야생동물의 행동권과 서식지 이용 패턴을 이해하는 것은 동물의 보호를 위해 매우 중요하다. 그 중 특히 이동 철새의 경우에는 종에 따라 다양한 번식지, 월동지, 중간기착지 환경을 갖기 때문에 행동권과 서식지 이용 패턴을 파악하기 매우 어렵다. 천연기념물 제 205-1호로 지정된 저어새 (Platalea minor)는 세계자연보전연맹 적색목록(IUCN Red List)에 등재되어 있는 국제적인 보호종으로, 전 세계 개체군의 대부분이 우리나라 서해 무인도서에서 번식하고 홍콩이나 타이완 등지에서 월동하는 것으로 알려져 있다. 국내 번식지는 칠산도, 납대기섬, 석도, 비도, 남동유수지, 각시암, 수하암, 서만도, 구지도 등으로 알려져 있으며, 칠산도는 국내 최남단 저어새 번식지로 천연기념물 제 389호로 지정되어 있으며, 1991년 저어새 최초 번식이 확인된 이후 점차 번식 개체군이 증가하고 있다. 하지만 저어새 개체군에 관한 구체적인 행동권 및 이동 특성 연구는 미흡한 실정이다. 따라서 본 연구는 칠산도에서 이소한 저어새의 번식지 및 월동지 행동권 분석을 통해 이동 패턴과 서식지 정보를 파악하여 저어새의 보존 관리방안의 기초 자료로 확인하고자 한다. 칠산도에서 번식하는 저어새의 번식 현황 조사를 위해 2017년 3월부터 6월까지 매월 1회씩 총 4회 조사를 실시 하였으며, 이소한 저어새 4개체를 mist-net을 이용하여 포획 후 각각 개체에 고유번호(nhc1701, nhc1702, nhc1703, nhc1704)를 부여하고 야생동물위치추적장치(WT-300)를 부착하여 방사하였다. GPS 좌표는 4시간 간격으로 송신하도록 하였으며, 매일 2차례 좌표를 수신받았다. 수신된 좌표는 ArcGIS 10.3을 이용하여 분석하였으며, 최소볼록다각형법(Minimum Convex Polygon Method; MCP)과 커널밀도 측정법(Kernel Density Estimation; KDE)를 활용해 행동권을 파악하였다. 연구결과 저어새 4개체의 번식지인 칠산도와 백수 갯벌의 행동권은 평균 60.14 ± 24.91 km2 (MCP), KDE 90%는 28.01 ± 5.54 km2, 핵심서식지로 분류할 수 있는 KDE 50%는 6.18 ± 1.11 km2 으로 나타났다. 월동지 행동권의 경우 평균 39.98 ± 31.65 km2 (MCP), KDE 90%는 19.94 ± 12.36 km2, KDE 50%는 6.43 ± 4.95 km2 으로 나타났다. 번식지와 월동지의 저어새 행동권은 유의한 차이가 발견되지 않았다(MCP; t = -0.761, p = 0.50, KDE 90%; t = -1.138, p = 0.34, KDE 50%; t = 0.089, p = 0.93). 저어새의 행동권 분석 결과 번식지 및 월동지에서 수계 환경 의존도가 높은 경향을 보였으며, 이는 수계 환경변화 및 방해 요인이 저어새 서식 환경에 직･간접적 영향을 끼칠 수 있다. 따라서 향후 행동권 내 서식지의 특성, 환경요인 등을 분석하여 저어새의 번식지 및 월동지의 특성을 파악하고 보호 및 보전을 위한 기초 생태적인 연구가 필요하다.

호박꽃과실파리, Bactrocera scutellata (Hendel) (Diptera: Tephritidae),는 호박 등 박과식물의 해충으로 야외 트랩실험을 통해 호박꽃과실파리 수컷이 cue lure와 raspberry ketone에 유인되는 것이 확인되었으며, 전자현미경 관찰을 통해 호박꽃과실파리의 촉각(antennae)과 작은턱수염(maxillary palps)에 각각 다른 형태의 냄새감각기들이 존재한다는 것을 확인하였다. 이 결과를 바탕으로 Bactrocera 속 과실파리들의 parapheromone 성분들인 cue lure, raspberry ketone, methyl eugenol, 및 zingerone 등의 물질들이 촉각과 작은턱수염 중 어떤 감각기관에 의해 감지되는지 알아보기 위해 이 물질들과 식물 냄새성분인 3-octanone에 대한 호박꽃과실파리의 eleltroantennogram (EAG) 및 electropalpogram (EPG) 반응을 측정하였다. 그 결과 cue lure 및 raspberry ketone은 작은턱수염에서 큰 EPG 반응을 보였으나 촉각에서는 EAG 반응을 나타내지 않았다. 이와는 대조적으로 호박꽃과실파리의 기주식물인 호박에서 방출되는 냄새 성분 중 하나인 3-octanone은 촉각에서 큰 EAG 반응을 나타내었으나 작은턱수염에서는 아주 작은 EPG 반응만을 나타내었다. 이러한 결과는 호박꽃과 실파리 수컷에 강한 유인력을 나타내는 cue lure와 raspberry ketone이 촉각이 아니라 작은턱수염에 존재하는 냄새감각세포들에 의해 감지된다는 것을 의미하며 이것은 호박과실파리 등 아직 강력한 유인제가 알려져 있지 않은 다른 과실파리류의 유인제 개발에 유용한 정보가 될 것이다.

High power trends in the diesel engines due to engine downsizing do not provide noise attenuation that can be satisfied with the performance of the existing silencer on account of high frequency increases in the exhaust noise. This study improves the attenuation performance of the exhaust silencer of the diesel engine and suggests silencer structure that performs best attenuation performance, especially at the high frequency range in the exhaust noise. It proposes dual silencer structure with an average attenuation performance of 6.4 dB and a maximum of 10.7 dB in the high frequency range (over 500 Hz), and analyzes its characteristics compared with the existing silencer. The performance analysis is performed according to 'Measurements on silencers in situation–ISO 11820:1996 Acoustics' and describes the results of comparative analysis with the existing silencer.

In the 1930s, The Architectural Association of Joseon run the ‘Architectural Material Display’ on the 2nd floor of the Japan Life Insurance Building in Hwanggumjeong(currently Euljiro street). The purpose of this place was to introduce new architectural materials to builders. And they issued a 『建築資料型錄(Architectural Material Catalog)』and distributed it free of charge so that people in districts at long distances can make use of it. This catalog contains descriptions, photographs and drawings of various architectural materials that were common at the time, and the overseas branch address of the store is stated. The purpose of this research is to investigate the type and characteristics of architectural materials distributed in Northeast Asia around the 1930s, the region of sale, affiliated companies by closely analyzing the 『建築資料型錄』.

Background: Deficits of both ankle dorsiflexion range of motion (DFROM) and dynamic balance are shown in persons with chronic ankle instability and the elderly, with the risk of falls. Objects: This study aims to investigate the relationship between DFROM and dynamic balance in elderly subjects and young adults. Methods: Fifty-nine subjects were divided into three groups: ankle stability young group (SY), ankle instability young group (IY) and ankle stability older group (SO). We recruited three old subjects with ankle instability, but excluded them during a pilot testing due to the safety issue. DFROM was measured by weight bearing lunge test (WBLT) and dynamic balance was measured via star excursion balance test (SEBT) in anteromedial, medial, and posteromedial directions. The group differences in WBLT and SEBT and each group’s correlation between WBLT and SEBT were detected using the R statistical software package. Results: The dorsiflexion range of motion was significantly different between the SY, IY, and SO groups. The SO group showed the highest DFROM and IY group showed the lowest DFROM (SY: 45.88±.66˚, IY: 39.53±1.63˚, SO: 47.94±.50˚; p<.001). However, the SO group showed the lowest dynamic balance score for all SEBT directions (SY: 87.24±2.05 ㎝, IY: 83.20±1.30 ㎝, SO: 77.23±2.07 ㎝; p<.05) and there was no relationship between the dorsiflexion range of motion and dynamic balance in any group. Conclusion: Our findings suggest that ankle DFROM is not a crucial factor for dynamic stability regardless of aging and ankle instability. Other factors such as muscle strength or movement coordination should be considered for training dynamic balance. Therefore, we need to establish the rehabilitation process by measuring and treating ROM, balance, and muscle strength when treating young adults with and without ankle instability as well as elderly people.

The composition of the deicer sprayed on the highway is spreading over the highway by the scattering or snow removal activity, or car movement and consequently affecting the vegetation environment around the highway. These are the cause of the damage of fruit trees and crops, and also the cause of corrosion of highway structures. The goal of this study is to estimate the detected range of deicer components from a highway. The concentration of the deicer components in gauze and soil were investigated according to the crossing distance from the highway. The data collected were then used to estimate the concentration range of deicer components in a rage of distance up to 100 m from the highway where the deicer was spread. The sample time and weight of gauze were measured before and after installation, and the soil was collected at more than three points in parallel with the highway at the gauze installation point. The components in gauze and soil were investigated in addition to the deicer components (Ca2+, Na+, Cl-) as well as Mg2+ and K+. As Ca2+ and Cl- components of deicer were affected by agricultural use, Na+ component was selected as a tracer and further SAR (Sodium Adsorption Ratio) of soil was analyzed to examine the degree of influence on vegetation indirectly. The gauze concentration was evaluated by the concentration of the deicer ingredient at the background concentration of the blank gauze. The total amount of the deicer sprayed in the study road for 4 months (winter season) was about 93 ton/km. In the gauze test, the spread of the deicer was detected at a distance of 100 m in study area, but the concentration of the deicer in the gauze by distance decreased rapidly within 10 m from the highway. And concentration of the deicer components in gauze and soil came down after rainy season (August ~ Sep.). The results showed that the components of the deicer could be spread widely by the wind. The effective range of the deicer on vegetation based on SAR in soil was estimated to be less than 20 m from the highway. This study examines the concentration changes of the deicer components in gauze and soils and shows that deicer components sprayed on the highway are accumulated and moved over time by wind, snow removal, terrain, water system and land use around the highway.

Background: A limited hip rotational range of motion (ROM) has been considered to be one of characteristics of low back pain (LBP) in athletes. Although LBP frequently occurs in jiu-jitsu athletes, no previous has compared hip rotational ROM between jiu-jitsu athletes with and without LBP. Objects: The aim of the study was to compare ROM for hip internal rotation (IR) and external rotation (ER), and total hip rotation between jiu-jitsu athletes with and without LBP. Methods: Jiu-jitsu athletes were recruited for the LBP group (n1=15) and control group without LBP (n2=15). IR, ER, and total rotational range of hip joint were measured using a goniometer. Analysis of variance was used to compare the ROM between groups and sides. Results: The LBP group showed a significantly lower range of passive hip IR, passive total rotation, active IR, active ER, and active total rotation than the control group (p<.05). Dominant side of passive hip IR and active IR had a significantly lower ROM than non-dominant side (p<.05). In passive ER ROM, non-dominant side was significantly greater than dominant side (p<.05). Conclusion: Compared to jiu-jitsu athletes without LBP, athletes with LBP exhibit a loss of hip rotational ROM. Based on these results, clinicians and athletic trainers should measure hip rotational ROM when designing the management plan for jiu-jitsu athletes with LBP.

The purpose of this study was to examine the effects of the thoracic spine manipulation on spinal alignment (Cobb angle), pain, and trunk range of motion (ROM) in a patient with mild thoracic scoliosis. The Cobb angle was 11.0° and there was a right deviation of the thoracic spine. The subject had thoracic and lumbar pain, and had felt stiffness during turning of the trunk for about 3 years. Thoracic manipulation was applied at the upper thoracic spine as a therapeutic intervention three times per week for 5 weeks. After intervention, the Cobb angle decreased from 11.0° to 5.5° and the pain score decreased from 4.0 to 1.5, and the trunk left rotation ROM increased from 30.0° to 41.5°, and trunk right rotation ROM increased from 26.0° to 39.0°. These results suggest that the thrust thoracic manipulation technique had a positive effect on the spinal alignment, pain and trunk rotation ROM in patients with mild scoliosis.

디스플레이의 화질은 중요한 성능 지표이며, 균일도는 화질을 결정하는 주요 요소들 중의 하나이다. LED 매트릭 스 디스플레이 같이 화소마다 휘도 및 색역이 다른 경우, 디스플레이 휘도 및 컬러 균일도 개선을 위한 보정 작업이 수행되어야 한다. 적용의 편리성 때문에 대부분의 경우에 균일도 보정 방법은 모든 화소의 휘도 및 색역 중 가장 낮은 값 으로 보정을 수행하는 방식으로 진행되어왔다. 하지만, 이와 같은 방법은 균일도 보정 후 디스플레이의 휘도 및 색역이 너무 많이 감소하는 단점을 갖는다. 휘도 및 색역 감소량을 최소화하는 방법의 대안은 디스플레이가 균일하게 인지되는 범위를 도출한 후, 해당 범위 내에서 휘도 및 색역이 최대가 되는 값을 기준으로 디스플레이를 보정하는 것이다. 본 논 문에서는 이와 같은 디스플레이 균일도 보정 범위를 도출하는 방법을 제안한다. 제안하는 방법은 시각 실험을 통하여 화소간 휘도 및 색의 차이가 사람의 눈에 상이하게 인지되는 기준을 도출하고, 실험 결과를 사용하여 디스플레이 균일 도 보정 범위를 정량화 한다. 제안하는 방법의 성능은 시각 실험을 통하여 검증된다. 실험을 통해 제안하는 방법이 90% 이상의 높은 정확도로 균일도 보정 범위를 정확하게 도출하는 것을 확인할 수 있었다.

공정거래위원회는 2015년 기업메시징서비스 시장에서의 시장지배적 지위 남용에 관한 의결에서 관련 상품(서비스)시장의 범위를 ‘무선통신망을 통한 기업메시징서비스시장’으로 확정하였으나 이러한 판단은 더 이상 유효하지 않다. 스마트폰과 더불어 등장한, 한국 모바일메신저 앱 시장 의 94%를 점유하는 카카오톡이 기업메시징서비스 시장에서 변화를 일으키고 있기 때문이다. 카카오톡은 하이브리드 전송 서비스를 통해 무선통 신망을 보유하지 않고도 이를 보유한 이동통신사 업자들과 경쟁하고 있고 알림톡 서비스는 문자메 시지를 통한 기업메시징서비스보다 저렴하면서 정보 전달 기능 및 효용이 유사하여 이를 이용하는 업체의 수가 빠르게 증가하고 있다. 카카오톡은 이동통신사업자들의 무선통신망이라는 거대한 진입장벽을 이미 뛰어넘었으므로 당장 법원에 소송 계속 중인 사건에서 시정이 이루어지기는 어렵겠지만 향후 이러한 기술발전을 고려하여 기업메시징서비스 시장의 관련 상품시장 범위를 획정하는 법 집행 당국의 판단이 있어야 할 것이다. 기술의 발전이 법에 끼치는 영향에 적극적인 관심을 가짐으로써 새로운 법적 쟁점에 대응하는 자세가 중요한 이유이다.

From simple niche models to machine learning methods, there have been intensive efforts to understand the potentialdistribution of species in last two decades. Especially in the agricultural sector, recent SDM, Species Distribution Models,studies highly enthused to predict the potential distribution of invasive species under Climate Change. Beyond the distribution,efforts are needed to assess potential risk caused by the target pest. The Shared Socio-Economic Pathways (SSPs) are scenariosfor climate change impacts and adaptation measures. We used MaxEnt model to predict potential distribution of melonthrips with two RCPs (4.5, 8.5) and three SSPs (SSP1, SSP2, SSP3) scenarios. In agricultural land, the potential distributionof melon thrips increases under climate change, but the impact is reduced with the development-oriented scenario, SSP3.

황새목(Ciconiiformes) 저어새과(Threskiornithidae)에 속 하는 저어새(Platalea minor)는 국내에서 1968년 5월 31일 천연기념물 제 205-1호로 지정하여 보호하고 있고 세계자연 보전연맹 적색목록(IUCN Red List)에 멸종위기종(EN)으로 등재되어 있는 국제적인 보호종이다. 현재까지 국내에 알려 진 저어새 번식지는 칠산도, 납대기섬, 석도, 비도, 남동유수 지, 각시암, 수하암, 매도, 서만도, 구지도 등 총 22개이며 칠산도를 제외한 대부분의 번식지가 경기만 일대의 갯벌과 비무장지대에 위치하고 있다. 그 중 영광 칠산도는 천연기념 물 제389호로 지정하여 관리하고 있지만 서식지 축소 및 번 식지의 지속적인 자연훼손으로 번식개체수가 감소하고 있 다. 따라서 본 연구는 영광 칠산도를 대상으로 저어새의 번식 현황과 서식특성을 파악하여 보호관리방안 수립을 위한 기 초 데이터를 제공하는데 목적이 있다. 저어새 번식현황 파악을 위해 영광 칠산도를 대상으로 각 섬을 3월~6월까지 매월 1회씩 총 4회 조사를 실시하였으며, 번식 쌍은 관찰된 둥지의 최대개체수를 기록하였다. 그리고 무인센서카메라(Auto-7310) 총 10대를 육산도에 설치하여 첫 도래시기 및 행동특성을 확인하였다. 행동권 분석을 위해 이소한 저어새 유조 5개체를 대상으로 야생동물위치추적기 (WT-300)를 부착하여, 4시간 간격으로 GPS좌표를 송신하도 록 하였으며 매일 2차례 좌표를 수신 받았다. 본 연구에서는 체중의 2%이하의 야생동물위치추적기(30g 이내)를 부착하 여 저어새가 일상생활을 하는데 무리가 없도록 하였으며, 확 보한 자료는 야생동물위치추적기를 부착한 시점부터 하절기 (8월 31일)까지 한정하여 분석하였고 행동권 변화를 확인하 기 위해 2015년도에 부착한 3개체와 비교하였다. 연구결과, 2017년도 저어새 번식쌍은 총 85쌍으로 확인되 었으며 이는 2015년 93쌍으로 확인된 자료(국립문화재연구 소, 2015)에 비해 일부 감소한 수치이다. 특히 육산도의 개체 수 감소가 비교적 높게 확인되었는데 이는 약 3만마리 이상 의 괭이갈매기의 과도한 번식으로 인해 식생이 점차 사라지 고 토양이 유실되면서 암반이 노출된 상태로 서식지 환경이 열악해 지면서 나타난 현상으로 판단된다. 또한 섬의 면적에 비하여 저어새의 둥지재료로 이용될 만한 식생 및 둥지터가 부족하고, 2015년도에는 도란(盜卵) 및 빈번한 사람의 출입 에 따라 저어새 대부분이 사산도로 이동하여 번식하기 때문 일 것으로 사료된다. 무인센서카메라(Auto-7310)로 확인한 결과 3월 29일 새벽 1시 31분에 저어새 한 개체가 처음으로 포착되어 육산도의 저어새 첫 도래시기는 이 시점이거나 이 시점보다 빨랐을 것으로 예상할 수 있으며, 동일 개체로 추정되는 암·수 1쌍이 4월 2일 하루 총 6회(약 1시간 이하 간격으로 새벽 1시 42분 부터 새벽 5시 33분까지)의 구애활동을 하였고 구애활동의 1회 소요시간은 평균 약 4초였다. 저어새 유조의 번식지 내 행동권은 평균 0.22±0.09㎢(MCP), KDE 50%는 0.02±0.00㎢이었다. 2015년도에 부착한 개체 보다 행동권이 2배 이상 넓어진 것으로 확인되었으며, 번식 섬이 아닌 칠산도의 다른 섬으로 이동하는 빈도도 빈번한 것으로 파악되었다. 번식지를 벗어난 후 행동권은 평균 814.05±1482.89 ㎢(MCP), KDE 50%는 3.91±2.55㎢ 이었다. 2015년 자료에 비해 넓은 양상을 보였으나, 개체별로 차이가 크게 나타났다. MCP분 석의 경우 평균 800㎢이상의 넓은 행동권을 보였으나, 핵심서식 지라고 할 수 있는 KDE 50%에서는 5㎢내외의 행동권을 보였다. 이는 특정지역에 정착하기 전에는 취식지나 휴식지, 잠자리 등의 탐색을 위한 활동의 증가로 넓은 범위를 보이다가 정착한 후에는 일정한 행동범위에서 활동하기 때문에 나타난 결과라 판단된다.

Background:Rounded shoulder posture (RSP), a postural abnormality, might cause shoulder pain and pathologic conditions. Although most previous research has investigated RSP focusing on the proximal structures of the shoulder, such as the scapula and pectoralis muscles, the relationship between RSP and anterior distal structures of the upper extremity, such as the biceps brachii muscle and elbow joint, is not clearly understood.Objects:This study aimed to investigate the correlations between RSP and the biceps brachii length, elbow joint angle (EJA), pectoralis minor length, general pectoralis major length, humeral head anterior translation (HHAT), glenohumeral internal rotation (IR), external rotation (ER), and horizontal adduction (HAD).Methods:Twelve subjects with RSP (6 male, 6 female) were recruited. All subjects fulfilled the RSP criteria indicated by a distance ≥2.5 cm from the posterior aspect of the acromion to the table in the supine position. The examiner measured each of the following parameters twice: RSP, biceps brachii length, EJA, pectoralis minor length, pectoralis major length, HHAT, glenohumeral IR, ER, and HAD. Pearson’s correlation coefficient(r) was used to assess the correlation between RSP and all the variables.Results:There was a significant moderate positive correlation between RSP and biceps brachii length (r=.55, p=.032), moderate negative correlation between RSP and pectoralis minor length (r=-.62, p=.015), and moderate positive correlation between RSP and HHAT (r=.53, p=.038).Conclusion:The biceps brachii length, pectoralis minor length, and HHAT could be used to evaluate patients with RSP. Better understanding of the correlation between these factors and RSP could help in the development of effective methods to treat patients with this condition in clinical management.

With emphasis on native genetic resource, Korean native chicken is one of the major native breeds in poultry in Korea. The weight-age data from 216 pullets of Korean native chicken were used to fit the growth curve using Gompertz model. Live weights have been recorded every three weeks for 36 weeks for 5 strains. All available weight data from birth to the 6 specific ages of week were used for the estimation of parameters. The variation in estimates of mature weight (A) decreased with the increase of age 21 through 36 weeks for all 5 strains studied. However, the variation of rate of maturing (k) showed a tendancy increase with the increase of age. These results indicate that the fitting of growth curve is getting more stable for asymptotic value (A) and more flexible for curve shape (k) with the increase of weight-age data range. Correlations among estimates of A and among estimates of k at various ages showed the highest range of 0.93 ~ 0.99 between 30 and 36 weeks except for the maturing rate (k) of red brown strains. The correlations between A and k tended to fluctuate and were not significant statistically at various ages. Thus, the estimates of growth curve parameters, A and k suitable for genetic studies in Korean native chicken can be derived from accumulated weight-age data after 30 weeks of age.

The aim of this paper is to clarify the structural stability of Refracted Telescopic Boom in 30m Class with the Property of Working Range Insulation. The boom of insulation special vehicle consists of a 3-stage telescopic boom, 2-stage refracting boom, insulation boom and effector. The catia solid geometry of the boom was used to generate both a basic ADAMS model and the finite element meshes for the flexible components. The flexible bodies were generated by using the finite element program of ANSYS and then imported into the ADAMS model and their flexibility accounted to the dynamic analysis of boom. Embedding finite element representations within the ADAMS model, offers the advantage being able to perform the durability analysis and the resulting damage. Through this approach, the crack locations(hot spots) in a prototype can be predicted successfully, thereby validating the analysis procedure.

Long-range visual marine aids to navigation are not required for current marine navigational practices. Therefore, the objective of this study was to develop a minimum luminous range for major lighthouses that are still in existence to sustain the operation of the lighthouses in the future. Two steps were involved in the determination of the minimum luminous range, namely the modification of the existing geographical range formula, and the finding of a strong linear correlation between the light intensity and the luminous range with the lowest gradient possible in a graph. The application of the minimum luminous range would eliminate the loom of light beyond the geographical range of the lighthouse. This approach was applied to seven major lighthouses in Peninsular Malaysia, which resulted in a minimum luminous range of between 12 nm to 14 nm, which was a reduction from the existing range of 18 nm to 25 nm. The validation of the minimum luminous range was performed in two ways; using a Full Mission Ship Simulator (FMSS), and matching the proposed minimum luminous range with the lighting system available. The results of the validation by using the FMSS between the luminous range of 25 nm and 14 nm showed that the light could be sighted and identified at 58.7 nm and 58.6 nm, respectively, which was, therefore, not significant. The validation by matching with the lighting equipment available in the market showed that the eight-tier VLB-44, which has replaced the rotating lighting system in the US since 2008, was highly matched with the proposed minimum luminous range. This further validated the minimum luminous range. The minimum luminous range is sufficient for current navigational uses and may reduce the costs for procuring and maintaining lighting systems, and will be able to sustain the operations of lighthouses in this GNSS age.

This study concerned the analysis on the efficiency of the conversion of water tank type supply system to direct water supply system to examine the feasibility of the conversion, as well as the calculation of optimal conversion range that enables the supply of safe, high-quality water at stable pressure in accordance with the standards of water supply facility. The results of this research showed that when converting water supply system from water tank type supply system to direct water supply system, more nodal points could be properly converted and more reduction of electricity usage was expected in case water pressure rather than residence time was fixed. This means that higher efficacy can be obtained by fixing water pressure when converting water supply system. However, since the number of the locations that received on-spot inspection was small and the electricity usage measured was not exclusively by water supply facility, it is difficult to judge that such reduction of electricity usage accurately represents reduced electricity usage by water supply facility alone. therefore, after having secured on-spot information about a larger number of locations in apartment complexes that have converted water supply system, and utilizing information about electricity usage exclusively by water supply facility, the proposed method of this research could be applied to accurately deducing expected reduction of electricity usage by water supply facilities of various other apartment complexes. It is also considered possible to deduce an effective operation method of water supply system by finding out an area that shows low pressure or low residual chlorine concentration in the optimal conversion range of water supply, followed by estimating the proper location of pumping station or the proper chlorine dosage at the power purification plant that supply water to the target area.