• Korean Journal of Plant Resources
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• v.29 no.6
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• pp.670-678
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• 2016

We compared the germination rate of dehisced ginseng (Panax ginseng) seeds that were dried under two different conditions, slowly at $15^{\circ}C$ [relative humidity (RH) 10-12%] and rapidly under a laminar airflow cabinet at $25^{\circ}C$ (RH 22-25%). The measurements showed that drying rate and seed moisture content (SMC) play important roles in storage ability and vigor. The seeds that were dried rapidly at $25^{\circ}C$ showed high GR compared with the seeds that were dried at $15^{\circ}C$ after 6 and 12 months of storage at $-80^{\circ}C$ irrespective of MC. Seeds dried slowly at $15^{\circ}C$ with MC higher than 7.0% showed high GR maintenance after storage at $-18^{\circ}C$ and at $4^{\circ}C$ in comparison with rapidly dried seeds. However, the GR of the slowly desiccated seeds decreased as mean SMC was reduced to less than 5.0%, whereas the rapidly dried seeds were distinguished by significantly high GR irrespective of the storage conditions. The ginseng seeds desiccated under different conditions showed differences in storage performance. Seeds with 7-9% MC that were dried slowly at $15^{\circ}C$ for 5-7 days showed high GR after $4^{\circ}C$ and $-18^{\circ}C$ storage; however, longer periods of desiccation decreased the germination level remarkably compared with that of rapidly dried seeds.

• Speech Sciences
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• v.10 no.2
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• pp.111-128
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• 2003

Aerodynamic study is valuable information about the vocal efficiency in translating airflow to acoustic signal. The purpose of this study was to investigate the differences between trained singers and untrained controls under different two pitch by simultaneous using the airway interruption method and electroglottography (EGG). Under singing a Korean lied 'Gene', 20 (Male 10, Female 10) trained singers were studied on two one-octave different tone. Mean flow rate (MFR) , subglottic pressure (Psub) and intensity were measured with aerodynamic test using the Phonatory function analyzer (Nagashima Ltd. Model PS 77H, Tokyo, Japan). Closed quotients (Qx), jitter and shimmer were also investigated by electroglottography using Lx speech studio (Laryngograph Ltd, London, UK). These data were compared with those of normal controls. MFR and Psub were increased on high pitch tone in all subject groups. Statistically significant increasing of Qx and intensity were observed in male trained singers on high pitch tone (Qx;p = .025, intensity;p < .001). Beacasue of increasing of Qx and intensity, vocal efficiency was also significantly increased in male singers (p < .001). The trained singers' phonation was more efficient than untrained singers. The result means that the trained singers can increase the loudness with little changing of mean flow rate, subglottic pressure but more increasing of glottic closed quotients.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.5
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• pp.482-489
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• 2004

The purpose of this study is to reevaluate the performance of Hanji as a architectural material. Recent studies report that one of the causes of the Sick-HouseㆍSick-Building Syndrome is due to the contaminants from interior materials and the lack of ventilation. In this study, the properties of Hanji are investigated. The major focuses of this research are (1) how efficient the Hanji is for ventilation of the house and (2) whether the usage of Hanji brings required ventilation volume to the house. According to the test results, differential pressure in the air and the amount of ventilation showed linear relationship. Test results differ from various kinds of Hanji. Since houses usually have double window system, Hanji can be used to the windows system, especially for inner part of double window system. It is suggested that the combination of Hanji windows for the inner part and glass windows for outer part is very effective, and offers a solution to improvement of indoor air quality and the lack of ventilation with passive ventilation that has less energy consumption.

• Phonetics and Speech Sciences
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• v.5 no.1
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• pp.19-26
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• 2013

The aerodynamic characteristics (subglottal pressure (Ps) and mean airflow rate (MFR)), fundamental frequency (Fo), intensity (I), vocal efficiency (VE), and closed quotient (CQ) were compared during a sustained vowel /o/ sound under three conditions: in a comfortable loudness and pitch level (condition 1), in a maximum loudness level with a fixed pitch (condition 2), and in a maximum loudness level without a fixed pitch (condition 3). Also, multiple regression analyses were done to measure the aerodynamic characteristics affect on the VE and the CQ in each condition. The results showed the Fo, Ps, MFR, VE, and CQ increased as I increased with and without fixed pitch. Most notably, VE in condition 3 was the highest of all the conditions, but CQ was not very high. By the results of multiple regression analysis, VE was significantly affected by I and Ps in all conditions; Fo was the other main key for affecting VE in high pitch. However, none of the aerodynamic characteristics significantly affected CQ. As I increases, Fo should be increased by increasing Ps and VE. Therefore, researchers should consider and specify an a priori to Fo, Ps, and I when measuring VE to examine the complex and delicate vocal mechanism.

• Journal of Animal Environmental Science
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• v.12 no.2
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• pp.85-94
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• 2006

The effects of turning frequency of in-vessel composting on ammonia emissions during composting of separated solids from swine slurry/sawdust mixtures and performance of biofiltration using the chicken manure compost were investigated. Separated solids from swine manure amended with sawdust was composted in a 226 L laboratory-scale in-vessel reactors under various turning frequency and continuous airflow (0.6 L/min.kg.dm) for three weeks. Three laboratory-scale manure compost biofilters were built to treat effluent gas from the composting of separated solid from swine manure amened with sawdust process. These experiments were continued over a period of three weeks. The composting of separated solid swine manure amended with sawdust and manure compost biofiltration system were evaluated to determine the turning frequency type that would be adequate for the rate of decomposition and compost odour reduction. The compost odour cleaning was measured based on ammonia gas concentration before and after passing through the manure compost biofilter. The average ammonia odor reduction in the manure compost biofilter was 96.9 % at R1 (no turning), 99.4 % at R2(once a day turning) and 89.0 % at R3(twice a day turning), respectively. The efficiency of ammonia reduction was mainly influenced by the turning frequency.

• KIEAE Journal
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• v.16 no.3
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• pp.95-101
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• 2016

Purpose: Recently, high-rise buildings are popular in korea due to high rate of land usage and cost performance in urban area. However, high-rise building causes several problems such as safety issues, cooling/heating load, stack effect, disaster prevention etc. The stack effect is one of the representative problems. Even though there are many researches on stack effect, there are few studies on design guideline considering local condition. Method: This study focuses on the change of pressure distribution according to the design factors which affects the airflow in high-rise residential buildings by simulation analysis. In this study, city, building floor, stairwell door leakage area, elevator door leakage area and changes of layout were considered ad the design factor. Result: The simulation results indicate that building height and ambient air temperature are significant design factor for stack effect.

• Phonetics and Speech Sciences
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• v.5 no.4
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• pp.17-24
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• 2013

This study is aimed at finding out different types of speech characteristics categorized based on voice rehabilitation techniques used on twenty-six patients (all-male) with total or partial laryngectomees. The speech intelligibility of standard esophageal (SE), tracheoesophageal speech (TE), and electriclarynx (EL) was measured by using the CSL and eleven listeners were instructed to rate the speech on a 5-point scale. The vowel space parameters such as vowel space, VAI, FCR, and F2 ratio were measured by averaging 5 repeats of each vowel (/a/, /e/, /i/, /u/) and the results were put into the parameter formula. The results showed significant statistical differences in speech intelligibility and vowel space between SE and TE. The speech intelligibility and vowel space of TE were higher than those of SE or EL and there was a high correlation between speech intelligibility and some parameters (vowel space, VAI, F2 ratio). The results also showed that TE's speech characteristics were most similar to normal groups comparing with SE and EL, but still very deviant in laryngeal speech. This was due to insufficient airflow intake into the esophagus when producing sounds, and because articulation movement was carried out differently among groups. Therefore, these findings will contribute to establishing a baseline related to speech characteristics in voice rehabilitation for patients with alaryngeal speech.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.13 no.2
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• pp.151-154
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• 2002

Background and Objectives : The pitch range of the human voice is variable, extending from chest register to falsetto register. Although numerous studies have investigated after laryngeal mechanism description of falsetto tone, systematic and objective studies were lack. The purpose of this study was to systematically analyze and compare modal with falsetto voice. Materials and Methods : Seven adult baritones were selected from a larger population of volunteers at choir. Simultaneous measurements of acoustic, electroglottographic and aerodynamic study were made during /e/ sustained in two vocal registers, lowest modal and highest falsetto. Statistical analysis was performed using Wilkoxson signed rankes test. Results : In the acoustic analysis, shimmer was increased in flasetto voice(p<0.05). In the electroglottographic analysis, closed quotient(CQ), speed quotient(SQ) at the modal voice were higher than at the falsetto voice(p<0.05). In the aerodynamic analysis, and airflow rate(MFR) of falsetto voice was higher than modal voice(p<0.05). Conclusions : In the results of the study indicate that, falsetto register ineffective, inefficient, generally unpleasant because it was produced by incomplete clousure of true vocal cord. We anticipated that further study with large samples can provide an objective criteria for status and classification of singer's modal and falsetto voice.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.9 no.3
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• pp.410-425
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• 1997

Buildings are mostly under part load conditions causing an inefficient system operation in terms of energy consumption. It is critical to operate building air-conditioning system with a scientific or optimal manner which minimizes energy consumption and maintains thermal comfort by matching building sensible and latent loads. Little research has been performed in developing general methodologies for the optimal operation of air-conditioning system. Based on this research motivation, system simulation program was developed by adopting various equipment operating strategies which are energy efficient especially for humidity control in summer. A numerical optimization technique was utilized to search optimal solution for multi-independent variables and then linked to the developed system simulation model within a mam program. The main goal of the study is to provide a systematic framework and guideline for the optimal operation of air-conditioning system focusing on air-side. For given cooling loads and ambient outdoor conditions the optimal operating strategies of a commercial building are determined by minimizing a constrained objective function by a nonlinear programming technique. Desired space setpoint conditions were found through evaluating the trade-offs between comfort and system power consumption. The results show that supply airflow rate and compressor fraction play main roles in the optimization process. It was found that variable setpoint optimization technique could produce lower indoor humidity level demanding less power consumption which will be benefits for building applications of humidity problem.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.745-750
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• 2009

In Korea, since the implementation of the GMO Law, the intrest of biosafety level 3(BL3) lab. is increasing. In this study, using CONTAM which is applying multizone modelling, the multizone simulation for design verification of BL3 lab. was performed. In BL3 lab., because required air change rate is greater than general estimated air-conditioning load and it is difficult to maintain room pressure difference efficiently, to maintain pressure difference between laboratory rooms is important through sealing condition of doors and proper airflow control of laboratory rooms. In this study, about BL3 lab.(M. tuberculosis research lab.), the multizone simulation for four kind of biohazard scenarios was performed in the case of unexpected spread of contaminants in the laboratory room, anteroom, corridor and inside of BSC. Multizone simulation results show that these approach methods are used as a tool for the design and verification of BL3 lab.