Then, the outputs are different from each other. This paper suggests the hydraulic calculation procedure in design area as follow. Equivalent lengths of tees on the branch are selected base on the same pipe diameter which the tees are established, although the diameter of tee outlet is different. Even though there is a different friction loss of head from the other head, the pressure from the hydraulic end is bigger than a head loss, discharge flow is calculated by pressure from the hydraulic end.

Characteristics of Depth Filtration for Various Filter-Bed Configurations (심층여과지의 여층구성에 따른 여과특성 비교)

  • An, Jong-Ho;Yun, Jae-Heung
    • Journal of Korea Water Resources Association
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    • v.34 no.5
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    • pp.459-472
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    • 2001
  • The objective of this study is to evaluate the filtration efficiency of deep-bed filters by comparing to single and dual media filters. Pilot-plant tests using four-filter columns were conducted for the comparison of head loss development and filtered water quality. The dual-media filter showed greater initial head loss, but less rate of head-loss development than those of the coarse-sand-0deep-bed filters. For 180 m/day of filtration rate, the dual-media filter produces larger unit production rate by 30-40%, and the turbidities of filtered water were below 0.1 NTU. The initial breakthrough could be effectively controlled by the dual-media filter rather than coarse-sand-deep-bed filters.

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A Personal Sound Amplification Product Compared to a Basic Hearing Aid for Speech Intelligibility in Adults with Mild-to-Moderate Sensorineural Hearing Loss

  • Choi, Ji Eun;Kim, Jinryoul;Yoon, Sung Hoon;Hong, Sung Hwa;Moon, Il Joon
    • Journal of Audiology & Otology
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    • v.24 no.2
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    • pp.91-98
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    • 2020
  • Background and Objectives: This study aimed to compare functional hearing with the use of a personal sound amplification product (PSAP) or a basic hearing aid (HA) among sensorineural hearing impaired listeners. Subjects and Methods: Nineteen participants with mild-to-moderate sensorineural hearing loss (SNHL) (26-55 dB HL; pure-tone average, 0.5-4 kHz) were prospectively included. No participants had prior experience with HAs or PSAPs. Audiograms, speech intelligibility in both quiet and noisy environments, speech quality, and preference were assessed in three different listening conditions: unaided, with the HA, and with the PSAP. Results: The use of PSAP was associated with significant improvement in pure-tone thresholds at 1, 2, and 4 kHz compared to the unaided condition (all p<0.01). In the quiet environment, speech intelligibility was significantly improved after wearing a PSAP compared to the unaided condition (p<0.001), and this improvement was better than the result obtained with the HA. The PSAP also demonstrated similar improvement in the most comfortable levels compared to those obtained with the HA (p<0.05). However, there was no significant improvement of speech intelligibility in a noisy environment when wearing the PSAP (p=0.160). There was no significant difference in the reported speech quality produced by either device or in participant preference for the PSAP or HA. Conclusions: The current result suggests that PSAPs provide considerable benefits to speech intelligibility in a quiet environment and can be a good alternative to compensate for mild-to-moderate SNHL.

A Personal Sound Amplification Product Compared to a Basic Hearing Aid for Speech Intelligibility in Adults with Mild-to-Moderate Sensorineural Hearing Loss

  • Choi, Ji Eun;Kim, Jinryoul;Yoon, Sung Hoon;Hong, Sung Hwa;Moon, Il Joon
    • Korean Journal of Audiology
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    • v.24 no.2
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    • pp.91-98
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    • 2020
  • Background and Objectives: This study aimed to compare functional hearing with the use of a personal sound amplification product (PSAP) or a basic hearing aid (HA) among sensorineural hearing impaired listeners. Subjects and Methods: Nineteen participants with mild-to-moderate sensorineural hearing loss (SNHL) (26-55 dB HL; pure-tone average, 0.5-4 kHz) were prospectively included. No participants had prior experience with HAs or PSAPs. Audiograms, speech intelligibility in both quiet and noisy environments, speech quality, and preference were assessed in three different listening conditions: unaided, with the HA, and with the PSAP. Results: The use of PSAP was associated with significant improvement in pure-tone thresholds at 1, 2, and 4 kHz compared to the unaided condition (all p<0.01). In the quiet environment, speech intelligibility was significantly improved after wearing a PSAP compared to the unaided condition (p<0.001), and this improvement was better than the result obtained with the HA. The PSAP also demonstrated similar improvement in the most comfortable levels compared to those obtained with the HA (p<0.05). However, there was no significant improvement of speech intelligibility in a noisy environment when wearing the PSAP (p=0.160). There was no significant difference in the reported speech quality produced by either device or in participant preference for the PSAP or HA. Conclusions: The current result suggests that PSAPs provide considerable benefits to speech intelligibility in a quiet environment and can be a good alternative to compensate for mild-to-moderate SNHL.