• Journal of Korean Society of Environmental Engineers
• /
• v.39 no.6
• /
• pp.339-347
• /
• 2017

The objectives of this study were to analyze ecological characteristics of fish compositions and estimate the optimal ecological flow using the physical habitat simulation system (PHABSIM) in Wonju stream and Boseong river. We sampled fishes using two gears such as casting net and kicknet to determine fish distribution and also measured flow velocity, water depth, bed material at the point where fish collected. Total number of species and individuals sampled were 20 and 2,104, respectively and dominant species was Zacco platypus (39.7%) and subdominant species was Z. koreanus (RA: 15.8%) in Wonju stream. In Boseong river, collected fishes were 1,638 individuals, 28 species. Dominant and sub-dominant species was Z. platypus (RA: 22.0%) and Microphysogobio yaluensis (RA: 17.2%), respectively. For calculating habitat suitability index (HSI), we selected Z. platypus as representative fish species and analyzed water depth and flow velocity. Water depth and flow velocity were 0.2-0.6 m, 0.1-0.3 m/s, respectively in Wonju stream and 0.3-0.6 m, 0-0.3 m/s, respectively in Boseong river. According to the analysis of ecological flow simulation, optimal flow was 1.1 cms and 0.3 cms in Wonju stream and 0.4cms, 2.2cms in Boseong river at up and down stream respectively. WUA (Weighted Usable Area) was 9.5%, 26.6% in Wonju stream and 34.8%, 53.3% in Boseong river at up and down stream respectively.

• Journal of The Korean Astronomical Society
• /
• v.50 no.3
• /
• pp.61-70
• /
• 2017

We study the angular correlation function of bright ($K_s{\leq}19.5$) Extremely Red Objects (EROs) selected in the Subaru GTO 2$deg^2$ field. By applying the color selection criteria of $R-K_s$ > 5.0, 5.5, and 6.0, we identify 9055, 4270, and 1777 EROs, respectively. The number density is consistent with similar studies on the optical - NIR color selected red galaxies. The angular correlation functions are derived for EROs with different limiting magnitude and different $R-K_s$ color cut. When we assume that the angular correlation function $w({\theta})$ follows a form of a power-law (i.e., $w({\theta})=A{\theta}^{-{\delta}}$), the value of the amplitude A was larger for brighter EROs compared to the fainter EROs. The result suggests that the brighter, thus more massive high-redshift galaxies, are clustered more strongly compared to the less massive galaxies. Assuming that EROs have redshift distribution centered at ~ 1.1 with ${\sigma}_z=0.15$, the spatial correlation length $r_0$ of the EROs estimated from the observed angular correlation function ranges ${\sim}6-10h^{-1}Mpc$. A comparison with the clustering of dark matter halos in numerical simulation suggests that the EROs are located in most massive dark matter halos and could be progenitors of $L_{\ast}$ elliptical galaxies.

• Journal of Biosystems Engineering
• /
• v.33 no.1
• /
• pp.38-44
• /
• 2008

The freight vehicle is mostly used to transport the fruit. Shock and impact generated by the freight vehicle may give serious damage to fruits hence to reduce the fruits damage, the optimum packaging design during transportation by vehicle is required. In order to design the packaging system for fruit transportation optimally, the comprehension of characteristic for vibration and shock acting on vehicles under various road conditions and loading methods is required. This research was performed to analyze the shock characteristics, acceleration level and power spectral density (PSD) of the fruit transportation vehicles under several travel roads and positions. The vibration signal was measured and analyzed at the transportation vehicle operating on the road of three different surface conditions. The maximum acceleration was measured at the rear-end of the vehicle, and the acceleration in the direction of up-and-down (z-axis) was much greater than those in the directions of back-and-forth (x-axis) or right-and-left (y-axis). The peak acceleration in the direction of up-and-down (z-axis) at the vehicle driving on the expressway, the local road paved with concrete, and unpaved local road were 5.3621 G, 8.232 G, and 14.162 G respectively. PSD at 2.44 Hz showed maximum value at all road conditions. The maximum values of PSD on the expressway, a local road paved with concrete, and unpaved local road were 0.0075222 $G^2/Hz$, 0.058655 $G^2/Hz$, and 0.24598 $G^2/Hz$ respectively. The value of PSD decreased with an increase of the vibration frequency of the transportation vehicle. In most cases, the vibration frequency was below 20 Hz during transportation.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.19 no.4
• /
• pp.405-414
• /
• 2001

Plate tectonics is a dominant paradigm in modern geophysics. Because of its geological mechanism, Korea has a possibility of earthquake according to plate motion. Besides the disaster of earthquake grows rapidly, the importance of recognition for earthquake has been emphasized. This study attempts to decide crustal movement parameters with GPS data, analysed baseline after processing data with GIPSY-OASIS II S/W, observed from 6 stations in and around the Korean peninsula, and obtained from selected 11 stations in Korea. As a results, maximum shear strain was $0.04{\mu}/yr$ and the mean azimuth of the maximum compression axes$(A_{z2})$ is estimated as $97.75^{\circ}$ in and around the Korean peninsula. The average rate of the maximum shear strain($({\gamma}_max)$) is $0.17{\mu}/yr$. The mean azimuth of the maximum compression axes$(A_{z2})$ is estimated as $70.25^{\circ}$ in Korea. Such a pattern of strain distribution is harmonious with that of seismic activity in Korea both historically as well as today.

• Journal of Korean Society of Environmental Engineers
• /
• v.28 no.6
• /
• pp.620-625
• /
• 2006

In this investigation, an ICP-DRC/MS method to measure arsenic with ultra-trace concentration without any interference by the compounds such as $^{40}Ar^{35}Cl^+\;and\;^{40}Ca^{35}Cl^+$, which disturb the precise measurement of arsonic was described. Thus, the oxgen was introduced into the dynamic reaction cell as reaction gas and reacted with arsenic ion created in plasma gas, $AsO^+$ was formed and detected with m/z of 91 by ICP-MS. It resulted in better detection limit than the old method with m/z of 75($As^+$). The optimum condition for oxygen supply as the reaction gas was 0.5 mL/min. The analytical features of the method are as follows: detection limit of $0.02{\mu}g/L$, precision(RSD) of 3.4%, and recovery of 96%. Arsenic in the water samples from the tributary streams to the Han River and the main stream of Paldang were analyzed with this method to identify the characteristics in its distribution. The concentration of As ranged from 0.53 to $1.26{\mu}g/L$. We could measure As with very low concentration, less than $1.0{\mu}g/L$, with excellent reproducibility. The method developed is expected to be applied to analyze As of the samples from sea water, food, and domestic and industrial waste water which have high concentration of Cl and/or Ca.

• Korean Journal of Environment and Ecology
• /
• v.29 no.5
• /
• pp.718-728
• /
• 2015

The fish community and inhabiting status of introduced fish were surveyed at nine stations of Gangeungnamdae stream from September 2013 to May 2014. A total of 36 species of fourteen families were collected from the survey stations and among them, Pungitius sinensis was identified as endangered species. There were nine Korean endemic species (25%) including Coreoleuciscus splendidus. Dominant species were Rhynchocypris steindachneri (St. 1), Zacco koreanus (St. 2, 4, 5, 6), Ladislabia taczanowskii (St. 3)), Zacco platypus (St. 7, 8) and Tribolodon hakonensis (St. 9). Of the 11 introduced species fishes in Gangeungnamdae stream, L. taczanowskii, Pungtungia herzi, Coreoleuciscus splendidus, Squalidus gracilis majimae, Pseudogobio esocinus, Rhynchocypris kumgangensis, Z. platypus, Z. koreanus, Koreocobitis rotundicaudata, Liobagrus andersoni and Coreoperca herzi were released from Han river water zone in Korean. Rapidly expanded population and distribution of introduces fishes were Z. platypus, Z. koreanus, P. herzi and S. gracilis majimae, but L. taczanowskii, C. splendidus, R. kumgangensis were not rapidly expanded population. Settlement but very small population fishes were C. herzi and L. andersoni. When reduced 3% fishes of relative abundance with previous data (1973), R. steindachneri, Orthrias toni, Iksookimia pacifica, Plecoglossus altivelis, P. sinensis and Gymnogobius urotaenia, and R. steindachneri was most reduced from 56.1% to 12.9%.

• Journal of Korean Medicine Rehabilitation
• /
• v.15 no.2
• /
• pp.141-154
• /
• 2005

Objectives : This study was planned to evaluate clinical status of the alopecia patients who had visited oriental medicine clinic. Methods : 80 patients with alopecia, who had visited oriental medicine clinic from January 2004 to August 2004, were examined. Results & Conclusions : 1. The kinds and incidences of Alopecia : androgenetic alopecia 57.5%(46/80), alopecia areatea 20.0%(16/80), telogen effluvium 16.3%(13/80), seborrheic alopecia 6.3%(5/80). 2. In distribution of sex, the rate of male to female was 1:1 and most patients belonged to 20-30 year old group. 3. The most common onset of age was adolescence(63.8%) and the most common duration of hair loss was 1 to 3 years. 4. Among the 30 male androgenetic alopecia patients, Hamilton's type 4 was most common and among the 16 female androgenetic alopecia patients, Ludwig's type II and III were most common. 5. Family history of baldness in Androgenetic alopecia and alopecia areata were 56.5% and 25.0%, respectively. 6. Self-conscious causes of hair loss : stress(48.8%), irregular eating habits(21.3%), and lack of sleep(20.0%). 7. Associated diseases with alopecia patients : chronic neck pain(58.8%), temporomandibular disorders(55.0%) and seborrheic dermatitis(20.0%). 8. Associated symptoms with alopecia Patients : stress(78.8%), sleep disorders(68.8%), irregular eating habits(55.0%), Hot flush(43.8%), Stool disorders(43.8%), cold hands and feet(37.5%) and menstruation disorders(31.3%). 9. The most common scalp type was oily scalp(70.0%) and the symptoms of scalp were iching, dandruff, pain, inflammation. 10. $Bi{\grave{a}}n$ $zh{\grave{e}}ng$(辨證) of alopecia patients : $xu{\grave{e}}-r{\grave{e}}-f{\bar{e}}ng-z{\grave{a}}u$(血熱風燥) (25.0%), $g{\bar{a}}n-sh{\grave{e}}n-b{\grave{u}}-z{\acute{u}}$(肝腎不足) (23.8%), $shi-r{\grave{e}}-sh{\grave{a}}ng-zh{\bar{e}}ng$(濕熱上蒸) (16.3%), $xu{\grave{e}}-r{\grave{e}}-sh{\bar{e}}ng-f{\bar{e}}ng$(血熱生風) (13.8%), $xu{\grave{e}}-x{\bar{u}}-f{\bar{e}}ng-z{\grave{a}}u$(血熱風燥) (13.8%), $y{\bar{u}}-xu{\grave{e}}-z{\check{u}}-lu{\grave{o}}$(瘀血阻絡) (7.5%).

• Journal of Pharmaceutical Investigation
• /
• v.33 no.3
• /
• pp.195-199
• /
• 2003

The objective of this study is to investigate the pharamacokinetic parameters of decursinol following oral administration in Sprague-Dawley rats. The plasma concentration of decursinol was determined by LC/MS with APCI positive mode. The m/z value of decursinol was observed at 247. Following oral administration of decursinol extract, the apparent clearance was $5.3{\pm}2.7\;ml/hr/rat$, the absorption half life was $2.5{\pm}0.41\;hr$, the elimination half life was $3.05{\pm}1.57\;hr$, and the apparent volume of distribution was $21{\pm}12\;ml/rat$. The LC/MS method was successfully applied to the pharmacokinetic study of decursinol.

• Journal of the Korean Institute of Telematics and Electronics D
• /
• v.35D no.1
• /
• pp.8-15
• /
• 1998

An analysis of the microstripline is started as an assumption of the axial & transveral current distribution. Applying the boundary conditions to the scalar wave equations of a electric & magnetic potential, the two simultaneous coupled integral equations are produced. The electronmagnetic fields in microstrip line can be obtained by solving these two coupled integral equaltion. In general, either a numerical analysis method or a Galerkin method was used to solve them. In this paper, a residue theorem is proposed to solve them. The electromagnetic fields are expressed as integral equations for LSE and LSM mode in the spectral domain. Applying a residue theorem to the Fourier transformed equation and Fourier inverse transformed equation which is necessary for interchanging the space domain and the spectral domain, the electromagnetic fields are expressed as algebraic equations whichare relatively easier to handle. the distributions of the electromagnetic field are shown at the range of -5w/2.leq.x.leq.5w/2, 0.lep.y.leq.4h for z=0. It agrees well with the results of the Quasi-TEM mode analysis.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.529-530
• /
• 2011

10본의 선재로 각각 구성되는 내층과 외층을 지니는 2층 원��형 도체를 제작하여 그에 대한 교류손실을 측정하기 위하여, 각 층에 전압리드(inner-lead, outer-lead)들을 부착하였으며, 이로부터 픽업된 층 전압과 층 전류로부터 각 층의 손실을 평가하였다. 그 결과를 요약하면, 외층 전류가 내층의 1/2임에도 불구하고 내 외층의 손실은 거의 일치하였다. 또한 내 외층의 전류가 일치한 경우에도 외층 손실은 내층보다 대단히 크다. 이들 결과는 외층은 내층 전류로부터 발생되는 외부 자장하에 있어 외층의 자장이 증가된 것으로 사료된다.