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A Study on the Australian Law Regarding RPAS (Remotely Piloted Aircraft System): Need for an International Approach

  • Wheeler, Joseph;Lee, Jae-Woon
    • The Korean Journal of Air & Space Law and Policy
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    • v.30 no.2
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    • pp.311-336
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    • 2015
  • This article surveys the current international law with respect to RPAS from both the public air law and private air law perspectives. It then reviews current and proposed Australian domestic RPAS regulation while emphasizing the peculiar risks in operation of RPAS; and how they affect concepts of liability, safety and privacy. While RPAS operations still constitute only a small portion of total operations within commercial aviation, international pilotless flight for commercial air transport remains a future reality. As the industry is developing so quickly the earlier the pursuit of the right policy solutions begins, the better the law will be able to cope with the technological realities when the inevitable risks manifest in accidents. The paper acknowledges that a domestic or regional approach to RPAS, typified by the legislative success of the Australian experience, is and continues to be the principal measure to deal with RPAS issues globally. Furthermore, safety remains the foremost factor in present and revised Australian RPAS regulation. This has an analogue to the international situation. Creating safety-related rules is imperative and must precede the creation or adoption of liability rules because the former mitigates the risk of accidents which trigger the application of the latter. The flipside of a lack of binding airworthiness standards for RPAS operators is potentially a strong argument that the liability regime (and particularly strict liability of operators) is unfair and unsuited to pilotless flight. The potential solutions the authors raise include the need for revised ICAO guidance and, in particular, SARPs with respect to RPAS air safety, airworthiness, and potentially liability issues for participants/passengers, and those on the ground. Such guidance could then be adapted swiftly for appropriate incorporation into domestic laws bypassing the need for or administrative burden and time it would take to activate the treaty process to deal with an arm of aviation that states know all too well is in need of safety regulation and monitoring.

A Study on Development and Site selection of an AIRFIELD (경비행장 개발 및 입지선정에 관한 연구)

  • Park, Sang-Yong
    • The Korean Journal of Air & Space Law and Policy
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    • v.30 no.2
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    • pp.3-36
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    • 2015
  • As of end of 2014, the population engaging in aviation activities for leisure has reached approximately 13 million, where approximately 356 cases involve a general aircraft, 200 cases involve light aircraft, and 636 cases involve an ULM. The industry for leisure has become a very promising industry in line with rapidly rising living standards which are expected to further increase in the future. The demand for such services is expected to increase over time. The purpose of this paper is to review the development and site selection of airfields in anticipation of these developments in the industry. While the government also has experience in the review of airfield location and candidate sites, it is not the government that carries out the actual construction. As such, the feasibility of the site needs to be verified in terms of actual construction. This study identified factors for Site Selection of factors through a review of related documents and existing research reports. A questionnaire was also used to collect the views of experts in the field, which was then analyzed. The Research model was confirmed in the layered form for an AHP analysis. The factors for Site Selection were identified as the technical / operational factors and economic / political elements for a two-stage configuration. The third step consisted of technical and operational elements. The final step is was constructed a total of 11 elements (weather, surface conditions, obstacle limitation surface, airspace conditions, operating procedures, noise problems, environmental issues, availability of facilities, construction and investment costs, contribution to the local economy, accessibility, demand / the proximity of demand). The surveys are conducted for more than 10 General and light aircraft pilots, professionals, and instructor. The analysis results showed a higher level in the technical / operating elements (73.2%) in the first step, while the next step sawa higher level of the operational elements (30.9%) than the other. The factors for Site Selection were any particular elements did not appear high, the weather conditions (17.5%), noise problems (19.8%), the proximity of demand (6%), accessibility (5.7%), environmental issues (11.1%), availability of facilities (8%), airspace conditions (7.9%), obstacle limitation surface (12%), construction and investment costs (4.2%) and to operating procedures (4.9%), contribution to the local economy (3.8%).

Acute Appendicitis -A Survey by the Korean Association of Pediatric Surgeons in 2006- (급성 충수염 - 2006년 대한소아외과학회회원 대상 전국조사 -)

  • Lee, Suk-Koo;Kim, D.Y.;Kim, S.Y.;Kim, S.C.;Kim, S.G.;Kim, W.K.;Kim, I.K.;Kim, J.E.;Kim, J.C.;Park, K.W.;Park, W.H.;Seo, J.M.;Song, Y.T.;Oh, J.T.;Lee, N.H.;Lee, D.S.;Lee, M.D.;Lee, S.C.;Chang, S.I.;Jun, Y.S.;Chung, S.Y.;Chung, S.E.;Chung, U.S.;Jung, P.M.
    • Advances in pediatric surgery
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    • v.13 no.2
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    • pp.203-211
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    • 2007
  • A nationwide survey on acute appendicitis (AAP) was undertaken among members of the Korean Association of Pediatric Surgeons. The members were required to complete a questionnaire and the case registration form for each patient during the 6 months period from the $1^{st}$ October, 2005 to $31^{st}$ March, 2006. Questionnaires were collected from 23 members. Four hundred seventy six patients were registered from 21 hospitals where the members were working. The male to female ratio was 1.67:1. Average age was 9 years and 5 months (range 21 months-20 years). Operations were performed on average 10.4 hours (range 1-230 hours) from arrival at hospital. The average operation time was 59.1 minutes. The average admission days were 5.8 days (range 2-45 days). The most frequent symptoms were abdominal pain (95.1 %), vomiting (50.6 %) and fever (43.7%). The average duration of symptoms was 42.2 hours (range 1 hour-22 days). Leukocytosis (WBC count > 10,000) was found in 85.9%. The most popular diagnostic tools were ultrasonography and CT. Open surgery was performed in 72.1 % and laparoscopic surgery in 27.5 %. Two laparoscopic surgeries were converted to open surgery (0.4 %). Simple appendicitis was found in 54.5 % and complicated appendicitis such as abscess, gangrenous change and perforation in 45.5%. According to the questionnaires 12 hospitals were performing open surgery only in all patients. Four hospitals were performing laparoscopic surgery in all patients. Seven hospitals are performing both surgical methods according to surgeon or occasion. Regarding the use of antibiotics in acute appendicitis, three kinds of antibiotics were used in 40 % of total simple appendicitis patients. The results showed the trend of management in acute appendicitis in Korea. Especially it is necessary for the members to discuss the use of antibiotics for prophylaxis in the simple appendicitis.

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Analysis of Prognostic Factors in Esophageal Perforation. (식도 천공의 예후 인자 분석)

  • 정인석;송상윤;안병희;오봉석;김상형
    • Journal of Chest Surgery
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    • v.34 no.6
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    • pp.477-484
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    • 2001
  • Background: Initial symptoms for esophageal perforation have not been clarified, but when there is no early diagnosis and proper treatment to follow immediately after the diagnosis, it is fatal for the patients. Therefore, this study attempted to discover the factors that influence the prognosis of esophageal perforation to contribute to the improvement of the treatment result. Material and Method: The subjects of this study are 32 patients who came to the hospital with esophageal perforation from October, 1984 to June, 2000. This study examined the items for clinical observation such as patients' sex, age, cause of the perforation, perforation site, the time spent until the beginning of the treatment, symptoms caused by the perforation and its complication, and treatment methods. This study tried to find out the relationship between the survival of patients and each item. Result: There were 24 male and 8 female patients and their mean age was 49.7+16.4. For the causes of perforation, there were 14 cases(43%) of iatrogenic perforation, which ranked first, caused by the medical instrument operation and surgical damage. As for the perforation sites, thoracic esophagus was the most common site(26 cases of 81.2%) and chest pain was the most frequent symptom. The complication caused by esophageal perforation showed the highest cases in the order of mediastinitis, empyema, sepsis and peritonitis. After the treatment, there were 23 cases of survival and 9 cases of mortality. The total mortality rate was 28.1% and the main causes of mortality were sepsis and acute respiratory distress syndrome(ARDS). As for the treatment, 8 cases(25.0%) treated the perforation successfully using conservative treatment only. As for the surgical treatment, there were 5 cases(15.6%) of cervical drainage, 7 cases (21.8%) of primary repair and 12 cases(37.5%) of esophageal reconstruction after performing an exclusion-diversion. There were 18 cases(56.2%) of complete treatment of esophageal perforation at its initial treatment and in 14 cases(43.8%) of treatment failure at its initial treatment, patients were completely cured in the next treatment stage or died during the treatment. The cases of perforation in thoracic esophagus, complication into severe mediastinitis or sepsis and the cases of failure at initial treatment showed a statistically significant mortality rate (p<0.05).

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Effects of Fractionated Stereotactic Radiotherapy for Primary Hepatocellular Carcinoma (원발성 간암의 분할 정위방사선치료 효과)

  • Choi Byeong Ock;Kang Ki Mun;Jang Hong Seok;Lee Snag-wook;Kang Young Nam;Chai Gyu Young;Choi Ihl Bhong
    • Radiation Oncology Journal
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    • v.23 no.2
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    • pp.92-97
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    • 2005
  • Purpose : Reports on the outcome of curative radiotherapy for the primary hepatocellular carcinoma (HCC) are rarely encountered in the literature. in this study, we report our experience of a clinical trial where fractionated stereotactic radiotherapy (SRT) was used in treating a primary HCC. Materials and Methods : A retrospective analysis was peformed on 20 patients who had been histologically diagnosed as HCC and treated by fractionated SRT. The long diameter of tumor measured by CT was $2\~6.5$ cm (average: 3.8 cm). A single dose of radiation used in fractionated SRT was S or 10 Gy: each dose was prescribed based on the planning target volume and normalized to $85\~99\%$ isocenter dose. Patients were treated $3\~5$ times per week for 2 weeks, with each receiving a total dose of 50 Gy (the median dose: 50 Gy). The follow up period was $\~55$ months (the median follow up period: 23 months). Results : The response rate was $50\%$ (12 patients), with 4 patients showing complete response ($20%$), 8 patients showing partial response ($40\%$), and 8 patients showing stable disease ($40\%$). The 1-year and 2-year survival rates were $70.0\%$ and $43.1\%$, respectively, and the median survival time was 20 months. The 1-year and 2-year disease free survival rates were $65\%$ and $32.5\%$, respectively, and the median disease-free survival rate was 19 months. Some acute complications of the treatment were noted as follows: dyspepsia in 12 patients ($60\%$), nausea/emesis in 8 patients ($40\%$), and transient liver function impairment in 6 patients ($30\%$). However, there was no treatment related death. Conclusion : The study indicates that fractionated SRT is a relatively safe and effective method for treating primary HCC. Thus, fractionated SRT may be suggested as a local treatment for HCC of small lesion and containing a single lesion, when the patients are inoperable or operation is refused by the patients. We thought that fractionated SRT is a challenging treatment modality for the HCC.

Particulate Matter and CO2 Improvement Effects by Vegetation-based Bio-filters and the Indoor Comfort Index Analysis (식생기반 바이오필터의 미세먼지, 이산화탄소 개선효과와 실내쾌적지수 분석)

  • Kim, Tae-Han;Choi, Boo-Hun;Choi, Na-Hyun;Jang, Eun-Suk
    • Korean Journal of Environmental Agriculture
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    • v.37 no.4
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    • pp.268-276
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    • 2018
  • BACKGROUND: In the month of January 2018, fine dust alerts and warnings were issued 36 times for $PM_{10}$ and 81 times for PM2.5. Air quality is becoming a serious issue nation-wide. Although interest in air-purifying plants is growing due to the controversy over the risk of chemical substances of regular air-purifying solutions, industrial spread of the plants has been limited due to their efficiency in air-conditioning perspective. METHODS AND RESULTS: This study aims to propose a vegetation-based bio-filter system that can assure total indoor air volume for the efficient application of air-purifying plants. In order to evaluate the quantitative performance of the system, time-series analysis was conducted on air-conditioning performance, indoor air quality, and comfort index improvement effects in a lecture room-style laboratory with 16 persons present in the room. The system provided 4.24 ACH ventilation rate and reduced indoor temperature by $1.6^{\circ}C$ and black bulb temperature by $1.0^{\circ}C$. Relative humidity increased by 24.4% and deteriorated comfort index. However, this seemed to be offset by turbulent flow created from the operation of air blowers. While $PM_{10}$ was reduced by 39.5% to $22.11{\mu}g/m^3$, $CO_2$ increased up to 1,329ppm. It is interpreted that released $CO_2$ could not be processed because light compensation point was not reached. As for the indoor comfort index, PMV was reduced by 83.6 % and PPD was reduced by 47.0% on average, indicating that indoor space in a comfort range could be created by operating vegetation-based bio-filters. CONCLUSION: The study confirmed that the vegetation-based bio-filter system is effective in lowering indoor temperature and $PM_{10}$ and has positive effects on creating comfortable indoor space in terms of PMV and PPD.

Salvage with Reverse Total Shoulder Arthroplasty after the Failure of Proximal Humeral Tumor Treatment (근위 상완골 종양 치료 실패 후 역 견관절 전치환물을 이용한 구제술)

  • Jeon, Dae-Geun;Cho, Wan Hyeong;Kim, Bum Suk;Park, Hwanseong
    • Journal of the Korean Orthopaedic Association
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    • v.53 no.6
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    • pp.505-512
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    • 2018
  • Purpose: Many reconstruction methods have been attempted after an en-bloc resection of the proximal humerus. In particular, the introduction of reverse shoulder arthroplasty (RSA) has made a breakthrough in the functional recovery of the shoulder. Nevertheless, RSA has limitations when the humeral bone stock loss is significant. In addition, it is unclear if RSA is effective in patients showing failure with non-operative treatment of a proximal humeral tumor. Materials and Methods: A reconstruction was performed using an overlapping allograft-RSA composite for 11 patients with a failed proximal humeral construct. Delayed RSA was performed on 6 patients with failed non-operative treatment. The pre- and postoperative Musculoskeletal Tumor Society (MSTS) score and the complications were addressed. Results: Overlapping allograft-RSA composite afforded a stable construct in 11 failed proximal humeral reconstructions and the patient's chief complaints were resolved. The mean time to the union of overlapped allograft-host junction was 5.5 months. Average preoperative MSTS score of 20.3 point increased to 25.7 point, postoperatively. Four of the six patients who had RSA within 4 years from the index operation showed arm elevation of more than $90^{\circ}$ whereas the remaining 5 patients showed some disability. The complications include one case each of dislocation and aseptic infection, which were resolved by changing the polyethylene liner and scar revision, respectively. None of the 6 patients who underwent delayed RSA after the failure of non-operative treatment showed arm elevation more than $90^{\circ}$. Conclusion: An overlapping allograft-RSA composite is a simple and reliable reconstructive modality in patients with massive bone loss. In patients with metastatic cancer necessitating a surgical resection at presentation, early conversion to RSA is recommended to secure functional recovery.

Development of Continuous Culture Process for Economic Production of Hyaluronic Acid (HA) Biosynthesized by Streptococcus zooepidemicus (Streptococcus zooepidemicus 유래 히알루론산의 경제적 생산을 위한 연속배양 공정 개발)

  • Kim, Soo Yeon;Chun, Gie-Taek
    • Microbiology and Biotechnology Letters
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    • v.48 no.4
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    • pp.525-532
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    • 2020
  • A continuous fermentation process was carried out to enhance hyaluronic acid (HA) production using Streptococcus zooepidemicus cells. During the 1st stage continuous operation from 8 h with a dilution rate of 0.029/h (D1), HA was produced in the range of 7.5-10 g/l. During the 2nd stage from 44 h with a dilution rate of 0.036/h (D2), HA production (8.28 g/l) was initially reduced to a small extent due to increase of dilution rate from D1 to D2, and then a new pseudo-steady state was formed within a few hours with a concurrent small variations of HA production. The HA amount produced during the latter part of the 2nd stage was stably maintained in the range of 8.28-9.48 g/l, about 4.7% less amount compared to the 1st stage. Due to 24% increase of dilution rate from D1 to D2, however, maximum volumetric productivity (DP) amounting to 0.341 g/l/h was obtained at 96 h during the 2nd stage. This maximum productivity obtained from the continuous culture turned out only a small increase (3%) as compared to the corresponding batch fermentation. However, it should be noted that, in the case of batch process, one run typically consists of serial stages of growth culture plus one final production culture. This implies that, if the continuous fermentation that practically needs no dead time necessary for the multi-stage growth cultures is run for longer period, the total amount of the accumulated HA would be far greater than the amount obtained from the corresponding batch culture performed for the identical period.

A Study for operation results of the comprehensive examination on tendering system in the cultural heritage repair and restoration, focusing on the cause of the decline in the winning bid rate (문화재수리 종합심사낙찰제·종합평가낙찰제 운영결과 및 낙찰률하락 원인 분석)

  • JUNG, Younghun;YUN, Hyundo
    • Korean Journal of Heritage: History & Science
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    • v.55 no.1
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    • pp.111-132
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    • 2022
  • The comprehensive examination on tendering system has been introduced to the Cultural Heritage repair and restoration field since 2016 to remedy the repair issues of South Gate in 2014. The Cultural Heritage Administration tried to attain the high performance of the cultural heritage repair and restoration works securing the proper payment for the repair and restoration works. It is high time to review the operating performance of the comprehensive examination on tendering system (hereinafter referred to as the "CEOTS"), as the system has been run for over 5 years to correspond with its original goal, i.e., "The Proper Payment in return for the High Performance of Repair and Restoration works." This study intends to analyze 114 tenders of CEOTS from 2016 to 2020. As a result of the analysis of 114 tenders, firstly, more than half of bid winners were in the top 20% of repair & restoration capacity disclosure amount list, which mostly fulfilled the goal of 'attaining high performance.' Secondly, as the winning bid rate is decreasing from 86.847% in 2017 to 85.488% in 2020, the goal of 'guarantee of a proper payment' is not achieved yet. Thirdly, the influence of Economic Evaluation section in CEOTS has been grown since the change of scoring system in CEOTS in 2019. This study identifies two reasons why the winning bid rate of CEOTS has decreased. Firstly, it is caused by the fact that 'the group that got more than 1st place' and 'the first place group' that are more than half of the total bidders have the decreasing bidding rate trend as the years go by. Secondly, the exclusion rate of 'the group that got more than 1st place' is higher than the exclusion rate of 'the group that got less than 1st place', which means the expected winning rate would be lowered. It is proposed that the revision of CEOTS code is needed, i.e. easing the strict rule concerning the exclusion rate as well as setting up the lower bidding limit to prevent the excessive decreasing winning bid rate.

An Artificial Intelligence Approach to Waterbody Detection of the Agricultural Reservoirs in South Korea Using Sentinel-1 SAR Images (Sentinel-1 SAR 영상과 AI 기법을 이용한 국내 중소규모 농업저수지의 수표면적 산출)

  • Choi, Soyeon;Youn, Youjeong;Kang, Jonggu;Park, Ganghyun;Kim, Geunah;Lee, Seulchan;Choi, Minha;Jeong, Hagyu;Lee, Yangwon
    • Korean Journal of Remote Sensing
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    • v.38 no.5_3
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    • pp.925-938
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    • 2022
  • Agricultural reservoirs are an important water resource nationwide and vulnerable to abnormal climate effects such as drought caused by climate change. Therefore, it is required enhanced management for appropriate operation. Although water-level tracking is necessary through continuous monitoring, it is challenging to measure and observe on-site due to practical problems. This study presents an objective comparison between multiple AI models for water-body extraction using radar images that have the advantages of wide coverage, and frequent revisit time. The proposed methods in this study used Sentinel-1 Synthetic Aperture Radar (SAR) images, and unlike common methods of water extraction based on optical images, they are suitable for long-term monitoring because they are less affected by the weather conditions. We built four AI models such as Support Vector Machine (SVM), Random Forest (RF), Artificial Neural Network (ANN), and Automated Machine Learning (AutoML) using drone images, sentinel-1 SAR and DSM data. There are total of 22 reservoirs of less than 1 million tons for the study, including small and medium-sized reservoirs with an effective storage capacity of less than 300,000 tons. 45 images from 22 reservoirs were used for model training and verification, and the results show that the AutoML model was 0.01 to 0.03 better in the water Intersection over Union (IoU) than the other three models, with Accuracy=0.92 and mIoU=0.81 in a test. As the result, AutoML performed as well as the classical machine learning methods and it is expected that the applicability of the water-body extraction technique by AutoML to monitor reservoirs automatically.