강변저류지가 있는 하도에서의 부정류 흐름 모의를 위한 HEC-RAS의 적용성 검토

김서준,홍상진,윤병만,지운,Kim, Seo-Jun,Hong, Sang-Jin,Yoon, Byung-Man,Ji, Un 한국수자원학회 2012 한국수자원학회논문집 Vol.45 No.5

하천에 설치되는 강변저류지의 효율적 설계를 위해서는 정확한 부정류 흐름 해석이 반드시 필요하다. 일반적으로 하천의 부정류 수치모의는 1차원 부정류 수치모형인 HEC-RAS를 많이 사용하고 있다. 하지만 강변저류지가 있는 하도에서의 부정류 흐름에 대한 수리실험과 현장 모니터링 자료가 거의 없기 때문에 HEC-RAS를 이용한 부정류 수치모의 결과의 신뢰도를 확신하기가 어렵다. 따라서 본 연구에서는 부정류 수리실험을 수행하여 강변저류지가 있는 하도에서의 HECRAS를 이용한 부정류 수치모의 적용성을 검토하였다. HEC-RAS 적용성 검토는 직선수로에 강변저류지가 설치되어 있거나 그렇지 않은 경우에 대해 부정류 수리실험을 실시하여 측정된 결과와 비교하여 평가하였다. 특히, 강변저류지가 설치되어 있는 경우는 강변저류지의 저류용량이 충분하여 하도에서 강변저류지로 통하는 위어에 완전 횡월류 흐름만 발생하는 경우에 대해 실험을 수행하였다. 강변저류지가 설치되지 않은 직선수로에 대한 HEC-RAS의 수위 계산 결과는 최대 3% 오차를 유량은 최대 1% 오차를 보였으며, 강변저류지가 설치된 경우의 HEC-RAS 수위 계산 결과는 최대 4% 오차를 유량은 최대 2% 오차를 나타냈다. It is necessary to perform the precise analysis of unsteady flow for effective design of the side-weir detention basin installed in the river. Generally, the HEC-RAS program, which is a 1D unsteady numerical model, is mostly used to simulate the unsteady flow for rivers. However, it is difficult to have confidence of unsteady flow results simulated by HEC-RAS due to the lack of experimental data and field monitoring data for the channel with a side-weir detention basin. Therefore, the purpose of this study is to validate or verify the simulation results calculated by HEC-RAS through the experiments for the open channel with a side-weir detention basin using specially-designed unsteady discharge-supply system. The experimental cases included unsteady flows in the straight channel with and without a side-weir detention basin. Especially, for the case with a detention basin, the experiment was performed to consider only the free flow condition over the side-weir. The study results showed that values of water level and discharge obtained from HEC-RAS coincided reasonably with experimental results with the maximum error of 3% for water level and 1% for discharge in the case of the flow without the side-weir detention basin and 4% for water level and 2% for discharge with the side-weir detention basin.

증감부호기를 이용한 순간 대칭비 기반 보행 불균형 평가

김서준,김유현,심현민,윤광섭,이상민,Kim, Seojun,Kim, Yoohyun,Shim, Hyeonmin,Yoon, Kwangsub,Lee, Sangmin 대한의용생체공학회 2014 의공학회지 Vol.35 No.1

In this paper, the gait imbalance evaluation algorithm based on temporal symmetry ratio using encoder is proposed. The device is attached to the hip joint in order to measure the angle during the normal gait. Using an angle data, the stance phase and swing phase was determined. And the value of TSR(temporal symmetry ratio) was calculated by stance phase and swing phase of gait cycle. For the comparative experiment, the conventional method of the foot pressure was measured at the same conditions. The results of statistical analysis, there was a significant difference (p < 0.05) when using encoder. The gait imbalance analysis using encoder is effective in determining the imbalance than using the existing method of pressure.

하천 수위 예측의 불확실성을 고려한 강변저류지 횡월류부 길이 결정 기법

김서준,김상혁,윤병만,Kim, Seojun,Kim, Sanghyuk,Yoon, Byungman 한국수자원학회 2015 한국수자원학회논문집 Vol.48 No.8

하천 주변의 도시화와 이상기후 등으로 인해 기존의 하천 위주의 홍수방어는 한계를 보이고 있으며, 이에 따라 유역통합적인 홍수방어대책의 하나로 강변저류지 설치에 대한 요구가 증대되고 있다. 강변저류지를 치수대책에 포함시키기 위해서는 정량적인 홍수조절효과 산정이 필요하며, 이를 위해서는 강변저류지 홍수조절효과에 영향을 미치는 인자들의 불확실성을 줄이기 위한 노력이 필요하다. 특히 하천 수위 예측의 중요 변수인 하천 조도계수는 항상 불확실성을 포함하고 있으므로, 이를 고려한 설계방법이 필요하다. 따라서 본 연구에서는 상대적으로 설계자가 자유롭게 결정할 수 있는 설계인자인 강변저류지의 횡월류부 길이를 이용하여 하천 조도계수의 불확실성을 고려한 강변저류지 설계 기법을 제안하고자 한다. 이를 위해 HEC-RAS 부정류 수치모형을 이용하여 하천 조도계수와 횡월류부 길이 변화가 홍수조절효과에 미치는 영향을 검토하였고, 분석결과를 이용하여 하천의 수위 예측 불확실성을 고려한 횡월류부 길이를 결정하는 기법을 제시하였다. 본 연구에서 제시한 횡월류부 길이 결정 기법은 하천 수위 예측의 불확실성을 해결할 수 있기 때문에 강변저류지의 홍수조절효과를 좀 더 안전측으로 제시하는데 도움이 될 것으로 기대한다. The existing flood protection in rivers has shown the limitation due to the urbanization around rivers and the abnormal climate. Thus, the demand for the constructions of side-weir detention basin are being increased as a part of integrated watershed flood protection plan. It is necessary to estimate the quantitative flood-control effect for including the side-weir detention basin in flood-control measures. For the determination, it is required to reduce the uncertainty of the design factors which can affect the flood-control effect of side-weir detention basin. Among the factors, however, the water level in river always contains uncertainty. Therefore, the design method considering the uncertainty is required. For the reasons, the design method considering uncertainty of the water level in river is suggested in this study with using the length of side-weir which is relatively easy-determinable by designers. Therefore, it is examined how the variation of the length of side-weir can affect the flood-control effect, using HEC-RAS, and then the method to determine the side-weir length considering the uncertainty of the water level in river through results from analyses. Since the uncertainty of the water level in river can be taken into account in the suggested design method, it is evaluated that the design method is more effective to suggest the flood-control effect of the side-weir type detention basin with higher safety side.

개수로에서의 부정류 수문곡선 재현을 위한 유량공급장치의 개발 및 정확도 분석

김서준,김상혁,윤병만,지운,Kim, Seo-Jun,Kim, Sang-Hyuk,Yoon, Byung-Man,Ji, Un 한국수자원학회 2012 한국수자원학회논문집 Vol.45 No.8

시간에 따른 하도의 수위 및 유량 변화에 영향을 많이 받는 수리구조물의 설계에 있어서 부정류 흐름 해석은 반드시 필요하다. 일반적으로 부정류 흐름 해석에는 수치모형이 많이 활용되고 있으나 수치모형의 검 보정을 위한 현장 자료의 획득이 어려운 경우가 많다. 또한 자료구축이 가능하더라도 인력과 비용이 많이 소모되며, 측정 정확도를 신뢰하기 어려운 경우가 많다. 이러한 경우 수치모형의 검 보정을 위해 부정류 수리실험을 통해 획득되는 자료를 활용하는 것이 대안이 될 수 있다. 따라서 본 연구에서는 다양한 형태의 부정류 수문곡선을 실험에서 재현할 수 있는 유량공급장치를 개발하고자하며, 개발된 부정류 유량공급장치를 이용하여 수리실험 수로에서 재현되는 수문곡선과 목표 수문곡선을 비교 분석함으로써 재현 정확도를 정량적으로 평가하고자 한다. 본 연구에서는 유량이 급격하게 증가 또는 감소하는 사각형 형태, 첨두유량 발생 시간이 짧은 삼각형 형태 및 일반적인 홍수 수문곡선 형태의 종(bell) 형태 수문곡선을 대상으로 재현 오차 및 Root Mean Square Error (RMSE)를 분석하였다. 재현 정확도 분석 결과, 사각형 형태의 수문곡선 재현 오차는 약 59% 정도로 가장 크게 나타났으며, 삼각형 형태의 수문곡선은 단일첨두와 이중첨두 형태 모두 약 10% 정도의 재현 오차가 나타났지만 홍수 수문곡선 형태인 종 모양의 수문곡선의 재현 오차는 최대 2% 이내인 것으로 나타났다. The analysis for unsteady flow is necessary to design the hydraulic structures affected by water level and discharge changes through time. The numerical model has been generally used for unsteady flow analysis, however it is difficult to acquire field data to calibrate and validate the numerical model. Even though it is possible to collect field data for some case, high cost and labor are required and sometimes it is considered that the confidence of measured data is very low. In this case, the experimental data for unsteady flow can be used to calibrate and validate the numerical model as an alternative. Therefore, the discharge-supply system which could generate various type of unsteady flow hydrograph was developed in this study. Also, the accuracy of the unsteady flow hydrograph generated by developed dischargesupply system in the experiment was evaluated by comparing with target hydrograph. Accuracy errors and Root Mean Square Error (RMSE) were analyzed for the rectangular-type hydrograph with sudden changes of flow, triangular-type hydrograph with short peak time, and bell-type flood hydrograph. As a result, the generating error of the discharge-supply system for the rectangular-type hydrograph was about 59% which was maximum error among various types. Also, it was represented that RMSE for the triangular-type hydrographs with single and double peaks were approximately corresponding to 10%. However, RMSE for the bell-type flood hydrograph was lower than 2%.

표면영상유속계(SIV)를 이용한 현장유량측정

김서준,주용우,류권규,윤병만,Kim. Seo-Joon,Joo. Yong-Woo,Yu. Kwon-Kyu,Yoon. Byung-Man 한국방재학회 2008 한국방재학회 학술발표대회논문집 Vol.2008 No.1

표면영상유속계(SIV)는 기존의 입자영상유속계(PIV)의 원리를 이용하여 하천의 표면유속을 측정하는 방법이다. 본 연구에서는 경제적이고 효율적인 유속측정 기법인 SIV 기법을 이용하여 국내 3개 하천에 대하여 현장 유량측정에 적용하였다. 현장 영상분석은 다중카메라 방식을 이용하였고 영상분석과정에 필요한 참조점과 횡단면 자료는 측량을 통하여 획득하였다. SIV로 측정된 유속을 검증하는 수로 실험의 결과, 평균오차 10% 이내의 정확도를 보여 정확한 유속측정이 가능함을 확인하였다. 그러나, 실제 하천에의 적용에서는 저수위시와 악천후시에 대해서는 20 % 이내의 오차를 보이는 것으로 나타났다. 향후 SIV 기법의 문제점들을 해결한다면 언제 어디서나 효율적이고 경제적인 유량측정을 할 수 있을 것이다. 그리고 이를 활용하여 실시간 하천정보시스템으로 발전시킴으로써 하천 관리에 큰 도움이 될 것이라 판단된다. Surface Image Velocity (SIV) is a technique which measures the surface velocity of river by using the principle of Paticle Image Velocimetry (PIV). The technique is economical and efficient way to measure velocity in rivers. The present paper aims to apply the technique to three rivers in Korea. It uses pairs of river surface images taken with two digital-cameras and reference points and cross section data which were acquired through plane survey. The performance of SIV was verified with automatic cart on an experimental flume. The test revealed that average error was less than 10 %, which assures that SIV can be used to measure velocity accurately. When it was applied to rivers with low water levels or rough weather condition, however, it showed the error about 20 %. If the problems of SIV technique are settled down, it can be one of the most convenient and economical ways to measure water discharge anytime and anywhere. And then it would be helpful to river management as developing a real-time river information system.

2차원 특징점 추출 기법 기반 근전도 신호 패턴 분류 알고리즘

김서준(S. J. Kim),정의철(E. C. Jung),유송현(S. H. Yu),송영록(Y. R. Song),이상민(S. M. Lee) 한국재활복지공학회 2012 한국재활복지공학회 학술대회논문집 Vol.2012 No.4

횡월류위어의 잠긴 흐름을 고려한 강변저류지의 홍수조절효과 분석

김서준(Kim, Seojun),김상혁(Kim, Sanghyuk),박갑렬(Park, Kabyul),윤병만(Yoon, Byungman) 대한토목학회 2013 대한토목학회 학술대회 Vol.2013 No.10

바울서신의 ‘속죄’와 ‘화해’ 용어에 대한 비판적 고찰 - ίλαστήριον과 καταλλαγή의 해석의 문제를 중심으로 -

김서준(Seo-Jun Kim) 대한성서공회 2020 성경원문연구 Vol.0 No.47

The present article examines the terms ‘sokjoe’ and ‘hwahae’ (‘hwamok’) used in Korean Bible translations, particularly in Paul’s epistles. It first investigates the meanings of the Greek expressions behind ‘sokjoe’ and ‘hwahae’ (‘hwamok’), namely ἱλαστήριον, καταλλαγή, and καταλλάσσω, in light of their usage in various ancient writings available in Paul’s time. Then based on the results of this investigation, it examines the theological meanings of those terms in Paul’s epistles to reconsider the validity of their Korean translations. With regard to the Korean translations of ἱλαστήριον in Rom 3:25, neither the New Korean Revised Version (NKRV) nor the Revised New Korean Standard Version (RNKSV) provides precise translation. A survey of the use of ἱλαστήριον in the Septuagint reveals that its central meaning is to cover, close, or wrap. It can also mean block or countervail. In the Septuagint, it refers to various objects that cover or wrap (Exo 25:17-22; 31:7; 35:12; 38:5,7 ff; Lev 16:2,13-15; Num 7:89; Eze 43:14,17,20; [Symmachus] Gen 6:16; Amo 9:1). In the context of Hellenistic religions, it refers to an object that functions to block divine wrath (Cos Nr. 80; Cos Nr. 347; Bullettino del Museo dell"Impero Romano Nr. 11) ; SEG LIV 796; Lindos 2. Inschriften, Nr. 425; Tempelchronik von Lindos B 49, Z. 48-50; Dio Chrysostomus, Or 11,121; Josephus, Ant, 16.182). In Rom 3:25 and 4 Maccabees 17:21-22, the same word is used in relation to the blood and the death of a person, which function to cover the sins of sinners and block God’s wrath. When Paul in Rom 3:25 mentions Jesus’ blood while presenting Jesus as ἱλαστήριον put forward by God, this word conveys the meaning of Christ’s death, namely that the blood shed by Christ is able to cover human sins or block/countervail divine wrath. A survey of the καταλλα-word group shows that it is clearly distinguished from the ἱλασ-word group, and that it basically signifies the restoration of peace by ending hostility, namely reconciliation (‘hwahae’) rather than simply warm relationship among members (‘hwamok’). Paul uses καταλλαγή and καταλλάσσω to refer to the event of reconciliation between God and man through Christ Jesus. Just as δικαιοσύνη, frequently used by Paul, describes one aspect of salvation, καταλλαγή and καταλλάσσω also describe another aspect of salvation that God achieved through his Son, Jesus, namely that God resolved hostility between God and humanity through his Son, and that there is therefore no need to fear God’s wrathful judgment on sin and injustice. In summary, ἱλαστήριον, καταλλαγή, and καταλλάσσω in the Pauline epistles describe different aspects of the meaning of Jesus Christ"s death on the cross. While ἱλαστήριον directly communicates the role and the meaning of Christ’s death, καταλλαγή and καταλλάσσω refer to an event that results from his death. In view of this clear semantic distinction between ἱλαστήριον and καταλλαγή /καταλλάσσω, we are thus not justified to conflate the meanings of these two words, and use both ‘sokjoe’ and ‘hwamok’ for the translation of ἱλαστήριον. Furthermore, we need to remember the particular meanings of Christ’s death expressed by Paul’s specific choice of the words, ἱλαστήριον, καταλλαγή, and καταλλάσσω. It is by understanding these meanings clearly that we can come closer to the original representation of salvation that Paul communicated two thousand years ago.

회전 흐름의 유속 측정을 위한 표면영상유속계의 적용성 검토

김서준(Kim, Seojun),류권규(Yu, Kwonkyu),윤병만(Yoon, Byungman),김상혁(Kim, Sanghyuk) 대한토목학회 2013 대한토목학회 학술대회 Vol.2013 No.10

Ethnic Cleansing as a Distinct Crime under International Law: Assessing the Case of Forcible Transfer of Ethnic Koreans in the Former USSR(1937)

김서준(Alexander Kim) 국제법평론회 2022 국제법평론 Vol.- No.63

The forcible transfer of ethnic Koreans in 1937 marked the first precedent of the policy of wholesale eviction and displacement of populations as an instrument of ethnic cleansing in the USSR and became a pattern during and after World War II, when different ethnic minorities amounting to around 6 million people have been uprooted from their homes, with 1 to 1.5 million estimated to have perished as a result of forced internal displacement. The present research considers the forced internal displacement of the ethnic Korean population in the USSR to be an act of ethnic cleansing, which is a mass atrocity crime and a blatant human rights violation. Inability to bring the perpetrators to justice for forced displacement of the entire civilian population of ethnic Koreans in the USSR, which has caused the physical extermination of several thousand people and the destruction of their socio-economic infrastructures and culture, will remain in history as the most serious form of impunity and the most flagrant violation of the fundamental right of victims to justice. The state cannot be held accountable for this wrongful act since the Soviet Union, as a subject of international and geopolitical reality, no longer exists and ethnic cleansing has not yet been recognized as an independent crime under international law. International law sets out the human rights and each State and other authorities have a prime responsibility and duty to protect, promote and implement all these rights and fundamental freedoms, and it is essential to carry out protection activities at the national and international level. While the prohibition of forced displacement itself has been a well-established feature of international criminal law since the Nuremberg trials following the Second World War, ethnic cleansing has not yet been written and signed in any UN treaty, which means Member States do not have to protect those who have fallen victim, since ethnic cleansing is still not a criminal charge in international law. But in 2005, a UN World Summit included ethnic cleansing along with genocide, war crimes, and crimes against humanity as four things from which each individual State has a duty to protect their populations. Despite the fact that forcible transfer and other practices involving the coerced, arbitrary or involuntary displacement of the civilian population from their homes, lands, and communities constitute a specific phenomenon, there is no single legal principle in international law that can be applied to all kinds of population transfers. In some circumstances, deportation or internal displacement as well as other forms of involuntary population transfers may amount to a crime against humanity, a crime of genocide or a war crime, depending on the factual elements of the case and the specific requirements of a certain crime. This study accordingly reviews population transfers as the constitutive element of such crimes as genocide and crimes against humanity, and transposes this comparative analysis into the context of ethnic cleansing. Every state has the responsibility to protect its population from four mass atrocity crimes: genocide, war crimes, crimes against humanity (that have not yet been codified in a separate treaty of international law), and ethnic cleansing (that has not been recognized as an independent crime under international law). The term ‘ethnic cleansing’ itself has been acknowledged in judgments and indictments of the International Criminal Tribunal for the Former Yugoslavia, although it did not constitute one of the counts for prosecution. One aspect of the criticism of the terms ‘ethnic cleansing’ focuses primarily on the fact that many state governments use this term even when an incident can be classified as genocide in order not to use state resources or taking action against the perpetrating State.