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Converting Ieodo Ocean Research Station Wind Speed Observations to Reference Height Data for Real-Time Operational Use (이어도 해양과학기지 풍속 자료의 실시간 운용을 위한 기준 고도 변환 과정)

  • BYUN, DO-SEONG;KIM, HYOWON;LEE, JOOYOUNG;LEE, EUNIL;PARK, KYUNG-AE;WOO, HYE-JIN
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.23 no.4
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    • pp.153-178
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    • 2018
  • Most operational uses of wind speed data require measurements at, or estimates generated for, the reference height of 10 m above mean sea level (AMSL). On the Ieodo Ocean Research Station (IORS), wind speed is measured by instruments installed on the lighthouse tower of the roof deck at 42.3 m AMSL. This preliminary study indicates how these data can best be converted into synthetic 10 m wind speed data for operational uses via the Korea Hydrographic and Oceanographic Agency (KHOA) website. We tested three well-known conventional empirical neutral wind profile formulas (a power law (PL); a drag coefficient based logarithmic law (DCLL); and a roughness height based logarithmic law (RHLL)), and compared their results to those generated using a well-known, highly tested and validated logarithmic model (LMS) with a stability function (${\psi}_{\nu}$), to assess the potential use of each method for accurately synthesizing reference level wind speeds. From these experiments, we conclude that the reliable LMS technique and the RHLL technique are both useful for generating reference wind speed data from IORS observations, since these methods produced very similar results: comparisons between the RHLL and the LMS results showed relatively small bias values ($-0.001m\;s^{-1}$) and Root Mean Square Deviations (RMSD, $0.122m\;s^{-1}$). We also compared the synthetic wind speed data generated using each of the four neutral wind profile formulas under examination with Advanced SCATterometer (ASCAT) data. Comparisons revealed that the 'LMS without ${\psi}_{\nu}^{\prime}$ produced the best results, with only $0.191m\;s^{-1}$ of bias and $1.111m\;s^{-1}$ of RMSD. As well as comparing these four different approaches, we also explored potential refinements that could be applied within or through each approach. Firstly, we tested the effect of tidal variations in sea level height on wind speed calculations, through comparison of results generated with and without the adjustment of sea level heights for tidal effects. Tidal adjustment of the sea levels used in reference wind speed calculations resulted in remarkably small bias (<$0.0001m\;s^{-1}$) and RMSD (<$0.012m\;s^{-1}$) values when compared to calculations performed without adjustment, indicating that this tidal effect can be ignored for the purposes of IORS reference wind speed estimates. We also estimated surface roughness heights ($z_0$) based on RHLL and LMS calculations in order to explore the best parameterization of this factor, with results leading to our recommendation of a new $z_0$ parameterization derived from observed wind speed data. Lastly, we suggest the necessity of including a suitable, experimentally derived, surface drag coefficient and $z_0$ formulas within conventional wind profile formulas for situations characterized by strong wind (${\geq}33m\;s^{-1}$) conditions, since without this inclusion the wind adjustment approaches used in this study are only optimal for wind speeds ${\leq}25m\;s^{-1}$.

A Study on the Dietary Quality Assessment among the Elderly in Jeonju Area (전주지역 노인의 식사의 질 평가에 관한 연구)

  • 김인숙;유현희;서은숙;서은아;이형자
    • Journal of Nutrition and Health
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    • v.35 no.3
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    • pp.352-367
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    • 2002
  • In order to assess the quality of dietary intake among the elderly, a survey was conducted during Jucy-August, 1999, of 230 subjects who were 65 years or older and who were living in Jeonju City. Results of the analysis of the data are as follows : Regarding Dietery Variety Score (DVS), the average number of food items consumed per person was significantly higher for males (19.6) than for females (17.7). The intake of plant food was higher than animal food for both sexes the proportion of plant versus animal foods consumed by fresh weight was 85 : 15 for males and 89 : 11 for females. Diet Diversity Score (DDS) is determined by how many from five food groups (cereal, meat, dairy, vegetable and fruit) consumed per day while Korean Diet Diversity Score (KDDS) is determined by how many from five different food groups (cereal, meat, vegetable, dairy and oil) consumed per day. The subjects'average DDS and KDDS were 4.0 and 3.5 for males, and 3.7 and 3.2 for females, respectively. Overall, the distribution of DDS was lower than that of KDDS. The average Meal Balance Score (MBS : Apply the KDDS at breakfast, lunch and dinner) was 9.1 for malts and 8.1 for females. Average daily caloric intake for males and females was 1,740 kcal and 1,433 kcal, which was 84.0% and 80.9% of the RDA, respectively. Average daily protein intake for males and females, at 67 g and 49 g (100.7% and 88.3% of the RDA), respectively, was satisfactory. However, intakes of calcium and vitamin A were below 75% of the RDA (calcium : 62.7% for males and 55.3% for females ; vitamin A : 60.7% for males and 53.9% far females). The average proportional contribution of protein/fat/carbohydrate (PFC) to total calorie intake was 15.8 : 15.7 : 68.5 for males and 13.8 : 13.2 : 73.0 for females. Distribution of energy for each meal (breakfast : lunch : afternoon snack : dinner : night snack) was 29.2 : 32.4 : 5.0 : 31.2 : 2.2 among males and 30.5 : 33.5 : 4.5 : 28.6 : 2.91 among females. The Index of Nutritional Quality (INQ) was above 1 for protein, phosphorus, iron, vitamin B$_1$, niacin, and vitamin C. However, the INQ of calcium and vitamin A were below 1 among both males and females, and the INQ of vitamin B$_2$was below l among females. The Nutrient Adequacy Ratio (NAR = nutrient intake %RDA) was below 1 for all nutrients, and the NAR of vitamin A were the lowest among 9 nutrients (protein, calcium, phosphorus, iron, vitamin A, vitamin B$_1$, vitamin B$_2$, niacin, vitamin C) for both males and females, with values of 0.52 and 0.42, respectively. The second and third lowest NAR values were for calcium(males: 0.68: females: 0.54) and vitamin B$_2$(males: 0.77: females: 0.67). Values of Mean Adequacy Ratio (MAR = sum of 9 NARs/9) for males (0.82) were higher than for females (0.73). These results indicate that the intakes of calcium and vitamin A were severely inadequate. The results of a stepwise multiple regression analysis, where the DVS or MAR were the dependent variables and the DDS, KDDS, and MBS were independent variables, indicated that DDS is a more useful variable than KDDS in determining the quality of meals of the elderly.

Modeling of Estimating Soil Moisture, Evapotranspiration and Yield of Chinese Cabbages from Meteorological Data at Different Growth Stages (기상자료(氣象資料)에 의(依)한 배추 생육시기별(生育時期別) 토양수분(土壤水分), 증발산량(蒸發散量) 및 수량(收量)의 추정모형(推定模型))

  • Im, Jeong-Nam;Yoo, Soon-Ho
    • Korean Journal of Soil Science and Fertilizer
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    • v.21 no.4
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    • pp.386-408
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    • 1988
  • A study was conducted to develop a model for estimating evapotranspiration and yield of Chinese cabbages from meteorological factors from 1981 to 1986 in Suweon, Korea. Lysimeters with water table maintained at 50cm depth were used to measure the potential evapotranspiration and the maximum evapotranspiration in situ. The actual evapotranspiration and the yield were measured in the field plots irrigated with different soil moisture regimes of -0.2, -0.5, and -1.0 bars, respectively. The soil water content throughout the profile was monitored by a neutron moisture depth gauge and the soil water potentials were measured using gypsum block and tensiometer. The fresh weight of Chinese cabbages at harvest was measured as yield. The data collected in situ were analyzed to obtain parameters related to modeling. The results were summarized as followings: 1. The 5-year mean of potential evapotranspiration (PET) gradually increased from 2.38 mm/day in early April to 3.98 mm/day in mid-June, and thereafter, decreased to 1.06 mm/day in mid-November. The estimated PET by Penman, Radiation or Blanney-Criddle methods were overestimated in comparison with the measured PET, while those by Pan-evaporation method were underestimated. The correlation between the estimated and the measured PET, however, showed high significance except for July and August by Blanney-Criddle method, which implied that the coefficients should be adjusted to the Korean conditions. 2. The meteorological factors which showed hgih correlation with the measured PET were temperature, vapour pressure deficit, sunshine hours, solar radiation and pan-evaporation. Several multiple regression equations using meteorological factors were formulated to estimate PET. The equation with pan-evaporation (Eo) was the simplest but highly accurate. PET = 0.712 + 0.705Eo 3. The crop coefficient of Chinese cabbages (Kc), the ratio of the maximum evapotranspiration (ETm) to PET, ranged from 0.5 to 0.7 at early growth stage and from 0.9 to 1.2 at mid and late growth stages. The regression equation with respect to the growth progress degree (G), ranging from 0.0 at transplanting day to 1.0 at the harvesting day, were: $$Kc=0.598+0.959G-0.501G^2$$ for spring cabbages $$Kc=0.402+1.887G-1.432G^2$$ for autumn cabbages 4. The soil factor (Kf), the ratio of the actual evapotranspiration to the maximum evapotranspiration, showed 1.0 when the available soil water fraction (f) was higher than a threshold value (fp) and decreased linearly with decreasing f below fp. The relationships were: Kf=1.0 for $$f{\geq}fp$$ Kf=a+bf for f$$I{\leq}Esm$$ Es = Esm for I > Esm 6. The model for estimating actual evapotranspiration (ETa) was based on the water balance neglecting capillary rise as: ETa=PET. Kc. Kf+Es 7. The model for estimating relative yield (Y/Ym) was selected among the regression equations with the measured ETa as: Y/Ym=a+bln(ETa) The coefficients and b were 0.07 and 0.73 for spring Chinese cabbages and 0.37 and 0.66 for autumn Chinese cabbages, respectively. 8. The estimated ETa and Y/Ym were compared with the measured values to verify the model established above. The estimated ETa showed disparities within 0.29mm/day for spring Chinese cabbages and 0.19mm/day for autumn Chinese cabbages. The average deviation of the estimated relative yield were 0.14 and 0.09, respectively. 9. The deviations between the estimated values by the model and the actual values obtained from three cropping field experiments after the completion of the model calibration were within reasonable confidence range. Therefore, this model was validated to be used in practical purpose.

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Studies on the Nitrogenous Utilization and Basal Metabolism of Korean Native Goat (한국(韓國) 재래산양(在來山羊)의 질소대사(窒素代謝) 및 기초대사량(基礎代謝量)에 관(關)한 연구(硏究))

  • Oh, Hong Rock
    • Korean Journal of Agricultural Science
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    • v.9 no.2
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    • pp.546-555
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    • 1982
  • To evaluate the digestibility and absorbability of proteins, and the rates of energy and nitrogen(N) metabolism of the Korean native goats, studies were carried out with open type respiration apparatus based on the nitrogen-carbon method. The results on the nitrogen retention and the metabolic rate of energy, which was obtained with one male (10-month-old) and one female (24-month-old) goats, both weighing ${\simeq}20kg$, are summarized as follows. 1. When the goats were fed ad libitum the medium quality orchard grass hay, they consumed hay about 0.66 to 0.92% of body weight per day. The hay intake was remained the same even when high quality hay was provided. This amount of hay intake was relatively lower than that of dairy goat and sheep. It was believed to be partly due to the change in feeding enviroment. When fed with hay and soybean meal together, the goats ate hay about 1.06% and soybean meal about 0.60% of body weight, corresponding to 1.66% of body weight as fed basis. 2. The $CO_2$ gas produced from the goat in the open type respiration chamber and absorbed with KOH solution was estimated to be 99~117g/day. The difference in feed intake did not influence the $CO_2$ production; however, these seems to be a linea relationship between body weight and $CO_2$ production. 3. When fed orchard grass hay only, the goats showed protein digestibility of 24~41%. The protein digestibility incresed to 58.2% when fed hay and soybean meal together. A negative nitrogen balance(-0.16g N/day) was observed with goats fed 11.53g N originated from 212g hay and 150g soybean meal. Converting that nitrogen ingested to a crude protein, the amount of crude protein intake by the goats per day was 77.9g compared to 40~45g N known to be required in a day by goat weighing 20kg, indicating that the extra protein ingested was metabolized to provide energy. 4. When the male and female goats comsumed 624 kcal gross energy and 824 kcal gross energy by consuming 158g and 213g of hay, respectively, the digestible energy intake was calculated to be 260kcal for the male and 199kcal for the female goat. The daily heat production of male and female goats were 338kcal and 334kcal, respectively, when fed hay only. However, the female goat fed 212g hay and 150g soybean meal produced about 591kcal per day. Consequently, the energy requirment of the Korean native goats weighing ${\simeq}20kg$ was concluded to be $${\geq_-}$$600kcal net energy per day. 5. The fasting heat product ion of a male goat weighing 27.7kg was 412kcal per day when fasted for 2~3 days. When fasted for 3~4 days, the value decresed to 240kcal. The enviromental temperatures during the expreimental period were ranged from 19 to $34.5^{\circ}C$. The goats seemed to be panting when the chamber temperature rose to $32^{\circ}C$ or above. 6. When fed low levels of dietary protein, serum protein levels of the goats were decresed slightly ($${\leq_-}$$10%); however, urea content in the serum was observed to decrese to a great extent (3X).

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A Study on Serum Lipid Levels in Elderly People in Wando Area - Based on Age, BMI, WHR - (완도지역 성인 및 노인의 혈청지질 수준에 관한 연구(I) - 연령, 신체 계측치를 중심으로 -)

  • Cha, Bok-Kyeong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.1
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    • pp.68-77
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    • 2006
  • This study was peformed to document the association between nutrient intakes, body mass index (BMI), waist/hip ratio (WHR), and a major risk factor for chronic diseases. A three-day dietary intake survey, using a 24 hour recall method, was obtained from 187 subjects aged 46 to 84 (mean age 65.3) living in Wando island area. The average daily mean energy intakes were 1869.0 kcal for male and 1943.9 kcal for female, respectively. Daily intakes of protein for male and female were 28.0 and 30.4 g, and those of fat were 31.5 and 28.51 g, respectively Carbohydrate dependency was decreased with age. Protein dependency was increased with age. The mean intakes of energy, protein, Vit. A, Vit. D, Vit. E, Ca, Zn did not meet Korean RDA for elderly. The level of serum triglyceride was higher in males than in females and showed the tendency to increase with age in both sexes, whereas HDL-cholesterol tended to decrease with age in both sexes. The levels of serum total-cholesterol and LDL-cholesterol were significantly higher in males than in females, particularly in the age of $46\~59$ (p<0.05). The level of atherogenic index (AI) was significantly higher in females than in males, particularly in the age of 80 and over (p<0.05) Based on these results, it is evident that people in island area did not consume enough nutrient. Specially, dietary intake of protein was not adequate. This study implies that triglyceride, total-cholesterol, LDL-cholesterol, AI were increased with increasing age, BMI and WHR.