• Journal of Animal Science and Technology
• /
• v.45 no.4
• /
• pp.607-616
• /
• 2003

This study was conducted to determine the effect of feeding a total mixed ration(TMR) of broiler litter(BL) and bakery by-product(BB) with additional BL or rice straw incorporated at 10% of dietary DM as a roughage source on behavior pattern, nutrient intake, digestibility, digestible nutrient intake, ruminal and blood parameters, and N balance of sheep. All the treatment diets were formulated to be isoenergetic[total digestible nutrients(TDN) 66.9%]. Compared with the conventional formulated feed - rice straw feeding system(control), feeding TMR with BL(T1) or rice straw(T2) at 10% of dietary DM resulted in reduced eating, ruminating and total chewing time(P<0.05), similar DM intake, low(P<0.05) digestible DM, OM, fiber and total nutrients intake, low(P<0.05) nutrients digestibilities except EE, similar ruminal characteristics(pH, VFA concentrations and ratios, efficiency of carbohydrate fermentation, NH3-N), and favorable N digestion and retention. There were no differences in the above parameters between T1 and T2 with the exception of increased(P<0.05) eating, ruminating and total chewing time for T2. These results suggested that a TMR of BL and BB with or without rice straw may replace the conventional formulated feed and rice straw in ruminant diets successfully and furthermore feeding the TMR with rice straw made sheep behavior pattern more favorable.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
• /
• 2000.11a
• /
• pp.132-132
• /
• 2000

환경오염과 이상기후의 영향으로 인한 수자원의 고갈과 함께 국내의 경우 수자원 개발 계획 및 수요량을 감안할 때 향후 7 년 내에 물부족 현상을 겪을 것이라는 보고가 있 었으며, 환경부담을 줄이기 위해 폐수의 배출기준은 강화되고 있다. 이러한 상황에서 제조 특성상 타 업종에 비해 폐수 발생량이 높은 편인 국내의 제지산업은 여러 해전부터 이에 대 한 방안을 모색하여 왔다. 일반적으로 폐수 수질 관리와 청수 사용량의 절감을 위해 고가의 폐수 처리 장치를 설치하거나 폐수 재활용을 통해 공정을 극도로 폐쇄화하는 방안으로 연구 가 진행되어 왔다. 이 중 용수의 재활용이 가장 경제적인 방법이지만, 재활용이 지속될수록 각종 무기염과 콜로이드성 유기물질이 축적되어 각종 약품의 효능 저하, 탈수속도의 저하 및 생산 제품의 품질 악화 등의 문제를 유발한다고 알려져 있다. 이를 해결하고자 하는 노 력으로 펄프 원료에 따른 공정수 내 용해성 물질의 분석과 재활용 횟수에 따른 각종 SS와 D DS의 축적 정도에 대한 기초 연구가 수행되었으며, 고폐쇄화된 공정에서 성능을 발휘할 수 있는 첨가제의 개발과 적용 방법에 대한 연구도 수행된 바 있다.여러 지종 가운데 골판지 원지는 용수의 재활용률이 상당히 높은 지종이기 때문에 공정수의 재활용이 진행될수록 열악한 저급 원료로부터 각종의 다양한 물질이 용출 혹은 배 출되며, 이러한‘물질은 골판지 원지의 강도 발현에 더욱 악영향을 미칠 것으로 판단되었다. 미세분으로 구성된 SS의 경우 이미 많은 연구를 통해 특성이 파악되었기 때문에 본 연구에 서는 ss를 제외한 공정수를 두 가지로 크게 나누어 고려하였다. 즉, ss로 측정되지 않지만 닥도를 유발할 수 있는 미세 무기물질과, 용해성의 무기염, 첨가제 및 추출물 둥으로 이루어 진 용해성 성분으로 나누어 분석하였으며, 또한 각각이 초지 특성에 미치는 영향을 살펴보 고자 하였다.을 해석코자 하였으며, 그 방법으 로 수치해석기법을 도입하였다. 또 실제 캘린더링 전후의 두께 변화를 측정하여 유리전이온도 의 도달 깊이와 비교하였다. 지필의 압축 정도는 롤의 직경과 닙 폭을 이용하여 MD 방향으 로 함수화하였으며, 열전달 계수로는 겉보기 값을 사용하였다. 이때 지펼은 균질한 것으로 가 정하였다. 함수율은 유리전이온도를 좌우하는 가장 큰 인자이나 본 연구에서는 항온항습처리 를 통해 유입지의 함수율을 고정시켰으며 캘린더링 시 함수율의 변이는 없다고 가정하였다. 그 결과 열침투깊이가 증가할수록 지필은 보다 변형되기 쉬운 상태가 되어 주어진 압력 조건에 대해 소성변형 정도가 증가하는 것으로 나타났다. 이는 캘린더링 전후에 두께 변화를 측정하여 정량적으로 평가할 수 있었다. 수치해석기법을 통해 같은 압력 조건에서 온도가 증 가함에 따라 혹은 같은 온도 조건에서 압력이 증가함에 따라 지필 내의 유리전이온도의 침투 깊이가 증가함을 알 수 있었으며 이는 캘린더링 전후의 두께 변화의 측정 결과와 일치하였 다. 또 NRT가 증가함에 따라서도 유리전이온도 침투 깊이가 증가하였다.합편에 비해 일부 우수한 양상을 보였지만 본 실험의 범위내에서는 통계적 정량적 차이를 제시할 수는 없었다. 향후 보다 광범위한 동물 실험이 필요할 것으로 사료된다.된다.하고도 완전교정술 도달 확률이 높은 치료전략이라는 사실을 입증하였으며 주대동맥폐동맥혈관부행지의 크기나 숫자가 단일화하기 쉬운 형태학적 특징을 지닌 경우에는 조기에 일단계완전교정술을 시행하여 양호한 결과를 얻을 수 있다는 사실을 발견하였다. 반면 본 환아군 중 단일화술을 먼저 시도한 군에서는 비록 단계적인 단일화를 시도한 군에서 단일화술과 관계된 수술사망율이 약간 낮기는 하였으나 완전교정술까지 완료될 가능성에는 차이가 없었다. 그러나 이 경우 보다 정련된 적응 환자의 선택을 통한 단일화 우선전략의 시도와 장기 추

• Journal of Aquaculture
• /
• v.7 no.3
• /
• pp.165-175
• /
• 1994

Attempts were made to find out nitrogen and phosphorus loads to aquatic environment resulting from feeding Nile tilapia (Oreochromis niloticus). Two different size groups, small and large, were used. The average sizes of small and large tilapia were 65.2 g and 389.2 g respectively, and three kinds of commercial diets were used for each size. The 3 kinds of commercial diets for tilapia contained in average 33.8% crude protein ($5.4\%$ nitrogen) and $1.4\%$ total phosphorus. The load of nitrogen and phosphorus were measured by subtracting the amounts of nutrients retained in the body of fish from consumed nutrients. Sixty, five percentage of total feces was excreted within 24 hours after feeding at $23^{\circ}C$. Nitrogen content in the feces was higher in large fish than small ones. The apparent digestibility of dietary protein for small and large tilapia was $90.0\%$ and $89.7\%$, respectively. Availability of dietary phosphorus for small and large tilapia was $44.7\%\;and\;51.4\%$, respectively. The total load of nitrogen and phosphorus per 1 metric ton of tilapia production was 49.5kg and 6.3kg, respectively, for small ones with feed conversion ratio (FCR) of 1.4, and 61.3 kg and 13.4kg, respectively, for large ones with the FCR of 1.8. Nitorgen balance appeared that small and large tilapia excreted $7.1\%\;and\;9.9\%$ of consumed nitrogen through fecal-nitrogen and $55.5\%\;and\;62.3\%$ through urine and gills, retaining $37.4\%\;and\;27.8\%$ in the body, respectively. These results show that small fish pollute less than large fish, excreting less and retaining more nutrients in the body.

• Journal of Bio-Environment Control
• /
• v.28 no.4
• /
• pp.352-357
• /
• 2019

In this study, we investigated the limit temperature range which is effective for dormancy release of 'Hongro' and 'Fuji' apples during the endodormancy period. The germination rate was 50% or more in all treatments except of 'Hongro' $-5^{\circ}C$ treatment. The germination rate of 'Fuji' was 86.3% at the temperature of $-5^{\circ}C$. The concentrations of carbohydrate and mineral components were significantly different between treatments but did not show any tendency or specific change. However, the sorbitol contents of 'Hongro' $-5^{\circ}C$ treatment were higher at 29.62 mg/g than those of 'Fuji', which was not affected for dormancy release. The results of hormone analysis showed that ABA(abscisic acid) and JA(jasmonic acid) in 'Hongro' $-5^{\circ}C$ treatment were respectively 176.48 and 15.72 ng/g. ABA, JA and SA(salicylic acid) contents in 'Fuji' apple tree were significantly lower than those of 'Hongro'. As a result of this study, the limit temperature range effective for dormancy release was different according to the varieties, and 'Hongro' did not affect with 30.3% of germination rate at $-5^{\circ}C$. However, 'Fuji' is 86.3% even at $-5^{\circ}C$ it was suggested that 'Fuji' had a chilling accumulation for dormancy release.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2009.05a
• /
• pp.271-275
• /
• 2009

본 연구에서는 상수관로의 잔존수명을 통계적 기법 중 하나인 비례위험모형(PHM)에 적용하여 평가하였다. 비례위험모형을 구축하기 위한 개별관로의 생존시간은 관로의 파손율이 한계파손율에 도달하는 시간으로 정의하였다. 즉, Park and Loganathan(2002)에서 제시한 GPBM을 적용하여 시간에 따른 개별관로의 파손율을 추정하고 추정된 파손율과 한계파손율의 상등관계를 통해 생존시간을 산정하였다. 또한, 본 연구대상관로에 대한 GPBM을 구축함에 있어, 매설시점에서 누적파손횟수를 0으로 한 파손기록을 입력자료에 추가하는 방법과 가중계수(WF)의 범위를 수정함으로써 기존의 GPBM을 보완하였다. 이로써 파손사건이 최소 1회 이상 기록된 강관 및 주철관에 대한 비례위험모형을 구축하였다. 이와 같이 수정된 방법론은 관로 파손사건 등의 자료의 축적이 미비한 국내 여건에서 비례위험모형 및 GPBM과 같은 통계적 모형을 구축할 때 유용할 것으로 사료된다. 본 연구대상관로의 비례위험모형에 포함된 유의한 공변수는 관종과 관경 그리고 길이이며 관종은 비례성 가정을 위배하여 시간종속형 변수로 모형화되었다. 최종 채택된 PHM모형을 통해 생존함수를 추정하였으며 추정된 생존함수를 이용하여 개별관로의 잔존수명 및 경제적 수명 그리고 각 수명에 대한 95% 신뢰구간을 산정하였다. 또한 개별관로의 경제적 수명에 영향을 미치는 공변수의 위험비율도 분석하였다. 분석결과 강관의 평균 경제적 수명은 약 25.1년이고 주철관은 약 21년으로 산정되었다. 또한 관종에 따른 경제적 수명에 도달할 상대적인 위험률은 전반적으로 주철관이 높으나 20년 이상 매설된 관로에서는 강관의 위험률이 높을 것으로 분석되었다. 관경과 길이는 크기에 비례하여 상대적 위험률도 증가하였다.

• Economic and Environmental Geology
• /
• v.35 no.2
• /
• pp.163-170
• /
• 2002

The purpose of this study is to analyze the relationship between geology and geothermal gradient in South Korea using GIS. For the analysis, 352 temperature logging wells were constructed to spatial database and the relationships beween geothermal gradient and geological time and lithology were analyzed using the overlay the wells layer and 1:1,000,000 scale geological map layer. The average of the geothermal aradient of South Korea is 29.34$^{\circ}C$/km. In the geologic sequence, Cenozoic strata has 39.7$0^{\circ}C$/km, Mesozoic strata has 30.63$^{\circ}C$/km , Paleozoic strata has 22.32$^{\circ}C$/km, Proterozoic strata 23.15$^{\circ}C$/km geothermal gradient value. In the lithological aspect, plutonic rocks 33.96$^{\circ}C$/km, sedimentary rocks have 24.78$^{\circ}C$/km and sedimentary and volcanic rocks have 26.85$^{\circ}C$/km geotermal gradient value. The result can be used to develop geothermal energy and hot spring as a reference.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.27 no.3
• /
• pp.206-217
• /
• 1982

This experiment was conducted to study about nutrient absorption of flag leaf and chaff of rice plant different transplanting date with elevations. Heading stage was delayed by destructive cold temperature or late transplanting. Plant analyses revealed that above poor plants also had higher total nitrogen content, but ower silicate in the flag leaf and sterile chaff. Total nitrogen and silica contents to accumulated in flag leaf between yield was significant high correlation. The chaff of late transplanting and sterility was high total nitrogen. Relationship between silicate absorption and total nitrogen of chaff was significant high correlation. Ripening temperature after heading stage was influenced total nitrogen of chaff. Phosphate, potassium, calssium and silicate contents of chaff increased hight ripening temperature but total nitrogen decreased. Therefore, inorganic element contents of chaff was closely connected with grain sterility.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.26 no.6B
• /
• pp.669-675
• /
• 2006

Intermittent aerobic digestion experiments using a sequencing batch reactor (SBR) were carried out in this study. Aeration ratio was found to be an important operation factor for the reduction of solids and nitrogen. As the sludge digested, organic nitrogen was released from the solids and oxidized to nitrate nitrogen. Biological denitrification was also significant and the denitrification rate was limited by aeration ratio. Under the condition of 0.25-0.75 of aeration ratio, acclimation of ammonia nitrogen was not observed and pH were preserved near neutral in the intermittent aerobic digestion. As the aeration ratio increased, solids reduction was increased whereas dissolved nitrogen removal was decreased. Based on the experiments, 17-2% of VSS reduction and over 80% of dissolved nitrogen removal were practicable by intermittent aerobic digestion using a SBR when the MSRT were designed 8-32 days and aeration ratio was operated about 0.25-0.75.

• The Korean Journal of Ecology
• /
• v.4 no.3_4
• /
• pp.59-67
• /
• 1981

Stomatal resistances of the leaves in Heteromeres arbutifolia and of the stems in Ferocactus acanthodes were studied to estimate active and passive behaviors of the guard cells on a theoretical basis. Active and passive stomatal responses to light and water deficit were observed. When the change rate of existent water due to variation of osmotic potential in the guard cells and the loss rate of transpirational water from the guard cells are $\Delta$wi-$\Delta$wt and leaded to active behaviors for opening and closing stomata. However, when stems of F. acanthodes with stomata closecd under the solar irradiation were covered with black cloth and then taken off, behaviors of the guard cells occurred in the condition of $\Delta$wi<$\Delta$wt and were passive. Under the conditiion of $\Delta$wi<$\Delta$wt due to cutout from stems, passive behaviors of the guard cells in H. arbutifolia and F. acanthodes always occurred in spite of the solar irradiation and darkness, respectively. The transpirational resistance coefficients of the guard cells in stems of F. acanthodes (0.380) and Opuntia bigelovii (0.135) wer emuch higher than in leaves of H. arbutifolia (0.034). Moreover, stomatal opening in stems of F. acanthodes during the daytime could be induced by watering. Those results are interpreted as that since the guard cells in desert Crassulacean acid metabolism (CAM) plants always exist in the state of stomatal opening, nocturnal stomatal opening and daytime stomatal closing are exhibited by passive behaviors of the guard cells in the alternant conditioins of $\Delta$wi>$\Delta$wt and $\Delta$wi<$\Delta$wt, respectively.

• Journal of Korean Society of Forest Science
• /
• v.98 no.3
• /
• pp.263-271
• /
• 2009

This study aims to identify negotiation alternatives related to Post-2012 reducing emissions from deforestation (RED) and enhancement of forest carbon stock (EFCS) activities. It also aims to recommend a negotiation strategy considering environmental integrity and national interest on the basis of estimating reduction potentials of each alternative on the assumption that tradable carbon credits play an important role as positive incentives. In order to estimate greenhouse gas (GHG) reduction potentials and income potential from RED and EFCS activities, 99 countries were selected by the Global Forest Resources Assessment of the Food and Agriculture Organization of the United Nations. A 'baseline and credit' method was applied to estimate RED activities. Gross-net and net-net methods were applied for EFCS activities. According to the results, Brazil, Indonesia, and the Democratic Republic of Congo have more potential to get positive incentives through RED, while China, Chile, and the Republic of Korea have more potential to get positive incentives through EFCS. This study suggests including both RED and EFCS activities in the boundary of policy approaches and endowment of positive incentives to consider GHG reduction potentials in the global scale and equity among developing countries. Making a discount rate application of forest management activities can be also recommended to factor out the effects of human-induced activities by EFCS activities.