• Title/Summary/Keyword: Discharge Time

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Neuroendocrine Control of Gonadotropin Secretion during the Menstrual Cycle

  • Ryu, Kyung-Za
    • The Korean Journal of Pharmacology
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    • v.23 no.2
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    • pp.57-75
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    • 1987
  • Two modalities of gonadotropin secretion, pulsatile gonadotropin and preovulatory gonadotropin surge, have been identified in the mammals. Pulsatile gonadotropin secretion is modulated by the pulsatile pattern of GnRH release and complex ovarian steroid feedback actions. The neural mechansim that regulates the pulsatile release of GnRH in the hypothalamus is called "GnRH pulse generator". Ovarian steroids, estradiol and progesterone, appear to exert thier feedback effects both directly on the pituitary to modulate gonadotropin release and on a hypothalamic site to modulate GnRH release; estradiol primarily affects the amplitude while progesterone decreases the frequency of the pulsatile GnRH. Steroid hormones are known to affect catecholamine transmission in brain. MBH-POA is richly innervated by NE systems and close apposition of NE terminals and GnRH cell bodies occurs in the MBH as well as in the POA. NE normally facilitates pulsatile LH release by acting through ${\alpha}-receptor$ mechanism. However, precise nature of facilitative role of NE transmission in maintaining pulsatile LH has not been clearly understood. Close apposition of DA and GnRH terminals in ME might permit DA to influence GnRH release. Action of DA transmission probably is mediated by axo-axonic contacts between GnRH and DA fibers in the ME. Dopamine transmission does not normally regulate pulsatile LH release, but under certain conditions, increased DA transmission inhibit LH pulse. Endogenous opioid acts to suppress the secretion of GnRH into hypophysial portal circulation, thereby inhibiting gonadotropin secretion. However, an interaction between endogenenous opioid peptides and gonadotropin release is a complex one which involves ovarian hormones as well. LH secretion appears to be most suppressed by endogenenous opioids during the luteal phase, at a time of elevated progesterone secretion. The arcuate nucleus contains not only cell bodies for GnRH and ${\beta}-endorphin$ but also a dense aborization of fibers suggesting that GnRH release is changed by the interactions between GnRH and ${\beta}-endorphin$ cell bodies within the arcuate nucleus. The frequency and amplitude of pulsatile LH release seem to be increased during the preovulatory gonadotropin surge. Estradiol exerts positive feedback action on the hypothalamo-pituitary axis to trigger preovulatory LH surge. GnRH is also crucial hormonal stimulus for preovulatory LH surge. It is unlikely, however, that increased secretion of GnRH during the preovulatory gonadotropin surge represents an obligatory neural signal for generation of the LH discharge in primates including human. Modulation of preovulatory LH surge by catecholamines has been studied almost exclusively in rats. NE and E may be involved in distinct way to accumulate GnRH in the MBH and its release into the hypophysial portal system during the critical period for LH surge on proestrus in rats. However, the mechanisms whereby augmented adrenergic transmission may facilitate the formation and accumulation of GnRH in the ME-ARC nerve terminals before the LH surge have not been clearly understood.

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A Cause Analysis of Missed Fractures in an Emergency Medical Center (응급센터에 내원한 외상환자에서 간과된 골절의 요인 분석)

  • Park, Deuk-Hyun;Lee, Sung-Sil;Kim, Dong-Un;Cho, Hyun-Young;Lee, Young-Geun;Kim, Jun-Su;Jun, Jin;Kim, Young-Sik;Ha, Young-Rock;Sin, Tae-Yong
    • Journal of Trauma and Injury
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    • v.22 no.1
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    • pp.37-43
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    • 2009
  • Purpose: A missed fracture is a very common occurrence in the Emergency Department (ED) and can have serious results because of delays in treatment, resulting in long-term disability. It is also one of the most common causes leading to medical legal issues. We analyzed the causes of missed fractures by using a bone scan which is known to be an effective tool for diagnosing bony lesions. Methods: We reviewed the medical records of trauma patients who underwent a bone scan after being discharged the ED from September 2006 to March 2008. Cases of missed fractures were identified by using electronic medical records to review each diagnosis. Definition of missed fracture was read after bone scan by radiologist. We decided that there was no fracture if we read 'trauma-related lesion' or 'cannot rule out fracture' on a bone scan read by a radiologist. Enrolled patients were analyzed by age, sex, time until bone scan and Injury Severity Score (ISS). Patients were divided into two groups, alert mentality and not-alert mentality, so there were split between a diagnosis group and a missed fracture group. ISS was also used in determining the severity of the patient's injury upon discharge from the ED. Results: A total of 532 patients were enrolled in this study. Of those, 487 patients were in the diagnosis group, and 45 patients (8.4%) were discovered to have had a fracture. Of the 45 missed fracture patients, 34 patients (6.4%) had one-site fractures, 8 patients (1.5%) had two-site fractures, and 3 patients (0.6%) had three-site fractures. The most commonly missed fracture was multiple rib fractures (18 patients, 30.5%), followed by lumbosacral (LS) spine fractures (10 patients, 16.9%), thoracic spine fractures (8 patients, 13.6%), and clavicle fractures (6 patients, 10.2%). Mean age was $50.12{\pm}18.54$ years in the diagnosis group and $57.38{\pm}16.88$ years in the missed fracture group. For the diagnosis group, the mean ISS was $9.03{\pm}8.26$, but in the missed fracture group it was $17.53{\pm}9.69$. Missed fractures were much more frequent in the not-alert mentality (p<0.01) and in the high (ISS$ ISS{\geq}16$) group (p<0.01). Conclusion: Missed fractures occur most frequent in patients of old age, not-alert mentality, and high ISS. Multiple rib and spine fractures were found to be the most frequent missed fractures, regardless of trauma severity. This study also shows a high possibility of clavicle and scapula fractures in patients with severe trauma.

Two Cases of Invasive Pseudomonas aeruginosa Infection that Developed in the Apparently Immunocompetent Infants (면역 기능의 이상이 발견되지 않은 영아에서의 침습성 녹농균 감염증 2례)

  • Kang, Min Jae;Kim, So Hee;Kim, Nam Hee;Lee, Jin-A;Eun, Byung Wook;Choi, Eun Hwa;Lee, Hoan Jong
    • Pediatric Infection and Vaccine
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    • v.13 no.2
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    • pp.180-185
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    • 2006
  • Invasive Pseudomonas infections most often occur in the immunocompromised patients and are associated with high mortality rate. Rarely this disease may develop in healthy infants and children. We report two cases of invasive Pseudomonas aeruginosa infections that were diagnosed in otherwise healthy infants. The first case was a previously healthy 5-month-old infant with ecthyma gangrenosum and septicemia. She presented with fever, swelling of left periorbital area and multiple erythronodular skin lesions. Each skin lesion formed a black eschar surrounded by an erythematous areola over time. Cultures of blood, urine and discharge from skin lesions grew P. aeruginosa. On the day of visit, she showed pancytopenia which was normalized after 10 days. The patient responded well to the management with ceftazidime and tobramycin. The other case was a previously healthy 9-month-old infant with community-acquired pneumonia. He was referred from an outside hospital with fever and cough. Chest x-ray revealed pneumonic infiltrations on both lower lungs with pleural effusion on the right side. Cultures of blood and pleural fluid grew P. aeruginosa. Chest CT performed on the ninth day demonstrated pneumatoceles, lung abscess and necrosis of lung parenchyma. He was managed with ceftazidime and amikacin for 50 days. No residual pulmonary complications were noted during the three month follow-up. Laboratory results to evaluate immunologic defects of phagocytic cells, complement components and T- and B-lymphocytes were all within normal range in both patients. It should be kept in mind that Pseudomonas can be, though uncommon, a cause of community-acquired invasive infections in the previously healthy infants.

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A Study of Adenovirus Pneumonia: Early Summer Outbreak in 1996 (1996년 초여름에 유행한 Adenovirus폐렴의 검토)

  • Kim, Chang Keun;Chung, Churl Young;Kim, Jung Suk;Lee, Hoan Jong
    • Pediatric Infection and Vaccine
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    • v.3 no.2
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    • pp.145-153
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    • 1996
  • The incidence of Adenovirus(AV) pneumonia in children is estimated at 8%. Long-term complications reported with type 7 include hyperleucent lung syndrome, bronchiolitis obliterans and may require several months to recover. We reviewed 8 case of AV pnemonia confirmed by AV culture and sero-diagnosis among selected 19 AV pneumonia suspicious cases who were admitted to the Sanggye Paik Hospital of Inje University due to clinical pneumonia from May to July 1996. From 19 children, nasal aspirates or trachial aspirates were collected: viral agents were detected by virus isolation and virus antigen was detected by indirect immunofluorescent staining. Serologic diagnosis for type-specific AV antibody was done by neutralisation test. The results are as follows: 1) Age of the patients ranged from 6 months to 47 months with a mean of $24{\pm}9$ months. 6 were male and 2 were female(M:F= 3:1). 2) Monthly distribution showed 4 cases on June, 2 cases on May and July, respectively. 3) The mean duration of admission was 20.4 days and mean duration of fever was 11.3 days 4) Peripheral leukocyte counts were elevated in 4 cases(50%) and findings of shift to left were showed in 4 cases(50%) and serum aminotransferase activities were elevated in 6 case(75%). 5) Radiologic findings include linear and streaky infiltration(1/8 cases), patchy and lobar consolidation (7/8 cases), pleural effusion(2/8 cases) and hyperleucency was seen in 3/8 cases at time of admission and increased to 6/8 cases on hospital discharge. 6) The AV serotypes were type 7, type 3, and type 1. 7) Oxygen supply was done in 4 cases(50%) and all 8 patients include 2 cases of type 7 treated with artificial ventilator were survived. In conclusion, the serotypes of AV pneumonia outbreaks in early summer of 1996 were type 7, 3, 1 and, as showed severe clinical course, continued follow up surveillance is necessary to the long term pulmonary complications.

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Hyoid Bone Fracture Associated with Hypoglossal Nerve Palsy: A Case Report (설하신경마비를 동반한 설골골절: 증례보고)

  • Kim, Sin-Rak;Park, Jin-Hyung;Han, Yea-Sik
    • Archives of Plastic Surgery
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    • v.38 no.2
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    • pp.199-202
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    • 2011
  • Purpose: Hyoid bone is a U-shaped bone in the anterior of the neck. Hyoid bone fractures are exceedingly rare and represent only 0.002% of all fractures because of its protective position relative to the mandible and its suspension by elastic musculature. We report a patient who presented hyoid bone fracture associated with hypoglossal nerve palsy. We also discuss the possible complication and treatment. Methods: A 69-year-old man was transferred from another institution because of persistent purulent discharge from the left chin. He had a history of trauma in which a knuckle crane grabbed his face and neck in the construction site. A CT scan at the time of the accident demonstrated a comminuted fracture of the right side of the mandible and hyoid bone fracture at the junction between body and right greater cornua. The displaced fracture of hyoid bone and fullness in the pre-epiglottic space were noted, probably indicating some edema. The patient was transferred into ICU after treatment of emergency tracheostomy because the patient showed respiratory distress rapidly. When the patient was hospitalized in our emergency room, he complained of dysphagia and pain when swallowing. On examination of oral cavity, the presence of muscle wasting with fasciculation of the tongue was noted and the tongue deviates to the left side on protruding from the mouth. Pharyngolarygoscopy was performed to make sure that there was no evidence of progressive swelling and pharyngeal laceration. Results: The patient underwent surgical removal of dead and infected tissue from the wound and reconstruction of mandibular bony defect by iliac bone grafting. Hyoid bone fracture was managed conservatively with oral analgesics, soft diet and restricted movement. Hypoglossal nerve palsy was resolved within 7 weeks after trauma without complications. Conclusion: Closed hyoid bone fracture is usually uncomplicated and thus it can be treated conservatively. Surgical intervention for hyoid bone fracture is recommended for patient with airway compromise, pharyngeal perforation and painful symptoms which show no response to conservative care. Furthermore, since respiratory distress syndrome may develop quickly, close observation is required. Besides, hypoglossal nerve palsy is a rarely recognized complication of hyoid bone fracture.

An Esitimation of Lognitudinal Dispersion Coefficient in Natural Stram Using Hydraulic Model (수리모형을 이용한 자연하천에서 종확산계수 추정)

  • Yun, Se-Ui;Han, Geon-Yeon;Han, Jeong-Seok;Kim, Jeong-Su
    • Journal of Korea Water Resources Association
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    • v.33 no.4
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    • pp.407-417
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    • 2000
  • To estimate the longitudinal dispersion coefficient at the downstream of Jungrang-River, the undistorted 1/20 scale hydraulic model was used in this study. Experiments were conducted for dry season discharge, and Rhodamine B was used as a tracer. The relationship curve between concentration and conductivity of Rhodamine B was otained by laboratory test, and the conductivity which was measured in hydraulic model was converted to concentration using this curve. The longitudinal dispersion coefficient was calculated using the relationship between the peak concentration and the time to peak concentration. The results of this study were compared with the calculated values by the empirical equations for the longitudinal dispersion coefficient and with the field data. The results of comparison show that Parker's equation underestimates, and Liu'g equation and Iwasa and Aya's one overestimate, and McQuivey and Keefer's equations, Fischer's one, Magazine's one, and Seo and Cheong's one predict relatively well. The measured data sets were relatively close to the observed ones in natural river. The longitudinal dispersion coefficient at the downstream of Jungrang-River was estimated $10\textrm{m}^2/s$.

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A Novel Approach for Controlling Process Uniformity with a Large Area VHF Source for Solar Applications

  • Tanaka, T.
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.08a
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    • pp.146-147
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    • 2011
  • Processing a large area substrate for liquid crystal display (LCD) or solar panel applications in a capacitively coupled plasma (CCP) reactor is becoming increasingly challenging because of the size of the substrate size is no longer negligible compared to the wavelength of the applied radio frequency (RF) power. The situation is even worse when the driving frequency is increased to the Very High Frequency (VHF) range. When the substrate size is still smaller than 1/8 of the wavelength, one can obtain reasonably uniform process results by utilizing with methods such as tailoring the precursor gas distribution by adjustingthrough shower head hole distribution or hole size modification, locally adjusting the distance between the substrate and the electrode, and shaping shower head holes to modulate the hollow cathode effect modifying theand plasma density distribution by shaping shower head holes to adjust the follow cathode effect. At higher frequencies, such as 40 MHz for Gen 8.5 (2.2 m${\times}$2.6 m substrate), these methods are not effective, because the substrate is large enough that first node of the standing wave appears within the substrate. In such a case, the plasma discharge cannot be sustained at the node and results in an extremely non-uniform process. At Applied Materials, we have studied several methods of modifying the standing wave pattern to adjusting improve process non-uniformity for a Gen 8.5 size CCP reactor operating in the VHF range. First, we used magnetic materials (ferrite) to modify wave propagation. We placed ferrite blocks along two opposing edges of the powered electrode. This changes the boundary condition for electro-magnetic waves, and as a result, the standing wave pattern is significantly stretched towards the ferrite lined edges. In conjunction with a phase modulation technique, we have seen improvement in process uniformity. Another method involves feeding 40 MHz from four feed points near the four corners of the electrode. The phase between each feed points are dynamically adjusted to modify the resulting interference pattern, which in turn modulate the plasma distribution in time and affect the process uniformity. We achieved process uniformity of <20% with this method. A third method involves using two frequencies. In this case 40 MHz is used in a supplementary manner to improve the performance of 13 MHz process. Even at 13 MHz, the RF electric field falls off around the corners and edges on a Gen 8.5 substrate. Although, the conventional methods mentioned above improve the uniformity, they have limitations, and they cannot compensate especially as the applied power is increased, which causes the wavelength becomes shorter. 40 MHz is used to overcome such limitations. 13 MHz is applied at the center, and 40 MHz at the four corners. By modulating the interference between the signals from the four feed points, we found that 40 MHz power is preferentially channeled towards the edges and corners. We will discuss an innovative method of controlling 40 MHz to achieve this effect.

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미세금형 가공을 위한 전기화학식각공정의 유한요소 해석 및 실험 결과 비교

  • Ryu, Heon-Yeol;Im, Hyeon-Seung;Jo, Si-Hyeong;Hwang, Byeong-Jun;Lee, Seong-Ho;Park, Jin-Gu
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2012.05a
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    • pp.81.2-81.2
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    • 2012
  • To fabricate a metal mold for injection molding, hot-embossing and imprinting process, mechanical machining, electro discharge machining (EDM), electrochemical machining (ECM), laser process and wet etching ($FeCl_3$ process) have been widely used. However it is hard to get precise structure with these processes. Electrochemical etching has been also employed to fabricate a micro structure in metal mold. A through mask electrochemical micro machining (TMEMM) is one of the electrochemical etching processes which can obtain finely precise structure. In this process, many parameters such as current density, process time, temperature of electrolyte and distance between electrodes should be controlled. Therefore, it is difficult to predict the result because it has low reliability and reproducibility. To improve it, we investigated this process numerically and experimentally. To search the relation between processing parameters and the results, we used finite element simulation and the commercial finite element method (FEM) software ANSYS was used to analyze the electric field. In this study, it was supposed that the anodic dissolution process is predicted depending on the current density which is one of major parameters with finite element method. In experiment, we used stainless steel (SS304) substrate with various sized square and circular array patterns as an anode and copper (Cu) plate as a cathode. A mixture of $H_2SO_4$, $H_3PO_4$ and DIW was used as an electrolyte. After electrochemical etching process, we compared the results of experiment and simulation. As a result, we got the current distribution in the electrolyte and line profile of current density of the patterns from simulation. And etching profile and surface morphologies were characterized by 3D-profiler(${\mu}$-surf, Nanofocus, Germany) and FE-SEM(S-4800, Hitachi, Japan) measurement. From comparison of these data, it was confirmed that current distribution and line profile of the patterns from simulation are similar to surface morphology and etching profile of the sample from the process, respectively. Then we concluded that current density is more concentrated at the edge of pattern and the depth of etched area is proportional to current density.

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A Hydrological Study on the Flow Characteristic of the Keum River (하천의 유황에 관한 수문학적 연구)

  • 박성우
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.16 no.2
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    • pp.3438-3453
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    • 1974
  • Unmeasured value of water for human lives is widely approved, but the water as one of natural resources cannot be evaluated with ease since it changes itself ceaselessly by flowing-out or transforming the phase. Major objectives of the study concerned consequently with investigating its potentiality and evaluating its time seriesly availabity in a volumatic unit. And the study was performed to give the accurate original data to the planners concerned. Some developed rational methods of predicting runoff related to hydrological factors as precipitation, were to be discusseed for their theorical background and to be introduced whether they needed some corrections or not, comparing their estimation with actual runoff from synthetic unit-hydrograph methods. To do so, the study was performed to select Kongju Station, located at the watershed of the Keum River, and to collect such hydrological data from 1962 to 1972 as runoff, water level, precipitation, and so on. On the other hand, the hydrological characteristics of runoff were concluded more reasonably in numerical values, with calculating the the ratio of daily runoff to annual discharge of the flow in percentage, as. the distribution ratio of runoff. The results of the study can be summarized as follows; (1) There needed some consideration to apply the Kajiyama's Formula for predicting monthly runoff of rivers in Korea.(2) The rational methods of predicting runoff might be recommended to become less theorical and reliable than the unique analyzation of data concerned in each given water basin. The results from the Keum River prepared above would be available to any programms concerned. (3) The most accurate estimation for runoff could be suggested to synthetic unithydrograph methods calculated from the relation between each storm and runoff. However it was not contained in the study. (4) The relations between rainfall and runoff at KongJu Station were as following table. The table showed some intersting implications about the characteristics of runoff at site, which indicated that the runoff during three months from July to September approached total of 60% of quantity while precipitation concentrated on the other three from June to August. And there were some months which had more amount of runoff than expected values calculated from the precipitation, such as Febrary, March, August, September, Octover, and December, shown in the table. Such implications should be suggested to meet any correction factors in the future formulation concerned with the subjects, if any rational methods would be required.

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Planning of Extuary Reservoirs for the Development of Water Resources -A Comparative Study of Representation Cases of Korea and Japan- (유역이수의 고도화에 대응하는 하구담수호의 계획론 -한국.일본의 대표적 사례의 비교연구-)

  • 이희영
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.24 no.1
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    • pp.44-52
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    • 1982
  • Recently, estuary reserovoirs have been actively constructed in Korea and also in Japan there are a large number of estuary reservoirs constructed. But most of the estuary reservoirs are located at the downstream of a river where geographical condition is best for the construction of an enclosing dam. And an effective utilization of water from the estuary reservoir seems to be difficult even if estuary reservoirs are considered to be the water resources the most available for their watershed. Studies on estuary reservoirs so far have been mainly concentrated on the physical and engineering problems of the dam construction itself. The purpose of the present study is to review the estuary reservoir planning in connection with the water resources development and to study a basis of the planning. First, the levels of water use in Korea and Japan were compared with those of other countries in the world. And then, some representative reservoirs were selected to study the roles of a reservoir and water-using conditions in the watershed. Based on the study, a survey was given on the relation between a dam construction upstream and an estuary reservoir construction downstream of a river. Finally, a comprehensive examination was made of the bases of estuary reservoir planning. (1) The estuary reservoir planning is deeply related to the plan for water use develo- pment in the watershed. After the upstream water resources were fully developed up to the most, water reso- urces development by an estuary reservoir should be started. (2) If an estuary lake has a capacity big enough, it can store flood discharge of the watershed without any loss and become a basic facility that will bring about the maxi- mum use of water from the watershed. (3) Estuary reservoirs store water used in the upstream watershed, so recycling of water use is attained by the reservoir. Water in the estuary lake is difficult to be fresh water in its long run. Therefore, estuary reservoir should be located at a place where polluted water is purified and refused. All the planning should be based on the assumption that water in the estuary lake is not fresh but polluted after a long time. (4) The estuary lake can only supply water to the lower basin directly. But the upstream area is benefited from the estuary lake by exchange of irrigation water sources between the lower and the upper area. So a large-scale exchange plan between new and existing water resources is important. By constructing estuary reservoirs and the exchange of water sources between upper and lower areas, the reasonable maximum use of water from the whole watershed is at- tained. (5) The big problem coming from the water resources development by an enclosing estuary is salt water intrusion into the lake. To maintain the estuary lake salt-free, multi-purpose use of the lake should be avoided. It is necessary to take such fundamental measures as abolition of back flow operation of gate, and the closing of the fish port and the fish ladder. The results mentioned above were found in this study and these results of this study could be used for the adequate planning of estuary reservoirs in connection with the maximum water use of the watershed.

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