• Title/Summary/Keyword: Standing time

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Comparison of Simple Random Sampling and Two-stage P.P.S. Sampling Methods for Timber Volume Estimation (임목재적(林木材積) 산정(算定)을 위(爲)한 Simple Random Sampling과 Two-stage P.P.S. Sampling 방법(方法)의 비교(比較))

  • Kim, Je Su;Horning, Ned
    • Journal of Korean Society of Forest Science
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    • v.65 no.1
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    • pp.68-73
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    • 1984
  • The purpose of this paper was to figure out the efficiencies of two sampling techniques, a simple random sampling and a two-stage P.P.S. (probability proportional to size) sampling, in estimating the volume of the mature coniferous stands near Salzburg, Austria. With black-and-white infrared photographs at a scale 1:10,000, the following four classes were considered; non-forest, young stands less than 40 years, mature beech and mature coniferous stands. After the classification, a field survey was carried out using a relascope with a BAF (basal area factor) 4. For the simple random sampling, 99 points were sampled, while for the P.P.S. sampling, 75 points were sampled in the mature coniferous stands. The following results were obtained. 1) The mean standing coniferous volume estimate was $422.0m^3/ha$ for the simple random sampling and $433.5m^3/ha$ for the P.P.S. sampling method. However, the difference was not statistically significant. 2) The required number of sampling points for a 5% sampling error were 170 for the two stage P.P.S. sampling, but 237 for the simple random sampling. 3) The two stage P.P.S. method reduced field survey time by 17% as compared to the simple random sampling.

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Experimental and CFD Study on the Exhaust Efficiency of a Smoke Control Fan in Blind Entry Development Sites (맹갱도 굴진 작업공간내 방재팬의 화재연 배기효율에 관한 현장실험 및 CFD 연구)

  • Nguyen, Vanduc;Kim, Dooyoung;Hur, Wonho;Lee, Changwoo
    • Tunnel and Underground Space
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    • v.28 no.1
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    • pp.38-58
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    • 2018
  • The ventilation system plays a crucial role in underground mine safety. The main objective of the ventilation system is to supply sufficient air to dilute the contaminated air at working places and consequently provide tenable environment during the normal operation, while it also should be capable of controlling the fire propagation and facilitate rescue conditions in case of fire in mines. In this study, a smoke control fan was developed for the auxiliary ventilation as well as the fire smoke exhaust. It works as a free-standing auxiliary fan without tubing to dilute or exhaust the contaminated air from the working places. At the same time, it can be employed to extract the fire smoke. This paper aims to examine the smoke control efficiency of the fan when combined with the current ventilation system in mines. A series of the site experiments and numerical simulations were made to evaluate the fan performance in blind entry development sites. The tracer gas method with SF6 was applied to investigate the contaminant behavior at the study sites. The results of the site study at a large-opening limestone mine were compared with the CFD analysis results with respect to the airflow pattern and the gas concentration. This study shows that in blind development entry, the most polluted and risky place, the smoke fan can exhaust toxic gases or fire smoke effectively if it is properly combined with an additional common auxiliary fan. The venturi effect for smoke exhaust from the blind entry was also observed by the numerical analysis. The overall smoke control efficiency was found to be dependent on the fan location and operating method.

Numerical Simulation of Regular Wave Transformation due to Wave-induced Current over a Submerged Elliptic Shoal (수중타원형 천퇴를 통과하는 규칙파의 파랑쇄파류에 의한 변형)

  • Choi, Jun-Woo;Baek, Un-Il;Yoon, Sung-Bum
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.19 no.6
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    • pp.557-564
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    • 2007
  • The effect of wave and current interactions on regular wave transformation over a submerged elliptic shoal is investigated based on numerical simulations of the Vincent and Briggs experiment [Vincent, C.L., Briggs, M.J., 1989. Refraction-diffraction of irregular waves over a mound. Journal of Waterway, Port, Coastal and Ocean Engineering, 115(2), pp. 269-284]. The numerical simulations are conducted by constituting two numerical model systems: a combination of SWAN(a wave model) plus SHORECIRC(a current model) and a combination of REF/DIF 1(a wave model) plus SHORECIRC. A time dependent phase-resolving wave-current model, FUNWAVE, is also utilized to simulate the experiment. In the simulations, the breaking-induced currents defocus waves behind the shoal and bring on a wave shadow zone that shows relatively low wave height distributions. The computed results of the two model systems agree better with the measurements than the computed results obtained by neglecting wave-current interaction do. However, it is found that the radiation stresses for standing waves are misevaluated in the wave models. In addition, the results of FUNWAVE show very good agreement with the measurements. The agreement indicates that it is necessary to take into account the effect of breaking-induced current on wave refraction when wave-breaking occurs over a submerged shoal.

Activities of a Home Hospice Organization (가정호스피스기관의 활동에 관한 연구)

  • Kim, Jung-Hee;Choi, Young-Soon
    • Journal of Hospice and Palliative Care
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    • v.3 no.1
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    • pp.28-38
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    • 2000
  • Purpose : This study examined characteristics of, problems of and services provided to hospice recipients and their family members at a home hospice organization. Methods : The subjects were 113 people who were discharged from one free-standing home hospice organization between November, 1994 and lune, 1999. Since the opening of the organization in November of 1994, it has provided hospice services at patients' homes with no charge. Data were collected from those subjects' records. Results : The average age of the subjects was 57.1 years; those aged 60 and over were 54%. Spouse was the most frequent(50.9%) primary caregiver followed by daughter-in-law and daughter. All the subjects were diagnosed as having cancer. Of those 41 subjects who did not know their terminal stage in the beginning, 31 subjects came to know their states. Of the subjects, 72.7% were referred from their physicians. On the average, the service duration and the number of home visits were 6.8 weeks and 7.2 times, respectively. Pain was the most prevalent problem of the subjects(89.4%). Medication management was the most frequently provided service followed by psychological supports. The reasons for discharge were death(88.5%) and refusal(8%). Home was the most frequent place of death(60%). Conclusion Home hospice service providers should be trained particularly in working with elders and in managing cancer pain. People need to be referred at an appropriate time for achieving goals of hospice. Community recognition of hospice services needs to be promoted.

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A numerical study on the unsteady agglomeration behavior of algae in the ultrasonic wave pressure field (초음파 압력장에서 미세조류 응집 거동에 관한 비정상상태 수치해석 연구)

  • Ha, Ji Soo;Shim, Sung Hun;Jung, Sang Hyun
    • Journal of Energy Engineering
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    • v.26 no.4
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    • pp.67-73
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    • 2017
  • For the bio-fuel conversion of algae, several processes are needed including cultivating, agglomeration, extracting and conversion to the bio-fuel. The production cost for each process makes the total production cost of algae bio-fuel conversion. The production cost of algae bio-fuel has still higher than that of the other commercial bio-fuel. The reduction of production cost for each process enables the competitive price as a bio-fuel. It is difficult to separate the algae from water because of the similar magnitude of density each other. The agglomeration and extracting of algae using ultrasonic wave is rare effect of environmental hazard and also it is appropriate technology for the next generation energy resources. The present research is investigated for the elucidation of algae behavior in the water with the ultrasonics wave. For this purpose, the unsteady computational fluid dynamic analysis has been conducted in the ultrasonic pressure field. The velocity, pressure and algae concentration changes with time have been analysed to clarify the mechanism of algae separation by ultrasonic wave.

Note on the New Record of Mitrula paludosa (Geoglossaceae) in Korea (콩나물버섯과 미기록종 Mitrula paludosa (습지등불버섯 : 신칭)의 보고)

  • Park, Yong-Woo;Koo, Chang-Duck;Hong, Dae-Eui;Kim, Tae-Heon
    • The Korean Journal of Mycology
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    • v.37 no.1
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    • pp.104-107
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    • 2009
  • Mitrula paludosa (Geoglossaccae, Helotiales, Ascomycetes) is reported about morphological and ecological characteristics for the first time in Korea. The mushroom fruited on rotten pine leaves or fine twigs in ditches with flowing or standing water in Sogri Mountain National Park from May to June. The apothecium of M. paludosa is 20 to 50 mm tall. The cap is bright yellow to orange, cylindrical to wrinkled ovoid and $5{\sim}10\;{\times}\;10{\sim}20$ mm. The stem is whitish and cylindrical distinctly set off from the cap. The ascospore is hyaline, smooth long elliptical fusoid with round ends and $13{\sim}17\;{\times}\;1.5{\sim}2.0{\mu}m$. The ascus is unitunicate, $90{\sim}110\;{\times}\;5{\sim}6{\mu}m$, and has eight spores biseriately lined to the inoperculate apex. Paraphyses are septate filiform, $95{\sim}120\;{\times}\;1.0{\sim}1.5{\mu}m$, $7{\sim}10{\mu}m$ longer than the asci.

Studies on the Volatile Aroma Components of Pleurotus ostreatus (느타리버섯의 향기(香氣) 성분(成分)에 관한 연구(硏究))

  • Hong, Jai-Sik;Lee, Ji-Yul;Kim, Young-Hoi;Kim, Myung-Kon;Jung, Gi-Tae;Lee, Keug-Ro
    • The Korean Journal of Mycology
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    • v.14 no.1
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    • pp.31-36
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    • 1986
  • The volatile aroma concentrates were isolated from Pleurotus ostreatus by simultaneous distillation-extraction and analyzed by gas chromatography and combined gas chromatography-mass spectrometry. The aroma concentrates obtained had a typical raw or slightly cooked mushroom-like odor, and the yield was 123 ppm. Of 27 components identified, the major components were 3-octanone, 3-octanol, 2-octenal, n-octanol and 2, 4-decadienal, including 1-octen-3-ol contributing 67.06% of the total volatiles, and the $C_8$ compounds comprised about 80% of the total volatiles. On the other hand, the $C_6$ and $C_8$ alcohols in mushroom increased gradually with increase of standing time after homogenation, while aldehydes, ketones, and linoleic acid decreased, and also $C_6$ and $C_8$ compounds were significantly increased when linoleic and linolenic acid were added in homogenates. It appears that most of volatile aroma components in Pleurotus ostreatus were probably produced enzymatically from unsaturated fatty acids containing cis, cis-1, 4-pentadiene moiety.

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The Qualitative Study on the Triggering Factors of Private Security Guards' Stress (민간경호원의 스트레스 유발요인에 관한 질적연구)

  • Kim, Jin-Hwan
    • Korean Security Journal
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    • no.15
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    • pp.89-105
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    • 2008
  • The aim of this study is to examine the primary causes of security guard's stress by conducting a survey of 50 guards engaging in security companies in Seoul and Gyeonggido. The following results are attained by an inductive content analysis of conviction interview data through in-depth interview of qualitative study method. 1. Factors of stress related to personal problems. The stress by personal problems is resulted from two factors. One is the physical strength inferiority, which leads to negative thoughts, dismay, mental conflict and tension. The other is complex about not-specializing security, which causes discord with his/her supervisor or co-workers and a feeling of uneasiness. 2. Factors of stress related to human relationship. The stress due to human relations is constantly resulted from discord with his/her supervisor and inclined to be accumulated. The mental conflict is elated in feeling that the manager's instructions are not right. So this factor makes them want change of occupation. Also working conditions are different from those of their friends, which causes them not to spend a lot of time with their friends. 3. Factors of stress related to domestic life It appears that most security guards are under stress due to their spouses' discontent with a small number of wages. Also it is reported that male guards are under stress in case of unhappy conjugal relations. And security guard's life is restricted much more than that of workers in a general occupation because of standing ready for mobilization and 24-hour service. So some of male guards experienced an early symptoms of a morbid suspicion about their wife's chastity and are suffering from insomnia as an occupational disease.

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An Analysis of Fall Incidence Rate and Its Related Factors of Fall in Inpatients (입원환자 낙상 발생 실태와 원인에 관한 분석 연구)

  • Kim, Chul-Gyu;Suh, Moon-Ja
    • Quality Improvement in Health Care
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    • v.9 no.2
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    • pp.210-228
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    • 2002
  • Background: The purpose of this research was to examine the fall incidence rate and its related factors of fall in inpatients. Methods: The data were collected from the 138 fall incident reports in one tertiary hospital in Seoul from April 1st 1999 to September 30th 2001. The Fall Incident Report Form was originally developed based on that of Massachusetts General Hospital revised in 1995. And this was modified for this survey by the collaborating work of QI team including researcher and department of nursing service of this particular hospital. The contents of Fall Incident Form were general characteristics of patient. factors related to fall. types and places of fall. circumstances, nursing interventions. and outcome. Results: 1) The incidence rate of fall was 0.08% of total discharged patients and 0.081 per 1000 patient-day. This incidence rate is much lower than that of several hospitals in USA. This finding might result from the different incidence report system of each hospital. 2) The characteristics of fall-prone patient were found as follows. They were mostly over 60 years old, in alert mental status, ambulatory with some assistance, and dependent on ambulatory device. The types of diseases related high incidence rate were cerebrovascular disease(3.2), hypertension(1.6), cardiovascular disease(1.4), diabetes(1.3) and liver disease(0.6). 3) The majority of fall events usually occurred m bed. bedside(walking or standing) and bathroom in patient room. Usually they were up on their own when they fell. And there were more falls of elderly occurred during night time than day or evening. 4) 63.8% of fall events resulted in physical injuries such as fracture and usually the patients had diagnostic procedures and some treatment(ex. suture) which caused additional cost to the patients and their families. 5) The found risk factors of fall were drugs(antihypertensive drug, diuretics) and environmental factors like too high bed height, long distance of bedside table and lamp switch, and slippery tile of bathroom floor. Conclusion: Considering these results, every medical and nursing staff should be aware of the risk factors of patients in hospital, and should intervene more actively the preventive managements, specially for the elderly patients during night. Therefore, it is recommended that the development of Fall Prevention Programs based on these results.

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A scheme on strengthening of R.O.K reserved force (예비전력 정예화 방안)

  • Kim, Jae-Sam
    • Journal of National Security and Military Science
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    • s.5
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    • pp.1-45
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    • 2007
  • Reserved forces of ROKA are in charge of replacement of TOE in the wartime and mission of rear area operation. But there is institutional inertia in the law and organization oriented to fill human resources rather than take mission. We need to prepare for the investment and arrangement of reserved forces as military power that would be replaced standing forces. In this portion, to reinforce reserve forces elite, First, efficient mobilization regulations and systems are suggested. I covered a maintenance of relevant mobilization ordinances which need to legislated and approved by national assembly for wartime and development of mobilization system which might lose the appropriate time for mobilization due to complicated declaration procedures and measures to overcome the panic at the initial stage of the war and organization and employment of nationwide transportation system and mobilization center. To ensure efficient resource management and mobilization of reserve forces with a number of approximately 3 million, there's a necessity of organization for integration and conciliation. To make it real, I suggested establishing and employing the mobilization center, on first phase, employ the mobilization center focusing on homeland divisions, on second phase, it is advisable to convert to national level mobilization system and develop to central mobilization center focusing on national emergency planning committee. During peacetime, in conjunction with Mobilization Cell, mobilization center can conduct resource survey and integrate and manage mobilization resources and take charge of mobilization training of subordinate units, and during wartime, in conjunction with mobilization coordination team and Cell, can ensure the execution of mobilization. Second, Future oriented reserve forces management system such as service system of reserve forces and support system of homeland defense operations. Current service and trainings of reserve forces by the year have very low connection, as it is very complex to manage the resources and trainings, and service and training lack the equity, re-establishment of service system is required. Also in an aspect of CSS and cultivation support for reserve forces, as the scope and limitation of responsibility between the armed forces and autonomous organization is obscure, conditions to conduct actual-fighting exercises are limited. Concentrated budgetting is extremely difficult because reserve forces training fields are scattered nationwide, and facilities and equipments are rapidly getting older. To improve all these, I suggest the organization of homeland defense battalion with a unit of "City-Gun-District" and supporting the local reserve forces. Conduct unit replacement or personal replacement for those who have finished their 1 or 2 years and homeland defense operation duty for those with 3-5 years for consistency and simplification. Third, I suggest Future oriented Reserved Training(FRT) and Training Center oriented training management to establish a reliable reserve training. Reserves carry out expansion of unit, conventional combat mission, homeland defense and logistics support during wartime, and actual-fighting exercise, and disaster relief, peace keeping activities. Despite diverse activities and roles, their training condition still stays definitely poor. For these reasons, Modernization of weapons and facilities through gradual replacement and procurement is essential to enhance mobilization support system.

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