• 제목/요약/키워드: loading period

검색결과 635건 처리시간 0.028초

경안천 수질에 대한 환경기초시설 방류부하량의 영향 (The Effect of Discharge Loading at Sewage Treatment Plants on Water Quality in Kyoungan Stream)

  • 김호섭;이수웅;류덕희;공동수
    • 한국물환경학회지
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    • 제25권3호
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    • pp.452-458
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    • 2009
  • This study was carried out to assess the effect of discharge loading at sewage treatment plants (STP) on water quality in Kyoungan stream. The seasonal variations of water quality (BOD, COD, SS, TN, and chl.a) at site 1(Mesanribo) were similar with those at site 2(Sehabo). BOD, COD, SS, and chl.a concentration were also similar except for TN and TP concentration which were lower than those at site 1. The BOD, COD, TN, TP and chl.a concentration at site 2 in dry period were higher than that of wet period. The ratios of BOD, TP, COD, SS discharge loading at all STP in Kyoungan stream watershed to delivery loading at site 2 were 0.69, 0.54, 0.48, 0.31, and 0.26 on average, respectively. Both site 1 and site 2, the seasonal variations of discharge loading at STP did not showed any relationship with those of water quality. The mean ratios of inflow loading at site 1 to delivery loading at site 2 were relatively high that ranged from 0.43 to 0.61. In dry period, the ratios of discharge loading at STP in Sehabo watershed to delivery loading at site 2 were below 0.2 except for BOD (0.24), and decreased <0.1 in wet period. While, SS loading from watershed between site 1 and site 2 to delivery loading at site 2 ratios increased in wet period.

SWMM 모형을 이용한 유역의 오염부하량 산정 (Estimation for Watershed pollutant loading with SWMM)

  • 전지홍;윤춘경
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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    • pp.689-694
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    • 1999
  • This study estimated average yearly watershed pollutant loading by using SWMM(Storm Water Management Model) which is one of the nonpoint source quality models. Two sites were measured discharge and water quality at dry period and wet period. The rainfall data is used from 1989 to 1998 . During a decade, the average year watershed pollutant loading, which is SS, BOD5 , TN, TP, were 2.39E+06kg, 0.92E +05kg, 2.53E+05kg, 2.66E+04kg respectively. During dry period, SS, BOD5 TN, TP loadings were 1.89E+05kg, 1.7E+05kg, 1.04E+05kg, 1.11E+04kg, and during wet period 1.89E+05kg, 1.17E+05kg, 1.04E+05kg, 1.11E+04kg respectively so wet period loading are more than dry day loadings.

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해상운송인의 책임기간에 관한 고찰 (A Study on the Period of Carrie's Responsibility)

  • 조종주
    • 한국항만경제학회지
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    • 제18권2호
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    • pp.135-151
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    • 2002
  • This study focuses on analysing the period of carrier's responsibility. The Hague Rules apply only while the cargo is in carriage. This period of carrier's responsibility begins when the ship' tackle is hooked on the goods for loading and continues until they are unhooked from the lifting gear after discharge. The Hague Rules are consequently said to apply from tackle to tackle. Also The Hamburg Rules lays down the basic principle that the carrier will be responsible for the goods during the time he is in charge of them at the port of loading, during the carriage and at the port of discharge. These period of carrier's responsibility should be determinated according to custom of the port of loading and discharge because of the importance of local custom in the loading and discharge of goods.

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Double-Side Notched Long-Period Fiber Gratings fabricated by Using an Inductively Coupled Plasma for Force Sensing

  • Fang, Yu-Lin;Huang, Tzu-Hsuan;Chiang, Chia-Chin;Wu, Chao-Wei
    • Journal of the Korean Physical Society
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    • 제73권9호
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    • pp.1399-1404
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    • 2018
  • This study used an inductively coupled plasma (ICP) dry etching process with a metal amplitude mask to fabricate a double-side notched long-period fiber grating (DNLPFG) for loading sensing. The DNLPFG exhibited increasing resonance attenuation loss for a particular wavelength when subjected to loading. When the DNLPFG was subjected to force loading, the transmission spectra were changed, showing a with wavelength shift and resonance attenuation loss. The experimental results showed that the resonant dip of the DNLPFG increased with increasing loading. The maximum resonant dip of the $40-{\mu}m$ DNLPFG sensor was -26.522 dB under 0.049-N loading, and the largest force sensitivity was -436.664 dB/N. The results demonstrate that the proposed DNLPFG has potential for force sensing applications.

다양한 Sinusoidal 하중을 받는 아스팔트콘크리트 혼합물의 Moduli 값에 대한 비교연구 (Fundamental Comparison of Moduli Values in Asphalt Concrete Mixture due to Various Sinusoidal Loadings)

  • 김낙석
    • 한국방재학회 논문집
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    • 제6권1호
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    • pp.39-48
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    • 2006
  • 본 시험은 다양한 sine파형을 가진 인장 및 압축 하중 하에서 아스팔트 혼합물의 모듀율값 을 비교평가하기 위하여 수행되었다. 즉, 휴식시간을 가진 반복 인장 haversine 하중, 휴식시간을 가진 반복 압축 haversine 하중, 주기적 인장하중, 주기적 압축하중, 그리고 주기적 인장-압축 반복하중이라는 총 5개의 하중형태가 32, 50, 68, 86, $104^{\circ}F$ (0, 10, 20, 30, $40^{\circ}C$) 라는 5개의 온도하에서 평가되었다. 시험결과, 휴식시간을 가진 반복 haversine 하중으로 인한 아스팔트 콘크리트의 인장 및 압축 모듀율 값은 저온에서 유사한 값을 나타내었지만, 고온에서는 상이한 값을 보였다. 특히, 고온에서 압축 모듀율 값은 인장 모듀율 값보다 높은 수치를 보였다. 또한, 저온에서 일축 직접인장 시험으로부터 구한 모듀율 값은 간접 인장시험으로부터 구한 모듀율 값보다 높은 값을 나타내었다. 그러나, 고온에서는 서로 유사한 값을 보였다. 일반적으로, 휴식시간을 갖는 반복 haversine 하중을 이용하여 얻은 모듀율 값은 주기적 sine파형을 가진 하중으로부터 구한 모듀율 값보다 항상 낮은 값을 나타내었으며 그 두 가지 하중으로부터 구한 모듀율 값의 차이는 온도가 감소함에 따라 더욱 증가되었다.

Prospective randomized clinical trial of hydrophilic tapered implant placement at maxillary posterior area: 6 weeks and 12 weeks loading

  • Kim, Seong-Beom;Yun, Pil-Young;Kim, Sang-Yun;Yi, Yang-Jin;Kim, Ji-Yun;Kim, Young-Kyun
    • The Journal of Advanced Prosthodontics
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    • 제8권5호
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    • pp.396-403
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    • 2016
  • PURPOSE. Early loading of implant can be determined by excellent primary stability and characteristic of implant surface. The implant system with recently improved surface can have load application 4-6 weeks after installing in maxilla and mandible. This study evaluated the effect of healing period to the stability of hydrophilic tapered-type implant at maxillary posterior area. MATERIALS AND METHODS. This study included 30 patients treated by hydrophilic tapered-type implants (total 41 implants at maxilla) and classified by two groups depending on healing period. Group 1 (11 patients, 15 implants) was a control group and the healing period was 12 weeks, and Group 2 (19 patients, 26 implants) was test group and the healing period was 6 weeks. Immediately after implant placement, at the first impression taking, implant stability was measured using Osstell Mentor. The patients also took periapical radiographs after restoration delivery, 12 months after restoration and final followup period. The marginal bone loss around the implants was measured using the periapical radiographs. RESULTS. All implants were survived and success rate was 97.56%. The marginal bone loss was less than 1mm after 1 year postoperatively except the one implant. The stabilities of the implants were not correlated with age, healing period until loading, insertion torque (IT), the diameter of fixture and the location of implant. Only the quality of bone in group 2 (6 week) was correlated with the stability of implant. CONCLUSION. Healing period of 6 weeks can make the similar clinical prognosis of implants to that of healing period of 12 weeks if bone quality is carefully considered in case of early loading.

계절에 따른 비강우시 팔당호의 유기물 유입부하량 (Loading of Organic Matter according to Seasonal Changes into Lake Paldang during Non-storm Period)

  • 길경익;신지웅;허진
    • 한국물환경학회지
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    • 제27권4호
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    • pp.433-437
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    • 2011
  • The study is conducted to evaluate loading of organic matter as seasonal changes during non-storm period into Lake Paldang which is used to a major drinking water source. Samples were taken in Lake Paldang intake during non-storm period and were analyzed loading of organic matter. From the results of the survey, improving of the water quality showed remarkable tendency depending on the changing periods from summer to fall and from fall to winter. Dilution effect from the increase of base run-off caused by the concentrated rainfall in rainy season, the characteristics of Korea's climate seems to have to be the reason. On the other hand, deteriorating of the water quality showed tendency depending on the changing periods from winter to spring and from spring to summer. Increase of Cyanobacteria etc. is explained by seasonal effects which are a small amount of the rainfall in winter and spring and gradational increase of water temperature.

점토의 1차원 압밀과정에 있어서 재하시간과 층두께에 대한 상사법칙에 관한 연구 (A Study on Similarity Rule of Loading Period and Thickness with One-dimensional Consolidation Process for Clay)

  • 김재영;오시마 아키히코
    • 대한토목학회논문집
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    • 제26권6C호
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    • pp.369-376
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    • 2006
  • 1차원 압밀시험에서 구해진 결과는 상사법칙을 적용하여 원지반의 침하량과 압밀시간을 추정하고 있다. 하지만 점토의 변형의존성, 층두께, 재하시간, 하중증분비 등에 의해 변화하기 때문에 상사법칙의 성립은 명확하게 밝혀지지 않고 있다. 본 연구는 재하시간과 층두께를 달리하여 압밀시험과 투수시험을 병행하여 상사법칙의 적용성을 나타내었다. 그 결과, f(=1+e)-logk관계는 점토의 특성을 잘 나타내고 있으며, $c_{\nu}$와 k는 보정이 필요없는 것으로 나타났으며, 상사법칙은 f-logp관계의 위치와 1차 압밀선에 의존하고 있다.

Marginal bone level change during sequential loading periods of partial edentulous rehabilitation using immediately loaded self-tapping implants: a 6.5-year retrospective study

  • Wang, Jing;Zhang, Zhengchuan;Deng, Feilong
    • The Journal of Advanced Prosthodontics
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    • 제14권3호
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    • pp.133-142
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    • 2022
  • PURPOSE. A large number of studies have suggested the practicability and predictability of immediate implant function, but few studies have reported marginal bone level changes during sequential loading periods. The purpose of this study was to evaluate the marginal bone remodeling of immediately loaded self-tapping implants both at each time point and during each loading period between two time points. MATERIALS AND METHODS. The patients included in this retrospective study were treated with immediately loaded NobelSpeedy Replace implants between August 2008 and July 2009. Differences in the marginal bone level (MBL) at each time point and the marginal bone level change (ΔMBL) between two time points were analyzed with Bonferroni correction (P < .05). RESULTS. Overall, 24 patients (mean age, 47.3 ± 12.8 years) with 42 immediately loaded implants and a median follow-up of 6.5 years (IQR, 67.8 months) were included. The cumulative survival rate after 10 - 12 years was 95.2%. Continuous but slow marginal bone loss was observed during long-term follow-up. MBL at both 7.5 years and 11 years was significantly lower than that at loading, 6 months, 2 years and 4 years (P < .05). No bone loss difference was found in any period before 4 years of follow up (P > .05). The loading period of 4 years to 7.5 years showed the largest ΔMBL compared to those of other time periods (P < .05). CONCLUSION. Slight bone loss occurred continuously, and more radical changes of marginal bone can be observed during the period of 4-7.5 years. Thus, long-term effective follow-up of immediately loaded implants is needed.

임플란트주위골 흡수 및 상악전치부 치조제 형태와의 관계에 대한 방사선학적 연구 (RADIOGRAPHIC STUDY OF PERI-IMPLANT BONE LOSS AND ITS RELATIONSHIP TO THE MORPHOLOGY ON MAXILLARY ANTERIOR ALVEOLAR RIDGE)

  • 이준휘;홍종락;김창수
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제32권6호
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    • pp.575-579
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    • 2006
  • Purpose : The purpose of this study was to evaluate peri-implant bone loss and implant success on anterior maxillary alveolar ridges and Compare Class III and Class IV ridges in the aspect of peri-implant bone loss. Material and Methods : 14 patients (aged 21 to 68, 6males and 8females), who lacked maxillary anterior teeth and were installed from January 2000 to April 2003 at Samsung Medical Center, were selected. The type of implant used included 30 $Br\ddot{a}nemark$ implant. They were taken with digital tomographic and conventional intraoral radiographic examinmation, and were treated with implant installaion without bone augmentation. The peri-implant bone resorption was measured at the mesial and distal aspect of implant on the conventional intraoral radiographs. Results : The study classified the anterior maxillary alveolar ridge and measured peri-implant bone resorption from the period of implant installation to the 2nd year after functional loading radiographically. The study revealed no statistically significant difference between two groups, which was classified by its morphology. The average bone resorption on healing period before loading was 0.18mm and 0.18mm, the 1st year of loading period, 0.77 mm and 0.84mm, and on the 2nd year of loading period, 0.07mm and 0.06mm, respectively on both Class III and class IV. Conclusion : In the knife edge form of anterior maxillary residual ridges(Class IV), implant placement without ridge augmentation does not have significant difference with that of Class III alveolar ridge in the concern of Implant success after 2 year functional loading period in the aspect of peri-implant bone resorption radiographically.