New piezoelectric and triboelectric materials for energy harvesting are being widely researched to reduce their processing cost and complexity and to improve their energy conversion efficiency. In this study, BaTiO3 films of various thickness were deposited on Ni foams by R.F. magnetron sputtering to study the piezoelectric and triboelectric properties of the porous spongy structure materials. Then piezoelectric nanogenerators (PENGs) were prepared with spongy structured BaTiO3 and PDMS composite. The output performance exhibited a positive dependence on the thickness of the BaTiO3 film, pushing load, and poling. The PENG output voltage and current were 4.4 V and 0.453 μA at an applied stress of 120 N when poled with a 300 kV/cm electric field. The electrical properties of the fabricated PENG were stable even after 5,000 cycles of durability testing. The triboelectric nanogenerators (TENGs) were fabricated using spongy structured BaTiO3 and various polymer films as dielectrics and operated in a vertical contact separation mode. The maximum peak to peak voltage and current of the composite film-based triboelectric nanogenerator were 63.2 V and 6 μA, respectively. This study offers new insights into the design and fabrication of high output nanogenerators using spongy structured materials.

BaTiO3-Poly vinylidene fluoride (PVDF) solution was prepared by adding 0~25 wt% BaTiO3 nanopowder and 10 wt% PVDF powder in solvent. BaTiO3-PVDF film was fabricated by spreading the solution on a glass with a doctor blade. The output performance increased with increasing BaTiO3 concentration. When the BaTiO3 concentration was 20 wt%, the output voltage and current were 4.98 V and 1.03 μA at an applied force of 100 N. However, they decreased when the over 20 wt% BaTiO3 powder was added, due to the aggregation of particles. To enhance the output performance, the generator was poled with an electric field of 150~250 kV/cm at 100 °C for 12 h. The output performance increased with increasing electric field. The output voltage and current were 7.87 V and 2.5 μA when poled with a 200 kV/cm electric field. This result seems likely to be caused by the c-axis alignment of the BaTiO3 after poling treatment. XRD patterns of the poled BaTiO3-PVDF films showed that the intensity of the (002) peak increased under high electric field. However, when the generator was poled with 250 kV/cm, the output performance of the generator degraded due to breakdown of the BaTiO3-PVDF film. When the generator was matched with 800 Ω resistance, the power density of the generator reached 1.74 mW/m2. The generator was able to charge a 10 μF capacitor up to 1.11 V and turn on 10 red LEDs.

K0.5Bi0.5TiO3 (KBT) thin films were prepared by sol-gel processing for future use in piezoelectric generators. It is believed that the annealing temperature of films plays an important role in the output performance of piezoelectric generators. KBT films prepared on Ni substrates were annealed at 500 ~ 700 oC. Tetragonal KBT films were formed after annealing process. As the annealing temperature increased, the grain size of KBT films increased. KBT thin films show piezoelectric constant (d33) from 23 to 41 pC/N. The increase of grain size in KBT films brought about output voltage and current in the KBT generators. Also, the increase in the displacement of specimens during bending test resulted in increases in output voltage and current. Although KBT generators showed lower output power than those of generators prepared using NBT films, as reported previously, the KBT films prepared by sol-gel method show applicability as piezoelectric thin films for lead-free nanogenerators, along with NBT films.

Acoustic surveys using a scientific echosounder and trawl surveys were concurrently carried out in between Geoje and Tongyeong of the South Sea by season. The anchovy schools were identified by trawling in each station and used for frequency response analysis. Frequency responses of anchovy schools by season and species composition ratio were examined using multi-frequencies (18, 38, 70, 120 and 200 kHz). The frequency response r(f), is one of the acoustic characteristics which means the volume back-scattering strength ratio between a reference frequency and other frequencies. In spring, the r(f) of anchovy schools decreased with increased frequency, with the exception of 120kHz. While, in winter, the r(f) continuously decreased inversely proportional to the increase in frequency. Frequency response of anchovy schools presented a distinctive difference between spring and winter, however it did not different in spife of different species composition ratios in schools.

ZrO2 films were coated on aluminum etching foil by the sol-gel method to apply ZrO2 as a dielectric material in an aluminum(Al) electrolytic capacitor. ZrO2 films annealed above 450˚C appeared to have a tetragonal structure. The withdrawal speed during dip-coating, and the annealing temperature, influenced crack-growth in the films. The ZrO2 films annealed at 500˚C exhibited a dielectric constant of 33 at 1 kHz. Also, uniform ZrO2 tunnels formed in Al etch-pits 1μm in diameter. However, ZrO2 film of 100-200 nm thickness showed the withstanding voltage of 15 V, which was unsuitable for a high-voltage capacitor. In order to improve the withstanding voltage, ZrO2-coated Al etching foils were anodized at 300 V. After being anodized, the Al2O3 film grew in the directions of both the Al-metal matrix and the ZrO2 film, and the ZrO2-coated Al foil showed a withstanding voltage of 300 V. However, the capacitance of the ZrO2-coated Al foil exhibited only a small increase because the thickness of the Al2O3 film was 4-5 times thicker than that of ZrO2 film.

TiO2 thin films for high energy density capacitors were prepared by r.f. magnetron sputtering at room temperature.Flexible PET (Polyethylene terephtalate) substrate was used to maintain the structure of the commercial film capacitors. Theeffects of deposition pressure on the crystallization and electrical properties of TiO2 films were investigated. The crystal structureof TiO2 films deposited on PET substrate at room temperature was unrelated to deposition pressure and showed an amorphousstructure unlike that of films on Si substrate. The grain size and surface roughness of films decreased with increasing depositionpressure due to the difference of mean free path. X-ray photoelectron spectroscopy (XPS) analysis revealed the formation ofchemically stable TiO2 films. The dielectric constant of TiO2 films was significantly changed with deposition pressure. TiO2films deposited at low pressure showed high dissipation factor due to the surface microstructure. The dielectric constant anddissipation factor of films deposited at 70mTorr were found to be 100~120 and 0.83 at 1kHz, respectively. The temperaturedependence of the capacitance of TiO2 films showed the properties of class I ceramic capacitors. TiO2 films deposited at10~30mTorr showed dielectric breakdown at applied voltage of 7V. However, the films of 500~300nm thickness depositedat 50 and 70mTorr showed a leakage current of ~10−8~10−9 A at 100 V.

In this study, optical emission spectroscopy was used to monitor the plasma produced during the RF magnetron sputtering of a BaTiO3 target. The intensities of chemical species were measured by real time monitoring with various discharge parameters such as RF power, pressure, and discharge gas. The emission lines of elemental and ionized species from BaTiO3 and Ti targets were analyzed to evaluate the film composition and the optimized growth conditions for BaTiO3 films. The emissions from Ar(I, II), Ba(I, II) and Ti(I) were found during sputtering of the BaTiO3 target in Ar atmosphere. With increasing RF power, all the line intensities increased because the electron density increased with increasing RF power. When the Ar pressure increased, the Ba(II) and Ti(I) line intensity increased, but the Ar+ line intensity decreased with increasing pressure. This result shows that high pressure is of greater benefit for the ionization of Ba than for that of Ar. Oxygen depressed the intensity of the plasma more than Ar did. When the Ar/O2 ratio decreased, the intensity of Ba decreased more sharply than that of Ti. This result indicates that the plasma composition strongly depends on the discharge gas atmosphere. When the oxygen increased, the Ba/Ti ratio and the thickness of the films decreased. The emission spectra showed consistent variation with applied power to the Ti target during co-sputtering of the BaTiO3 and Ti targets. The co-sputtered films showed a Ba/Ti ratio of 1.05 to 0.73 with applied power to the Ti target. The films with different Ba/Ti ratios showed changes in grain size. Ti excess films annealed at 600˚C did not show the second phase such as BaTi2O5 and TiO2.

Mn-substituted BiFeO3(BFO) thin films were prepared by r.f. magnetron sputtering under an Ar/O2mixture of various deposition pressures at room temperature. The effects of the deposition pressure andannealing temperature on the crystallization and electrical properties of BFO films were investigated. X-raydiffraction patterns revealed that BFO films were crystallized for films annealed above 500oC. BFO filmsannealed at 550oC for 5 min in N2 atmosphere exhibited the crystallized perovskite phase. The (Fe+Mn)/Biratio decreased with an increase in the deposition pressure due to the difference of sputtering yield. The grainsize and surface roughness of films increased with an increase in the deposition pressure. The dielectricconstant of BFO films prepared at various conditions shows 127~187at 1kHz. The leakage current densityof BFO films annealed at 500oC was approximately two orders of magnitude lower than that of 550oC. Theleakage current density of the BFO films deposited at 10~30m Torr was about 5×10-6~3×10-2A/cm2 at 100kV/cm. Due to the high leakage current, saturated P-E curves were not obtained in BFO films. BFO film annealedat 500oC exhibited remnant polarization(2Pr) of 26.4µC/cm2 at 470kV/cm.

Ba(Ti,Sn)O3 thin films, for use as dielectrics for MLCCs, were grown from Sn doped BaTiO3 sourcesby e-beam evaporation. The crystalline phase, microstructure, dielectric and electrical properties of films wereinvestigated as a function of the (Ti＋Sn)/Ba ratio. When BaTiO3 sources doped with 20~50mol% of Sn wereevaporated, BaSnO3films were grown due to the higher vapor pressure of Ba and Sn than of Ti. However, itwas possible to grow the Ba(Ti,Sn)O3 thin films with ≤15mol% of Sn by co-evaporation of BTS and Ti metalsources. The (Ti＋Sn)/Ba and Sn/Ti ratio affected the microstructure and surface roughness of films and thedielectric constant increased with increasing Sn content. The dielectric constant and dissipation factor ofBa(Ti,Sn)O3 thin films with ≤15mol% of Sn showed the range of 120 to 160 and 2.5~5.5% at 1KHz,respectively. The leakage current density of films was order of the 10−9~10−8A/cm2 at 300KV/cm. The researchresults showed that it was feasible to grow the Ba(Ti,Sn)O3 thin films as dielectrics for MLCCs by an e-beamevaporation technique.

A nation's correction level develops in direct proportion to the nation's level. But the correctional principle does not suit our actuality. Since revival, our nation's correctional organization has been falling behind the other administrative organ's result of developmental reorganization. Nowadays, correction business is greatly increasing day by day and a second offense never decreased. Therefore correction administrative business' professional and effectual promotion needs increasingly. But now our nation's correction bureau is existing as a domestic shape of the ministry of justice which only is a assistance organ of the minister of justice. As a result, it is appeared that the difficulty of command and control in perfect order, the subordination of prosecutor, and correction civil servant's depressing the morale of the troops and so on. This study till now shows these theoretical problems at various literature but actually there was not smoothly allusion that how is the correction civil servant's thought who is charging with the correction business. Accordingly, I grasped the actual conditions for the development of correction administrative to correction civil servants who work at correction facility in the whole land's 46 sites and I understood what is necessary for this. As a result for the development of correction administrative, I knew that the modernization of correction facility, the independence of correction office, and the increment of correction facility are immediate. If the development of correction administrative is not, a criminal's social comeback is difficult. So the damage returns again a good general citizens. Consequently, now theoretically or actually the independence of correction service is not optional but indispensable. Any society, from the shady spot where has to advance for the first time we can say being advanced.

고밀도 DRAM에서 박막 커패시터로의 적용을 위해 Zr이 첨가된 (Ba(sub)1-x, Sr(sub)x)TiO3<원문차조> 박막이 r.f. magnetron sputter-ing 법에 의해 제조되었다. 증착된 박막들은 다결정질 구조를 보였으며 증착압력이 감소함에따라 Zr/Ti의 비가 현저히 증가하였으며 본 연구에서는 얻어진 박막들은 100kHz에서 380∼525의 유전상수값을 나타냈다. 전압에 따른 커패시턴스와 분극량의 변화는 이력특성을 크게 보이지 않아 상유전상으로 형성되었음을 보였다. 누설전류밀도는 증착압력이 감소함에 따라 작아지는 경향을 보였고 10mTorr이상에서 증착된 박막의 경우 200kV/cm의 전계에서 10(sup)-7∼10(sup)-8A/cm2의 차수를 갖는 누설전류밀도를 보여 본 연구에서 제조된 (Ba(sub)1-x, Sr(sub)x)(Ti(sub)1-x, Zr(sub)x)O3<원문참조>박막은 고밀도 DRAm을 위한 커패시터에의 적용가능성을 보였다.

비휘발성 메모리 소자에의 적용을 위한 SrBi2Ta2O9(SBT)박막이 고순도의 Sr, Bi, Ti 금속타겟을 사용하여 Pt/Ti/SiO2/Si 기판 위에 reactive sputtering 법에 의해 증착되었다. 조성의 영향을 평가하기 위하여 Bi 타겟에 인가되는 전원의 변화와 열처리에 따른 C-F(capacitance-frequency), P-E(polarization-electric field), I-V(current-voltage)등의 전기적 특성이 조사되었다. Bi의 양이 증가함에 따라 Bi layer 구조를 나타내는 (105)회절 피크가 증가하였고 700˚C, 산소분위기에서 1시간 동안 열처리후 Sr과 Bi가 심하게 휘발되었으며 박막의 미세구조는 다공질이 되었다. 이러한 이유로 열처리된 박막의 누설 전류 밀도는 증가하였다. 열처리된 시편의 조성은 거의 화학양론비를 이루었으며 4.5μC/cm2의 Pr값을 갖는 강유전(ferroelectric)특성을 나타내었다.

256Mb DRAM에서 박막 커패시터로의 적용을 위해서(Ba0.5Sr0.5)/TiO3(BST)박막이 RF Magnetron Sprttering방법에 의해 제조되었다. BST박막의 결정화도는 기판온도가 높아짐에 따라 증가하였고 증착된 박막의 조성은 (Ba0.48Sr0.48)/TiO2.93이었다. 이때 Pt/Ti장벽층은 Si의 BST계면으로의 확산을 억제하였다. 100kHz에서의 유전상수 및 유전손실은 각각 320 및 0.022이었다. 인가전계도 (Charge Storage Density)는 40fC/μ m2, 누설전류밀도(Leakage Current Density)는 0.8μ A/cm2 로서 RF Matnetron sputtering방법에 의해 제조된 BST 박막이 256Mb DRAM 적용 가능함을 보였다.

2014년 8월 태풍 “나크리”가 북상하여 제주도의 윗세오름에 146.5 mm/hr 강수가 발생하였으나, 별다른 큰 피해는 없었고, 이달 말 부산에서는 130 mm/hr 집중호우로 인해 사망자 5인 등, 피해액 1,200억원으로 특별재난지역으로 선포되는 등 많은 피해를 야기시켰다. 이는 해당지역의 방재취약성에 따라, 동일한 호우사상에 대한 피해정도가 매우 다를 수 있다는 것을 의미한다. 이와 같은 상황에서 기상청 호우특보 발표는 전국적으로 획일화된 기준으로 “호우주의보･경보”를 발표하나, 실제 전국적인 피해양상은 해당 지역별 지형특성, 인공적인 치수사업 개발정도 등의 사회·인문학적 재해발생요소에 따라 달라진다. 이에, 전국 46개 지자체의 지역별 방재역량을 산정하고 평가하기 위해, 자연재난 발생시 위험지표를 위험성 및 취약성 부문으로 구분하였다. 직접영향 요인, 자료의 공공신뢰성 등을 지표 선정 원칙으로 설정하여 과거 10년 동안 누적 재산피해액, 불투수면적비 등 세부지표 10개를 선정하였고, 이를 근거로 풍수해위험지수(H-index)를 개발하였다. 지표항목의 가중치는 설문조사 및 엔트로피 방법으로 비교·검토한 결과, 불확실성의 정량적 평가가 용이한 엔트로피 방법에 의해 가중치를 설정하여 대상지역의 지형특성과 위험등급의 적정성을 검토하였다. 전국 46개 지자체를 대상으로 기 발표된 과거 10년간의 호우특보 발표기간 및 강수량의 편차를 조사하여 평균오차에 의한 특보차등화계수를 도출하였다. 지역특성에 맞는 방재역량을 고려한 H-index와 토양의 함수조건을 알 수 있는 AMC를 활용하고, 기준강수량의 편차를 정량화한 특보차등화계수에 의해 침수피해 및 토사재해의 위험매트릭스를 사용하여 사전에 인지할 수 있는 지역별 방재기상특보 설정기법을 제시하였다.

Physically-based resampling scheme for roughness coefficient of surface runoff considering the spatial landuse distribution was suggested for the purpose of effective operational application of recent grid-based distributed rainfall runoff model. Generally grid scale(mother scale) of hydrologic modeling can be greater than the scale (child scale) of original GIS thematic digital map when the objective basin is wide or topographically simple, so the modeler uses large grid scale. The resampled roughness coefficient was estimated and compared using 3 different schemes of Predominant, Composite and Mosaic approaches and total runoff volume and peak streamflow were computed through distributed rainfall-runoff model. For quantitative assessment of biases between computational simulation and observation, runoff responses for the roughness estimated using the 3 different schemes were evaluated using MAPE(Mean Areal Percentage Error), RMSE(Root-Mean Squared Error), and COE(Coefficient of Efficiency). As a result, in the case of 500m scale Mosaic resampling for the natural and urban basin, the distribution of surface runoff roughness coefficient shows biggest difference from that of original scale but surface runoff simulation shows smallest, especially in peakflow rather than total runoff volume.

도시 배수구역의 유출특성을 해석하기 위하여서는 유역의 지형특성 및 유출경로를 고려하여 소유역을 분할하고 배수계통에 대한 유출량을 분석하게 되며, 이 과정에서 각 소유역의 도달시간과 시간-면적곡선은 유역형상에 따라 상이하게 구성되므로, 이로 인한 유출특성 또한 크게 변화하게 된다. SWMM 및 ILLUDAS 모형에서는 유역형상을 단순 직사각형으로 가정하여 해석함으로써 유역의 기하학적 형상이 지표면 유출에 미치는 영향을 충분히 반영하지 못하는 한계를 개선하