Journal of Korean Society for Atmospheric Environment
/
v.15
no.5
/
pp.545-554
/
1999
We would like to develop a short-term model to predict the time-related concentration of ozone whose reaction mechanism is complex. The paper targets Seoul where an ozone alert system has recently been employed. In order to develop a short-term prediction model for ozone, we suggested the Ozone Peak Indicator(OPI), an equivalent of the potential daily maximum ozone concentration, with precursors being the only limiting factor, and we calculated the Ozone Peak Indicarot as OPI={$rac{(O_3)_{max}cdot(H_{eH})_{max}(Rad)_{max}$ to preclude the influence of mixing height and solar radiation on the daily maximum ozone concentration. The OPI on the day of the prediction is to be calcultated by using the relation between OPI and the initial value of precursors. The basic prediction formula for time-related ozone concentration was established as $O_3(1)={(OPI)cdot Rad(t-2)H_{eH}}$, using the OPI, solar radiation two hours before prediction and mixing height. We developed, along with the basic formula for predicting photochemical oxidants, "SEOM"(Seoul Empirical Oxidants Model), a Fortran program that helps predict solar radiation and mixing height needed in the prediction of ozone pollution. When this model was applied to Seoul and an analysis of the correlation between the observed and the predicted ozone concentrations was made through SEOM, there appeared a very high correlation, with a coefficient of 0.815. SEOM can be described as a short-term prediction model for ozone concentration in large cities that takes into account the initial values of precursors, and changes in solar radiation and mixing height. SEOM can reflect the local characteristics of a particular and region can yield relatively good prediction results by a simple data input process.t process.
Journal of Korean Society of Coastal and Ocean Engineers
/
v.33
no.6
/
pp.238-245
/
2021
In this study, we carried out case study to predict dissolved oxygen (DO) concentration of Nakdong river estuary with LSTM model. we aimed to figure out a optimal model condition and appropriate predictor for prediction in dissolved oxygen concentration with model parameter and predictor as cases. Model parameter case study results showed that Epoch = 300 and Sequence length = 1 showed higher accuracy than other conditions. In predictor case study, it was highest accuracy where DO and Temperature were used as a predictor, it was caused by high correlation between DO concentration and Temperature. From above results, we figured out an appropriate model condition and predictor for prediction in DO concentration of Nakdong river estuary.
In this study, a dry single-phase anaerobic digestion process (Dranco system) was investigated to evaluate the optimum operational conditions. Several factors such as injection rate of organic waste, biogas production, $CH_4$ content in the biogas, pH of the sludge, $NH_3$-N and VFA concentration were investigated based on the operation of the digestion process for 2 months (short term) and 8 months (long-term). The operation results showed that a small quantity of food waste should be injected every week and that a 10% increase of the microorganism injection rate should be needed. However, normal operation was conducted after 11 weeks based on the designed quantity. The $CH_4$ content in the biogas was high at the beginning and the end of the food injection. However, it was low during week days. When the biogas production was high, the $CH_4$ concentration was low. The biogas production increased with an increase of the injection rate. $100m^3$/ton of biogas was produced from normal operation of the digestion process based on the designed quantity. The pH values of the digestion tank based on short-term operation ranged from 8 to 8.5. However, the pH values ranged from 7.45 to 8.15 after 4 weeks of long-term operation. The $NH_3$-N concentration of short-term operation ranged from 4,500 to 5,500 ppm and it gradually decreased to 2,000ppm after normal operation was commenced. For long-term operation, it was 5,000ppm initially and 3,800ppm after normal operation was commenced. The VFA concentration of sludge was less than 900ppm and 2,500ppm for short and long-term operations, respectively, after normal operation. Overall, the differences between sludge pH, $NH_3$-N and VFA concentrations may be due to the different types of microorganisms and the digestion ability of the microorganisms which exist in the accumulation of non digested organics. Moreover, it may be also caused by the type of food waste. Further investigation is needed to confirm these relationships.
Jun Sang Ahn;Eung Gi Kwon;Hyun Jeong Lee;Ui Hyung Kim;Jeong Il Won;Sun Sik Jang;Byung Ki Park
Journal of Animal Science and Technology
/
v.65
no.1
/
pp.149-159
/
2023
The purpose of this study was to evaluate the effects of castration method and short-term fattening periods on Hanwoo cattle. Thirty-two Hanwoo calves (average body weight: 148.4 ± 19.8 kg) were used. The calves were randomly assigned in a 2 × 2 factor according to two castration methods (castration or hemi-castration) and two short-term finishing periods (24 months or 26 months). The final body weight increased significantly as the fattening period increased (p < 0.05), and the average daily weight gain was higher in the hemi-castration groups than in the castration groups (p < 0.05). After surgical castration, testosterone concentration was higher in the hemi-castration group than in the castration group during the entire experimental period (p < 0.05). The rib eye area was wider in the hemi-castration group than in the castration group (p < 0.01).An interaction effect was observed between the castration method and short-term fattening period (p < 0.05). Marbling and auction price scores differed between castration methods and were higher in the castration group than in the hemi-castration group (p < 0.01). Gross receipts and net income increased in the castration group compared to the hemi-castration group (p < 0.01) and showed a tendency to increase with the short-term fattening period, but there was no significant difference. Thus, castration to remove both testicles is essential for economic profit through producing high-quality Korean beef meat, and short-term fattening for 26 months, rather than 24 months, can benefit more by increasing carcass weight and meat quality.
Journal of Korean Society for Atmospheric Environment
/
v.29
no.5
/
pp.545-552
/
2013
While attainment rates for $SO_2$ and CO approached 100%, those for $PM_{10}$, $NO_2$, and $O_3$ have been low during the past decade. The attainment rates for 24-h $PM_{10}$ and 8-h $O_3$ have been only 1~3% and 5~12%, respectively, since the standards were strengthened in 2007. Variations in the 99th percentiles of 24-h $PM_{10}$, 8-h $O_3$, and 24-h $NO_2$, which are used as criteria for determining exceedance of standards, were examined by region. Because the analysis was based on short-term high-concentrations, the effects of Asian dust were observed for $PM_{10}$. Accordingly, it is necessary to specify whether exceptional events such as Asian dust will be included or not in determining the exceedances of standards. While variations in $NO_2$ were not large, there was an increasing trend in $O_3$. In the Yeongnam region, the increasing rate of $O_3$ concentrations was small although the decreasing rate of $NO_2$ was the greatest. In the Gangwon region, $NO_2$ concentrations were almost unchanged, but $O_3$ concentrations experienced a significant increase. Regional management strategies targeting short-term high concentrations of criteria pollutants analogous to the Special Act for the greater Seoul area will aid in improving attainment rates.
A simplified dilutor for cock spermatozoa at ambient temperature was achieved by adjusting the 5% concentration of fructose in isotonic saline. Motility of cock spermatozoa was arrested completely for maximum 6 hrs without affection the survivability of spermatozoa by employing this sugar. To study the effect of high concentration of fructose on fertility, sperm were inseminated with or without fructose at different hrs. Fructose from semen samples was removed by centrifugation. High fertility obtained in the hens inseminated with fructose free sperm (washed). In addition, washed sperm maintained the 85.00% fertility for 6 hrs in winter season ($17-21^{\circ}C$) and 82.67% fertility for 3 hrs in summer season ($31-35^{\circ}C$). Whereas control groups showed 47.33 and 25.33% fertility in winter and summer season respectively. No significant difference was found in percent motility and live counts between the control and washed experimental groups during winter season. However, these measures differed significantly in summer. Washing of cock spermatozoa more than once, high speed centrifugation and more duration for centrifugation proved harmful to fertility. It may be concluded that fructose (5%) can be used as a motility or metabolic inhibitor of spermatozoa for short-term storage of cock semen at ambient temperatures.
Kim, Hyun-Chul;Kum, Eun-Joo;Kwon, Do-Hyoung;Lee, Hye-Young
Biomedical Science Letters
/
v.15
no.3
/
pp.217-227
/
2009
The present study was set to evaluate the effect of pomegranate extracts on improvement of the menopausal syndromes such as face flushing in ovariectomized rats by carrying out short- and long-term experiments. Pomegranate extracts used to feed rats were prepared from the pulp part which does not contain the rid of the pomegranate, and were dissolved in propylene glycol. From the short-term (16 days) experiment, it was clear that when the 25, 250, 1,250 mg/kg/day concentrations of pomegranate extracts were orally fed to ovariectomized rats, the body temperature of the rats in all the 3 groups were decreased with statistical significance compared to other control groups which were fed with propylene glycol only. Especially, the body temperature decreased by $2.7^{\circ}C$ compared to control groups even when the pomegranate extracts were fed at the low concentration of 25 mg/kg/day implying the usefulness of pomegranate extracts in improving face flushing troubles. In addition, the body weight of the groups fed with pomegranate extracts also decreased when compared to groups fed with only propylene glycol, and the results were also statistically significant. In case of the estradiol level in the blood of rats, the levels were somewhat higher in the groups fed with pomegranate extracts than the control groups, even though the difference was not statistically significant. As found from the results of the short-term experiment, in long-term experiment, the groups fed with pomegranate extracts showed statistically significant decrease in the body temperature and the body weight, whereas the increase of the estradiol levels in blood in each groups were statistically insignificant. During the short- and long-term experiments, no sign of toxicity was found in rats fed with pomegranate extracts indicating no toxic side effects of the pomegranate extracts when orally fed. The concentrations of pomegranate extracts 25, 250, 1250 mg/kg/day treated to ovariectomized rats in this study can be estimated to be 1.5, 15, and 75 g/day when treated to women whose body weight is 60 kg which is average for women with menopausal syndromes. Since even the 75 g/day of high concentration of pomegranate extracts did not show any toxicity in short- and long-term experiments, taking 1.5 g/day concentration of pomegranate extracts would be safe dose for not causing any side effects. Therefore, it can be concluded from the results of this study that taking 1.5 g/day of pomegranate extracts for certain period time will improve the menopausal syndromes including face flushing.
Park, Min Hee;Park, Ji Eun;Kim, Min Seong;Lee, Kwon Young;Yun, Jung Im;Choi, Jung Hoon;Lee, Eunsong;Lee, Seung Tae
Journal of Embryo Transfer
/
v.29
no.3
/
pp.221-228
/
2014
Despite that porcine spermatogonial stem cells (pSSCs) have been regarded as a practical tool for preserving eternally genetic backgrounds derived from pigs with high performance in the economic traits or phenotypes of specific human diseases, there were no reports about precise definition of niche conditions promoting proliferation and maintenance of pSSCs. Accordingly, we tried to determine niche conditions supporting proliferation and maintenance of undifferentiated pSSCs for short-term. For these, undifferentiated pSSCs were progressively cultured in different composition of culture medium, seeding density of pSSCs, type of feeder cells and concentration of growth factors, and then total number of and alkaline phosphatase (AP) activity of pSSCs were investigated at post-6 day culture. As the results, the culture of $4{\times}10^5$ pSSCs on mitotically in activated $2{\times}10^5$ STO cells in the mouse embryonic stem cell culture medium (mESCCM) supplemented with 30 ng/ml glial cell line-derived neurotrophic factor (GDNF) was identified as the best niche condition supporting effectively the short-term maintenance of undifferentiated pSSCs. Moreover, the optimized short-term culture system will be a basis for developing long-term culture system of pSSCs in the following researches.
The Bioconcentration factor(BCF) is used as an important criterion in the risk assessment of environmental contaminants. Also it can be used as indicator of biomagnification of environmentally hazardous chemicals through food-chain as well as a tool for ranking the bioconcentration potential of the chemicals in the environment. This paper reports the measured BCF value on carbofuran in Carassius auratus(goldfish), under steady state, and examined corelation between the BCF value and the depuration rate constant. Carassius auratus(goldfish) was chosen as test organism and test periods were 1-day, 3-day and 5-day. Experimental concentrations were 0.05, 0.10 and 0.50 ppm. Carbofuran in fish tissue and in test water was extracted with n-hexane and acetonitril. GC-ECD was used to detect and quantitate carbofuran. The depuration rate of carbofuran from the whole body of goldfish is determined over the 24-h period after treatment. The obtained results were as follows: 1. It was possible to determine short term BCFs of carbofuran through relatively simple procedure in environmental concentrations. 2. $BCF_1$ of carbofuran in concentration of 0.05, 0.10 and 0.50 ppm were 1.66, 1.64 0.61, $BCF_3$ were 2.08, 2.14, 0.66 and $BCF_5$ were 2.21, 2.57, 0.86, respectively. 3. Carbofuran concentration in fish extract was increased as increasing test concentration and prolonging test period, but $BCF_s$ in concentration of 0.50 ppm was greately decreased. 4. Determined deputation rate constants of carbofuran in concentration of 0.05, 0.10, 0.50 ppm were 0.076, 0.082 and 0.089, respectively. 5. It is considered that great decrease of $BCF_s$ in concentration of 0.50 ppm is due to high water solubility and stability of carbofuran in testwater. 6. It is suggested that low BCF of carbofuran is due to its relatively high water solubility and depuration rate, compared to BPMC, carbaryl and chlorothalonil.
Kim, Seung-Yeon;Lee, Sang-Deok;Kim, Deok-Rae;Lee, Jae-Bum;Song, Chang-Keun;Choi, Kwang-Ho;Han, Jin-Seok
Journal of Korean Society for Atmospheric Environment
/
v.30
no.5
/
pp.423-433
/
2014
This study examined the short-term variability of $CO_2$ concentrations measured at the Gosan site ($33^{\circ}17^{\prime}N$, $126^{\circ}10^{\prime}E$) in Jeju, Korea for the last 9 years from 2002 to 2010. The weekly distribution shows higher $CO_2$ concentrations during weekends than weekdays which implies the impact of local emissions because Jeju Island is one of the top tourist attraction in Korea. In diurnal variation, $CO_2$ concentration reached the maximum at 6 am and the minimum at 1 pm. The high $CO_2$ concentrations were mostly associated with lower wind speed (below 4 m/s) and easterlies, which was typical of summer night. In other seasons, however, the high concentrations were encountered under strong westerlies (8~16 m/s), which implies the influence of Chinese outflows. $CO_2$ concentrations were found to be highly correlated with meteorological parameters including wind speed, temperature, humidity, and solar radiation except for winter.
본 웹사이트에 게시된 이메일 주소가 전자우편 수집 프로그램이나
그 밖의 기술적 장치를 이용하여 무단으로 수집되는 것을 거부하며,
이를 위반시 정보통신망법에 의해 형사 처벌됨을 유념하시기 바랍니다.
[게시일 2004년 10월 1일]
이용약관
제 1 장 총칙
제 1 조 (목적)
이 이용약관은 KoreaScience 홈페이지(이하 “당 사이트”)에서 제공하는 인터넷 서비스(이하 '서비스')의 가입조건 및 이용에 관한 제반 사항과 기타 필요한 사항을 구체적으로 규정함을 목적으로 합니다.
제 2 조 (용어의 정의)
① "이용자"라 함은 당 사이트에 접속하여 이 약관에 따라 당 사이트가 제공하는 서비스를 받는 회원 및 비회원을
말합니다.
② "회원"이라 함은 서비스를 이용하기 위하여 당 사이트에 개인정보를 제공하여 아이디(ID)와 비밀번호를 부여
받은 자를 말합니다.
③ "회원 아이디(ID)"라 함은 회원의 식별 및 서비스 이용을 위하여 자신이 선정한 문자 및 숫자의 조합을
말합니다.
④ "비밀번호(패스워드)"라 함은 회원이 자신의 비밀보호를 위하여 선정한 문자 및 숫자의 조합을 말합니다.
제 3 조 (이용약관의 효력 및 변경)
① 이 약관은 당 사이트에 게시하거나 기타의 방법으로 회원에게 공지함으로써 효력이 발생합니다.
② 당 사이트는 이 약관을 개정할 경우에 적용일자 및 개정사유를 명시하여 현행 약관과 함께 당 사이트의
초기화면에 그 적용일자 7일 이전부터 적용일자 전일까지 공지합니다. 다만, 회원에게 불리하게 약관내용을
변경하는 경우에는 최소한 30일 이상의 사전 유예기간을 두고 공지합니다. 이 경우 당 사이트는 개정 전
내용과 개정 후 내용을 명확하게 비교하여 이용자가 알기 쉽도록 표시합니다.
제 4 조(약관 외 준칙)
① 이 약관은 당 사이트가 제공하는 서비스에 관한 이용안내와 함께 적용됩니다.
② 이 약관에 명시되지 아니한 사항은 관계법령의 규정이 적용됩니다.
제 2 장 이용계약의 체결
제 5 조 (이용계약의 성립 등)
① 이용계약은 이용고객이 당 사이트가 정한 약관에 「동의합니다」를 선택하고, 당 사이트가 정한
온라인신청양식을 작성하여 서비스 이용을 신청한 후, 당 사이트가 이를 승낙함으로써 성립합니다.
② 제1항의 승낙은 당 사이트가 제공하는 과학기술정보검색, 맞춤정보, 서지정보 등 다른 서비스의 이용승낙을
포함합니다.
제 6 조 (회원가입)
서비스를 이용하고자 하는 고객은 당 사이트에서 정한 회원가입양식에 개인정보를 기재하여 가입을 하여야 합니다.
제 7 조 (개인정보의 보호 및 사용)
당 사이트는 관계법령이 정하는 바에 따라 회원 등록정보를 포함한 회원의 개인정보를 보호하기 위해 노력합니다. 회원 개인정보의 보호 및 사용에 대해서는 관련법령 및 당 사이트의 개인정보 보호정책이 적용됩니다.
제 8 조 (이용 신청의 승낙과 제한)
① 당 사이트는 제6조의 규정에 의한 이용신청고객에 대하여 서비스 이용을 승낙합니다.
② 당 사이트는 아래사항에 해당하는 경우에 대해서 승낙하지 아니 합니다.
- 이용계약 신청서의 내용을 허위로 기재한 경우
- 기타 규정한 제반사항을 위반하며 신청하는 경우
제 9 조 (회원 ID 부여 및 변경 등)
① 당 사이트는 이용고객에 대하여 약관에 정하는 바에 따라 자신이 선정한 회원 ID를 부여합니다.
② 회원 ID는 원칙적으로 변경이 불가하며 부득이한 사유로 인하여 변경 하고자 하는 경우에는 해당 ID를
해지하고 재가입해야 합니다.
③ 기타 회원 개인정보 관리 및 변경 등에 관한 사항은 서비스별 안내에 정하는 바에 의합니다.
제 3 장 계약 당사자의 의무
제 10 조 (KISTI의 의무)
① 당 사이트는 이용고객이 희망한 서비스 제공 개시일에 특별한 사정이 없는 한 서비스를 이용할 수 있도록
하여야 합니다.
② 당 사이트는 개인정보 보호를 위해 보안시스템을 구축하며 개인정보 보호정책을 공시하고 준수합니다.
③ 당 사이트는 회원으로부터 제기되는 의견이나 불만이 정당하다고 객관적으로 인정될 경우에는 적절한 절차를
거쳐 즉시 처리하여야 합니다. 다만, 즉시 처리가 곤란한 경우는 회원에게 그 사유와 처리일정을 통보하여야
합니다.
제 11 조 (회원의 의무)
① 이용자는 회원가입 신청 또는 회원정보 변경 시 실명으로 모든 사항을 사실에 근거하여 작성하여야 하며,
허위 또는 타인의 정보를 등록할 경우 일체의 권리를 주장할 수 없습니다.
② 당 사이트가 관계법령 및 개인정보 보호정책에 의거하여 그 책임을 지는 경우를 제외하고 회원에게 부여된
ID의 비밀번호 관리소홀, 부정사용에 의하여 발생하는 모든 결과에 대한 책임은 회원에게 있습니다.
③ 회원은 당 사이트 및 제 3자의 지적 재산권을 침해해서는 안 됩니다.
제 4 장 서비스의 이용
제 12 조 (서비스 이용 시간)
① 서비스 이용은 당 사이트의 업무상 또는 기술상 특별한 지장이 없는 한 연중무휴, 1일 24시간 운영을
원칙으로 합니다. 단, 당 사이트는 시스템 정기점검, 증설 및 교체를 위해 당 사이트가 정한 날이나 시간에
서비스를 일시 중단할 수 있으며, 예정되어 있는 작업으로 인한 서비스 일시중단은 당 사이트 홈페이지를
통해 사전에 공지합니다.
② 당 사이트는 서비스를 특정범위로 분할하여 각 범위별로 이용가능시간을 별도로 지정할 수 있습니다. 다만
이 경우 그 내용을 공지합니다.
제 13 조 (홈페이지 저작권)
① NDSL에서 제공하는 모든 저작물의 저작권은 원저작자에게 있으며, KISTI는 복제/배포/전송권을 확보하고
있습니다.
② NDSL에서 제공하는 콘텐츠를 상업적 및 기타 영리목적으로 복제/배포/전송할 경우 사전에 KISTI의 허락을
받아야 합니다.
③ NDSL에서 제공하는 콘텐츠를 보도, 비평, 교육, 연구 등을 위하여 정당한 범위 안에서 공정한 관행에
합치되게 인용할 수 있습니다.
④ NDSL에서 제공하는 콘텐츠를 무단 복제, 전송, 배포 기타 저작권법에 위반되는 방법으로 이용할 경우
저작권법 제136조에 따라 5년 이하의 징역 또는 5천만 원 이하의 벌금에 처해질 수 있습니다.
제 14 조 (유료서비스)
① 당 사이트 및 협력기관이 정한 유료서비스(원문복사 등)는 별도로 정해진 바에 따르며, 변경사항은 시행 전에
당 사이트 홈페이지를 통하여 회원에게 공지합니다.
② 유료서비스를 이용하려는 회원은 정해진 요금체계에 따라 요금을 납부해야 합니다.
제 5 장 계약 해지 및 이용 제한
제 15 조 (계약 해지)
회원이 이용계약을 해지하고자 하는 때에는 [가입해지] 메뉴를 이용해 직접 해지해야 합니다.
제 16 조 (서비스 이용제한)
① 당 사이트는 회원이 서비스 이용내용에 있어서 본 약관 제 11조 내용을 위반하거나, 다음 각 호에 해당하는
경우 서비스 이용을 제한할 수 있습니다.
- 2년 이상 서비스를 이용한 적이 없는 경우
- 기타 정상적인 서비스 운영에 방해가 될 경우
② 상기 이용제한 규정에 따라 서비스를 이용하는 회원에게 서비스 이용에 대하여 별도 공지 없이 서비스 이용의
일시정지, 이용계약 해지 할 수 있습니다.
제 17 조 (전자우편주소 수집 금지)
회원은 전자우편주소 추출기 등을 이용하여 전자우편주소를 수집 또는 제3자에게 제공할 수 없습니다.
제 6 장 손해배상 및 기타사항
제 18 조 (손해배상)
당 사이트는 무료로 제공되는 서비스와 관련하여 회원에게 어떠한 손해가 발생하더라도 당 사이트가 고의 또는 과실로 인한 손해발생을 제외하고는 이에 대하여 책임을 부담하지 아니합니다.
제 19 조 (관할 법원)
서비스 이용으로 발생한 분쟁에 대해 소송이 제기되는 경우 민사 소송법상의 관할 법원에 제기합니다.
[부 칙]
1. (시행일) 이 약관은 2016년 9월 5일부터 적용되며, 종전 약관은 본 약관으로 대체되며, 개정된 약관의 적용일 이전 가입자도 개정된 약관의 적용을 받습니다.