This study aims to create a disaster management system after an earthquake. Japan’s earthquake disaster management system, including the Disaster Countermeasures Basic Act, addresses all of the disaster phases of prevention, mitigation, preparedness and emergency response as well as recovery and reconstruction with roles and responsibilities among the national and local governments clearly defined. Korea’s earthquake disaster management system are including the Disaster Countermeasures Basic, but when the 9.12 earthquake occurred, problems such as insufficient early response, study on the earthquake lack were revealed. This study conducted a field survey and analyzed coping process after Po Hang earthquake. Therefore, this study have found that Disaster Management Headquarters are operated rapidly. They are coped with urgent safety inspection for damage facilities and soil liquefaction with advanced equipment. And The headquarters interviewed with victims. So they found out What the victims needed. However, when carrying out relief activities, Research of temporary housing and allocation of donations was not rapid. Further, this study have found that earthquake specialists were lack and disaster information transfer was not working. This study will be utilized as fundamental data in planning disaster management system after an earthquake.

In this paper, comparative analysis of the 9.12 Gyeongju and 11.15 Pohang earthquakes was conducted in order to provide probable explanations and reasons for the damage observed in the 11.15 Pohang earthquake from both earthquake and structural engineering perspectives. The damage potentials like Arias intensity, effective peak ground acceleration, etc observed in the 11.15 Pohang earthquake were generally weaker than those of the 9.12 Gyeongju earthquake. However, in contrast to the high-frequency dominant nature of the 9.12 Gyeongju earthquake records, the spectral power of PHA2 record observed in the soft soil site was highly concentrated around 2Hz. The base shear around 2 Hz frequency was as high as 40% building weight. This frequency band is very close to the fundamental frequency of the piloti-type buildings severely damaged in the northern part of Pohang. Unfortunately, in addition to inherent vertical irregularity, most of the damaged piloti-type buildings had plan irregularity as well and were non-seismic. All these contributed to the fatal damage. Inelastic dynamic analysis indicated that PHA2 record demands system ductility capacity of 3.5 for a structure with a fundamental period of 0.5 sec and yield base shear strength of 10% building weight. The system ductility level of 3.5 seems very difficult to be achievable in non-seismic brittle piloti-type buildings. The soil profile of the PHA2 site was inversely estimated based on deconvolution technique and trial-error procedure with utilizing available records measured at several rock sites during the 11.15 Pohang earthquake. The soil profile estimated was very typical of soil class D, implying significant soil amplification in the 11.15 Pohang earthquake. The 11.15 Pohang earthquake gave us the expensive lesson that near-collapse damage to irregular and brittle buildings is highly possible when soil is soft and epicenter is close, although the earthquake magnitude is just minor to moderate (M 5+).

A total of 594 reservoirs (17%), which are managed by KRC, equipped with earthquake-resistant facilities whereas remaining ones did not. In addition, reservoirs were placed without the effect of geological structures (i.e., fault and lineament). Therefore, development on technique for alleviating the potential hazards by natural disasters along faults and lineaments has required. In addition, an effective reinforcement guideline related to the geological vulnerabilities around reservoirs has required. The final goal of this study is to suggest the effective maintenance for the safety of earth fill dams. A radius 2 km, based on the center of the reservoir in the study area was set as the range of vulnerability impacts of each reservoir. Seismic design, precise safety diagnosis, seismic influence and geological structure were analyzed for the influence range of each reservoir. To classify the vulnerability of geological disasters according to the fault distribution around the reservoir, evaluation index of seismic performance, precise safety diagnosis, seismic influence and geological structure were also developed for each reservoir, which were a component of the vulnerability assessment of geological disasters. As a result, the reservoir with the highest vulnerability to geological disasters in the pilot district was analyzed as Kidong reservoir with an evaluation index of 0.364. Within the radius of 100km from the epicenter of the Pohang earthquake, the number of agricultural infrastructure facilities subject to urgent inspections were 1,180 including reservoirs, pumping stations and intakes. Four reservoirs were directly damaged by earthquake among 724 agricultural reservoirs. As a result of the precise inspection and electrical resistivity survey of the reservoir after the earthquake, it was reported that cracks on the crest of reservoirs were not a cause of concern. However, we are constantly monitoring the safety of agricultural facilities by Pohang aftershocks.

Pohang earthquake occurred on November 15, 2017, with a magnitude of 5.4. The damage of the structure caused by the Pohang earthquake was the most significant in 4-story piloti-type buildings, where the damage patterns were different according to the location of columns and walls at the first story. One　building with a staircase at a corner shows shear failure at columns, and Another building with a staircase in the middle shows no failure or shear failure at staircase walls. Therefore, two different piloti-type buildings were selected; one has a staircase at a corner and another has in the middle, and the seismic behavior of the buildings were examined by nonlinear dynamic analysis applying a ground motion measured at Pohang. Analytical model well simulated the actual behavior of the piloti-type buildings during the earthquake. Analysis results showed that walls have an insufficient shear strength wherever the location of the staircase is and columns with insufficient transverse reinforcement could be failed when the staircase is located at a corner. Conclusively, structural engineers should design columns and walls in piloti-type buildings to possess sufficient capacity according to the location of staircase.

On November 15, 2017, Pohang earthquake occurred. Its local magnitude was announced to be ML=5.4 by Korea Meteorological Administration (KMA). Ground motion data recorded at KMA stations were obtained from their data bases. From the data, horizontal and vertical response spectra, and V/H ratio were calculated. The horizontal spectra were defined as GMRotI50 spectra. From the statistical analysis of the GMRotI50 spectra, a mean plus one standard deviation spectrum in lognormal distribution is obtained. Regression analysis is performed on this curve to determine the shape of spectrum including transition periods. Applying the same procedure, the shape and transition periods of vertical spectrum were obtained. These results were compared with the Korean standard design spectra, which were developed from domestic and overseas intra-plate earthquake records, and Gyeongju earthquake response spectra. The response spectra of Pohang earthquake were found to be almost identical with the newly proposed design spectra. Even the V/H ratios showed good agreement. These results confirmed that the method adopted when developing the standard design spectra were valid and the developed design spectra were reliable.

Severe earthquakes can cause damage to society both socially and economically. An appropriate initial response can alleviate damage from severe earthquakes. In order to formulate an appropriate initial response, it is necessary to identify damage situations in societies; however, it is difficult to grasp this information immediately after an earthquake event. In this study, an earthquake damage assessment methodology for buildings is proposed for estimating damage situations immediately after severe earthquakes. A response spectrum database is constructed to provide response spectra at arbitrary locations from earthquake measurements immediately after the event. The fragility curves are used to estimate the damage of the buildings. Earthquake damage assessment is performed from the response spectrum database at the building scale to provide enhanced damage condition information. Earthquake damage assessment for Gyeongju city and Pohang city were conducted using the proposed methodology, when an earthquake occurred on September 12, 2016, and November 15, 2017. Results confirm that the proposed earthquake damage assessment effectively represented the earthquake damage situation in the city to decide on an appropriate initial response by providing detailed information at the building scale.

The probabilistic seismic safety assessment is one of the methodology to evaluate the seismic safety of the nuclear power plants. The site characteristics of the nuclear power plant should be reflected when evaluating the seismic safety of the nuclear power plant. The Korea seismic characteristics are strong in high frequency region and may be different from NRC Regulatory Guide 1.60, which is the design spectrum of nuclear power plants. In this study, seismic response of a nuclear power plant structure by Pohang earthquake (2017.11.15. (KST)) is investigated. The Pohang earthquake measured at the Cheongsong seismic observation station (CHS) is scaled to the peak ground acceleration (PGA) of 0.2 g and the seismic acceleration time history curve corresponding to the design spectrum is created. A nuclear power plant of the containment building and the auxiliary buildings are modeled using OPENSEES to analyze the seismic response of the Pohang earthquake. The seismic behavior of the nuclear power plant due to the Pohang earthquake is investigated. And the seismic performances of the equipment of a nuclear power plant are evaluated by the HCLPF. As a result, the seismic safety evaluation of nuclear power plants should be evaluated based on site-specific characteristics of nuclear power plants.

This study examines the seismic failure of RC low-rise building structures having irregularities at the ground story during the 15 November 2017 Pohang, Korea, earthquake, Mw = 5.4, which is the second strongest since the government began monitoring them in 1978 in South Korea. Some 2,000 private houses were damaged or destroyed in this earthquake. Particularly, serious damage to the piloti story of RC low-rise residential building structures of fewer than five stories was observed within 3 km of the epicenter with brittle shear failure of columns and walls due to severe torsional behavior. Buildings below six stories constructed before 2005 did not have to comply with seismic design requirements, so confinement detailing of columns and walls also led to inadequate performance. However, some buildings constructed after 2005 were damaged at the flexible side of the piloti story due to the high torsional irregularity. Based on these results, this study focuses on the problems of the seismic torsion design approach in current building codes.

A nepticulid leaf-mine ichnofossil is described on the basis of a fossil leaf of Fagus from the early Miocene Geumgwangdong Formation (ca. 21–14 million years ago) in Pohang basin. This mine trace is characterized by a linear-blotch type with clear centric frass trail of closely and randomly dispersed pellets filling the mine width in early stage. We found traces of possible egg case and exit slit from the fossil. These features are most consistent with those produced by Nepticulidae. Our record represents the only reliably-identified nepticulid leaf-mine on Fagus in Miocene. Nepticulid leaf-mines in Miocene and the leaf-mine fossils from the Geumgwangdong Formation are briefly reviewed.

내연산일대 산림식생의 생태적 관리를 위한 기초자료 제공을 목적으로 Z.-M.학파의 식물사회학적 방법으로 총 149개의 표본조사구에서 식생조사를 실시하여 식생유형을 구분하고 그 생태적 특성을 파악하였다. 산림식생은 종조성 측면에서 총 10개 유형으로 구분되었고 2개 군락군, 4개 군락, 6개 아군락 그리고 6개 변군락의 단위체계를 가지고 있었다. 상층 우점종에 의한 상관식생은 총 19개 유형으로 구분되었고 이 중 자연식생은 신갈나무군락, 소나무군락, 망개나무군락, 헛개나무군락 등 18개 유형 그리고 인공식생은 일본잎갈나무림 1개 유형이었다. 구성종의 중요치 분석 결과 잠재자연식생 요소인 신갈나무가 다른 구성종에 비하여 대부분의 임분에서 상대적으로 중요치가 높게 나타나 인위적 간섭이 없는 한 일부 입지를 제외하고 대부분 신갈나무군락으로의 변화가 예상되었다. 산림식생의 공간분포 특성을 파악하기 위하여 상층 우점종에 의해 1/5,000 대축척 현존상관식생도를 작성한 결과, 자연식생이 98.2%로 대부분을 차지하고 있었으며, 식생 패치수는 733개 그리고 패치당 평균면적은 3.93ha로 나타났다.

포항시 마이오세 두호층에서 2개의 신생대 어류 화석들이 발견되었다. 두호층에서 발견된 이 어류 화석들은 다 음과 같은 근거로 도다리속으로 동정되었다. 첫째, 앞쪽 등지느러미가 두개부 위까지 연장되어 뻗어있다. 둘째, 두개골 에서 안와는 모두 오른쪽에 몰려있는 비대칭성을 갖는다. 셋째, 낚시 바늘 모양의 미설골을 지닌다. 넷째, 미설골의 좌 골부가 꺾여있다. 다섯째, 후의쇄골이 존재한다. 여섯째, 척추체의 개수가 27개를 넘는다. 일곱째, 첫 번째 뒷지느러미 담기골이 연장되어 있다. 여덟째, 미설골의 내연부가 ‘c’자 형태를 갖는다. 아홉째, 분문돌기가 작거나 거의 없다. 열째, 몸에 여러 반점들이 존재한다. 도다리속 어류 화석은 동아시아에서 최초로 보고되는 것이다. 두 표본은 두개골의 비대 칭성과 납작한 정도에서 해부학적 차이가 존재한다. 이는 가자미과 어류의 독특한 개체발생 단계를 나타내는 데, 그들 은 표영성 생활 양식에서 저서성 생활 양식으로 전환할 때 위와 같은 해부학적 차이를 수반하기 때문이다.

정부는 해양환경복원과 수산자원을 회복하기 위해 1971년부터 2014년까지 약 44년 동안 222,627ha의 인공어초어장 을 조성하였다. 그러나 인공어초 설치사업은 증가되고 있는 반면 아직까지 설치된 어초의 효과에 대한 연구는 부족한 실정이다. 이에 본 연구에서는 포항시 장길리 해역에 설치된 뿔삼각형어초에 부착·서식하는 저서동물의 시간적 군집변 화를 살펴보기 위해 2003년 포항시 장길리 해역 수심 5∼7m에 설치된 뿔삼각형어초를 대상으로 2009년 2월부터 2011년 8월까지 총 4회에 걸쳐 어초에 부착된 저서동물의 군집을 분석하였다. 그 결과 우점하는 분류군은 연체동물이고 우점종은 바다방석고둥인 것으로 나타났다. 또한 출현종들은 대부분 시공간의 변화에 따라 달라지는 양상을 보였다. 따라서 이 연구를 통해 시설해역과 목적하는 종의 특성에 적합한 인공어초 개발 연구, 사후관리에 관한 이용, 관리제도 제정 등에 활용될 것으로 기대한다.

신생대 어류 화석 4개체가 포항의 마이오세 두호층에서 발견되었다. 본 화석은 뒷지느러미의 앞쪽 담기골 (pterygiophore)이 연장되어 있고, 후의쇄골(postcleithrum)이 존재하며, 두 개의 인접한 혈관극 사이에 뒷지느러미 담기 골 두개가 거의 일정하게 존재한다. 그리고 첫 번째와 두 번째 하미축골(hypurals)이 융합되었고, 세 번째와 네 번째 하 미축골과 첫 번째 전미추체(preural centrum)가 융합되어 있다. 그리고 두부인근의 잘 발달된 판상 신경극과 낚시바늘 모양의 미설골(urohyal)이 존재하고, 그 좌골부(sciatic part)가 꺾여있다. 그리고 준하미골(parahypural)이 첫 번째 전미추 체로부터 분리되어 있다. 이를 근거로 볼 때, 이 화석은 국내 최초의 가지미목으로 동정되었다. 그간의 두호층 지질학 적 연구는 천해환경의 생물들이 육상의 큰 홍수와 같은 사건으로 떠내려가 저탁류에 의해 심해환경에서 퇴적되었다고주장해 왔다. 하지만 여태껏 천해환경 생물들만 발견되어 왔다. 본 연구에서는 두호층에서 최초로 심해생물인 가자미류 가 보고되었다.

Species composition and bycatch rate of the catches by dredge with bycatch reduction device to reduce bycatch were estimated around Yeongil Bay, Korea at June, 2015. Total catches were collected 31 species as Chordata 10 species, mollusca 8 species, arthropoda 6 species, echinodermata 5 species, sipunculida 1 species, annelida 1 species during the experiment at the Yeongil Bay. The dominant species were Scapharca broughtonii, Callithaca adamsi, and Atrina pectinata and they reached 79.9% of the total catch. The catch rate of Scapharca broughtonii and Callithaca adamsi was 69.6% and 10.4% respectively. The rate of bycatch was 20.1%, consisted with Echinodemata 13.0%, Chordata 3.6%. The catch of ordinary dredge was 27 species 1,307 number 85,052g and that of dredge with escapement device was 21 species 1,690 number 91,648g. In conclusion, the dredge gear with bycatch reduction device has higher catch rate of target species and lower bycatch rate to non–target species than ordinary one.

포항시 하수처리수 재이용 시설은 UF-RO 공정을 통해서 일 10만 톤의 재이용수를 생산하여 철강 산업단지에 공급하는 시설로서 2014년 8월부터 운영 중이며, 2020년 기준 포항시에서 예상되는 물 부족량의 45%를 충당할 것으로 예상한다. 본 시설의 전처리 공정은 침지형 UF 막으로, 회수율 95%, Flux 25.7 L/m²-h로 운영되며, 역삼투 분리막은 회수율 80%, Flux 20 L/m²-h로 운영된다. 농축수 25,000톤 중 9,000톤은 생물 막 여과를 통해 처리되어 방류되며, 16,000톤은 하수처리장으로 반송된다. 본 연구에서는 하수처리수 재이용 시설의 분리막 오염 특성에 대해서 살펴보고 운전 자료를 바탕으로 안정적인 실시간 운영을 위한 공정 구성 및 운전 방법에 대해 검토하였다.

경상북도 포항시 북부해수욕장 부근 일대에 분포하는 마이오세의 두호층에서 산출된 3개의 꼬투리 화석을 Albizia miokalkora Hu and Chaney로 동정하였다. 이 화석은 현재까지 한국, 중국, 일본의 제 3기 마이오세 식물군에서 유일하게 산출되고 있고, 난온대에서 아열대-열대 지역에 걸쳐 광범위하게 나타나지만 종의 다양성은 매우 낮았다고 생각된다. 화석 Albizia miokalkora Hu and Chaney는 난온대와 아열대-열대 기후와 같은 따뜻한 기후에 적응한 식물로 추정된다.

Three species of Pseudolarix including P. japonica, P. sp. A, and P. sp. B, all belonging to Pinaceae, are systematically described from the Middle Miocene Duho Formation of the Yeonil Group based on the detached seminiferous scales. The presence of Pseudolarix in the Yeonil flora indicates that various kinds of Pinaceae did flourish during the Middle Miocene. The occurrence of Pseudolarix is the first record in the Korean Tertiary flora.

경상북도 포항시 북부해수욕장 부근과 창포동 일대에 분포하는 마이오세의 두호층에서 Albizia miokalkora의 열매화석 두개가 채집되었다. 꼬투리는 편평하고 길며 7개의 종자가 들어있다. 꼬투리 화석은 비록 인상이기는 하지만 완전한 형태를 보여준다. 화석 Albizia는 동아시아에서 온난한 온대기후에서 번성한 식물로 판단된다. 이 화석의 산출은 우리나라 신제3기의 식물군에서 두 번째 기록이다.