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A Multicenter Pilot Study of Biliary Atresia Screening Using Digital Stool Color Imaging

  • Kannamon Waitayagitgumjon;Wannisa Poocharoen;Suchin Trirongjitmoah;Kriengsak Treeprapin;Arada Suttiwongsing;Thetiya Wirifai;Chira Trirongchitmoh;Pitiporn Tangkabuanbutr
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.27 no.3
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    • pp.168-175
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    • 2024
  • Purpose: The presence of alcoholic stool in biliary atresia (BA) patients is the basis of a stool color card (SCC), a screening tool that has led to more patients receiving Kasai portoenterostomy earlier. This study aimed to evaluate the color image processing of stool images captured using smartphones. We propose that measuring digital color parameters is a more objective method for identifying BA stools and may improve the sensitivity of BA screening. Methods: A prospective study was conducted in five hospitals in Thailand between October 1, 2020, and December 31, 2021. Stools from infants presenting with jaundice, acholic stool, or dark-colored urine were photographed. Digital image color analysis was performed, and software was developed based on the color on the original SCC. Sensitivity and specificity for predicting BA stools were compared between the SCC and the software. Results: Of 33 infants eligible for data collection, 19 were diagnosed with BA. Saturation and blue were two potential digital color parameters used to differentiate BA stools. The receiver operating characteristic curve was used to determine the optimum cutoff point of both values, and when saturation ≤56 or blue ≥61 was set as a threshold for detecting BA stool, high accuracy was achieved at 81.8% and 78.8%, respectively. Conclusion: Digital image processing is a promising technology. With appropriate cutoff values of saturation in hue, saturation, value and blue in red, green, blue color models, BA stools can be identified, and equivocal-colored stools of non-BA patients can be differentiated with acceptable accuracy in infants presenting with jaundice.

Assessment of Occupational Health Risks for Maintenance Work in Fabrication Facilities: Brief Review and Recommendations

  • Dong-Uk Park;Kyung Ehi Zoh;Eun Kyo Jeong;Dong-Hee Koh;Kyong-Hui Lee;Naroo Lee;Kwonchul Ha
    • Safety and Health at Work
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    • v.15 no.1
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    • pp.87-95
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    • 2024
  • Background: This study focuses on assessing occupational risk for the health hazards encountered during maintenance works (MW) in semiconductor fabrication (FAB) facilities. Objectives: The objectives of this study include: 1) identifying the primary health hazards during MW in semiconductor FAB facilities; 2) reviewing the methods used in evaluating the likelihood and severity of health hazards through occupational health risk assessment (OHRA); and 3) suggesting variables for the categorization of likelihood of exposures to health hazards and the severity of health effects associated with MW in FAB facilities. Methods: A literature review was undertaken on OHRA methodology and health hazards resulting from MW in FAB facilities. Based on this review, approaches for categorizing the exposure to health hazards and the severity of health effects related to MW were recommended. Results: Maintenance workers in FAB facilities face exposure to hazards such as debris, machinery entanglement, and airborne particles laden with various chemical components. The level of engineering and administrative control measures is suggested to assess the likelihood of simultaneous chemical and dust exposure. Qualitative key factors for mixed exposure estimation during MW include the presence of safe operational protocols, the use of air-jet machines, the presence and effectiveness of local exhaust ventilation system, chamber post-purge and cooling, and proper respirator use. Using the risk (R) and hazard (H) codes of the Globally Harmonized System alongside carcinogenic, mutagenic, or reprotoxic classifications aid in categorizing health effect severity for OHRA. Conclusion: Further research is needed to apply our proposed variables in OHRA for MW in FAB facilities and subsequently validate the findings.

Numerical Analysis Study on Micro-plastic Particle behavior According to the Shape of Cyclone Separator (Cyclone separator의 형상에 따른 미세플라스틱 입자 거동 수치해석 연구)

  • Insun Kang;Wonjun Seo;Dongho Yu;Yeongshik Kim;Hyeungchul Kim;Seokyeon Im
    • Tribology and Lubricants
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    • v.40 no.2
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    • pp.61-66
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    • 2024
  • Micro-plastics are synthetic high-differentiation chemicals of less than 5mm in size, and are deposited not only on the sea surface but also on the coast. If these micro-plastics are not properly separated from the sand, they can threaten marine ecosystems. Thus, in the present study, we aimed to apply cyclone separator to the micro-plastic retrieval in order to predict the movement of particles according to the formation of the cyclone separator by applying the centrifugal force of the particle in accordance with the rotational movement of the air. The cyclone separator has three shapes, the first one is a typical interconnected cyclone separator. The second is the horn form, except for the cylinder in a regular cyclone separator, and the third is a form that increases the horn's height twice in the second. The numerical analysis simulation of the Cyclone separator used the Fluent software package. The output speed of the Cyclone separator was 5 to 13m/s at 1m/s intervals. The simulated particles include sand, Styrofoam, PET, PP, and PU. Sand particles are assigned a fixed diameter of 2mm, while other particles have a diameter of 3mm. As a result of the analysis, the first form was not separated from plastic. The Styrofoam separation efficiency in the second showed its highest efficiency at 72.7% at 7m/s, and the efficiency decreased after 12m/s as the sand particles were mixed into the plastic attachment location. In the third form, the separation efficiency of Styrofoam at 12m/s was highest at 67.9%.

Experimental research on flow regime and transitional criterion of slug to churn-turbulent and churn-turbulent to annular flow in rectangular channels

  • Qingche He;Liang-ming Pan;Luteng Zhang;Wangtao Xu;Meiyue Yan
    • Nuclear Engineering and Technology
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    • v.55 no.11
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    • pp.3973-3982
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    • 2023
  • As for two-phase flow in rectangular channels, the flow regimes especially like churn-turbulent and annular flow are significant for the physical problem like Countercurrent Flow Limitation (CCFL). In this study, the rectangular channels with cross-sections of 4 × 66 mm, 6 × 66 mm, 8 × 66 mm are adopted to investigate the flow regimes of air-water vertical upward two phase flow under adiabatic condition. The gas and liquid superficial velocities are 0 ≤ jg ≤ 20m/s and 0.25 ≤ jf ≤ 3m/s respectively which covering bubbly to annular flow. The flow regimes are identified by random forest algorithm and the flow regime maps are obtained. As the results, the transitional void fraction from slug to churn turbulent flow fluctuate from 0.47 to 0.58 which is significantly affected by the dimensional size of channel and flow rate. Besides, the void fraction at transitional points from churn-turbulent (slug) to annular flow are 0.66-0.67, which are independent with the gap size. Furthermore, a new criteria of slug to churn-turbulent flow is established in this study. In addition, by introducing the interfacial force model, the criteria of churn-turbulent (slug) flow to annular flow is verified.

Towards Statistical Judgements of Occupational Stressor versus Performance Indication with Impact on Mental and Physical Health of Female College Teachers

  • Anjum Shaheen;Hussain Saleem;Abida Siddiqui;Samina Saleem;Uzma M. Panhwar;Jamshed Butt
    • International Journal of Computer Science & Network Security
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    • v.24 no.7
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    • pp.73-78
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    • 2024
  • The present world is full of challenges and opportunities for the women at work. Every woman works hard for academic growth and professional development. For the same reason they also face challenges every day such as stresses, tensions, problems and competitions. When these factors exceed above the strengths, the capabilities of a woman start drowning under stress. Stress is generally thought negative characteristic, but stress or tension maintained up to some level is necessary and effective towards work done at job. This paper covers the study relationship between job stressor and female teacher's performance. The study was carried out in Government Colleges of District Hyderabad, Pakistan. The teacher student relationship was selected as a stressor for female teachers. The study is descriptive in nature followed by method of correlation. A five point "Likert Scale" was developed to collect the data from the sample size of 158 college teachers drawn randomly and the collected data was assessed quantitatively. The relationship between the "teacher student" (as an indicator of job stress) and "female teachers' performance" was calculated by Pearson Correlation formula. The findings of the study show the significant correlations between the teacher student relationship and job stress in female teachers' performance where it is found that the stressor caused the poor Physical and Mental health of female teachers working in colleges.

Military Competition and Arms Control in Space (우주상 군비경쟁과 군비통제)

  • Shin, Dong-Chun;Cho, Hong-Je
    • The Korean Journal of Air & Space Law and Policy
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    • v.26 no.2
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    • pp.203-237
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    • 2011
  • Since USSR successfully launched its satellite "Sputnik"in 1957, many countries including US and USSR began military use of space, and engaged in arms race in space, which is against spirit and ideals of peaceful use of space as common heritage of mankind stipulated in many treaties such as Outer Space Treaty. With worsening Cold War between East and Western Bloc, this military use of space and arms race in space has been intensifying. Regarding the ideals of peaceful use of space, it is interpreted that military use of space is possible unless it does not have the purpose of aggression. The military use of space may have diverse forms such as attacking satellites in space, or attacking from satellites, making use of present and future technologies available which should include the use of nuclear and kinetic/hyper-speed weapons, laser, particle beams, near explosion, disturbance weapons in different directions (i.e., surface to space, space to space, and space to surface). Arms control is being implemented by the efforts of many countries in different formalities including legislature of international treaties under the auspices of UNCOPUOS and prohibition of weapons of mass destruction. Taking outstanding examples aiming at arms control by international community, there are confidence building measures (CBM), strengthening implementation of existing treaties, partial ban of nuclear tests, countryand regional approach, comprehensive approach and measures having legally binding force. While U.S. has surpassed other countries concerned in the area of military useof space, it withdrew from OST in early 2000s, thereby raising concern of international community. It requires concerted efforts of cooperationand implementation by international society to make sure peace of mankind and environmental conservation through arms control in space. Observing de facto possession of nuclear weapons by North Korea following series of nuclear tests and launching satellites, and efforts of launching rockets by South Korea, it is strongly needed for both countries to take part in arms control efforts by international community.

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A Study on the Improvement of Airspace Legislation in Korea (우리나라 공역 법제의 개선방안)

  • Kim, Jong-Dae
    • The Korean Journal of Air & Space Law and Policy
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    • v.33 no.2
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    • pp.61-114
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    • 2018
  • Recently airspace became a hot issue considering today's international relations. However, there was no data that could be fully explained about a legal system of korean airspace, so I looked at law and practice about korean airspace together. The nation's aviation law sector is comletely separate from those related to civil and military aircraft, at least in legal terms. The Minister of Land, Infrastructure and Transport shall carry out his/her duties with various authority granted by the "Aviation Safety Act". The nation's aviation-related content is being regulated too much by the Ministry of Land, Infrastructure and Transport's notice or regulation, and there are many things that are not well known about which clauses of the upper law are associated with. The notice should be clearly described only in detail on delegated matters. As for the airspace system, the airspace system is too complex for the public to understand, and there seems to be a gap between law and practice. Therefore, I think it would be good to reestablish a simple and practical airspace system. Airspace and aviation related tasks in the military need to be clearly understood by distinguishing between those entrusted by the Minister of Land, Infrastructure and Transport and those inherent in the military. Regarding matters entrusted by the Minister of Land, Infrastructure and Transpor, it is necessary to work closely with the Minister of Land, Infrastructure and Transport when preparing related work guidelines, and to clarify who should prepare the guidelines. Regarding airspace control as a military operation, policies or guidelines that are faithful to military doctrine on airspace control are needed.

The International Legality of the North Korean Missile Test (북한미사일 실험의 국제법상 위법성에 관한 연구)

  • Shin, Hong-Kyun
    • The Korean Journal of Air & Space Law and Policy
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    • v.24 no.2
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    • pp.211-234
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    • 2009
  • North Korea conducted the launcher test, which, as North Korea claimed, belonged to the sovereign rights for the purpose of peaceful utilization and exploration of the outer space. The launching was allegedly done for the sole purpose of putting the satellite into earth orbit, while international community stressed the fact that the orbiting of satellite was not confirmed and that the technology used was not distinct from the purpose of building intercontinental ballistic missile. UN Security Council adopted the resolutions which took the effect that the launching was deemed as the missile launching, not the mere launcher test. North Korea declared the moratorium of suspending its test activity. Controversial issues have been raised regarding whether the launcher itself has the legal status of enjoying the freedom of space flight based upon the 1967 Outer Space Treaty. The resolutions, however, has put forward a binding instrument forbidding the launching. UN Security Council resolutions, however, should be read not as defining the missile test illegal, in that the language of resolutions, such as 'demand', should be considered as not formulating a sort of obligatory act or inact. On the other hand, the resolutions should be read as having binding force with respect to any activity relating to the weapons of mass destruction. The resolution 1718 is written in more specific language such as 'decides that the DPRK shall suspend all activities related to its ballistic missile programme and in this context re-establish its pre-existing commitments to a moratorium on missile launching'. Therefore, the lauching activity of the North Korea is banned by the UN Security Council resolution. It should be noted that the resolution does not include any specific provisions defining the space of activity of the North Korea as illegal. But, the legal effect of the moratorium is not denied as to its launching itself, which is corresponding to the missile test clearisibanned in accordance with the resolutions.

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A Study on the Peaceful Uses of Outer Space and International Law (우주의 평화적 이용에 관한 국제법 연구)

  • Kim, Han Taek
    • The Korean Journal of Air & Space Law and Policy
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    • v.30 no.1
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    • pp.273-302
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    • 2015
  • The term "peaceful uses of outer space" in the 1967 Outer Space Treaty appears in official government statements and multilateral outer space related treaties. However, the examination of the state practice leads to the conclusion that this term is still without an authoritative definition. As far as the meaning of 'peaceful use' in international law is concerned the same phrases in the UN Charter, the 1963 Treaty of Banning Nuclear Weapons Tests in the Atmosphere in Outer Space and Under Water, the 1956 Statute of IAEA, the 1959 Antarctic Treaty, the 1982 UN Convention on the Law of the Sea, the 1968 Nuclear Non-Proliferation Treaty and the 1972 United Nations Conference of the Human Environment were analysed As far as the meaning of 'peaceful uses of outer space' is concerned the same phrases the 1967 Outer Space Treaty, the 1979 Moon Treaty and the 1977 Convention on the Prohibition of Military or Any Other Hostile Use of Environmental Modification Techniques(ENMOD) were studied. According to Article IV of the 1967 Outer Space treaty, states shall not place in orbit around the earth any objects carrying nuclear weapons or any other kind of weapons of mass destruction, install such weapons on celestial bodies, or station such weapons in outer space in any other manner. The 1979 Agreement Governing the Activities of States on the Moon and Other Celestial Bodies repeats in Article III much of the Outer Space Treaty. This article prohibits the threat or use of force or any other hostile act on the moon and the use of the moon to commit such an act in relation to the earth or to space objects. This adds IN principle nothing to the provisions of the Outer Space Treaty relating to military space activities. The 1977 ENMOD refers to peaceful purposes in the preamble and in Article III. As far as the UN Resolutions are concerned, the 1963 Declaration of Legal Principles Governing the Activities of States in the Exp1oration and Use of Outer Space, the 1992 Principles Relevant to the Use of Nuclear Power Sources in Outer Space(NPS) were studied. And as far the Soft Laws are concerned the 2008 Draft Treaty on the Prevention of the Placement of Weapon in Outer Space and of the Threat or Use of Force against Outer Space Objects(PPWT), the 2002 Hague Code of Conduct against Ballistic Missile Prolifiration(HCoC) and 2012 Draft International Code of Conduct for Outer Space Activities(ICoC) were studied.

A Study on the Moderating Effect of Perceived Voluntariness in the Organizational Information System Usage and Performance (정보시스템 사용과 성과에 있어서 자발성의 조절효과에 관한 연구)

  • Lee, Seung-Chang;Lee, Ho-Geun;Jung, Chang-Wook;Chung, Nam-Ho;Suh, Eung-Kyo
    • Asia pacific journal of information systems
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    • v.19 no.2
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    • pp.195-221
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    • 2009
  • According to an industry report, a large number of organizations have invested in Organizational Information System(OIS) in the past few years. Several research results indicate that successful investments in OIS lead to productivity enhancement, while failed ones result in undesirable consequences such as financial losses and dissatisfaction among employees. In spite of huge investments, however, many organizations have failed in achieving the hoped-for returns from OIS. Thus, understanding user acceptance, adoption, and usage of new IS(Information Systems) is an important issue for IS practitioners. Indeed, study of the user acceptance of new information system has been one of the most important research topics in the contemporary IS literature. Several theoretical models are tested to examine 'user acceptance' and 'usage behavior' in IS context. While many research models incorporate 'ease of use' or 'usefulness' as important factors in explaining user acceptance, Technology Acceptance Model(TAM) has been one of the most widely applied models in user acceptance and usage behavior. Even in recent IS studies that employ theories of innovation diffusion in the area of IS implementation, a major focus has been on the user's perception of information technologies. In this research, we study 'voluntariness' as an important factor in IS acceptance by users. Voluntariness is defined as "the degree to which the use of the innovation is perceived as being voluntary, or of free will" When examining the diffusion of accepting OIS, a thoughtful consideration should be given to 'perceived voluntariness.' Current article has following research questions: 1) What models are appropriate to explain the success of OIS? and 2) How does the 'voluntariness' affect the success of OIS? In order to answer these questions, a research model is proposed to describe the detailed nature of association among three independent variables (IT usage level, task interdependency, and organizational support), a mediating variable (IS usage), a dependent variable (perceived performance), and a moderating variable(perceived voluntariness). The central claim of this article is that organizations hardly realize expected returns from OIS investments unless perceived voluntariness is effectively managed after operating OIS. As an example of OIS in this study we have selected the Intranet of Republic of Korea Air Force (ROKAF). ROKAF has implemented the Intranet in an attempt to improve communication and coordination within the organization. To test our research model and hypotheses, survey questionnaires were first sent out to 400 Intranet users. With the assistance of ROKAF, Intranet users were initially identified among its members, and subjects were randomly drawn from the pool. 377 survey responses were finally returned. The unit of measurement and analysis in this research is a personal level. Path analysis based on structural equation modeling was used to test research hypotheses. Construct validity represents accordance between the theoretical base concept of constructs and its measurement items. Tests for the reliability and discriminant validity are accepted, thus verifying our survey instrument. In this research, we have proposed a conceptual framework to highlight the importance of perceived voluntariness after organization deploys OIS. The results of our analysis present several key finding. First, all three independent variables (IT usage level, task interdependency, and organizational support) have significant effects on IS usage, which will eventually improve performance. Thus, IS usage plays a mediating role between antecedent variables (IT usage level. task interdependency, and organizational support) and performance improvement. Second, the effect of the task dependency was the highest for IS usage among the three antecedent variables. This is highly plausible since one of the Intranet's major capabilities is to facilitate communication among members within an organization. Accordingly, we conclude that the higher the task dependency, the higher Intranet usage. The effect of user's IT usage level was the second, while the effect of the organizational support was the third. Finally, the perceived voluntariness plays a pivotal role in enhancing perceived performance in personal level after launching the Intranet. Relationships among investigated variables were significantly different between groups with a high level and a low level of voluntariness. The impact of the Intranet usage on the performance was greater in the higher level voluntariness group than in the lower one. For the lower level voluntariness group, the user's IT usage had the highest effect on the Intranet usage among the three antecedent variables. In short, our study suggests that the higher the perceived voluntariness is the more IS usage will be. Perceived voluntariness was found to have a moderating effect on the relationships among user IT usage level, task interdependency, IS usage, and perceived performance, supporting all the hypotheses on the moderating effect. Most of all, user IT usage level has the strongest influence on IS usage, indicating that users with superior IT usage are more likely to enjoy a high level of perceived performance.